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