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 {
  75         int exp = 0;
  76         long result;
  77         char *end;
  78
  79         result = strtoul(string, &end, 0);
  80         switch (tolower(*end)) {
  81                 case 'k' :
  82                 case '\0' : exp = 0; break;
  83                 case 'm' : exp = 1; break;
  84                 case 'g' : exp = 2; break;
  85                 default: return 0;
  86         }
  87
  88         if (*end)
  89                 end++;
  90
  91         if (*end) {
  92                 fprintf(stderr, "garbage after end of number\n");
  93                 return 0;
  94         }
  95
  96         /* result: number + 1024^(exp) */
  97         if (exp == 0)
  98                 return result;
  99         return result * (2 << ((10 * exp) - 1));
 100 }
 101
 102 /* convert the sector number into a CHS value for the partition table */
 103 static void to_chs(long sect, unsigned char chs[3])
 104 {
 105         int c,h,s;
 106
 107         s = (sect % sectors) + 1;
 108         sect = sect / sectors;
 109         h = sect % heads;
 110         sect = sect / heads;
 111         c = sect;
 112
 113         chs[0] = h;
 114         chs[1] = s | ((c >> 2) & 0xC0);
 115         chs[2] = c & 0xFF;
 116
 117         return;
 118 }
 119
 120 /* round the sector number up to the next cylinder */
 121 static inline unsigned long round_to_cyl(long sect)
 122 {
 123         int cyl_size = heads * sectors;
 124
 125         return sect + cyl_size - (sect % cyl_size);
 126 }
 127
 128 /* round the sector number up to the kb_align boundary */
 129 static inline unsigned long round_to_kb(long sect) {
 130         return ((sect - 1) / kb_align + 1) * kb_align;
 131 }
 132
 133 /* check the partition sizes and write the partition table */
 134 static int gen_ptable(uint32_t signature, int nr)
 135 {
 136         struct pte pte[4];
 137         unsigned long sect = 0;
 138         int i, fd, ret = -1, start, len;
 139
 140         memset(pte, 0, sizeof(struct pte) * 4);
 141         for (i = 0; i < nr; i++) {
 142                 if (!parts[i].size) {
 143                         fprintf(stderr, "Invalid size in partition %d!\n", i);
 144                         return -1;
 145                 }
 146
 147                 pte[i].active = ((i + 1) == active) ? 0x80 : 0;
 148                 pte[i].type = parts[i].type;
 149
 150                 start = sect + sectors;
 151                 if (kb_align != 0)
 152                         start = round_to_kb(start);
 153                 pte[i].start = cpu_to_le32(start);
 154
 155                 sect = start + parts[i].size * 2;
 156                 if (kb_align == 0)
 157                         sect = round_to_cyl(sect);
 158                 pte[i].length = cpu_to_le32(len = sect - start);
 159
 160                 to_chs(start, pte[i].chs_start);
 161                 to_chs(start + len - 1, pte[i].chs_end);
 162
 163                 if (verbose)
 164                         fprintf(stderr, "Partition %d: start=%ld, end=%ld, size=%ld\n", i, (long)start * 512, ((long)start + (long)len) * 512, (long)len * 512);
 165                 printf("%ld\n", (long)start * 512);
 166                 printf("%ld\n", (long)len * 512);
 167         }
 168
 169         if ((fd = open(filename, O_WRONLY|O_CREAT|O_TRUNC, 0644)) < 0) {
 170                 fprintf(stderr, "Can't open output file '%s'\n",filename);
 171                 return -1;
 172         }
 173
 174         lseek(fd, 440, SEEK_SET);
 175         if (write(fd, &signature, sizeof(signature)) != sizeof(signature)) {
 176                 fprintf(stderr, "write failed.\n");
 177                 goto fail;
 178         }
 179
 180         lseek(fd, 446, SEEK_SET);
 181         if (write(fd, pte, sizeof(struct pte) * 4) != sizeof(struct pte) * 4) {
 182                 fprintf(stderr, "write failed.\n");
 183                 goto fail;
 184         }
 185         lseek(fd, 510, SEEK_SET);
 186         if (write(fd, "\x55\xaa", 2) != 2) {
 187                 fprintf(stderr, "write failed.\n");
 188                 goto fail;
 189         }
 190
 191         ret = 0;
 192 fail:
 193         close(fd);
 194         return ret;
 195 }
 196
 197 static void usage(char *prog)
 198 {
 199         fprintf(stderr, "Usage: %s [-v] -h <heads> -s <sectors> -o <outputfile> [-a 0..4] [-l <align kB>] [[-t <type>] -p <size>...] \n", prog);
 200         exit(EXIT_FAILURE);
 201 }
 202
 203 int main (int argc, char **argv)
 204 {
 205         char type = 0x83;
 206         int ch;
 207         int part = 0;
 208         uint32_t signature = 0x5452574F; /* 'OWRT' */
 209
 210         while ((ch = getopt(argc, argv, "h:s:p:a:t:o:vl:S:")) != -1) {
 211                 switch (ch) {
 212                 case 'o':
 213                         filename = optarg;
 214                         break;
 215                 case 'v':
 216                         verbose++;
 217                         break;
 218                 case 'h':
 219                         heads = (int)strtoul(optarg, NULL, 0);
 220                         break;
 221                 case 's':
 222                         sectors = (int)strtoul(optarg, NULL, 0);
 223                         break;
 224                 case 'p':
 225                         if (part > 3) {
 226                                 fprintf(stderr, "Too many partitions\n");
 227                                 exit(EXIT_FAILURE);
 228                         }
 229                         parts[part].size = to_kbytes(optarg);
 230                         parts[part++].type = type;
 231                         break;
 232                 case 't':
 233                         type = (char)strtoul(optarg, NULL, 16);
 234                         break;
 235                 case 'a':
 236                         active = (int)strtoul(optarg, NULL, 0);
 237                         if ((active < 0) || (active > 4))
 238                                 active = 0;
 239                         break;
 240                 case 'l':
 241                         kb_align = (int)strtoul(optarg, NULL, 0) * 2;
 242                         break;
 243                 case 'S':
 244                         signature = strtoul(optarg, NULL, 0);
 245                         break;
 246                 case '?':
 247                 default:
 248                         usage(argv[0]);
 249                 }
 250         }
 251         argc -= optind;
 252         if (argc || (heads <= 0) || (sectors <= 0) || !filename)
 253                 usage(argv[0]);
 254
 255         return gen_ptable(signature, part) ? EXIT_FAILURE : EXIT_SUCCESS;
 256 }