apply.c

   1 /*
   2  * apply.c
   3  *
   4  * Copyright (C) Linus Torvalds, 2005
   5  *
   6  * This applies patches on top of some (arbitrary) version of the SCM.
   7  *
   8  */
   9
  10 #include "cache.h"
  11 #include "config.h"
  12 #include "blob.h"
  13 #include "delta.h"
  14 #include "diff.h"
  15 #include "dir.h"
  16 #include "xdiff-interface.h"
  17 #include "ll-merge.h"
  18 #include "lockfile.h"
  19 #include "parse-options.h"
  20 #include "quote.h"
  21 #include "rerere.h"
  22 #include "apply.h"
  23
  24 static void git_apply_config(void)
  25 {
  26         git_config_get_string_const("apply.whitespace", &apply_default_whitespace);
  27         git_config_get_string_const("apply.ignorewhitespace", &apply_default_ignorewhitespace);
  28         git_config(git_default_config, NULL);
  29 }
  30
  31 static int parse_whitespace_option(struct apply_state *state, const char *option)
  32 {
  33         if (!option) {
  34                 state->ws_error_action = warn_on_ws_error;
  35                 return 0;
  36         }
  37         if (!strcmp(option, "warn")) {
  38                 state->ws_error_action = warn_on_ws_error;
  39                 return 0;
  40         }
  41         if (!strcmp(option, "nowarn")) {
  42                 state->ws_error_action = nowarn_ws_error;
  43                 return 0;
  44         }
  45         if (!strcmp(option, "error")) {
  46                 state->ws_error_action = die_on_ws_error;
  47                 return 0;
  48         }
  49         if (!strcmp(option, "error-all")) {
  50                 state->ws_error_action = die_on_ws_error;
  51                 state->squelch_whitespace_errors = 0;
  52                 return 0;
  53         }
  54         if (!strcmp(option, "strip") || !strcmp(option, "fix")) {
  55                 state->ws_error_action = correct_ws_error;
  56                 return 0;
  57         }
  58         return error(_("unrecognized whitespace option '%s'"), option);
  59 }
  60
  61 static int parse_ignorewhitespace_option(struct apply_state *state,
  62                                                  const char *option)
  63 {
  64         if (!option || !strcmp(option, "no") ||
  65             !strcmp(option, "false") || !strcmp(option, "never") ||
  66             !strcmp(option, "none")) {
  67                 state->ws_ignore_action = ignore_ws_none;
  68                 return 0;
  69         }
  70         if (!strcmp(option, "change")) {
  71                 state->ws_ignore_action = ignore_ws_change;
  72                 return 0;
  73         }
  74         return error(_("unrecognized whitespace ignore option '%s'"), option);
  75 }
  76
  77 int init_apply_state(struct apply_state *state,
  78                      const char *prefix,
  79                      struct lock_file *lock_file)
  80 {
  81         memset(state, 0, sizeof(*state));
  82         state->prefix = prefix;
  83         state->prefix_length = state->prefix ? strlen(state->prefix) : 0;
  84         state->lock_file = lock_file;
  85         state->newfd = -1;
  86         state->apply = 1;
  87         state->line_termination = '\n';
  88         state->p_value = 1;
  89         state->p_context = UINT_MAX;
  90         state->squelch_whitespace_errors = 5;
  91         state->ws_error_action = warn_on_ws_error;
  92         state->ws_ignore_action = ignore_ws_none;
  93         state->linenr = 1;
  94         string_list_init(&state->fn_table, 0);
  95         string_list_init(&state->limit_by_name, 0);
  96         string_list_init(&state->symlink_changes, 0);
  97         strbuf_init(&state->root, 0);
  98
  99         git_apply_config();
 100         if (apply_default_whitespace && parse_whitespace_option(state, apply_default_whitespace))
 101                 return -1;
 102         if (apply_default_ignorewhitespace && parse_ignorewhitespace_option(state, apply_default_ignorewhitespace))
 103                 return -1;
 104         return 0;
 105 }
 106
 107 void clear_apply_state(struct apply_state *state)
 108 {
 109         string_list_clear(&state->limit_by_name, 0);
 110         string_list_clear(&state->symlink_changes, 0);
 111         strbuf_release(&state->root);
 112
 113         /* &state->fn_table is cleared at the end of apply_patch() */
 114 }
 115
 116 static void mute_routine(const char *msg, va_list params)
 117 {
 118         /* do nothing */
 119 }
 120
 121 int check_apply_state(struct apply_state *state, int force_apply)
 122 {
 123         int is_not_gitdir = !startup_info->have_repository;
 124
 125         if (state->apply_with_reject && state->threeway)
 126                 return error(_("--reject and --3way cannot be used together."));
 127         if (state->cached && state->threeway)
 128                 return error(_("--cached and --3way cannot be used together."));
 129         if (state->threeway) {
 130                 if (is_not_gitdir)
 131                         return error(_("--3way outside a repository"));
 132                 state->check_index = 1;
 133         }
 134         if (state->apply_with_reject) {
 135                 state->apply = 1;
 136                 if (state->apply_verbosity == verbosity_normal)
 137                         state->apply_verbosity = verbosity_verbose;
 138         }
 139         if (!force_apply && (state->diffstat || state->numstat || state->summary || state->check || state->fake_ancestor))
 140                 state->apply = 0;
 141         if (state->check_index && is_not_gitdir)
 142                 return error(_("--index outside a repository"));
 143         if (state->cached) {
 144                 if (is_not_gitdir)
 145                         return error(_("--cached outside a repository"));
 146                 state->check_index = 1;
 147         }
 148         if (state->check_index)
 149                 state->unsafe_paths = 0;
 150         if (!state->lock_file)
 151                 return error("BUG: state->lock_file should not be NULL");
 152
 153         if (state->apply_verbosity <= verbosity_silent) {
 154                 state->saved_error_routine = get_error_routine();
 155                 state->saved_warn_routine = get_warn_routine();
 156                 set_error_routine(mute_routine);
 157                 set_warn_routine(mute_routine);
 158         }
 159
 160         return 0;
 161 }
 162
 163 static void set_default_whitespace_mode(struct apply_state *state)
 164 {
 165         if (!state->whitespace_option && !apply_default_whitespace)
 166                 state->ws_error_action = (state->apply ? warn_on_ws_error : nowarn_ws_error);
 167 }
 168
 169 /*
 170  * This represents one "hunk" from a patch, starting with
 171  * "@@ -oldpos,oldlines +newpos,newlines @@" marker.  The
 172  * patch text is pointed at by patch, and its byte length
 173  * is stored in size.  leading and trailing are the number
 174  * of context lines.
 175  */
 176 struct fragment {
 177         unsigned long leading, trailing;
 178         unsigned long oldpos, oldlines;
 179         unsigned long newpos, newlines;
 180         /*
 181          * 'patch' is usually borrowed from buf in apply_patch(),
 182          * but some codepaths store an allocated buffer.
 183          */
 184         const char *patch;
 185         unsigned free_patch:1,
 186                 rejected:1;
 187         int size;
 188         int linenr;
 189         struct fragment *next;
 190 };
 191
 192 /*
 193  * When dealing with a binary patch, we reuse "leading" field
 194  * to store the type of the binary hunk, either deflated "delta"
 195  * or deflated "literal".
 196  */
 197 #define binary_patch_method leading
 198 #define BINARY_DELTA_DEFLATED   1
 199 #define BINARY_LITERAL_DEFLATED 2
 200
 201 /*
 202  * This represents a "patch" to a file, both metainfo changes
 203  * such as creation/deletion, filemode and content changes represented
 204  * as a series of fragments.
 205  */
 206 struct patch {
 207         char *new_name, *old_name, *def_name;
 208         unsigned int old_mode, new_mode;
 209         int is_new, is_delete;  /* -1 = unknown, 0 = false, 1 = true */
 210         int rejected;
 211         unsigned ws_rule;
 212         int lines_added, lines_deleted;
 213         int score;
 214         int extension_linenr; /* first line specifying delete/new/rename/copy */
 215         unsigned int is_toplevel_relative:1;
 216         unsigned int inaccurate_eof:1;
 217         unsigned int is_binary:1;
 218         unsigned int is_copy:1;
 219         unsigned int is_rename:1;
 220         unsigned int recount:1;
 221         unsigned int conflicted_threeway:1;
 222         unsigned int direct_to_threeway:1;
 223         unsigned int crlf_in_old:1;
 224         struct fragment *fragments;
 225         char *result;
 226         size_t resultsize;
 227         char old_sha1_prefix[41];
 228         char new_sha1_prefix[41];
 229         struct patch *next;
 230
 231         /* three-way fallback result */
 232         struct object_id threeway_stage[3];
 233 };
 234
 235 static void free_fragment_list(struct fragment *list)
 236 {
 237         while (list) {
 238                 struct fragment *next = list->next;
 239                 if (list->free_patch)
 240                         free((char *)list->patch);
 241                 free(list);
 242                 list = next;
 243         }
 244 }
 245
 246 static void free_patch(struct patch *patch)
 247 {
 248         free_fragment_list(patch->fragments);
 249         free(patch->def_name);
 250         free(patch->old_name);
 251         free(patch->new_name);
 252         free(patch->result);
 253         free(patch);
 254 }
 255
 256 static void free_patch_list(struct patch *list)
 257 {
 258         while (list) {
 259                 struct patch *next = list->next;
 260                 free_patch(list);
 261                 list = next;
 262         }
 263 }
 264
 265 /*
 266  * A line in a file, len-bytes long (includes the terminating LF,
 267  * except for an incomplete line at the end if the file ends with
 268  * one), and its contents hashes to 'hash'.
 269  */
 270 struct line {
 271         size_t len;
 272         unsigned hash : 24;
 273         unsigned flag : 8;
 274 #define LINE_COMMON     1
 275 #define LINE_PATCHED    2
 276 };
 277
 278 /*
 279  * This represents a "file", which is an array of "lines".
 280  */
 281 struct image {
 282         char *buf;
 283         size_t len;
 284         size_t nr;
 285         size_t alloc;
 286         struct line *line_allocated;
 287         struct line *line;
 288 };
 289
 290 static uint32_t hash_line(const char *cp, size_t len)
 291 {
 292         size_t i;
 293         uint32_t h;
 294         for (i = 0, h = 0; i < len; i++) {
 295                 if (!isspace(cp[i])) {
 296                         h = h * 3 + (cp[i] & 0xff);
 297                 }
 298         }
 299         return h;
 300 }
 301
 302 /*
 303  * Compare lines s1 of length n1 and s2 of length n2, ignoring
 304  * whitespace difference. Returns 1 if they match, 0 otherwise
 305  */
 306 static int fuzzy_matchlines(const char *s1, size_t n1,
 307                             const char *s2, size_t n2)
 308 {
 309         const char *last1 = s1 + n1 - 1;
 310         const char *last2 = s2 + n2 - 1;
 311         int result = 0;
 312
 313         /* ignore line endings */
 314         while ((*last1 == '\r') || (*last1 == '\n'))
 315                 last1--;
 316         while ((*last2 == '\r') || (*last2 == '\n'))
 317                 last2--;
 318
 319         /* skip leading whitespaces, if both begin with whitespace */
 320         if (s1 <= last1 && s2 <= last2 && isspace(*s1) && isspace(*s2)) {
 321                 while (isspace(*s1) && (s1 <= last1))
 322                         s1++;
 323                 while (isspace(*s2) && (s2 <= last2))
 324                         s2++;
 325         }
 326         /* early return if both lines are empty */
 327         if ((s1 > last1) && (s2 > last2))
 328                 return 1;
 329         while (!result) {
 330                 result = *s1++ - *s2++;
 331                 /*
 332                  * Skip whitespace inside. We check for whitespace on
 333                  * both buffers because we don't want "a b" to match
 334                  * "ab"
 335                  */
 336                 if (isspace(*s1) && isspace(*s2)) {
 337                         while (isspace(*s1) && s1 <= last1)
 338                                 s1++;
 339                         while (isspace(*s2) && s2 <= last2)
 340                                 s2++;
 341                 }
 342                 /*
 343                  * If we reached the end on one side only,
 344                  * lines don't match
 345                  */
 346                 if (
 347                     ((s2 > last2) && (s1 <= last1)) ||
 348                     ((s1 > last1) && (s2 <= last2)))
 349                         return 0;
 350                 if ((s1 > last1) && (s2 > last2))
 351                         break;
 352         }
 353
 354         return !result;
 355 }
 356
 357 static void add_line_info(struct image *img, const char *bol, size_t len, unsigned flag)
 358 {
 359         ALLOC_GROW(img->line_allocated, img->nr + 1, img->alloc);
 360         img->line_allocated[img->nr].len = len;
 361         img->line_allocated[img->nr].hash = hash_line(bol, len);
 362         img->line_allocated[img->nr].flag = flag;
 363         img->nr++;
 364 }
 365
 366 /*
 367  * "buf" has the file contents to be patched (read from various sources).
 368  * attach it to "image" and add line-based index to it.
 369  * "image" now owns the "buf".
 370  */
 371 static void prepare_image(struct image *image, char *buf, size_t len,
 372                           int prepare_linetable)
 373 {
 374         const char *cp, *ep;
 375
 376         memset(image, 0, sizeof(*image));
 377         image->buf = buf;
 378         image->len = len;
 379
 380         if (!prepare_linetable)
 381                 return;
 382
 383         ep = image->buf + image->len;
 384         cp = image->buf;
 385         while (cp < ep) {
 386                 const char *next;
 387                 for (next = cp; next < ep && *next != '\n'; next++)
 388                         ;
 389                 if (next < ep)
 390                         next++;
 391                 add_line_info(image, cp, next - cp, 0);
 392                 cp = next;
 393         }
 394         image->line = image->line_allocated;
 395 }
 396
 397 static void clear_image(struct image *image)
 398 {
 399         free(image->buf);
 400         free(image->line_allocated);
 401         memset(image, 0, sizeof(*image));
 402 }
 403
 404 /* fmt must contain _one_ %s and no other substitution */
 405 static void say_patch_name(FILE *output, const char *fmt, struct patch *patch)
 406 {
 407         struct strbuf sb = STRBUF_INIT;
 408
 409         if (patch->old_name && patch->new_name &&
 410             strcmp(patch->old_name, patch->new_name)) {
 411                 quote_c_style(patch->old_name, &sb, NULL, 0);
 412                 strbuf_addstr(&sb, " => ");
 413                 quote_c_style(patch->new_name, &sb, NULL, 0);
 414         } else {
 415                 const char *n = patch->new_name;
 416                 if (!n)
 417                         n = patch->old_name;
 418                 quote_c_style(n, &sb, NULL, 0);
 419         }
 420         fprintf(output, fmt, sb.buf);
 421         fputc('\n', output);
 422         strbuf_release(&sb);
 423 }
 424
 425 #define SLOP (16)
 426
 427 static int read_patch_file(struct strbuf *sb, int fd)
 428 {
 429         if (strbuf_read(sb, fd, 0) < 0)
 430                 return error_errno("git apply: failed to read");
 431
 432         /*
 433          * Make sure that we have some slop in the buffer
 434          * so that we can do speculative "memcmp" etc, and
 435          * see to it that it is NUL-filled.
 436          */
 437         strbuf_grow(sb, SLOP);
 438         memset(sb->buf + sb->len, 0, SLOP);
 439         return 0;
 440 }
 441
 442 static unsigned long linelen(const char *buffer, unsigned long size)
 443 {
 444         unsigned long len = 0;
 445         while (size--) {
 446                 len++;
 447                 if (*buffer++ == '\n')
 448                         break;
 449         }
 450         return len;
 451 }
 452
 453 static int is_dev_null(const char *str)
 454 {
 455         return skip_prefix(str, "/dev/null", &str) && isspace(*str);
 456 }
 457
 458 #define TERM_SPACE      1
 459 #define TERM_TAB        2
 460
 461 static int name_terminate(int c, int terminate)
 462 {
 463         if (c == ' ' && !(terminate & TERM_SPACE))
 464                 return 0;
 465         if (c == '\t' && !(terminate & TERM_TAB))
 466                 return 0;
 467
 468         return 1;
 469 }
 470
 471 /* remove double slashes to make --index work with such filenames */
 472 static char *squash_slash(char *name)
 473 {
 474         int i = 0, j = 0;
 475
 476         if (!name)
 477                 return NULL;
 478
 479         while (name[i]) {
 480                 if ((name[j++] = name[i++]) == '/')
 481                         while (name[i] == '/')
 482                                 i++;
 483         }
 484         name[j] = '\0';
 485         return name;
 486 }
 487
 488 static char *find_name_gnu(struct apply_state *state,
 489                            const char *line,
 490                            const char *def,
 491                            int p_value)
 492 {
 493         struct strbuf name = STRBUF_INIT;
 494         char *cp;
 495
 496         /*
 497          * Proposed "new-style" GNU patch/diff format; see
 498          * http://marc.info/?l=git&m=112927316408690&w=2
 499          */
 500         if (unquote_c_style(&name, line, NULL)) {
 501                 strbuf_release(&name);
 502                 return NULL;
 503         }
 504
 505         for (cp = name.buf; p_value; p_value--) {
 506                 cp = strchr(cp, '/');
 507                 if (!cp) {
 508                         strbuf_release(&name);
 509                         return NULL;
 510                 }
 511                 cp++;
 512         }
 513
 514         strbuf_remove(&name, 0, cp - name.buf);
 515         if (state->root.len)
 516                 strbuf_insert(&name, 0, state->root.buf, state->root.len);
 517         return squash_slash(strbuf_detach(&name, NULL));
 518 }
 519
 520 static size_t sane_tz_len(const char *line, size_t len)
 521 {
 522         const char *tz, *p;
 523
 524         if (len < strlen(" +0500") || line[len-strlen(" +0500")] != ' ')
 525                 return 0;
 526         tz = line + len - strlen(" +0500");
 527
 528         if (tz[1] != '+' && tz[1] != '-')
 529                 return 0;
 530
 531         for (p = tz + 2; p != line + len; p++)
 532                 if (!isdigit(*p))
 533                         return 0;
 534
 535         return line + len - tz;
 536 }
 537
 538 static size_t tz_with_colon_len(const char *line, size_t len)
 539 {
 540         const char *tz, *p;
 541
 542         if (len < strlen(" +08:00") || line[len - strlen(":00")] != ':')
 543                 return 0;
 544         tz = line + len - strlen(" +08:00");
 545
 546         if (tz[0] != ' ' || (tz[1] != '+' && tz[1] != '-'))
 547                 return 0;
 548         p = tz + 2;
 549         if (!isdigit(*p++) || !isdigit(*p++) || *p++ != ':' ||
 550             !isdigit(*p++) || !isdigit(*p++))
 551                 return 0;
 552
 553         return line + len - tz;
 554 }
 555
 556 static size_t date_len(const char *line, size_t len)
 557 {
 558         const char *date, *p;
 559
 560         if (len < strlen("72-02-05") || line[len-strlen("-05")] != '-')
 561                 return 0;
 562         p = date = line + len - strlen("72-02-05");
 563
 564         if (!isdigit(*p++) || !isdigit(*p++) || *p++ != '-' ||
 565             !isdigit(*p++) || !isdigit(*p++) || *p++ != '-' ||
 566             !isdigit(*p++) || !isdigit(*p++))   /* Not a date. */
 567                 return 0;
 568
 569         if (date - line >= strlen("19") &&
 570             isdigit(date[-1]) && isdigit(date[-2]))     /* 4-digit year */
 571                 date -= strlen("19");
 572
 573         return line + len - date;
 574 }
 575
 576 static size_t short_time_len(const char *line, size_t len)
 577 {
 578         const char *time, *p;
 579
 580         if (len < strlen(" 07:01:32") || line[len-strlen(":32")] != ':')
 581                 return 0;
 582         p = time = line + len - strlen(" 07:01:32");
 583
 584         /* Permit 1-digit hours? */
 585         if (*p++ != ' ' ||
 586             !isdigit(*p++) || !isdigit(*p++) || *p++ != ':' ||
 587             !isdigit(*p++) || !isdigit(*p++) || *p++ != ':' ||
 588             !isdigit(*p++) || !isdigit(*p++))   /* Not a time. */
 589                 return 0;
 590
 591         return line + len - time;
 592 }
 593
 594 static size_t fractional_time_len(const char *line, size_t len)
 595 {
 596         const char *p;
 597         size_t n;
 598
 599         /* Expected format: 19:41:17.620000023 */
 600         if (!len || !isdigit(line[len - 1]))
 601                 return 0;
 602         p = line + len - 1;
 603
 604         /* Fractional seconds. */
 605         while (p > line && isdigit(*p))
 606                 p--;
 607         if (*p != '.')
 608                 return 0;
 609
 610         /* Hours, minutes, and whole seconds. */
 611         n = short_time_len(line, p - line);
 612         if (!n)
 613                 return 0;
 614
 615         return line + len - p + n;
 616 }
 617
 618 static size_t trailing_spaces_len(const char *line, size_t len)
 619 {
 620         const char *p;
 621
 622         /* Expected format: ' ' x (1 or more)  */
 623         if (!len || line[len - 1] != ' ')
 624                 return 0;
 625
 626         p = line + len;
 627         while (p != line) {
 628                 p--;
 629                 if (*p != ' ')
 630                         return line + len - (p + 1);
 631         }
 632
 633         /* All spaces! */
 634         return len;
 635 }
 636
 637 static size_t diff_timestamp_len(const char *line, size_t len)
 638 {
 639         const char *end = line + len;
 640         size_t n;
 641
 642         /*
 643          * Posix: 2010-07-05 19:41:17
 644          * GNU: 2010-07-05 19:41:17.620000023 -0500
 645          */
 646
 647         if (!isdigit(end[-1]))
 648                 return 0;
 649
 650         n = sane_tz_len(line, end - line);
 651         if (!n)
 652                 n = tz_with_colon_len(line, end - line);
 653         end -= n;
 654
 655         n = short_time_len(line, end - line);
 656         if (!n)
 657                 n = fractional_time_len(line, end - line);
 658         end -= n;
 659
 660         n = date_len(line, end - line);
 661         if (!n) /* No date.  Too bad. */
 662                 return 0;
 663         end -= n;
 664
 665         if (end == line)        /* No space before date. */
 666                 return 0;
 667         if (end[-1] == '\t') {  /* Success! */
 668                 end--;
 669                 return line + len - end;
 670         }
 671         if (end[-1] != ' ')     /* No space before date. */
 672                 return 0;
 673
 674         /* Whitespace damage. */
 675         end -= trailing_spaces_len(line, end - line);
 676         return line + len - end;
 677 }
 678
 679 static char *find_name_common(struct apply_state *state,
 680                               const char *line,
 681                               const char *def,
 682                               int p_value,
 683                               const char *end,
 684                               int terminate)
 685 {
 686         int len;
 687         const char *start = NULL;
 688
 689         if (p_value == 0)
 690                 start = line;
 691         while (line != end) {
 692                 char c = *line;
 693
 694                 if (!end && isspace(c)) {
 695                         if (c == '\n')
 696                                 break;
 697                         if (name_terminate(c, terminate))
 698                                 break;
 699                 }
 700                 line++;
 701                 if (c == '/' && !--p_value)
 702                         start = line;
 703         }
 704         if (!start)
 705                 return squash_slash(xstrdup_or_null(def));
 706         len = line - start;
 707         if (!len)
 708                 return squash_slash(xstrdup_or_null(def));
 709
 710         /*
 711          * Generally we prefer the shorter name, especially
 712          * if the other one is just a variation of that with
 713          * something else tacked on to the end (ie "file.orig"
 714          * or "file~").
