A poor mans clock...

Original commit message from CVS:
A poor mans clock...

gst/gstclock.c

+/* Gnome-Streamer
+ * Copyright (C) <1999> Erik Walthinsen <omega@cse.ogi.edu>
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Library General Public
+ * License as published by the Free Software Foundation; either
+ * version 2 of the License, or (at your option) any later version.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Library General Public License for more details.
+ *
+ * You should have received a copy of the GNU Library General Public
+ * License along with this library; if not, write to the
+ * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
+ * Boston, MA 02111-1307, USA.
+ */
+
+#include <sys/time.h>
+#define DEBUG_ENABLED
+#include <gstclock.h>
+
+static GstClock *the_system_clock = NULL;
+static int num;
+
+/**
+ * gst_clock_new:
+ * @name: the name of the new clock
+ *
+ * create a new clock element
+ *
+ * Returns: the new clock element
+ */
+GstClock *gst_clock_new(gchar *name) {
+  GstClock *clock = (GstClock *) g_malloc(sizeof(GstClock));
+  clock->name = g_strdup(name);
+  clock->sinkobjects = NULL;
+  clock->sinkmutex = g_mutex_new();
+  clock->lock = g_mutex_new();
+  g_mutex_lock(clock->sinkmutex);
+  num =0;
+  clock->locking = TRUE;
+  return clock;
+}
+
+GstClock *gst_clock_get_system() {
+  if (the_system_clock == NULL) {
+    the_system_clock = gst_clock_new("system_clock");
+    gst_clock_reset(the_system_clock);
+  }
+  return the_system_clock;
+}
+
+void gst_clock_register(GstClock *clock, GstObject *obj) {
+  if (GST_IS_SINK(obj)) {
+    DEBUG("gst_clock: registered sink object 0x%p\n", obj);
+    clock->sinkobjects = g_list_append(clock->sinkobjects, obj);
+    num++;
+  }
+}
+
+void gst_clock_set(GstClock *clock, GstClockTime time) {
+  struct timeval tfnow;
+  GstClockTime target, now;
+
+  g_mutex_lock(clock->lock);
+  gettimeofday(&tfnow, (struct timezone *)NULL);
+  now = tfnow.tv_sec*1000000+tfnow.tv_usec;
+  clock->adjust = now - (clock->start_time + time);
+  clock->current_time = (clock->start_time + time);
+  //DEBUG("gst_clock: setting clock to %llu %llu %lld\n", (guint64)clock->start_time+time, (guint64)now, (gint64)clock->adjust);
+  g_mutex_unlock(clock->lock);
+}
+
+void gst_clock_reset(GstClock *clock) {
+  struct timeval tfnow;
+
+  gettimeofday(&tfnow, (struct timezone *)NULL);
+  clock->start_time = tfnow.tv_sec*1000000+tfnow.tv_usec;
+  clock->current_time = clock->start_time;
+  clock->adjust = 0LL;
+  DEBUG("gst_clock: setting start clock %llu\n", clock->start_time);
+}
+
+void gst_clock_wait(GstClock *clock, GstClockTime time, GstObject *obj) {
+  struct timeval tfnow;
+  GstClockTime target, now;
+  GstClockTimeDiff diff;
+  GList *elements;
+
+  g_mutex_lock(clock->lock);
+  elements = clock->sinkobjects;
+  while (elements && clock->locking) {
+    if (elements->data == obj) {
+      DEBUG("gst_clock: registered sink object 0x%p\n", obj);
+      num--;
+      if (num) {
+        DEBUG("gst_clock: 0x%p locked\n", obj);
+        g_mutex_unlock(clock->lock);
+        g_mutex_lock(clock->sinkmutex);
+        g_mutex_lock(clock->lock);
+	clock->locking = FALSE;
+      }
+      else {
+        DEBUG("gst_clock: unlock all %p\n", obj);
+	gst_clock_reset(clock);
+        g_mutex_unlock(clock->sinkmutex);
+	clock->locking = FALSE;
+      }
+      break;
+    }
+    elements = g_list_next(elements);
+  }
+
+  target = clock->start_time + time;
+  gettimeofday(&tfnow, (struct timezone *)NULL);
+  now = tfnow.tv_sec*1000000+tfnow.tv_usec + clock->adjust;
+  //now = clock->current_time + clock->adjust;
+
+  //DEBUG("gst_clock: 0x%p waiting for time %llu %llu\n", obj, time, target);
+
+  diff = GST_CLOCK_DIFF(target, now);
+  // if we are not behind wait a bit
+   
+  if (diff > 1000 ) {
+    tfnow.tv_usec = diff % 1000000;
+    tfnow.tv_sec = diff / 1000000;
+    // FIXME, this piece of code does not work with egcs optimisations on, had to use the following line
+    if (tfnow.tv_sec) fprintf(stderr, "gst_clock: waiting %u %llu %llu %llu seconds\n", (int)tfnow.tv_sec, now, diff, target);
+    g_mutex_unlock(clock->lock);
+    //DEBUG("gst_clock: 0x%p waiting for time %llu %llu %lld %llu\n", obj, time, target, diff, now);
+    select(0, NULL, NULL, NULL, &tfnow);
+    //DEBUG("gst_clock: 0x%p waiting done time %llu %llu\n", obj, time, target);
+    g_mutex_lock(clock->lock);
+  }
+ // clock->current_time = clock->start_time + time;
+  g_mutex_unlock(clock->lock);
+  //gst_clock_set(clock, time);
+
+}

gst/gstclock.h

+/* Gnome-Streamer
+ * Copyright (C) <1999> Erik Walthinsen <omega@cse.ogi.edu>
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Library General Public
+ * License as published by the Free Software Foundation; either
+ * version 2 of the License, or (at your option) any later version.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Library General Public License for more details.
+ *
+ * You should have received a copy of the GNU Library General Public
+ * License along with this library; if not, write to the
+ * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
+ * Boston, MA 02111-1307, USA.
+ */
+
+
+#ifndef __GST_CLOCK_H__
+#define __GST_CLOCK_H__
+
+
+#include <gst/gst.h>
+
+#ifdef __cplusplus
+extern "C" {
+#endif /* __cplusplus */
+
+
+typedef guint64 GstClockTime;
+typedef gint64 GstClockTimeDiff;
+
+#define GST_CLOCK_DIFF(s, e) (GstClockTimeDiff)((s)-(e))
+
+typedef struct _GstClock GstClock;
+
+struct _GstClock {
+  gchar *name;
+  GstClockTime start_time;
+  GstClockTime current_time;
+  GstClockTimeDiff adjust;
+  gboolean locking;
+  GList *sinkobjects;
+  GMutex *sinkmutex;
+  GMutex *lock;
+};
+
+GstClock *gst_clock_new(gchar *name);
+GstClock *gst_clock_get_system(void);
+
+void gst_clock_register(GstClock *clock, GstObject *obj);
+void gst_clock_set(GstClock *clock, GstClockTime time);
+void gst_clock_reset(GstClock *clock);
+void gst_clock_wait(GstClock *clock, GstClockTime time, GstObject *obj);
+
+#ifdef __cplusplus
+}
+#endif /* __cplusplus */
+
+
+#endif /* __GST_CLOCK_H__ */