/
fuse.c
1492 lines (1217 loc) · 35.7 KB
/
fuse.c
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/* libguestfs
* Copyright (C) 2009-2014 Red Hat Inc.
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2 of the License, or (at your option) any later version.
*
* This library 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
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with this library; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
*/
#include <config.h>
#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <errno.h>
#include <sys/types.h>
#include <sys/wait.h>
#if HAVE_FUSE
/* See <attr/xattr.h> */
#ifndef ENOATTR
#define ENOATTR ENODATA
#endif
#define FUSE_USE_VERSION 26
#include <fuse.h>
#include <fuse_lowlevel.h>
#endif
#include "cloexec.h"
#include "glthread/lock.h"
#include "hash.h"
#include "hash-pjw.h"
#include "guestfs.h"
#include "guestfs-internal.h"
#include "guestfs-internal-actions.h"
#include "guestfs_protocol.h"
#if HAVE_FUSE
/* Functions handling the directory cache. */
static int init_dir_caches (guestfs_h *);
static void free_dir_caches (guestfs_h *);
static void dir_cache_remove_all_expired (guestfs_h *, time_t now);
static void dir_cache_invalidate (guestfs_h *, const char *path);
static int lsc_insert (guestfs_h *, const char *path, const char *name, time_t now, struct stat const *statbuf);
static int xac_insert (guestfs_h *, const char *path, const char *name, time_t now, struct guestfs_xattr_list *xattrs);
static int rlc_insert (guestfs_h *, const char *path, const char *name, time_t now, char *link);
static const struct stat *lsc_lookup (guestfs_h *, const char *pathname);
static const struct guestfs_xattr_list *xac_lookup (guestfs_h *, const char *pathname);
static const char *rlc_lookup (guestfs_h *, const char *pathname);
/* This lock protects access to g->localmountpoint. */
gl_lock_define_initialized (static, mount_local_lock);
#define DECL_G() guestfs_h *g = fuse_get_context()->private_data
#define DEBUG_CALL(fs,...) \
if (g->ml_debug_calls) { \
debug (g, \
"%s: %s (" fs ")", \
g->localmountpoint, __func__, ## __VA_ARGS__); \
}
#define RETURN_ERRNO \
do { \
int ret_errno = guestfs_last_errno (g); \
\
/* 0 doesn't mean "no error". It means the errno was not \
* captured. Therefore we have to substitute an errno here. \
*/ \
if (ret_errno == 0) \
ret_errno = EINVAL; \
\
return -ret_errno; \
} while (0)
static struct guestfs_xattr_list *
copy_xattr_list (guestfs_h *g, const struct guestfs_xattr *first, size_t num)
{
struct guestfs_xattr_list *xattrs;
xattrs = malloc (sizeof *xattrs);
if (xattrs == NULL) {
perrorf (g, "malloc");
return NULL;
}
xattrs->len = num;
xattrs->val = malloc (num * sizeof (struct guestfs_xattr));
if (xattrs->val == NULL) {
perrorf (g, "malloc");
free (xattrs);
return NULL;
}
size_t i;
for (i = 0; i < num; ++i) {
xattrs->val[i].attrname = strdup (first[i].attrname);
xattrs->val[i].attrval_len = first[i].attrval_len;
xattrs->val[i].attrval = malloc (first[i].attrval_len);
memcpy (xattrs->val[i].attrval, first[i].attrval, first[i].attrval_len);
}
return xattrs;
}
static int
mount_local_readdir (const char *path, void *buf, fuse_fill_dir_t filler,
off_t offset, struct fuse_file_info *fi)
{
DECL_G ();
DEBUG_CALL ("%s, %p, %ld", path, buf, (long) offset);
time_t now;
time (&now);
dir_cache_remove_all_expired (g, now);
CLEANUP_FREE_DIRENT_LIST struct guestfs_dirent_list *ents =
guestfs_readdir (g, path);
if (ents == NULL)
RETURN_ERRNO;
size_t i;
for (i = 0; i < ents->len; ++i) {
struct stat stat;
memset (&stat, 0, sizeof stat);
stat.st_ino = ents->val[i].ino;
switch (ents->val[i].ftyp) {
case 'b': stat.st_mode = S_IFBLK; break;
case 'c': stat.st_mode = S_IFCHR; break;
case 'd': stat.st_mode = S_IFDIR; break;
case 'f': stat.st_mode = S_IFIFO; break;
case 'l': stat.st_mode = S_IFLNK; break;
case 'r': stat.st_mode = S_IFREG; break;
case 's': stat.st_mode = S_IFSOCK; break;
case 'u':
case '?':
default: stat.st_mode = 0;
}
/* Copied from the example, which also ignores 'offset'. I'm
* not quite sure how this is ever supposed to work on large
* directories. XXX
*/
if (filler (buf, ents->val[i].name, &stat, 0))
break;
}
/* Now prepopulate the directory caches. This step is just an
* optimization, don't worry if it fails.
