core: let partial serial responses be consumed by the handlers

src/mm-at-serial-port.c

@@ -85,7 +85,7 @@ parse_response (MMSerialPort *port, GByteArray *response, GError **error)
     return found;
 }
 
-static void
+static gsize
 handle_response (MMSerialPort *port,
                  GByteArray *response,
                  GError *error,
@@ -101,6 +101,8 @@ handle_response (MMSerialPort *port,
     g_string_append_len (string, (const char *) response->data, response->len);
     response_callback (self, string, error, callback_data);
     g_string_free (string, TRUE);
+
+    return response->len;
 }
 
 /*****************************************************************************/

src/mm-qcdm-serial-port.c

@@ -53,7 +53,7 @@ parse_response (MMSerialPort *port, GByteArray *response, GError **error)
     return FALSE;
 }
 
-static void
+static gsize
 handle_response (MMSerialPort *port,
                  GByteArray *response,
                  GError *error,
@@ -62,18 +62,34 @@ handle_response (MMSerialPort *port,
 {
     MMQcdmSerialResponseFn response_callback = (MMQcdmSerialResponseFn) callback;
     GByteArray *unescaped = NULL;
-    gboolean escaping = FALSE;
     GError *dm_error = NULL;
+    gsize used = 0;
+
+    /* Ignore empty frames */
+    if (!response->len > 0 && response->data[0] == 0x7E)
+        return 1;
 
     if (!error) {
-        unescaped = g_byte_array_sized_new (response->len);
-        unescaped->len = dm_unescape ((const char *) response->data, response->len,
-                                      (char *) unescaped->data, unescaped->len,
-                                      &escaping);
-        if (unescaped->len == 0) {
+        gboolean more = FALSE, success;
+
+        /* FIXME: don't munge around with byte array internals */
+        unescaped = g_byte_array_sized_new (1024);
+        success = dm_decapsulate_buffer ((const char *) response->data,
+                                         response->len,
+                                         (char *) unescaped->data,
+                                         sizeof (1024),
+                                         &unescaped->len,
+                                         &used,
+                                         &more);
+        if (!success) {
             g_set_error_literal (&dm_error, 0, 0, "Failed to unescape QCDM packet.");
             g_byte_array_free (unescaped, TRUE);
             unescaped = NULL;
+        } else if (more) {
+            /* Need more data; we shouldn't have gotten here since the parse
+             * function checks for the end-of-frame marker, but whatever.
+             */
+            return 0;
         }
     }
 
@@ -84,6 +100,8 @@ handle_response (MMSerialPort *port,
 
     if (unescaped)
         g_byte_array_free (unescaped, TRUE);
+
+    return used;
 }
 
 /*****************************************************************************/

src/mm-serial-port.c

@@ -492,7 +492,7 @@ mm_serial_port_schedule_queue_process (MMSerialPort *self)
     g_source_unref (source);
 }
 
-static void
+static gsize
 real_handle_response (MMSerialPort *self,
                       GByteArray *response,
                       GError *error,
@@ -502,6 +502,7 @@ real_handle_response (MMSerialPort *self,
     MMSerialResponseFn response_callback = (MMSerialResponseFn) callback;
 
     response_callback (self, response, error, callback_data);
+    return response->len;
 }
 
 static void
@@ -509,6 +510,7 @@ mm_serial_port_got_response (MMSerialPort *self, GError *error)
 {
     MMSerialPortPrivate *priv = MM_SERIAL_PORT_GET_PRIVATE (self);
     MMQueueData *info;
+    gsize consumed = priv->response->len;
 
     if (priv->timeout_id) {
         g_source_remove (priv->timeout_id);
@@ -522,7 +524,7 @@ mm_serial_port_got_response (MMSerialPort *self, GError *error)
 
         if (info->callback) {
             g_warn_if_fail (MM_SERIAL_PORT_GET_CLASS (self)->handle_response != NULL);
-            MM_SERIAL_PORT_GET_CLASS (self)->handle_response (self,
+            consumed = MM_SERIAL_PORT_GET_CLASS (self)->handle_response (self,
                                                                          priv->response,
                                                                          error,
                                                                          info->callback,
@@ -536,8 +538,8 @@ mm_serial_port_got_response (MMSerialPort *self, GError *error)
     if (error)
         g_error_free (error);
 
-    if (priv->response->len)
-        g_byte_array_remove_range (priv->response, 0, priv->response->len);
+    if (consumed)
+        g_byte_array_remove_range (priv->response, 0, consumed);
     if (!g_queue_is_empty (priv->queue))
         mm_serial_port_schedule_queue_process (self);
 }

src/mm-serial-port.h

@@ -74,9 +74,10 @@ struct _MMSerialPortClass {
                                    GError **error);
 
     /* Called after parsing to allow the command response to be delivered to
-     * it's callback to be handled.
+     * it's callback to be handled.  Returns the # of bytes of the response
+     * consumed.
      */
-    void     (*handle_response)   (MMSerialPort *self,
+    gsize     (*handle_response)  (MMSerialPort *self,
                                    GByteArray *response,
                                    GError *error,
                                    GCallback callback,