/*
main.c (01.09.09)
FUSE-based exFAT implementation. Requires FUSE 2.6 or later.
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/>.
*/
#define FUSE_USE_VERSION 26
#include <fuse.h>
#include <errno.h>
#include <fcntl.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <exfat.h>
#include <inttypes.h>
#include <limits.h>
#include <sys/types.h>
#include <pwd.h>
#include <unistd.h>
#define exfat_debug(format, ...)
#if !defined(FUSE_VERSION) || (FUSE_VERSION < 26)
#error FUSE 2.6 or later is required
#endif
const char* default_options = "ro_fallback,allow_other,blkdev,big_writes";
struct exfat ef;
static struct exfat_node* get_node(const struct fuse_file_info* fi)
{
return (struct exfat_node*) (size_t) fi->fh;
}
static void set_node(struct fuse_file_info* fi, struct exfat_node* node)
{
fi->fh = (uint64_t) (size_t) node;
}
static int fuse_exfat_getattr(const char* path, struct stat* stbuf)
{
struct exfat_node* node;
int rc;
exfat_debug("[%s] %s", __func__, path);
rc = exfat_lookup(&ef, &node, path);
if (rc != 0)
return rc;
exfat_stat(&ef, node, stbuf);
exfat_put_node(&ef, node);
return 0;
}
static int fuse_exfat_truncate(const char* path, off64_t size)
{
struct exfat_node* node;
int rc;
exfat_debug("[%s] %s, %"PRId64, __func__, path, size);
rc = exfat_lookup(&ef, &node, path);
if (rc != 0)
return rc;
rc = exfat_truncate(&ef, node, size);
exfat_put_node(&ef, node);
return rc;
}
static int fuse_exfat_readdir(const char* path, void* buffer,
fuse_fill_dir_t filler, off64_t offset, struct fuse_file_info* fi)
{
struct exfat_node* parent;
struct exfat_node* node;
struct exfat_iterator it;
int rc;
char name[EXFAT_NAME_MAX + 1];
exfat_debug("[%s] %s", __func__, path);
rc = exfat_lookup(&ef, &parent, path);
if (rc != 0)
return rc;
if (!(parent->flags & EXFAT_ATTRIB_DIR))
{
exfat_put_node(&ef, parent);
exfat_error("`%s' is not a directory (0x%x)", path, parent->flags);
return -ENOTDIR;
}
filler(buffer, ".", NULL, 0);
filler(buffer, "..", NULL, 0);
rc = exfat_opendir(&ef, parent, &it);
if (rc != 0)
{
exfat_put_node(&ef, parent);
exfat_error("failed to open directory `%s'", path);
return rc;
}
while ((node = exfat_readdir(&ef, &it)))
{
exfat_get_name(node, name, EXFAT_NAME_MAX);
exfat_debug("[%s] %s: %s, %"PRId64" bytes, cluster 0x%x", __func__,
name, IS_CONTIGUOUS(*node) ? "contiguous" : "fragmented",
node->size, node->start_cluster);
filler(buffer, name, NULL, 0);
exfat_put_node(&ef, node);
}
exfat_closedir(&ef, &it);
exfat_put_node(&ef, parent);
return 0;
}
static int fuse_exfat_open(const char* path, struct fuse_file_info* fi)
{
struct exfat_node* node;
int rc;
exfat_debug("[%s] %s", __func__, path);
rc = exfat_lookup(&ef, &node, path);
if (rc != 0)
return rc;
set_node(fi, node);
fi->keep_cache = 1;
return 0;
}
static int fuse_exfat_release(const char* path, struct fuse_file_info* fi)
{
exfat_debug("[%s] %s", __func__, path);
exfat_put_node(&ef, get_node(fi));
return 0;
}
static int fuse_exfat_read(const char* path, char* buffer, size_t size,
off64_t offset, struct fuse_file_info* fi)
{
ssize_t ret;
exfat_debug("[%s] %s (%zu bytes)", __func__, path, size);
ret = exfat_generic_pread(&ef, get_node(fi), buffer, size, offset);
if (ret < 0)
return -EIO;
return ret;
}
static int fuse_exfat_write(const char* path, const char* buffer, size_t size,
off64_t offset, struct fuse_file_info* fi)
{
ssize_t ret;
exfat_debug("[%s] %s (%zu bytes)", __func__, path, size);
ret = exfat_generic_pwrite(&ef, get_node(fi), buffer, size, offset);
if (ret < 0)
return -EIO;
return ret;
}
static int fuse_exfat_unlink(const char* path)
{
struct exfat_node* node;
int rc;
exfat_debug("[%s] %s", __func__, path);
rc = exfat_lookup(&ef, &node, path);
if (rc != 0)
return rc;
rc = exfat_unlink(&ef, node);
