3 exFAT file system implementation library.
5 Free exFAT implementation.
6 Copyright (C) 2010-2013 Andrew Nayenko
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.
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.
18 You should have received a copy of the GNU General Public License along
19 with this program; if not, write to the Free Software Foundation, Inc.,
20 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
25 #include <sys/types.h>
31 #if defined(__APPLE__)
33 #elif defined(__OpenBSD__)
34 #include <sys/param.h>
35 #include <sys/disklabel.h>
37 #include <sys/ioctl.h>
39 #include <sys/mount.h>
49 off_t size; /* in bytes */
52 ublio_filehandle_t ufh;
56 static int open_ro(const char* spec)
58 return open(spec, O_RDONLY);
61 static int open_rw(const char* spec)
63 int fd = open(spec, O_RDWR);
68 This code is needed because after "blockdev --setro" kernel still
69 allows to open the device in read-write mode but fails writes.
73 if (ioctl(fd, BLKROGET, &ro) != 0)
88 struct exfat_dev* exfat_open(const char* spec, enum exfat_mode mode)
90 struct exfat_dev* dev;
93 struct ublio_param up;
96 dev = malloc(sizeof(struct exfat_dev));
99 exfat_error("failed to allocate memory for device structure");
106 dev->fd = open_ro(spec);
110 exfat_error("failed to open `%s' in read-only mode", spec);
113 dev->mode = EXFAT_MODE_RO;
116 dev->fd = open_rw(spec);
120 exfat_error("failed to open `%s' in read-write mode", spec);
123 dev->mode = EXFAT_MODE_RW;
126 dev->fd = open_rw(spec);
129 dev->mode = EXFAT_MODE_RW;
132 dev->fd = open_ro(spec);
135 dev->mode = EXFAT_MODE_RO;
136 exfat_warn("`%s' is write-protected, mounting read-only", spec);
140 exfat_error("failed to open `%s'", spec);
144 if (fstat(dev->fd, &stbuf) != 0)
148 exfat_error("failed to fstat `%s'", spec);
151 if (!S_ISBLK(stbuf.st_mode) &&
152 !S_ISCHR(stbuf.st_mode) &&
153 !S_ISREG(stbuf.st_mode))
157 exfat_error("`%s' is neither a device, nor a regular file", spec);
161 #if defined(__APPLE__)
162 if (!S_ISREG(stbuf.st_mode))
164 uint32_t block_size = 0;
167 if (ioctl(dev->fd, DKIOCGETBLOCKSIZE, &block_size) != 0)
171 exfat_error("failed to get block size");
174 if (ioctl(dev->fd, DKIOCGETBLOCKCOUNT, &blocks) != 0)
178 exfat_error("failed to get blocks count");
181 dev->size = blocks * block_size;
184 #elif defined(__OpenBSD__)
185 if (!S_ISREG(stbuf.st_mode))
187 struct disklabel lab;
188 struct partition* pp;
191 if (ioctl(dev->fd, DIOCGDINFO, &lab) == -1)
195 exfat_error("failed to get disklabel");
199 /* Don't need to check that partition letter is valid as we won't get
200 this far otherwise. */
201 partition = strchr(spec, '\0') - 1;
202 pp = &(lab.d_partitions[*partition - 'a']);
203 dev->size = DL_GETPSIZE(pp) * lab.d_secsize;
205 if (pp->p_fstype != FS_NTFS)
206 exfat_warn("partition type is not 0x07 (NTFS/exFAT); "
207 "you can fix this with fdisk(8)");
212 /* works for Linux, FreeBSD, Solaris */
213 dev->size = exfat_seek(dev, 0, SEEK_END);
218 exfat_error("failed to get size of `%s'", spec);
221 if (exfat_seek(dev, 0, SEEK_SET) == -1)
225 exfat_error("failed to seek to the beginning of `%s'", spec);
231 memset(&up, 0, sizeof(struct ublio_param));
232 up.up_blocksize = 256 * 1024;
235 up.up_priv = &dev->fd;
238 dev->ufh = ublio_open(&up);
239 if (dev->ufh == NULL)
243 exfat_error("failed to initialize ublio");
251 int exfat_close(struct exfat_dev* dev)
