libvlc_log_*: deprecated and reimplement as compatibility stubs

include/vlc/libvlc.h

@@ -328,74 +328,81 @@ LIBVLC_API unsigned libvlc_get_log_verbosity( const libvlc_instance_t *p_instanc
 LIBVLC_API void libvlc_set_log_verbosity( libvlc_instance_t *p_instance, unsigned level );
 
 /**
- * Open a VLC message log instance.
+ * This function does nothing useful.
+ * It is only provided for backward compatibility.
  *
  * \param p_instance libvlc instance
- * \return log message instance or NULL on error
+ * \return an unique pointer or NULL on error
  */
+LIBVLC_DEPRECATED
 LIBVLC_API libvlc_log_t *libvlc_log_open( libvlc_instance_t *p_instance );
 
 /**
- * Close a VLC message log instance.
+ * Frees memory allocated by libvlc_log_open().
  *
  * \param p_log libvlc log instance or NULL
  */
+LIBVLC_DEPRECATED
 LIBVLC_API void libvlc_log_close( libvlc_log_t *p_log );
 
 /**
- * Returns the number of messages in a log instance.
+ * Always returns zero.
+ * This function is only provided for backward compatibility.
  *
- * \param p_log libvlc log instance or NULL
- * \return number of log messages, 0 if p_log is NULL
+ * \param p_log ignored
+ * \return always zero
  */
+LIBVLC_DEPRECATED
 LIBVLC_API unsigned libvlc_log_count( const libvlc_log_t *p_log );
 
 /**
- * Clear a log instance.
- *
- * All messages in the log are removed. The log should be cleared on a
- * regular basis to avoid clogging.
+ * This function does nothing.
+ * It is only provided for backward compatibility.
  *
- * \param p_log libvlc log instance or NULL
+ * \param p_log ignored
  */
+LIBVLC_DEPRECATED
 LIBVLC_API void libvlc_log_clear( libvlc_log_t *p_log );
 
 /**
- * Allocate and returns a new iterator to messages in log.
+ * This function does nothing useful.
+ * It is only provided for backward compatibility.
  *
- * \param p_log libvlc log instance
- * \return log iterator object or NULL on error
+ * \param p_log ignored
+ * \return an unique pointer or NULL on error or if the parameter was NULL
  */
+LIBVLC_DEPRECATED
 LIBVLC_API libvlc_log_iterator_t *libvlc_log_get_iterator( const libvlc_log_t *p_log );
 
 /**
- * Release a previoulsy allocated iterator.
+ * Frees memory allocated by libvlc_log_get_iterator().
  *
  * \param p_iter libvlc log iterator or NULL
  */
+LIBVLC_DEPRECATED
 LIBVLC_API void libvlc_log_iterator_free( libvlc_log_iterator_t *p_iter );
 
 /**
- * Return whether log iterator has more messages.
+ * Always returns zero.
+ * This function is only provided for backward compatibility.
  *
- * \param p_iter libvlc log iterator or NULL
- * \return true if iterator has more message objects, else false
- *
- * \libvlc_return_bool
+ * \param p_iter ignored
+ * \return always zero
  */
+LIBVLC_DEPRECATED
 LIBVLC_API int libvlc_log_iterator_has_next( const libvlc_log_iterator_t *p_iter );
 
 /**
- * Return the next log message.
- *
- * The message contents must not be freed
+ * Always returns NULL.
+ * This function is only provided for backward compatibility.
  *
  * \param p_iter libvlc log iterator or NULL
- * \param p_buffer log buffer
- * \return log message object or NULL if none left
+ * \param p_buffer ignored
+ * \return always NULL
  */
+LIBVLC_DEPRECATED
 LIBVLC_API libvlc_log_message_t *libvlc_log_iterator_next( libvlc_log_iterator_t *p_iter,
-                                                               libvlc_log_message_t *p_buffer );
+                                                           libvlc_log_message_t *p_buffer );
 
 /** @} */
 

src/control/log.c

@@ -30,51 +30,9 @@
 #include <vlc/libvlc.h>
 #include <assert.h>
 
-/* This API is terminally broken.
- * First, it does not implement any kind of notification.
- * Second, the iterating scheme is hermetic to any kind of thread-safety
- * owing to its constant pointer constraints.
- *  -- Courmisch
- *
- * "If you break your leg, don't run to me for sympathy"
- *   -- some character, Beneath a Steel Sky
- */
-
-typedef struct
-{
-    vlc_spinlock_t lock;
-    msg_item_t *items[VLC_MSG_QSIZE];
-    unsigned    count;
-    int         verbosity;
-} msg_cb_data_t;
-
-static void handler( void *opaque, const msg_item_t *p_item )
-{
-    msg_cb_data_t *d = opaque;
-
-    if (p_item->i_type > d->verbosity)
-        return;
-
-    msg_item_t *msg = msg_Copy (p_item);
-
-    vlc_spin_lock (&d->lock);
-    if (d->count < VLC_MSG_QSIZE)
-        d->items[d->count++] = msg;
-    vlc_spin_unlock (&d->lock);
-}
-
 struct libvlc_log_t
 {
     libvlc_instance_t  *p_instance;
-    msg_subscription_t *p_messages;
-    msg_cb_data_t       data;
-};
-
-struct libvlc_log_iterator_t
-{
-    msg_cb_data_t *p_data;
-    unsigned i_pos;
-    unsigned i_end;
 };
 
