Simplify the raw_svector_ostream tweak from r212816

[oota-llvm.git] / lib / Support / Unix / RWMutex.inc

diff --git a/lib/Support/Unix/RWMutex.inc b/lib/Support/Unix/RWMutex.inc
index ee9853e5af7b6e9aa593792f1990f5d6d490840c..edcbd52f5f377b516f633df28b3ad9a61afad72a 100644 (file)
--- a/lib/Support/Unix/RWMutex.inc
+++ b/lib/Support/Unix/RWMutex.inc
@@ -1,4 +1,4 @@
-//= llvm/System/Unix/RWMutex.inc - Unix Reader/Writer Mutual Exclusion Lock  =//
+//= llvm/Support/Unix/RWMutex.inc - Unix Reader/Writer Mutual Exclusion Lock  =//
 //
 //                     The LLVM Compiler Infrastructure
 //
@@ -16,28 +16,36 @@
 //===          is guaranteed to work on *all* UNIX variants.
 //===----------------------------------------------------------------------===//
 
+#include "llvm/Support/Mutex.h"
+
 namespace llvm {
 
 using namespace sys;
 
-RWMutexImpl::RWMutexImpl() { }
+// This naive implementation treats readers the same as writers.  This
+// will therefore deadlock if a thread tries to acquire a read lock
+// multiple times.
+
+RWMutexImpl::RWMutexImpl() : data_(new Mutex(false)) { }
 
-RWMutexImpl::~RWMutexImpl() { }
+RWMutexImpl::~RWMutexImpl() {
+  delete static_cast<Mutex *>(data_);
+}
 
 bool RWMutexImpl::reader_acquire() {
-  return true;
+  return static_cast<Mutex *>(data_)->acquire();
 }
 
 bool RWMutexImpl::reader_release() {
-  return true;
+  return static_cast<Mutex *>(data_)->release();
 }
 
 bool RWMutexImpl::writer_acquire() {
-  return true;
+  return static_cast<Mutex *>(data_)->acquire();
 }
 
 bool RWMutexImpl::writer_release() {
-  return true;
+  return static_cast<Mutex *>(data_)->release();
 }
 
 }