lib/loopdev: use warn_unused_result forimportant functions

Signed-off-by: Karel Zak <kzak@redhat.com>

1 files changed, 41 insertions, 24 deletions

diff --git a/lib/loopdev.c b/lib/loopdev.c
index 8e5706735..b759f0c28 100644
--- a/lib/loopdev.c
+++ b/lib/loopdev.c
@@ -148,6 +148,7 @@ int loopcxt_has_device(struct loopdev_cxt *lc)
  */
 int loopcxt_init(struct loopdev_cxt *lc, int flags)
 {
+	int rc;
 	struct stat st;
 	struct loopdev_cxt dummy = UL_LOOPDEVCXT_EMPTY;
 
@@ -156,7 +157,10 @@ int loopcxt_init(struct loopdev_cxt *lc, int flags)
 
 	memcpy(lc, &dummy, sizeof(dummy));
 	lc->flags = flags;
-	loopcxt_set_device(lc, NULL);
+
+	rc = loopcxt_set_device(lc, NULL);
+	if (rc)
+		return rc;
 
 	if (!(lc->flags & LOOPDEV_FL_NOSYSFS) &&
 	    get_linux_version() >= KERNEL_VERSION(2,6,37))
@@ -188,7 +192,7 @@ void loopcxt_deinit(struct loopdev_cxt *lc)
 	free(lc->filename);
 	lc->filename = NULL;
 
-	loopcxt_set_device(lc, NULL);
+	ignore_result( loopcxt_set_device(lc, NULL) );
 	loopcxt_deinit_iterator(lc);
 
 	errno = errsv;
@@ -378,8 +382,8 @@ static int loopiter_set_device(struct loopdev_cxt *lc, const char *device)
 	if ((lc->iter.flags & LOOPITER_FL_FREE) && !used)
 		return 0;
 
-	DBG(lc, loopdev_debug("iter: setting device"));
-	loopcxt_set_device(lc, NULL);
+	DBG(lc, loopdev_debug("iter: unset device"));
+	ignore_result( loopcxt_set_device(lc, NULL) );
 	return 1;
 }
 
@@ -1274,27 +1278,29 @@ int loopdev_is_autoclear(const char *device)
 	if (!device)
 		return 0;
 
-	loopcxt_init(&lc, 0);
-	loopcxt_set_device(&lc, device);
-	rc = loopcxt_is_autoclear(&lc);
-	loopcxt_deinit(&lc);
+	rc = loopcxt_init(&lc, 0);
+	if (!rc)
+		rc = loopcxt_set_device(&lc, device);
+	if (!rc)
+		rc = loopcxt_is_autoclear(&lc);
 
+	loopcxt_deinit(&lc);
 	return rc;
 }
 
 char *loopdev_get_backing_file(const char *device)
 {
 	struct loopdev_cxt lc;
-	char *res;
+	char *res = NULL;
 
 	if (!device)
 		return NULL;
+	if (loopcxt_init(&lc, 0))
+		return NULL;
+	if (loopcxt_set_device(&lc, device) == 0)
+		res = loopcxt_get_backing_file(&lc);
 
-	loopcxt_init(&lc, 0);
-	loopcxt_set_device(&lc, device);
-	res = loopcxt_get_backing_file(&lc);
 	loopcxt_deinit(&lc);
-
 	return res;
 }
 
@@ -1311,8 +1317,11 @@ int loopdev_is_used(const char *device, const char *filename,
 	if (!device || !filename)
 		return 0;
 
-	loopcxt_init(&lc, 0);
-	loopcxt_set_device(&lc, device);
+	rc = loopcxt_init(&lc, 0);
+	if (!rc)
+		rc = loopcxt_set_device(&lc, device);
+	if (rc)
+		return rc;
 
 	rc = !stat(filename, &st);
 	rc = loopcxt_is_used(&lc, rc ? &st : NULL, filename, offset, flags);
@@ -1329,8 +1338,9 @@ int loopdev_delete(const char *device)
 	if (!device)
 		return -EINVAL;
 
-	loopcxt_init(&lc, 0);
-	rc = loopcxt_set_device(&lc, device);
+	rc = loopcxt_init(&lc, 0);
+	if (!rc)
+		rc = loopcxt_set_device(&lc, device);
 	if (!rc)
 		rc = loopcxt_delete_device(&lc);
 	loopcxt_deinit(&lc);
@@ -1377,7 +1387,8 @@ char *loopdev_find_by_backing_file(const char *filename, uint64_t offset, int fl
 	if (!filename)
 		return NULL;
 
-	loopcxt_init(&lc, 0);
+	if (loopcxt_init(&lc, 0))
+		return NULL;
 	if (loopcxt_find_by_backing_file(&lc, filename, offset, flags))
 		res = loopcxt_strdup_device(&lc);
 	loopcxt_deinit(&lc);
@@ -1393,12 +1404,14 @@ char *loopdev_find_by_backing_file(const char *filename, uint64_t offset, int fl
 int loopdev_count_by_backing_file(const char *filename, char **loopdev)
 {
 	struct loopdev_cxt lc;
-	int count = 0;
+	int count = 0, rc;
 
 	if (!filename)
 		return -1;
 
-	loopcxt_init(&lc, 0);
+	rc = loopcxt_init(&lc, 0);
+	if (rc)
+		return rc;
 	if (loopcxt_init_iterator(&lc, LOOPITER_FL_USED))
 		return -1;
 
@@ -1436,7 +1449,8 @@ static void test_loop_info(const char *device, int flags, int debug)
 	char *p;
 	uint64_t u64;
 
-	loopcxt_init(&lc, flags);
+	if (loopcxt_init(&lc, flags))
+		return
 	loopcxt_enable_debug(&lc, debug);
 
 	if (loopcxt_set_device(&lc, device))
@@ -1462,7 +1476,8 @@ static void test_loop_scan(int flags, int debug)
 	struct loopdev_cxt lc;
 	int rc;
 
-	loopcxt_init(&lc, 0);
+	if (loopcxt_init(&lc, 0))
+		return;
 	loopcxt_enable_debug(&lc, debug);
 
 	if (loopcxt_init_iterator(&lc, flags))
@@ -1488,9 +1503,11 @@ static void test_loop_scan(int flags, int debug)
 static int test_loop_setup(const char *filename, const char *device, int debug)
 {
 	struct loopdev_cxt lc;
-	int rc = 0;
+	int rc;
 
-	loopcxt_init(&lc, 0);
+	rc = loopcxt_init(&lc, 0);
+	if (rc)
+		return rc;
 	loopcxt_enable_debug(&lc, debug);
 
 	if (device) {