blob: d26676fe0f7fb1d552040185afd4098a3fb01221 [file] [log] [blame]
// 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 <windows.h>
#include <malloc.h>
#include <shellscalingapi.h>
#include <tchar.h>
#include <string>
#include "base/at_exit.h"
#include "base/command_line.h"
#include "base/files/file_path.h"
#include "base/logging.h"
#include "base/time/time.h"
#include "base/win/windows_version.h"
#include "chrome/app/main_dll_loader_win.h"
#include "chrome/browser/chrome_process_finder_win.h"
#include "chrome/browser/policy/policy_path_parser.h"
#include "chrome/common/chrome_paths_internal.h"
#include "chrome/common/chrome_switches.h"
#include "chrome_elf/chrome_elf_main.h"
#include "components/startup_metric_utils/startup_metric_utils.h"
#include "content/public/common/result_codes.h"
#include "ui/gfx/win/dpi.h"
namespace {
// List of switches that it's safe to rendezvous early with. Fast start should
// not be done if a command line contains a switch not in this set.
// Note this is currently stored as a list of two because it's probably faster
// to iterate over this small array than building a map for constant time
// lookups.
const char* const kFastStartSwitches[] = {
bool IsFastStartSwitch(const std::string& command_line_switch) {
for (size_t i = 0; i < arraysize(kFastStartSwitches); ++i) {
if (command_line_switch == kFastStartSwitches[i])
return true;
return false;
bool ContainsNonFastStartFlag(const base::CommandLine& command_line) {
const base::CommandLine::SwitchMap& switches = command_line.GetSwitches();
if (switches.size() > arraysize(kFastStartSwitches))
return true;
for (base::CommandLine::SwitchMap::const_iterator it = switches.begin();
it != switches.end(); ++it) {
if (!IsFastStartSwitch(it->first))
return true;
return false;
bool AttemptFastNotify(const base::CommandLine& command_line) {
if (ContainsNonFastStartFlag(command_line))
return false;
base::FilePath user_data_dir;
if (!chrome::GetDefaultUserDataDirectory(&user_data_dir))
return false;
HWND chrome = chrome::FindRunningChromeWindow(user_data_dir);
if (!chrome)
return false;
return chrome::AttemptToNotifyRunningChrome(chrome, true) ==
// Win8.1 supports monitor-specific DPI scaling.
bool SetProcessDpiAwarenessWrapper(PROCESS_DPI_AWARENESS value) {
typedef HRESULT(WINAPI *SetProcessDpiAwarenessPtr)(PROCESS_DPI_AWARENESS);
SetProcessDpiAwarenessPtr set_process_dpi_awareness_func =
if (set_process_dpi_awareness_func) {
HRESULT hr = set_process_dpi_awareness_func(value);
if (SUCCEEDED(hr)) {
VLOG(1) << "SetProcessDpiAwareness succeeded.";
return true;
} else if (hr == E_ACCESSDENIED) {
LOG(ERROR) << "Access denied error from SetProcessDpiAwareness. "
"Function called twice, or manifest was used.";
return false;
// This function works for Windows Vista through Win8. Win8.1 must use
// SetProcessDpiAwareness[Wrapper].
BOOL SetProcessDPIAwareWrapper() {
typedef BOOL(WINAPI *SetProcessDPIAwarePtr)(VOID);
SetProcessDPIAwarePtr set_process_dpi_aware_func =
return set_process_dpi_aware_func &&
void EnableHighDPISupport() {
if (!SetProcessDpiAwarenessWrapper(PROCESS_SYSTEM_DPI_AWARE)) {
void SwitchToLFHeap() {
// Only needed on XP but harmless on other Windows flavors.
auto crt_heap = _get_heap_handle();
ULONG enable_LFH = 2;
if (HeapSetInformation(reinterpret_cast<HANDLE>(crt_heap),
&enable_LFH, sizeof(enable_LFH))) {
VLOG(1) << "Low fragmentation heap enabled.";
} // namespace
int APIENTRY wWinMain(HINSTANCE instance, HINSTANCE prev, wchar_t*, int) {
// The AddressSanitizer build should be a console program as it prints out stuff
// on stderr.
int main() {
HINSTANCE instance = GetModuleHandle(NULL);
// Signal Chrome Elf that Chrome has begun to start.
// Initialize the commandline singleton from the environment.
base::CommandLine::Init(0, NULL);
// The exit manager is in charge of calling the dtors of singletons.
base::AtExitManager exit_manager;
// We don't want to set DPI awareness on pre-Win7 because we don't support
// DirectWrite there. GDI fonts are kerned very badly, so better to leave
// DPI-unaware and at effective 1.0. See also ShouldUseDirectWrite().
if (base::win::GetVersion() >= base::win::VERSION_WIN7)
if (AttemptFastNotify(*base::CommandLine::ForCurrentProcess()))
return 0;
// Load and launch the chrome dll. *Everything* happens inside.
VLOG(1) << "About to load main DLL.";
MainDllLoader* loader = MakeMainDllLoader();
int rc = loader->Launch(instance);
delete loader;
return rc;