spoon

commit cac2ac13bd99c53ca562157a99befd92ad643a1d
parent 89d58af7a14ee86a7d44d01c069d60fc7307f84f
Author: lostd <lostd@2f30.org>
Date:   Sun, 20 Nov 2016 13:18:21 +0000

Fix null pointer dereference in status

Also make checking if the connection is alive more robust
and consistent.

Diffstat:
M
mpd.c
 | 
27
+++++++++++++++++----------

1 file changed, 17 insertions(+), 10 deletions(-)
diff --git a/mpd.c b/mpd.c
@@ -25,27 +25,36 @@ mpdread(void *arg, char *buf, size_t len)
 	struct mpdarg *mpdarg = arg;
 	static int frame = 0;
 
+#define CHECK_CONNECTION(conn) \
+	if (mpd_connection_get_error(conn) != MPD_ERROR_SUCCESS) { \
+		warnx("mpd_connection_get_error: %s", \
+		      mpd_connection_get_error_message(conn)); \
+		goto out; \
+	}
+
 	if (conn == NULL) {
 		conn = mpd_connection_new(mpdarg->host, mpdarg->port, 0);
 		if (conn == NULL)
 			return -1;
-		if (mpd_connection_get_error(conn) != MPD_ERROR_SUCCESS)
-			goto out;
+		CHECK_CONNECTION(conn);
 	}
 	mpd_send_status(conn);
 	status = mpd_recv_status(conn);
+	if (status == NULL) {
+		CHECK_CONNECTION(conn);
+		mpd_response_finish(conn);
+		return -1;
+	}
 	state = mpd_status_get_state(status);
 	mpd_status_free(status);
-	if (!mpd_response_finish(conn))
-		goto out;
+	mpd_response_finish(conn);
 	if (state != MPD_STATE_PLAY && state != MPD_STATE_PAUSE)
 		return -1;
 	mpd_send_current_song(conn);
 	song = mpd_recv_song(conn);
 	if (song == NULL) {
-		if (mpd_connection_get_error(conn) != MPD_ERROR_SUCCESS)
-			goto out;
-		/* if no song is playing, reuse connection next time */
+		CHECK_CONNECTION(conn);
+		mpd_response_finish(conn);
 		return -1;
 	}
 	artist = mpd_song_get_tag(song, MPD_TAG_ARTIST, 0);
@@ -58,11 +67,9 @@ mpdread(void *arg, char *buf, size_t len)
 		strlcpy(buf, anim[frame++ % LEN(anim)], len);
 	}
 	mpd_song_free(song);
-	if (!mpd_response_finish(conn))
-		goto out;
+	mpd_response_finish(conn);
 	return 0;
 out:
-	warnx("failed to talk to mpd");
 	mpd_connection_free(conn);
 	conn = NULL;
 	return -1;