// 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.

// TODO(port): the ifdefs in here are a first step towards trying to determine
// the correct abstraction for all the OS functionality required at this
// stage of process initialization. It should not be taken as a final
// abstraction.

#include "build/build_config.h"

#if defined(OS_WIN)
#include <algorithm>
#include <atlbase.h>
#include <atlapp.h>
#include <malloc.h>
#include <new.h>
#elif defined(OS_POSIX)
#include <signal.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <unistd.h>
#endif

#if defined(OS_LINUX)
#include <gdk/gdk.h>
#include <glib.h>
#include <gtk/gtk.h>
#include <string.h>
#endif

#include "app/app_paths.h"
#include "app/resource_bundle.h"
#include "base/at_exit.h"
#include "base/command_line.h"
#include "base/debug_util.h"
#if defined(OS_POSIX)
#include "base/global_descriptors_posix.h"
#endif
#include "base/icu_util.h"
#include "base/message_loop.h"
#include "base/path_service.h"
#include "base/process_util.h"
#include "base/scoped_nsautorelease_pool.h"
#include "base/stats_counters.h"
#include "base/stats_table.h"
#include "base/string_util.h"
#if defined(OS_WIN)
#include "base/win_util.h"
#endif
#if defined(OS_MACOSX)
#include "chrome/app/breakpad_mac.h"
#elif defined(OS_LINUX)
#include "chrome/app/breakpad_linux.h"
#endif
#include "chrome/app/scoped_ole_initializer.h"
#include "chrome/browser/renderer_host/render_process_host.h"
#include "chrome/common/chrome_constants.h"
#include "chrome/common/chrome_counters.h"
#include "chrome/common/chrome_descriptors.h"
#include "chrome/common/chrome_paths.h"
#include "chrome/common/chrome_switches.h"
#include "chrome/common/logging_chrome.h"
#include "chrome/common/main_function_params.h"
#include "chrome/common/sandbox_init_wrapper.h"
#if defined(OS_WIN)
#include "sandbox/src/sandbox.h"
#include "tools/memory_watcher/memory_watcher.h"
#endif
#if defined(OS_MACOSX)
#include "third_party/WebKit/WebKit/mac/WebCoreSupport/WebSystemInterface.h"
#endif

extern int BrowserMain(const MainFunctionParams&);
extern int RendererMain(const MainFunctionParams&);
extern int PluginMain(const MainFunctionParams&);
extern int WorkerMain(const MainFunctionParams&);
extern int UtilityMain(const MainFunctionParams&);
extern int ZygoteMain(const MainFunctionParams&);

#if defined(OS_WIN)
// TODO(erikkay): isn't this already defined somewhere?
#define DLLEXPORT __declspec(dllexport)

// We use extern C for the prototype DLLEXPORT to avoid C++ name mangling.
extern "C" {
DLLEXPORT int __cdecl ChromeMain(HINSTANCE instance,
                                 sandbox::SandboxInterfaceInfo* sandbox_info,
                                 TCHAR* command_line);
}
#elif defined(OS_POSIX)
extern "C" {
int ChromeMain(int argc, const char** argv);
}
#endif

namespace {

#if defined(OS_WIN)
const wchar_t kProfilingDll[] = L"memory_watcher.dll";

// Load the memory profiling DLL.  All it needs to be activated
// is to be loaded.  Return true on success, false otherwise.
bool LoadMemoryProfiler() {
  HMODULE prof_module = LoadLibrary(kProfilingDll);
  return prof_module != NULL;
}

CAppModule _Module;

#pragma optimize("", off)
// Handlers for invalid parameter and pure call. They generate a breakpoint to
// tell breakpad that it needs to dump the process.
void InvalidParameter(const wchar_t* expression, const wchar_t* function,
                      const wchar_t* file, unsigned int line,
                      uintptr_t reserved) {
  __debugbreak();
}

void PureCall() {
  __debugbreak();
}

void OnNoMemory() {
  // Kill the process. This is important for security, since WebKit doesn't
  // NULL-check many memory allocations. If a malloc fails, returns NULL, and
  // the buffer is then used, it provides a handy mapping of memory starting at
  // address 0 for an attacker to utilize.
  __debugbreak();
}