 715          */
 716         if (def) {
 717                 int deflen = strlen(def);
 718                 if (deflen < len && !strncmp(start, def, deflen))
 719                         return squash_slash(xstrdup(def));
 720         }
 721
 722         if (state->root.len) {
 723                 char *ret = xstrfmt("%s%.*s", state->root.buf, len, start);
 724                 return squash_slash(ret);
 725         }
 726
 727         return squash_slash(xmemdupz(start, len));
 728 }
 729
 730 static char *find_name(struct apply_state *state,
 731                        const char *line,
 732                        char *def,
 733                        int p_value,
 734                        int terminate)
 735 {
 736         if (*line == '"') {
 737                 char *name = find_name_gnu(state, line, def, p_value);
 738                 if (name)
 739                         return name;
 740         }
 741
 742         return find_name_common(state, line, def, p_value, NULL, terminate);
 743 }
 744
 745 static char *find_name_traditional(struct apply_state *state,
 746                                    const char *line,
 747                                    char *def,
 748                                    int p_value)
 749 {
 750         size_t len;
 751         size_t date_len;
 752
 753         if (*line == '"') {
 754                 char *name = find_name_gnu(state, line, def, p_value);
 755                 if (name)
 756                         return name;
 757         }
 758
 759         len = strchrnul(line, '\n') - line;
 760         date_len = diff_timestamp_len(line, len);
 761         if (!date_len)
 762                 return find_name_common(state, line, def, p_value, NULL, TERM_TAB);
 763         len -= date_len;
 764
 765         return find_name_common(state, line, def, p_value, line + len, 0);
 766 }
 767
 768 /*
 769  * Given the string after "--- " or "+++ ", guess the appropriate
 770  * p_value for the given patch.
 771  */
 772 static int guess_p_value(struct apply_state *state, const char *nameline)
 773 {
 774         char *name, *cp;
 775         int val = -1;
 776
 777         if (is_dev_null(nameline))
 778                 return -1;
 779         name = find_name_traditional(state, nameline, NULL, 0);
 780         if (!name)
 781                 return -1;
 782         cp = strchr(name, '/');
 783         if (!cp)
 784                 val = 0;
 785         else if (state->prefix) {
 786                 /*
 787                  * Does it begin with "a/$our-prefix" and such?  Then this is
 788                  * very likely to apply to our directory.
 789                  */
 790                 if (!strncmp(name, state->prefix, state->prefix_length))
 791                         val = count_slashes(state->prefix);
 792                 else {
 793                         cp++;
 794                         if (!strncmp(cp, state->prefix, state->prefix_length))
 795                                 val = count_slashes(state->prefix) + 1;
 796                 }
 797         }
 798         free(name);
 799         return val;
 800 }
 801
 802 /*
 803  * Does the ---/+++ line have the POSIX timestamp after the last HT?
 804  * GNU diff puts epoch there to signal a creation/deletion event.  Is
 805  * this such a timestamp?
 806  */
 807 static int has_epoch_timestamp(const char *nameline)
 808 {
 809         /*
 810          * We are only interested in epoch timestamp; any non-zero
 811          * fraction cannot be one, hence "(\.0+)?" in the regexp below.
 812          * For the same reason, the date must be either 1969-12-31 or
 813          * 1970-01-01, and the seconds part must be "00".
 814          */
 815         const char stamp_regexp[] =
 816                 "^(1969-12-31|1970-01-01)"
 817                 " "
 818                 "[0-2][0-9]:[0-5][0-9]:00(\\.0+)?"
 819                 " "
 820                 "([-+][0-2][0-9]:?[0-5][0-9])\n";
 821         const char *timestamp = NULL, *cp, *colon;
 822         static regex_t *stamp;
 823         regmatch_t m[10];
 824         int zoneoffset;
 825         int hourminute;
 826         int status;
 827
 828         for (cp = nameline; *cp != '\n'; cp++) {
 829                 if (*cp == '\t')
 830                         timestamp = cp + 1;
 831         }
 832         if (!timestamp)
 833                 return 0;
 834         if (!stamp) {
 835                 stamp = xmalloc(sizeof(*stamp));
 836                 if (regcomp(stamp, stamp_regexp, REG_EXTENDED)) {
 837                         warning(_("Cannot prepare timestamp regexp %s"),
 838                                 stamp_regexp);
 839                         return 0;
 840                 }
 841         }
 842
 843         status = regexec(stamp, timestamp, ARRAY_SIZE(m), m, 0);
 844         if (status) {
 845                 if (status != REG_NOMATCH)
 846                         warning(_("regexec returned %d for input: %s"),
 847                                 status, timestamp);
 848                 return 0;
 849         }
 850
 851         zoneoffset = strtol(timestamp + m[3].rm_so + 1, (char **) &colon, 10);
 852         if (*colon == ':')
 853                 zoneoffset = zoneoffset * 60 + strtol(colon + 1, NULL, 10);
 854         else
 855                 zoneoffset = (zoneoffset / 100) * 60 + (zoneoffset % 100);
 856         if (timestamp[m[3].rm_so] == '-')
 857                 zoneoffset = -zoneoffset;
 858
 859         /*
 860          * YYYY-MM-DD hh:mm:ss must be from either 1969-12-31
 861          * (west of GMT) or 1970-01-01 (east of GMT)
 862          */
 863         if ((zoneoffset < 0 && memcmp(timestamp, "1969-12-31", 10)) ||
 864             (0 <= zoneoffset && memcmp(timestamp, "1970-01-01", 10)))
 865                 return 0;
 866
 867         hourminute = (strtol(timestamp + 11, NULL, 10) * 60 +
 868                       strtol(timestamp + 14, NULL, 10) -
 869                       zoneoffset);
 870
 871         return ((zoneoffset < 0 && hourminute == 1440) ||
 872                 (0 <= zoneoffset && !hourminute));
 873 }
 874
 875 /*
 876  * Get the name etc info from the ---/+++ lines of a traditional patch header
 877  *
 878  * FIXME! The end-of-filename heuristics are kind of screwy. For existing
 879  * files, we can happily check the index for a match, but for creating a
 880  * new file we should try to match whatever "patch" does. I have no idea.
 881  */
 882 static int parse_traditional_patch(struct apply_state *state,
 883                                    const char *first,
 884                                    const char *second,
 885                                    struct patch *patch)
 886 {
 887         char *name;
 888
 889         first += 4;     /* skip "--- " */
 890         second += 4;    /* skip "+++ " */
 891         if (!state->p_value_known) {
 892                 int p, q;
 893                 p = guess_p_value(state, first);
 894                 q = guess_p_value(state, second);
 895                 if (p < 0) p = q;
 896                 if (0 <= p && p == q) {
 897                         state->p_value = p;
 898                         state->p_value_known = 1;
 899                 }
 900         }
 901         if (is_dev_null(first)) {
 902                 patch->is_new = 1;
 903                 patch->is_delete = 0;
 904                 name = find_name_traditional(state, second, NULL, state->p_value);
 905                 patch->new_name = name;
 906         } else if (is_dev_null(second)) {
 907                 patch->is_new = 0;
 908                 patch->is_delete = 1;
 909                 name = find_name_traditional(state, first, NULL, state->p_value);
 910                 patch->old_name = name;
 911         } else {
 912                 char *first_name;
 913                 first_name = find_name_traditional(state, first, NULL, state->p_value);
 914                 name = find_name_traditional(state, second, first_name, state->p_value);
 915                 free(first_name);
 916                 if (has_epoch_timestamp(first)) {
 917                         patch->is_new = 1;
 918                         patch->is_delete = 0;
 919                         patch->new_name = name;
 920                 } else if (has_epoch_timestamp(second)) {
 921                         patch->is_new = 0;
 922                         patch->is_delete = 1;
 923                         patch->old_name = name;
 924                 } else {
 925                         patch->old_name = name;
 926                         patch->new_name = xstrdup_or_null(name);
 927                 }
 928         }
 929         if (!name)
 930                 return error(_("unable to find filename in patch at line %d"), state->linenr);
 931
 932         return 0;
 933 }
 934
 935 static int gitdiff_hdrend(struct apply_state *state,
 936                           const char *line,
 937                           struct patch *patch)
 938 {
 939         return 1;
 940 }
 941
 942 /*
 943  * We're anal about diff header consistency, to make
 944  * sure that we don't end up having strange ambiguous
 945  * patches floating around.
 946  *
 947  * As a result, gitdiff_{old|new}name() will check
 948  * their names against any previous information, just
 949  * to make sure..
 950  */
 951 #define DIFF_OLD_NAME 0
 952 #define DIFF_NEW_NAME 1
 953
 954 static int gitdiff_verify_name(struct apply_state *state,
 955                                const char *line,
 956                                int isnull,
 957                                char **name,
 958                                int side)
 959 {
 960         if (!*name && !isnull) {
 961                 *name = find_name(state, line, NULL, state->p_value, TERM_TAB);
 962                 return 0;
 963         }
 964
 965         if (*name) {
 966                 char *another;
 967                 if (isnull)
 968                         return error(_("git apply: bad git-diff - expected /dev/null, got %s on line %d"),
 969                                      *name, state->linenr);
 970                 another = find_name(state, line, NULL, state->p_value, TERM_TAB);
 971                 if (!another || strcmp(another, *name)) {
 972                         free(another);
 973                         return error((side == DIFF_NEW_NAME) ?
 974                             _("git apply: bad git-diff - inconsistent new filename on line %d") :
 975                             _("git apply: bad git-diff - inconsistent old filename on line %d"), state->linenr);
 976                 }
 977                 free(another);
 978         } else {
 979                 if (!starts_with(line, "/dev/null\n"))
 980                         return error(_("git apply: bad git-diff - expected /dev/null on line %d"), state->linenr);
 981         }
 982
 983         return 0;
 984 }
 985
 986 static int gitdiff_oldname(struct apply_state *state,
 987                            const char *line,
 988                            struct patch *patch)
 989 {
 990         return gitdiff_verify_name(state, line,
 991                                    patch->is_new, &patch->old_name,
 992                                    DIFF_OLD_NAME);
 993 }
 994
 995 static int gitdiff_newname(struct apply_state *state,
 996                            const char *line,
 997                            struct patch *patch)
 998 {
 999         return gitdiff_verify_name(state, line,
1000                                    patch->is_delete, &patch->new_name,
1001                                    DIFF_NEW_NAME);
1002 }
1003
1004 static int parse_mode_line(const char *line, int linenr, unsigned int *mode)
1005 {
1006         char *end;
1007         *mode = strtoul(line, &end, 8);
1008         if (end == line || !isspace(*end))
1009                 return error(_("invalid mode on line %d: %s"), linenr, line);
1010         return 0;
1011 }
1012
1013 static int gitdiff_oldmode(struct apply_state *state,
1014                            const char *line,
1015                            struct patch *patch)
1016 {
1017         return parse_mode_line(line, state->linenr, &patch->old_mode);
1018 }
1019
1020 static int gitdiff_newmode(struct apply_state *state,
1021                            const char *line,
1022                            struct patch *patch)
1023 {
1024         return parse_mode_line(line, state->linenr, &patch->new_mode);
1025 }
1026
1027 static int gitdiff_delete(struct apply_state *state,
1028                           const char *line,
1029                           struct patch *patch)
1030 {
1031         patch->is_delete = 1;
1032         free(patch->old_name);
1033         patch->old_name = xstrdup_or_null(patch->def_name);
1034         return gitdiff_oldmode(state, line, patch);
1035 }
1036
1037 static int gitdiff_newfile(struct apply_state *state,
1038                            const char *line,
1039                            struct patch *patch)
1040 {
1041         patch->is_new = 1;
1042         free(patch->new_name);
1043         patch->new_name = xstrdup_or_null(patch->def_name);
1044         return gitdiff_newmode(state, line, patch);
1045 }
1046
1047 static int gitdiff_copysrc(struct apply_state *state,
1048                            const char *line,
1049                            struct patch *patch)
1050 {
1051         patch->is_copy = 1;
1052         free(patch->old_name);
1053         patch->old_name = find_name(state, line, NULL, state->p_value ? state->p_value - 1 : 0, 0);
1054         return 0;
1055 }
1056
1057 static int gitdiff_copydst(struct apply_state *state,
1058                            const char *line,
1059                            struct patch *patch)
1060 {
1061         patch->is_copy = 1;
1062         free(patch->new_name);
1063         patch->new_name = find_name(state, line, NULL, state->p_value ? state->p_value - 1 : 0, 0);
1064         return 0;
1065 }
1066
1067 static int gitdiff_renamesrc(struct apply_state *state,
1068                              const char *line,
1069                              struct patch *patch)
1070 {
1071         patch->is_rename = 1;
1072         free(patch->old_name);
1073         patch->old_name = find_name(state, line, NULL, state->p_value ? state->p_value - 1 : 0, 0);
1074         return 0;
1075 }
1076
1077 static int gitdiff_renamedst(struct apply_state *state,
1078                              const char *line,
1079                              struct patch *patch)
1080 {
1081         patch->is_rename = 1;
1082         free(patch->new_name);
1083         patch->new_name = find_name(state, line, NULL, state->p_value ? state->p_value - 1 : 0, 0);
1084         return 0;
1085 }
1086
1087 static int gitdiff_similarity(struct apply_state *state,
1088                               const char *line,
1089                               struct patch *patch)
1090 {
1091         unsigned long val = strtoul(line, NULL, 10);
1092         if (val <= 100)
1093                 patch->score = val;
1094         return 0;
1095 }
1096
1097 static int gitdiff_dissimilarity(struct apply_state *state,
1098                                  const char *line,
1099                                  struct patch *patch)
1100 {
1101         unsigned long val = strtoul(line, NULL, 10);
1102         if (val <= 100)
1103                 patch->score = val;
1104         return 0;
1105 }
1106
1107 static int gitdiff_index(struct apply_state *state,
1108                          const char *line,
1109                          struct patch *patch)
1110 {
1111         /*
1112          * index line is N hexadecimal, "..", N hexadecimal,
1113          * and optional space with octal mode.
1114          */
1115         const char *ptr, *eol;
1116         int len;
1117
1118         ptr = strchr(line, '.');
1119         if (!ptr || ptr[1] != '.' || 40 < ptr - line)
1120                 return 0;
1121         len = ptr - line;
1122         memcpy(patch->old_sha1_prefix, line, len);
1123         patch->old_sha1_prefix[len] = 0;
1124
1125         line = ptr + 2;
1126         ptr = strchr(line, ' ');
1127         eol = strchrnul(line, '\n');
1128
1129         if (!ptr || eol < ptr)
1130                 ptr = eol;
1131         len = ptr - line;
1132
1133         if (40 < len)
1134                 return 0;
1135         memcpy(patch->new_sha1_prefix, line, len);
1136         patch->new_sha1_prefix[len] = 0;
1137         if (*ptr == ' ')
1138                 return gitdiff_oldmode(state, ptr + 1, patch);
1139         return 0;
1140 }
1141
1142 /*
1143  * This is normal for a diff that doesn't change anything: we'll fall through
1144  * into the next diff. Tell the parser to break out.
1145  */
1146 static int gitdiff_unrecognized(struct apply_state *state,
1147                                 const char *line,
1148                                 struct patch *patch)
1149 {
1150         return 1;
1151 }
1152
1153 /*
1154  * Skip p_value leading components from "line"; as we do not accept
1155  * absolute paths, return NULL in that case.
1156  */
1157 static const char *skip_tree_prefix(struct apply_state *state,
1158                                     const char *line,
1159                                     int llen)
1160 {
1161         int nslash;
1162         int i;
1163
1164         if (!state->p_value)
1165                 return (llen && line[0] == '/') ? NULL : line;
1166
1167         nslash = state->p_value;
1168         for (i = 0; i < llen; i++) {
1169                 int ch = line[i];
1170                 if (ch == '/' && --nslash <= 0)
1171                         return (i == 0) ? NULL : &line[i + 1];
1172         }
1173         return NULL;
1174 }
1175
1176 /*
1177  * This is to extract the same name that appears on "diff --git"
1178  * line.  We do not find and return anything if it is a rename
1179  * patch, and it is OK because we will find the name elsewhere.
1180  * We need to reliably find name only when it is mode-change only,
1181  * creation or deletion of an empty file.  In any of these cases,
1182  * both sides are the same name under a/ and b/ respectively.
1183  */
1184 static char *git_header_name(struct apply_state *state,
1185                              const char *line,
1186                              int llen)
1187 {
1188         const char *name;
1189         const char *second = NULL;
1190         size_t len, line_len;
1191
1192         line += strlen("diff --git ");
1193         llen -= strlen("diff --git ");
1194
1195         if (*line == '"') {
1196                 const char *cp;
1197                 struct strbuf first = STRBUF_INIT;
1198                 struct strbuf sp = STRBUF_INIT;
1199
1200                 if (unquote_c_style(&first, line, &second))
1201                         goto free_and_fail1;
1202
1203                 /* strip the a/b prefix including trailing slash */
1204                 cp = skip_tree_prefix(state, first.buf, first.len);
1205                 if (!cp)
1206                         goto free_and_fail1;
1207                 strbuf_remove(&first, 0, cp - first.buf);
1208
1209                 /*
1210                  * second points at one past closing dq of name.
1211                  * find the second name.
1212                  */
1213                 while ((second < line + llen) && isspace(*second))
1214                         second++;
1215
1216                 if (line + llen <= second)
1217                         goto free_and_fail1;
1218                 if (*second == '"') {
1219                         if (unquote_c_style(&sp, second, NULL))
1220                                 goto free_and_fail1;
1221                         cp = skip_tree_prefix(state, sp.buf, sp.len);
1222                         if (!cp)
1223                                 goto free_and_fail1;
1224                         /* They must match, otherwise ignore */
1225                         if (strcmp(cp, first.buf))
1226                                 goto free_and_fail1;
1227                         strbuf_release(&sp);
1228                         return strbuf_detach(&first, NULL);
1229                 }
1230
1231                 /* unquoted second */
1232                 cp = skip_tree_prefix(state, second, line + llen - second);
1233                 if (!cp)
1234                         goto free_and_fail1;
1235                 if (line + llen - cp != first.len ||
1236                     memcmp(first.buf, cp, first.len))
1237                         goto free_and_fail1;
1238                 return strbuf_detach(&first, NULL);
1239
1240         free_and_fail1:
1241                 strbuf_release(&first);
1242                 strbuf_release(&sp);
1243                 return NULL;
1244         }
1245
1246         /* unquoted first name */
1247         name = skip_tree_prefix(state, line, llen);
1248         if (!name)
1249                 return NULL;
1250
1251         /*
1252          * since the first name is unquoted, a dq if exists must be
1253          * the beginning of the second name.
1254          */
1255         for (second = name; second < line + llen; second++) {
1256                 if (*second == '"') {
1257                         struct strbuf sp = STRBUF_INIT;
1258                         const char *np;
1259
1260                         if (unquote_c_style(&sp, second, NULL))
1261                                 goto free_and_fail2;
1262
1263                         np = skip_tree_prefix(state, sp.buf, sp.len);
1264                         if (!np)
1265                                 goto free_and_fail2;
1266
1267                         len = sp.buf + sp.len - np;
1268                         if (len < second - name &&
1269                             !strncmp(np, name, len) &&
1270                             isspace(name[len])) {
1271                                 /* Good */
1272                                 strbuf_remove(&sp, 0, np - sp.buf);
1273                                 return strbuf_detach(&sp, NULL);
1274                         }
1275
1276                 free_and_fail2:
1277                         strbuf_release(&sp);
1278                         return NULL;
1279                 }
1280         }
1281
1282         /*
1283          * Accept a name only if it shows up twice, exactly the same
1284          * form.
1285          */
1286         second = strchr(name, '\n');
1287         if (!second)
1288                 return NULL;
1289         line_len = second - name;
1290         for (len = 0 ; ; len++) {
1291                 switch (name[len]) {
1292                 default:
1293                         continue;
1294                 case '\n':
1295                         return NULL;
1296                 case '\t': case ' ':
1297                         /*
1298                          * Is this the separator between the preimage
1299                          * and the postimage pathname?  Again, we are
1300                          * only interested in the case where there is
1301                          * no rename, as this is only to set def_name
1302                          * and a rename patch has the names elsewhere
1303                          * in an unambiguous form.
1304                          */
1305                         if (!name[len + 1])
1306                                 return NULL; /* no postimage name */
1307                         second = skip_tree_prefix(state, name + len + 1,
1308                                                   line_len - (len + 1));
1309                         if (!second)
1310                                 return NULL;
1311                         /*
1312                          * Does len bytes starting at "name" and "second"
1313                          * (that are separated by one HT or SP we just
1314                          * found) exactly match?
