Add a void* parameter to the AtExitManager callbacks.

Review URL: http://codereview.chromium.org/1805

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@1835 0039d316-1c4b-4281-b951-d872f2087c98

4 files changed, 47 insertions, 30 deletions

diff --git a/base/at_exit.cc b/base/at_exit.cc
index fb4e8c9..9fdfd77 100644
--- a/base/at_exit.cc
+++ b/base/at_exit.cc
@@ -35,14 +35,16 @@ AtExitManager::~AtExitManager() {
 }
 
 // static
-void AtExitManager::RegisterCallback(AtExitCallbackType func) {
+void AtExitManager::RegisterCallback(AtExitCallbackType func, void* param) {
   if (!g_top_manager) {
     NOTREACHED() << "Tried to RegisterCallback without an AtExitManager";
     return;
   }
 
+  DCHECK(func);
+
   AutoLock lock(g_top_manager->lock_);
-  g_top_manager->stack_.push(func);
+  g_top_manager->stack_.push(CallbackAndParam(func, param));
 }
 
 // static
@@ -55,12 +57,11 @@ void AtExitManager::ProcessCallbacksNow() {
   AutoLock lock(g_top_manager->lock_);
 
   while (!g_top_manager->stack_.empty()) {
-    AtExitCallbackType func = g_top_manager->stack_.top();
+    CallbackAndParam callback_and_param = g_top_manager->stack_.top();
     g_top_manager->stack_.pop();
-    if (func)
-      func();
+
+    callback_and_param.func_(callback_and_param.param_);
   }
 }
 
 }  // namespace base
-
diff --git a/base/at_exit.h b/base/at_exit.h
index 94dff08..aecc892 100644
--- a/base/at_exit.h
+++ b/base/at_exit.h
@@ -35,7 +35,7 @@ class AtExitManager {
   AtExitManager(bool shadow);
 
  public:
-  typedef void (*AtExitCallbackType)();
+  typedef void (*AtExitCallbackType)(void*);
 
   AtExitManager();
 
@@ -45,15 +45,22 @@ class AtExitManager {
 
   // Registers the specified function to be called at exit. The prototype of
   // the callback function is void func().
-  static void RegisterCallback(AtExitCallbackType func);
+  static void RegisterCallback(AtExitCallbackType func, void* param);
 
   // Calls the functions registered with RegisterCallback in LIFO order. It
   // is possible to register new callbacks after calling this function.
   static void ProcessCallbacksNow();
 
  private:
+  struct CallbackAndParam {
+    CallbackAndParam(AtExitCallbackType func, void* param)
+        : func_(func), param_(param) { }
+    AtExitCallbackType func_;
+    void* param_;
+  };
+
   Lock lock_;
-  std::stack<AtExitCallbackType> stack_;
+  std::stack<CallbackAndParam> stack_;
   AtExitManager* next_manager_;  // Stack of managers to allow shadowing.
 
   DISALLOW_COPY_AND_ASSIGN(AtExitManager);
@@ -62,4 +69,3 @@ class AtExitManager {
 }  // namespace base
 
 #endif  // BASE_AT_EXIT_H_
-
diff --git a/base/at_exit_unittest.cc b/base/at_exit_unittest.cc
index 46815d0..d80d68c 100644
--- a/base/at_exit_unittest.cc
+++ b/base/at_exit_unittest.cc
@@ -18,11 +18,11 @@ class ShadowingAtExitManager : public base::AtExitManager {
 int g_test_counter_1 = 0;
 int g_test_counter_2 = 0;
 
-void IncrementTestCounter1() {
+void IncrementTestCounter1(void* unused) {
   ++g_test_counter_1;
 }
 
-void IncrementTestCounter2() {
+void IncrementTestCounter2(void* unused) {
   ++g_test_counter_2;
 }
 
@@ -31,19 +31,27 @@ void ZeroTestCounters() {
   g_test_counter_2 = 0;
 }
 
-void ExpectCounter1IsZero() {
+void ExpectCounter1IsZero(void* unused) {
   EXPECT_EQ(0, g_test_counter_1);
 }
 