*/
char **names = malloc ((ents->len + 1) * sizeof (char *));
if (names) {
for (i = 0; i < ents->len; ++i)
names[i] = ents->val[i].name;
names[i] = NULL;
CLEANUP_FREE_STAT_LIST struct guestfs_stat_list *ss =
guestfs_lstatlist (g, path, names);
if (ss) {
for (i = 0; i < ss->len; ++i) {
if (ss->val[i].ino >= 0) {
struct stat statbuf;
memset (&statbuf, 0, sizeof statbuf);
statbuf.st_dev = ss->val[i].dev;
statbuf.st_ino = ss->val[i].ino;
statbuf.st_mode = ss->val[i].mode;
statbuf.st_nlink = ss->val[i].nlink;
statbuf.st_uid = ss->val[i].uid;
statbuf.st_gid = ss->val[i].gid;
statbuf.st_rdev = ss->val[i].rdev;
statbuf.st_size = ss->val[i].size;
statbuf.st_blksize = ss->val[i].blksize;
statbuf.st_blocks = ss->val[i].blocks;
statbuf.st_atime = ss->val[i].atime;
statbuf.st_mtime = ss->val[i].mtime;
statbuf.st_ctime = ss->val[i].ctime;
lsc_insert (g, path, names[i], now, &statbuf);
}
}
}
CLEANUP_FREE_XATTR_LIST struct guestfs_xattr_list *xattrs =
guestfs_lxattrlist (g, path, names);
if (xattrs) {
size_t ni, num;
struct guestfs_xattr *first;
struct guestfs_xattr_list *copy;
for (i = 0, ni = 0; i < xattrs->len; ++i, ++ni) {
/* assert (strlen (xattrs->val[i].attrname) == 0); */
if (xattrs->val[i].attrval_len > 0) {
++i;
first = &xattrs->val[i];
num = 0;
for (; i < xattrs->len && strlen (xattrs->val[i].attrname) > 0; ++i)
num++;
copy = copy_xattr_list (g, first, num);
if (copy)
xac_insert (g, path, names[ni], now, copy);
i--;
}
}
}
char **links = guestfs_readlinklist (g, path, names);
if (links) {
for (i = 0; names[i] != NULL; ++i) {
if (links[i][0])
/* Note that rlc_insert owns the string links[i] after this, */
rlc_insert (g, path, names[i], now, links[i]);
else
/* which is why we have to free links[i] here. */
free (links[i]);
}
free (links); /* free the array, not the strings */
}
free (names);
}
return 0;
}
static int
mount_local_getattr (const char *path, struct stat *statbuf)
{
DECL_G ();
DEBUG_CALL ("%s, %p", path, statbuf);
const struct stat *buf;
buf = lsc_lookup (g, path);
if (buf) {
memcpy (statbuf, buf, sizeof *statbuf);
return 0;
}
CLEANUP_FREE_STAT struct guestfs_stat *r = guestfs_lstat (g, path);
if (r == NULL)
RETURN_ERRNO;
memset (statbuf, 0, sizeof *statbuf);
statbuf->st_dev = r->dev;
statbuf->st_ino = r->ino;
statbuf->st_mode = r->mode;
statbuf->st_nlink = r->nlink;
statbuf->st_uid = r->uid;
statbuf->st_gid = r->gid;
statbuf->st_rdev = r->rdev;
statbuf->st_size = r->size;
statbuf->st_blksize = r->blksize;
statbuf->st_blocks = r->blocks;
statbuf->st_atime = r->atime;
statbuf->st_mtime = r->mtime;
statbuf->st_ctime = r->ctime;
return 0;
}
/* Nautilus loves to use access(2) to test everything about a file,
* such as whether it's executable. Therefore treat this a lot like
* mount_local_getattr.
