diff options
Diffstat (limited to 'contrib/fuse-lib/mount-common.c')
| -rw-r--r-- | contrib/fuse-lib/mount-common.c | 247 |
1 files changed, 247 insertions, 0 deletions
diff --git a/contrib/fuse-lib/mount-common.c b/contrib/fuse-lib/mount-common.c new file mode 100644 index 00000000000..7411e56c89b --- /dev/null +++ b/contrib/fuse-lib/mount-common.c @@ -0,0 +1,247 @@ +/* + FUSE: Filesystem in Userspace + Copyright (C) 2001-2007 Miklos Szeredi <miklos@szeredi.hu> + Copyright (c) 2010 Gluster, Inc. <http://www.gluster.com> + + This program can be distributed under the terms of the GNU LGPLv2. + See the file COPYING.LIB. +*/ + +#include "mount-gluster-compat.h" + +/* + * These functions (and gf_fuse_umount() in mount.c) + * were originally taken from libfuse as of commit 7960e99e + * (http://fuse.git.sourceforge.net/git/gitweb.cgi?p=fuse/fuse;a=commit;h=7960e99e) + * almost verbatim. What has been changed upon adoption: + * - style adopted to that of glusterfs + * - s/fprintf/gf_log/ + * - s/free/FREE/, s/malloc/MALLOC/ + * - there are some other minor things + * + * For changes that were made later and syncs with upstream, + * see the commit log. + */ + +#ifndef __NetBSD__ +static int +mtab_needs_update (const char *mnt) +{ + int res; + struct stat stbuf; + + /* If mtab is within new mount, don't touch it */ + if (strncmp (mnt, _PATH_MOUNTED, strlen (mnt)) == 0 && + _PATH_MOUNTED[strlen (mnt)] == '/') + return 0; + + /* + * Skip mtab update if /etc/mtab: + * + * - doesn't exist, + * - is a symlink, + * - is on a read-only filesystem. + */ + res = lstat (_PATH_MOUNTED, &stbuf); + if (res == -1) { + if (errno == ENOENT) + return 0; + } else { + if (S_ISLNK (stbuf.st_mode)) + return 0; + + res = access (_PATH_MOUNTED, W_OK); + if (res == -1 && errno == EROFS) + return 0; + } + + return 1; +} +#else /* __NetBSD__ */ +#define mtab_needs_update(x) 1 +#endif /* __NetBSD__ */ + +int +fuse_mnt_add_mount (const char *progname, const char *fsname, + const char *mnt, const char *type, const char *opts) +{ + int res; + int status; + sigset_t blockmask; + sigset_t oldmask; + + if (!mtab_needs_update (mnt)) + return 0; + + sigemptyset (&blockmask); + sigaddset (&blockmask, SIGCHLD); + res = sigprocmask (SIG_BLOCK, &blockmask, &oldmask); + if (res == -1) { + GFFUSE_LOGERR ("%s: sigprocmask: %s", + progname, strerror (errno)); + return -1; + } + + res = fork (); + if (res == -1) { + GFFUSE_LOGERR ("%s: fork: %s", progname, strerror (errno)); + goto out_restore; + } + if (res == 0) { + char templ[] = "/tmp/fusermountXXXXXX"; + char *tmp; + + sigprocmask (SIG_SETMASK, &oldmask, NULL); + setuid (geteuid ()); + + /* + * hide in a directory, where mount isn't able to resolve + * fsname as a valid path + */ + tmp = mkdtemp (templ); + if (!tmp) { + GFFUSE_LOGERR ("%s: failed to create temporary directory", + progname); + exit (1); + } + if (chdir (tmp)) { + GFFUSE_LOGERR ("%s: failed to chdir to %s: %s", + progname, tmp, strerror (errno)); + exit (1); + } + rmdir (tmp); + execl (_PATH_MOUNT, _PATH_MOUNT, "-i", "-f", "-t", type, + "-o", opts, fsname, mnt, NULL); + GFFUSE_LOGERR ("%s: failed to execute %s: %s", + progname, _PATH_MOUNT, strerror (errno)); + exit (1); + } + + res = waitpid (res, &status, 0); + if (res == -1) + GFFUSE_LOGERR ("%s: waitpid: %s", progname, strerror (errno)); + res = (res != -1 && status == 0) ? 