// Handlers to silently dump the current process when there is an assert in
// chrome.
void ChromeAssert(const std::string& str) {
  // Get the breakpad pointer from chrome.exe
  typedef void (__cdecl *DumpProcessFunction)();
  DumpProcessFunction DumpProcess = reinterpret_cast<DumpProcessFunction>(
      ::GetProcAddress(::GetModuleHandle(chrome::kBrowserProcessExecutableName),
                       "DumpProcess"));
  if (DumpProcess)
    DumpProcess();
}

#pragma optimize("", on)

// Early versions of Chrome incorrectly registered a chromehtml: URL handler,
// which gives us nothing but trouble. Avoid launching chrome this way since
// some apps fail to properly escape arguments.
bool HasDeprecatedArguments(const std::wstring& command_line) {
  const wchar_t kChromeHtml[] = L"chromehtml:";
  std::wstring command_line_lower = command_line;
  // We are only searching for ASCII characters so this is OK.
  StringToLowerASCII(&command_line_lower);
  std::wstring::size_type pos = command_line_lower.find(kChromeHtml);
  return (pos != std::wstring::npos);
}

#endif  // OS_WIN

#if defined(OS_LINUX)
static void GLibLogHandler(const gchar* log_domain,
                           GLogLevelFlags log_level,
                           const gchar* message,
                           gpointer userdata) {
  if (!log_domain)
    log_domain = "<unknown>";
  if (!message)
    message = "<no message>";

  if (strstr(message, "Loading IM context type") ||
      strstr(message, "wrong ELF class: ELFCLASS64")) {
    // http://crbug.com/9643
    // Until we have a real 64-bit build or all of these 32-bit package issues
    // are sorted out, don't fatal on ELF 32/64-bit mismatch warnings.
    LOG(ERROR) << "Bug 9643: " << log_domain << ": " << message;
  } else if (strstr(message, "gtk_widget_size_allocate(): attempt to "
                             "allocate widget with width") &&
             !GTK_CHECK_VERSION(2, 16, 1)) {
    // http://crbug.com/11133
    LOG(ERROR) << "Bug 11133";
  } else {
#ifdef NDEBUG
    LOG(ERROR) << log_domain << ": " << message;
#else
    LOG(FATAL) << log_domain << ": " << message;
#endif
  }
}

static void SetUpGLibLogHandler() {
  // Register GLib-handled assertions to go through our logging system.
  const char* kLogDomains[] = { NULL, "Gtk", "Gdk", "GLib", "GLib-GObject" };
  for (size_t i = 0; i < arraysize(kLogDomains); i++) {
    g_log_set_handler(kLogDomains[i],
                      static_cast<GLogLevelFlags>(G_LOG_FLAG_RECURSION |
                                                  G_LOG_FLAG_FATAL |
                                                  G_LOG_LEVEL_ERROR |
                                                  G_LOG_LEVEL_CRITICAL |
                                                  G_LOG_LEVEL_WARNING),
                      GLibLogHandler,
                      NULL);
  }
}
#endif  // defined(OS_LINUX)

#if defined(OS_WIN)
extern "C" int _set_new_mode(int);
#endif

// Register the invalid param handler and pure call handler to be able to
// notify breakpad when it happens.
void RegisterInvalidParamHandler() {
#if defined(OS_WIN)
  _set_invalid_parameter_handler(InvalidParameter);
  _set_purecall_handler(PureCall);
  // Gather allocation failure.
  std::set_new_handler(&OnNoMemory);
  // Also enable the new handler for malloc() based failures.
  _set_new_mode(1);
#endif
}

void SetupCRT(const CommandLine& parsed_command_line) {
#if defined(OS_WIN)
#ifdef _CRTDBG_MAP_ALLOC
  _CrtSetReportFile(_CRT_WARN, _CRTDBG_FILE_STDERR);
  _CrtSetReportMode(_CRT_WARN, _CRTDBG_MODE_FILE);
#else
  if (!parsed_command_line.HasSwitch(switches::kDisableBreakpad)) {
    _CrtSetReportMode(_CRT_ASSERT, 0);
  }
#endif

