lib/ext2fs/getsize.c

   1 /*
   2  * getsize.c --- get the size of a partition.
   3  *
   4  * Copyright (C) 1995, 1995 Theodore Ts'o.
   5  * Copyright (C) 2003 VMware, Inc.
   6  *
   7  * Windows version of ext2fs_get_device_size by Chris Li, VMware.
   8  *
   9  * %Begin-Header%
  10  * This file may be redistributed under the terms of the GNU Library
  11  * General Public License, version 2.
  12  * %End-Header%
  13  */
  14
  15 #ifndef _LARGEFILE_SOURCE
  16 #define _LARGEFILE_SOURCE
  17 #endif
  18 #ifndef _LARGEFILE64_SOURCE
  19 #define _LARGEFILE64_SOURCE
  20 #endif
  21
  22 #include "config.h"
  23 #include <stdio.h>
  24 #if HAVE_UNISTD_H
  25 #include <unistd.h>
  26 #endif
  27 #if HAVE_ERRNO_H
  28 #include <errno.h>
  29 #endif
  30 #include <fcntl.h>
  31 #ifdef HAVE_SYS_IOCTL_H
  32 #include <sys/ioctl.h>
  33 #endif
  34 #ifdef HAVE_LINUX_FD_H
  35 #include <linux/fd.h>
  36 #endif
  37 #ifdef HAVE_SYS_DISKLABEL_H
  38 #include <sys/disklabel.h>
  39 #endif
  40 #ifdef HAVE_SYS_DISK_H
  41 #include <sys/disk.h>
  42 #endif
  43 #ifdef __linux__
  44 #include <sys/utsname.h>
  45 #endif
  46 #if HAVE_SYS_STAT_H
  47 #include <sys/stat.h>
  48 #endif
  49 #include <ctype.h>
  50
  51 #if defined(__linux__) && defined(_IO) && !defined(BLKGETSIZE)
  52 #define BLKGETSIZE _IO(0x12,96) /* return device size */
  53 #endif
  54
  55 #if defined(__linux__) && defined(_IOR) && !defined(BLKGETSIZE64)
  56 #define BLKGETSIZE64 _IOR(0x12,114,size_t)      /* return device size in bytes (u64 *arg) */
  57 #endif
  58
  59 #ifdef APPLE_DARWIN
  60 #define BLKGETSIZE DKIOCGETBLOCKCOUNT32
  61 #endif /* APPLE_DARWIN */
  62
  63 #include "ext2_fs.h"
  64 #include "ext2fs.h"
  65
  66 #if defined(__CYGWIN__) || defined (WIN32)
  67 #include "windows.h"
  68 #include "winioctl.h"
  69
  70 #if (_WIN32_WINNT >= 0x0500)
  71 #define HAVE_GET_FILE_SIZE_EX 1
  72 #endif
  73
  74 HANDLE windows_get_handle(io_channel channel);
  75
  76 errcode_t ext2fs_get_device_size2(const char *file, int blocksize,
  77                                   blk64_t *retblocks)
  78 {
  79         HANDLE dev;
  80         PARTITION_INFORMATION pi;
  81         DISK_GEOMETRY gi;
  82         DWORD retbytes;
  83 #ifdef HAVE_GET_FILE_SIZE_EX
  84         LARGE_INTEGER filesize;
  85 #else
  86         DWORD filesize;
  87 #endif /* HAVE_GET_FILE_SIZE_EX */
  88
  89         io_channel data_io = 0;
  90         int retval;
  91
  92         retval = windows_io_manager->open(file, 0, &data_io);
  93         if (retval)
  94                 return retval;
  95
  96         dev = windows_get_handle(data_io);
  97         if (dev == INVALID_HANDLE_VALUE)
  98                 return EBADF;
  99
 100         if (DeviceIoControl(dev, IOCTL_DISK_GET_PARTITION_INFO,