1315                          */
1316                         if (second[len] == '\n' && !strncmp(name, second, len))
1317                                 return xmemdupz(name, len);
1318                 }
1319         }
1320 }
1321
1322 static int check_header_line(struct apply_state *state, struct patch *patch)
1323 {
1324         int extensions = (patch->is_delete == 1) + (patch->is_new == 1) +
1325                          (patch->is_rename == 1) + (patch->is_copy == 1);
1326         if (extensions > 1)
1327                 return error(_("inconsistent header lines %d and %d"),
1328                              patch->extension_linenr, state->linenr);
1329         if (extensions && !patch->extension_linenr)
1330                 patch->extension_linenr = state->linenr;
1331         return 0;
1332 }
1333
1334 /* Verify that we recognize the lines following a git header */
1335 static int parse_git_header(struct apply_state *state,
1336                             const char *line,
1337                             int len,
1338                             unsigned int size,
1339                             struct patch *patch)
1340 {
1341         unsigned long offset;
1342
1343         /* A git diff has explicit new/delete information, so we don't guess */
1344         patch->is_new = 0;
1345         patch->is_delete = 0;
1346
1347         /*
1348          * Some things may not have the old name in the
1349          * rest of the headers anywhere (pure mode changes,
1350          * or removing or adding empty files), so we get
1351          * the default name from the header.
1352          */
1353         patch->def_name = git_header_name(state, line, len);
1354         if (patch->def_name && state->root.len) {
1355                 char *s = xstrfmt("%s%s", state->root.buf, patch->def_name);
1356                 free(patch->def_name);
1357                 patch->def_name = s;
1358         }
1359
1360         line += len;
1361         size -= len;
1362         state->linenr++;
1363         for (offset = len ; size > 0 ; offset += len, size -= len, line += len, state->linenr++) {
1364                 static const struct opentry {
1365                         const char *str;
1366                         int (*fn)(struct apply_state *, const char *, struct patch *);
1367                 } optable[] = {
1368                         { "@@ -", gitdiff_hdrend },
1369                         { "--- ", gitdiff_oldname },
1370                         { "+++ ", gitdiff_newname },
1371                         { "old mode ", gitdiff_oldmode },
1372                         { "new mode ", gitdiff_newmode },
1373                         { "deleted file mode ", gitdiff_delete },
1374                         { "new file mode ", gitdiff_newfile },
1375                         { "copy from ", gitdiff_copysrc },
1376                         { "copy to ", gitdiff_copydst },
1377                         { "rename old ", gitdiff_renamesrc },
1378                         { "rename new ", gitdiff_renamedst },
1379                         { "rename from ", gitdiff_renamesrc },
1380                         { "rename to ", gitdiff_renamedst },
1381                         { "similarity index ", gitdiff_similarity },
1382                         { "dissimilarity index ", gitdiff_dissimilarity },
1383                         { "index ", gitdiff_index },
1384                         { "", gitdiff_unrecognized },
1385                 };
1386                 int i;
1387
1388                 len = linelen(line, size);
1389                 if (!len || line[len-1] != '\n')
1390                         break;
1391                 for (i = 0; i < ARRAY_SIZE(optable); i++) {
1392                         const struct opentry *p = optable + i;
1393                         int oplen = strlen(p->str);
1394                         int res;
1395                         if (len < oplen || memcmp(p->str, line, oplen))
1396                                 continue;
1397                         res = p->fn(state, line + oplen, patch);
1398                         if (res < 0)
1399                                 return -1;
1400                         if (check_header_line(state, patch))
1401                                 return -1;
1402                         if (res > 0)
1403                                 return offset;
1404                         break;
1405                 }
1406         }
1407
1408         return offset;
1409 }
1410
1411 static int parse_num(const char *line, unsigned long *p)
1412 {
1413         char *ptr;
1414
1415         if (!isdigit(*line))
1416                 return 0;
1417         *p = strtoul(line, &ptr, 10);
1418         return ptr - line;
1419 }
1420
1421 static int parse_range(const char *line, int len, int offset, const char *expect,
1422                        unsigned long *p1, unsigned long *p2)
1423 {
1424         int digits, ex;
1425
1426         if (offset < 0 || offset >= len)
1427                 return -1;
1428         line += offset;
1429         len -= offset;
1430
1431         digits = parse_num(line, p1);
1432         if (!digits)
1433                 return -1;
1434
1435         offset += digits;
1436         line += digits;
1437         len -= digits;
1438
1439         *p2 = 1;
1440         if (*line == ',') {
1441                 digits = parse_num(line+1, p2);
1442                 if (!digits)
1443                         return -1;
1444
1445                 offset += digits+1;
1446                 line += digits+1;
1447                 len -= digits+1;
1448         }
1449
1450         ex = strlen(expect);
1451         if (ex > len)
1452                 return -1;
1453         if (memcmp(line, expect, ex))
1454                 return -1;
1455
1456         return offset + ex;
1457 }
1458
1459 static void recount_diff(const char *line, int size, struct fragment *fragment)
1460 {
1461         int oldlines = 0, newlines = 0, ret = 0;
1462
1463         if (size < 1) {
1464                 warning("recount: ignore empty hunk");
1465                 return;
1466         }
1467
1468         for (;;) {
1469                 int len = linelen(line, size);
1470                 size -= len;
1471                 line += len;
1472
1473                 if (size < 1)
1474                         break;
1475
1476                 switch (*line) {
1477                 case ' ': case '\n':
1478                         newlines++;
1479                         /* fall through */
1480                 case '-':
1481                         oldlines++;
1482                         continue;
1483                 case '+':
1484                         newlines++;
1485                         continue;
1486                 case '\\':
1487                         continue;
1488                 case '@':
1489                         ret = size < 3 || !starts_with(line, "@@ ");
1490                         break;
1491                 case 'd':
1492                         ret = size < 5 || !starts_with(line, "diff ");
1493                         break;
1494                 default:
1495                         ret = -1;
1496                         break;
1497                 }
1498                 if (ret) {
1499                         warning(_("recount: unexpected line: %.*s"),
1500                                 (int)linelen(line, size), line);
1501                         return;
1502                 }
1503                 break;
1504         }
1505         fragment->oldlines = oldlines;
1506         fragment->newlines = newlines;
1507 }
1508
1509 /*
1510  * Parse a unified diff fragment header of the
1511  * form "@@ -a,b +c,d @@"
1512  */
1513 static int parse_fragment_header(const char *line, int len, struct fragment *fragment)
1514 {
1515         int offset;
1516
1517         if (!len || line[len-1] != '\n')
1518                 return -1;
1519
1520         /* Figure out the number of lines in a fragment */
1521         offset = parse_range(line, len, 4, " +", &fragment->oldpos, &fragment->oldlines);
1522         offset = parse_range(line, len, offset, " @@", &fragment->newpos, &fragment->newlines);
1523
1524         return offset;
1525 }
1526
1527 /*
1528  * Find file diff header
1529  *
1530  * Returns:
1531  *  -1 if no header was found
1532  *  -128 in case of error
1533  *   the size of the header in bytes (called "offset") otherwise
1534  */
1535 static int find_header(struct apply_state *state,
1536                        const char *line,
1537                        unsigned long size,
1538                        int *hdrsize,
1539                        struct patch *patch)
1540 {
1541         unsigned long offset, len;
1542
1543         patch->is_toplevel_relative = 0;
1544         patch->is_rename = patch->is_copy = 0;
1545         patch->is_new = patch->is_delete = -1;
1546         patch->old_mode = patch->new_mode = 0;
1547         patch->old_name = patch->new_name = NULL;
1548         for (offset = 0; size > 0; offset += len, size -= len, line += len, state->linenr++) {
1549                 unsigned long nextlen;
1550
1551                 len = linelen(line, size);
1552                 if (!len)
1553                         break;
1554
1555                 /* Testing this early allows us to take a few shortcuts.. */
1556                 if (len < 6)
1557                         continue;
1558
1559                 /*
1560                  * Make sure we don't find any unconnected patch fragments.
1561                  * That's a sign that we didn't find a header, and that a
1562                  * patch has become corrupted/broken up.
1563                  */
1564                 if (!memcmp("@@ -", line, 4)) {
1565                         struct fragment dummy;
1566                         if (parse_fragment_header(line, len, &dummy) < 0)
1567                                 continue;
1568                         error(_("patch fragment without header at line %d: %.*s"),
1569                                      state->linenr, (int)len-1, line);
1570                         return -128;
1571                 }
1572
1573                 if (size < len + 6)
1574                         break;
1575
1576                 /*
1577                  * Git patch? It might not have a real patch, just a rename
1578                  * or mode change, so we handle that specially
1579                  */
1580                 if (!memcmp("diff --git ", line, 11)) {
1581                         int git_hdr_len = parse_git_header(state, line, len, size, patch);
1582                         if (git_hdr_len < 0)
1583                                 return -128;
1584                         if (git_hdr_len <= len)
1585                                 continue;
1586                         if (!patch->old_name && !patch->new_name) {
1587                                 if (!patch->def_name) {
1588                                         error(Q_("git diff header lacks filename information when removing "
1589                                                         "%d leading pathname component (line %d)",
1590                                                         "git diff header lacks filename information when removing "
1591                                                         "%d leading pathname components (line %d)",
1592                                                         state->p_value),
1593                                                      state->p_value, state->linenr);
1594                                         return -128;
1595                                 }
1596                                 patch->old_name = xstrdup(patch->def_name);
1597                                 patch->new_name = xstrdup(patch->def_name);
1598                         }
1599                         if ((!patch->new_name && !patch->is_delete) ||
1600                             (!patch->old_name && !patch->is_new)) {
1601                                 error(_("git diff header lacks filename information "
1602                                              "(line %d)"), state->linenr);
1603                                 return -128;
1604                         }
1605                         patch->is_toplevel_relative = 1;
1606                         *hdrsize = git_hdr_len;
1607                         return offset;
1608                 }
1609
1610                 /* --- followed by +++ ? */
1611                 if (memcmp("--- ", line,  4) || memcmp("+++ ", line + len, 4))
1612                         continue;
1613
1614                 /*
1615                  * We only accept unified patches, so we want it to
1616                  * at least have "@@ -a,b +c,d @@\n", which is 14 chars
1617                  * minimum ("@@ -0,0 +1 @@\n" is the shortest).
1618                  */
1619                 nextlen = linelen(line + len, size - len);
1620                 if (size < nextlen + 14 || memcmp("@@ -", line + len + nextlen, 4))
1621                         continue;
1622
1623                 /* Ok, we'll consider it a patch */
1624                 if (parse_traditional_patch(state, line, line+len, patch))
1625                         return -128;
1626                 *hdrsize = len + nextlen;
1627                 state->linenr += 2;
1628                 return offset;
1629         }
1630         return -1;
1631 }
1632
1633 static void record_ws_error(struct apply_state *state,
1634                             unsigned result,
1635                             const char *line,
1636                             int len,
1637                             int linenr)
1638 {
1639         char *err;
1640
1641         if (!result)
1642                 return;
1643
1644         state->whitespace_error++;
1645         if (state->squelch_whitespace_errors &&
1646             state->squelch_whitespace_errors < state->whitespace_error)
1647                 return;
1648
1649         err = whitespace_error_string(result);
1650         if (state->apply_verbosity > verbosity_silent)
1651                 fprintf(stderr, "%s:%d: %s.\n%.*s\n",
1652                         state->patch_input_file, linenr, err, len, line);
1653         free(err);
1654 }
1655
1656 static void check_whitespace(struct apply_state *state,
1657                              const char *line,
1658                              int len,
1659                              unsigned ws_rule)
1660 {
1661         unsigned result = ws_check(line + 1, len - 1, ws_rule);
1662
1663         record_ws_error(state, result, line + 1, len - 2, state->linenr);
1664 }
1665
1666 /*
1667  * Check if the patch has context lines with CRLF or
1668  * the patch wants to remove lines with CRLF.
1669  */
1670 static void check_old_for_crlf(struct patch *patch, const char *line, int len)
1671 {
1672         if (len >= 2 && line[len-1] == '\n' && line[len-2] == '\r') {
1673                 patch->ws_rule |= WS_CR_AT_EOL;
1674                 patch->crlf_in_old = 1;
1675         }
1676 }
1677
1678
1679 /*
1680  * Parse a unified diff. Note that this really needs to parse each
1681  * fragment separately, since the only way to know the difference
1682  * between a "---" that is part of a patch, and a "---" that starts
1683  * the next patch is to look at the line counts..
1684  */
1685 static int parse_fragment(struct apply_state *state,
1686                           const char *line,
1687                           unsigned long size,
1688                           struct patch *patch,
1689                           struct fragment *fragment)
1690 {
1691         int added, deleted;
1692         int len = linelen(line, size), offset;
1693         unsigned long oldlines, newlines;
1694         unsigned long leading, trailing;
1695
1696         offset = parse_fragment_header(line, len, fragment);
1697         if (offset < 0)
1698                 return -1;
1699         if (offset > 0 && patch->recount)
1700                 recount_diff(line + offset, size - offset, fragment);
1701         oldlines = fragment->oldlines;
1702         newlines = fragment->newlines;
1703         leading = 0;
1704         trailing = 0;
1705
1706         /* Parse the thing.. */
1707         line += len;
1708         size -= len;
1709         state->linenr++;
1710         added = deleted = 0;
1711         for (offset = len;
1712              0 < size;
1713              offset += len, size -= len, line += len, state->linenr++) {
1714                 if (!oldlines && !newlines)
1715                         break;
1716                 len = linelen(line, size);
1717                 if (!len || line[len-1] != '\n')
1718                         return -1;
1719                 switch (*line) {
1720                 default:
1721                         return -1;
1722                 case '\n': /* newer GNU diff, an empty context line */
1723                 case ' ':
1724                         oldlines--;
1725                         newlines--;
1726                         if (!deleted && !added)
1727                                 leading++;
1728                         trailing++;
1729                         check_old_for_crlf(patch, line, len);
1730                         if (!state->apply_in_reverse &&
1731                             state->ws_error_action == correct_ws_error)
1732                                 check_whitespace(state, line, len, patch->ws_rule);
1733                         break;
1734                 case '-':
1735                         if (!state->apply_in_reverse)
1736                                 check_old_for_crlf(patch, line, len);
1737                         if (state->apply_in_reverse &&
1738                             state->ws_error_action != nowarn_ws_error)
1739                                 check_whitespace(state, line, len, patch->ws_rule);
1740                         deleted++;
1741                         oldlines--;
1742                         trailing = 0;
1743                         break;
1744                 case '+':
1745                         if (state->apply_in_reverse)
1746                                 check_old_for_crlf(patch, line, len);
1747                         if (!state->apply_in_reverse &&
1748                             state->ws_error_action != nowarn_ws_error)
1749                                 check_whitespace(state, line, len, patch->ws_rule);
1750                         added++;
1751                         newlines--;
1752                         trailing = 0;
1753                         break;
1754
1755                 /*
1756                  * We allow "\ No newline at end of file". Depending
1757                  * on locale settings when the patch was produced we
1758                  * don't know what this line looks like. The only
1759                  * thing we do know is that it begins with "\ ".
1760                  * Checking for 12 is just for sanity check -- any
1761                  * l10n of "\ No newline..." is at least that long.
1762                  */
1763                 case '\\':
1764                         if (len < 12 || memcmp(line, "\\ ", 2))
1765                                 return -1;
1766                         break;
1767                 }
1768         }
1769         if (oldlines || newlines)
1770                 return -1;
1771         if (!deleted && !added)
1772                 return -1;
1773
1774         fragment->leading = leading;
1775         fragment->trailing = trailing;
1776
1777         /*
1778          * If a fragment ends with an incomplete line, we failed to include
1779          * it in the above loop because we hit oldlines == newlines == 0
1780          * before seeing it.
1781          */
1782         if (12 < size && !memcmp(line, "\\ ", 2))
1783                 offset += linelen(line, size);
1784
1785         patch->lines_added += added;
1786         patch->lines_deleted += deleted;
1787
1788         if (0 < patch->is_new && oldlines)
1789                 return error(_("new file depends on old contents"));
1790         if (0 < patch->is_delete && newlines)
1791                 return error(_("deleted file still has contents"));
1792         return offset;
1793 }
1794
1795 /*
1796  * We have seen "diff --git a/... b/..." header (or a traditional patch
1797  * header).  Read hunks that belong to this patch into fragments and hang
1798  * them to the given patch structure.
1799  *
1800  * The (fragment->patch, fragment->size) pair points into the memory given
1801  * by the caller, not a copy, when we return.
1802  *
1803  * Returns:
1804  *   -1 in case of error,
1805  *   the number of bytes in the patch otherwise.
1806  */
1807 static int parse_single_patch(struct apply_state *state,
1808                               const char *line,
1809                               unsigned long size,
1810                               struct patch *patch)
1811 {
1812         unsigned long offset = 0;
1813         unsigned long oldlines = 0, newlines = 0, context = 0;
1814         struct fragment **fragp = &patch->fragments;
1815
1816         while (size > 4 && !memcmp(line, "@@ -", 4)) {
1817                 struct fragment *fragment;
1818                 int len;
1819
1820                 fragment = xcalloc(1, sizeof(*fragment));
1821                 fragment->linenr = state->linenr;
1822                 len = parse_fragment(state, line, size, patch, fragment);
1823                 if (len <= 0) {
1824                         free(fragment);
1825                         return error(_("corrupt patch at line %d"), state->linenr);
1826                 }
1827                 fragment->patch = line;
1828                 fragment->size = len;
1829                 oldlines += fragment->oldlines;
1830                 newlines += fragment->newlines;
1831                 context += fragment->leading + fragment->trailing;
1832
1833                 *fragp = fragment;
1834                 fragp = &fragment->next;
1835
1836                 offset += len;
1837                 line += len;
1838                 size -= len;
1839         }
1840
1841         /*
1842          * If something was removed (i.e. we have old-lines) it cannot
1843          * be creation, and if something was added it cannot be
1844          * deletion.  However, the reverse is not true; --unified=0
1845          * patches that only add are not necessarily creation even
1846          * though they do not have any old lines, and ones that only
1847          * delete are not necessarily deletion.
1848          *
1849          * Unfortunately, a real creation/deletion patch do _not_ have
1850          * any context line by definition, so we cannot safely tell it
1851          * apart with --unified=0 insanity.  At least if the patch has
1852          * more than one hunk it is not creation or deletion.
1853          */
1854         if (patch->is_new < 0 &&
1855             (oldlines || (patch->fragments && patch->fragments->next)))
1856                 patch->is_new = 0;
1857         if (patch->is_delete < 0 &&
1858             (newlines || (patch->fragments && patch->fragments->next)))
1859                 patch->is_delete = 0;
1860
1861         if (0 < patch->is_new && oldlines)
1862                 return error(_("new file %s depends on old contents"), patch->new_name);
1863         if (0 < patch->is_delete && newlines)
1864                 return error(_("deleted file %s still has contents"), patch->old_name);
1865         if (!patch->is_delete && !newlines && context && state->apply_verbosity > verbosity_silent)
1866                 fprintf_ln(stderr,
1867                            _("** warning: "
1868                              "file %s becomes empty but is not deleted"),
1869                            patch->new_name);
1870
1871         return offset;
1872 }
1873
1874 static inline int metadata_changes(struct patch *patch)
1875 {
1876         return  patch->is_rename > 0 ||
1877                 patch->is_copy > 0 ||
1878                 patch->is_new > 0 ||
1879                 patch->is_delete ||
1880                 (patch->old_mode && patch->new_mode &&
1881                  patch->old_mode != patch->new_mode);
1882 }
1883
1884 static char *inflate_it(const void *data, unsigned long size,
1885                         unsigned long inflated_size)
1886 {
1887         git_zstream stream;
1888         void *out;
1889         int st;
1890
1891         memset(&stream, 0, sizeof(stream));
1892
1893         stream.next_in = (unsigned char *)data;
1894         stream.avail_in = size;
1895         stream.next_out = out = xmalloc(inflated_size);
1896         stream.avail_out = inflated_size;
1897         git_inflate_init(&stream);
1898         st = git_inflate(&stream, Z_FINISH);
1899         git_inflate_end(&stream);
1900         if ((st != Z_STREAM_END) || stream.total_out != inflated_size) {
1901                 free(out);
1902                 return NULL;
1903         }
1904         return out;
1905 }
1906
1907 /*
1908  * Read a binary hunk and return a new fragment; fragment->patch
1909  * points at an allocated memory that the caller must free, so
1910  * it is marked as "->free_patch = 1".
1911  */
1912 static struct fragment *parse_binary_hunk(struct apply_state *state,
1913                                           char **buf_p,
1914                                           unsigned long *sz_p,
1915                                           int *status_p,
1916                                           int *used_p)
1917 {
1918         /*
1919          * Expect a line that begins with binary patch method ("literal"
1920          * or "delta"), followed by the length of data before deflating.
1921          * a sequence of 'length-byte' followed by base-85 encoded data
1922          * should follow, terminated by a newline.
1923          *
1924          * Each 5-byte sequence of base-85 encodes up to 4 bytes,
1925          * and we would limit the patch line to 66 characters,
1926          * so one line can fit up to 13 groups that would decode
1927          * to 52 bytes max.  The length byte 'A'-'Z' corresponds
1928          * to 1-26 bytes, and 'a'-'z' corresponds to 27-52 bytes.
1929          */
1930         int llen, used;
1931         unsigned long size = *sz_p;
1932         char *buffer = *buf_p;
1933         int patch_method;
1934         unsigned long origlen;
1935         char *data = NULL;
1936         int hunk_size = 0;
1937         struct fragment *frag;
1938
1939         llen = linelen(buffer, size);
1940         used = llen;
1941
1942         *status_p = 0;
1943
1944         if (starts_with(buffer, "delta ")) {
1945                 patch_method = BINARY_DELTA_DEFLATED;
1946                 origlen = strtoul(buffer + 6, NULL, 10);
1947         }
1948         else if (starts_with(buffer, "literal ")) {
1949                 patch_method = BINARY_LITERAL_DEFLATED;
1950                 origlen = strtoul(buffer + 8, NULL, 10);
1951         }
1952         else
1953                 return NULL;
1954
1955         state->linenr++;
1956         buffer += llen;
1957         while (1) {
1958                 int byte_length, max_byte_length, newsize;
1959                 llen = linelen(buffer, size);
1960                 used += llen;
1961                 state->linenr++;
1962                 if (llen == 1) {
1963                         /* consume the blank line */
1964                         buffer++;
1965                         size--;
1966                         break;
1967                 }
1968                 /*
1969                  * Minimum line is "A00000\n" which is 7-byte long,
1970                  * and the line length must be multiple of 5 plus 2.
