flthdr.c

   1 /****************************************************************************/
   2 /*
   3  *      A simple program to manipulate flat files
   4  *
   5  *      Copyright (C) 2001-2003 SnapGear Inc, davidm@snapgear.com
   6  *      Copyright (C) 2001 Lineo, davidm@lineo.com
   7  *
   8  * This is Free Software, under the GNU Public Licence v2 or greater.
   9  *
  10  */
  11 /****************************************************************************/
  12
  13 #include <stdio.h>    /* Userland pieces of the ANSI C standard I/O package  */
  14 #include <unistd.h>   /* Userland prototypes of the Unix std system calls    */
  15 #include <time.h>
  16 #include <stdlib.h>   /* exit() */
  17 #include <string.h>   /* strcat(), strcpy() */
  18
  19 /* macros for conversion between host and (internet) network byte order */
  20 #ifndef WIN32
  21 #include <netinet/in.h> /* Consts and structs defined by the internet system */
  22 #else
  23 #include <winsock2.h>
  24 #endif
  25
  26 /* from uClinux-x.x.x/include/linux */
  27 #include "flat.h"     /* Binary flat header description                      */
  28
  29 #if defined(__MINGW32__)
  30 #include <getopt.h>
  31
  32 #define mkstemp(p) mktemp(p)
  33
  34 #endif
  35
  36 /****************************************************************************/
  37
  38 char *program_name;
  39
  40 static char cmd[1024];
  41 static int print = 0, compress = 0, ramload = 0, stacksize = 0, ktrace = 0;
  42 static int short_format = 0;
  43
  44 /****************************************************************************/
  45
  46 void
  47 transferr(FILE *ifp, FILE *ofp, int count)
  48 {
  49         int n, num;
  50
  51         while (count == -1 || count > 0) {
  52                 if (count == -1 || count > sizeof(cmd))
  53                         num = sizeof(cmd);
  54                 else
  55                         num = count;
  56                 n = fread(cmd, 1, num, ifp);
  57                 if (n == 0)
  58                         break;
  59                 if (fwrite(cmd, n, 1, ofp) != 1) {
  60                         fprintf(stderr, "Write failed :-(\n");
  61                         exit(1);
  62                 }
  63                 if (count != -1)
  64                         count -= n;
  65         }
  66         if (count > 0) {
  67                 fprintf(stderr, "Failed to transferr %d bytes\n", count);
  68                 exit(1);
  69         }
  70 }
  71
  72 /****************************************************************************/
  73
  74 void
  75 process_file(char *ifile, char *ofile)
  76 {
  77         int old_flags, old_stack, new_flags, new_stack;
  78         FILE *ifp, *ofp;
  79         int ofp_is_pipe = 0;
  80         struct flat_hdr old_hdr, new_hdr;
  81         char tfile[256];
  82         char tfile2[256];
  83
  84         *tfile = *tfile2 = '\0';
  85
  86         if ((ifp = fopen(ifile, "rb")) == NULL) {
  87                 fprintf(stderr, "Cannot open %s\n", ifile);
  88                 return;
  89         }
  90
  91         if (fread(&old_hdr, sizeof(old_hdr), 1, ifp) != 1) {
  92                 fprintf(stderr, "Cannot read header of %s\n", ifile);
  93                 return;
  94         }
  95
  96         if (strncmp(old_hdr.magic, "bFLT", 4) != 0) {
  97                 fprintf(stderr, "Cannot read header of %s\n", ifile);
  98                 return;
  99         }
 100
 101         new_flags = old_flags = ntohl(old_hdr.flags);
 102         new_stack = old_stack = ntohl(old_hdr.stack_size);
 103         new_hdr = old_hdr;
 104
 105         if (compress == 1) {
 106                 new_flags |= FLAT_FLAG_GZIP;
 107                 new_flags &= ~FLAT_FLAG_GZDATA;
 108         } else if (compress == 2) {
 109                 new_flags |= FLAT_FLAG_GZDATA;
 110                 new_flags &= ~FLAT_FLAG_GZIP;
 111         } else if (compress < 0)