 101                             &pi, sizeof(PARTITION_INFORMATION),
 102                             &pi, sizeof(PARTITION_INFORMATION),
 103                             &retbytes, NULL)) {
 104
 105                 *retblocks = pi.PartitionLength.QuadPart / blocksize;
 106
 107         } else if (DeviceIoControl(dev, IOCTL_DISK_GET_DRIVE_GEOMETRY,
 108                                 &gi, sizeof(DISK_GEOMETRY),
 109                                 &gi, sizeof(DISK_GEOMETRY),
 110                                 &retbytes, NULL)) {
 111
 112                 *retblocks = gi.BytesPerSector *
 113                              gi.SectorsPerTrack *
 114                              gi.TracksPerCylinder *
 115                              gi.Cylinders.QuadPart / blocksize;
 116
 117 #ifdef HAVE_GET_FILE_SIZE_EX
 118         } else if (GetFileSizeEx(dev, &filesize)) {
 119                 *retblocks = filesize.QuadPart / blocksize;
 120         }
 121 #else
 122         } else {
 123                 filesize = GetFileSize(dev, NULL);
 124                 if (INVALID_FILE_SIZE != filesize) {
 125                         *retblocks = filesize / blocksize;
 126                 }
 127         }
 128 #endif /* HAVE_GET_FILE_SIZE_EX */
 129
 130         windows_io_manager->close(data_io);
 131
 132         return 0;
 133 }
 134
 135 #else
 136
 137 static int valid_offset (int fd, ext2_loff_t offset)
 138 {
 139         char ch;
 140
 141         if (ext2fs_llseek (fd, offset, 0) < 0)
 142                 return 0;
 143         if (read (fd, &ch, 1) < 1)
 144                 return 0;
 145         return 1;
 146 }
 147
 148 /*
 149  * Returns the number of blocks in a partition
 150  */
 151 errcode_t ext2fs_get_device_size2(const char *file, int blocksize,
 152                                   blk64_t *retblocks)
 153 {
 154         int     fd, rc = 0;
 155         unsigned long long size64;
 156         ext2_loff_t high, low;
 157
 158         fd = ext2fs_open_file(file, O_RDONLY, 0);
 159         if (fd < 0)
 160                 return errno;
 161
 162 #if defined DKIOCGETBLOCKCOUNT && defined DKIOCGETBLOCKSIZE     /* For Apple Darwin */
 163         unsigned int size;
 164
 165         if (ioctl(fd, DKIOCGETBLOCKCOUNT, &size64) >= 0 &&
 166             ioctl(fd, DKIOCGETBLOCKSIZE, &size) >= 0) {
 167                 *retblocks = size64 * size / blocksize;
 168                 goto out;
 169         }
 170 #endif
 171
 172 #ifdef BLKGETSIZE64
 173         {
 174                 int valid_blkgetsize64 = 1;
 175 #ifdef __linux__
 176                 struct utsname ut;
 177
 178                 if ((uname(&ut) == 0) &&
 179                     ((ut.release[0] == '2') && (ut.release[1] == '.') &&
 180                      (ut.release[2] < '6') && (ut.release[3] == '.')))
