LIBVLC_ERROR=4 /**< Error message */
};
+typedef struct vlc_log_t libvlc_log_t;
+
/**
* Callback prototype for LibVLC log message handler.
- * \param data data pointer as given to libvlc_log_subscribe()
+ * \param data data pointer as given to libvlc_log_set()
* \param level message level (@ref enum libvlc_log_level)
+ * \param ctx message context (meta-informations about the message)
* \param fmt printf() format string (as defined by ISO C11)
* \param args variable argument list for the format
* \note Log message handlers <b>must</b> be thread-safe.
*/
-typedef void (*libvlc_log_cb)(void *data, int level, const char *fmt,
- va_list args);
+typedef void (*libvlc_log_cb)(void *data, int level, const libvlc_log_t *ctx,
+ const char *fmt, va_list args);
/**
- * Data structure for a LibVLC logging callbacks.
- * \note This structure contains exactly 4 pointers and will never change.
- * Nevertheless, it should not be accessed directly outside of LibVLC.
- * (In fact, doing so would fail the thread memory model.)
+ * Unsets the logging callback for a LibVLC instance. This is rarely needed:
+ * the callback is implicitly unset when the instance is destroyed.
+ * This function will wait for any pending callbacks invocation to complete
+ * (causing a deadlock if called from within the callback).
+ *
+ * \version LibVLC 2.1.0 or later
*/
-typedef struct libvlc_log_subscriber
-{
- struct libvlc_log_subscriber *prev, *next;
- libvlc_log_cb func;
- void *opaque;
-} libvlc_log_subscriber_t;
+LIBVLC_API void libvlc_log_unset( libvlc_instance_t * );
/**
- * Registers a logging callback to LibVLC.
- * This function is thread-safe.
+ * Sets the logging callback for a LibVLC instance.
+ * This function is thread-safe: it will wait for any pending callbacks
+ * invocation to complete.
*
- * \param sub uninitialized subscriber structure
* \param cb callback function pointer
* \param data opaque data pointer for the callback function
*
* \note Some log messages (especially debug) are emitted by LibVLC while
- * initializing, before any LibVLC instance even exists.
- * Thus this function does not require a LibVLC instance parameter.
+ * is being initialized. These messages cannot be captured with this interface.
*
- * \warning As a consequence of not depending on a LibVLC instance,
- * all logging callbacks are shared by all LibVLC instances within the
- * process / address space. This also enables log messages to be emitted
- * by LibVLC components that are not specific to any given LibVLC instance.
+ * \warning A deadlock may occur if this function is called from the callback.
*
- * \warning Do not call this function from within a logging callback.
- * It would trigger a dead lock.
* \version LibVLC 2.1.0 or later
*/
-LIBVLC_API void libvlc_log_subscribe( libvlc_log_subscriber_t *sub,
- libvlc_log_cb cb, void *data );
+LIBVLC_API void libvlc_log_set( libvlc_instance_t *,
+ libvlc_log_cb cb, void *data );
/**
- * Registers a logging callback to a file.
+ * Sets up logging to a file.
* \param stream FILE pointer opened for writing
- * (the FILE pointer must remain valid until libvlc_log_unsubscribe())
- * \version LibVLC 2.1.0 or later
- */
-LIBVLC_API void libvlc_log_subscribe_file( libvlc_log_subscriber_t *sub,
- FILE *stream );
-
-/**
- * Deregisters a logging callback from LibVLC.
- * This function is thread-safe.
- *
- * \note After (and only after) libvlc_log_unsubscribe() has returned,
- * LibVLC warrants that there are no more pending calls of the subscription
- * callback function.
- *
- * \warning Do not call this function from within a logging callback.
- * It would trigger a dead lock.
- *
- * \param sub initialized subscriber structure
+ * (the FILE pointer must remain valid until libvlc_log_unset())
* \version LibVLC 2.1.0 or later
*/
-LIBVLC_API void libvlc_log_unsubscribe( libvlc_log_subscriber_t *sub );
+LIBVLC_API void libvlc_log_set_file( libvlc_instance_t *, FILE *stream );
/**
* Always returns minus one.
/*** Logging core dispatcher ***/
-static vlc_rwlock_t log_lock = VLC_STATIC_RWLOCK;
-static libvlc_log_subscriber_t *log_first = NULL;
-static msg_subscription_t sub;
-
-VLC_FORMAT(2,3)
-static void libvlc_log (int level, const char *fmt, ...)
+VLC_FORMAT(4,5)
+static void libvlc_log (libvlc_instance_t *inst, int level,
+ const libvlc_log_t *ctx, const char *fmt, ...)