  // Enable the low fragmentation heap for the CRT heap. The heap is not changed
  // if the process is run under the debugger is enabled or if certain gflags
  // are set.
  bool use_lfh = false;
  if (parsed_command_line.HasSwitch(switches::kUseLowFragHeapCrt))
    use_lfh = parsed_command_line.GetSwitchValue(switches::kUseLowFragHeapCrt)
        != L"false";
  if (use_lfh) {
    void* crt_heap = reinterpret_cast<void*>(_get_heap_handle());
    ULONG enable_lfh = 2;
    HeapSetInformation(crt_heap, HeapCompatibilityInformation,
                       &enable_lfh, sizeof(enable_lfh));
  }
#endif
}

// Enable the heap profiler if the appropriate command-line switch is
// present, bailing out of the app we can't.
void EnableHeapProfiler(const CommandLine& parsed_command_line) {
#if defined(OS_WIN)
  if (parsed_command_line.HasSwitch(switches::kMemoryProfiling))
    if (!LoadMemoryProfiler())
      exit(-1);
#endif
}

void CommonSubprocessInit() {
  // Initialize ResourceBundle which handles files loaded from external
  // sources.  The language should have been passed in to us from the
  // browser process as a command line flag.
  ResourceBundle::InitSharedInstance(std::wstring());

#if defined(OS_WIN)
  // HACK: Let Windows know that we have started.  This is needed to suppress
  // the IDC_APPSTARTING cursor from being displayed for a prolonged period
  // while a subprocess is starting.
  PostThreadMessage(GetCurrentThreadId(), WM_NULL, 0, 0);
  MSG msg;
  PeekMessage(&msg, NULL, 0, 0, PM_REMOVE);
#endif
}

}  // namespace

#if defined(OS_WIN)
DLLEXPORT int __cdecl ChromeMain(HINSTANCE instance,
                                 sandbox::SandboxInterfaceInfo* sandbox_info,
                                 TCHAR* command_line) {
#elif defined(OS_POSIX)
int ChromeMain(int argc, const char** argv) {
#endif

#if defined(OS_MACOSX)
  // If Breakpad is not present then turn off os crash dumps so we don't have
  // to wait eons for Apple's Crash Reporter to generate a dump.
  if (IsCrashReporterDisabled()) {
    DebugUtil::DisableOSCrashDumps();
  }
#endif
  RegisterInvalidParamHandler();

  // The exit manager is in charge of calling the dtors of singleton objects.
  base::AtExitManager exit_manager;

  // We need this pool for all the objects created before we get to the
  // event loop, but we don't want to leave them hanging around until the
  // app quits. Each "main" needs to flush this pool right before it goes into
  // its main event loop to get rid of the cruft.
  base::ScopedNSAutoreleasePool autorelease_pool;

#if defined(OS_POSIX)
  base::GlobalDescriptors* g_fds = Singleton<base::GlobalDescriptors>::get();
  g_fds->Set(kPrimaryIPCChannel,
             kPrimaryIPCChannel + base::GlobalDescriptors::kBaseDescriptor);
#if defined(OS_LINUX)
  g_fds->Set(kCrashDumpSignal,
             kCrashDumpSignal + base::GlobalDescriptors::kBaseDescriptor);
#endif
#endif

  // Initialize the command line.
#if defined(OS_WIN)
  CommandLine::Init(0, NULL);
#else
  CommandLine::Init(argc, argv);
#endif

#if defined(OS_MACOSX)
  // Needs to be called after CommandLine::Init().
  InitCrashProcessInfo();
#endif

  const CommandLine& parsed_command_line = *CommandLine::ForCurrentProcess();