*/
static int
mount_local_access (const char *path, int mask)
{
DECL_G ();
DEBUG_CALL ("%s, %d", path, mask);
struct stat statbuf;
int r;
if (g->ml_read_only && (mask & W_OK))
return -EROFS;
r = mount_local_getattr (path, &statbuf);
if (r < 0 || mask == F_OK)
return r;
struct fuse_context *fuse = fuse_get_context ();
int ok = 1;
if (mask & R_OK)
ok = ok &&
( fuse->uid == statbuf.st_uid ? statbuf.st_mode & S_IRUSR
: fuse->gid == statbuf.st_gid ? statbuf.st_mode & S_IRGRP
: statbuf.st_mode & S_IROTH);
if (mask & W_OK)
ok = ok &&
( fuse->uid == statbuf.st_uid ? statbuf.st_mode & S_IWUSR
: fuse->gid == statbuf.st_gid ? statbuf.st_mode & S_IWGRP
: statbuf.st_mode & S_IWOTH);
if (mask & X_OK)
ok = ok &&
( fuse->uid == statbuf.st_uid ? statbuf.st_mode & S_IXUSR
: fuse->gid == statbuf.st_gid ? statbuf.st_mode & S_IXGRP
: statbuf.st_mode & S_IXOTH);
return ok ? 0 : -EACCES;
}
static int
mount_local_readlink (const char *path, char *buf, size_t size)
{
DECL_G ();
DEBUG_CALL ("%s, %p, %zu", path, buf, size);
const char *r;
int free_it = 0;
r = rlc_lookup (g, path);
if (!r) {
r = guestfs_readlink (g, path);
if (r == NULL)
RETURN_ERRNO;
free_it = 1;
}
/* Note this is different from the real readlink(2) syscall. FUSE wants
* the string to be always nul-terminated, even if truncated.
*/
size_t len = strlen (r);
if (len > size - 1)
len = size - 1;
memcpy (buf, r, len);
buf[len] = '\0';
if (free_it) {
char *tmp = (char *) r;
free (tmp);
}
return 0;
}
static int
mount_local_mknod (const char *path, mode_t mode, dev_t rdev)
{
DECL_G ();
DEBUG_CALL ("%s, 0%o, 0x%lx", path, mode, (long) rdev);
int r;
if (g->ml_read_only) return -EROFS;
dir_cache_invalidate (g, path);
r = guestfs_mknod (g, mode, major (rdev), minor (rdev), path);
if (r == -1)
RETURN_ERRNO;
return 0;
}
static int
mount_local_mkdir (const char *path, mode_t mode)
{
DECL_G ();
DEBUG_CALL ("%s, 0%o", path, mode);
int r;
if (g->ml_read_only) return -EROFS;
dir_cache_invalidate (g, path);
r = guestfs_mkdir_mode (g, path, mode);
if (r == -1)
RETURN_ERRNO;
return 0;
}
static int
mount_local_unlink (const char *path)
{
DECL_G ();
DEBUG_CALL ("%s", path);
int r;
if (g->ml_read_only) return -EROFS;
dir_cache_invalidate (g, path);
r = guestfs_rm (g, path);
if (r == -1)
RETURN_ERRNO;
return 0;
}
static int
mount_local_rmdir (const char *path)
{
DECL_G ();
DEBUG_CALL ("%s", path);
int r;
if (g->ml_read_only) return -EROFS;
dir_cache_invalidate (g, path);
r = guestfs_rmdir (g, path);
if (r == -1)
RETURN_ERRNO;
return 0;
}
static int
