sway

commit e362f871d93df7568267d9a50ff77b63f5300528
parent 9fb020d04c487904ef3d87a15bbdc885cca886e7
Author: Christoph Gysin <christoph.gysin@gmail.com>
Date:   Wed, 25 Nov 2015 23:19:08 +0200

Call swaybg without invoking a shell

This makes escaping the arguments obsolete.

Also avoid dynamic memory allocation for the output id. It only supported ids up
to 99. Now we support up to 999, and take 4 bytes off the stack instead.

Diffstat:
M
sway/config.c
 | 
23
++++++++++++++---------

1 file changed, 14 insertions(+), 9 deletions(-)
diff --git a/sway/config.c b/sway/config.c
@@ -334,17 +334,22 @@ void apply_output_config(struct output_config *oc, swayc_t *output) {
 		}
 
 		sway_log(L_DEBUG, "Setting background for output %d to %s", i, oc->background);
-		char *cmd = malloc(
-				strlen("swaybg ") +
-				(i >= 10 ? 2 : 1) +
-				strlen(oc->background) + 3 +
-				strlen(oc->background_option) + 3 +
-				1);
-		sprintf(cmd, "swaybg %d '%s' '%s'", i, oc->background, oc->background_option);
+
+		size_t bufsize = 4;
+		char output_id[bufsize];
+		snprintf(output_id, bufsize, "%d", i);
+		output_id[bufsize-1] = 0;
+
+		char *const cmd[] = {
+			"swaybg",
+			output_id,
+			oc->background,
+			oc->background_option,
+			NULL,
+		};
 		if (fork() == 0) {
-			execl("/bin/sh", "/bin/sh", "-c", cmd, (void *)NULL);
+			execvp(cmd[0], cmd);
 		}
-		free(cmd);
 	}
 }