Add multi_process_lock to chrome/common

chrome/common/multi_process_lock_unittest.cc

Index: chrome/common/multi_process_lock_unittest.cc
diff --git a/chrome/common/multi_process_lock_unittest.cc b/chrome/common/multi_process_lock_unittest.cc
new file mode 100644
index 0000000000000000000000000000000000000000..0743236691cca52028a52cceab1402c61a1de1b2
--- /dev/null
+++ b/chrome/common/multi_process_lock_unittest.cc
@@ -0,0 +1,48 @@
+// Copyright (c) 2010 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#include "base/basictypes.h"
+#include "base/scoped_ptr.h"
+#include "base/test/multiprocess_test.h"
+#include "chrome/common/multi_process_lock.h"
+#include "testing/multiprocess_func_list.h"
+
+static const char kMutexName[] = "shared_mutex_unittest";
+
+class MultiProcessLockTest : public base::MultiProcessTest {
+};
+
+TEST_F(MultiProcessLockTest, BasicCreationTest) {
+  // Test basic creation/destruction with no lock taken
+  scoped_ptr<MultiProcessLock> scoped(MultiProcessLock::Create(kMutexName));
+  scoped.reset(NULL);
+}
+
+TEST_F(MultiProcessLockTest, SimpleLock) {
+  scoped_ptr<MultiProcessLock> test_lock(MultiProcessLock::Create(kMutexName));
+  EXPECT_TRUE(test_lock->TryLock());
+  base::ProcessHandle handle = SpawnChild("MultiProcessLockTryFailMain", false);
+  ASSERT_TRUE(handle);
+  int exit_code = 0;
+  EXPECT_TRUE(base::WaitForExitCode(handle, &exit_code));
+  EXPECT_EQ(exit_code, 0);
+  test_lock->Unlock();
+  handle = SpawnChild("MultiProcessLockTrySucceedMain", false);
+  ASSERT_TRUE(handle);
+  EXPECT_TRUE(base::WaitForExitCode(handle, &exit_code));
+  EXPECT_EQ(exit_code, 0);
+}
+
+MULTIPROCESS_TEST_MAIN(MultiProcessLockTryFailMain) {
+  scoped_ptr<MultiProcessLock> test_lock(MultiProcessLock::Create(kMutexName));
+  EXPECT_FALSE(test_lock->TryLock());
+  return 0;
+}
+
+
+MULTIPROCESS_TEST_MAIN(MultiProcessLockTrySucceedMain) {
+  scoped_ptr<MultiProcessLock> test_lock(MultiProcessLock::Create(kMutexName));
+  EXPECT_TRUE(test_lock->TryLock());
+  return 0;
+}