introduce struct condition as a more correct version of Notify

Start using it in the HTTP code

git-svn-id: https://svn.musicpd.org/mpd/trunk@7395 09075e82-0dd4-0310-85a5-a0d7c8717e4f

src/condition.c

@@ -0,0 +1,84 @@
+/* the Music Player Daemon (MPD)
+ * Copyright (C) 2003-2007 by Warren Dukes (warren.dukes@gmail.com)
+ * Copyright (C) 2008 Max Kellermann <max@duempel.org>
+ * This project's homepage is: http://www.musicpd.org
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program 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 General Public License for more details.
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+ */
+
+#include "condition.h"
+#include "utils.h"
+#include "log.h"
+
+void cond_init(struct condition *cond)
+{
+	xpthread_mutex_init(&cond->mutex, NULL);
+	xpthread_cond_init(&cond->cond, NULL);
+}
+
+void cond_enter(struct condition *cond)
+{
+	pthread_mutex_lock(&cond->mutex);
+}
+
+void cond_leave(struct condition *cond)
+{
+	pthread_mutex_unlock(&cond->mutex);
+}
+
+void cond_wait(struct condition *cond)
+{
+	pthread_cond_wait(&cond->cond, &cond->mutex);
+}
+
+static struct timespec * ts_timeout(struct timespec *ts, const long sec)
+{
+	struct timeval tv;
+	gettimeofday(&tv, NULL);
+	ts->tv_sec = tv.tv_sec + sec;
+	ts->tv_nsec = tv.tv_usec * 1000;
+	return ts;
+}
+
+int cond_timedwait(struct condition *cond, const long sec)
+{
+	struct timespec ts;
+	int ret = pthread_cond_timedwait(&cond->cond, &cond->mutex,
+	                                 ts_timeout(&ts, sec));
+	if (!ret || ret == ETIMEDOUT)
+		return ret;
+	FATAL("cond_timedwait: %s\n", strerror(ret));
+	return ret;
+}
+
+int cond_signal_async(struct condition *cond)
+{
+	if (!pthread_mutex_trylock(&cond->mutex)) {
+		pthread_cond_signal(&cond->cond);
+		pthread_mutex_unlock(&cond->mutex);
+		return 0;
+	}
+	return EBUSY;
+}
+
+void cond_signal_sync(struct condition *cond)
+{
+	pthread_cond_signal(&cond->cond);
+}
+
+void cond_destroy(struct condition *cond)
+{
+	xpthread_cond_destroy(&cond->cond);
+	xpthread_mutex_destroy(&cond->mutex);
+}