exfat_put_node(&ef, node);
return rc;
}
static int fuse_exfat_rmdir(const char* path)
{
struct exfat_node* node;
int rc;
exfat_debug("[%s] %s", __func__, path);
rc = exfat_lookup(&ef, &node, path);
if (rc != 0)
return rc;
rc = exfat_rmdir(&ef, node);
exfat_put_node(&ef, node);
return rc;
}
static int fuse_exfat_mknod(const char* path, mode_t mode, dev_t dev)
{
exfat_debug("[%s] %s 0%ho", __func__, path, mode);
return exfat_mknod(&ef, path);
}
static int fuse_exfat_mkdir(const char* path, mode_t mode)
{
exfat_debug("[%s] %s 0%ho", __func__, path, mode);
return exfat_mkdir(&ef, path);
}
static int fuse_exfat_rename(const char* old_path, const char* new_path)
{
exfat_debug("[%s] %s => %s", __func__, old_path, new_path);
return exfat_rename(&ef, old_path, new_path);
}
static int fuse_exfat_utimens(const char* path, const struct timespec tv[2])
{
struct exfat_node* node;
int rc;
exfat_debug("[%s] %s", __func__, path);
rc = exfat_lookup(&ef, &node, path);
if (rc != 0)
return rc;
exfat_utimes(node, tv);
exfat_put_node(&ef, node);
return 0;
}
#ifdef __APPLE__
static int fuse_exfat_chmod(const char* path, mode_t mode)
{
exfat_debug("[%s] %s 0%ho", __func__, path, mode);
/* make OS X utilities happy */
return 0;
}
#endif
static int fuse_exfat_statfs(const char* path, struct statvfs* sfs)
{
exfat_debug("[%s]", __func__);
sfs->f_bsize = CLUSTER_SIZE(*ef.sb);
sfs->f_frsize = CLUSTER_SIZE(*ef.sb);
sfs->f_blocks = le64_to_cpu(ef.sb->sector_count) >> ef.sb->spc_bits;
sfs->f_bavail = exfat_count_free_clusters(&ef);
sfs->f_bfree = sfs->f_bavail;
sfs->f_namemax = EXFAT_NAME_MAX;
/*
Below are fake values because in exFAT there is
a) no simple way to count files;
b) no such thing as inode;
So here we assume that inode = cluster.
*/
sfs->f_files = (sfs->f_blocks - sfs->f_bfree) >> ef.sb->spc_bits;
sfs->f_favail = sfs->f_bfree >> ef.sb->spc_bits;
sfs->f_ffree = sfs->f_bavail;
return 0;
}
static void* fuse_exfat_init(struct fuse_conn_info* fci)
{
exfat_debug("[%s]", __func__);
#ifdef FUSE_CAP_BIG_WRITES
fci->want |= FUSE_CAP_BIG_WRITES;
#endif
return NULL;
}
static void fuse_exfat_destroy(void* unused)
{
exfat_debug("[%s]", __func__);
exfat_unmount(&ef);
}
static void usage(const char* prog)
{
fprintf(stderr, "Usage: %s [-d] [-o options] [-v] <device> <dir>\n", prog);
exit(1);
}
static struct fuse_operations fuse_exfat_ops =
{
.getattr = fuse_exfat_getattr,
.truncate = fuse_exfat_truncate,
.readdir = fuse_exfat_readdir,
.open = fuse_exfat_open,
.release = fuse_exfat_release,
.read = fuse_exfat_read,
.write = fuse_exfat_write,
.unlink = fuse_exfat_unlink,
.rmdir = fuse_exfat_rmdir,
.mknod = fuse_exfat_mknod,
.mkdir = fuse_exfat_mkdir,
.rename = fuse_exfat_rename,
.utimens = fuse_exfat_utimens,
#ifdef __APPLE__
.chmod = fuse_exfat_chmod,
#endif
.statfs = fuse_exfat_statfs,
.init = fuse_exfat_init,
.destroy = fuse_exfat_destroy,
};
static char* add_option(char* options, const char* name, const char* value)
{
size_t size;
if (value)
size = strlen(options) + strlen(name) + strlen(value) + 3;
else
size = strlen(options) + strlen(name) + 2;
options = realloc(options, size);
if (options == NULL)
{
exfat_error("failed to reallocate options string");
return NULL;
}
strcat(options, ",");
strcat(options, name);
if (value)
{
strcat(options, "=");
strcat(options, value);
}
return options;
}
static char* add_fsname_option(char* options, const char* spec)
{
char spec_abs[PATH_MAX];
if (realpath(spec, spec_abs) == NULL)
{
free(options);
exfat_error("failed to get absolute path for `%s'", spec);
return NULL;
}
return add_option(options, "fsname", spec_abs);
}
static char* add_user_option(char* options)
{
struct passwd* pw;
if (getuid() == 0)
return options;
pw = getpwuid(getuid());
if (pw == NULL || pw->pw_name == NULL)