{
- libvlc_log_subscriber_t *sub;
va_list ap;
- switch (level)
- {
- case VLC_MSG_INFO: level = LIBVLC_NOTICE; break;
- case VLC_MSG_ERR: level = LIBVLC_ERROR; break;
- case VLC_MSG_WARN: level = LIBVLC_WARNING; break;
- case VLC_MSG_DBG: level = LIBVLC_DEBUG; break;
- }
-
va_start (ap, fmt);
- vlc_rwlock_rdlock (&log_lock);
- for (sub = log_first; sub != NULL; sub = sub->next)
- sub->func (sub->opaque, level, fmt, ap);
- vlc_rwlock_unlock (&log_lock);
+ inst->log.cb (inst->log.data, level, ctx, fmt, ap);
va_end (ap);
}
-static void libvlc_logf (void *dummy, int level, const vlc_log_t *item,
+static void libvlc_logf (void *data, int level, const vlc_log_t *item,
const char *fmt, va_list ap)
{
char *msg;
if (unlikely(vasprintf (&msg, fmt, ap) == -1))
- msg = NULL;
+ return;
+
+ switch (level)
+ {
+ case VLC_MSG_INFO: level = LIBVLC_NOTICE; break;
+ case VLC_MSG_ERR: level = LIBVLC_ERROR; break;
+ case VLC_MSG_WARN: level = LIBVLC_WARNING; break;
+ case VLC_MSG_DBG: level = LIBVLC_DEBUG; break;
+ }
+
if (item->psz_header != NULL)
- libvlc_log (level, "[%p] [%s]: %s %s %s", (void *)item->i_object_id,
- item->psz_header, item->psz_module, item->psz_object_type,
- msg ? msg : "Not enough memory");
+ libvlc_log (data, level, item, "[%p] [%s]: %s %s %s",
+ (void *)item->i_object_id, item->psz_header,
+ item->psz_module, item->psz_object_type, msg);
else
- libvlc_log (level, "[%p]: %s %s %s", (void *)item->i_object_id,
- item->psz_module, item->psz_object_type,
- msg ? msg : "Not enough memory");
+ libvlc_log (data, level, item, "[%p]: %s %s %s",
+ (void *)item->i_object_id, item->psz_module,
+ item->psz_object_type, msg);
free (msg);
- (void) dummy;
}
-void libvlc_log_init (void)
+void libvlc_log_unset (libvlc_instance_t *inst)
{
- vlc_Subscribe (&sub, libvlc_logf, NULL);
+ vlc_LogSet (inst->p_libvlc_int, NULL, NULL);
}
-void libvlc_log_deinit (void)
+void libvlc_log_set (libvlc_instance_t *inst, libvlc_log_cb cb, void *data)
{
- vlc_Unsubscribe (&sub);
-}
-
-void libvlc_log_subscribe (libvlc_log_subscriber_t *sub,
- libvlc_log_cb cb, void *data)
-{
- sub->prev = NULL;
- sub->func = cb;
- sub->opaque = data;
- vlc_rwlock_wrlock (&log_lock);
- sub->next = log_first;
- log_first = sub;
- vlc_rwlock_unlock (&log_lock);
-}
-
-void libvlc_log_unsubscribe( libvlc_log_subscriber_t *sub )
-{
- vlc_rwlock_wrlock (&log_lock);
- if (sub->next != NULL)
- sub->next->prev = sub->prev;
- if (sub->prev != NULL)
- sub->prev->next = sub->next;
- else
- log_first = sub->next;
- vlc_rwlock_unlock (&log_lock);
+ libvlc_log_unset (inst); /* <- Barrier before modifying the callback */
+ inst->log.cb = cb;
+ inst->log.data = data;
+ vlc_LogSet (inst->p_libvlc_int, libvlc_logf, inst);
}
/*** Helpers for logging to files ***/
-static void libvlc_log_file (void *data, int level, const char *fmt,
- va_list ap)
+static void libvlc_log_file (void *data, int level, const libvlc_log_t *log,
+ const char *fmt, va_list ap)
{
FILE *stream = data;
vfprintf (stream, fmt, ap);
fputc ('\n', stream);
funlockfile (stream);
- (void) level;
+ (void) level; (void) log;
}
-void libvlc_log_subscribe_file (libvlc_log_subscriber_t *sub, FILE *stream)
+void libvlc_log_set_file (libvlc_instance_t *inst, FILE *stream)
{
- libvlc_log_subscribe (sub, libvlc_log_file, stream);
+ libvlc_log_set (inst, libvlc_log_file, stream);
}
/*** Stubs for the old interface ***/
projects / vlc / commitdiff