release/src/router/busybox/e2fsprogs/ext2fs/getsize.c

   1 /* vi: set sw=4 ts=4: */
   2 /*
   3  * getsize.c --- get the size of a partition.
   4  *
   5  * Copyright (C) 1995, 1995 Theodore Ts'o.
   6  * Copyright (C) 2003 VMware, Inc.
   7  *
   8  * Windows version of ext2fs_get_device_size by Chris Li, VMware.
   9  *
  10  * %Begin-Header%
  11  * This file may be redistributed under the terms of the GNU Public
  12  * License.
  13  * %End-Header%
  14  */
  15
  16 #include <stdio.h>
  17 #if HAVE_UNISTD_H
  18 #include <unistd.h>
  19 #endif
  20 #if HAVE_ERRNO_H
  21 #include <errno.h>
  22 #endif
  23 #include <fcntl.h>
  24 #ifdef HAVE_SYS_IOCTL_H
  25 #include <sys/ioctl.h>
  26 #endif
  27 #ifdef HAVE_LINUX_FD_H
  28 #include <linux/fd.h>
  29 #endif
  30 #ifdef HAVE_SYS_DISKLABEL_H
  31 #include <sys/disklabel.h>
  32 #endif
  33 #ifdef HAVE_SYS_DISK_H
  34 #ifdef HAVE_SYS_QUEUE_H
  35 #include <sys/queue.h> /* for LIST_HEAD */
  36 #endif
  37 #include <sys/disk.h>
  38 #endif
  39 #ifdef __linux__
  40 #include <sys/utsname.h>
  41 #endif
  42
  43 #if defined(__linux__) && defined(_IO) && !defined(BLKGETSIZE)
  44 #define BLKGETSIZE _IO(0x12,96) /* return device size */
  45 #endif
  46
  47 #if defined(__linux__) && defined(_IOR) && !defined(BLKGETSIZE64)
  48 #define BLKGETSIZE64 _IOR(0x12,114,size_t)      /* return device size in bytes (u64 *arg) */
  49 #endif
  50
  51 #ifdef APPLE_DARWIN
  52 #define BLKGETSIZE DKIOCGETBLOCKCOUNT32
  53 #endif /* APPLE_DARWIN */
  54
  55 #include "ext2_fs.h"
  56 #include "ext2fs.h"
  57
  58 #if defined(__CYGWIN__) || defined(WIN32)
  59 #include <windows.h>
  60 #include <winioctl.h>
  61
  62 #if (_WIN32_WINNT >= 0x0500)
  63 #define HAVE_GET_FILE_SIZE_EX 1
  64 #endif
  65
  66 errcode_t ext2fs_get_device_size(const char *file, int blocksize,
  67                                  blk_t *retblocks)
  68 {
  69         HANDLE dev;
  70         PARTITION_INFORMATION pi;
  71         DISK_GEOMETRY gi;
  72         DWORD retbytes;
  73 #ifdef HAVE_GET_FILE_SIZE_EX
  74         LARGE_INTEGER filesize;
  75 #else
  76         DWORD filesize;
  77 #endif /* HAVE_GET_FILE_SIZE_EX */
  78
  79         dev = CreateFile(file, GENERIC_READ,
  80                          FILE_SHARE_READ | FILE_SHARE_WRITE ,
  81                          NULL, OPEN_EXISTING, FILE_ATTRIBUTE_NORMAL, NULL);
  82
  83         if (dev == INVALID_HANDLE_VALUE)
  84                 return EBADF;
  85         if (DeviceIoControl(dev, IOCTL_DISK_GET_PARTITION_INFO,
  86                             &pi, sizeof(PARTITION_INFORMATION),
  87                             &pi, sizeof(PARTITION_INFORMATION),
  88                             &retbytes, NULL)) {
  89
  90                 *retblocks = pi.PartitionLength.QuadPart / blocksize;
  91
  92         } else if (DeviceIoControl(dev, IOCTL_DISK_GET_DRIVE_GEOMETRY,
  93                                 &gi, sizeof(DISK_GEOMETRY),
  94                                 &gi, sizeof(DISK_GEOMETRY),
  95                                 &retbytes, NULL)) {
  96
  97                 *retblocks = gi.BytesPerSector *
  98                              gi.SectorsPerTrack *
  99                              gi.TracksPerCylinder *
 100                              gi.Cylinders.QuadPart / blocksize;
 101
 102 #ifdef HAVE_GET_FILE_SIZE_EX
 103         } else if (GetFileSizeEx(dev, &filesize)) {
 104                 *retblocks = filesize.QuadPart / blocksize;
 105         }
 106 #else
 107         } else {
 108                 filesize = GetFileSize(dev, NULL);
 109                 if (INVALID_FILE_SIZE != filesize) {
 110                         *retblocks = filesize / blocksize;
 111                 }
 112         }
 113 #endif /* HAVE_GET_FILE_SIZE_EX */
 114
 115         CloseHandle(dev);
 116         return 0;
 117 }
 118
 119 #else
 120
 121 static int valid_offset (int fd, ext2_loff_t offset)
 122 {
 123         char ch;
 124
 125         if (ext2fs_llseek (fd, offset, 0) < 0)
 126                 return 0;
 127         if (read (fd, &ch, 1) < 1)
 128                 return 0;
 129         return 1;
 130 }
 131
 132 /*
 133  * Returns the number of blocks in a partition
 134  */
 135 errcode_t ext2fs_get_device_size(const char *file, int blocksize,
 136                                  blk_t *retblocks)
 137 {
 138         int     fd;
 139         int valid_blkgetsize64 = 1;
 140 #ifdef __linux__
 141         struct          utsname ut;
 142 #endif
 143         unsigned long long size64;
 144         unsigned long   size;
 145         ext2_loff_t high, low;
 146 #ifdef FDGETPRM
 147         struct floppy_struct this_floppy;
 148 #endif
 149 #ifdef HAVE_SYS_DISKLABEL_H
 150         int part;
 151         struct disklabel lab;
 152         struct partition *pp;
 153         char ch;
 154 #endif /* HAVE_SYS_DISKLABEL_H */
 155
 156 #ifdef CONFIG_LFS
 157         fd = open64(file, O_RDONLY);
 158 #else
 159         fd = open(file, O_RDONLY);
 160 #endif
 161         if (fd < 0)
 162                 return errno;
 163
 164 #ifdef DKIOCGETBLOCKCOUNT       /* For Apple Darwin */
 165         if (ioctl(fd, DKIOCGETBLOCKCOUNT, &size64) >= 0) {
 166                 if ((sizeof(*retblocks) < sizeof(unsigned long long))
 167                     && ((size64 / (blocksize / 512)) > 0xFFFFFFFF))
 168                         return EFBIG;
 169                 close(fd);
 170                 *retblocks = size64 / (blocksize / 512);
 171                 return 0;
 172         }
 173 #endif
 174
 175 #ifdef BLKGETSIZE64
 176 #ifdef __linux__
 177         uname(&ut);
 178         if ((ut.release[0] == '2') && (ut.release[1] == '.') &&
 179              (ut.release[2] < '6') && (ut.release[3] == '.'))
