Merge pull request #3587 from RedSoxFan/fix-background-missing-file

output_cmd_background: fix no file + valid mode

1 files changed, 3 insertions, 0 deletions

diff --git a/common/stringop.c b/common/stringop.c
index 8af0d60f..709be684 100644
--- a/common/stringop.c
+++ b/common/stringop.c
@@ -258,6 +258,9 @@ int unescape_string(char *string) {
 }
 
 char *join_args(char **argv, int argc) {
+        if (!sway_assert(argc > 0, "argc should be positive")) {
+                return NULL;
+        }
         int len = 0, i;
         for (i = 0; i < argc; ++i) {
                 len += strlen(argv[i]) + 1;