From bdb6a08704e4e349ccacd8a853a51c9983afe0da Mon Sep 17 00:00:00 2001
From: Ali Mashtizadeh <mashti@cs.stanford.edu>
Date: Fri, 30 Jan 2015 20:44:01 -0800
Subject: [PATCH] CoreMutex cleanup and add to build

---
 include/core/mutex.h  | 12 ++++++------
 lib/libc/SConscript   |  1 +
 lib/libc/core/mutex.c | 13 ++++++++-----
 3 files changed, 15 insertions(+), 11 deletions(-)

diff --git a/include/core/mutex.h b/include/core/mutex.h
index b507e0b..b1a1538 100644
--- a/include/core/mutex.h
+++ b/include/core/mutex.h
@@ -2,14 +2,14 @@
 #ifndef __CORE_MUTEX_H__
 #define __CORE_MUTEX_H__
 
-typedef struct Mutex {
+typedef struct CoreMutex {
     uint64_t	lock;
-} Mutex;
+} CoreMutex;
 
-int CoreMutex_Init(Mutex *mtx);
-void CoreMutex_Lock(Mutex *mtx);
-bool CoreMutex_TryLock(Mutex *mtx);
-void CoreMutex_Unlock(Mutex *mtx);
+void CoreMutex_Init(CoreMutex *mtx);
+void CoreMutex_Lock(CoreMutex *mtx);
+bool CoreMutex_TryLock(CoreMutex *mtx);
+void CoreMutex_Unlock(CoreMutex *mtx);
 
 #endif /* __CORE_MUTEX_H__ */
 
diff --git a/lib/libc/SConscript b/lib/libc/SConscript
index 768eef0..9349fac 100644
--- a/lib/libc/SConscript
+++ b/lib/libc/SConscript
@@ -9,6 +9,7 @@ src = [ ]
 src_common = [
     "abort.c",
     "assert.c",
+    "core/mutex.c",
     "dir.c",
     "exit.c",
     "file.c",
diff --git a/lib/libc/core/mutex.c b/lib/libc/core/mutex.c
index 227877f..35b423c 100644
--- a/lib/libc/core/mutex.c
+++ b/lib/libc/core/mutex.c
@@ -2,23 +2,26 @@
 #include <stdbool.h>
 #include <stdint.h>
 
+#include <syscall.h>
 #include <core/mutex.h>
 
-int
-CoreMutex_Init(Mutex *mtx)
+void
+CoreMutex_Init(CoreMutex *mtx)
 {
+    mtx->lock = 0;
 }
 
 
 void
-CoreMutex_Lock(Mutex *mtx)
+CoreMutex_Lock(CoreMutex *mtx)
 {
     while (__sync_lock_test_and_set(&mtx->lock, 1) == 1) {
+	OSThreadSleep(0);
     }
 }
 
 bool
-CoreMutex_TryLock(Mutex *mtx)
+CoreMutex_TryLock(CoreMutex *mtx)
 {
     if (__sync_lock_test_and_set(&mtx->lock, 1) == 1) {
 	return false;
@@ -28,7 +31,7 @@ CoreMutex_TryLock(Mutex *mtx)
 }
 
 void
-CoreMutex_Unlock(Mutex *mtx)
+CoreMutex_Unlock(CoreMutex *mtx)
 {
     __sync_lock_release(&mtx->lock);
 }