Tracking HWND creation/deletion

base/win_util.cc

Index: base/win_util.cc
===================================================================
--- base/win_util.cc	(revision 9111)
+++ base/win_util.cc	(working copy)
@@ -4,12 +4,15 @@
 
 #include "base/win_util.h"
 
+#include <map>
 #include <sddl.h>
 
 #include "base/logging.h"
 #include "base/registry.h"
 #include "base/scoped_handle.h"
+#include "base/singleton.h"
 #include "base/string_util.h"
+#include "base/tracked.h"
 
 namespace win_util {
 
@@ -361,6 +364,66 @@
   return FormatMessage(GetLastError());
 }
 
+typedef std::map<HWND, tracked_objects::Location> HWNDInfoMap;
+struct HWNDBirthMapTrait : public DefaultSingletonTraits<HWNDInfoMap> {
+};
+struct HWNDDeathMapTrait : public DefaultSingletonTraits<HWNDInfoMap> {
+};
+
+void NotifyHWNDCreation(const tracked_objects::Location& from_here, HWND hwnd) {
+  HWNDInfoMap* birth_map = Singleton<HWNDInfoMap, HWNDBirthMapTrait>::get();
+  HWNDInfoMap::iterator birth_iter = birth_map->find(hwnd);
+  if (birth_iter != birth_map->end()) {
+    birth_map->erase(birth_iter);
+
+    // We have already seen this HWND, was it destroyed?
+    HWNDInfoMap* death_map = Singleton<HWNDInfoMap, HWNDDeathMapTrait>::get();
+    HWNDInfoMap::iterator death_iter = death_map->find(hwnd);
+    if (death_iter == death_map->end()) {
+      // We did not get a destruction notification.  The code is probably not
+      // calling NotifyHWNDDestruction for that HWND.
+      NOTREACHED() << "Creation of HWND reported for already tracked HWND. The "
+                      "HWND destruction is probably not tracked properly. "
+                      "Fix it!";
+    } else {
+      death_map->erase(death_iter);
+    }
+  }
+  birth_map->insert(std::pair<HWND, tracked_objects::Location>(hwnd,
+                                                              from_here));
+}
+
+void NotifyHWNDDestruction(const tracked_objects::Location& from_here,
+                           HWND hwnd) {
+  HWNDInfoMap* death_map = Singleton<HWNDInfoMap, HWNDDeathMapTrait>::get();
+  HWNDInfoMap::iterator death_iter = death_map->find(hwnd);
+
+  HWNDInfoMap* birth_map = Singleton<HWNDInfoMap, HWNDBirthMapTrait>::get();
+  HWNDInfoMap::iterator birth_iter = birth_map->find(hwnd);
+
+  if (death_iter != death_map->end()) {
+    std::string allocation, first_delete, second_delete;
+    if (birth_iter != birth_map->end())
+      birth_iter->second.Write(true, true, &allocation);
+    death_iter->second.Write(true, true, &first_delete);
+    from_here.Write(true, true, &second_delete);
+    NOTREACHED() << "Double delete of an HWND. Please file a bug with info on "
+        "how you got that assertion and the following information:\n"
+        "Double delete of HWND 0x" << hwnd << "\n" <<
+        "Allocated at " << allocation << "\n" <<
+        "Deleted first at " << first_delete << "\n" <<
+        "Deleted again at " << second_delete;
+    death_map->erase(death_iter);
+  }
+
+  if (birth_iter == birth_map->end()) {
+    NOTREACHED() << "Destruction of HWND reported for unknown HWND. The HWND "
+                    "construction is probably not tracked properly. Fix it!";
+  }
+  death_map->insert(std::pair<HWND, tracked_objects::Location>(hwnd,
+                                                               from_here));
+}
+
 }  // namespace win_util
 
 #ifdef _MSC_VER