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-rw-r--r--exfat/libexfat/io.c385
1 files changed, 385 insertions, 0 deletions
diff --git a/exfat/libexfat/io.c b/exfat/libexfat/io.c
new file mode 100644
index 000000000..65df63a78
--- /dev/null
+++ b/exfat/libexfat/io.c
@@ -0,0 +1,385 @@
+/*
+ io.c (02.09.09)
+ exFAT file system implementation library.
+
+ Copyright (C) 2010-2012 Andrew Nayenko
+
+ This program is free software: you can redistribute it and/or modify
+ it under the terms of the GNU General Public License as published by
+ the Free Software Foundation, either version 3 of the License, or
+ (at your option) any later version.
+
+ This program is distributed in the hope that it will be useful,
+ but WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ GNU General Public License for more details.
+
+ You should have received a copy of the GNU General Public License
+ along with this program. If not, see <http://www.gnu.org/licenses/>.
+*/
+
+#include "exfat.h"
+#include <inttypes.h>
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <sys/mount.h>
+#include <fcntl.h>
+#include <unistd.h>
+#include <string.h>
+#ifdef __APPLE__
+#include <sys/disk.h>
+#endif
+#ifdef USE_UBLIO
+#include <sys/uio.h>
+#include <ublio.h>
+#endif
+
+struct exfat_dev
+{
+ int fd;
+ enum exfat_mode mode;
+ off64_t size; /* in bytes */
+#ifdef USE_UBLIO
+ off64_t pos;
+ ublio_filehandle_t ufh;
+#endif
+};
+
+static int open_ro(const char* spec)
+{
+ return open(spec, O_RDONLY);
+}
+
+static int open_rw(const char* spec)
+{
+ int fd = open(spec, O_RDWR);
+#ifdef __linux__
+ int ro = 0;
+
+ /*
+ This ioctl is needed because after "blockdev --setro" kernel still
+ allows to open the device in read-write mode but fails writes.
+ */
+ if (fd != -1 && ioctl(fd, BLKROGET, &ro) == 0 && ro)
+ {
+ close(fd);
+ return -1;
+ }
+#endif
+ return fd;
+}
+
+struct exfat_dev* exfat_open(const char* spec, enum exfat_mode mode)
+{
+ struct exfat_dev* dev;
+ struct stat stbuf;
+#ifdef USE_UBLIO
+ struct ublio_param up;
+#endif
+
+ dev = malloc(sizeof(struct exfat_dev));
+ if (dev == NULL)
+ {
+ exfat_error("failed to allocate memory for device structure");
+ return NULL;
+ }
+
+ switch (mode)
+ {
+ case EXFAT_MODE_RO:
+ dev->fd = open_ro(spec);
+ if (dev->fd == -1)
+ {
+ free(dev);
+ exfat_error("failed to open `%s' in read-only mode", spec);
+ return NULL;
+ }
+ dev->mode = EXFAT_MODE_RO;
+ break;
+ case EXFAT_MODE_RW:
+ dev->fd = open_rw(spec);
+ if (dev->fd == -1)
+ {
+ free(dev);
+ exfat_error("failed to open `%s' in read-write mode", spec);
+ return NULL;
+ }
+ dev->mode = EXFAT_MODE_RW;
+ break;
+ case EXFAT_MODE_ANY:
+ dev->fd = open_rw(spec);
+ if (dev->fd != -1)
+ {
+ dev->mode = EXFAT_MODE_RW;
+ break;
+ }
+ dev->fd = open_ro(spec);
+ if (dev->fd != -1)
+ {
+ dev->mode = EXFAT_MODE_RO;
+ exfat_warn("`%s' is write-protected, mounting read-only", spec);
+ break;
+ }
+ free(dev);
+ exfat_error("failed to open `%s'", spec);
