screenshooter: fix various memory handling

There were unchecked malloc and no free for this memory.
Also simplify error handling in one function.

v2. remove check if memory is NULL, according to man pages,
    free(NULL) is a no-op

Signed-off-by: Marek Chalupa <mchqwerty@gmail.com>
Reviewed-by: Pekka Paalanen <pekka.paalanen@collabora.co.uk>

src/screenshooter.c

@@ -464,8 +464,9 @@ weston_recorder_free(struct weston_recorder *recorder)
 {
 	if (recorder == NULL)
 		return;
-	free(recorder->rect);
+
 	free(recorder->tmpbuf);
+	free(recorder->rect);
 	free(recorder->frame);
 	free(recorder);
 }
@@ -495,12 +496,16 @@ weston_recorder_create(struct weston_output *output, const char *filename)
 
 	if ((recorder->frame == NULL) || (recorder->rect == NULL)) {
 		weston_log("%s: out of memory\n", __func__);
-		weston_recorder_free(recorder);
-		return;
+		goto err_recorder;
 	}
 
-	if (!do_yflip)
+	if (!do_yflip) {
 		recorder->tmpbuf = malloc(size);
+		if (recorder->tmpbuf == NULL) {
+			weston_log("%s: out of memory\n", __func__);
+			goto err_recorder;
+		}
+	}
 
 	header.magic = WCAP_HEADER_MAGIC;
 
@@ -514,8 +519,7 @@ weston_recorder_create(struct weston_output *output, const char *filename)
 		break;
 	default:
 		weston_log("unknown recorder format\n");
-		weston_recorder_free(recorder);
-		return;
+		goto err_recorder;
 	}
 
 	recorder->fd = open(filename,
@@ -523,8 +527,7 @@ weston_recorder_create(struct weston_output *output, const char *filename)
 
 	if (recorder->fd < 0) {
 		weston_log("problem opening output file %s: %m\n", filename);
-		weston_recorder_free(recorder);
-		return;
+		goto err_recorder;
 	}
 
 	header.width = output->current_mode->width;
@@ -535,6 +538,12 @@ weston_recorder_create(struct weston_output *output, const char *filename)
 	wl_signal_add(&output->frame_signal, &recorder->frame_listener);
 	output->disable_planes++;
 	weston_output_damage(output);
+
+	return;
+
+err_recorder:
+	weston_recorder_free(recorder);
+	return;
 }
 
 static void