mount_local_symlink (const char *from, const char *to)
{
DECL_G ();
DEBUG_CALL ("%s, %s", from, to);
int r;
if (g->ml_read_only) return -EROFS;
dir_cache_invalidate (g, to);
r = guestfs_ln_s (g, from, to);
if (r == -1)
RETURN_ERRNO;
return 0;
}
static int
mount_local_rename (const char *from, const char *to)
{
DECL_G ();
DEBUG_CALL ("%s, %s", from, to);
int r;
if (g->ml_read_only) return -EROFS;
dir_cache_invalidate (g, from);
dir_cache_invalidate (g, to);
r = guestfs_rename (g, from, to);
if (r == -1)
RETURN_ERRNO;
return 0;
}
static int
mount_local_link (const char *from, const char *to)
{
DECL_G ();
DEBUG_CALL ("%s, %s", from, to);
int r;
if (g->ml_read_only) return -EROFS;
dir_cache_invalidate (g, from);
dir_cache_invalidate (g, to);
r = guestfs_ln (g, from, to);
if (r == -1)
RETURN_ERRNO;
return 0;
}
static int
mount_local_chmod (const char *path, mode_t mode)
{
DECL_G ();
DEBUG_CALL ("%s, 0%o", path, mode);
int r;
if (g->ml_read_only) return -EROFS;
dir_cache_invalidate (g, path);
r = guestfs_chmod (g, mode, path);
if (r == -1)
RETURN_ERRNO;
return 0;
}
static int
mount_local_chown (const char *path, uid_t uid, gid_t gid)
{
DECL_G ();
DEBUG_CALL ("%s, %ld, %ld", path, (long) uid, (long) gid);
int r;
if (g->ml_read_only) return -EROFS;
dir_cache_invalidate (g, path);
r = guestfs_lchown (g, uid, gid, path);
if (r == -1)
RETURN_ERRNO;
return 0;
}
static int
mount_local_truncate (const char *path, off_t size)
{
DECL_G ();
DEBUG_CALL ("%s, %ld", path, (long) size);
int r;
if (g->ml_read_only) return -EROFS;
dir_cache_invalidate (g, path);
r = guestfs_truncate_size (g, path, size);
if (r == -1)
RETURN_ERRNO;
return 0;
}
static int
mount_local_utimens (const char *path, const struct timespec ts[2])
{
DECL_G ();
DEBUG_CALL ("%s, [{ %ld, %ld }, { %ld, %ld }]",
path, ts[0].tv_sec, ts[0].tv_nsec, ts[1].tv_sec, ts[1].tv_nsec);
int r;
if (g->ml_read_only) return -EROFS;
dir_cache_invalidate (g, path);
time_t atsecs = ts[0].tv_sec;
long atnsecs = ts[0].tv_nsec;
time_t mtsecs = ts[1].tv_sec;
long mtnsecs = ts[1].tv_nsec;
#ifdef UTIME_NOW
if (atnsecs == UTIME_NOW)
atnsecs = -1;
#endif
#ifdef UTIME_OMIT
if (atnsecs == UTIME_OMIT)
atnsecs = -2;
#endif
#ifdef UTIME_NOW
if (mtnsecs == UTIME_NOW)
mtnsecs = -1;
#endif
#ifdef UTIME_OMIT
if (mtnsecs == UTIME_OMIT)
mtnsecs = -2;
#endif
r = guestfs_utimens (g, path, atsecs, atnsecs, mtsecs, mtnsecs);
if (r == -1)
RETURN_ERRNO;
return 0;
}
/* All this function needs to do is to check that the requested open
* flags are valid. See the notes in <fuse/fuse.h>.
