autofs-5.1.7 - eliminate some strlen calls in offset handling

From: Ian Kent <raven@themaw.net>

There are a number of places where strlen() is used to re-calculate

the length of a string. Eliminate some of those by calculating the

length once and passing it to the functions that do the re-calculation.

Signed-off-by: Ian Kent <raven@themaw.net>

---

 CHANGELOG    |    1 +

 lib/mounts.c |   30 +++++++++++++++++-------------

 2 files changed, 18 insertions(+), 13 deletions(-)

diff --git a/CHANGELOG b/CHANGELOG

index 0b78eb62..cb709773 100644

--- a/CHANGELOG

+++ b/CHANGELOG

@@ -21,6 +21,7 @@

 - fix inconsistent locking in parse_mount().

 - remove unused mount offset list lock functions.

 - eliminate count_mounts() from expire_proc_indirect().

+- eliminate some strlen calls in offset handling.

 25/01/2021 autofs-5.1.7

 - make bind mounts propagation slave by default.

diff --git a/lib/mounts.c b/lib/mounts.c

index 0fcd4087..04fe3d00 100644

--- a/lib/mounts.c

+++ b/lib/mounts.c

@@ -2540,10 +2540,12 @@ static int rmdir_path_offset(struct autofs_point *ap, struct mapent *oe)

 	return ret;

 }

-static int do_umount_offset(struct autofs_point *ap, struct mapent *oe, const char *root);

+static int do_umount_offset(struct autofs_point *ap,

+			    struct mapent *oe, const char *root, int start);

 static int do_umount_multi_triggers(struct autofs_point *ap,

-				    struct mapent *me, const char *root, const char *base)

+				    struct mapent *me, const char *root,

+				    int start, const char *base)

 {

 	char path[PATH_MAX + 1];

 	char *offset;

@@ -2551,12 +2553,11 @@ static int do_umount_multi_triggers(struct autofs_point *ap,

 	struct list_head *mm_root, *pos;

 	const char o_root[] = "/";

 	const char *mm_base;

-	int left, start;

+	int left;

 	unsigned int root_len;

 	unsigned int mm_base_len;

 	left = 0;

-	start = strlen(root);

 	mm_root = &me->multi->multi_list;

@@ -2592,13 +2593,14 @@ static int do_umount_multi_triggers(struct autofs_point *ap,

 		if (!oe || (strlen(oe->key) - start) == 1)

 			continue;

-		left += do_umount_offset(ap, oe, root);

+		left += do_umount_offset(ap, oe, root, start);

 	}

 	return left;

 }

-static int do_umount_offset(struct autofs_point *ap, struct mapent *oe, const char *root)

+static int do_umount_offset(struct autofs_point *ap,

+			    struct mapent *oe, const char *root, int start)

 {

 	char *oe_base;

 	int left = 0;

@@ -2607,8 +2609,8 @@ static int do_umount_offset(struct autofs_point *ap, struct mapent *oe, const ch

 	 * Check for and umount subtree offsets resulting from

 	 * nonstrict mount fail.

 	 */

-	oe_base = oe->key + strlen(root);

-	left += do_umount_multi_triggers(ap, oe, root, oe_base);

+	oe_base = oe->key + start;

+	left += do_umount_multi_triggers(ap, oe, root, start, oe_base);

 	/*

 	 * If an offset that has an active mount has been removed

@@ -2712,7 +2714,7 @@ int mount_multi_triggers(struct autofs_point *ap, struct mapent *me,

 			goto cont;

 		if (oe->age != me->multi->age) {

 			/* Best effort */

-			do_umount_offset(ap, oe, root);

+			do_umount_offset(ap, oe, root, start);

 			goto cont;

 		}

@@ -2726,7 +2728,7 @@ int mount_multi_triggers(struct autofs_point *ap, struct mapent *me,

 		if (ap->state == ST_READMAP && ap->flags & MOUNT_FLAG_REMOUNT) {

 			if (oe->ioctlfd != -1 ||

 			    is_mounted(oe->key, MNTS_REAL))

-				mount_multi_triggers(ap, oe, key, strlen(key), base);

+				mount_multi_triggers(ap, oe, key, key_len, base);

 		}

 cont:

 		offset = cache_get_offset(base,

@@ -2738,9 +2740,11 @@ cont:

 int umount_multi_triggers(struct autofs_point *ap, struct mapent *me, char *root, const char *base)

 {

-	int left;

+	int left, start;

+

+	start = strlen(root);

-	left = do_umount_multi_triggers(ap, me, root, base);

+	left = do_umount_multi_triggers(ap, me, root, start, base);

 	if (!left && me->multi == me) {

 		/*

@@ -2753,7 +2757,7 @@ int umount_multi_triggers(struct autofs_point *ap, struct mapent *me, char *root

 			info(ap->logopt, "unmounting dir = %s", root);

 			if (umount_ent(ap, root) &&

 			    is_mounted(root, MNTS_REAL)) {

-				if (mount_multi_triggers(ap, me, root, strlen(root), "/") < 0)

+				if (mount_multi_triggers(ap, me, root, start, "/") < 0)

 					warn(ap->logopt,

 					     "failed to remount offset triggers");

 				return ++left;