{
free(options);
exfat_error("failed to determine username");
return NULL;
}
return add_option(options, "user", pw->pw_name);
}
static char* add_blksize_option(char* options, long cluster_size)
{
long page_size = sysconf(_SC_PAGESIZE);
char blksize[20];
if (page_size < 1)
page_size = 0x1000;
snprintf(blksize, sizeof(blksize), "%ld", MIN(page_size, cluster_size));
return add_option(options, "blksize", blksize);
}
static char* add_fuse_options(char* options, const char* spec)
{
options = add_fsname_option(options, spec);
if (options == NULL)
return NULL;
options = add_user_option(options);
if (options == NULL)
return NULL;
options = add_blksize_option(options, CLUSTER_SIZE(*ef.sb));
if (options == NULL)
return NULL;
return options;
}
int main(int argc, char* argv[])
{
struct fuse_args mount_args = FUSE_ARGS_INIT(0, NULL);
struct fuse_args newfs_args = FUSE_ARGS_INIT(0, NULL);
const char* spec = NULL;
const char* mount_point = NULL;
char* mount_options;
int debug = 0;
struct fuse_chan* fc = NULL;
struct fuse* fh = NULL;
char** pp;
printf("FUSE exfat %u.%u.%u\n",
EXFAT_VERSION_MAJOR, EXFAT_VERSION_MINOR, EXFAT_VERSION_PATCH);
mount_options = strdup(default_options);
if (mount_options == NULL)
{
exfat_error("failed to allocate options string");
return 1;
}
for (pp = argv + 1; *pp; pp++)
{
if (strcmp(*pp, "-o") == 0)
{
pp++;
if (*pp == NULL)
usage(argv[0]);
mount_options = add_option(mount_options, *pp, NULL);
if (mount_options == NULL)
return 1;
}
else if (strcmp(*pp, "-d") == 0)
debug = 1;
else if (strcmp(*pp, "-v") == 0)
{
free(mount_options);
puts("Copyright (C) 2010-2012 Andrew Nayenko");
return 0;
}
else if (spec == NULL)
spec = *pp;
else if (mount_point == NULL)
mount_point = *pp;
else
{
free(mount_options);
usage(argv[0]);
}
}
if (spec == NULL || mount_point == NULL)
{
free(mount_options);
usage(argv[0]);
}
if (exfat_mount(&ef, spec, mount_options) != 0)
{
free(mount_options);
return 1;
}
if (ef.ro == -1) /* read-only fallback was used */
{
mount_options = add_option(mount_options, "ro", NULL);
if (mount_options == NULL)
{
exfat_unmount(&ef);
return 1;
}
}
mount_options = add_fuse_options(mount_options, spec);
if (mount_options == NULL)
{
exfat_unmount(&ef);
return 1;
}
/* create arguments for fuse_mount() */
if (fuse_opt_add_arg(&mount_args, "exfat") != 0 ||
fuse_opt_add_arg(&mount_args, "-o") != 0 ||
fuse_opt_add_arg(&mount_args, mount_options) != 0)
{
exfat_unmount(&ef);
free(mount_options);
return 1;
}
free(mount_options);
/* create FUSE mount point */
fc = fuse_mount(mount_point, &mount_args);
fuse_opt_free_args(&mount_args);
if (fc == NULL)
{
exfat_unmount(&ef);
return 1;
}
/* create arguments for fuse_new() */
if (fuse_opt_add_arg(&newfs_args, "") != 0 ||
(debug && fuse_opt_add_arg(&newfs_args, "-d") != 0))
{
fuse_unmount(mount_point, fc);
exfat_unmount(&ef);
return 1;
}
/* create new FUSE file system */
fh = fuse_new(fc, &newfs_args, &fuse_exfat_ops,
sizeof(struct fuse_operations), NULL);
fuse_opt_free_args(&newfs_args);
if (fh == NULL)
{
fuse_unmount(mount_point, fc);
exfat_unmount(&ef);
return 1;
}
/* exit session on HUP, TERM and INT signals and ignore PIPE signal */
if (fuse_set_signal_handlers(fuse_get_session(fh)) != 0)
{
fuse_unmount(mount_point, fc);
fuse_destroy(fh);
exfat_unmount(&ef);
exfat_error("failed to set signal handlers");
return 1;
}
/* go to background (unless "-d" option is passed) and run FUSE
main loop */
if (fuse_daemonize(debug) == 0)
{
if (fuse_loop(fh) != 0)
exfat_error("FUSE loop failure");
}
else
exfat_error("failed to daemonize");
fuse_remove_signal_handlers(fuse_get_session(fh));
/* note that fuse_unmount() must be called BEFORE fuse_destroy() */
fuse_unmount(mount_point, fc);
fuse_destroy(fh);
return 0;
}