 180                 valid_blkgetsize64 = 0;
 181 #endif
 182         if (valid_blkgetsize64 &&
 183             ioctl(fd, BLKGETSIZE64, &size64) >= 0) {
 184                 if ((sizeof(*retblocks) < sizeof(unsigned long long))
 185                     && ((size64 / blocksize) > 0xFFFFFFFF))
 186                         return EFBIG;
 187                 close(fd);
 188                 *retblocks = size64 / blocksize;
 189                 return 0;
 190         }
 191 #endif
 192
 193 #ifdef BLKGETSIZE
 194         if (ioctl(fd, BLKGETSIZE, &size) >= 0) {
 195                 close(fd);
 196                 *retblocks = size / (blocksize / 512);
 197                 return 0;
 198         }
 199 #endif
 200
 201 #ifdef FDGETPRM
 202         if (ioctl(fd, FDGETPRM, &this_floppy) >= 0) {
 203                 close(fd);
 204                 *retblocks = this_floppy.size / (blocksize / 512);
 205                 return 0;
 206         }
 207 #endif
 208
 209 #ifdef HAVE_SYS_DISKLABEL_H
 210 #if defined(DIOCGMEDIASIZE)
 211         {
 212             off_t ms;
 213             u_int bs;
 214             if (ioctl(fd, DIOCGMEDIASIZE, &ms) >= 0) {
 215                 close(fd);
 216                 *retblocks = ms / blocksize;
 217                 return 0;
 218             }
 219         }
 220 #elif defined(DIOCGDINFO)
 221         /* old disklabel interface */
 222         part = strlen(file) - 1;
 223         if (part >= 0) {
 224                 ch = file[part];
 225                 if (isdigit(ch))
 226                         part = 0;
 227                 else if (ch >= 'a' && ch <= 'h')
 228                         part = ch - 'a';
 229                 else
 230                         part = -1;
 231         }
 232         if (part >= 0 && (ioctl(fd, DIOCGDINFO, (char *)&lab) >= 0)) {
 233                 pp = &lab.d_partitions[part];
 234                 if (pp->p_size) {
 235                         close(fd);
 236                         *retblocks = pp->p_size / (blocksize / 512);
 237                         return 0;
 238                 }
 239         }
 240 #endif /* defined(DIOCG*) */
 241 #endif /* HAVE_SYS_DISKLABEL_H */
 242
 243         /*
 244          * OK, we couldn't figure it out by using a specialized ioctl,
 245          * which is generally the best way.  So do binary search to
 246          * find the size of the partition.
 247          */
 248         low = 0;
 249         for (high = 1024; valid_offset (fd, high); high *= 2)
 250                 low = high;
 251         while (low < high - 1)
 252         {
 253                 const ext2_loff_t mid = (low + high) / 2;
 254
 255                 if (valid_offset (fd, mid))
 256                         low = mid;
 257                 else
 258                         high = mid;
 259         }
 260         valid_offset (fd, 0);
 261         close(fd);
 262         size64 = low + 1;
 263         if ((sizeof(*retblocks) < sizeof(unsigned long long))
 264             && ((size64 / blocksize) > 0xFFFFFFFF))
 265                 return EFBIG;
 266         *retblocks = size64 / blocksize;
 267         return 0;
 268 }
 269
 270 #endif /* WIN32 */
 271
 272 #ifdef DEBUG
 273 int main(int argc, char **argv)
 274 {
 275         blk_t   blocks;
 276         int     retval;
 277
 278         if (argc < 2) {
 279                 fprintf(stderr, "Usage: %s device\n", argv[0]);
 280                 exit(1);
 281         }
 282
 283         retval = ext2fs_get_device_size(argv[1], 1024, &blocks);
 284         if (retval) {
 285                 com_err(argv[0], retval,
 286                         "while calling ext2fs_get_device_size");
 287                 exit(1);
 288         }
 289         printf("Device %s has %d 1k blocks.\n", argv[1], blocks);
 290         exit(0);
 291 }
 292 #endif