 unsigned libvlc_get_log_verbosity( const libvlc_instance_t *p_instance )
@@ -91,95 +49,29 @@ void libvlc_set_log_verbosity( libvlc_instance_t *p_instance, unsigned level )
 
 libvlc_log_t *libvlc_log_open( libvlc_instance_t *p_instance )
 {
-    struct libvlc_log_t *p_log = malloc(sizeof(*p_log));
-    if (unlikely(p_log == NULL))
-    {
-        libvlc_printerr ("Not enough memory");
-        return NULL;
-    }
-
-    p_log->p_instance = p_instance;
-    vlc_spin_init( &p_log->data.lock );
-    p_log->data.count = 0;
-    p_log->data.verbosity = p_instance->verbosity;
-    p_log->p_messages = vlc_Subscribe(handler, &p_log->data);
-
-    if( !p_log->p_messages )
-    {
-        free( p_log );
-        libvlc_printerr ("Not enough memory");
-        return NULL;
-    }
-
-    libvlc_retain( p_instance );
-    return p_log;
+    (void) p_instance;
+    return malloc(1);
 }
 
 void libvlc_log_close( libvlc_log_t *p_log )
 {
-    if( !p_log )
-        return;
-
-    assert( p_log->p_messages );
-    vlc_Unsubscribe(p_log->p_messages);
-    libvlc_release( p_log->p_instance );
-    libvlc_log_clear( p_log );
-    vlc_spin_destroy( &p_log->data.lock );
     free(p_log);
 }
 
 unsigned libvlc_log_count( const libvlc_log_t *p_log )
 {
-    if( !p_log )
-        return 0;
-
-    msg_cb_data_t *data = &((libvlc_log_t *)p_log)->data;
-    unsigned ret;
-
-    /* We cannot lock due to constant pointer constraints. Break them.
-     * Even then, this si not really thread safe anyway. */
-    vlc_spin_lock (&data->lock);
-    ret = data->count;
-    vlc_spin_unlock (&data->lock);
-    return ret;
+    (void) p_log;
+    return 0;
 }
 
 void libvlc_log_clear( libvlc_log_t *p_log )
 {
-    if( !p_log )
-        return;
-
-    vlc_spin_lock (&p_log->data.lock);
-    msg_item_t *tab[p_log->data.count];
-    memcpy (tab, p_log->data.items, sizeof (tab));
-    p_log->data.count = 0;
-    vlc_spin_unlock (&p_log->data.lock);
-
-    for (unsigned i = 0; i < sizeof (tab) / sizeof (tab[0]); i++)
-         msg_Free (tab[i]);
+    (void) p_log;
 }
 
 libvlc_log_iterator_t *libvlc_log_get_iterator( const libvlc_log_t *p_log )
 {
-    if (p_log == NULL)
-        return NULL;
-
-    struct libvlc_log_iterator_t *p_iter = malloc (sizeof (*p_iter));
-    if (unlikely(p_iter == NULL))
-    {
-        libvlc_printerr ("Not enough memory");
-        return NULL;
-    }
-
-    /* FIXME: break constant pointer constraints */
-    msg_cb_data_t *data = &((libvlc_log_t *)p_log)->data;
-
-    vlc_spin_lock (&data->lock);
-    p_iter->p_data  = data;
-    p_iter->i_pos   = 0;
-    p_iter->i_end   = data->count;
-    vlc_spin_unlock (&data->lock);
-    return p_iter;
+    return (p_log != NULL) ? malloc(1) : NULL;
 }
 
 void libvlc_log_iterator_free( libvlc_log_iterator_t *p_iter )
@@ -189,35 +81,13 @@ void libvlc_log_iterator_free( libvlc_log_iterator_t *p_iter )
 
 int libvlc_log_iterator_has_next( const libvlc_log_iterator_t *p_iter )
 {
-    if( !p_iter )
-        return 0;
-    return p_iter->i_pos != p_iter->i_end;
+    (void) p_iter;
+    return 0;
 }
 
 libvlc_log_message_t *libvlc_log_iterator_next( libvlc_log_iterator_t *p_iter,
                                                 libvlc_log_message_t *buffer )
 {
-    unsigned i_pos;
-
-    if( !p_iter )
-        return NULL;
-    assert (buffer != NULL);
-
-    i_pos = p_iter->i_pos;
-    if( i_pos != p_iter->i_end )
-    {
-        msg_item_t *msg;
-        vlc_spin_lock (&p_iter->p_data->lock);
-        msg = p_iter->p_data->items[i_pos];
-        buffer->i_severity  = msg->i_type;
-        buffer->psz_type    = msg->psz_object_type;
-        buffer->psz_name    = msg->psz_module;
-        buffer->psz_header  = msg->psz_header;
-        buffer->psz_message = msg->psz_msg;
-        vlc_spin_unlock (&p_iter->p_data->lock);
-        p_iter->i_pos++;
-
-        return buffer;
-    }
+    (void) p_iter; (void) buffer;
     return NULL;
 }