#if defined(OS_WIN)
  // Must do this before any other usage of command line!
  if (HasDeprecatedArguments(parsed_command_line.command_line_string()))
    return 1;
#endif

  int browser_pid;
  std::wstring process_type =
    parsed_command_line.GetSwitchValue(switches::kProcessType);
  if (process_type.empty()) {
    browser_pid = base::GetCurrentProcId();
#if defined(OS_POSIX)
    // Ignore SIGPIPE so we don't crash when writing to sockets that have been
    // closed on the server end.
    struct sigaction action;
    action.sa_handler = SIG_IGN;
    sigemptyset(&action.sa_mask);
    action.sa_flags = 0;
    CHECK(sigaction(SIGPIPE, &action, 0) == 0);
#endif  // OS_POSIX
  } else {
#if defined(OS_WIN)
    std::wstring channel_name =
      parsed_command_line.GetSwitchValue(switches::kProcessChannelID);

    browser_pid = StringToInt(WideToASCII(channel_name));
    DCHECK(browser_pid != 0);
#else
    browser_pid = base::GetCurrentProcId();
#endif

#if defined(OS_POSIX)
    // When you hit Ctrl-C in a terminal running the browser
    // process, a SIGINT is delivered to the entire process group.
    // When debugging the browser process via gdb, gdb catches the
    // SIGINT for the browser process (and dumps you back to the gdb
    // console) but doesn't for the child processes, killing them.
    // The fix is to have child processes ignore SIGINT; they'll die
    // on their own when the browser process goes away.
    // Note that we *can't* rely on DebugUtil::BeingDebugged to catch this
    // case because we are the child process, which is not being debugged.
    if (!DebugUtil::BeingDebugged())
      signal(SIGINT, SIG_IGN);
#endif
  }
  SetupCRT(parsed_command_line);

  // Initialize the Chrome path provider.
  app::RegisterPathProvider();
  chrome::RegisterPathProvider();

  // Initialize the Stats Counters table.  With this initialized,
  // the StatsViewer can be utilized to read counters outside of
  // Chrome.  These lines can be commented out to effectively turn
  // counters 'off'.  The table is created and exists for the life
  // of the process.  It is not cleaned up.
  // TODO(port): we probably need to shut this down correctly to avoid
  // leaking shared memory regions on posix platforms.
  if (parsed_command_line.HasSwitch(switches::kEnableStatsTable)) {
    std::string statsfile =
        StringPrintf("%s-%d", chrome::kStatsFilename, browser_pid);
    StatsTable *stats_table = new StatsTable(statsfile,
        chrome::kStatsMaxThreads, chrome::kStatsMaxCounters);
    StatsTable::set_current(stats_table);
  }

  StatsScope<StatsCounterTimer>
      startup_timer(chrome::Counters::chrome_main());

  // Enable the heap profiler as early as possible!
  EnableHeapProfiler(parsed_command_line);

  // Enable Message Loop related state asap.
  if (parsed_command_line.HasSwitch(switches::kMessageLoopHistogrammer))
    MessageLoop::EnableHistogrammer(true);

  // Checks if the sandbox is enabled in this process and initializes it if this
  // is the case. The crash handler depends on this so it has to be done before
  // its initialization.
  SandboxInitWrapper sandbox_wrapper;
#if defined(OS_WIN)
  sandbox_wrapper.SetServices(sandbox_info);
#endif
  sandbox_wrapper.InitializeSandbox(parsed_command_line, process_type);

#if defined(OS_WIN)
  _Module.Init(NULL, instance);
#endif

  // Notice a user data directory override if any
  const std::wstring user_data_dir =
      parsed_command_line.GetSwitchValue(switches::kUserDataDir);
  if (!user_data_dir.empty())
    CHECK(PathService::Override(chrome::DIR_USER_DATA, user_data_dir));