*/
static int
mount_local_open (const char *path, struct fuse_file_info *fi)
{
DECL_G ();
DEBUG_CALL ("%s, 0%o", path, fi->flags);
int flags = fi->flags & O_ACCMODE;
if (g->ml_read_only && flags != O_RDONLY)
return -EROFS;
return 0;
}
static int
mount_local_read (const char *path, char *buf, size_t size, off_t offset,
struct fuse_file_info *fi)
{
DECL_G ();
DEBUG_CALL ("%s, %p, %zu, %ld", path, buf, size, (long) offset);
char *r;
size_t rsize;
/* The guestfs protocol limits size to somewhere over 2MB. We just
* reduce the requested size here accordingly and push the problem
* up to every user. http://www.jwz.org/doc/worse-is-better.html
*/
const size_t limit = 2 * 1024 * 1024;
if (size > limit)
size = limit;
r = guestfs_pread (g, path, size, offset, &rsize);
if (r == NULL)
RETURN_ERRNO;
/* This should never happen, but at least it stops us overflowing
* the output buffer if it does happen.
*/
if (rsize > size)
rsize = size;
memcpy (buf, r, rsize);
free (r);
return rsize;
}
static int
mount_local_write (const char *path, const char *buf, size_t size,
off_t offset, struct fuse_file_info *fi)
{
DECL_G ();
DEBUG_CALL ("%s, %p, %zu, %ld", path, buf, size, (long) offset);
if (g->ml_read_only) return -EROFS;
dir_cache_invalidate (g, path);
/* See mount_local_read. */
const size_t limit = 2 * 1024 * 1024;
if (size > limit)
size = limit;
int r;
r = guestfs_pwrite (g, path, buf, size, offset);
if (r == -1)
RETURN_ERRNO;
return r;
}
static int
mount_local_statfs (const char *path, struct statvfs *stbuf)
{
DECL_G ();
DEBUG_CALL ("%s, %p", path, stbuf);
CLEANUP_FREE_STATVFS struct guestfs_statvfs *r = guestfs_statvfs (g, path);
if (r == NULL)
RETURN_ERRNO;
stbuf->f_bsize = r->bsize;
stbuf->f_frsize = r->frsize;
stbuf->f_blocks = r->blocks;
stbuf->f_bfree = r->bfree;
stbuf->f_bavail = r->bavail;
stbuf->f_files = r->files;
stbuf->f_ffree = r->ffree;
stbuf->f_favail = r->favail;
stbuf->f_fsid = r->fsid;
stbuf->f_flag = r->flag;
stbuf->f_namemax = r->namemax;
return 0;
}
static int
mount_local_release (const char *path, struct fuse_file_info *fi)
{
DECL_G ();
DEBUG_CALL ("%s", path);
/* Just a stub. This method is optional and can safely be left
* unimplemented.
