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 Public
  11  * License.
  12  * %End-Header%
  13  */
  14
  15 #define _LARGEFILE_SOURCE
  16 #define _LARGEFILE64_SOURCE
  17
  18 #include <stdio.h>
  19 #if HAVE_UNISTD_H
  20 #include <unistd.h>
  21 #endif
  22 #if HAVE_ERRNO_H
  23 #include <errno.h>
  24 #endif
  25 #include <fcntl.h>
  26 #ifdef HAVE_SYS_IOCTL_H
  27 #include <sys/ioctl.h>
  28 #endif
  29 #ifdef HAVE_LINUX_FD_H
  30 #include <linux/fd.h>
  31 #endif
  32 #ifdef HAVE_SYS_DISKLABEL_H
  33 #include <sys/disklabel.h>
  34 #endif
  35 #ifdef HAVE_SYS_DISK_H
  36 #ifdef HAVE_SYS_QUEUE_H
  37 #include <sys/queue.h> /* for LIST_HEAD */
  38 #endif
  39 #include <sys/disk.h>
  40 #endif
  41 #ifdef __linux__
  42 #include <sys/utsname.h>
  43 #endif
  44 #if HAVE_SYS_STAT_H
  45 #include <sys/stat.h>
  46 #endif
  47 #include <ctype.h>
  48
  49 #if defined(__linux__) && defined(_IO) && !defined(BLKGETSIZE)
  50 #define BLKGETSIZE _IO(0x12,96) /* return device size */
  51 #endif
  52
  53 #if defined(__linux__) && defined(_IOR) && !defined(BLKGETSIZE64)
  54 #define BLKGETSIZE64 _IOR(0x12,114,size_t)      /* return device size in bytes (u64 *arg) */
  55 #endif
  56
  57 #ifdef APPLE_DARWIN
  58 #define BLKGETSIZE DKIOCGETBLOCKCOUNT32
  59 #endif /* APPLE_DARWIN */
  60
  61 #include "ext2_fs.h"
  62 #include "ext2fs.h"
  63
  64 #if defined(__CYGWIN__) || defined (WIN32)
  65 #include "windows.h"
  66 #include "winioctl.h"
  67
  68 #if (_WIN32_WINNT >= 0x0500)
  69 #define HAVE_GET_FILE_SIZE_EX 1
  70 #endif
  71
  72 errcode_t ext2fs_get_device_size(const char *file, int blocksize,
  73                                  blk_t *retblocks)
  74 {
  75         HANDLE dev;
  76         PARTITION_INFORMATION pi;
  77         DISK_GEOMETRY gi;
  78         DWORD retbytes;
  79 #ifdef HAVE_GET_FILE_SIZE_EX
  80         LARGE_INTEGER filesize;
  81 #else
  82         DWORD filesize;
  83 #endif /* HAVE_GET_FILE_SIZE_EX */
  84
  85         dev = CreateFile(file, GENERIC_READ,
  86                          FILE_SHARE_READ | FILE_SHARE_WRITE ,
  87                          NULL,  OPEN_EXISTING, FILE_ATTRIBUTE_NORMAL,  NULL);
  88
  89         if (dev == INVALID_HANDLE_VALUE)
  90                 return EBADF;
  91         if (DeviceIoControl(dev, IOCTL_DISK_GET_PARTITION_INFO,
  92                             &pi, sizeof(PARTITION_INFORMATION),
  93                             &pi, sizeof(PARTITION_INFORMATION),
  94                             &retbytes, NULL)) {
  95
  96                 *retblocks = pi.PartitionLength.QuadPart / blocksize;
  97
  98         } else if (DeviceIoControl(dev, IOCTL_DISK_GET_DRIVE_GEOMETRY,
  99                                 &gi, sizeof(DISK_GEOMETRY),
 100                                 &gi, sizeof(DISK_GEOMETRY),