#if defined(OS_LINUX)
  // Needs to be called after we have chrome::DIR_USER_DATA.
  InitCrashReporter();
#endif

  bool single_process =
#if defined (GOOGLE_CHROME_BUILD)
    // This is an unsupported and not fully tested mode, so don't enable it for
    // official Chrome builds.
    false;
#else
    parsed_command_line.HasSwitch(switches::kSingleProcess);
#endif
  if (single_process)
    RenderProcessHost::set_run_renderer_in_process(true);
#if defined(OS_MACOSX)
  // TODO(port-mac): This is from renderer_main_platform_delegate.cc.
  // shess tried to refactor things appropriately, but it sprawled out
  // of control because different platforms needed different styles of
  // initialization.  Try again once we understand the process
  // architecture needed and where it should live.
  if (single_process)
    InitWebCoreSystemInterface();
#endif

  bool icu_result = icu_util::Initialize();
  CHECK(icu_result);

  logging::OldFileDeletionState file_state =
      logging::APPEND_TO_OLD_LOG_FILE;
  if (process_type.empty()) {
    file_state = logging::DELETE_OLD_LOG_FILE;
  }
  logging::InitChromeLogging(parsed_command_line, file_state);

#ifdef NDEBUG
  if (parsed_command_line.HasSwitch(switches::kSilentDumpOnDCHECK) &&
      parsed_command_line.HasSwitch(switches::kEnableDCHECK)) {
#if defined(OS_WIN)
    logging::SetLogReportHandler(ChromeAssert);
#endif
  }
#endif  // NDEBUG

  if (!process_type.empty())
    CommonSubprocessInit();

  startup_timer.Stop();  // End of Startup Time Measurement.

  MainFunctionParams main_params(parsed_command_line, sandbox_wrapper,
                                 &autorelease_pool);

  // TODO(port): turn on these main() functions as they've been de-winified.
  int rv = -1;
  if (process_type == switches::kRendererProcess) {
    rv = RendererMain(main_params);
  } else if (process_type == switches::kPluginProcess) {
    rv = PluginMain(main_params);
  } else if (process_type == switches::kUtilityProcess) {
    rv = UtilityMain(main_params);
  } else if (process_type == switches::kWorkerProcess) {
#if defined(OS_WIN)
    rv = WorkerMain(main_params);
#else
    NOTIMPLEMENTED();
#endif
  } else if (process_type == switches::kZygoteProcess) {
#if defined(OS_LINUX)
    if (ZygoteMain(main_params)) {
      // Zygote::HandleForkRequest may have reallocated the command
      // line so update it here with the new version.
      const CommandLine& parsed_command_line =
        *CommandLine::ForCurrentProcess();
      MainFunctionParams main_params(parsed_command_line, sandbox_wrapper,
                                     &autorelease_pool);
      RendererMain(main_params);
    }
#else
    NOTIMPLEMENTED();
#endif
  } else if (process_type.empty()) {
#if defined(OS_LINUX)
    // Glib type system initialization. Needed at least for gconf,
    // used in net/proxy/proxy_config_service_linux.cc. Most likely
    // this is superfluous as gtk_init() ought to do this. It's
    // definitely harmless, so retained as a reminder of this
    // requirement for gconf.
    g_type_init();
    // gtk_init() can change |argc| and |argv|, but nobody else uses them.
    gtk_init(&argc, const_cast<char***>(&argv));
    SetUpGLibLogHandler();
#endif

    ScopedOleInitializer ole_initializer;
    rv = BrowserMain(main_params);
  } else {
    NOTREACHED() << "Unknown process type";
  }

  if (!process_type.empty()) {
    ResourceBundle::CleanupSharedInstance();
  }

#if defined(OS_WIN)
#ifdef _CRTDBG_MAP_ALLOC
  _CrtDumpMemoryLeaks();
#endif  // _CRTDBG_MAP_ALLOC

  _Module.Term();
#endif

  logging::CleanupChromeLogging();

  return rv;
}