cmd/bar/colors: fix dereference of null pointer

`!*rgba` tests if the first byte of rgba isn't `'\0'`.
`hex_to_rgba_hex` returns NULL if `parse_color` fails. There's a null
pointer dereference in that case. The intended behavior is `!rgba`.

1 files changed, 4 insertions, 1 deletions

diff --git a/sway/commands/bar/colors.c b/sway/commands/bar/colors.c
index ea2b912d..2d5b22bf 100644
--- a/sway/commands/bar/colors.c
+++ b/sway/commands/bar/colors.c
@@ -24,6 +24,9 @@ static char *hex_to_rgba_hex(const char *hex) {
                 return NULL;
         }
         char *rgba = malloc(10);
+        if (!rgba) {
+                return NULL;
+        }
         snprintf(rgba, 10, "#%08x", color);
         return rgba;
 }
@@ -36,7 +39,7 @@ static struct cmd_results *parse_single_color(char **color,
         }
 
         char *rgba = hex_to_rgba_hex(argv[0]);
-        if (!*rgba) {
+        if (!rgba) {
                 return cmd_results_new(CMD_INVALID, "Invalid color: %s", argv[0]);
         }