--- /dev/null
+/*
+ * Synchronization primitives
+ * Copyright (c) 2001, David H. Hovemeyer <daveho@cs.umd.edu>
+ * $Revision: 1.1 $
+ *
+ * This is free software. You are permitted to use,
+ * redistribute, and modify it as specified in the file "COPYING".
+ */
+
+#ifndef GEEKOS_SYNCH_H
+#define GEEKOS_SYNCH_H
+
+#include <geekos/kthread.h>
+
+/*
+ * mutex states
+ */
+enum { MUTEX_UNLOCKED, MUTEX_LOCKED };
+
+struct Mutex {
+ int state;
+ struct Kernel_Thread* owner;
+ struct Thread_Queue waitQueue;
+};
+
+#define MUTEX_INITIALIZER { MUTEX_UNLOCKED, 0, THREAD_QUEUE_INITIALIZER }
+
+struct Condition {
+ struct Thread_Queue waitQueue;
+};
+
+void Mutex_Init(struct Mutex* mutex);
+void Mutex_Lock(struct Mutex* mutex);
+void Mutex_Unlock(struct Mutex* mutex);
+void Mutex_Destroy(struct Mutex *mutex);
+
+void Cond_Init(struct Condition* cond);
+void Cond_Wait(struct Condition* cond, struct Mutex* mutex);
+int Cond_Wait_Timeout(struct Condition * cond, struct Mutex * mutex, uint_t ms);
+void Cond_Signal(struct Condition* cond);
+void Cond_Broadcast(struct Condition* cond);
+void Cond_Destroy(struct Condition *cond);
+
+#define IS_HELD(mutex) \
+ ((mutex)->state == MUTEX_LOCKED && (mutex)->owner == g_currentThread)
+
+#endif /* GEEKOS_SYNCH_H */