1971                  */
1972                 if ((llen < 7) || (llen-2) % 5)
1973                         goto corrupt;
1974                 max_byte_length = (llen - 2) / 5 * 4;
1975                 byte_length = *buffer;
1976                 if ('A' <= byte_length && byte_length <= 'Z')
1977                         byte_length = byte_length - 'A' + 1;
1978                 else if ('a' <= byte_length && byte_length <= 'z')
1979                         byte_length = byte_length - 'a' + 27;
1980                 else
1981                         goto corrupt;
1982                 /* if the input length was not multiple of 4, we would
1983                  * have filler at the end but the filler should never
1984                  * exceed 3 bytes
1985                  */
1986                 if (max_byte_length < byte_length ||
1987                     byte_length <= max_byte_length - 4)
1988                         goto corrupt;
1989                 newsize = hunk_size + byte_length;
1990                 data = xrealloc(data, newsize);
1991                 if (decode_85(data + hunk_size, buffer + 1, byte_length))
1992                         goto corrupt;
1993                 hunk_size = newsize;
1994                 buffer += llen;
1995                 size -= llen;
1996         }
1997
1998         frag = xcalloc(1, sizeof(*frag));
1999         frag->patch = inflate_it(data, hunk_size, origlen);
2000         frag->free_patch = 1;
2001         if (!frag->patch)
2002                 goto corrupt;
2003         free(data);
2004         frag->size = origlen;
2005         *buf_p = buffer;
2006         *sz_p = size;
2007         *used_p = used;
2008         frag->binary_patch_method = patch_method;
2009         return frag;
2010
2011  corrupt:
2012         free(data);
2013         *status_p = -1;
2014         error(_("corrupt binary patch at line %d: %.*s"),
2015               state->linenr-1, llen-1, buffer);
2016         return NULL;
2017 }
2018
2019 /*
2020  * Returns:
2021  *   -1 in case of error,
2022  *   the length of the parsed binary patch otherwise
2023  */
2024 static int parse_binary(struct apply_state *state,
2025                         char *buffer,
2026                         unsigned long size,
2027                         struct patch *patch)
2028 {
2029         /*
2030          * We have read "GIT binary patch\n"; what follows is a line
2031          * that says the patch method (currently, either "literal" or
2032          * "delta") and the length of data before deflating; a
2033          * sequence of 'length-byte' followed by base-85 encoded data
2034          * follows.
2035          *
2036          * When a binary patch is reversible, there is another binary
2037          * hunk in the same format, starting with patch method (either
2038          * "literal" or "delta") with the length of data, and a sequence
2039          * of length-byte + base-85 encoded data, terminated with another
2040          * empty line.  This data, when applied to the postimage, produces
2041          * the preimage.
2042          */
2043         struct fragment *forward;
2044         struct fragment *reverse;
2045         int status;
2046         int used, used_1;
2047
2048         forward = parse_binary_hunk(state, &buffer, &size, &status, &used);
2049         if (!forward && !status)
2050                 /* there has to be one hunk (forward hunk) */
2051                 return error(_("unrecognized binary patch at line %d"), state->linenr-1);
2052         if (status)
2053                 /* otherwise we already gave an error message */
2054                 return status;
2055
2056         reverse = parse_binary_hunk(state, &buffer, &size, &status, &used_1);
2057         if (reverse)
2058                 used += used_1;
2059         else if (status) {
2060                 /*
2061                  * Not having reverse hunk is not an error, but having
2062                  * a corrupt reverse hunk is.
2063                  */
2064                 free((void*) forward->patch);
2065                 free(forward);
2066                 return status;
2067         }
2068         forward->next = reverse;
2069         patch->fragments = forward;
2070         patch->is_binary = 1;
2071         return used;
2072 }
2073
2074 static void prefix_one(struct apply_state *state, char **name)
2075 {
2076         char *old_name = *name;
2077         if (!old_name)
2078                 return;
2079         *name = prefix_filename(state->prefix, *name);
2080         free(old_name);
2081 }
2082
2083 static void prefix_patch(struct apply_state *state, struct patch *p)
2084 {
2085         if (!state->prefix || p->is_toplevel_relative)
2086                 return;
2087         prefix_one(state, &p->new_name);
2088         prefix_one(state, &p->old_name);
2089 }
2090
2091 /*
2092  * include/exclude
2093  */
2094
2095 static void add_name_limit(struct apply_state *state,
2096                            const char *name,
2097                            int exclude)
2098 {
2099         struct string_list_item *it;
2100
2101         it = string_list_append(&state->limit_by_name, name);
2102         it->util = exclude ? NULL : (void *) 1;
2103 }
2104
2105 static int use_patch(struct apply_state *state, struct patch *p)
2106 {
2107         const char *pathname = p->new_name ? p->new_name : p->old_name;
2108         int i;
2109
2110         /* Paths outside are not touched regardless of "--include" */
2111         if (0 < state->prefix_length) {
2112                 int pathlen = strlen(pathname);
2113                 if (pathlen <= state->prefix_length ||
2114                     memcmp(state->prefix, pathname, state->prefix_length))
2115                         return 0;
2116         }
2117
2118         /* See if it matches any of exclude/include rule */
2119         for (i = 0; i < state->limit_by_name.nr; i++) {
2120                 struct string_list_item *it = &state->limit_by_name.items[i];
2121                 if (!wildmatch(it->string, pathname, 0))
2122                         return (it->util != NULL);
2123         }
2124
2125         /*
2126          * If we had any include, a path that does not match any rule is
2127          * not used.  Otherwise, we saw bunch of exclude rules (or none)
2128          * and such a path is used.
2129          */
2130         return !state->has_include;
2131 }
2132
2133 /*
2134  * Read the patch text in "buffer" that extends for "size" bytes; stop
2135  * reading after seeing a single patch (i.e. changes to a single file).
2136  * Create fragments (i.e. patch hunks) and hang them to the given patch.
2137  *
2138  * Returns:
2139  *   -1 if no header was found or parse_binary() failed,
2140  *   -128 on another error,
2141  *   the number of bytes consumed otherwise,
2142  *     so that the caller can call us again for the next patch.
2143  */
2144 static int parse_chunk(struct apply_state *state, char *buffer, unsigned long size, struct patch *patch)
2145 {
2146         int hdrsize, patchsize;
2147         int offset = find_header(state, buffer, size, &hdrsize, patch);
2148
2149         if (offset < 0)
2150                 return offset;
2151
2152         prefix_patch(state, patch);
2153
2154         if (!use_patch(state, patch))
2155                 patch->ws_rule = 0;
2156         else
2157                 patch->ws_rule = whitespace_rule(patch->new_name
2158                                                  ? patch->new_name
2159                                                  : patch->old_name);
2160
2161         patchsize = parse_single_patch(state,
2162                                        buffer + offset + hdrsize,
2163                                        size - offset - hdrsize,
2164                                        patch);
2165
2166         if (patchsize < 0)
2167                 return -128;
2168
2169         if (!patchsize) {
2170                 static const char git_binary[] = "GIT binary patch\n";
2171                 int hd = hdrsize + offset;
2172                 unsigned long llen = linelen(buffer + hd, size - hd);
2173
2174                 if (llen == sizeof(git_binary) - 1 &&
2175                     !memcmp(git_binary, buffer + hd, llen)) {
2176                         int used;
2177                         state->linenr++;
2178                         used = parse_binary(state, buffer + hd + llen,
2179                                             size - hd - llen, patch);
2180                         if (used < 0)
2181                                 return -1;
2182                         if (used)
2183                                 patchsize = used + llen;
2184                         else
2185                                 patchsize = 0;
2186                 }
2187                 else if (!memcmp(" differ\n", buffer + hd + llen - 8, 8)) {
2188                         static const char *binhdr[] = {
2189                                 "Binary files ",
2190                                 "Files ",
2191                                 NULL,
2192                         };
2193                         int i;
2194                         for (i = 0; binhdr[i]; i++) {
2195                                 int len = strlen(binhdr[i]);
2196                                 if (len < size - hd &&
2197                                     !memcmp(binhdr[i], buffer + hd, len)) {
2198                                         state->linenr++;
2199                                         patch->is_binary = 1;
2200                                         patchsize = llen;
2201                                         break;
2202                                 }
2203                         }
2204                 }
2205
2206                 /* Empty patch cannot be applied if it is a text patch
2207                  * without metadata change.  A binary patch appears
2208                  * empty to us here.
2209                  */
2210                 if ((state->apply || state->check) &&
2211                     (!patch->is_binary && !metadata_changes(patch))) {
2212                         error(_("patch with only garbage at line %d"), state->linenr);
2213                         return -128;
2214                 }
2215         }
2216
2217         return offset + hdrsize + patchsize;
2218 }
2219
2220 static void reverse_patches(struct patch *p)
2221 {
2222         for (; p; p = p->next) {
2223                 struct fragment *frag = p->fragments;
2224
2225                 SWAP(p->new_name, p->old_name);
2226                 SWAP(p->new_mode, p->old_mode);
2227                 SWAP(p->is_new, p->is_delete);
2228                 SWAP(p->lines_added, p->lines_deleted);
2229                 SWAP(p->old_sha1_prefix, p->new_sha1_prefix);
2230
2231                 for (; frag; frag = frag->next) {
2232                         SWAP(frag->newpos, frag->oldpos);
2233                         SWAP(frag->newlines, frag->oldlines);
2234                 }
2235         }
2236 }
2237
2238 static const char pluses[] =
2239 "++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++";
2240 static const char minuses[]=
2241 "----------------------------------------------------------------------";
2242
2243 static void show_stats(struct apply_state *state, struct patch *patch)
2244 {
2245         struct strbuf qname = STRBUF_INIT;
2246         char *cp = patch->new_name ? patch->new_name : patch->old_name;
2247         int max, add, del;
2248
2249         quote_c_style(cp, &qname, NULL, 0);
2250
2251         /*
2252          * "scale" the filename
2253          */
2254         max = state->max_len;
2255         if (max > 50)
2256                 max = 50;
2257
2258         if (qname.len > max) {
2259                 cp = strchr(qname.buf + qname.len + 3 - max, '/');
2260                 if (!cp)
2261                         cp = qname.buf + qname.len + 3 - max;
2262                 strbuf_splice(&qname, 0, cp - qname.buf, "...", 3);
2263         }
2264
2265         if (patch->is_binary) {
2266                 printf(" %-*s |  Bin\n", max, qname.buf);
2267                 strbuf_release(&qname);
2268                 return;
2269         }
2270
2271         printf(" %-*s |", max, qname.buf);
2272         strbuf_release(&qname);
2273
2274         /*
2275          * scale the add/delete
2276          */
2277         max = max + state->max_change > 70 ? 70 - max : state->max_change;
2278         add = patch->lines_added;
2279         del = patch->lines_deleted;
2280
2281         if (state->max_change > 0) {
2282                 int total = ((add + del) * max + state->max_change / 2) / state->max_change;
2283                 add = (add * max + state->max_change / 2) / state->max_change;
2284                 del = total - add;
2285         }
2286         printf("%5d %.*s%.*s\n", patch->lines_added + patch->lines_deleted,
2287                 add, pluses, del, minuses);
2288 }
2289
2290 static int read_old_data(struct stat *st, struct patch *patch,
2291                          const char *path, struct strbuf *buf)
2292 {
2293         enum safe_crlf safe_crlf = patch->crlf_in_old ?
2294                 SAFE_CRLF_KEEP_CRLF : SAFE_CRLF_RENORMALIZE;
2295         switch (st->st_mode & S_IFMT) {
2296         case S_IFLNK:
2297                 if (strbuf_readlink(buf, path, st->st_size) < 0)
2298                         return error(_("unable to read symlink %s"), path);
2299                 return 0;
2300         case S_IFREG:
2301                 if (strbuf_read_file(buf, path, st->st_size) != st->st_size)
2302                         return error(_("unable to open or read %s"), path);
2303                 /*
2304                  * "git apply" without "--index/--cached" should never look
2305                  * at the index; the target file may not have been added to
2306                  * the index yet, and we may not even be in any Git repository.
2307                  * Pass NULL to convert_to_git() to stress this; the function
2308                  * should never look at the index when explicit crlf option
2309                  * is given.
2310                  */
2311                 convert_to_git(NULL, path, buf->buf, buf->len, buf, safe_crlf);
2312                 return 0;
2313         default:
2314                 return -1;
2315         }
2316 }
2317
2318 /*
2319  * Update the preimage, and the common lines in postimage,
2320  * from buffer buf of length len. If postlen is 0 the postimage
2321  * is updated in place, otherwise it's updated on a new buffer
2322  * of length postlen
2323  */
2324
2325 static void update_pre_post_images(struct image *preimage,
2326                                    struct image *postimage,
2327                                    char *buf,
2328                                    size_t len, size_t postlen)
2329 {
2330         int i, ctx, reduced;
2331         char *new, *old, *fixed;
2332         struct image fixed_preimage;
2333
2334         /*
2335          * Update the preimage with whitespace fixes.  Note that we
2336          * are not losing preimage->buf -- apply_one_fragment() will
2337          * free "oldlines".
2338          */
2339         prepare_image(&fixed_preimage, buf, len, 1);
2340         assert(postlen
2341                ? fixed_preimage.nr == preimage->nr
2342                : fixed_preimage.nr <= preimage->nr);
2343         for (i = 0; i < fixed_preimage.nr; i++)
2344                 fixed_preimage.line[i].flag = preimage->line[i].flag;
2345         free(preimage->line_allocated);
2346         *preimage = fixed_preimage;
2347
2348         /*
2349          * Adjust the common context lines in postimage. This can be
2350          * done in-place when we are shrinking it with whitespace
2351          * fixing, but needs a new buffer when ignoring whitespace or
2352          * expanding leading tabs to spaces.
2353          *
2354          * We trust the caller to tell us if the update can be done
2355          * in place (postlen==0) or not.
2356          */
2357         old = postimage->buf;
2358         if (postlen)
2359                 new = postimage->buf = xmalloc(postlen);
2360         else
2361                 new = old;
2362         fixed = preimage->buf;
2363
2364         for (i = reduced = ctx = 0; i < postimage->nr; i++) {
2365                 size_t l_len = postimage->line[i].len;
2366                 if (!(postimage->line[i].flag & LINE_COMMON)) {
2367                         /* an added line -- no counterparts in preimage */
2368                         memmove(new, old, l_len);
2369                         old += l_len;
2370                         new += l_len;
2371                         continue;
2372                 }
2373
2374                 /* a common context -- skip it in the original postimage */
2375                 old += l_len;
2376
2377                 /* and find the corresponding one in the fixed preimage */
2378                 while (ctx < preimage->nr &&
2379                        !(preimage->line[ctx].flag & LINE_COMMON)) {
2380                         fixed += preimage->line[ctx].len;
2381                         ctx++;
2382                 }
2383
2384                 /*
2385                  * preimage is expected to run out, if the caller
2386                  * fixed addition of trailing blank lines.
2387                  */
2388                 if (preimage->nr <= ctx) {
2389                         reduced++;
2390                         continue;
2391                 }
2392
2393                 /* and copy it in, while fixing the line length */
2394                 l_len = preimage->line[ctx].len;
2395                 memcpy(new, fixed, l_len);
2396                 new += l_len;
2397                 fixed += l_len;
2398                 postimage->line[i].len = l_len;
2399                 ctx++;
2400         }
2401
2402         if (postlen
2403             ? postlen < new - postimage->buf
2404             : postimage->len < new - postimage->buf)
2405                 die("BUG: caller miscounted postlen: asked %d, orig = %d, used = %d",
2406                     (int)postlen, (int) postimage->len, (int)(new - postimage->buf));
2407
2408         /* Fix the length of the whole thing */
2409         postimage->len = new - postimage->buf;
2410         postimage->nr -= reduced;
2411 }
2412
2413 static int line_by_line_fuzzy_match(struct image *img,
2414                                     struct image *preimage,
2415                                     struct image *postimage,
2416                                     unsigned long try,
2417                                     int try_lno,
2418                                     int preimage_limit)
2419 {
2420         int i;
2421         size_t imgoff = 0;
2422         size_t preoff = 0;
2423         size_t postlen = postimage->len;
2424         size_t extra_chars;
2425         char *buf;
2426         char *preimage_eof;
2427         char *preimage_end;
2428         struct strbuf fixed;
2429         char *fixed_buf;
2430         size_t fixed_len;
2431
2432         for (i = 0; i < preimage_limit; i++) {
2433                 size_t prelen = preimage->line[i].len;
2434                 size_t imglen = img->line[try_lno+i].len;
2435
2436                 if (!fuzzy_matchlines(img->buf + try + imgoff, imglen,
2437                                       preimage->buf + preoff, prelen))
2438                         return 0;
2439                 if (preimage->line[i].flag & LINE_COMMON)
2440                         postlen += imglen - prelen;
2441                 imgoff += imglen;
2442                 preoff += prelen;
2443         }
2444
2445         /*
2446          * Ok, the preimage matches with whitespace fuzz.
2447          *
2448          * imgoff now holds the true length of the target that
2449          * matches the preimage before the end of the file.
2450          *
2451          * Count the number of characters in the preimage that fall
2452          * beyond the end of the file and make sure that all of them
2453          * are whitespace characters. (This can only happen if
2454          * we are removing blank lines at the end of the file.)
2455          */
2456         buf = preimage_eof = preimage->buf + preoff;
2457         for ( ; i < preimage->nr; i++)
2458                 preoff += preimage->line[i].len;
2459         preimage_end = preimage->buf + preoff;
2460         for ( ; buf < preimage_end; buf++)
2461                 if (!isspace(*buf))
2462                         return 0;
2463
2464         /*
2465          * Update the preimage and the common postimage context
2466          * lines to use the same whitespace as the target.
2467          * If whitespace is missing in the target (i.e.
2468          * if the preimage extends beyond the end of the file),
2469          * use the whitespace from the preimage.
2470          */
2471         extra_chars = preimage_end - preimage_eof;
2472         strbuf_init(&fixed, imgoff + extra_chars);
2473         strbuf_add(&fixed, img->buf + try, imgoff);
2474         strbuf_add(&fixed, preimage_eof, extra_chars);
2475         fixed_buf = strbuf_detach(&fixed, &fixed_len);
2476         update_pre_post_images(preimage, postimage,
2477                                fixed_buf, fixed_len, postlen);
2478         return 1;
2479 }
2480
2481 static int match_fragment(struct apply_state *state,
2482                           struct image *img,
2483                           struct image *preimage,
2484                           struct image *postimage,
2485                           unsigned long try,
2486                           int try_lno,
2487                           unsigned ws_rule,
2488                           int match_beginning, int match_end)
2489 {
2490         int i;
2491         char *fixed_buf, *buf, *orig, *target;
2492         struct strbuf fixed;
2493         size_t fixed_len, postlen;
2494         int preimage_limit;
2495
2496         if (preimage->nr + try_lno <= img->nr) {
2497                 /*
2498                  * The hunk falls within the boundaries of img.
2499                  */
2500                 preimage_limit = preimage->nr;
2501                 if (match_end && (preimage->nr + try_lno != img->nr))
2502                         return 0;
2503         } else if (state->ws_error_action == correct_ws_error &&
2504                    (ws_rule & WS_BLANK_AT_EOF)) {
2505                 /*
2506                  * This hunk extends beyond the end of img, and we are
2507                  * removing blank lines at the end of the file.  This
2508                  * many lines from the beginning of the preimage must
2509                  * match with img, and the remainder of the preimage
2510                  * must be blank.
2511                  */
2512                 preimage_limit = img->nr - try_lno;
2513         } else {
2514                 /*
2515                  * The hunk extends beyond the end of the img and
2516                  * we are not removing blanks at the end, so we
2517                  * should reject the hunk at this position.
2518                  */
2519                 return 0;
2520         }
2521
2522         if (match_beginning && try_lno)
2523                 return 0;
2524
2525         /* Quick hash check */
2526         for (i = 0; i < preimage_limit; i++)
2527                 if ((img->line[try_lno + i].flag & LINE_PATCHED) ||
2528                     (preimage->line[i].hash != img->line[try_lno + i].hash))
2529                         return 0;
2530
2531         if (preimage_limit == preimage->nr) {
2532                 /*
2533                  * Do we have an exact match?  If we were told to match
2534                  * at the end, size must be exactly at try+fragsize,
2535                  * otherwise try+fragsize must be still within the preimage,
2536                  * and either case, the old piece should match the preimage
2537                  * exactly.
2538                  */
2539                 if ((match_end
2540                      ? (try + preimage->len == img->len)
2541                      : (try + preimage->len <= img->len)) &&
2542                     !memcmp(img->buf + try, preimage->buf, preimage->len))
2543                         return 1;
2544         } else {
2545                 /*
2546                  * The preimage extends beyond the end of img, so
2547                  * there cannot be an exact match.
2548                  *
2549                  * There must be one non-blank context line that match
2550                  * a line before the end of img.
2551                  */
2552                 char *buf_end;
2553
2554                 buf = preimage->buf;
2555                 buf_end = buf;
2556                 for (i = 0; i < preimage_limit; i++)
2557                         buf_end += preimage->line[i].len;
2558
2559                 for ( ; buf < buf_end; buf++)
2560                         if (!isspace(*buf))
2561                                 break;
2562                 if (buf == buf_end)
2563                         return 0;
2564         }
2565
2566         /*
2567          * No exact match. If we are ignoring whitespace, run a line-by-line
2568          * fuzzy matching. We collect all the line length information because
2569          * we need it to adjust whitespace if we match.
2570          */
2571         if (state->ws_ignore_action == ignore_ws_change)
2572                 return line_by_line_fuzzy_match(img, preimage, postimage,
2573                                                 try, try_lno, preimage_limit);
2574
2575         if (state->ws_error_action != correct_ws_error)
2576                 return 0;
2577
2578         /*
2579          * The hunk does not apply byte-by-byte, but the hash says
2580          * it might with whitespace fuzz. We weren't asked to
2581          * ignore whitespace, we were asked to correct whitespace
2582          * errors, so let's try matching after whitespace correction.
