mach_port_deallocate() the result of mach_thread_self(), which obtains a port send right.

base/threading/platform_thread_unittest.cc

 // Copyright (c) 2011 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/compiler_specific.h"
 #include "base/threading/platform_thread.h"
 
 #include "testing/gtest/include/gtest/gtest.h"
 
 namespace base {
 
 // Trivial tests that thread runs and doesn't crash on create and join ---------
 
 class TrivialThread : public PlatformThread::Delegate {
  public:
   TrivialThread() : did_run_(false) {}
 
-  virtual void ThreadMain() {
+  virtual void ThreadMain() OVERRIDE {
     did_run_ = true;
   }
 
   bool did_run() const { return did_run_; }
 
  private:
   bool did_run_;
 
   DISALLOW_COPY_AND_ASSIGN(TrivialThread);
 };
@@ skipping 21 matching lines @@
   for (size_t n = 0; n < arraysize(thread); n++)
     ASSERT_TRUE(thread[n].did_run());
 }
 
 // Tests of basic thread functions ---------------------------------------------
 
 class FunctionTestThread : public TrivialThread {
  public:
   FunctionTestThread() : thread_id_(0) {}
 
-  virtual void ThreadMain() {
+  virtual void ThreadMain() OVERRIDE {
     thread_id_ = PlatformThread::CurrentId();
     PlatformThread::YieldCurrentThread();
     PlatformThread::Sleep(TimeDelta::FromMilliseconds(50));
 
+    // Make sure that the thread ID is the same across calls.
+    EXPECT_EQ(thread_id_, PlatformThread::CurrentId());
+
     TrivialThread::ThreadMain();
   }
 
   PlatformThreadId thread_id() const { return thread_id_; }
 
  private:
   PlatformThreadId thread_id_;
 
   DISALLOW_COPY_AND_ASSIGN(FunctionTestThread);
 };
 
 TEST(PlatformThreadTest, Function) {
   PlatformThreadId main_thread_id = PlatformThread::CurrentId();
 
   FunctionTestThread thread;
   PlatformThreadHandle handle = kNullThreadHandle;
 
   ASSERT_FALSE(thread.did_run());
   ASSERT_TRUE(PlatformThread::Create(0, &thread, &handle));
   PlatformThread::Join(handle);
   ASSERT_TRUE(thread.did_run());
   EXPECT_NE(thread.thread_id(), main_thread_id);
+
+  // Make sure that the thread ID is the same across calls.
+  EXPECT_EQ(main_thread_id, PlatformThread::CurrentId());
 }
 
 TEST(PlatformThreadTest, FunctionTimesTen) {
   PlatformThreadId main_thread_id = PlatformThread::CurrentId();
 
   FunctionTestThread thread[10];
   PlatformThreadHandle handle[arraysize(thread)];
 
   for (size_t n = 0; n < arraysize(thread); n++)
     ASSERT_FALSE(thread[n].did_run());
   for (size_t n = 0; n < arraysize(thread); n++)
     ASSERT_TRUE(PlatformThread::Create(0, &thread[n], &handle[n]));
   for (size_t n = 0; n < arraysize(thread); n++)
     PlatformThread::Join(handle[n]);
   for (size_t n = 0; n < arraysize(thread); n++) {
     ASSERT_TRUE(thread[n].did_run());
     EXPECT_NE(thread[n].thread_id(), main_thread_id);
+
+    // Make sure no two threads get the same ID.
+    for (size_t i = 0; i < n; ++i) {
+      EXPECT_NE(thread[i].thread_id(), thread[n].thread_id());
+    }
   }
+
+  // Make sure that the thread ID is the same across calls.
+  EXPECT_EQ(main_thread_id, PlatformThread::CurrentId());
 }
 
 }  // namespace base