From 01acc8152487cc5ea54150fec9be3709af6ea0d3 Mon Sep 17 00:00:00 2001
From: Jonas 'Sortie' Termansen <sortie@maxsi.org>
Date: Tue, 17 Sep 2013 00:07:29 +0200
Subject: [PATCH] Add pthread_cond_timedwait(3).

---
 libpthread/Makefile                   |  1 +
 libpthread/include/pthread.h          |  4 +-
 libpthread/pthread_cond_timedwait.c++ | 57 +++++++++++++++++++++++++++
 3 files changed, 61 insertions(+), 1 deletion(-)
 create mode 100644 libpthread/pthread_cond_timedwait.c++

diff --git a/libpthread/Makefile b/libpthread/Makefile
index c8827fcd..9f66af48 100644
--- a/libpthread/Makefile
+++ b/libpthread/Makefile
@@ -13,6 +13,7 @@ CXXFLAGS:=$(CXXFLAGS) -Wall -Wextra -fno-exceptions -fno-rtti
 OBJS=\
 pthread_cond_broadcast.o \
 pthread_cond_signal.o \
+pthread_cond_timedwait.o \
 pthread_cond_wait.o \
 pthread_equal.o \
 pthread_initialize.o \
diff --git a/libpthread/include/pthread.h b/libpthread/include/pthread.h
index d9924a83..8895c833 100644
--- a/libpthread/include/pthread.h
+++ b/libpthread/include/pthread.h
@@ -192,7 +192,9 @@ int pthread_cond_broadcast(pthread_cond_t*);
 /* TODO: pthread_cond_destroy */
 /* TODO: pthread_cond_init */
 int pthread_cond_signal(pthread_cond_t*);
-/* TODO: pthread_cond_timedwait */
+int pthread_cond_timedwait(pthread_cond_t* __restrict,
+                           pthread_mutex_t* __restrict,
+                           const struct timespec* __restrict);
 int pthread_cond_wait(pthread_cond_t* __restrict, pthread_mutex_t* __restrict);
 /* TODO: pthread_condattr_destroy */
 /* TODO: pthread_condattr_getclock */
diff --git a/libpthread/pthread_cond_timedwait.c++ b/libpthread/pthread_cond_timedwait.c++
new file mode 100644
index 00000000..fa96da4f
--- /dev/null
+++ b/libpthread/pthread_cond_timedwait.c++
@@ -0,0 +1,57 @@
+/*******************************************************************************
+
+    Copyright(C) Jonas 'Sortie' Termansen 2014.
+
+    This file is part of Sortix libpthread.
+
+    Sortix libpthread is free software: you can redistribute it and/or modify it
+    under the terms of the GNU Lesser General Public License as published by the
+    Free Software Foundation, either version 3 of the License, or (at your
+    option) any later version.
+
+    Sortix libpthread 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 Lesser General Public
+    License for more details.
+
+    You should have received a copy of the GNU Lesser General Public License
+    along with Sortix libpthread. If not, see <http://www.gnu.org/licenses/>.
+
+    pthread_cond_timedwait.c++
+    Waits on a condition or until a timeout happens.
+
+*******************************************************************************/
+
+#include <errno.h>
+#include <pthread.h>
+#include <sched.h>
+#include <time.h>
+#include <timespec.h>
+#include <unistd.h>
+
+extern "C"
+int pthread_cond_timedwait(pthread_cond_t* restrict cond,
+                           pthread_mutex_t* restrict mutex,
+                           const struct timespec* restrict abstime)
+{
+	struct pthread_cond_elem elem;
+	elem.next = NULL;
+	elem.woken = 0;
+	if ( cond->last )
+		cond->last->next = &elem;
+	if ( !cond->last )
+		cond->first = &elem;
+	cond->last = &elem;
+	while ( !elem.woken )
+	{
+		struct timespec now;
+		if ( clock_gettime(CLOCK_REALTIME, &now) < 0 )
+			return errno;
+		if ( timespec_le(*abstime, now) )
+			return errno = ETIMEDOUT;
+		pthread_mutex_unlock(mutex);
+		sched_yield();
+		pthread_mutex_lock(mutex);
+	}
+	return 0;
+}