2583          *
2584          * While checking the preimage against the target, whitespace
2585          * errors in both fixed, we count how large the corresponding
2586          * postimage needs to be.  The postimage prepared by
2587          * apply_one_fragment() has whitespace errors fixed on added
2588          * lines already, but the common lines were propagated as-is,
2589          * which may become longer when their whitespace errors are
2590          * fixed.
2591          */
2592
2593         /* First count added lines in postimage */
2594         postlen = 0;
2595         for (i = 0; i < postimage->nr; i++) {
2596                 if (!(postimage->line[i].flag & LINE_COMMON))
2597                         postlen += postimage->line[i].len;
2598         }
2599
2600         /*
2601          * The preimage may extend beyond the end of the file,
2602          * but in this loop we will only handle the part of the
2603          * preimage that falls within the file.
2604          */
2605         strbuf_init(&fixed, preimage->len + 1);
2606         orig = preimage->buf;
2607         target = img->buf + try;
2608         for (i = 0; i < preimage_limit; i++) {
2609                 size_t oldlen = preimage->line[i].len;
2610                 size_t tgtlen = img->line[try_lno + i].len;
2611                 size_t fixstart = fixed.len;
2612                 struct strbuf tgtfix;
2613                 int match;
2614
2615                 /* Try fixing the line in the preimage */
2616                 ws_fix_copy(&fixed, orig, oldlen, ws_rule, NULL);
2617
2618                 /* Try fixing the line in the target */
2619                 strbuf_init(&tgtfix, tgtlen);
2620                 ws_fix_copy(&tgtfix, target, tgtlen, ws_rule, NULL);
2621
2622                 /*
2623                  * If they match, either the preimage was based on
2624                  * a version before our tree fixed whitespace breakage,
2625                  * or we are lacking a whitespace-fix patch the tree
2626                  * the preimage was based on already had (i.e. target
2627                  * has whitespace breakage, the preimage doesn't).
2628                  * In either case, we are fixing the whitespace breakages
2629                  * so we might as well take the fix together with their
2630                  * real change.
2631                  */
2632                 match = (tgtfix.len == fixed.len - fixstart &&
2633                          !memcmp(tgtfix.buf, fixed.buf + fixstart,
2634                                              fixed.len - fixstart));
2635
2636                 /* Add the length if this is common with the postimage */
2637                 if (preimage->line[i].flag & LINE_COMMON)
2638                         postlen += tgtfix.len;
2639
2640                 strbuf_release(&tgtfix);
2641                 if (!match)
2642                         goto unmatch_exit;
2643
2644                 orig += oldlen;
2645                 target += tgtlen;
2646         }
2647
2648
2649         /*
2650          * Now handle the lines in the preimage that falls beyond the
2651          * end of the file (if any). They will only match if they are
2652          * empty or only contain whitespace (if WS_BLANK_AT_EOL is
2653          * false).
2654          */
2655         for ( ; i < preimage->nr; i++) {
2656                 size_t fixstart = fixed.len; /* start of the fixed preimage */
2657                 size_t oldlen = preimage->line[i].len;
2658                 int j;
2659
2660                 /* Try fixing the line in the preimage */
2661                 ws_fix_copy(&fixed, orig, oldlen, ws_rule, NULL);
2662
2663                 for (j = fixstart; j < fixed.len; j++)
2664                         if (!isspace(fixed.buf[j]))
2665                                 goto unmatch_exit;
2666
2667                 orig += oldlen;
2668         }
2669
2670         /*
2671          * Yes, the preimage is based on an older version that still
2672          * has whitespace breakages unfixed, and fixing them makes the
2673          * hunk match.  Update the context lines in the postimage.
2674          */
2675         fixed_buf = strbuf_detach(&fixed, &fixed_len);
2676         if (postlen < postimage->len)
2677                 postlen = 0;
2678         update_pre_post_images(preimage, postimage,
2679                                fixed_buf, fixed_len, postlen);
2680         return 1;
2681
2682  unmatch_exit:
2683         strbuf_release(&fixed);
2684         return 0;
2685 }
2686
2687 static int find_pos(struct apply_state *state,
2688                     struct image *img,
2689                     struct image *preimage,
2690                     struct image *postimage,
2691                     int line,
2692                     unsigned ws_rule,
2693                     int match_beginning, int match_end)
2694 {
2695         int i;
2696         unsigned long backwards, forwards, try;
2697         int backwards_lno, forwards_lno, try_lno;
2698
2699         /*
2700          * If match_beginning or match_end is specified, there is no
2701          * point starting from a wrong line that will never match and
2702          * wander around and wait for a match at the specified end.
2703          */
2704         if (match_beginning)
2705                 line = 0;
2706         else if (match_end)
2707                 line = img->nr - preimage->nr;
2708
2709         /*
2710          * Because the comparison is unsigned, the following test
2711          * will also take care of a negative line number that can
2712          * result when match_end and preimage is larger than the target.
2713          */
2714         if ((size_t) line > img->nr)
2715                 line = img->nr;
2716
2717         try = 0;
2718         for (i = 0; i < line; i++)
2719                 try += img->line[i].len;
2720
2721         /*
2722          * There's probably some smart way to do this, but I'll leave
2723          * that to the smart and beautiful people. I'm simple and stupid.
2724          */
2725         backwards = try;
2726         backwards_lno = line;
2727         forwards = try;
2728         forwards_lno = line;
2729         try_lno = line;
2730
2731         for (i = 0; ; i++) {
2732                 if (match_fragment(state, img, preimage, postimage,
2733                                    try, try_lno, ws_rule,
2734                                    match_beginning, match_end))
2735                         return try_lno;
2736
2737         again:
2738                 if (backwards_lno == 0 && forwards_lno == img->nr)
2739                         break;
2740
2741                 if (i & 1) {
2742                         if (backwards_lno == 0) {
2743                                 i++;
2744                                 goto again;
2745                         }
2746                         backwards_lno--;
2747                         backwards -= img->line[backwards_lno].len;
2748                         try = backwards;
2749                         try_lno = backwards_lno;
2750                 } else {
2751                         if (forwards_lno == img->nr) {
2752                                 i++;
2753                                 goto again;
2754                         }
2755                         forwards += img->line[forwards_lno].len;
2756                         forwards_lno++;
2757                         try = forwards;
2758                         try_lno = forwards_lno;
2759                 }
2760
2761         }
2762         return -1;
2763 }
2764
2765 static void remove_first_line(struct image *img)
2766 {
2767         img->buf += img->line[0].len;
2768         img->len -= img->line[0].len;
2769         img->line++;
2770         img->nr--;
2771 }
2772
2773 static void remove_last_line(struct image *img)
2774 {
2775         img->len -= img->line[--img->nr].len;
2776 }
2777
2778 /*
2779  * The change from "preimage" and "postimage" has been found to
2780  * apply at applied_pos (counts in line numbers) in "img".
2781  * Update "img" to remove "preimage" and replace it with "postimage".
2782  */
2783 static void update_image(struct apply_state *state,
2784                          struct image *img,
2785                          int applied_pos,
2786                          struct image *preimage,
2787                          struct image *postimage)
2788 {
2789         /*
2790          * remove the copy of preimage at offset in img
2791          * and replace it with postimage
2792          */
2793         int i, nr;
2794         size_t remove_count, insert_count, applied_at = 0;
2795         char *result;
2796         int preimage_limit;
2797
2798         /*
2799          * If we are removing blank lines at the end of img,
2800          * the preimage may extend beyond the end.
2801          * If that is the case, we must be careful only to
2802          * remove the part of the preimage that falls within
2803          * the boundaries of img. Initialize preimage_limit
2804          * to the number of lines in the preimage that falls
2805          * within the boundaries.
2806          */
2807         preimage_limit = preimage->nr;
2808         if (preimage_limit > img->nr - applied_pos)
2809                 preimage_limit = img->nr - applied_pos;
2810
2811         for (i = 0; i < applied_pos; i++)
2812                 applied_at += img->line[i].len;
2813
2814         remove_count = 0;
2815         for (i = 0; i < preimage_limit; i++)
2816                 remove_count += img->line[applied_pos + i].len;
2817         insert_count = postimage->len;
2818
2819         /* Adjust the contents */
2820         result = xmalloc(st_add3(st_sub(img->len, remove_count), insert_count, 1));
2821         memcpy(result, img->buf, applied_at);
2822         memcpy(result + applied_at, postimage->buf, postimage->len);
2823         memcpy(result + applied_at + postimage->len,
2824                img->buf + (applied_at + remove_count),
2825                img->len - (applied_at + remove_count));
2826         free(img->buf);
2827         img->buf = result;
2828         img->len += insert_count - remove_count;
2829         result[img->len] = '\0';
2830
2831         /* Adjust the line table */
2832         nr = img->nr + postimage->nr - preimage_limit;
2833         if (preimage_limit < postimage->nr) {
2834                 /*
2835                  * NOTE: this knows that we never call remove_first_line()
2836                  * on anything other than pre/post image.
2837                  */
2838                 REALLOC_ARRAY(img->line, nr);
2839                 img->line_allocated = img->line;
2840         }
2841         if (preimage_limit != postimage->nr)
2842                 MOVE_ARRAY(img->line + applied_pos + postimage->nr,
2843                            img->line + applied_pos + preimage_limit,
2844                            img->nr - (applied_pos + preimage_limit));
2845         COPY_ARRAY(img->line + applied_pos, postimage->line, postimage->nr);
2846         if (!state->allow_overlap)
2847                 for (i = 0; i < postimage->nr; i++)
2848                         img->line[applied_pos + i].flag |= LINE_PATCHED;
2849         img->nr = nr;
2850 }
2851
2852 /*
2853  * Use the patch-hunk text in "frag" to prepare two images (preimage and
2854  * postimage) for the hunk.  Find lines that match "preimage" in "img" and
2855  * replace the part of "img" with "postimage" text.
2856  */
2857 static int apply_one_fragment(struct apply_state *state,
2858                               struct image *img, struct fragment *frag,
2859                               int inaccurate_eof, unsigned ws_rule,
2860                               int nth_fragment)
2861 {
2862         int match_beginning, match_end;
2863         const char *patch = frag->patch;
2864         int size = frag->size;
2865         char *old, *oldlines;
2866         struct strbuf newlines;
2867         int new_blank_lines_at_end = 0;
2868         int found_new_blank_lines_at_end = 0;
2869         int hunk_linenr = frag->linenr;
2870         unsigned long leading, trailing;
2871         int pos, applied_pos;
2872         struct image preimage;
2873         struct image postimage;
2874
2875         memset(&preimage, 0, sizeof(preimage));
2876         memset(&postimage, 0, sizeof(postimage));
2877         oldlines = xmalloc(size);
2878         strbuf_init(&newlines, size);
2879
2880         old = oldlines;
2881         while (size > 0) {
2882                 char first;
2883                 int len = linelen(patch, size);
2884                 int plen;
2885                 int added_blank_line = 0;
2886                 int is_blank_context = 0;
2887                 size_t start;
2888
2889                 if (!len)
2890                         break;
2891
2892                 /*
2893                  * "plen" is how much of the line we should use for
2894                  * the actual patch data. Normally we just remove the
2895                  * first character on the line, but if the line is
2896                  * followed by "\ No newline", then we also remove the
2897                  * last one (which is the newline, of course).
2898                  */
2899                 plen = len - 1;
2900                 if (len < size && patch[len] == '\\')
2901                         plen--;
2902                 first = *patch;
2903                 if (state->apply_in_reverse) {
2904                         if (first == '-')
2905                                 first = '+';
2906                         else if (first == '+')
2907                                 first = '-';
2908                 }
2909
2910                 switch (first) {
2911                 case '\n':
2912                         /* Newer GNU diff, empty context line */
2913                         if (plen < 0)
2914                                 /* ... followed by '\No newline'; nothing */
2915                                 break;
2916                         *old++ = '\n';
2917                         strbuf_addch(&newlines, '\n');
2918                         add_line_info(&preimage, "\n", 1, LINE_COMMON);
2919                         add_line_info(&postimage, "\n", 1, LINE_COMMON);
2920                         is_blank_context = 1;
2921                         break;
2922                 case ' ':
2923                         if (plen && (ws_rule & WS_BLANK_AT_EOF) &&
2924                             ws_blank_line(patch + 1, plen, ws_rule))
2925                                 is_blank_context = 1;
2926                 case '-':
2927                         memcpy(old, patch + 1, plen);
2928                         add_line_info(&preimage, old, plen,
2929                                       (first == ' ' ? LINE_COMMON : 0));
2930                         old += plen;
2931                         if (first == '-')
2932                                 break;
2933                 /* Fall-through for ' ' */
2934                 case '+':
2935                         /* --no-add does not add new lines */
2936                         if (first == '+' && state->no_add)
2937                                 break;
2938
2939                         start = newlines.len;
2940                         if (first != '+' ||
2941                             !state->whitespace_error ||
2942                             state->ws_error_action != correct_ws_error) {
2943                                 strbuf_add(&newlines, patch + 1, plen);
2944                         }
2945                         else {
2946                                 ws_fix_copy(&newlines, patch + 1, plen, ws_rule, &state->applied_after_fixing_ws);
2947                         }
2948                         add_line_info(&postimage, newlines.buf + start, newlines.len - start,
2949                                       (first == '+' ? 0 : LINE_COMMON));
2950                         if (first == '+' &&
2951                             (ws_rule & WS_BLANK_AT_EOF) &&
2952                             ws_blank_line(patch + 1, plen, ws_rule))
2953                                 added_blank_line = 1;
2954                         break;
2955                 case '@': case '\\':
2956                         /* Ignore it, we already handled it */
2957                         break;
2958                 default:
2959                         if (state->apply_verbosity > verbosity_normal)
2960                                 error(_("invalid start of line: '%c'"), first);
2961                         applied_pos = -1;
2962                         goto out;
2963                 }
2964                 if (added_blank_line) {
2965                         if (!new_blank_lines_at_end)
2966                                 found_new_blank_lines_at_end = hunk_linenr;
2967                         new_blank_lines_at_end++;
2968                 }
2969                 else if (is_blank_context)
2970                         ;
2971                 else
2972                         new_blank_lines_at_end = 0;
2973                 patch += len;
2974                 size -= len;
2975                 hunk_linenr++;
2976         }
2977         if (inaccurate_eof &&
2978             old > oldlines && old[-1] == '\n' &&
2979             newlines.len > 0 && newlines.buf[newlines.len - 1] == '\n') {
2980                 old--;
2981                 strbuf_setlen(&newlines, newlines.len - 1);
2982         }
2983
2984         leading = frag->leading;
2985         trailing = frag->trailing;
2986
2987         /*
2988          * A hunk to change lines at the beginning would begin with
2989          * @@ -1,L +N,M @@
2990          * but we need to be careful.  -U0 that inserts before the second
2991          * line also has this pattern.
2992          *
2993          * And a hunk to add to an empty file would begin with
2994          * @@ -0,0 +N,M @@
2995          *
2996          * In other words, a hunk that is (frag->oldpos <= 1) with or
2997          * without leading context must match at the beginning.
2998          */
2999         match_beginning = (!frag->oldpos ||
3000                            (frag->oldpos == 1 && !state->unidiff_zero));
3001
3002         /*
3003          * A hunk without trailing lines must match at the end.
3004          * However, we simply cannot tell if a hunk must match end
3005          * from the lack of trailing lines if the patch was generated
3006          * with unidiff without any context.
3007          */
3008         match_end = !state->unidiff_zero && !trailing;
3009
3010         pos = frag->newpos ? (frag->newpos - 1) : 0;
3011         preimage.buf = oldlines;
3012         preimage.len = old - oldlines;
3013         postimage.buf = newlines.buf;
3014         postimage.len = newlines.len;
3015         preimage.line = preimage.line_allocated;
3016         postimage.line = postimage.line_allocated;
3017
3018         for (;;) {
3019
3020                 applied_pos = find_pos(state, img, &preimage, &postimage, pos,
3021                                        ws_rule, match_beginning, match_end);
3022
3023                 if (applied_pos >= 0)
3024                         break;
3025
3026                 /* Am I at my context limits? */
3027                 if ((leading <= state->p_context) && (trailing <= state->p_context))
3028                         break;
3029                 if (match_beginning || match_end) {
3030                         match_beginning = match_end = 0;
3031                         continue;
3032                 }
3033
3034                 /*
3035                  * Reduce the number of context lines; reduce both
3036                  * leading and trailing if they are equal otherwise
3037                  * just reduce the larger context.
3038                  */
3039                 if (leading >= trailing) {
3040                         remove_first_line(&preimage);
3041                         remove_first_line(&postimage);
3042                         pos--;
3043                         leading--;
3044                 }
3045                 if (trailing > leading) {
3046                         remove_last_line(&preimage);
3047                         remove_last_line(&postimage);
3048                         trailing--;
3049                 }
3050         }
3051
3052         if (applied_pos >= 0) {
3053                 if (new_blank_lines_at_end &&
3054                     preimage.nr + applied_pos >= img->nr &&
3055                     (ws_rule & WS_BLANK_AT_EOF) &&
3056                     state->ws_error_action != nowarn_ws_error) {
3057                         record_ws_error(state, WS_BLANK_AT_EOF, "+", 1,
3058                                         found_new_blank_lines_at_end);
3059                         if (state->ws_error_action == correct_ws_error) {
3060                                 while (new_blank_lines_at_end--)
3061                                         remove_last_line(&postimage);
3062                         }
3063                         /*
3064                          * We would want to prevent write_out_results()
3065                          * from taking place in apply_patch() that follows
3066                          * the callchain led us here, which is:
3067                          * apply_patch->check_patch_list->check_patch->
3068                          * apply_data->apply_fragments->apply_one_fragment
3069                          */
3070                         if (state->ws_error_action == die_on_ws_error)
3071                                 state->apply = 0;
3072                 }
3073
3074                 if (state->apply_verbosity > verbosity_normal && applied_pos != pos) {
3075                         int offset = applied_pos - pos;
3076                         if (state->apply_in_reverse)
3077                                 offset = 0 - offset;
3078                         fprintf_ln(stderr,
3079                                    Q_("Hunk #%d succeeded at %d (offset %d line).",
3080                                       "Hunk #%d succeeded at %d (offset %d lines).",
3081                                       offset),
3082                                    nth_fragment, applied_pos + 1, offset);
3083                 }
3084
3085                 /*
3086                  * Warn if it was necessary to reduce the number
3087                  * of context lines.
3088                  */
3089                 if ((leading != frag->leading ||
3090                      trailing != frag->trailing) && state->apply_verbosity > verbosity_silent)
3091                         fprintf_ln(stderr, _("Context reduced to (%ld/%ld)"
3092                                              " to apply fragment at %d"),
3093                                    leading, trailing, applied_pos+1);
3094                 update_image(state, img, applied_pos, &preimage, &postimage);
3095         } else {
3096                 if (state->apply_verbosity > verbosity_normal)
3097                         error(_("while searching for:\n%.*s"),
3098                               (int)(old - oldlines), oldlines);
3099         }
3100
3101 out:
3102         free(oldlines);
3103         strbuf_release(&newlines);
3104         free(preimage.line_allocated);
3105         free(postimage.line_allocated);
3106
3107         return (applied_pos < 0);
3108 }
3109
3110 static int apply_binary_fragment(struct apply_state *state,
3111                                  struct image *img,
3112                                  struct patch *patch)
3113 {
3114         struct fragment *fragment = patch->fragments;
3115         unsigned long len;
3116         void *dst;
3117
3118         if (!fragment)
3119                 return error(_("missing binary patch data for '%s'"),
3120                              patch->new_name ?
3121                              patch->new_name :
3122                              patch->old_name);
3123
3124         /* Binary patch is irreversible without the optional second hunk */
3125         if (state->apply_in_reverse) {
3126                 if (!fragment->next)
3127                         return error(_("cannot reverse-apply a binary patch "
3128                                        "without the reverse hunk to '%s'"),
3129                                      patch->new_name
3130                                      ? patch->new_name : patch->old_name);
3131                 fragment = fragment->next;
3132         }
3133         switch (fragment->binary_patch_method) {
3134         case BINARY_DELTA_DEFLATED:
3135                 dst = patch_delta(img->buf, img->len, fragment->patch,
3136                                   fragment->size, &len);
3137                 if (!dst)
3138                         return -1;
3139                 clear_image(img);
3140                 img->buf = dst;
3141                 img->len = len;
3142                 return 0;
3143         case BINARY_LITERAL_DEFLATED:
3144                 clear_image(img);
3145                 img->len = fragment->size;
3146                 img->buf = xmemdupz(fragment->patch, img->len);
3147                 return 0;
3148         }
3149         return -1;
3150 }
3151
3152 /*
3153  * Replace "img" with the result of applying the binary patch.
3154  * The binary patch data itself in patch->fragment is still kept
3155  * but the preimage prepared by the caller in "img" is freed here
3156  * or in the helper function apply_binary_fragment() this calls.
3157  */
3158 static int apply_binary(struct apply_state *state,
3159                         struct image *img,
3160                         struct patch *patch)
3161 {
3162         const char *name = patch->old_name ? patch->old_name : patch->new_name;
3163         struct object_id oid;
3164
3165         /*
3166          * For safety, we require patch index line to contain
3167          * full 40-byte textual SHA1 for old and new, at least for now.
3168          */
3169         if (strlen(patch->old_sha1_prefix) != 40 ||
3170             strlen(patch->new_sha1_prefix) != 40 ||
3171             get_oid_hex(patch->old_sha1_prefix, &oid) ||
3172             get_oid_hex(patch->new_sha1_prefix, &oid))
3173                 return error(_("cannot apply binary patch to '%s' "
3174                                "without full index line"), name);
3175
3176         if (patch->old_name) {
3177                 /*
3178                  * See if the old one matches what the patch
3179                  * applies to.
