tools/firmware-utils/src/ptgen.c

   1 /*
   2  * ptgen - partition table generator
   3  * Copyright (C) 2006 by Felix Fietkau <nbd@nbd.name>
   4  *
   5  * uses parts of afdisk
   6  * Copyright (C) 2002 by David Roetzel <david@roetzel.de>
   7  *
   8  * This program is free software; you can redistribute it and/or modify
   9  * it under the terms of the GNU General Public License as published by
  10  * the Free Software Foundation; either version 2 of the License, or
  11  * (at your option) any later version.
  12  *
  13  * This program is distributed in the hope that it will be useful,
  14  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  15  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  16  * GNU General Public License for more details.
  17  *
  18  * You should have received a copy of the GNU General Public License
  19  * along with this program; if not, write to the Free Software
  20  * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
  21  */
  22
  23 #include <sys/types.h>
  24 #include <sys/stat.h>
  25 #include <string.h>
  26 #include <unistd.h>
  27 #include <stdlib.h>
  28 #include <stdio.h>
  29 #include <stdint.h>
  30 #include <ctype.h>
  31 #include <fcntl.h>
  32 #include <stdint.h>
  33
  34 #if __BYTE_ORDER == __BIG_ENDIAN
  35 #define cpu_to_le32(x) bswap_32(x)
  36 #elif __BYTE_ORDER == __LITTLE_ENDIAN
  37 #define cpu_to_le32(x) (x)
  38 #else
  39 #error unknown endianness!
  40 #endif
  41
  42 /* Partition table entry */
  43 struct pte {
  44         uint8_t active;
  45         uint8_t chs_start[3];
  46         uint8_t type;
  47         uint8_t chs_end[3];
  48         uint32_t start;
  49         uint32_t length;
  50 };
  51
  52 struct partinfo {
  53         unsigned long size;
  54         int type;
  55 };
  56
  57 int verbose = 0;
  58 int active = 1;
  59 int heads = -1;
  60 int sectors = -1;
  61 int kb_align = 0;
  62 struct partinfo parts[4];
  63 char *filename = NULL;
  64
  65
  66 /*
  67  * parse the size argument, which is either
  68  * a simple number (K assumed) or
  69  * K, M or G
  70  *
  71  * returns the size in KByte
  72  */
  73 static long to_kbytes(const char *string) {
  74         int exp = 0;
  75         long result;
  76         char *end;
  77
  78         result = strtoul(string, &end, 0);
  79         switch (tolower(*end)) {
  80                         case 'k' :
  81                         case '\0' : exp = 0; break;
  82                         case 'm' : exp = 1; break;
  83                         case 'g' : exp = 2; break;
  84                         default: return 0;
  85         }
  86
  87         if (*end)
  88                 end++;
  89
  90         if (*end) {
  91                 fprintf(stderr, "garbage after end of number\n");
  92                 return 0;
  93         }
  94
  95         /* result: number + 1024^(exp) */
  96         if (exp == 0)
  97                 return result;
  98         return result * (2 << ((10 * exp) - 1));
  99 }
 100
 101 /* convert the sector number into a CHS value for the partition table */
 102 static void to_chs(long sect, unsigned char chs[3]) {
 103         int c,h,s;
 104
 105         s = (sect % sectors) + 1;
 106         sect = sect / sectors;
 107         h = sect % heads;
 108         sect = sect / heads;
 109         c = sect;
 110
 111         chs[0] = h;
 112         chs[1] = s | ((c >> 2) & 0xC0);
 113         chs[2] = c & 0xFF;
 114
 115         return;
 116 }
 117
 118 /* round the sector number up to the next cylinder */
 119 static inline unsigned long round_to_cyl(long sect) {
 120         int cyl_size = heads * sectors;
 121
 122         return sect + cyl_size - (sect % cyl_size);
 123 }
 124
 125 /* round the sector number up to the kb_align boundary */
 126 static inline unsigned long round_to_kb(long sect) {
 127         return ((sect - 1) / kb_align + 1) * kb_align;
 128 }
 129
 130 /* check the partition sizes and write the partition table */
 131 static int gen_ptable(uint32_t signature, int nr)
 132 {
 133         struct pte pte[4];
 134         unsigned long sect = 0;
 135         int i, fd, ret = -1, start, len;
 136
 137         memset(pte, 0, sizeof(struct pte) * 4);
 138         for (i = 0; i < nr; i++) {
 139                 if (!parts[i].size) {
 140                         fprintf(stderr, "Invalid size in partition %d!\n", i);
