tools/firmware-utils/src/ptgen.c

   1 /*
   2  * ptgen - partition table generator
   3  * Copyright (C) 2006 by Felix Fietkau <nbd@openwrt.org>
   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 <ctype.h>
  30 #include <fcntl.h>
  31
  32 #if __BYTE_ORDER == __BIG_ENDIAN
  33 #define cpu_to_le16(x) bswap_16(x)
  34 #elif __BYTE_ORDER == __LITTLE_ENDIAN
  35 #define cpu_to_le16(x) (x)
  36 #else
  37 #error unknown endianness!
  38 #endif
  39
  40 /* Partition table entry */
  41 struct pte {
  42         unsigned char active;
  43         unsigned char chs_start[3];
  44         unsigned char type;
  45         unsigned char chs_end[3];
  46         unsigned int start;
  47         unsigned int length;
  48 };
  49
  50 struct partinfo {
  51         unsigned long size;
  52         int type;
  53 };
  54
  55 int verbose = 0;
  56 int active = 1;
  57 int heads = -1;
  58 int sectors = -1;
  59 int kb_align = 0;
  60 struct partinfo parts[4];
  61 char *filename = NULL;
  62
  63
  64 /*
  65  * parse the size argument, which is either
  66  * a simple number (K assumed) or
  67  * K, M or G
  68  *
  69  * returns the size in KByte
  70  */
  71 static long to_kbytes(const char *string) {
  72         int exp = 0;
  73         long result;
  74         char *end;
  75
  76         result = strtoul(string, &end, 0);
  77         switch (tolower(*end)) {
  78                         case 'k' :
  79                         case '\0' : exp = 0; break;
  80                         case 'm' : exp = 1; break;
  81                         case 'g' : exp = 2; break;
  82                         default: return 0;
  83         }
  84
  85         if (*end)
  86                 end++;
  87
  88         if (*end) {
  89                 fprintf(stderr, "garbage after end of number\n");
  90                 return 0;
  91         }
  92
  93         /* result: number + 1024^(exp) */
  94         return result * ((2 << ((10 * exp) - 1)) ?: 1);
  95 }
  96
  97 /* convert the sector number into a CHS value for the partition table */
  98 static void to_chs(long sect, unsigned char chs[3]) {
  99         int c,h,s;
 100
 101         s = (sect % sectors) + 1;
 102         sect = sect / sectors;
 103         h = sect % heads;
 104         sect = sect / heads;
 105         c = sect;
 106
 107         chs[0] = h;
 108         chs[1] = s | ((c >> 2) & 0xC0);
 109         chs[2] = c & 0xFF;
 110
 111         return;
 112 }
 113
 114 /* round the sector number up to the next cylinder */
 115 static inline unsigned long round_to_cyl(long sect) {
 116         int cyl_size = heads * sectors;
 117
 118         return sect + cyl_size - (sect % cyl_size);
 119 }
 120
 121 /* round the sector number up to the kb_align boundary */
 122 static inline unsigned long round_to_kb(long sect) {
 123         return ((sect - 1) / kb_align + 1) * kb_align;
 124 }
 125
 126 /* check the partition sizes and write the partition table */
 127 static int gen_ptable(int nr)
 128 {
 129         struct pte pte[4];
 130         unsigned long sect = 0;
 131         int i, fd, ret = -1, start, len;
 132
 133         memset(pte, 0, sizeof(struct pte) * 4);
 134         for (i = 0; i < nr; i++) {
 135                 if (!parts[i].size) {
 136                         fprintf(stderr, "Invalid size in partition %d!\n", i);
 137                         return -1;
 138                 }
 139                 pte[i].active = ((i + 1) == active) ? 0x80 : 0;
 140                 pte[i].type = parts[i].type;
 141                 start = sect + sectors;
 142                 if (kb_align != 0)
 143                         start = round_to_kb(start);
 144                 pte[i].start = cpu_to_le16(start);
 145                 sect = start + parts[i].size * 2;
 146                 if (kb_align == 0)
 147                         sect = round_to_cyl(sect);
 148                 pte[i].length = cpu_to_le16(len = sect - start);
 149                 to_chs(start, pte[i].chs_start);
 150                 to_chs(start + len - 1, pte[i].chs_end);
 151                 if (verbose)
 152                         fprintf(stderr, "Partition %d: start=%ld, end=%ld, size=%ld\n", i, (long) start * 512, ((long) start + (long) len) * 512, (long) len * 512);
 153                 printf("%ld\n", ((long) start * 512));
 154                 printf("%ld\n", ((long) len * 512));
 155         }
 156
 157         if ((fd = open(filename, O_WRONLY|O_CREAT|O_TRUNC, 0644)) < 0) {
 158                 fprintf(stderr, "Can't open output file '%s'\n",filename);
 159                 return -1;
 160         }
 161
 162         lseek(fd, 446, SEEK_SET);
 163         if (write(fd, pte, sizeof(struct pte) * 4) != sizeof(struct pte) * 4) {
 164                 fprintf(stderr, "write failed.\n");
 165                 goto fail;
 166         }
 167         lseek(fd, 510, SEEK_SET);
 168         if (write(fd, "\x55\xaa", 2) != 2) {
 169                 fprintf(stderr, "write failed.\n");
 170                 goto fail;
 171         }
 172
 173         ret = 0;
 174 fail:
 175         close(fd);
 176         return ret;
 177 }
 178
 179 static void usage(char *prog)
 180 {
 181         fprintf(stderr, "Usage: %s [-v] -h <heads> -s <sectors> -o <outputfile> [-a 0..4] [-l <align kB>] [[-t <type>] -p <size>...] \n", prog);
 182         exit(1);
 183 }
 184
 185 int main (int argc, char **argv)
 186 {
 187         char type = 0x83;
 188         int ch;
 189         int part = 0;
 190
 191         while ((ch = getopt(argc, argv, "h:s:p:a:t:o:vl:")) != -1) {
 192                 switch (ch) {
 193                 case 'o':
 194                         filename = optarg;
 195                         break;
 196                 case 'v':
 197                         verbose++;
 198                         break;
 199                 case 'h':
 200                         heads = (int) strtoul(optarg, NULL, 0);
 201                         break;
 202                 case 's':
 203                         sectors = (int) strtoul(optarg, NULL, 0);
 204                         break;
 205                 case 'p':
 206                         if (part > 3) {
 207                                 fprintf(stderr, "Too many partitions\n");
 208                                 exit(1);
 209                         }
 210                         parts[part].size = to_kbytes(optarg);
 211                         parts[part++].type = type;
 212                         break;
 213                 case 't':
 214                         type = (char) strtoul(optarg, NULL, 16);
 215                         break;
 216                 case 'a':
 217                         active = (int) strtoul(optarg, NULL, 0);
 218                         if ((active < 0) || (active > 4))
 219                                 active = 0;
 220                         break;
 221                 case 'l':
 222                         kb_align = (int) strtoul(optarg, NULL, 0) * 2;
 223                         break;
 224                 case '?':
 225                 default:
 226                         usage(argv[0]);
 227                 }
 228         }
 229         argc -= optind;
 230         if (argc || (heads <= 0) || (sectors <= 0) || !filename)
 231                 usage(argv[0]);
 232
 233         return gen_ptable(part);
 234 }