3180                  */
3181                 hash_sha1_file(img->buf, img->len, blob_type, oid.hash);
3182                 if (strcmp(oid_to_hex(&oid), patch->old_sha1_prefix))
3183                         return error(_("the patch applies to '%s' (%s), "
3184                                        "which does not match the "
3185                                        "current contents."),
3186                                      name, oid_to_hex(&oid));
3187         }
3188         else {
3189                 /* Otherwise, the old one must be empty. */
3190                 if (img->len)
3191                         return error(_("the patch applies to an empty "
3192                                        "'%s' but it is not empty"), name);
3193         }
3194
3195         get_oid_hex(patch->new_sha1_prefix, &oid);
3196         if (is_null_oid(&oid)) {
3197                 clear_image(img);
3198                 return 0; /* deletion patch */
3199         }
3200
3201         if (has_sha1_file(oid.hash)) {
3202                 /* We already have the postimage */
3203                 enum object_type type;
3204                 unsigned long size;
3205                 char *result;
3206
3207                 result = read_sha1_file(oid.hash, &type, &size);
3208                 if (!result)
3209                         return error(_("the necessary postimage %s for "
3210                                        "'%s' cannot be read"),
3211                                      patch->new_sha1_prefix, name);
3212                 clear_image(img);
3213                 img->buf = result;
3214                 img->len = size;
3215         } else {
3216                 /*
3217                  * We have verified buf matches the preimage;
3218                  * apply the patch data to it, which is stored
3219                  * in the patch->fragments->{patch,size}.
3220                  */
3221                 if (apply_binary_fragment(state, img, patch))
3222                         return error(_("binary patch does not apply to '%s'"),
3223                                      name);
3224
3225                 /* verify that the result matches */
3226                 hash_sha1_file(img->buf, img->len, blob_type, oid.hash);
3227                 if (strcmp(oid_to_hex(&oid), patch->new_sha1_prefix))
3228                         return error(_("binary patch to '%s' creates incorrect result (expecting %s, got %s)"),
3229                                 name, patch->new_sha1_prefix, oid_to_hex(&oid));
3230         }
3231
3232         return 0;
3233 }
3234
3235 static int apply_fragments(struct apply_state *state, struct image *img, struct patch *patch)
3236 {
3237         struct fragment *frag = patch->fragments;
3238         const char *name = patch->old_name ? patch->old_name : patch->new_name;
3239         unsigned ws_rule = patch->ws_rule;
3240         unsigned inaccurate_eof = patch->inaccurate_eof;
3241         int nth = 0;
3242
3243         if (patch->is_binary)
3244                 return apply_binary(state, img, patch);
3245
3246         while (frag) {
3247                 nth++;
3248                 if (apply_one_fragment(state, img, frag, inaccurate_eof, ws_rule, nth)) {
3249                         error(_("patch failed: %s:%ld"), name, frag->oldpos);
3250                         if (!state->apply_with_reject)
3251                                 return -1;
3252                         frag->rejected = 1;
3253                 }
3254                 frag = frag->next;
3255         }
3256         return 0;
3257 }
3258
3259 static int read_blob_object(struct strbuf *buf, const struct object_id *oid, unsigned mode)
3260 {
3261         if (S_ISGITLINK(mode)) {
3262                 strbuf_grow(buf, 100);
3263                 strbuf_addf(buf, "Subproject commit %s\n", oid_to_hex(oid));
3264         } else {
3265                 enum object_type type;
3266                 unsigned long sz;
3267                 char *result;
3268
3269                 result = read_sha1_file(oid->hash, &type, &sz);
3270                 if (!result)
3271                         return -1;
3272                 /* XXX read_sha1_file NUL-terminates */
3273                 strbuf_attach(buf, result, sz, sz + 1);
3274         }
3275         return 0;
3276 }
3277
3278 static int read_file_or_gitlink(const struct cache_entry *ce, struct strbuf *buf)
3279 {
3280         if (!ce)
3281                 return 0;
3282         return read_blob_object(buf, &ce->oid, ce->ce_mode);
3283 }
3284
3285 static struct patch *in_fn_table(struct apply_state *state, const char *name)
3286 {
3287         struct string_list_item *item;
3288
3289         if (name == NULL)
3290                 return NULL;
3291
3292         item = string_list_lookup(&state->fn_table, name);
3293         if (item != NULL)
3294                 return (struct patch *)item->util;
3295
3296         return NULL;
3297 }
3298
3299 /*
3300  * item->util in the filename table records the status of the path.
3301  * Usually it points at a patch (whose result records the contents
3302  * of it after applying it), but it could be PATH_WAS_DELETED for a
3303  * path that a previously applied patch has already removed, or
3304  * PATH_TO_BE_DELETED for a path that a later patch would remove.
3305  *
3306  * The latter is needed to deal with a case where two paths A and B
3307  * are swapped by first renaming A to B and then renaming B to A;
3308  * moving A to B should not be prevented due to presence of B as we
3309  * will remove it in a later patch.
3310  */
3311 #define PATH_TO_BE_DELETED ((struct patch *) -2)
3312 #define PATH_WAS_DELETED ((struct patch *) -1)
3313
3314 static int to_be_deleted(struct patch *patch)
3315 {
3316         return patch == PATH_TO_BE_DELETED;
3317 }
3318
3319 static int was_deleted(struct patch *patch)
3320 {
3321         return patch == PATH_WAS_DELETED;
3322 }
3323
3324 static void add_to_fn_table(struct apply_state *state, struct patch *patch)
3325 {
3326         struct string_list_item *item;
3327
3328         /*
3329          * Always add new_name unless patch is a deletion
3330          * This should cover the cases for normal diffs,
3331          * file creations and copies
3332          */
3333         if (patch->new_name != NULL) {
3334                 item = string_list_insert(&state->fn_table, patch->new_name);
3335                 item->util = patch;
3336         }
3337
3338         /*
3339          * store a failure on rename/deletion cases because
3340          * later chunks shouldn't patch old names
3341          */
3342         if ((patch->new_name == NULL) || (patch->is_rename)) {
3343                 item = string_list_insert(&state->fn_table, patch->old_name);
3344                 item->util = PATH_WAS_DELETED;
3345         }
3346 }
3347
3348 static void prepare_fn_table(struct apply_state *state, struct patch *patch)
3349 {
3350         /*
3351          * store information about incoming file deletion
3352          */
3353         while (patch) {
3354                 if ((patch->new_name == NULL) || (patch->is_rename)) {
3355                         struct string_list_item *item;
3356                         item = string_list_insert(&state->fn_table, patch->old_name);
3357                         item->util = PATH_TO_BE_DELETED;
3358                 }
3359                 patch = patch->next;
3360         }
3361 }
3362
3363 static int checkout_target(struct index_state *istate,
3364                            struct cache_entry *ce, struct stat *st)
3365 {
3366         struct checkout costate = CHECKOUT_INIT;
3367
3368         costate.refresh_cache = 1;
3369         costate.istate = istate;
3370         if (checkout_entry(ce, &costate, NULL) || lstat(ce->name, st))
3371                 return error(_("cannot checkout %s"), ce->name);
3372         return 0;
3373 }
3374
3375 static struct patch *previous_patch(struct apply_state *state,
3376                                     struct patch *patch,
3377                                     int *gone)
3378 {
3379         struct patch *previous;
3380
3381         *gone = 0;
3382         if (patch->is_copy || patch->is_rename)
3383                 return NULL; /* "git" patches do not depend on the order */
3384
3385         previous = in_fn_table(state, patch->old_name);
3386         if (!previous)
3387                 return NULL;
3388
3389         if (to_be_deleted(previous))
3390                 return NULL; /* the deletion hasn't happened yet */
3391
3392         if (was_deleted(previous))
3393                 *gone = 1;
3394
3395         return previous;
3396 }
3397
3398 static int verify_index_match(const struct cache_entry *ce, struct stat *st)
3399 {
3400         if (S_ISGITLINK(ce->ce_mode)) {
3401                 if (!S_ISDIR(st->st_mode))
3402                         return -1;
3403                 return 0;
3404         }
3405         return ce_match_stat(ce, st, CE_MATCH_IGNORE_VALID|CE_MATCH_IGNORE_SKIP_WORKTREE);
3406 }
3407
3408 #define SUBMODULE_PATCH_WITHOUT_INDEX 1
3409
3410 static int load_patch_target(struct apply_state *state,
3411                              struct strbuf *buf,
3412                              const struct cache_entry *ce,
3413                              struct stat *st,
3414                              struct patch *patch,
3415                              const char *name,
3416                              unsigned expected_mode)
3417 {
3418         if (state->cached || state->check_index) {
3419                 if (read_file_or_gitlink(ce, buf))
3420                         return error(_("failed to read %s"), name);
3421         } else if (name) {
3422                 if (S_ISGITLINK(expected_mode)) {
3423                         if (ce)
3424                                 return read_file_or_gitlink(ce, buf);
3425                         else
3426                                 return SUBMODULE_PATCH_WITHOUT_INDEX;
3427                 } else if (has_symlink_leading_path(name, strlen(name))) {
3428                         return error(_("reading from '%s' beyond a symbolic link"), name);
3429                 } else {
3430                         if (read_old_data(st, patch, name, buf))
3431                                 return error(_("failed to read %s"), name);
3432                 }
3433         }
3434         return 0;
3435 }
3436
3437 /*
3438  * We are about to apply "patch"; populate the "image" with the
3439  * current version we have, from the working tree or from the index,
3440  * depending on the situation e.g. --cached/--index.  If we are
3441  * applying a non-git patch that incrementally updates the tree,
3442  * we read from the result of a previous diff.
3443  */
3444 static int load_preimage(struct apply_state *state,
3445                          struct image *image,
3446                          struct patch *patch, struct stat *st,
3447                          const struct cache_entry *ce)
3448 {
3449         struct strbuf buf = STRBUF_INIT;
3450         size_t len;
3451         char *img;
3452         struct patch *previous;
3453         int status;
3454
3455         previous = previous_patch(state, patch, &status);
3456         if (status)
3457                 return error(_("path %s has been renamed/deleted"),
3458                              patch->old_name);
3459         if (previous) {
3460                 /* We have a patched copy in memory; use that. */
3461                 strbuf_add(&buf, previous->result, previous->resultsize);
3462         } else {
3463                 status = load_patch_target(state, &buf, ce, st, patch,
3464                                            patch->old_name, patch->old_mode);
3465                 if (status < 0)
3466                         return status;
3467                 else if (status == SUBMODULE_PATCH_WITHOUT_INDEX) {
3468                         /*
3469                          * There is no way to apply subproject
3470                          * patch without looking at the index.
3471                          * NEEDSWORK: shouldn't this be flagged
3472                          * as an error???
3473                          */
3474                         free_fragment_list(patch->fragments);
3475                         patch->fragments = NULL;
3476                 } else if (status) {
3477                         return error(_("failed to read %s"), patch->old_name);
3478                 }
3479         }
3480
3481         img = strbuf_detach(&buf, &len);
3482         prepare_image(image, img, len, !patch->is_binary);
3483         return 0;
3484 }
3485
3486 static int three_way_merge(struct image *image,
3487                            char *path,
3488                            const struct object_id *base,
3489                            const struct object_id *ours,
3490                            const struct object_id *theirs)
3491 {
3492         mmfile_t base_file, our_file, their_file;
3493         mmbuffer_t result = { NULL };
3494         int status;
3495
3496         read_mmblob(&base_file, base);
3497         read_mmblob(&our_file, ours);
3498         read_mmblob(&their_file, theirs);
3499         status = ll_merge(&result, path,
3500                           &base_file, "base",
3501                           &our_file, "ours",
3502                           &their_file, "theirs", NULL);
3503         free(base_file.ptr);
3504         free(our_file.ptr);
3505         free(their_file.ptr);
3506         if (status < 0 || !result.ptr) {
3507                 free(result.ptr);
3508                 return -1;
3509         }
3510         clear_image(image);
3511         image->buf = result.ptr;
3512         image->len = result.size;
3513
3514         return status;
3515 }
3516
3517 /*
3518  * When directly falling back to add/add three-way merge, we read from
3519  * the current contents of the new_name.  In no cases other than that
3520  * this function will be called.
3521  */
3522 static int load_current(struct apply_state *state,
3523                         struct image *image,
3524                         struct patch *patch)
3525 {
3526         struct strbuf buf = STRBUF_INIT;
3527         int status, pos;
3528         size_t len;
3529         char *img;
3530         struct stat st;
3531         struct cache_entry *ce;
3532         char *name = patch->new_name;
3533         unsigned mode = patch->new_mode;
3534
3535         if (!patch->is_new)
3536                 die("BUG: patch to %s is not a creation", patch->old_name);
3537
3538         pos = cache_name_pos(name, strlen(name));
3539         if (pos < 0)
3540                 return error(_("%s: does not exist in index"), name);
3541         ce = active_cache[pos];
3542         if (lstat(name, &st)) {
3543                 if (errno != ENOENT)
3544                         return error_errno("%s", name);
3545                 if (checkout_target(&the_index, ce, &st))
3546                         return -1;
3547         }
3548         if (verify_index_match(ce, &st))
3549                 return error(_("%s: does not match index"), name);
3550
3551         status = load_patch_target(state, &buf, ce, &st, patch, name, mode);
3552         if (status < 0)
3553                 return status;
3554         else if (status)
3555                 return -1;
3556         img = strbuf_detach(&buf, &len);
3557         prepare_image(image, img, len, !patch->is_binary);
3558         return 0;
3559 }
3560
3561 static int try_threeway(struct apply_state *state,
3562                         struct image *image,
3563                         struct patch *patch,
3564                         struct stat *st,
3565                         const struct cache_entry *ce)
3566 {
3567         struct object_id pre_oid, post_oid, our_oid;
3568         struct strbuf buf = STRBUF_INIT;
3569         size_t len;
3570         int status;
3571         char *img;
3572         struct image tmp_image;
3573
3574         /* No point falling back to 3-way merge in these cases */
3575         if (patch->is_delete ||
3576             S_ISGITLINK(patch->old_mode) || S_ISGITLINK(patch->new_mode))
3577                 return -1;
3578
3579         /* Preimage the patch was prepared for */
3580         if (patch->is_new)
3581                 write_sha1_file("", 0, blob_type, pre_oid.hash);
3582         else if (get_sha1(patch->old_sha1_prefix, pre_oid.hash) ||
3583                  read_blob_object(&buf, &pre_oid, patch->old_mode))
3584                 return error(_("repository lacks the necessary blob to fall back on 3-way merge."));
3585
3586         if (state->apply_verbosity > verbosity_silent)
3587                 fprintf(stderr, _("Falling back to three-way merge...\n"));
3588
3589         img = strbuf_detach(&buf, &len);
3590         prepare_image(&tmp_image, img, len, 1);
3591         /* Apply the patch to get the post image */
3592         if (apply_fragments(state, &tmp_image, patch) < 0) {
3593                 clear_image(&tmp_image);
3594                 return -1;
3595         }
3596         /* post_oid is theirs */
3597         write_sha1_file(tmp_image.buf, tmp_image.len, blob_type, post_oid.hash);
3598         clear_image(&tmp_image);
3599
3600         /* our_oid is ours */
3601         if (patch->is_new) {
3602                 if (load_current(state, &tmp_image, patch))
3603                         return error(_("cannot read the current contents of '%s'"),
3604                                      patch->new_name);
3605         } else {
3606                 if (load_preimage(state, &tmp_image, patch, st, ce))
3607                         return error(_("cannot read the current contents of '%s'"),
3608                                      patch->old_name);
3609         }
3610         write_sha1_file(tmp_image.buf, tmp_image.len, blob_type, our_oid.hash);
3611         clear_image(&tmp_image);
3612
3613         /* in-core three-way merge between post and our using pre as base */
3614         status = three_way_merge(image, patch->new_name,
3615                                  &pre_oid, &our_oid, &post_oid);
3616         if (status < 0) {
3617                 if (state->apply_verbosity > verbosity_silent)
3618                         fprintf(stderr,
3619                                 _("Failed to fall back on three-way merge...\n"));
3620                 return status;
3621         }
3622
3623         if (status) {
3624                 patch->conflicted_threeway = 1;
3625                 if (patch->is_new)
3626                         oidclr(&patch->threeway_stage[0]);
3627                 else
3628                         oidcpy(&patch->threeway_stage[0], &pre_oid);
3629                 oidcpy(&patch->threeway_stage[1], &our_oid);
3630                 oidcpy(&patch->threeway_stage[2], &post_oid);
3631                 if (state->apply_verbosity > verbosity_silent)
3632                         fprintf(stderr,
3633                                 _("Applied patch to '%s' with conflicts.\n"),
3634                                 patch->new_name);
3635         } else {
3636                 if (state->apply_verbosity > verbosity_silent)
3637                         fprintf(stderr,
3638                                 _("Applied patch to '%s' cleanly.\n"),
3639                                 patch->new_name);
3640         }
3641         return 0;
3642 }
3643
3644 static int apply_data(struct apply_state *state, struct patch *patch,
3645                       struct stat *st, const struct cache_entry *ce)
3646 {
3647         struct image image;
3648
3649         if (load_preimage(state, &image, patch, st, ce) < 0)
3650                 return -1;
3651
3652         if (patch->direct_to_threeway ||
3653             apply_fragments(state, &image, patch) < 0) {
3654                 /* Note: with --reject, apply_fragments() returns 0 */
3655                 if (!state->threeway || try_threeway(state, &image, patch, st, ce) < 0)
3656                         return -1;
3657         }
3658         patch->result = image.buf;
3659         patch->resultsize = image.len;
3660         add_to_fn_table(state, patch);
3661         free(image.line_allocated);
3662
3663         if (0 < patch->is_delete && patch->resultsize)
3664                 return error(_("removal patch leaves file contents"));
3665
3666         return 0;
3667 }
3668
3669 /*
3670  * If "patch" that we are looking at modifies or deletes what we have,
3671  * we would want it not to lose any local modification we have, either
3672  * in the working tree or in the index.
3673  *
3674  * This also decides if a non-git patch is a creation patch or a
3675  * modification to an existing empty file.  We do not check the state
3676  * of the current tree for a creation patch in this function; the caller
3677  * check_patch() separately makes sure (and errors out otherwise) that
3678  * the path the patch creates does not exist in the current tree.
3679  */
3680 static int check_preimage(struct apply_state *state,
3681                           struct patch *patch,
3682                           struct cache_entry **ce,
3683                           struct stat *st)
3684 {
3685         const char *old_name = patch->old_name;
3686         struct patch *previous = NULL;
3687         int stat_ret = 0, status;
3688         unsigned st_mode = 0;
3689
3690         if (!old_name)
3691                 return 0;
3692
3693         assert(patch->is_new <= 0);
3694         previous = previous_patch(state, patch, &status);
3695
3696         if (status)
3697                 return error(_("path %s has been renamed/deleted"), old_name);
3698         if (previous) {
3699                 st_mode = previous->new_mode;
3700         } else if (!state->cached) {
3701                 stat_ret = lstat(old_name, st);
3702                 if (stat_ret && errno != ENOENT)
3703                         return error_errno("%s", old_name);
3704         }
3705
3706         if (state->check_index && !previous) {
3707                 int pos = cache_name_pos(old_name, strlen(old_name));
3708                 if (pos < 0) {
3709                         if (patch->is_new < 0)
3710                                 goto is_new;
3711                         return error(_("%s: does not exist in index"), old_name);
3712                 }
3713                 *ce = active_cache[pos];
3714                 if (stat_ret < 0) {
3715                         if (checkout_target(&the_index, *ce, st))
3716                                 return -1;
3717                 }
3718                 if (!state->cached && verify_index_match(*ce, st))
3719                         return error(_("%s: does not match index"), old_name);
3720                 if (state->cached)
3721                         st_mode = (*ce)->ce_mode;
3722         } else if (stat_ret < 0) {
3723                 if (patch->is_new < 0)
3724                         goto is_new;
3725                 return error_errno("%s", old_name);
3726         }
3727
3728         if (!state->cached && !previous)
3729                 st_mode = ce_mode_from_stat(*ce, st->st_mode);
3730
3731         if (patch->is_new < 0)
3732                 patch->is_new = 0;
3733         if (!patch->old_mode)
3734                 patch->old_mode = st_mode;
3735         if ((st_mode ^ patch->old_mode) & S_IFMT)
3736                 return error(_("%s: wrong type"), old_name);
3737         if (st_mode != patch->old_mode)
3738                 warning(_("%s has type %o, expected %o"),
3739                         old_name, st_mode, patch->old_mode);
3740         if (!patch->new_mode && !patch->is_delete)
3741                 patch->new_mode = st_mode;
3742         return 0;
3743
3744  is_new:
3745         patch->is_new = 1;
3746         patch->is_delete = 0;
3747         FREE_AND_NULL(patch->old_name);
3748         return 0;
3749 }
3750
3751
3752 #define EXISTS_IN_INDEX 1
3753 #define EXISTS_IN_WORKTREE 2
3754
3755 static int check_to_create(struct apply_state *state,
3756                            const char *new_name,
3757                            int ok_if_exists)
3758 {
3759         struct stat nst;
3760
3761         if (state->check_index &&
3762             cache_name_pos(new_name, strlen(new_name)) >= 0 &&
3763             !ok_if_exists)
3764                 return EXISTS_IN_INDEX;
3765         if (state->cached)
3766                 return 0;
3767
3768         if (!lstat(new_name, &nst)) {
3769                 if (S_ISDIR(nst.st_mode) || ok_if_exists)
3770                         return 0;
3771                 /*
3772                  * A leading component of new_name might be a symlink
3773                  * that is going to be removed with this patch, but
3774                  * still pointing at somewhere that has the path.
3775                  * In such a case, path "new_name" does not exist as
3776                  * far as git is concerned.