0 : -1; + + out_restore: + sigprocmask (SIG_SETMASK, &oldmask, NULL); + return res; +} + +char * +fuse_mnt_resolve_path (const char *progname, const char *orig) +{ + char buf[PATH_MAX]; + char *copy; + char *dst; + char *end; + char *lastcomp; + const char *toresolv; + + if (!orig[0]) { + GFFUSE_LOGERR ("%s: invalid mountpoint '%s'", progname, orig); + return NULL; + } + + copy = strdup (orig); + if (copy == NULL) { + GFFUSE_LOGERR ("%s: failed to allocate memory", progname); + return NULL; + } + + toresolv = copy; + lastcomp = NULL; + for (end = copy + strlen (copy) - 1; end > copy && *end == '/'; end --); + if (end[0] != '/') { + char *tmp; + end[1] = '\0'; + tmp = strrchr (copy, '/'); + if (tmp == NULL) { + lastcomp = copy; + toresolv = "."; + } else { + lastcomp = tmp + 1; + if (tmp == copy) + toresolv = "/"; + } + if (strcmp (lastcomp, ".") == 0 || strcmp (lastcomp, "..") == 0) { + lastcomp = NULL; + toresolv = copy; + } + else if (tmp) + tmp[0] = '\0'; + } + if (realpath (toresolv, buf) == NULL) { + GFFUSE_LOGERR ("%s: bad mount point %s: %s", progname, orig, + strerror (errno)); + FREE (copy); + return NULL; + } + if (lastcomp == NULL) + dst = strdup (buf); + else { + dst = (char *) MALLOC (strlen (buf) + 1 + strlen (lastcomp) + 1); + if (dst) { + unsigned buflen = strlen (buf); + if (buflen && buf[buflen-1] == '/') + sprintf (dst, "%s%s", buf, lastcomp); + else + sprintf (dst, "%s/%s", buf, lastcomp); + } + } + FREE (copy); + if (dst == NULL) + GFFUSE_LOGERR ("%s: failed to allocate memory", progname); + return dst; +} + +int +fuse_mnt_umount (const char *progname, const char *abs_mnt, + const char *rel_mnt, int lazy) +{ + int res; + int status; + sigset_t blockmask; + sigset_t oldmask; + + if (!mtab_needs_update (abs_mnt)) { + res = umount2 (rel_mnt, lazy ? 2 : 0); + if (res == -1) + GFFUSE_LOGERR ("%s: failed to unmount %s: %s", + progname, abs_mnt, strerror (errno)); + return res; + } + + sigemptyset (&blockmask); + sigaddset (&blockmask, SIGCHLD); + res = sigprocmask (SIG_BLOCK, &blockmask, &oldmask); + if (res == -1) { + GFFUSE_LOGERR ("%s: sigprocmask: %s", progname, + strerror (errno)); + return -1; + } + + res = fork (); + if (res == -1) { + GFFUSE_LOGERR ("%s: fork: %s", progname, strerror (errno)); + goto out_restore; + } + if (res == 0) { + sigprocmask (SIG_SETMASK, &oldmask, NULL); + setuid (geteuid ()); + execl ("/bin/umount", "/bin/umount", "-i", rel_mnt, + lazy ? "-l" : NULL, NULL); + GFFUSE_LOGERR ("%s: failed to execute /bin/umount: %s", + progname, strerror (errno)); + exit (1); + } + res = waitpid (res, &status, 0); + if (res == -1) + GFFUSE_LOGERR ("%s: waitpid: %s", progname, strerror (errno)); + + if (status != 0) + res = -1; + + out_restore: + sigprocmask (SIG_SETMASK, &oldmask, NULL); + return res; +} |