initial checkin

Check in contents of upstream 1.4.2 tarball, exclude generated files.

1 files changed, 76 insertions, 0 deletions

diff --git a/src/threads/sema.cpp b/src/threads/sema.cpp
new file mode 100644
index 0000000..8eb686b
--- /dev/null
+++ b/src/threads/sema.cpp
@@ -0,0 +1,76 @@
+/*
+    Copyright (C) 2005-2009  Michel de Boer <michel@twinklephone.com>
+
+    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 <cerrno>
+#include <cstring>
+#include <string>
+#include "sema.h"
+#include "util.h"
+
+using namespace std;
+
+t_semaphore::t_semaphore(unsigned int value) {
+	int ret;
+
+	ret = sem_init(&sem, 0, value);
+	if (ret != 0) {
+		string err = get_error_str(errno);
+		string exception =
+			"t_semaphore::t_semaphore failed to create a semaphore.\n";
+		exception += err;
+		throw exception;
+	}
+}
+
+t_semaphore::~t_semaphore() {
+	sem_destroy(&sem);
+}
+
+void t_semaphore::up(void) {
+	int ret;
+
+	ret = sem_post(&sem);
+	if (ret != 0) {
+		string err = get_error_str(errno);
+		string exception = "t_semaphore::up failed.\n";
+		exception += err;
+		throw exception;
+	}
+}
+
+void t_semaphore::down(void) {
+	while (true) {
+		int ret = sem_wait(&sem);
+
+		if (ret != 0 && errno == EINTR) {
+			// In NPTL threading sem_wait can be interrupted.
+			// In LinuxThreads threading sem_wait is non-interruptable.
+			// Continue with sem_wait if an interrupt is caught.
+			continue;
+		}
+
+		break;
+	}
+}
+
+bool t_semaphore::try_down(void) {
+	int ret;
+
+	ret = sem_trywait(&sem);
+	return (ret == 0);
+}