3777                  */
3778                 if (has_symlink_leading_path(new_name, strlen(new_name)))
3779                         return 0;
3780
3781                 return EXISTS_IN_WORKTREE;
3782         } else if (!is_missing_file_error(errno)) {
3783                 return error_errno("%s", new_name);
3784         }
3785         return 0;
3786 }
3787
3788 static uintptr_t register_symlink_changes(struct apply_state *state,
3789                                           const char *path,
3790                                           uintptr_t what)
3791 {
3792         struct string_list_item *ent;
3793
3794         ent = string_list_lookup(&state->symlink_changes, path);
3795         if (!ent) {
3796                 ent = string_list_insert(&state->symlink_changes, path);
3797                 ent->util = (void *)0;
3798         }
3799         ent->util = (void *)(what | ((uintptr_t)ent->util));
3800         return (uintptr_t)ent->util;
3801 }
3802
3803 static uintptr_t check_symlink_changes(struct apply_state *state, const char *path)
3804 {
3805         struct string_list_item *ent;
3806
3807         ent = string_list_lookup(&state->symlink_changes, path);
3808         if (!ent)
3809                 return 0;
3810         return (uintptr_t)ent->util;
3811 }
3812
3813 static void prepare_symlink_changes(struct apply_state *state, struct patch *patch)
3814 {
3815         for ( ; patch; patch = patch->next) {
3816                 if ((patch->old_name && S_ISLNK(patch->old_mode)) &&
3817                     (patch->is_rename || patch->is_delete))
3818                         /* the symlink at patch->old_name is removed */
3819                         register_symlink_changes(state, patch->old_name, APPLY_SYMLINK_GOES_AWAY);
3820
3821                 if (patch->new_name && S_ISLNK(patch->new_mode))
3822                         /* the symlink at patch->new_name is created or remains */
3823                         register_symlink_changes(state, patch->new_name, APPLY_SYMLINK_IN_RESULT);
3824         }
3825 }
3826
3827 static int path_is_beyond_symlink_1(struct apply_state *state, struct strbuf *name)
3828 {
3829         do {
3830                 unsigned int change;
3831
3832                 while (--name->len && name->buf[name->len] != '/')
3833                         ; /* scan backwards */
3834                 if (!name->len)
3835                         break;
3836                 name->buf[name->len] = '\0';
3837                 change = check_symlink_changes(state, name->buf);
3838                 if (change & APPLY_SYMLINK_IN_RESULT)
3839                         return 1;
3840                 if (change & APPLY_SYMLINK_GOES_AWAY)
3841                         /*
3842                          * This cannot be "return 0", because we may
3843                          * see a new one created at a higher level.
3844                          */
3845                         continue;
3846
3847                 /* otherwise, check the preimage */
3848                 if (state->check_index) {
3849                         struct cache_entry *ce;
3850
3851                         ce = cache_file_exists(name->buf, name->len, ignore_case);
3852                         if (ce && S_ISLNK(ce->ce_mode))
3853                                 return 1;
3854                 } else {
3855                         struct stat st;
3856                         if (!lstat(name->buf, &st) && S_ISLNK(st.st_mode))
3857                                 return 1;
3858                 }
3859         } while (1);
3860         return 0;
3861 }
3862
3863 static int path_is_beyond_symlink(struct apply_state *state, const char *name_)
3864 {
3865         int ret;
3866         struct strbuf name = STRBUF_INIT;
3867
3868         assert(*name_ != '\0');
3869         strbuf_addstr(&name, name_);
3870         ret = path_is_beyond_symlink_1(state, &name);
3871         strbuf_release(&name);
3872
3873         return ret;
3874 }
3875
3876 static int check_unsafe_path(struct patch *patch)
3877 {
3878         const char *old_name = NULL;
3879         const char *new_name = NULL;
3880         if (patch->is_delete)
3881                 old_name = patch->old_name;
3882         else if (!patch->is_new && !patch->is_copy)
3883                 old_name = patch->old_name;
3884         if (!patch->is_delete)
3885                 new_name = patch->new_name;
3886
3887         if (old_name && !verify_path(old_name))
3888                 return error(_("invalid path '%s'"), old_name);
3889         if (new_name && !verify_path(new_name))
3890                 return error(_("invalid path '%s'"), new_name);
3891         return 0;
3892 }
3893
3894 /*
3895  * Check and apply the patch in-core; leave the result in patch->result
3896  * for the caller to write it out to the final destination.
3897  */
3898 static int check_patch(struct apply_state *state, struct patch *patch)
3899 {
3900         struct stat st;
3901         const char *old_name = patch->old_name;
3902         const char *new_name = patch->new_name;
3903         const char *name = old_name ? old_name : new_name;
3904         struct cache_entry *ce = NULL;
3905         struct patch *tpatch;
3906         int ok_if_exists;
3907         int status;
3908
3909         patch->rejected = 1; /* we will drop this after we succeed */
3910
3911         status = check_preimage(state, patch, &ce, &st);
3912         if (status)
3913                 return status;
3914         old_name = patch->old_name;
3915
3916         /*
3917          * A type-change diff is always split into a patch to delete
3918          * old, immediately followed by a patch to create new (see
3919          * diff.c::run_diff()); in such a case it is Ok that the entry
3920          * to be deleted by the previous patch is still in the working
3921          * tree and in the index.
3922          *
3923          * A patch to swap-rename between A and B would first rename A
3924          * to B and then rename B to A.  While applying the first one,
3925          * the presence of B should not stop A from getting renamed to
3926          * B; ask to_be_deleted() about the later rename.  Removal of
3927          * B and rename from A to B is handled the same way by asking
3928          * was_deleted().
3929          */
3930         if ((tpatch = in_fn_table(state, new_name)) &&
3931             (was_deleted(tpatch) || to_be_deleted(tpatch)))
3932                 ok_if_exists = 1;
3933         else
3934                 ok_if_exists = 0;
3935
3936         if (new_name &&
3937             ((0 < patch->is_new) || patch->is_rename || patch->is_copy)) {
3938                 int err = check_to_create(state, new_name, ok_if_exists);
3939
3940                 if (err && state->threeway) {
3941                         patch->direct_to_threeway = 1;
3942                 } else switch (err) {
3943                 case 0:
3944                         break; /* happy */
3945                 case EXISTS_IN_INDEX:
3946                         return error(_("%s: already exists in index"), new_name);
3947                         break;
3948                 case EXISTS_IN_WORKTREE:
3949                         return error(_("%s: already exists in working directory"),
3950                                      new_name);
3951                 default:
3952                         return err;
3953                 }
3954
3955                 if (!patch->new_mode) {
3956                         if (0 < patch->is_new)
3957                                 patch->new_mode = S_IFREG | 0644;
3958                         else
3959                                 patch->new_mode = patch->old_mode;
3960                 }
3961         }
3962
3963         if (new_name && old_name) {
3964                 int same = !strcmp(old_name, new_name);
3965                 if (!patch->new_mode)
3966                         patch->new_mode = patch->old_mode;
3967                 if ((patch->old_mode ^ patch->new_mode) & S_IFMT) {
3968                         if (same)
3969                                 return error(_("new mode (%o) of %s does not "
3970                                                "match old mode (%o)"),
3971                                         patch->new_mode, new_name,
3972                                         patch->old_mode);
3973                         else
3974                                 return error(_("new mode (%o) of %s does not "
3975                                                "match old mode (%o) of %s"),
3976                                         patch->new_mode, new_name,
3977                                         patch->old_mode, old_name);
3978                 }
3979         }
3980
3981         if (!state->unsafe_paths && check_unsafe_path(patch))
3982                 return -128;
3983
3984         /*
3985          * An attempt to read from or delete a path that is beyond a
3986          * symbolic link will be prevented by load_patch_target() that
3987          * is called at the beginning of apply_data() so we do not
3988          * have to worry about a patch marked with "is_delete" bit
3989          * here.  We however need to make sure that the patch result
3990          * is not deposited to a path that is beyond a symbolic link
3991          * here.
3992          */
3993         if (!patch->is_delete && path_is_beyond_symlink(state, patch->new_name))
3994                 return error(_("affected file '%s' is beyond a symbolic link"),
3995                              patch->new_name);
3996
3997         if (apply_data(state, patch, &st, ce) < 0)
3998                 return error(_("%s: patch does not apply"), name);
3999         patch->rejected = 0;
4000         return 0;
4001 }
4002
4003 static int check_patch_list(struct apply_state *state, struct patch *patch)
4004 {
4005         int err = 0;
4006
4007         prepare_symlink_changes(state, patch);
4008         prepare_fn_table(state, patch);
4009         while (patch) {
4010                 int res;
4011                 if (state->apply_verbosity > verbosity_normal)
4012                         say_patch_name(stderr,
4013                                        _("Checking patch %s..."), patch);
4014                 res = check_patch(state, patch);
4015                 if (res == -128)
4016                         return -128;
4017                 err |= res;
4018                 patch = patch->next;
4019         }
4020         return err;
4021 }
4022
4023 static int read_apply_cache(struct apply_state *state)
4024 {
4025         if (state->index_file)
4026                 return read_cache_from(state->index_file);
4027         else
4028                 return read_cache();
4029 }
4030
4031 /* This function tries to read the object name from the current index */
4032 static int get_current_oid(struct apply_state *state, const char *path,
4033                            struct object_id *oid)
4034 {
4035         int pos;
4036
4037         if (read_apply_cache(state) < 0)
4038                 return -1;
4039         pos = cache_name_pos(path, strlen(path));
4040         if (pos < 0)
4041                 return -1;
4042         oidcpy(oid, &active_cache[pos]->oid);
4043         return 0;
4044 }
4045
4046 static int preimage_oid_in_gitlink_patch(struct patch *p, struct object_id *oid)
4047 {
4048         /*
4049          * A usable gitlink patch has only one fragment (hunk) that looks like:
4050          * @@ -1 +1 @@
4051          * -Subproject commit <old sha1>
4052          * +Subproject commit <new sha1>
4053          * or
4054          * @@ -1 +0,0 @@
4055          * -Subproject commit <old sha1>
4056          * for a removal patch.
4057          */
4058         struct fragment *hunk = p->fragments;
4059         static const char heading[] = "-Subproject commit ";
4060         char *preimage;
4061
4062         if (/* does the patch have only one hunk? */
4063             hunk && !hunk->next &&
4064             /* is its preimage one line? */
4065             hunk->oldpos == 1 && hunk->oldlines == 1 &&
4066             /* does preimage begin with the heading? */
4067             (preimage = memchr(hunk->patch, '\n', hunk->size)) != NULL &&
4068             starts_with(++preimage, heading) &&
4069             /* does it record full SHA-1? */
4070             !get_oid_hex(preimage + sizeof(heading) - 1, oid) &&
4071             preimage[sizeof(heading) + GIT_SHA1_HEXSZ - 1] == '\n' &&
4072             /* does the abbreviated name on the index line agree with it? */
4073             starts_with(preimage + sizeof(heading) - 1, p->old_sha1_prefix))
4074                 return 0; /* it all looks fine */
4075
4076         /* we may have full object name on the index line */
4077         return get_oid_hex(p->old_sha1_prefix, oid);
4078 }
4079
4080 /* Build an index that contains the just the files needed for a 3way merge */
4081 static int build_fake_ancestor(struct apply_state *state, struct patch *list)
4082 {
4083         struct patch *patch;
4084         struct index_state result = { NULL };
4085         static struct lock_file lock;
4086         int res;
4087
4088         /* Once we start supporting the reverse patch, it may be
4089          * worth showing the new sha1 prefix, but until then...
4090          */
4091         for (patch = list; patch; patch = patch->next) {
4092                 struct object_id oid;
4093                 struct cache_entry *ce;
4094                 const char *name;
4095
4096                 name = patch->old_name ? patch->old_name : patch->new_name;
4097                 if (0 < patch->is_new)
4098                         continue;
4099
4100                 if (S_ISGITLINK(patch->old_mode)) {
4101                         if (!preimage_oid_in_gitlink_patch(patch, &oid))
4102                                 ; /* ok, the textual part looks sane */
4103                         else
4104                                 return error(_("sha1 information is lacking or "
4105                                                "useless for submodule %s"), name);
4106                 } else if (!get_sha1_blob(patch->old_sha1_prefix, oid.hash)) {
4107                         ; /* ok */
4108                 } else if (!patch->lines_added && !patch->lines_deleted) {
4109                         /* mode-only change: update the current */
4110                         if (get_current_oid(state, patch->old_name, &oid))
4111                                 return error(_("mode change for %s, which is not "
4112                                                "in current HEAD"), name);
4113                 } else
4114                         return error(_("sha1 information is lacking or useless "
4115                                        "(%s)."), name);
4116
4117                 ce = make_cache_entry(patch->old_mode, oid.hash, name, 0, 0);
4118                 if (!ce)
4119                         return error(_("make_cache_entry failed for path '%s'"),
4120                                      name);
4121                 if (add_index_entry(&result, ce, ADD_CACHE_OK_TO_ADD)) {
4122                         free(ce);
4123                         return error(_("could not add %s to temporary index"),
4124                                      name);
4125                 }
4126         }
4127
4128         hold_lock_file_for_update(&lock, state->fake_ancestor, LOCK_DIE_ON_ERROR);
4129         res = write_locked_index(&result, &lock, COMMIT_LOCK);
4130         discard_index(&result);
4131
4132         if (res)
4133                 return error(_("could not write temporary index to %s"),
4134                              state->fake_ancestor);
4135
4136         return 0;
4137 }
4138
4139 static void stat_patch_list(struct apply_state *state, struct patch *patch)
4140 {
4141         int files, adds, dels;
4142
4143         for (files = adds = dels = 0 ; patch ; patch = patch->next) {
4144                 files++;
4145                 adds += patch->lines_added;
4146                 dels += patch->lines_deleted;
4147                 show_stats(state, patch);
4148         }
4149
4150         print_stat_summary(stdout, files, adds, dels);
4151 }
4152
4153 static void numstat_patch_list(struct apply_state *state,
4154                                struct patch *patch)
4155 {
4156         for ( ; patch; patch = patch->next) {
4157                 const char *name;
4158                 name = patch->new_name ? patch->new_name : patch->old_name;
4159                 if (patch->is_binary)
4160                         printf("-\t-\t");
4161                 else
4162                         printf("%d\t%d\t", patch->lines_added, patch->lines_deleted);
4163                 write_name_quoted(name, stdout, state->line_termination);
4164         }
4165 }
4166
4167 static void show_file_mode_name(const char *newdelete, unsigned int mode, const char *name)
4168 {
4169         if (mode)
4170                 printf(" %s mode %06o %s\n", newdelete, mode, name);
4171         else
4172                 printf(" %s %s\n", newdelete, name);
4173 }
4174
4175 static void show_mode_change(struct patch *p, int show_name)
4176 {
4177         if (p->old_mode && p->new_mode && p->old_mode != p->new_mode) {
4178                 if (show_name)
4179                         printf(" mode change %06o => %06o %s\n",
4180                                p->old_mode, p->new_mode, p->new_name);
4181                 else
4182                         printf(" mode change %06o => %06o\n",
4183                                p->old_mode, p->new_mode);
4184         }
4185 }
4186
4187 static void show_rename_copy(struct patch *p)
4188 {
4189         const char *renamecopy = p->is_rename ? "rename" : "copy";
4190         const char *old, *new;
4191
4192         /* Find common prefix */
4193         old = p->old_name;
4194         new = p->new_name;
4195         while (1) {
4196                 const char *slash_old, *slash_new;
4197                 slash_old = strchr(old, '/');
4198                 slash_new = strchr(new, '/');
4199                 if (!slash_old ||
4200                     !slash_new ||
4201                     slash_old - old != slash_new - new ||
4202                     memcmp(old, new, slash_new - new))
4203                         break;
4204                 old = slash_old + 1;
4205                 new = slash_new + 1;
4206         }
4207         /* p->old_name thru old is the common prefix, and old and new
4208          * through the end of names are renames
4209          */
4210         if (old != p->old_name)
4211                 printf(" %s %.*s{%s => %s} (%d%%)\n", renamecopy,
4212                        (int)(old - p->old_name), p->old_name,
4213                        old, new, p->score);
4214         else
4215                 printf(" %s %s => %s (%d%%)\n", renamecopy,
4216                        p->old_name, p->new_name, p->score);
4217         show_mode_change(p, 0);
4218 }
4219
4220 static void summary_patch_list(struct patch *patch)
4221 {
4222         struct patch *p;
4223
4224         for (p = patch; p; p = p->next) {
4225                 if (p->is_new)
4226                         show_file_mode_name("create", p->new_mode, p->new_name);
4227                 else if (p->is_delete)
4228                         show_file_mode_name("delete", p->old_mode, p->old_name);
4229                 else {
4230                         if (p->is_rename || p->is_copy)
4231                                 show_rename_copy(p);
4232                         else {
4233                                 if (p->score) {
4234                                         printf(" rewrite %s (%d%%)\n",
4235                                                p->new_name, p->score);
4236                                         show_mode_change(p, 0);
4237                                 }
4238                                 else
4239                                         show_mode_change(p, 1);
4240                         }
4241                 }
4242         }
4243 }
4244
4245 static void patch_stats(struct apply_state *state, struct patch *patch)
4246 {
4247         int lines = patch->lines_added + patch->lines_deleted;
4248
4249         if (lines > state->max_change)
4250                 state->max_change = lines;
4251         if (patch->old_name) {
4252                 int len = quote_c_style(patch->old_name, NULL, NULL, 0);
4253                 if (!len)
4254                         len = strlen(patch->old_name);
4255                 if (len > state->max_len)
4256                         state->max_len = len;
4257         }
4258         if (patch->new_name) {
4259                 int len = quote_c_style(patch->new_name, NULL, NULL, 0);
4260                 if (!len)
4261                         len = strlen(patch->new_name);
4262                 if (len > state->max_len)
4263                         state->max_len = len;
4264         }
4265 }
4266
4267 static int remove_file(struct apply_state *state, struct patch *patch, int rmdir_empty)
4268 {
4269         if (state->update_index) {
4270                 if (remove_file_from_cache(patch->old_name) < 0)
4271                         return error(_("unable to remove %s from index"), patch->old_name);
4272         }
4273         if (!state->cached) {
4274                 if (!remove_or_warn(patch->old_mode, patch->old_name) && rmdir_empty) {
4275                         remove_path(patch->old_name);
4276                 }
4277         }
4278         return 0;
4279 }
4280
4281 static int add_index_file(struct apply_state *state,
4282                           const char *path,
4283                           unsigned mode,
4284                           void *buf,
4285                           unsigned long size)
4286 {
4287         struct stat st;
4288         struct cache_entry *ce;
4289         int namelen = strlen(path);
4290         unsigned ce_size = cache_entry_size(namelen);
4291
4292         if (!state->update_index)
4293                 return 0;
4294
4295         ce = xcalloc(1, ce_size);
4296         memcpy(ce->name, path, namelen);
4297         ce->ce_mode = create_ce_mode(mode);
4298         ce->ce_flags = create_ce_flags(0);
4299         ce->ce_namelen = namelen;
4300         if (S_ISGITLINK(mode)) {
4301                 const char *s;
4302
4303                 if (!skip_prefix(buf, "Subproject commit ", &s) ||
4304                     get_oid_hex(s, &ce->oid)) {
4305                         free(ce);
4306                        return error(_("corrupt patch for submodule %s"), path);
4307                 }
4308         } else {
4309                 if (!state->cached) {
4310                         if (lstat(path, &st) < 0) {
4311                                 free(ce);
4312                                 return error_errno(_("unable to stat newly "
4313                                                      "created file '%s'"),
4314                                                    path);
4315                         }
4316                         fill_stat_cache_info(ce, &st);
4317                 }
4318                 if (write_sha1_file(buf, size, blob_type, ce->oid.hash) < 0) {
4319                         free(ce);
4320                         return error(_("unable to create backing store "
4321                                        "for newly created file %s"), path);
4322                 }
4323         }
4324         if (add_cache_entry(ce, ADD_CACHE_OK_TO_ADD) < 0) {
4325                 free(ce);
4326                 return error(_("unable to add cache entry for %s"), path);
4327         }
4328
4329         return 0;
4330 }
4331
4332 /*
4333  * Returns:
4334  *  -1 if an unrecoverable error happened
4335  *   0 if everything went well
4336  *   1 if a recoverable error happened
4337  */
4338 static int try_create_file(const char *path, unsigned int mode, const char *buf, unsigned long size)
4339 {
4340         int fd, res;
4341         struct strbuf nbuf = STRBUF_INIT;
4342
4343         if (S_ISGITLINK(mode)) {
4344                 struct stat st;
4345                 if (!lstat(path, &st) && S_ISDIR(st.st_mode))
4346                         return 0;
4347                 return !!mkdir(path, 0777);
4348         }
4349
4350         if (has_symlinks && S_ISLNK(mode))
4351                 /* Although buf:size is counted string, it also is NUL
4352                  * terminated.
4353                  */
4354                 return !!symlink(buf, path);
4355
4356         fd = open(path, O_CREAT | O_EXCL | O_WRONLY, (mode & 0100) ? 0777 : 0666);
4357         if (fd < 0)
4358                 return 1;
4359
4360         if (convert_to_working_tree(path, buf, size, &nbuf)) {
4361                 size = nbuf.len;
4362                 buf  = nbuf.buf;
4363         }
4364
4365         res = write_in_full(fd, buf, size) < 0;
4366         if (res)
4367                 error_errno(_("failed to write to '%s'"), path);
4368         strbuf_release(&nbuf);
4369
4370         if (close(fd) < 0 && !res)
4371                 return error_errno(_("closing file '%s'"), path);
4372
4373         return res ? -1 : 0;
4374 }
4375
4376 /*
4377  * We optimistically assume that the directories exist,
4378  * which is true 99% of the time anyway. If they don't,
4379  * we create them and try again.
4380  *
4381  * Returns:
4382  *   -1 on error
4383  *   0 otherwise
4384  */
4385 static int create_one_file(struct apply_state *state,
4386                            char *path,
4387                            unsigned mode,
4388                            const char *buf,
4389                            unsigned long size)
4390 {
4391         int res;
4392
4393         if (state->cached)
4394                 return 0;
4395
4396         res = try_create_file(path, mode, buf, size);
4397         if (res < 0)
4398                 return -1;
4399         if (!res)
4400                 return 0;
4401
4402         if (errno == ENOENT) {
4403                 if (safe_create_leading_directories(path))
4404                         return 0;
4405                 res = try_create_file(path, mode, buf, size);
4406                 if (res < 0)
4407                         return -1;
4408                 if (!res)
4409                         return 0;
4410         }
4411
4412         if (errno == EEXIST || errno == EACCES) {
4413                 /* We may be trying to create a file where a directory
4414                  * used to be.