 112                 new_flags &= ~(FLAT_FLAG_GZIP|FLAT_FLAG_GZDATA);
 113
 114         if (ramload > 0)
 115                 new_flags |= FLAT_FLAG_RAM;
 116         else if (ramload < 0)
 117                 new_flags &= ~FLAT_FLAG_RAM;
 118
 119         if (ktrace > 0)
 120                 new_flags |= FLAT_FLAG_KTRACE;
 121         else if (ktrace < 0)
 122                 new_flags &= ~FLAT_FLAG_KTRACE;
 123
 124         if (stacksize)
 125                 new_stack = stacksize;
 126
 127         if (print == 1) {
 128                 time_t t;
 129
 130                 printf("%s\n", ifile);
 131                 printf("    Magic:        %4.4s\n", old_hdr.magic);
 132                 printf("    Rev:          %d\n",    ntohl(old_hdr.rev));
 133                 t = (time_t) htonl(old_hdr.build_date);
 134                 printf("    Build Date:   %s",      t?ctime(&t):"not specified\n");
 135                 printf("    Entry:        0x%x\n",  ntohl(old_hdr.entry));
 136                 printf("    Data Start:   0x%x\n",  ntohl(old_hdr.data_start));
 137                 printf("    Data End:     0x%x\n",  ntohl(old_hdr.data_end));
 138                 printf("    BSS End:      0x%x\n",  ntohl(old_hdr.bss_end));
 139                 printf("    Stack Size:   0x%x\n",  ntohl(old_hdr.stack_size));
 140                 printf("    Reloc Start:  0x%x\n",  ntohl(old_hdr.reloc_start));
 141                 printf("    Reloc Count:  0x%x\n",  ntohl(old_hdr.reloc_count));
 142                 printf("    Flags:        0x%x ( ",  ntohl(old_hdr.flags));
 143                 if (old_flags) {
 144                         if (old_flags & FLAT_FLAG_RAM)
 145                                 printf("Load-to-Ram ");
 146                         if (old_flags & FLAT_FLAG_GOTPIC)
 147                                 printf("Has-PIC-GOT ");
 148                         if (old_flags & FLAT_FLAG_GZIP)
 149                                 printf("Gzip-Compressed ");
 150                         if (old_flags & FLAT_FLAG_GZDATA)
 151                                 printf("Gzip-Data-Compressed ");
 152                         if (old_flags & FLAT_FLAG_KTRACE)
 153                                 printf("Kernel-Traced-Load ");
 154                         printf(")\n");
 155                 }
 156         } else if (print > 1) {
 157                 static int first = 1;
 158                 unsigned int text, data, bss, stk, rel, tot;
 159
 160                 if (first) {
 161                         printf("Flag Rev   Text   Data    BSS  Stack Relocs    RAM Filename\n");
 162                         printf("-----------------------------------------------------------\n");
 163                         first = 0;
 164                 }
 165                 *tfile = '\0';
 166                 strcat(tfile, (old_flags & FLAT_FLAG_KTRACE) ? "k" : "");
 167                 strcat(tfile, (old_flags & FLAT_FLAG_RAM) ? "r" : "");
 168                 strcat(tfile, (old_flags & FLAT_FLAG_GOTPIC) ? "p" : "");
 169                 strcat(tfile, (old_flags & FLAT_FLAG_GZIP) ? "z" :
 170                                         ((old_flags & FLAT_FLAG_GZDATA) ? "d" : ""));
 171                 printf("-%-3.3s ", tfile);
 172                 printf("%3d ", ntohl(old_hdr.rev));
 173                 printf("%6d ", text=ntohl(old_hdr.data_start)-sizeof(struct flat_hdr));
 174                 printf("%6d ", data=ntohl(old_hdr.data_end)-ntohl(old_hdr.data_start));
 175                 printf("%6d ", bss=ntohl(old_hdr.bss_end)-ntohl(old_hdr.data_end));
 176                 printf("%6d ", stk=ntohl(old_hdr.stack_size));
 177                 printf("%6d ", rel=ntohl(old_hdr.reloc_count) * 4);
 178                 /*
 179                  * work out how much RAM is needed per invocation, this
 180                  * calculation is dependent on the binfmt_flat implementation
 181                  */
 182                 tot = data; /* always need data */
 183
