X-Git-Url: http://git.annexia.org/?p=libguestfs.git;a=blobdiff_plain;f=daemon%2Fmount.c;h=be289dade5865327f65bea16481c733c318b1173;hp=8927c6c207462bad2ac57c5270281cefc2514436;hb=463a739bf0475cf45bf03ad2c4130b2ed656686e;hpb=5922d7084d6b43f0a1a15b664c7082dfeaf584d0 diff --git a/daemon/mount.c b/daemon/mount.c index 8927c6c..be289da 100644 --- a/daemon/mount.c +++ b/daemon/mount.c @@ -24,12 +24,46 @@ #include #include #include +#include #include "daemon.h" #include "actions.h" -/* You must mount something on "/" first, hence: */ -int root_mounted = 0; +/* You must mount something on "/" first before many operations. + * Hence we have an internal function which can test if something is + * mounted on *or under* the sysroot directory. (It has to be *or + * under* because of mkmountpoint and friends). + */ +int +is_root_mounted (void) +{ + FILE *fp; + struct mntent *m; + + /* NB: Eventually we should aim to parse /proc/self/mountinfo, but + * that requires custom parsing code. + */ + fp = setmntent ("/proc/mounts", "r"); + if (fp == NULL) { + perror ("/proc/mounts"); + exit (EXIT_FAILURE); + } + + while ((m = getmntent (fp)) != NULL) { + /* Allow a mount directory like "/sysroot". */ + if (sysroot_len > 0 && STREQ (m->mnt_dir, sysroot)) { + gotit: + endmntent (fp); + return 1; + } + /* Or allow a mount directory like "/sysroot/...". */ + if (STRPREFIX (m->mnt_dir, sysroot) && m->mnt_dir[sysroot_len] == '/') + goto gotit; + } + + endmntent (fp); + return 0; +} /* The "simple mount" call offers no complex options, you can just * mount a device on a mountpoint. The variations like mount_ro, @@ -44,25 +78,31 @@ int do_mount_vfs (const char *options, const char *vfstype, const char *device, const char *mountpoint) { - int r, is_root; + int r; char *mp; char *error; + struct stat statbuf; ABS_PATH (mountpoint, , return -1); - is_root = STREQ (mountpoint, "/"); - - if (!root_mounted && !is_root) { - reply_with_error ("you must mount something on / first"); - return -1; - } - mp = sysroot_path (mountpoint); if (!mp) { reply_with_perror ("malloc"); return -1; } + /* Check the mountpoint exists and is a directory. */ + if (stat (mp, &statbuf) == -1) { + reply_with_perror ("mount: %s", mountpoint); + free (mp); + return -1; + } + if (!S_ISDIR (statbuf.st_mode)) { + reply_with_perror ("mount: %s: mount point is not a directory", mountpoint); + free (mp); + return -1; + } + if (vfstype) r = command (NULL, &error, "mount", "-o", options, "-t", vfstype, device, mp, NULL); @@ -76,9 +116,7 @@ do_mount_vfs (const char *options, const char *vfstype, return -1; } - if (is_root) - root_mounted = 1; - + free (error); return 0; } @@ -134,76 +172,76 @@ do_umount (const char *pathordevice) free (err); - /* update root_mounted? */ - return 0; } +/* Implement 'mounts' (mp==0) and 'mountpoints' (mp==1) calls. */ static char ** mounts_or_mountpoints (int mp) { - char *out, *err; - int r; + FILE *fp; + struct mntent *m; char **ret = NULL; int size = 0, alloc = 0; - char *p, *pend, *p2; - int len; - char matching[5 + sysroot_len]; - - r = command (&out, &err, "mount", NULL); - if (r == -1) { - reply_with_error ("mount: %s", err); - free (out); - free (err); - return NULL; - } - - free (err); + size_t i; + int r; - /* Lines have the format: - * /dev/foo on /mountpoint type ... + /* NB: Eventually we should aim to parse /proc/self/mountinfo, but + * that requires custom parsing code. */ - snprintf (matching, 5 + sysroot_len, " on %s", sysroot); - - p = out; - while (p) { - pend = strchr (p, '\n'); - if (pend) { - *pend = '\0'; - pend++; - } + fp = setmntent ("/proc/mounts", "r"); + if (fp == NULL) { + perror ("/proc/mounts"); + exit (EXIT_FAILURE); + } - p2 = strstr (p, matching); - if (p2 != NULL) { - *p2 = '\0'; - if (add_string (&ret, &size, &alloc, p) == -1) { - free (out); + while ((m = getmntent (fp)) != NULL) { + /* Allow a mount directory like "/sysroot". */ + if (sysroot_len > 0 && STREQ (m->mnt_dir, sysroot)) { + if (add_string (&ret, &size, &alloc, m->mnt_fsname) == -1) { + error: + endmntent (fp); return NULL; } - if (mp) { - p2 += 4 + sysroot_len; /* skip " on /sysroot" */ - len = strcspn (p2, " "); - - if (len == 0) /* .. just /sysroot, so we turn it into "/" */ - p2 = (char *) "/"; - else - p2[len] = '\0'; - - if (add_string (&ret, &size, &alloc, p2) == -1) { - free (out); - return NULL; - } - } + if (mp && + add_string (&ret, &size, &alloc, "/") == -1) + goto error; + } + /* Or allow a mount directory like "/sysroot/...". */ + if (STRPREFIX (m->mnt_dir, sysroot) && m->mnt_dir[sysroot_len] == '/') { + if (add_string (&ret, &size, &alloc, m->mnt_fsname) == -1) + goto error; + if (mp && + add_string (&ret, &size, &alloc, &m->mnt_dir[sysroot_len]) == -1) + goto error; } - - p = pend; } - free (out); + endmntent (fp); if (add_string (&ret, &size, &alloc, NULL) == -1) return NULL; + /* Convert /dev/mapper LV paths into canonical paths (RHBZ#646432). */ + for (i = 0; ret[i] != NULL; i += mp ? 2 : 1) { + if (STRPREFIX (ret[i], "/dev/mapper/") || STRPREFIX (ret[i], "/dev/dm-")) { + char *canonical; + r = lv_canonical (ret[i], &canonical); + if (r == -1) { + free_strings (ret); + return NULL; + } + if (r == 1) { + free (ret[i]); + ret[i] = canonical; + } + /* Ignore the case where r == 0. This might happen where + * eg. a LUKS /dev/mapper device is mounted, but that won't + * correspond to any LV. + */ + } + } + return ret; } @@ -242,50 +280,40 @@ compare_longest_first (const void *vp1, const void *vp2) int do_umount_all (void) { - char *out, *err; - int i, r; + FILE *fp; + struct mntent *m; char **mounts = NULL; int size = 0, alloc = 0; - char *p, *p2, *p3, *pend; - char matching[5 + sysroot_len]; + char *err; + int i, r; - r = command (&out, &err, "mount", NULL); - if (r == -1) { - reply_with_error ("mount: %s", err); - free (out); - free (err); - return -1; + /* NB: Eventually we should aim to parse /proc/self/mountinfo, but + * that requires custom parsing code. + */ + fp = setmntent ("/proc/mounts", "r"); + if (fp == NULL) { + perror ("/proc/mounts"); + exit (EXIT_FAILURE); } - free (err); - - /* Lines have the format: - * /dev/foo on /mountpoint type ... - */ - snprintf (matching, 5 + sysroot_len, " on %s", sysroot); - - p = out; - while (p) { - pend = strchr (p, '\n'); - if (pend) { - *pend = '\0'; - pend++; + while ((m = getmntent (fp)) != NULL) { + /* Allow a mount directory like "/sysroot". */ + if (sysroot_len > 0 && STREQ (m->mnt_dir, sysroot)) { + if (add_string (&mounts, &size, &alloc, m->mnt_dir) == -1) { + endmntent (fp); + return -1; + } } - - p2 = strstr (p, matching); - if (p2 != NULL) { - p2 += 4; - p3 = p2 + strcspn (p2, " "); - *p3 = '\0'; - if (add_string (&mounts, &size, &alloc, p2) == -1) { - free (out); + /* Or allow a mount directory like "/sysroot/...". */ + if (STRPREFIX (m->mnt_dir, sysroot) && m->mnt_dir[sysroot_len] == '/') { + if (add_string (&mounts, &size, &alloc, m->mnt_dir) == -1) { + endmntent (fp); return -1; } } - - p = pend; } - free (out); + + endmntent (fp); qsort (mounts, size, sizeof (char *), compare_longest_first); @@ -303,9 +331,6 @@ do_umount_all (void) free_stringslen (mounts, size); - /* We've unmounted root now, so ... */ - root_mounted = 0; - return 0; } @@ -328,7 +353,7 @@ do_mount_loop (const char *file, const char *mountpoint) } buf = sysroot_path (file); - if (!file) { + if (!buf) { reply_with_perror ("malloc"); free (mp); return -1; @@ -343,12 +368,13 @@ do_mount_loop (const char *file, const char *mountpoint) return -1; } + free (error); return 0; } /* Specialized calls mkmountpoint and rmmountpoint are really - * variations on mkdir and rmdir which do no checking and (in the - * mkmountpoint case) set the root_mounted flag. + * variations on mkdir and rmdir which do no checking of the + * is_root_mounted() flag. */ int do_mkmountpoint (const char *path) @@ -367,11 +393,6 @@ do_mkmountpoint (const char *path) return -1; } - /* Set the flag so that filesystems can be mounted here, - * not just on /sysroot. - */ - root_mounted = 1; - return 0; }