[lxc-devel] [PATCH 1/1] fix lxc.mount.auto clearing

[Serge Hallyn]

the way config_mount was structured, sending 'lxc.mount.auto = '
ended up actually clearing all lxc.mount.entrys.  Fix that by
moving the check for an empty value to after the subkey checks.
Then, actually do the clearing of auto_mounts in config_mount_auto.

The 'strlen(subkey)' check being removed was bogus - the subkey
either known to be 'lxc.mount.entry', else subkey would have been
NULL (and forced a return in the block above).

This would have been clearer if the config_mount() and helper
fns were structured like the rest of confile.c.  It's tempting
to switch it over, but there are subtleties in there so it's
not something to do without a lot of thought and testing.

Signed-off-by: Serge Hallyn <serge.hallyn at ubuntu.com>
---
 src/lxc/confile.c | 22 +++++++++++++++-------
 1 file changed, 15 insertions(+), 7 deletions(-)

diff --git a/src/lxc/confile.c b/src/lxc/confile.c
index 0722a37..09eb94d 100644
--- a/src/lxc/confile.c
+++ b/src/lxc/confile.c
@@ -1403,6 +1403,8 @@ out:
 static int config_fstab(const char *key, const char *value,
 			struct lxc_conf *lxc_conf)
 {
+	if (!value || strlen(value) == 0)
+		return -1;
 	return config_path_item(&lxc_conf->fstab, value);
 }
 
@@ -1434,8 +1436,10 @@ static int config_mount_auto(const char *key, const char *value,
 	int i;
 	int ret = -1;
 
-	if (!strlen(value))
-		return -1;
+	if (!value || strlen(value) == 0) {
+		lxc_conf->auto_mounts = 0;
+		return 0;
+	}
 
 	autos = strdup(value);
 	if (!autos) {
@@ -1469,6 +1473,12 @@ static int config_mount_auto(const char *key, const char *value,
 	return ret;
 }
 
+/*
+ * TODO
+ * This fn is handling lxc.mount, lxc.mount.entry, and lxc.mount.auto.
+ * It should probably be split into 3 separate functions indexed by
+ * the config[] entries at top.
+ */
 static int config_mount(const char *key, const char *value,
 			struct lxc_conf *lxc_conf)
 {
@@ -1479,9 +1489,6 @@ static int config_mount(const char *key, const char *value,
 	char *mntelem;
 	struct lxc_list *mntlist;
 
-	if (!value || strlen(value) == 0)
-		return lxc_clear_mount_entries(lxc_conf);
-
 	subkey = strstr(key, token);
 
 	if (!subkey) {
@@ -1499,8 +1506,9 @@ static int config_mount(const char *key, const char *value,
 		return config_mount_auto(key, value, lxc_conf);
 	}
 
-	if (!strlen(subkey))
-		return -1;
+	/* At this point we definately have key = lxc.mount.entry */
+	if (!value || strlen(value) == 0)
+		return lxc_clear_mount_entries(lxc_conf);
 
 	mntlist = malloc(sizeof(*mntlist));
 	if (!mntlist)
-- 
2.1.0