Add unit tests for base/platform_thread.* and base/lock.*.

BUG=none
TEST=base_unittests

Review URL: http://codereview.chromium.org/3030025

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@54283 0039d316-1c4b-4281-b951-d872f2087c98

1 files changed, 213 insertions, 0 deletions

diff --git a/base/lock_unittest.cc b/base/lock_unittest.cc
new file mode 100644
index 0000000..cf99df9
--- /dev/null
+++ b/base/lock_unittest.cc
@@ -0,0 +1,213 @@
+// 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/lock.h"
+
+#include <stdlib.h>
+
+#include "base/platform_thread.h"
+#include "testing/gtest/include/gtest/gtest.h"
+
+typedef testing::Test LockTest;
+
+// Basic test to make sure that Acquire()/Release()/Try() don't crash ----------
+
+class BasicLockTestThread : public PlatformThread::Delegate {
+ public:
+  BasicLockTestThread(Lock* lock) : lock_(lock), acquired_(0) {}
+
+  virtual void ThreadMain() {
+    for (int i = 0; i < 10; i++) {
+      lock_->Acquire();
+      acquired_++;
+      lock_->Release();
+    }
+    for (int i = 0; i < 10; i++) {
+      lock_->Acquire();
+      acquired_++;
+      PlatformThread::Sleep(rand() % 20);
+      lock_->Release();
+    }
+    for (int i = 0; i < 10; i++) {
+      if (lock_->Try()) {
+        acquired_++;
+        PlatformThread::Sleep(rand() % 20);
+        lock_->Release();
+      }
+    }
+  }
+
+  int acquired() const { return acquired_; }
+
+ private:
+  Lock* lock_;
+  int acquired_;
+
+  DISALLOW_COPY_AND_ASSIGN(BasicLockTestThread);
+};
+
+TEST_F(LockTest, Basic) {
+  Lock lock;
+  BasicLockTestThread thread(&lock);
+  PlatformThreadHandle handle = kNullThreadHandle;
+
+  ASSERT_TRUE(PlatformThread::Create(0, &thread, &handle));
+
+  int acquired = 0;
+  for (int i = 0; i < 5; i++) {
+    lock.Acquire();
+    acquired++;
+    lock.Release();
+  }
+  for (int i = 0; i < 10; i++) {
+    lock.Acquire();
+    acquired++;
+    PlatformThread::Sleep(rand() % 20);
+    lock.Release();
+  }
+  for (int i = 0; i < 10; i++) {
+    if (lock.Try()) {
+      acquired++;
+      PlatformThread::Sleep(rand() % 20);
+      lock.Release();
+    }
+  }
+  for (int i = 0; i < 5; i++) {
+    lock.Acquire();
+    acquired++;
+    PlatformThread::Sleep(rand() % 20);
+    lock.Release();
+  }
+
+  PlatformThread::Join(handle);
+
+  EXPECT_GE(acquired, 20);
+  EXPECT_GE(thread.acquired(), 20);
+}
+
+// Test that Try() works as expected -------------------------------------------
+
+class TryLockTestThread : public PlatformThread::Delegate {
+ public:
+  TryLockTestThread(Lock* lock) : lock_(lock), got_lock_(false) {}
+
+  virtual void ThreadMain() {
+    got_lock_ = lock_->Try();
+    if (got_lock_)
+      lock_->Release();
+  }
+
+  bool got_lock() const { return got_lock_; }
+
+ private:
+  Lock* lock_;
+  bool got_lock_;
+
+  DISALLOW_COPY_AND_ASSIGN(TryLockTestThread);
+};
+
+TEST_F(LockTest, TryLock) {
+  Lock lock;
+
+  ASSERT_TRUE(lock.Try());
+  // We now have the lock....
+
+  // This thread will not be able to get the lock.
+  {
+    TryLockTestThread thread(&lock);
+    PlatformThreadHandle handle = kNullThreadHandle;
+
+    ASSERT_TRUE(PlatformThread::Create(0, &thread, &handle));
+
+    PlatformThread::Join(handle);
+
+    ASSERT_FALSE(thread.got_lock());
+  }
+
+  lock.Release();
+
+  // This thread will....
+  {
+    TryLockTestThread thread(&lock);
+    PlatformThreadHandle handle = kNullThreadHandle;
+
+    ASSERT_TRUE(PlatformThread::Create(0, &thread, &handle));
+
+    PlatformThread::Join(handle);
+
+    ASSERT_TRUE(thread.got_lock());
+    // But it released it....
+    ASSERT_TRUE(lock.Try());
+  }
+
+  lock.Release();
+}
+
+// Tests that locks actually exclude -------------------------------------------
+
+class MutexLockTestThread : public PlatformThread::Delegate {
+ public:
+  MutexLockTestThread(Lock* lock, int* value) : lock_(lock), value_(value) {}
+
+  // Static helper which can also be called from the main thread.
+  static void DoStuff(Lock* lock, int* value) {
+    for (int i = 0; i < 40; i++) {
+      lock->Acquire();
+      int v = *value;
+      PlatformThread::Sleep(rand() % 10);
+      *value = v + 1;
+      lock->Release();
+    }
+  }
+
+  virtual void ThreadMain() {
+    DoStuff(lock_, value_);
+  }
+
+ private:
+  Lock* lock_;
+  int* value_;
+
+  DISALLOW_COPY_AND_ASSIGN(MutexLockTestThread);
+};
+
+TEST_F(LockTest, MutexTwoThreads) {
+  Lock lock;
+  int value = 0;
+
+  MutexLockTestThread thread(&lock, &value);
+  PlatformThreadHandle handle = kNullThreadHandle;
+
+  ASSERT_TRUE(PlatformThread::Create(0, &thread, &handle));
+
+  MutexLockTestThread::DoStuff(&lock, &value);
+
+  PlatformThread::Join(handle);
+
+  EXPECT_EQ(2 * 40, value);
+}
+
+TEST_F(LockTest, MutexFourThreads) {
+  Lock lock;
+  int value = 0;
+
+  MutexLockTestThread thread1(&lock, &value);
+  MutexLockTestThread thread2(&lock, &value);
+  MutexLockTestThread thread3(&lock, &value);
+  PlatformThreadHandle handle1 = kNullThreadHandle;
+  PlatformThreadHandle handle2 = kNullThreadHandle;
+  PlatformThreadHandle handle3 = kNullThreadHandle;
+
+  ASSERT_TRUE(PlatformThread::Create(0, &thread1, &handle1));
+  ASSERT_TRUE(PlatformThread::Create(0, &thread2, &handle2));
+  ASSERT_TRUE(PlatformThread::Create(0, &thread3, &handle3));
+
+  MutexLockTestThread::DoStuff(&lock, &value);
+
+  PlatformThread::Join(handle1);
+  PlatformThread::Join(handle2);
+  PlatformThread::Join(handle3);
+
+  EXPECT_EQ(4 * 40, value);
+}