[spotify] Connection handling fixes

src/inputs/librespot-c/src/channel.c

@@ -247,14 +247,14 @@ channel_pause(struct sp_channel *channel)
   channel->state = SP_CHANNEL_STATE_PAUSED;
 }
 
-// After a disconnect we connect to another one and try to resume. To make that
-// work some data elements need to be reset.
+// After a disconnect we connect to another AP and try to resume. To make that
+// work during playback some data elements need to be reset.
 void
 channel_retry(struct sp_channel *channel)
 {
   size_t pos;
 
-  if (!channel)
+  if (!channel || channel->state != SP_CHANNEL_STATE_PLAYING)
     return;
 
   channel->is_data_mode = false;

src/inputs/librespot-c/src/connection.c

@@ -314,6 +314,14 @@ tcp_connection_make(struct sp_connection *conn, struct sp_server *server, struct
   return ret;
 }
 
+static int
+must_resolve(struct sp_server *server)
+{
+  time_t now = time(NULL);
+
+  return (server->last_resolved_ts == 0) || (server->last_failed_ts + SP_AP_AVOID_SECS > now);
+}
+
 void
 ap_disconnect(struct sp_connection *conn)
 {
@@ -329,6 +337,9 @@ ap_connect(struct sp_connection *conn, struct sp_server *server, time_t *cooldow
   int ret;
   time_t now;
 
+  if (must_resolve(server))
+    RETURN_ERROR(SP_ERR_NOCONNECTION, "Cannot connect to access point, it has recently failed");
+
   // Protection against flooding the access points with reconnection attempts
   // Note that cooldown_ts can't be part of the connection struct because
   // the struct is reset between connection attempts.
@@ -549,7 +560,13 @@ prepare_tcp_handshake(struct sp_seq_request *request, struct sp_conn_callbacks *
   if (!session->conn.is_connected)
     {
       ret = ap_connect(&session->conn, &session->accesspoint, &session->cooldown_ts, cb, session);
-      if (ret < 0)
+      if (ret == SP_ERR_NOCONNECTION)
+	{
+	  seq_next_set(session, request->seq_type);
+	  session->request = seq_request_get(SP_SEQ_LOGIN, 0, session->use_legacy);
+	  return SP_OK_WAIT;
+	}
+      else if (ret < 0)
 	RETURN_ERROR(ret, sp_errmsg);
     }
 
@@ -565,8 +582,8 @@ prepare_tcp(struct sp_seq_request *request, struct sp_conn_callbacks *cb, struct
   int ret;
 
   ret = prepare_tcp_handshake(request, cb, session);
-  if (ret < 0)
-    return ret;
+  if (ret != SP_OK_DONE)
+    return ret; // SP_OK_WAIT if the current AP failed and we need to try a new one
 
   if (!session->conn.handshake_completed)
     {
@@ -582,8 +599,6 @@ prepare_tcp(struct sp_seq_request *request, struct sp_conn_callbacks *cb, struct
 
 /* --------------------------- Incoming messages ---------------------------- */
 
-#define SP_AP_RESOLVE_AVOID_SECS 3600
-
 static enum sp_error
 resolve_server_info_set(struct sp_server *server, const char *key, json_object *jresponse)
 {
@@ -597,7 +612,7 @@ resolve_server_info_set(struct sp_server *server, const char *key, json_object *
   int n;
   int i;
 
-  has_failed = (server->last_failed_ts + SP_AP_RESOLVE_AVOID_SECS > time(NULL));
+  has_failed = (server->last_failed_ts + SP_AP_AVOID_SECS > time(NULL));
 
   if (! (json_object_object_get_ex(jresponse, key, &list) || json_object_get_type(list) == json_type_array))
     RETURN_ERROR(SP_ERR_NOCONNECTION, "No address list in response from access point resolver");
@@ -1300,14 +1315,6 @@ msg_tcp_read_one(struct sp_tcp_message *tmsg, struct sp_connection *conn)
 
 /* --------------------------- Outgoing messages ---------------------------- */
 
-static int
-must_resolve(struct sp_server *server)
-{
-  time_t now = time(NULL);
-
-  return (server->last_resolved_ts == 0) || (server->last_failed_ts + SP_AP_RESOLVE_AVOID_SECS > now);
-}
-
 static int
 msg_make_ap_resolve(struct sp_message *msg, struct sp_session *session)
 {

src/inputs/librespot-c/src/crypto.c

@@ -355,6 +355,8 @@ crypto_aes_seek(struct crypto_aes_cipher *cipher, size_t seek, const char **errm
   size_t num_blocks;
   size_t offset;
 
+  assert(cipher->aes);
+
   iv_len = gcry_cipher_get_algo_blklen(GCRY_CIPHER_AES128);
 
   assert(iv_len == sizeof(iv));

src/inputs/librespot-c/src/librespot-c-internal.h

@@ -51,6 +51,9 @@
 // we get the hint and won't try reconnecting again until after this cooldown
 #define SP_AP_COOLDOWN_SECS 30
 
+// How long after a connection failure we try to avoid an AP
+#define SP_AP_AVOID_SECS 3600
+
 // If client hasn't requested anything in particular
 #define SP_BITRATE_DEFAULT SP_BITRATE_320