256 if (ublio_close(dev->ufh) != 0)
258 exfat_error("failed to close ublio");
262 if (close(dev->fd) != 0)
264 exfat_error("failed to close device");
271 int exfat_fsync(struct exfat_dev* dev)
276 if (ublio_fsync(dev->ufh) != 0)
278 exfat_error("ublio fsync failed");
282 if (fsync(dev->fd) != 0)
284 exfat_error("fsync failed");
290 enum exfat_mode exfat_get_mode(const struct exfat_dev* dev)
295 off_t exfat_get_size(const struct exfat_dev* dev)
300 off_t exfat_seek(struct exfat_dev* dev, off_t offset, int whence)
303 /* XXX SEEK_CUR will be handled incorrectly */
304 return dev->pos = lseek(dev->fd, offset, whence);
306 return lseek(dev->fd, offset, whence);
310 ssize_t exfat_read(struct exfat_dev* dev, void* buffer, size_t size)
313 ssize_t result = ublio_pread(dev->ufh, buffer, size, dev->pos);
318 return read(dev->fd, buffer, size);
322 ssize_t exfat_write(struct exfat_dev* dev, const void* buffer, size_t size)
325 ssize_t result = ublio_pwrite(dev->ufh, buffer, size, dev->pos);
330 return write(dev->fd, buffer, size);
334 ssize_t exfat_pread(struct exfat_dev* dev, void* buffer, size_t size,
338 return ublio_pread(dev->ufh, buffer, size, offset);
340 return pread(dev->fd, buffer, size, offset);
344 ssize_t exfat_pwrite(struct exfat_dev* dev, const void* buffer, size_t size,
348 return ublio_pwrite(dev->ufh, buffer, size, offset);
350 return pwrite(dev->fd, buffer, size, offset);
354 ssize_t exfat_generic_pread(const struct exfat* ef, struct exfat_node* node,
355 void* buffer, size_t size, off_t offset)
359 off_t lsize, loffset, remainder;
361 if (offset >= node->size)
366 cluster = exfat_advance_cluster(ef, node, offset / CLUSTER_SIZE(*ef->sb));
367 if (CLUSTER_INVALID(cluster))
369 exfat_error("invalid cluster 0x%x while reading", cluster);
373 loffset = offset % CLUSTER_SIZE(*ef->sb);
374 remainder = MIN(size, node->size - offset);
375 while (remainder > 0)
377 if (CLUSTER_INVALID(cluster))
379 exfat_error("invalid cluster 0x%x while reading", cluster);
382 lsize = MIN(CLUSTER_SIZE(*ef->sb) - loffset, remainder);
383 if (exfat_pread(ef->dev, bufp, lsize,
384 exfat_c2o(ef, cluster) + loffset) < 0)
386 exfat_error("failed to read cluster %#x", cluster);
392 cluster = exfat_next_cluster(ef, node, cluster);
394 if (!ef->ro && !ef->noatime)
395 exfat_update_atime(node);
396 return MIN(size, node->size - offset) - remainder;
399 ssize_t exfat_generic_pwrite(struct exfat* ef, struct exfat_node* node,
400 const void* buffer, size_t size, off_t offset)
403 const char* bufp = buffer;
404 off_t lsize, loffset, remainder;
406 if (offset > node->size)
407 if (exfat_truncate(ef, node, offset, true) != 0)
409 if (offset + size > node->size)
410 if (exfat_truncate(ef, node, offset + size, false) != 0)
415 cluster = exfat_advance_cluster(ef, node, offset / CLUSTER_SIZE(*ef->sb));
416 if (CLUSTER_INVALID(cluster))
418 exfat_error("invalid cluster 0x%x while writing", cluster);
422 loffset = offset % CLUSTER_SIZE(*ef->sb);
424 while (remainder > 0)
426 if (CLUSTER_INVALID(cluster))
428 exfat_error("invalid cluster 0x%x while writing", cluster);
431 lsize = MIN(CLUSTER_SIZE(*ef->sb) - loffset, remainder);
432 if (exfat_pwrite(ef->dev, bufp, lsize,
433 exfat_c2o(ef, cluster) + loffset) < 0)
435 exfat_error("failed to write cluster %#x", cluster);
441 cluster = exfat_next_cluster(ef, node, cluster);
443 exfat_update_mtime(node);
444 return size - remainder;