*/
return 0;
}
/* Emulate this by calling sync. */
static int
mount_local_fsync (const char *path, int isdatasync,
struct fuse_file_info *fi)
{
DECL_G ();
DEBUG_CALL ("%s, %d", path, isdatasync);
int r;
r = guestfs_sync (g);
if (r == -1)
RETURN_ERRNO;
return 0;
}
static int
mount_local_setxattr (const char *path, const char *name, const char *value,
size_t size, int flags)
{
DECL_G ();
DEBUG_CALL ("%s, %s, %p, %zu", path, name, value, size);
int r;
if (g->ml_read_only) return -EROFS;
dir_cache_invalidate (g, path);
/* XXX Underlying guestfs(3) API doesn't understand the flags. */
r = guestfs_lsetxattr (g, name, value, size, path);
if (r == -1)
RETURN_ERRNO;
return 0;
}
/* The guestfs(3) API for getting xattrs is much easier to use
* than the real syscall. Unfortunately we now have to emulate
* the real syscall using that API :-(
*/
static int
mount_local_getxattr (const char *path, const char *name, char *value,
size_t size)
{
DECL_G ();
DEBUG_CALL ("%s, %s, %p, %zu", path, name, value, size);
const struct guestfs_xattr_list *xattrs;
int free_attrs = 0;
ssize_t r;
size_t i, sz;
xattrs = xac_lookup (g, path);
if (xattrs == NULL) {
xattrs = guestfs_lgetxattrs (g, path);
if (xattrs == NULL)
RETURN_ERRNO;
free_attrs = 1;
}
/* Find the matching attribute (index in 'i'). */
for (i = 0; i < xattrs->len; ++i) {
if (STREQ (xattrs->val[i].attrname, name))
break;
}
if (i == xattrs->len) { /* not found */
r = -ENOATTR;
goto out;
}
/* The getxattr man page is unclear, but if value == NULL then we
* return the space required (the caller then makes a second syscall
* after allocating the required amount of space). If value != NULL
* then it's not clear what we should do, but it appears we should
* copy as much as possible and return -ERANGE if there's not enough
* space in the buffer.
*/
sz = xattrs->val[i].attrval_len;
if (value == NULL) {
r = sz;
goto out;
}
if (sz <= size)
r = sz;
else {
r = -ERANGE;
sz = size;
}
memcpy (value, xattrs->val[i].attrval, sz);
out:
if (free_attrs)
guestfs_free_xattr_list ((struct guestfs_xattr_list *) xattrs);
return r;
}
/* Ditto as above. */
static int
mount_local_listxattr (const char *path, char *list, size_t size)
{
DECL_G ();
DEBUG_CALL ("%s, %p, %zu", path, list, size);
const struct guestfs_xattr_list *xattrs;
int free_attrs = 0;
xattrs = xac_lookup (g, path);
if (xattrs == NULL) {
xattrs = guestfs_lgetxattrs (g, path);
if (xattrs == NULL)
RETURN_ERRNO;
free_attrs = 1;
}
/* Calculate how much space is required to hold the result. */
size_t space = 0;
size_t len;
size_t i;
for (i = 0; i < xattrs->len; ++i) {
len = strlen (xattrs->val[i].attrname) + 1;
space += len;
}
/* The listxattr man page is unclear, but if list == NULL then we
* return the space required (the caller then makes a second syscall
* after allocating the required amount of space). If list != NULL
* then it's not clear what we should do, but it appears we should
* copy as much as possible and return -ERANGE if there's not enough
* space in the buffer.
*/
ssize_t r;
if (list == NULL) {
r = space;
goto out;
}
r = 0;
for (i = 0; i < xattrs->len; ++i) {
len = strlen (xattrs->val[i].attrname) + 1;
if (size >= len) {
memcpy (list, xattrs->val[i].attrname, len);
size -= len;
list += len;
r += len;
} else {
r = -ERANGE;
break;
}
}
out:
if (free_attrs)
guestfs_free_xattr_list ((struct guestfs_xattr_list *) xattrs);
return r;
}
static int
mount_local_removexattr(const char *path, const char *name)
{
DECL_G ();
DEBUG_CALL ("%s, %s", path, name);
int r;
if (g->ml_read_only) return -EROFS;
dir_cache_invalidate (g, path);
r = guestfs_lremovexattr (g, name, path);
if (r == -1)
RETURN_ERRNO;
return 0;
}
static int
mount_local_flush(const char *path, struct fuse_file_info *fi)
{
DECL_G ();
DEBUG_CALL ("%s", path);
/* Just a stub. This method is called whenever FUSE wants to flush the
* pending changes (f.ex. to attributes) to a file. Since we don't have
* anything to do and don't want FUSE to think something went badly,
* just return 0.