4415                  */
4416                 struct stat st;
4417                 if (!lstat(path, &st) && (!S_ISDIR(st.st_mode) || !rmdir(path)))
4418                         errno = EEXIST;
4419         }
4420
4421         if (errno == EEXIST) {
4422                 unsigned int nr = getpid();
4423
4424                 for (;;) {
4425                         char newpath[PATH_MAX];
4426                         mksnpath(newpath, sizeof(newpath), "%s~%u", path, nr);
4427                         res = try_create_file(newpath, mode, buf, size);
4428                         if (res < 0)
4429                                 return -1;
4430                         if (!res) {
4431                                 if (!rename(newpath, path))
4432                                         return 0;
4433                                 unlink_or_warn(newpath);
4434                                 break;
4435                         }
4436                         if (errno != EEXIST)
4437                                 break;
4438                         ++nr;
4439                 }
4440         }
4441         return error_errno(_("unable to write file '%s' mode %o"),
4442                            path, mode);
4443 }
4444
4445 static int add_conflicted_stages_file(struct apply_state *state,
4446                                        struct patch *patch)
4447 {
4448         int stage, namelen;
4449         unsigned ce_size, mode;
4450         struct cache_entry *ce;
4451
4452         if (!state->update_index)
4453                 return 0;
4454         namelen = strlen(patch->new_name);
4455         ce_size = cache_entry_size(namelen);
4456         mode = patch->new_mode ? patch->new_mode : (S_IFREG | 0644);
4457
4458         remove_file_from_cache(patch->new_name);
4459         for (stage = 1; stage < 4; stage++) {
4460                 if (is_null_oid(&patch->threeway_stage[stage - 1]))
4461                         continue;
4462                 ce = xcalloc(1, ce_size);
4463                 memcpy(ce->name, patch->new_name, namelen);
4464                 ce->ce_mode = create_ce_mode(mode);
4465                 ce->ce_flags = create_ce_flags(stage);
4466                 ce->ce_namelen = namelen;
4467                 oidcpy(&ce->oid, &patch->threeway_stage[stage - 1]);
4468                 if (add_cache_entry(ce, ADD_CACHE_OK_TO_ADD) < 0) {
4469                         free(ce);
4470                         return error(_("unable to add cache entry for %s"),
4471                                      patch->new_name);
4472                 }
4473         }
4474
4475         return 0;
4476 }
4477
4478 static int create_file(struct apply_state *state, struct patch *patch)
4479 {
4480         char *path = patch->new_name;
4481         unsigned mode = patch->new_mode;
4482         unsigned long size = patch->resultsize;
4483         char *buf = patch->result;
4484
4485         if (!mode)
4486                 mode = S_IFREG | 0644;
4487         if (create_one_file(state, path, mode, buf, size))
4488                 return -1;
4489
4490         if (patch->conflicted_threeway)
4491                 return add_conflicted_stages_file(state, patch);
4492         else
4493                 return add_index_file(state, path, mode, buf, size);
4494 }
4495
4496 /* phase zero is to remove, phase one is to create */
4497 static int write_out_one_result(struct apply_state *state,
4498                                 struct patch *patch,
4499                                 int phase)
4500 {
4501         if (patch->is_delete > 0) {
4502                 if (phase == 0)
4503                         return remove_file(state, patch, 1);
4504                 return 0;
4505         }
4506         if (patch->is_new > 0 || patch->is_copy) {
4507                 if (phase == 1)
4508                         return create_file(state, patch);
4509                 return 0;
4510         }
4511         /*
4512          * Rename or modification boils down to the same
4513          * thing: remove the old, write the new
4514          */
4515         if (phase == 0)
4516                 return remove_file(state, patch, patch->is_rename);
4517         if (phase == 1)
4518                 return create_file(state, patch);
4519         return 0;
4520 }
4521
4522 static int write_out_one_reject(struct apply_state *state, struct patch *patch)
4523 {
4524         FILE *rej;
4525         char namebuf[PATH_MAX];
4526         struct fragment *frag;
4527         int cnt = 0;
4528         struct strbuf sb = STRBUF_INIT;
4529
4530         for (cnt = 0, frag = patch->fragments; frag; frag = frag->next) {
4531                 if (!frag->rejected)
4532                         continue;
4533                 cnt++;
4534         }
4535
4536         if (!cnt) {
4537                 if (state->apply_verbosity > verbosity_normal)
4538                         say_patch_name(stderr,
4539                                        _("Applied patch %s cleanly."), patch);
4540                 return 0;
4541         }
4542
4543         /* This should not happen, because a removal patch that leaves
4544          * contents are marked "rejected" at the patch level.
4545          */
4546         if (!patch->new_name)
4547                 die(_("internal error"));
4548
4549         /* Say this even without --verbose */
4550         strbuf_addf(&sb, Q_("Applying patch %%s with %d reject...",
4551                             "Applying patch %%s with %d rejects...",
4552                             cnt),
4553                     cnt);
4554         if (state->apply_verbosity > verbosity_silent)
4555                 say_patch_name(stderr, sb.buf, patch);
4556         strbuf_release(&sb);
4557
4558         cnt = strlen(patch->new_name);
4559         if (ARRAY_SIZE(namebuf) <= cnt + 5) {
4560                 cnt = ARRAY_SIZE(namebuf) - 5;
4561                 warning(_("truncating .rej filename to %.*s.rej"),
4562                         cnt - 1, patch->new_name);
4563         }
4564         memcpy(namebuf, patch->new_name, cnt);
4565         memcpy(namebuf + cnt, ".rej", 5);
4566
4567         rej = fopen(namebuf, "w");
4568         if (!rej)
4569                 return error_errno(_("cannot open %s"), namebuf);
4570
4571         /* Normal git tools never deal with .rej, so do not pretend
4572          * this is a git patch by saying --git or giving extended
4573          * headers.  While at it, maybe please "kompare" that wants
4574          * the trailing TAB and some garbage at the end of line ;-).
4575          */
4576         fprintf(rej, "diff a/%s b/%s\t(rejected hunks)\n",
4577                 patch->new_name, patch->new_name);
4578         for (cnt = 1, frag = patch->fragments;
4579              frag;
4580              cnt++, frag = frag->next) {
4581                 if (!frag->rejected) {
4582                         if (state->apply_verbosity > verbosity_silent)
4583                                 fprintf_ln(stderr, _("Hunk #%d applied cleanly."), cnt);
4584                         continue;
4585                 }
4586                 if (state->apply_verbosity > verbosity_silent)
4587                         fprintf_ln(stderr, _("Rejected hunk #%d."), cnt);
4588                 fprintf(rej, "%.*s", frag->size, frag->patch);
4589                 if (frag->patch[frag->size-1] != '\n')
4590                         fputc('\n', rej);
4591         }
4592         fclose(rej);
4593         return -1;
4594 }
4595
4596 /*
4597  * Returns:
4598  *  -1 if an error happened
4599  *   0 if the patch applied cleanly
4600  *   1 if the patch did not apply cleanly
4601  */
4602 static int write_out_results(struct apply_state *state, struct patch *list)
4603 {
4604         int phase;
4605         int errs = 0;
4606         struct patch *l;
4607         struct string_list cpath = STRING_LIST_INIT_DUP;
4608
4609         for (phase = 0; phase < 2; phase++) {
4610                 l = list;
4611                 while (l) {
4612                         if (l->rejected)
4613                                 errs = 1;
4614                         else {
4615                                 if (write_out_one_result(state, l, phase)) {
4616                                         string_list_clear(&cpath, 0);
4617                                         return -1;
4618                                 }
4619                                 if (phase == 1) {
4620                                         if (write_out_one_reject(state, l))
4621                                                 errs = 1;
4622                                         if (l->conflicted_threeway) {
4623                                                 string_list_append(&cpath, l->new_name);
4624                                                 errs = 1;
4625                                         }
4626                                 }
4627                         }
4628                         l = l->next;
4629                 }
4630         }
4631
4632         if (cpath.nr) {
4633                 struct string_list_item *item;
4634
4635                 string_list_sort(&cpath);
4636                 if (state->apply_verbosity > verbosity_silent) {
4637                         for_each_string_list_item(item, &cpath)
4638                                 fprintf(stderr, "U %s\n", item->string);
4639                 }
4640                 string_list_clear(&cpath, 0);
4641
4642                 rerere(0);
4643         }
4644
4645         return errs;
4646 }
4647
4648 /*
4649  * Try to apply a patch.
4650  *
4651  * Returns:
4652  *  -128 if a bad error happened (like patch unreadable)
4653  *  -1 if patch did not apply and user cannot deal with it
4654  *   0 if the patch applied
4655  *   1 if the patch did not apply but user might fix it
4656  */
4657 static int apply_patch(struct apply_state *state,
4658                        int fd,
4659                        const char *filename,
4660                        int options)
4661 {
4662         size_t offset;
4663         struct strbuf buf = STRBUF_INIT; /* owns the patch text */
4664         struct patch *list = NULL, **listp = &list;
4665         int skipped_patch = 0;
4666         int res = 0;
4667
4668         state->patch_input_file = filename;
4669         if (read_patch_file(&buf, fd) < 0)
4670                 return -128;
4671         offset = 0;
4672         while (offset < buf.len) {
4673                 struct patch *patch;
4674                 int nr;
4675
4676                 patch = xcalloc(1, sizeof(*patch));
4677                 patch->inaccurate_eof = !!(options & APPLY_OPT_INACCURATE_EOF);
4678                 patch->recount =  !!(options & APPLY_OPT_RECOUNT);
4679                 nr = parse_chunk(state, buf.buf + offset, buf.len - offset, patch);
4680                 if (nr < 0) {
4681                         free_patch(patch);
4682                         if (nr == -128) {
4683                                 res = -128;
4684                                 goto end;
4685                         }
4686                         break;
4687                 }
4688                 if (state->apply_in_reverse)
4689                         reverse_patches(patch);
4690                 if (use_patch(state, patch)) {
4691                         patch_stats(state, patch);
4692                         *listp = patch;
4693                         listp = &patch->next;
4694                 }
4695                 else {
4696                         if (state->apply_verbosity > verbosity_normal)
4697                                 say_patch_name(stderr, _("Skipped patch '%s'."), patch);
4698                         free_patch(patch);
4699                         skipped_patch++;
4700                 }
4701                 offset += nr;
4702         }
4703
4704         if (!list && !skipped_patch) {
4705                 error(_("unrecognized input"));
4706                 res = -128;
4707                 goto end;
4708         }
4709
4710         if (state->whitespace_error && (state->ws_error_action == die_on_ws_error))
4711                 state->apply = 0;
4712
4713         state->update_index = state->check_index && state->apply;
4714         if (state->update_index && state->newfd < 0) {
4715                 if (state->index_file)
4716                         state->newfd = hold_lock_file_for_update(state->lock_file,
4717                                                                  state->index_file,
4718                                                                  LOCK_DIE_ON_ERROR);
4719                 else
4720                         state->newfd = hold_locked_index(state->lock_file, LOCK_DIE_ON_ERROR);
4721         }
4722
4723         if (state->check_index && read_apply_cache(state) < 0) {
4724                 error(_("unable to read index file"));
4725                 res = -128;
4726                 goto end;
4727         }
4728
4729         if (state->check || state->apply) {
4730                 int r = check_patch_list(state, list);
4731                 if (r == -128) {
4732                         res = -128;
4733                         goto end;
4734                 }
4735                 if (r < 0 && !state->apply_with_reject) {
4736                         res = -1;
4737                         goto end;
4738                 }
4739         }
4740
4741         if (state->apply) {
4742                 int write_res = write_out_results(state, list);
4743                 if (write_res < 0) {
4744                         res = -128;
4745                         goto end;
4746                 }
4747                 if (write_res > 0) {
4748                         /* with --3way, we still need to write the index out */
4749                         res = state->apply_with_reject ? -1 : 1;
4750                         goto end;
4751                 }
4752         }
4753
4754         if (state->fake_ancestor &&
4755             build_fake_ancestor(state, list)) {
4756                 res = -128;
4757                 goto end;
4758         }
4759
4760         if (state->diffstat && state->apply_verbosity > verbosity_silent)
4761                 stat_patch_list(state, list);
4762
4763         if (state->numstat && state->apply_verbosity > verbosity_silent)
4764                 numstat_patch_list(state, list);
4765
4766         if (state->summary && state->apply_verbosity > verbosity_silent)
4767                 summary_patch_list(list);
4768
4769 end:
4770         free_patch_list(list);
4771         strbuf_release(&buf);
4772         string_list_clear(&state->fn_table, 0);
4773         return res;
4774 }
4775
4776 static int apply_option_parse_exclude(const struct option *opt,
4777                                       const char *arg, int unset)
4778 {
4779         struct apply_state *state = opt->value;
4780         add_name_limit(state, arg, 1);
4781         return 0;
4782 }
4783
4784 static int apply_option_parse_include(const struct option *opt,
4785                                       const char *arg, int unset)
4786 {
4787         struct apply_state *state = opt->value;
4788         add_name_limit(state, arg, 0);
4789         state->has_include = 1;
4790         return 0;
4791 }
4792
4793 static int apply_option_parse_p(const struct option *opt,
4794                                 const char *arg,
4795                                 int unset)
4796 {
4797         struct apply_state *state = opt->value;
4798         state->p_value = atoi(arg);
4799         state->p_value_known = 1;
4800         return 0;
4801 }
4802
4803 static int apply_option_parse_space_change(const struct option *opt,
4804                                            const char *arg, int unset)
4805 {
4806         struct apply_state *state = opt->value;
4807         if (unset)
4808                 state->ws_ignore_action = ignore_ws_none;
4809         else
4810                 state->ws_ignore_action = ignore_ws_change;
4811         return 0;
4812 }
4813
4814 static int apply_option_parse_whitespace(const struct option *opt,
4815                                          const char *arg, int unset)
4816 {
4817         struct apply_state *state = opt->value;
4818         state->whitespace_option = arg;
4819         if (parse_whitespace_option(state, arg))
4820                 exit(1);
4821         return 0;
4822 }
4823
4824 static int apply_option_parse_directory(const struct option *opt,
4825                                         const char *arg, int unset)
4826 {
4827         struct apply_state *state = opt->value;
4828         strbuf_reset(&state->root);
4829         strbuf_addstr(&state->root, arg);
4830         strbuf_complete(&state->root, '/');
4831         return 0;
4832 }
4833
4834 int apply_all_patches(struct apply_state *state,
4835                       int argc,
4836                       const char **argv,
4837                       int options)
4838 {
4839         int i;
4840         int res;
4841         int errs = 0;
4842         int read_stdin = 1;
4843
4844         for (i = 0; i < argc; i++) {
4845                 const char *arg = argv[i];
4846                 char *to_free = NULL;
4847                 int fd;
4848
4849                 if (!strcmp(arg, "-")) {
4850                         res = apply_patch(state, 0, "<stdin>", options);
4851                         if (res < 0)
4852                                 goto end;
4853                         errs |= res;
4854                         read_stdin = 0;
4855                         continue;
4856                 } else
4857                         arg = to_free = prefix_filename(state->prefix, arg);
4858
4859                 fd = open(arg, O_RDONLY);
4860                 if (fd < 0) {
4861                         error(_("can't open patch '%s': %s"), arg, strerror(errno));
4862                         res = -128;
4863                         free(to_free);
4864                         goto end;
4865                 }
4866                 read_stdin = 0;
4867                 set_default_whitespace_mode(state);
4868                 res = apply_patch(state, fd, arg, options);
4869                 close(fd);
4870                 free(to_free);
4871                 if (res < 0)
4872                         goto end;
4873                 errs |= res;
4874         }
4875         set_default_whitespace_mode(state);
4876         if (read_stdin) {
4877                 res = apply_patch(state, 0, "<stdin>", options);
4878                 if (res < 0)
4879                         goto end;
4880                 errs |= res;
4881         }
4882
4883         if (state->whitespace_error) {
4884                 if (state->squelch_whitespace_errors &&
4885                     state->squelch_whitespace_errors < state->whitespace_error) {
4886                         int squelched =
4887                                 state->whitespace_error - state->squelch_whitespace_errors;
4888                         warning(Q_("squelched %d whitespace error",
4889                                    "squelched %d whitespace errors",
4890                                    squelched),
4891                                 squelched);
4892                 }
4893                 if (state->ws_error_action == die_on_ws_error) {
4894                         error(Q_("%d line adds whitespace errors.",
4895                                  "%d lines add whitespace errors.",
4896                                  state->whitespace_error),
4897                               state->whitespace_error);
4898                         res = -128;
4899                         goto end;
4900                 }
4901                 if (state->applied_after_fixing_ws && state->apply)
4902                         warning(Q_("%d line applied after"
4903                                    " fixing whitespace errors.",
4904                                    "%d lines applied after"
4905                                    " fixing whitespace errors.",
4906                                    state->applied_after_fixing_ws),
4907                                 state->applied_after_fixing_ws);
4908                 else if (state->whitespace_error)
4909                         warning(Q_("%d line adds whitespace errors.",
4910                                    "%d lines add whitespace errors.",
4911                                    state->whitespace_error),
4912                                 state->whitespace_error);
4913         }
4914
4915         if (state->update_index) {
4916                 res = write_locked_index(&the_index, state->lock_file, COMMIT_LOCK);
4917                 if (res) {
4918                         error(_("Unable to write new index file"));
4919                         res = -128;
4920                         goto end;
4921                 }
4922                 state->newfd = -1;
4923         }
4924
4925         res = !!errs;
4926
4927 end:
4928         if (state->newfd >= 0) {
4929                 rollback_lock_file(state->lock_file);
4930                 state->newfd = -1;
4931         }
4932
4933         if (state->apply_verbosity <= verbosity_silent) {
4934                 set_error_routine(state->saved_error_routine);
4935                 set_warn_routine(state->saved_warn_routine);
4936         }
4937
4938         if (res > -1)
4939                 return res;
4940         return (res == -1 ? 1 : 128);
4941 }
4942
4943 int apply_parse_options(int argc, const char **argv,
4944                         struct apply_state *state,
4945                         int *force_apply, int *options,
4946                         const char * const *apply_usage)
4947 {
4948         struct option builtin_apply_options[] = {
4949                 { OPTION_CALLBACK, 0, "exclude", state, N_("path"),
4950                         N_("don't apply changes matching the given path"),
4951                         0, apply_option_parse_exclude },
4952                 { OPTION_CALLBACK, 0, "include", state, N_("path"),
4953                         N_("apply changes matching the given path"),
4954                         0, apply_option_parse_include },
4955                 { OPTION_CALLBACK, 'p', NULL, state, N_("num"),
4956                         N_("remove <num> leading slashes from traditional diff paths"),
4957                         0, apply_option_parse_p },
4958                 OPT_BOOL(0, "no-add", &state->no_add,
4959                         N_("ignore additions made by the patch")),
4960                 OPT_BOOL(0, "stat", &state->diffstat,
4961                         N_("instead of applying the patch, output diffstat for the input")),
4962                 OPT_NOOP_NOARG(0, "allow-binary-replacement"),
4963                 OPT_NOOP_NOARG(0, "binary"),
4964                 OPT_BOOL(0, "numstat", &state->numstat,
4965                         N_("show number of added and deleted lines in decimal notation")),
4966                 OPT_BOOL(0, "summary", &state->summary,
4967                         N_("instead of applying the patch, output a summary for the input")),
4968                 OPT_BOOL(0, "check", &state->check,
4969                         N_("instead of applying the patch, see if the patch is applicable")),
4970                 OPT_BOOL(0, "index", &state->check_index,
4971                         N_("make sure the patch is applicable to the current index")),
4972                 OPT_BOOL(0, "cached", &state->cached,
4973                         N_("apply a patch without touching the working tree")),
4974                 OPT_BOOL(0, "unsafe-paths", &state->unsafe_paths,
4975                         N_("accept a patch that touches outside the working area")),
4976                 OPT_BOOL(0, "apply", force_apply,
4977                         N_("also apply the patch (use with --stat/--summary/--check)")),
4978                 OPT_BOOL('3', "3way", &state->threeway,
4979                          N_( "attempt three-way merge if a patch does not apply")),
4980                 OPT_FILENAME(0, "build-fake-ancestor", &state->fake_ancestor,
4981                         N_("build a temporary index based on embedded index information")),
4982                 /* Think twice before adding "--nul" synonym to this */
4983                 OPT_SET_INT('z', NULL, &state->line_termination,
4984                         N_("paths are separated with NUL character"), '\0'),
4985                 OPT_INTEGER('C', NULL, &state->p_context,
4986                                 N_("ensure at least <n> lines of context match")),
4987                 { OPTION_CALLBACK, 0, "whitespace", state, N_("action"),
4988                         N_("detect new or modified lines that have whitespace errors"),
4989                         0, apply_option_parse_whitespace },
4990                 { OPTION_CALLBACK, 0, "ignore-space-change", state, NULL,
4991                         N_("ignore changes in whitespace when finding context"),
4992                         PARSE_OPT_NOARG, apply_option_parse_space_change },
4993                 { OPTION_CALLBACK, 0, "ignore-whitespace", state, NULL,
4994                         N_("ignore changes in whitespace when finding context"),
4995                         PARSE_OPT_NOARG, apply_option_parse_space_change },
4996                 OPT_BOOL('R', "reverse", &state->apply_in_reverse,
4997                         N_("apply the patch in reverse")),
4998                 OPT_BOOL(0, "unidiff-zero", &state->unidiff_zero,
4999                         N_("don't expect at least one line of context")),
5000                 OPT_BOOL(0, "reject", &state->apply_with_reject,
5001                         N_("leave the rejected hunks in corresponding *.rej files")),
5002                 OPT_BOOL(0, "allow-overlap", &state->allow_overlap,
5003                         N_("allow overlapping hunks")),
5004                 OPT__VERBOSE(&state->apply_verbosity, N_("be verbose")),
5005                 OPT_BIT(0, "inaccurate-eof", options,
5006                         N_("tolerate incorrectly detected missing new-line at the end of file"),
5007                         APPLY_OPT_INACCURATE_EOF),
5008                 OPT_BIT(0, "recount", options,
5009                         N_("do not trust the line counts in the hunk headers"),
5010                         APPLY_OPT_RECOUNT),
5011                 { OPTION_CALLBACK, 0, "directory", state, N_("root"),
5012                         N_("prepend <root> to all filenames"),
5013                         0, apply_option_parse_directory },
5014                 OPT_END()
5015         };
5016
5017         return parse_options(argc, argv, state->prefix, builtin_apply_options, apply_usage, 0);
5018 }