 184                 if (old_flags & (FLAT_FLAG_RAM|FLAT_FLAG_GZIP))
 185                         tot += text + sizeof(struct flat_hdr);
 186
 187                 if (bss + stk > rel) /* which is bigger ? */
 188                         tot += bss + stk;
 189                 else
 190                         tot += rel;
 191
 192                 printf("%6d ", tot);
 193                 /*
 194                  * the total depends on whether the relocs are smaller/bigger than
 195                  * the BSS
 196                  */
 197                 printf("%s\n", ifile);
 198         }
 199
 200         /* if there is nothing else to do, leave */
 201         if (new_flags == old_flags && new_stack == old_stack)
 202                 return;
 203
 204         new_hdr.flags = htonl(new_flags);
 205         new_hdr.stack_size = htonl(new_stack);
 206
 207         strcpy(tfile, "/tmp/flatXXXXXX");
 208         mkstemp(tfile);
 209         if ((ofp = fopen(tfile, "wb")) == NULL) {
 210                 fprintf(stderr, "Failed to open %s for writing\n", tfile);
 211                 unlink(tfile);
 212                 unlink(tfile2);
 213                 exit(1);
 214         }
 215
 216         if (fwrite(&new_hdr, sizeof(new_hdr), 1, ofp) != 1) {
 217                 fprintf(stderr, "Failed to write to  %s\n", tfile);
 218                 unlink(tfile);
 219                 unlink(tfile2);
 220                 exit(1);
 221         }
 222
 223         /*
 224          * get ourselves a fully uncompressed copy of the text/data/relocs
 225          * so that we can manipulate it more easily
 226          */
 227         if (old_flags & (FLAT_FLAG_GZIP|FLAT_FLAG_GZDATA)) {
 228                 FILE *tfp;
 229
 230                 strcpy(tfile2, "/tmp/flat2XXXXXX");
 231                 mkstemp(tfile2);
 232
 233                 if (old_flags & FLAT_FLAG_GZDATA) {
 234                         tfp = fopen(tfile2, "wb");
 235                         if (!tfp) {
 236                                 fprintf(stderr, "Failed to open %s for writing\n", tfile2);
 237                                 exit(1);
 238                         }
 239                         transferr(ifp, tfp, ntohl(old_hdr.data_start) -
 240                                         sizeof(struct flat_hdr));
 241                         fclose(tfp);
 242                 }
 243
 244                 sprintf(cmd, "gunzip >> %s", tfile2);
 245                 tfp = popen(cmd, "wb");
 246                 if(!tfp) {
 247                         perror("popen");
 248                         exit(1);
 249                 }
 250                 transferr(ifp, tfp, -1);
 251                 pclose(tfp);
 252
 253                 fclose(ifp);
 254                 ifp = fopen(tfile2, "rb");
 255                 if (!ifp) {
 256                         fprintf(stderr, "Failed to open %s for reading\n", tfile2);
 257                         unlink(tfile);
 258                         unlink(tfile2);
 259                         exit(1);
 260                 }
 261         }
 262
 263         if (new_flags & FLAT_FLAG_GZIP) {
 264                 printf("zflat %s --> %s\n", ifile, ofile);
 265                 fclose(ofp);
 266                 sprintf(cmd, "gzip -9 -f >> %s", tfile);
 267                 ofp = popen(cmd, "wb");
 268                 ofp_is_pipe = 1;
 269         } else if (new_flags & FLAT_FLAG_GZDATA) {
 270                 printf("zflat-data %s --> %s\n", ifile, ofile);
 271                 transferr(ifp, ofp, ntohl(new_hdr.data_start) -
 272                                 sizeof(struct flat_hdr));
 273                 fclose(ofp);
 274                 sprintf(cmd, "gzip -9 -f >> %s", tfile);
 275                 ofp = popen(cmd, "wb");
 276                 ofp_is_pipe = 1;
 277         }
 278
 279         if (!ofp) { /* can only happen if using gzip/gunzip */
 280                 fprintf(stderr, "Can't run cmd %s\n", cmd);
 281                 unlink(tfile);
