unsigned long flags; /* Mount flags used by EMPTY_DIR and TMPFS. Do not include MS_RDONLY here, but please use read_only. */
unsigned n_followed;
LIST_HEAD(MountOptions, image_options_const);
+ char **overlay_layers;
} MountEntry;
typedef struct MountList {
p->unprefixed_path_malloc = mfree(p->unprefixed_path_malloc);
p->source_malloc = mfree(p->source_malloc);
p->options_malloc = mfree(p->options_malloc);
+ p->overlay_layers = strv_free(p->overlay_layers);
}
static void mount_list_done(MountList *ml) {
size_t n,
char **extension_directories) {
- _cleanup_strv_free_ char **overlays = NULL;
+ char ***overlays = NULL;
+ size_t n_overlays = 0;
int r;
assert(ml);
assert(extension_dir);
- /* Prepare a list of overlays, that will have as each element a string suitable for being
- * passed as a lowerdir= parameter, so start with the hierarchy on the root.
+ n_overlays = strv_length(hierarchies);
+ if (n_overlays == 0)
+ return 0;
+
+ /* Prepare a list of overlays, that will have as each element a strv containing all the layers that
+ * will later be concatenated as a lowerdir= parameter for the mount operation.
* The overlays vector will have the same number of elements and will correspond to the
* hierarchies vector, so they can be iterated upon together. */
- STRV_FOREACH(hierarchy, hierarchies) {
- _cleanup_free_ char *prefixed_hierarchy = NULL;
-
- prefixed_hierarchy = path_join(root, *hierarchy);
- if (!prefixed_hierarchy)
- return -ENOMEM;
+ overlays = new0(char**, n_overlays);
+ if (!overlays)
+ return -ENOMEM;
- r = strv_consume(&overlays, TAKE_PTR(prefixed_hierarchy));
- if (r < 0)
- return r;
- }
+ CLEANUP_ARRAY(overlays, n_overlays, strv_free_many);
/* First, prepare a mount for each image, but these won't be visible to the unit, instead
* they will be mounted in our propagate directory, and used as a source for the overlay. */
return -ENOMEM;
for (size_t j = 0; hierarchies && hierarchies[j]; ++j) {
- _cleanup_free_ char *prefixed_hierarchy = NULL, *escaped = NULL, *lowerdir = NULL;
-
- prefixed_hierarchy = path_join(mount_point, hierarchies[j]);
+ char *prefixed_hierarchy = path_join(mount_point, hierarchies[j]);
if (!prefixed_hierarchy)
return -ENOMEM;
- escaped = shell_escape(prefixed_hierarchy, ",:");
- if (!escaped)
- return -ENOMEM;
-
- /* Note that lowerdir= parameters are in 'reverse' order, so the
- * top-most directory in the overlay comes first in the list. */
- lowerdir = strjoin(escaped, ":", overlays[j]);
- if (!lowerdir)
- return -ENOMEM;
-
- free_and_replace(overlays[j], lowerdir);
+ r = strv_consume(&overlays[j], TAKE_PTR(prefixed_hierarchy));
+ if (r < 0)
+ return r;
}
MountEntry *me = mount_list_extend(ml);
if (!me)
- return log_oom_debug();
+ return -ENOMEM;
*me = (MountEntry) {
.path_malloc = TAKE_PTR(mount_point),
return -ENOMEM;
for (size_t j = 0; hierarchies && hierarchies[j]; ++j) {
- _cleanup_free_ char *prefixed_hierarchy = NULL, *escaped = NULL, *lowerdir = NULL;
-
- prefixed_hierarchy = path_join(mount_point, hierarchies[j]);
+ char *prefixed_hierarchy = path_join(mount_point, hierarchies[j]);
if (!prefixed_hierarchy)
return -ENOMEM;
- escaped = shell_escape(prefixed_hierarchy, ",:");
- if (!escaped)
- return -ENOMEM;
-
- /* Note that lowerdir= parameters are in 'reverse' order, so the
- * top-most directory in the overlay comes first in the list. */
- lowerdir = strjoin(escaped, ":", overlays[j]);
- if (!lowerdir)
- return -ENOMEM;
-
- free_and_replace(overlays[j], lowerdir);
+ r = strv_consume(&overlays[j], TAKE_PTR(prefixed_hierarchy));
+ if (r < 0)
+ return r;
}
MountEntry *me = mount_list_extend(ml);
if (!me)
- return log_oom_debug();
+ return -ENOMEM;
*me = (MountEntry) {
.path_malloc = TAKE_PTR(mount_point),
MountEntry *me = mount_list_extend(ml);
if (!me)
- return log_oom_debug();
+ return -ENOMEM;
*me = (MountEntry) {
.path_malloc = TAKE_PTR(prefixed_hierarchy),
- .options_malloc = TAKE_PTR(overlays[i]),
+ .overlay_layers = TAKE_PTR(overlays[i]),
.mode = MOUNT_OVERLAY,
.has_prefix = true,
.ignore = true, /* If the source image doesn't set the ignore bit it will fail earlier. */
}
static int mount_overlay(const MountEntry *m) {
- const char *options;
+ _cleanup_free_ char *options = NULL, *layers = NULL;
int r;
assert(m);
- options = strjoina("lowerdir=", mount_entry_options(m));
+ /* Extension hierarchies are optional (e.g.: confext might not have /opt) so check if they actually
+ * exist in an image before attempting to create an overlay with them, otherwise the mount will
+ * fail. We can't check before this, as the images will not be mounted until now. */
+
+ /* Note that lowerdir= parameters are in 'reverse' order, so the top-most directory in the overlay
+ * comes first in the list. */
+ STRV_FOREACH_BACKWARDS(o, m->overlay_layers) {
+ _cleanup_free_ char *escaped = NULL;
+
+ r = is_dir(*o, /* follow= */ false);
+ if (r <= 0) {
+ if (r != -ENOENT)
+ log_debug_errno(r,
+ "Failed to check whether overlay layer source path '%s' exists, ignoring: %m",
+ *o);
+ continue;
+ }
+
+ escaped = shell_escape(*o, ",:");
+ if (!escaped)
+ return log_oom_debug();
+
+ if (!strextend_with_separator(&layers, ":", escaped))
+ return log_oom_debug();
+ }
+
+ if (!layers) {
+ log_debug("None of the overlays specified in '%s' exist at the source, skipping.",
+ mount_entry_options(m));
+ return 0; /* Only the root is set? Then there's nothing to overlay */
+ }
+
+ options = strjoin("lowerdir=", layers, ":", mount_entry_path(m)); /* The root goes in last */
+ if (!options)
+ return log_oom_debug();
(void) mkdir_p_label(mount_entry_path(m), 0755);
projects / thirdparty / systemd.git / blobdiff