 181                         valid_blkgetsize64 = 0;
 182 #endif
 183                 if (valid_blkgetsize64 &&
 184                     ioctl(fd, BLKGETSIZE64, &size64) >= 0) {
 185                         *retblocks = size64 / blocksize;
 186                         goto out;
 187                 }
 188         }
 189 #endif /* BLKGETSIZE64 */
 190
 191 #ifdef BLKGETSIZE
 192         {
 193                 unsigned long   size;
 194
 195                 if (ioctl(fd, BLKGETSIZE, &size) >= 0) {
 196                         *retblocks = size / (blocksize / 512);
 197                         goto out;
 198                 }
 199         }
 200 #endif
 201
 202 #ifdef FDGETPRM
 203         {
 204                 struct floppy_struct this_floppy;
 205
 206                 if (ioctl(fd, FDGETPRM, &this_floppy) >= 0) {
 207                         *retblocks = this_floppy.size / (blocksize / 512);
 208                         goto out;
 209                 }
 210         }
 211 #endif
 212
 213 #ifdef HAVE_SYS_DISKLABEL_H
 214         {
 215                 int part;
 216                 struct disklabel lab;
 217                 struct partition *pp;
 218                 char ch;
 219
 220 #if defined(DIOCGMEDIASIZE)
 221                 {
 222                         off_t ms;
 223                         u_int bs;
 224                         if (ioctl(fd, DIOCGMEDIASIZE, &ms) >= 0) {
 225                                 *retblocks = ms / blocksize;
 226                                 goto out;
 227                         }
 228                 }
 229 #elif defined(DIOCGDINFO)
 230                 /* old disklabel interface */
 231                 part = strlen(file) - 1;
 232                 if (part >= 0) {
 233                         ch = file[part];
 234                         if (isdigit(ch))
 235                                 part = 0;
 236                         else if (ch >= 'a' && ch <= 'h')
 237                                 part = ch - 'a';
 238                         else
 239                                 part = -1;
 240                 }
 241                 if (part >= 0 && (ioctl(fd, DIOCGDINFO, (char *)&lab) >= 0)) {
 242                         pp = &lab.d_partitions[part];
 243                         if (pp->p_size) {
 244                                 *retblocks = pp->p_size / (blocksize / 512);
 245                                 goto out;
 246                         }
 247                 }
 248 #endif /* defined(DIOCG*) */
 249         }
 250 #endif /* HAVE_SYS_DISKLABEL_H */
 251
 252         {
 253                 ext2fs_struct_stat st;
 254
 255                 if (ext2fs_fstat(fd, &st) == 0)
 256                         if (S_ISREG(st.st_mode)) {
 257                                 *retblocks = st.st_size / blocksize;
 258                                 goto out;
 259                         }
 260         }
 261
 262         /*
 263          * OK, we couldn't figure it out by using a specialized ioctl,
 264          * which is generally the best way.  So do binary search to
 265          * find the size of the partition.
 266          */
 267         low = 0;
 268         for (high = 1024; valid_offset(fd, high); high *= 2)
 269                 low = high;
 270         while (low < high - 1) {
 271                 const ext2_loff_t mid = (low + high) / 2;
 272
 273                 if (valid_offset (fd, mid))
 274                         low = mid;
 275                 else
 276                         high = mid;
 277         }
 278         valid_offset(fd, 0);
 279         size64 = low + 1;
 280         *retblocks = size64 / blocksize;
 281 out:
 282         close(fd);
 283         return rc;
 284 }
 285
 286 #endif /* WIN32 */
 287
 288 errcode_t ext2fs_get_device_size(const char *file, int blocksize,
 289                                  blk_t *retblocks)
 290 {
 291         errcode_t retval;
 292         blk64_t blocks;
 293
 294         retval = ext2fs_get_device_size2(file, blocksize, &blocks);
 295         if (retval)
 296                 return retval;
 297         if (blocks >= (1ULL << 32))
 298                 return EFBIG;
 299         *retblocks = (blk_t) blocks;
 300         return 0;
 301 }
 302
 303 #ifdef DEBUG
 304 int main(int argc, char **argv)
 305 {
 306         blk_t   blocks;
 307         int     retval;
 308
 309         if (argc < 2) {
 310                 fprintf(stderr, "Usage: %s device\n", argv[0]);
 311                 exit(1);
 312         }
 313
 314         retval = ext2fs_get_device_size(argv[1], 1024, &blocks);
 315         if (retval) {
 316                 com_err(argv[0], retval,
 317                         "while calling ext2fs_get_device_size");
 318                 exit(1);
 319         }
 320         printf("Device %s has %u 1k blocks.\n", argv[1], blocks);
 321         exit(0);
 322 }
 323 #endif