 282                 unlink(tfile2);
 283                 exit(1);
 284         }
 285
 286         transferr(ifp, ofp, -1);
 287
 288         if (ferror(ifp) || ferror(ofp)) {
 289                 fprintf(stderr, "Error on file pointer%s%s\n",
 290                                 ferror(ifp) ? " input" : "", ferror(ofp) ? " output" : "");
 291                 unlink(tfile);
 292                 unlink(tfile2);
 293                 exit(1);
 294         }
 295
 296         fclose(ifp);
 297         if (ofp_is_pipe)
 298                 pclose(ofp);
 299         else
 300                 fclose(ofp);
 301
 302         /* cheat a little here to preserve file permissions */
 303         sprintf(cmd, "cp %s %s", tfile, ofile);
 304         system(cmd);
 305         unlink(tfile);
 306         unlink(tfile2);
 307 }
 308
 309 /****************************************************************************/
 310
 311 void
 312 usage(char *s)
 313 {
 314         if (s)
 315                 fprintf(stderr, "%s\n", s);
 316         fprintf(stderr, "usage: %s [options] flat-file\n", program_name);
 317         fprintf(stderr, "       Allows you to change an existing flat file\n\n");
 318         fprintf(stderr, "       -p      : print current settings\n");
 319         fprintf(stderr, "       -z      : compressed flat file\n");
 320         fprintf(stderr, "       -d      : compressed data-only flat file\n");
 321         fprintf(stderr, "       -Z      : un-compressed flat file\n");
 322         fprintf(stderr, "       -r      : ram load\n");
 323         fprintf(stderr, "       -R      : do not RAM load\n");
 324         fprintf(stderr, "       -k      : kernel traced load (for debug)\n");
 325         fprintf(stderr, "       -K      : normal non-kernel traced load\n");
 326         fprintf(stderr, "       -s size : stack size\n");
 327         fprintf(stderr, "       -o file : output-file\n"
 328                         "                 (default is to modify input file)\n");
 329         exit(1);
 330 }
 331
 332 /****************************************************************************/
 333
 334 int
 335 main(int argc, char *argv[])
 336 {
 337         int c;
 338         char *ofile = NULL, *ifile;
 339
 340         program_name = argv[0];
 341
 342         while ((c = getopt(argc, argv, "pdzZrRkKs:o:")) != EOF) {
 343                 switch (c) {
 344                 case 'p': print = 1;                break;
 345                 case 'z': compress = 1;             break;
 346                 case 'd': compress = 2;             break;
 347                 case 'Z': compress = -1;            break;
 348                 case 'r': ramload = 1;              break;
 349                 case 'R': ramload = -1;             break;
 350                 case 'k': ktrace = 1;               break;
 351                 case 'K': ktrace = -1;              break;
 352                 case 's': stacksize = atoi(optarg); break;
 353                 case 'o': ofile = optarg;           break;
 354                 default:
 355                         usage("invalid option");
 356                         break;
 357                 }
 358         }
 359
 360         if (optind >= argc)
 361                 usage("No input files provided");
 362
 363         if (ofile && argc - optind > 1)
 364                 usage("-o can only be used with a single file");
 365
 366         if (!print && !compress && !ramload && !stacksize) /* no args == print */
 367                 print = argc - optind; /* greater than 1 is short format */
 368
 369         for (c = optind; c < argc; c++) {
 370                 ifile = argv[c];
 371                 if (!ofile)
 372                         ofile = ifile;
 373                 process_file(ifile, ofile);
 374                 ofile = NULL;
 375         }
 376
 377         exit(0);
 378 }
 379
 380 /****************************************************************************/