blob: f60ce8b1c5f208bcac71280203d44e03dd48ebff [file] [log] [blame]
// Copyright (c) 2006-2008 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.
// The memory_watcher.dll is hooked by simply linking it. When we get the
// windows notification that this DLL is loaded, we do a few things:
// 1) Register a Hot Key.
// Only one process can hook the Hot Key, so one will get it, and the
// others will silently fail.
// 2) Create a thread to wait on an event.
// Since only one process will get the HotKey, it will be responsible for
// notifying all process when it's time to do something. Each process
// will have a thread waiting for communication from the master to dump
// the callstacks.
#include <windows.h>
#include "tools/memory_watcher/memory_watcher.h"
#include "tools/memory_watcher/hotkey.h"
static wchar_t* kDumpEvent = L"MemWatcher.DumpEvent";
static MemoryWatcher* g_memory_watcher = NULL;
static HANDLE g_dump_event = INVALID_HANDLE_VALUE;
static HANDLE g_quit_event = INVALID_HANDLE_VALUE;
static HANDLE g_watcher_thread = INVALID_HANDLE_VALUE;
// A HotKey to dump the memory statistics.
class MemoryWatcherDumpKey : public HotKeyHandler {
public:
MemoryWatcherDumpKey(UINT modifiers, UINT vkey)
: HotKeyHandler(modifiers, vkey) {}
virtual LRESULT OnHotKey(UINT, WPARAM, LPARAM, BOOL& bHandled) {
SetEvent(g_dump_event);
return 1;
}
};
// Register ALT-CONTROL-D to Dump Memory stats.
MemoryWatcherDumpKey hHotKeyHandler(MOD_ALT|MOD_CONTROL, 0x44);
// Creates the global memory watcher.
void CreateMemoryWatcher() {
g_memory_watcher = new MemoryWatcher();
}
// Deletes the global memory watcher.
void DeleteMemoryWatcher() {
if (g_memory_watcher)
delete g_memory_watcher;
g_memory_watcher = NULL;
}
// Thread for watching for key events.
DWORD WINAPI ThreadMain(LPVOID) {
bool stopping = false;
HANDLE events[2] = { g_dump_event, g_quit_event };
while (!stopping) {
DWORD rv = WaitForMultipleObjects(2, events, FALSE, INFINITE);
switch (rv) {
case WAIT_OBJECT_0:
if (g_memory_watcher) {
g_memory_watcher->DumpLeaks();
}
stopping = true;
break;
case WAIT_OBJECT_0 + 1:
stopping = true;
break;
default:
NOTREACHED();
break;
}
}
return 0;
}
// Creates the background thread
void CreateBackgroundThread() {
// Create a named event which can be used to notify
// all watched processes.
g_dump_event = CreateEvent(0, TRUE, FALSE, kDumpEvent);
DCHECK(g_dump_event != NULL);
// Create a local event which can be used to kill our
// background thread.
g_quit_event = CreateEvent(0, TRUE, FALSE, NULL);
DCHECK(g_quit_event != NULL);
// Create the background thread.
g_watcher_thread = CreateThread(0,
0,
ThreadMain,
0,
0,
0);
DCHECK(g_watcher_thread != NULL);
}
// Tell the background thread to stop.
void StopBackgroundThread() {
// Send notification to our background thread.
SetEvent(g_quit_event);
// Wait for our background thread to die.
DWORD rv = WaitForSingleObject(g_watcher_thread, INFINITE);
DCHECK(rv == WAIT_OBJECT_0);
// Cleanup our global handles.
CloseHandle(g_quit_event);
CloseHandle(g_dump_event);
CloseHandle(g_watcher_thread);
}
bool IsChromeExe() {
return GetModuleHandleA("chrome.exe") != NULL;
}
extern "C" {
// DllMain is the windows entry point to this DLL.
// We use the entry point as the mechanism for starting and stopping
// the MemoryWatcher.
BOOL WINAPI DllMain(HINSTANCE dll_instance, DWORD reason,
LPVOID reserved) {
if (!IsChromeExe())
return FALSE;
switch (reason) {
case DLL_PROCESS_ATTACH:
CreateMemoryWatcher();
CreateBackgroundThread();
break;
case DLL_PROCESS_DETACH:
DeleteMemoryWatcher();
StopBackgroundThread();
break;
}
return TRUE;
}
__declspec(dllexport) void __cdecl SetLogName(char* name) {
g_memory_watcher->SetLogName(name);
}
} // extern "C"