1 files changed, 41 insertions, 0 deletions
diff --git a/src/ao_mutex.c b/src/ao_mutex.c
new file mode 100644
index 00000000..c82a7d57
--- /dev/null
+++ b/src/ao_mutex.c
@@ -0,0 +1,41 @@
+/*
+ * Copyright © 2009 Keith Packard <keithp@keithp.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; version 2 of the License.
+ *
+ * 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 "ao.h"
+
+void
+ao_mutex_get(__xdata uint8_t *mutex) __reentrant
+{
+	if (*mutex == ao_cur_task->task_id)
+		ao_panic(AO_PANIC_MUTEX);
+	__critical {
+		while (*mutex)
+			ao_sleep(mutex);
+		*mutex = ao_cur_task->task_id;
+	}
+}
+
+void
+ao_mutex_put(__xdata uint8_t *mutex) __reentrant
+{
+	if (*mutex != ao_cur_task->task_id)
+		ao_panic(AO_PANIC_MUTEX);
+	__critical {
+		*mutex = 0;
+		ao_wakeup(mutex);
+	}
+}