images: Implement collect_images() to minimaze code lines

Pack repeated actions in one. Also, fixed the "return -1"
from the middle of restore_task_with_children(),
while cleanup is need.

v2: goto err in case of error instead of return -1.
Signed-off-by: Kirill Tkhai <ktkhai@virtuozzo.com>
Signed-off-by: Andrei Vagin <avagin@virtuozzo.com>

criu/cr-restore.c

@@ -320,7 +320,7 @@ static int run_post_prepare(void)
 
 static int root_prepare_shared(void)
 {
-	int ret = 0, i;
+	int ret = 0;
 	struct pstree_item *pi;
 
 	pr_info("Preparing info about shared resources\n");
@@ -331,11 +331,8 @@ static int root_prepare_shared(void)
 	if (prepare_seccomp_filters())
 		return -1;
 
-	for (i = 0; i < ARRAY_SIZE(cinfos); i++) {
-		ret = collect_image(cinfos[i]);
-		if (ret)
-			return -1;
-	}
+	if (collect_images(cinfos, ARRAY_SIZE(cinfos)))
+		return -1;
 
 	for_each_pstree_item(pi) {
 		if (pi->pid->state == TASK_HELPER)
@@ -1505,8 +1502,6 @@ static int restore_task_with_children(void *_arg)
 
 	/* Restore root task */
 	if (current->parent == NULL) {
-		int i;
-
 		if (fdstore_init())
 			goto err;
 
@@ -1526,12 +1521,8 @@ static int restore_task_with_children(void *_arg)
 		if (mount_proc())
 			goto err;
 
-		for (i = 0; i < ARRAY_SIZE(before_ns_cinfos); i++) {
-			ret = collect_image(before_ns_cinfos[i]);
-			if (ret)
-				return -1;
-		}
-
+		if (collect_images(before_ns_cinfos, ARRAY_SIZE(before_ns_cinfos)))
+			goto err;
 
 		if (prepare_namespace(current, ca->clone_flags))
 			goto err;

criu/include/protobuf.h

@@ -41,4 +41,14 @@ struct collect_image_info {
 
 extern int collect_image(struct collect_image_info *);
 
+static inline int collect_images(struct collect_image_info **array, unsigned size)
+{
+	int i;
+	for (i = 0; i < size; i++) {
+		if (collect_image(array[i]))
+			return -1;
+	}
+	return 0;
+}
+
 #endif /* __CR_PROTOBUF_H__ */