*/
return 0;
}
static struct fuse_operations mount_local_operations = {
.getattr = mount_local_getattr,
.access = mount_local_access,
.readlink = mount_local_readlink,
.readdir = mount_local_readdir,
.mknod = mount_local_mknod,
.mkdir = mount_local_mkdir,
.symlink = mount_local_symlink,
.unlink = mount_local_unlink,
.rmdir = mount_local_rmdir,
.rename = mount_local_rename,
.link = mount_local_link,
.chmod = mount_local_chmod,
.chown = mount_local_chown,
.truncate = mount_local_truncate,
.utimens = mount_local_utimens,
.open = mount_local_open,
.read = mount_local_read,
.write = mount_local_write,
.statfs = mount_local_statfs,
.release = mount_local_release,
.fsync = mount_local_fsync,
.setxattr = mount_local_setxattr,
.getxattr = mount_local_getxattr,
.listxattr = mount_local_listxattr,
.removexattr = mount_local_removexattr,
.flush = mount_local_flush,
};
int
guestfs__mount_local (guestfs_h *g, const char *localmountpoint,
const struct guestfs_mount_local_argv *optargs)
{
const char *t;
struct fuse_args args = FUSE_ARGS_INIT (0, NULL);
struct fuse_chan *ch;
int fd;
/* You can only mount each handle in one place in one thread. */
gl_lock_lock (mount_local_lock);
t = g->localmountpoint;
gl_lock_unlock (mount_local_lock);
if (t) {
error (g, _("filesystem is already mounted in another thread"));
return -1;
}
if (optargs->bitmask & GUESTFS_MOUNT_LOCAL_READONLY_BITMASK)
g->ml_read_only = optargs->readonly;
else
g->ml_read_only = 0;
if (optargs->bitmask & GUESTFS_MOUNT_LOCAL_CACHETIMEOUT_BITMASK)
g->ml_dir_cache_timeout = optargs->cachetimeout;
else
g->ml_dir_cache_timeout = 60;
if (optargs->bitmask & GUESTFS_MOUNT_LOCAL_DEBUGCALLS_BITMASK)
g->ml_debug_calls = optargs->debugcalls;
else
g->ml_debug_calls = 0;
/* Initialize the directory caches in the handle. */
if (init_dir_caches (g) == -1)
return -1;
/* Create the FUSE 'args'. */
/* XXX we don't have a program name */
if (fuse_opt_add_arg (&args, "guestfs_mount_local") == -1) {
arg_error:
perrorf (g, _("fuse_opt_add_arg: %s"), localmountpoint);
fuse_opt_free_args (&args);
guestfs___free_fuse (g);
return -1;
}
if (optargs->bitmask & GUESTFS_MOUNT_LOCAL_OPTIONS_BITMASK) {
if (fuse_opt_add_arg (&args, "-o") == -1 ||
fuse_opt_add_arg (&args, optargs->options) == -1)
goto arg_error;
}
debug (g, "%s: fuse_mount %s", __func__, localmountpoint);
/* Create the FUSE mountpoint. */
ch = fuse_mount (localmountpoint, &args);
if (ch == NULL) {
perrorf (g, _("fuse_mount: %s"), localmountpoint);
fuse_opt_free_args (&args);
guestfs___free_fuse (g);
return -1;
}
/* Set F_CLOEXEC on the channel. XXX libfuse should do this. */
fd = fuse_chan_fd (ch);
if (fd >= 0)
set_cloexec_flag (fd, 1);
debug (g, "%s: fuse_new", __func__);
/* Create the FUSE handle. */
g->fuse = fuse_new (ch, &args,
&mount_local_operations, sizeof mount_local_operations,
g);
if (!g->fuse) {
perrorf (g, _("fuse_new: %s"), localmountpoint);
fuse_unmount (localmountpoint, ch);
fuse_opt_free_args (&args);