 141                         return -1;
 142                 }
 143                 pte[i].active = ((i + 1) == active) ? 0x80 : 0;
 144                 pte[i].type = parts[i].type;
 145                 start = sect + sectors;
 146                 if (kb_align != 0)
 147                         start = round_to_kb(start);
 148                 pte[i].start = cpu_to_le32(start);
 149                 sect = start + parts[i].size * 2;
 150                 if (kb_align == 0)
 151                         sect = round_to_cyl(sect);
 152                 pte[i].length = cpu_to_le32(len = sect - start);
 153                 to_chs(start, pte[i].chs_start);
 154                 to_chs(start + len - 1, pte[i].chs_end);
 155                 if (verbose)
 156                         fprintf(stderr, "Partition %d: start=%ld, end=%ld, size=%ld\n", i, (long) start * 512, ((long) start + (long) len) * 512, (long) len * 512);
 157                 printf("%ld\n", ((long) start * 512));
 158                 printf("%ld\n", ((long) len * 512));
 159         }
 160
 161         if ((fd = open(filename, O_WRONLY|O_CREAT|O_TRUNC, 0644)) < 0) {
 162                 fprintf(stderr, "Can't open output file '%s'\n",filename);
 163                 return -1;
 164         }
 165
 166         lseek(fd, 440, SEEK_SET);
 167         if (write(fd, &signature, sizeof(signature)) != sizeof(signature)) {
 168                 fprintf(stderr, "write failed.\n");
 169                 goto fail;
 170         }
 171
 172         lseek(fd, 446, SEEK_SET);
 173         if (write(fd, pte, sizeof(struct pte) * 4) != sizeof(struct pte) * 4) {
 174                 fprintf(stderr, "write failed.\n");
 175                 goto fail;
 176         }
 177         lseek(fd, 510, SEEK_SET);
 178         if (write(fd, "\x55\xaa", 2) != 2) {
 179                 fprintf(stderr, "write failed.\n");
 180                 goto fail;
 181         }
 182
 183         ret = 0;
 184 fail:
 185         close(fd);
 186         return ret;
 187 }
 188
 189 static void usage(char *prog)
 190 {
 191         fprintf(stderr, "Usage: %s [-v] -h <heads> -s <sectors> -o <outputfile> [-a 0..4] [-l <align kB>] [[-t <type>] -p <size>...] \n", prog);
 192         exit(1);
 193 }
 194
 195 int main (int argc, char **argv)
 196 {
 197         char type = 0x83;
 198         int ch;
 199         int part = 0;
 200         uint32_t signature = 0x5452574F; /* 'OWRT' */
 201
 202         while ((ch = getopt(argc, argv, "h:s:p:a:t:o:vl:S:")) != -1) {
 203                 switch (ch) {
 204                 case 'o':
 205                         filename = optarg;
 206                         break;
 207                 case 'v':
 208                         verbose++;
 209                         break;
 210                 case 'h':
 211                         heads = (int) strtoul(optarg, NULL, 0);
 212                         break;
 213                 case 's':
 214                         sectors = (int) strtoul(optarg, NULL, 0);
 215                         break;
 216                 case 'p':
 217                         if (part > 3) {
 218                                 fprintf(stderr, "Too many partitions\n");
 219                                 exit(1);
 220                         }
 221                         parts[part].size = to_kbytes(optarg);
 222                         parts[part++].type = type;
 223                         break;
 224                 case 't':
 225                         type = (char) strtoul(optarg, NULL, 16);
 226                         break;
 227                 case 'a':
 228                         active = (int) strtoul(optarg, NULL, 0);
 229                         if ((active < 0) || (active > 4))
 230                                 active = 0;
 231                         break;
 232                 case 'l':
 233                         kb_align = (int) strtoul(optarg, NULL, 0) * 2;
 234                         break;
 235                 case 'S':
 236                         signature = strtoul(optarg, NULL, 0);
 237                         break;
 238                 case '?':
 239                 default:
 240                         usage(argv[0]);
 241                 }
 242         }
 243         argc -= optind;
 244         if (argc || (heads <= 0) || (sectors <= 0) || !filename)
 245                 usage(argv[0]);
 246
 247         return gen_ptable(signature, part);
 248 }