 101                                 &retbytes, NULL)) {
 102
 103                 *retblocks = gi.BytesPerSector *
 104                              gi.SectorsPerTrack *
 105                              gi.TracksPerCylinder *
 106                              gi.Cylinders.QuadPart / blocksize;
 107
 108 #ifdef HAVE_GET_FILE_SIZE_EX
 109         } else if (GetFileSizeEx(dev, &filesize)) {
 110                 *retblocks = filesize.QuadPart / blocksize;
 111         }
 112 #else
 113         } else {
 114                 filesize = GetFileSize(dev, NULL);
 115                 if (INVALID_FILE_SIZE != filesize) {
 116                         *retblocks = filesize / blocksize;
 117                 }
 118         }
 119 #endif /* HAVE_GET_FILE_SIZE_EX */
 120
 121         CloseHandle(dev);
 122         return 0;
 123 }
 124
 125 #else
 126
 127 static int valid_offset (int fd, ext2_loff_t offset)
 128 {
 129         char ch;
 130
 131         if (ext2fs_llseek (fd, offset, 0) < 0)
 132                 return 0;
 133         if (read (fd, &ch, 1) < 1)
 134                 return 0;
 135         return 1;
 136 }
 137
 138 /*
 139  * Returns the number of blocks in a partition
 140  */
 141 errcode_t ext2fs_get_device_size(const char *file, int blocksize,
 142                                  blk_t *retblocks)
 143 {
 144         int     fd, rc = 0;
 145         int valid_blkgetsize64 = 1;
 146 #ifdef __linux__
 147         struct          utsname ut;
 148 #endif
 149         unsigned long long size64;
 150         unsigned long   size;
 151         ext2_loff_t high, low;
 152 #ifdef FDGETPRM
 153         struct floppy_struct this_floppy;
 154 #endif
 155 #ifdef HAVE_SYS_DISKLABEL_H
 156         int part;
 157         struct disklabel lab;
 158         struct partition *pp;
 159         char ch;
 160 #endif /* HAVE_SYS_DISKLABEL_H */
 161
 162 #ifdef HAVE_OPEN64
 163         fd = open64(file, O_RDONLY);
 164 #else
 165         fd = open(file, O_RDONLY);
 166 #endif
 167         if (fd < 0)
 168                 return errno;
 169
 170 #ifdef DKIOCGETBLOCKCOUNT       /* For Apple Darwin */
 171         if (ioctl(fd, DKIOCGETBLOCKCOUNT, &size64) >= 0) {
 172                 if ((sizeof(*retblocks) < sizeof(unsigned long long))
 173                     && ((size64 / (blocksize / 512)) > 0xFFFFFFFF)) {
 174                         rc = EFBIG;
 175                         goto out;
 176                 }
 177                 *retblocks = size64 / (blocksize / 512);
 178                 goto out;
 179         }
 180 #endif
 181
 182 #ifdef BLKGETSIZE64
 183 #ifdef __linux__
 184         if ((uname(&ut) == 0) &&
 185             ((ut.release[0] == '2') && (ut.release[1] == '.') &&
 186              (ut.release[2] < '6') && (ut.release[3] == '.')))
