flthdr.c

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