3 exFAT file system implementation library.
5 Copyright (C) 2010-2012 Andrew Nayenko
7 This program is free software: you can redistribute it and/or modify
8 it under the terms of the GNU General Public License as published by
9 the Free Software Foundation, either version 3 of the License, or
10 (at your option) any later version.
12 This program is distributed in the hope that it will be useful,
13 but WITHOUT ANY WARRANTY; without even the implied warranty of
14 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
15 GNU General Public License for more details.
17 You should have received a copy of the GNU General Public License
18 along with this program. If not, see <http://www.gnu.org/licenses/>.
23 #include <sys/types.h>
34 #if !defined(_FILE_OFFSET_BITS) || (_FILE_OFFSET_BITS != 64)
35 #error You should define _FILE_OFFSET_BITS=64
44 ublio_filehandle_t ufh;
48 struct exfat_dev* exfat_open(const char* spec, enum exfat_mode mode)
50 struct exfat_dev* dev;
53 struct ublio_param up;
56 dev = malloc(sizeof(struct exfat_dev));
59 exfat_error("failed to allocate memory for device structure");
66 dev->fd = open(spec, O_RDONLY);
70 exfat_error("failed to open `%s' in read-only mode", spec);
73 dev->mode = EXFAT_MODE_RO;
76 dev->fd = open(spec, O_RDWR);
80 exfat_error("failed to open `%s' in read-write mode", spec);
83 dev->mode = EXFAT_MODE_RW;
86 dev->fd = open(spec, O_RDWR);
89 dev->mode = EXFAT_MODE_RW;
92 dev->fd = open(spec, O_RDONLY);
95 dev->mode = EXFAT_MODE_RO;
96 exfat_warn("`%s' is write-protected, mounting read-only", spec);
100 exfat_error("failed to open `%s'", spec);
104 if (fstat(dev->fd, &stbuf) != 0)
108 exfat_error("failed to fstat `%s'", spec);
111 if (!S_ISBLK(stbuf.st_mode) &&
112 !S_ISCHR(stbuf.st_mode) &&
113 !S_ISREG(stbuf.st_mode))
117 exfat_error("`%s' is neither a device, nor a regular file", spec);
122 memset(&up, 0, sizeof(struct ublio_param));
123 up.up_blocksize = 256 * 1024;
126 up.up_priv = &dev->fd;
129 dev->ufh = ublio_open(&up);
130 if (dev->ufh == NULL)
134 exfat_error("failed to initialize ublio");
142 int exfat_close(struct exfat_dev* dev)
145 if (ublio_close(dev->ufh) != 0)
146 exfat_error("failed to close ublio");
148 if (close(dev->fd) != 0)
151 exfat_error("failed to close device");
158 int exfat_fsync(struct exfat_dev* dev)
161 if (ublio_fsync(dev->ufh) != 0)
163 if (fsync(dev->fd) != 0)
166 exfat_error("fsync failed");
172 enum exfat_mode exfat_mode(const struct exfat_dev* dev)
177 off_t exfat_seek(struct exfat_dev* dev, off_t offset, int whence)
180 /* XXX SEEK_CUR will be handled incorrectly */
181 return dev->pos = lseek(dev->fd, offset, whence);
183 return lseek(dev->fd, offset, whence);
187 ssize_t exfat_read(struct exfat_dev* dev, void* buffer, size_t size)
190 ssize_t result = ublio_pread(dev->ufh, buffer, size, dev->pos);
195 return read(dev->fd, buffer, size);
199 ssize_t exfat_write(struct exfat_dev* dev, const void* buffer, size_t size)
202 ssize_t result = ublio_pwrite(dev->ufh, buffer, size, dev->pos);
207 return write(dev->fd, buffer, size);
211 void exfat_pread(struct exfat_dev* dev, void* buffer, size_t size,
215 if (ublio_pread(dev->ufh, buffer, size, offset) != size)
217 if (pread(dev->fd, buffer, size, offset) != size)
219 exfat_bug("failed to read %zu bytes from file at %"PRIu64, size,
223 void exfat_pwrite(struct exfat_dev* dev, const void* buffer, size_t size,
227 if (ublio_pwrite(dev->ufh, buffer, size, offset) != size)
229 if (pwrite(dev->fd, buffer, size, offset) != size)
231 exfat_bug("failed to write %zu bytes to file at %"PRIu64, size,
235 ssize_t exfat_generic_pread(const struct exfat* ef, struct exfat_node* node,
236 void* buffer, size_t size, off_t offset)
240 off_t lsize, loffset, remainder;
242 if (offset >= node->size)
247 cluster = exfat_advance_cluster(ef, node, offset / CLUSTER_SIZE(*ef->sb));
248 if (CLUSTER_INVALID(cluster))
250 exfat_error("invalid cluster 0x%x while reading", cluster);
254 loffset = offset % CLUSTER_SIZE(*ef->sb);
255 remainder = MIN(size, node->size - offset);
256 while (remainder > 0)
258 if (CLUSTER_INVALID(cluster))
260 exfat_error("invalid cluster 0x%x while reading", cluster);
263 lsize = MIN(CLUSTER_SIZE(*ef->sb) - loffset, remainder);
264 exfat_pread(ef->dev, bufp, lsize, exfat_c2o(ef, cluster) + loffset);
268 cluster = exfat_next_cluster(ef, node, cluster);
270 if (!ef->ro && !ef->noatime)
271 exfat_update_atime(node);
272 return size - remainder;
275 ssize_t exfat_generic_pwrite(struct exfat* ef, struct exfat_node* node,
276 const void* buffer, size_t size, off_t offset)
279 const char* bufp = buffer;
280 off_t lsize, loffset, remainder;
282 if (offset + size > node->size)
284 int rc = exfat_truncate(ef, node, offset + size);
291 cluster = exfat_advance_cluster(ef, node, offset / CLUSTER_SIZE(*ef->sb));
292 if (CLUSTER_INVALID(cluster))
294 exfat_error("invalid cluster 0x%x while writing", cluster);
298 loffset = offset % CLUSTER_SIZE(*ef->sb);
300 while (remainder > 0)
302 if (CLUSTER_INVALID(cluster))
304 exfat_error("invalid cluster 0x%x while writing", cluster);
307 lsize = MIN(CLUSTER_SIZE(*ef->sb) - loffset, remainder);
308 exfat_pwrite(ef->dev, bufp, lsize, exfat_c2o(ef, cluster) + loffset);
312 cluster = exfat_next_cluster(ef, node, cluster);
314 exfat_update_mtime(node);
315 return size - remainder;