 187                 valid_blkgetsize64 = 0;
 188 #endif
 189         if (valid_blkgetsize64 &&
 190             ioctl(fd, BLKGETSIZE64, &size64) >= 0) {
 191                 if ((sizeof(*retblocks) < sizeof(unsigned long long)) &&
 192                     ((size64 / blocksize) > 0xFFFFFFFF)) {
 193                         rc = EFBIG;
 194                         goto out;
 195                 }
 196                 *retblocks = size64 / blocksize;
 197                 goto out;
 198         }
 199 #endif
 200
 201 #ifdef BLKGETSIZE
 202         if (ioctl(fd, BLKGETSIZE, &size) >= 0) {
 203                 *retblocks = size / (blocksize / 512);
 204                 goto out;
 205         }
 206 #endif
 207
 208 #ifdef FDGETPRM
 209         if (ioctl(fd, FDGETPRM, &this_floppy) >= 0) {
 210                 *retblocks = this_floppy.size / (blocksize / 512);
 211                 goto out;
 212         }
 213 #endif
 214
 215 #ifdef HAVE_SYS_DISKLABEL_H
 216 #if defined(DIOCGMEDIASIZE)
 217         {
 218             off_t ms;
 219             u_int bs;
 220             if (ioctl(fd, DIOCGMEDIASIZE, &ms) >= 0) {
 221                 *retblocks = ms / blocksize;
 222                 goto out;
 223             }
 224         }
 225 #elif defined(DIOCGDINFO)
 226         /* old disklabel interface */
 227         part = strlen(file) - 1;
 228         if (part >= 0) {
 229                 ch = file[part];
 230                 if (isdigit(ch))
 231                         part = 0;
 232                 else if (ch >= 'a' && ch <= 'h')
 233                         part = ch - 'a';
 234                 else
 235                         part = -1;
 236         }
 237         if (part >= 0 && (ioctl(fd, DIOCGDINFO, (char *)&lab) >= 0)) {
 238                 pp = &lab.d_partitions[part];
 239                 if (pp->p_size) {
 240                         *retblocks = pp->p_size / (blocksize / 512);
 241                         goto out;
 242                 }
 243         }
 244 #endif /* defined(DIOCG*) */
 245 #endif /* HAVE_SYS_DISKLABEL_H */
 246
 247         {
 248 #ifdef HAVE_FSTAT64
 249                 struct stat64   st;
 250                 if (fstat64(fd, &st) == 0)
 251 #else
 252                 struct stat     st;
 253                 if (fstat(fd, &st) == 0)
 254 #endif
 255                         if (S_ISREG(st.st_mode)) {
 256                                 if ((sizeof(*retblocks) < sizeof(unsigned long long)) &&
 257                                     ((st.st_size / blocksize) > 0xFFFFFFFF)) {
 258                                         rc = EFBIG;
 259                                         goto out;
 260                                 }
 261                                 *retblocks = st.st_size / blocksize;
 262                                 goto out;
 263                         }
 264         }
 265
 266         /*
 267          * OK, we couldn't figure it out by using a specialized ioctl,
 268          * which is generally the best way.  So do binary search to
 269          * find the size of the partition.
 270          */
 271         low = 0;
 272         for (high = 1024; valid_offset (fd, high); high *= 2)
 273                 low = high;
 274         while (low < high - 1)
 275         {
 276                 const ext2_loff_t mid = (low + high) / 2;
 277
 278                 if (valid_offset (fd, mid))
 279                         low = mid;
 280                 else
 281                         high = mid;
 282         }
 283         valid_offset (fd, 0);
 284         size64 = low + 1;
 285         if ((sizeof(*retblocks) < sizeof(unsigned long long))
 286             && ((size64 / blocksize) > 0xFFFFFFFF)) {
 287                 rc = EFBIG;
 288                 goto out;
 289         }
 290         *retblocks = size64 / blocksize;
 291 out:
 292         close(fd);
 293         return rc;
 294 }
 295
 296 #endif /* WIN32 */
 297
 298 #ifdef DEBUG
 299 int main(int argc, char **argv)
 300 {
 301         blk_t   blocks;
 302         int     retval;
 303
 304         if (argc < 2) {
 305                 fprintf(stderr, "Usage: %s device\n", argv[0]);
 306                 exit(1);
 307         }
 308
 309         retval = ext2fs_get_device_size(argv[1], 1024, &blocks);
 310         if (retval) {
 311                 com_err(argv[0], retval,
 312                         "while calling ext2fs_get_device_size");
 313                 exit(1);
 314         }
 315         printf("Device %s has %u 1k blocks.\n", argv[1], blocks);
 316         exit(0);
 317 }
 318 #endif