+void ExpectParamIsNull(void* param) {
+  EXPECT_EQ(static_cast<void*>(NULL), param);
+}
+
+void ExpectParamIsCounter(void* param) {
+  EXPECT_EQ(&g_test_counter_1, param);
+}
+
 }  // namespace
 
 TEST(AtExitTest, Basic) {
   ShadowingAtExitManager shadowing_at_exit_manager;
 
   ZeroTestCounters();
-  base::AtExitManager::RegisterCallback(&IncrementTestCounter1);
-  base::AtExitManager::RegisterCallback(&IncrementTestCounter2);
-  base::AtExitManager::RegisterCallback(&IncrementTestCounter1);
+  base::AtExitManager::RegisterCallback(&IncrementTestCounter1, NULL);
+  base::AtExitManager::RegisterCallback(&IncrementTestCounter2, NULL);
+  base::AtExitManager::RegisterCallback(&IncrementTestCounter1, NULL);
   
   EXPECT_EQ(0, g_test_counter_1);
   EXPECT_EQ(0, g_test_counter_2);
@@ -56,9 +64,9 @@ TEST(AtExitTest, LIFOOrder) {
   ShadowingAtExitManager shadowing_at_exit_manager;
 
   ZeroTestCounters();
-  base::AtExitManager::RegisterCallback(&IncrementTestCounter1);
-  base::AtExitManager::RegisterCallback(&ExpectCounter1IsZero);
-  base::AtExitManager::RegisterCallback(&IncrementTestCounter2);
+  base::AtExitManager::RegisterCallback(&IncrementTestCounter1, NULL);
+  base::AtExitManager::RegisterCallback(&ExpectCounter1IsZero, NULL);
+  base::AtExitManager::RegisterCallback(&IncrementTestCounter2, NULL);
   
   EXPECT_EQ(0, g_test_counter_1);
   EXPECT_EQ(0, g_test_counter_2);
@@ -67,3 +75,11 @@ TEST(AtExitTest, LIFOOrder) {
   EXPECT_EQ(1, g_test_counter_2);
 }
 
+TEST(AtExitTest, Param) {
+  ShadowingAtExitManager shadowing_at_exit_manager;
+
+  base::AtExitManager::RegisterCallback(&ExpectParamIsNull, NULL);
+  base::AtExitManager::RegisterCallback(&ExpectParamIsCounter,
+                                        &g_test_counter_1);
+  base::AtExitManager::ProcessCallbacksNow();
+}
diff --git a/base/singleton.h b/base/singleton.h
index 9c21d53..c6a1685 100644
--- a/base/singleton.h
+++ b/base/singleton.h
@@ -2,12 +2,8 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
-#ifndef BASE_SINGLETON_H__
-#define BASE_SINGLETON_H__
-
-#include <stdlib.h>
-
-#include <utility>
+#ifndef BASE_SINGLETON_H_
+#define BASE_SINGLETON_H_
 
 #include "base/at_exit.h"
 #include "base/atomicops.h"
@@ -125,7 +121,7 @@ class Singleton {
           &instance_, reinterpret_cast<base::subtle::AtomicWord>(newval));
 
       if (Traits::kRegisterAtExit)
-        base::AtExitManager::RegisterCallback(OnExit);
+        base::AtExitManager::RegisterCallback(OnExit, NULL);
 
       return newval;
     }
@@ -159,7 +155,7 @@ class Singleton {
  private:
   // Adapter function for use with AtExit().  This should be called single
   // threaded, but we might as well take the precautions anyway.
-  static void OnExit() {
+  static void OnExit(void* unused) {
     // AtExit should only ever be register after the singleton instance was
     // created.  We should only ever get here with a valid instance_ pointer.
     Traits::Delete(reinterpret_cast<Type*>(
@@ -172,6 +168,4 @@ template <typename Type, typename Traits, typename DifferentiatingType>
 base::subtle::AtomicWord Singleton<Type, Traits, DifferentiatingType>::
     instance_ = 0;
 
-
-#endif  // BASE_SINGLETON_H__
-
+#endif  // BASE_SINGLETON_H_