ext: Add more helpers to mess with external resources.

Signed-off-by: Pavel Emelyanov <xemul@virtuozzo.com>

criu/external.c

@@ -40,3 +40,22 @@ char *external_lookup_by_key(char *key)
 	return NULL;
 }
 
+int external_for_each_type(char *type, int (*cb)(struct external *, void *), void *arg)
+{
+	struct external *ext;
+	int ln = strlen(type);
+	int ret = 0;
+
+	list_for_each_entry(ext, &opts.external, node) {
+		if (strncmp(ext->id, type, ln))
+			continue;
+		if (ext->id[ln] != '[')
+			continue;
+
+		ret = cb(ext, arg);
+		if (ret)
+			break;
+	}
+
+	return ret;
+}

criu/include/external.h

@@ -8,4 +8,19 @@ struct external {
 extern int add_external(char *key);
 extern bool external_lookup_id(char *id);
 extern char *external_lookup_by_key(char *id);
+extern int external_for_each_type(char *type, int (*cb)(struct external *, void *), void *arg);
+
+static inline char *external_val(struct external *e)
+{
+	char *aux;
+
+	aux = strchr(e->id, '[');
+	if (aux) {
+		aux = strchr(aux + 1, ']');
+		if (aux && aux[1] == ':')
+			return aux + 2;
+	}
+
+	return NULL;
+}
 #endif