+ return NULL;
+ }
+
+ if (fstat(dev->fd, &stbuf) != 0)
+ {
+ close(dev->fd);
+ free(dev);
+ exfat_error("failed to fstat `%s'", spec);
+ return NULL;
+ }
+ if (!S_ISBLK(stbuf.st_mode) &&
+ !S_ISCHR(stbuf.st_mode) &&
+ !S_ISREG(stbuf.st_mode))
+ {
+ close(dev->fd);
+ free(dev);
+ exfat_error("`%s' is neither a device, nor a regular file", spec);
+ return NULL;
+ }
+
+#ifdef __APPLE__
+ if (!S_ISREG(stbuf.st_mode))
+ {
+ uint32_t block_size = 0;
+ uint64_t blocks = 0;
+
+ if (ioctl(dev->fd, DKIOCGETBLOCKSIZE, &block_size) != 0)
+ {
+ close(dev->fd);
+ free(dev);
+ exfat_error("failed to get block size");
+ return NULL;
+ }
+ if (ioctl(dev->fd, DKIOCGETBLOCKCOUNT, &blocks) != 0)
+ {
+ close(dev->fd);
+ free(dev);
+ exfat_error("failed to get blocks count");
+ return NULL;
+ }
+ dev->size = blocks * block_size;
+ }
+ else
+#endif
+ {
+ /* works for Linux, FreeBSD, Solaris */
+ dev->size = exfat_seek(dev, 0, SEEK_END);
+ if (dev->size <= 0)
+ {
+ close(dev->fd);
+ free(dev);
+ exfat_error("failed to get size of `%s'", spec);
+ return NULL;
+ }
+ if (exfat_seek(dev, 0, SEEK_SET) == -1)
+ {
+ close(dev->fd);
+ free(dev);
+ exfat_error("failed to seek to the beginning of `%s'", spec);
+ return NULL;
+ }
+ }
+
+#ifdef USE_UBLIO
+ memset(&up, 0, sizeof(struct ublio_param));
+ up.up_blocksize = 256 * 1024;
+ up.up_items = 64;
+ up.up_grace = 32;
+ up.up_priv = &dev->fd;
+
+ dev->pos = 0;
+ dev->ufh = ublio_open(&up);
+ if (dev->ufh == NULL)
+ {
+ close(dev->fd);
+ free(dev);
+ exfat_error("failed to initialize ublio");
+ return NULL;
+ }
+#endif
+
+ return dev;
+}
+
+int exfat_close(struct exfat_dev* dev)
+{
+#ifdef USE_UBLIO
+ if (ublio_close(dev->ufh) != 0)
+ exfat_error("failed to close ublio");
+#endif
+ if (close(dev->fd) != 0)
+ {
+ free(dev);
+ exfat_error("failed to close device");
+ return 1;
+ }
+ free(dev);
+ return 0;
+}
+
+int exfat_fsync(struct exfat_dev* dev)
+{
+#ifdef USE_UBLIO
+ if (ublio_fsync(dev->ufh) != 0)
+#else
+ if (fsync(dev->fd) != 0)
+#endif
+ {
+ exfat_error("fsync failed");
+ return 1;
+ }
+ return 0;
+}
+
+enum exfat_mode exfat_get_mode(const struct exfat_dev* dev)
+{
+ return dev->mode;
+}
+
+off64_t exfat_get_size(const struct exfat_dev* dev)
+{
+ return dev->size;
+}
+
+off64_t exfat_seek(struct exfat_dev* dev, off64_t offset, int whence)
+{
+#ifdef USE_UBLIO
+ /* XXX SEEK_CUR will be handled incorrectly */
+ return dev->pos = lseek64(dev->fd, offset, whence);
+#else
+ return lseek64(dev->fd, offset, whence);
+#endif
+}
+
+ssize_t exfat_read(struct exfat_dev* dev, void* buffer, size_t size)
+{
+#ifdef USE_UBLIO
+ ssize_t result = ublio_pread(dev->ufh, buffer, size, dev->pos);
+ if (result >= 0)
+ dev->pos += size;
+ return result;
+#else
+ return read(dev->fd, buffer, size);
+#endif
+}
+
+ssize_t exfat_write(struct exfat_dev* dev, const void* buffer, size_t size)
+{
+#ifdef USE_UBLIO
+ ssize_t result = ublio_pwrite(dev->ufh, buffer, size, dev->pos);
+ if (result >= 0)
+ dev->pos += size;
+ return result;
+#else
+ return write(dev->fd, buffer, size);
+#endif
+}
+
+void exfat_pread(struct exfat_dev* dev, void* buffer, size_t size,
+ off64_t offset)
+{
+#ifdef USE_UBLIO
+ if (ublio_pread(dev->ufh, buffer, size, offset) != size)
+#else
+ if (pread64(dev->fd, buffer, size, offset) != size)
+#endif
+ exfat_bug("failed to read %zu bytes from file at %"PRIu64, size,
+ (uint64_t) offset);
+}
+
+void exfat_pwrite(struct exfat_dev* dev, const void* buffer, size_t size,
+ off64_t offset)
+{
+#ifdef USE_UBLIO
+ if (ublio_pwrite(dev->ufh, buffer, size, offset) != size)
+#else
+ if (pwrite64(dev->fd, buffer, size, offset) != size)
+#endif
+ exfat_bug("failed to write %zu bytes to file at %"PRIu64, size,
+ (uint64_t) offset);
+}
+
+ssize_t exfat_generic_pread(const struct exfat* ef, struct exfat_node* node,
+ void* buffer, size_t size, off64_t offset)
+{
+ cluster_t cluster;
+ char* bufp = buffer;
+ off64_t lsize, loffset, remainder;
+
+ if (offset >= node->size)
+ return 0;
+ if (size == 0)
+ return 0;
+
+ cluster = exfat_advance_cluster(ef, node, offset / CLUSTER_SIZE(*ef->sb));
+ if (CLUSTER_INVALID(cluster))
+ {
+ exfat_error("invalid cluster 0x%x while reading", cluster);
+ return -1;
+ }
+
+ loffset = offset % CLUSTER_SIZE(*ef->sb);
+ remainder = MIN(size, node->size - offset);
+ while (remainder > 0)
+ {
+ if (CLUSTER_INVALID(cluster))
+ {
+ exfat_error("invalid cluster 0x%x while reading", cluster);
+ return -1;
+ }
+ lsize = MIN(CLUSTER_SIZE(*ef->sb) - loffset, remainder);
+ exfat_pread(ef->dev, bufp, lsize, exfat_c2o(ef, cluster) + loffset);
+ bufp += lsize;
+ loffset = 0;
+ remainder -= lsize;
+ cluster = exfat_next_cluster(ef, node, cluster);
+ }
+ if (!ef->ro && !ef->noatime)
+ exfat_update_atime(node);
+ return size - remainder;
+}
+
+ssize_t exfat_generic_pwrite(struct exfat* ef, struct exfat_node* node,
+ const void* buffer, size_t size, off64_t offset)
+{
+ cluster_t cluster;
+ const char* bufp = buffer;
+ off64_t lsize, loffset, remainder;
+ printf("node: %s\n", node);
+ if (offset + size > node->size)
+ if (exfat_truncate(ef, node, offset + size) != 0)
+ return -1;
+ if (size == 0)
+ return 0;
+
+ cluster = exfat_advance_cluster(ef, node, offset / CLUSTER_SIZE(*ef->sb));
+ if (CLUSTER_INVALID(cluster))
+ {
+ exfat_error("invalid cluster 0x%x while writing", cluster);
+ return -1;
+ }
+
+ loffset = offset % CLUSTER_SIZE(*ef->sb);
+ remainder = size;
+ while (remainder > 0)
+ {
+ if (CLUSTER_INVALID(cluster))
+ {
+ exfat_error("invalid cluster 0x%x while writing", cluster);
+ return -1;
+ }
+ lsize = MIN(CLUSTER_SIZE(*ef->sb) - loffset, remainder);
+ exfat_pwrite(ef->dev, bufp, lsize, exfat_c2o(ef, cluster) + loffset);
+ bufp += lsize;
+ loffset = 0;
+ remainder -= lsize;
+ cluster = exfat_next_cluster(ef, node, cluster);
+ }
+ exfat_update_mtime(node);
+ return size - remainder;
+}
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