chrome/renderer/render_process.cc

// 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.

#include "build/build_config.h"

#if defined(OS_WIN)
#include <windows.h>
#include <objidl.h>
#include <mlang.h>
#endif

#include "chrome/renderer/render_process.h"

#include "base/basictypes.h"
#include "base/command_line.h"
#include "base/compiler_specific.h"
#include "base/message_loop.h"
#include "base/histogram.h"
#include "base/path_service.h"
#include "base/sys_info.h"
#include "chrome/browser/net/dns_global.h"  // TODO(jar): DNS calls should be renderer specific, not including browser.
#include "chrome/common/chrome_switches.h"
#include "chrome/common/chrome_paths.h"
#include "chrome/common/ipc_channel.h"
#include "chrome/common/ipc_message_utils.h"
#include "chrome/common/render_messages.h"
#include "chrome/common/transport_dib.h"
#include "chrome/renderer/render_view.h"
#include "webkit/glue/webkit_glue.h"

// Attempts to load FFmpeg before engaging the sandbox.  Returns true if all
// libraries were loaded successfully, false otherwise.
static bool LoadFFmpeg() {
#if defined(OS_WIN)
  int path_keys[] = {
    chrome::FILE_LIBAVCODEC,
    chrome::FILE_LIBAVFORMAT,
    chrome::FILE_LIBAVUTIL
  };
  HMODULE libs[arraysize(path_keys)] = {NULL};
  for (size_t i = 0; i < arraysize(path_keys); ++i) {
    std::wstring path;
    if (!PathService::Get(path_keys[i], &path))
      break;
    libs[i] = LoadLibrary(path.c_str());
    if (!libs[i])
      break;
  }

  // Check that we loaded all libraries successfully.
  if (libs[arraysize(libs)-1])
    return true;

  // Free any loaded libraries if we weren't successful.
  for (size_t i = 0; i < arraysize(libs) && libs[i] != NULL; ++i) {
    FreeLibrary(libs[i]);
  }
  return false;
#else
  // TODO(port): Need to handle loading FFmpeg on non-Windows platforms.
  NOTIMPLEMENTED();
  return false;
#endif
}

//-----------------------------------------------------------------------------

RenderProcess::RenderProcess()
    : ChildProcess(new RenderThread()),
      ALLOW_THIS_IN_INITIALIZER_LIST(shared_mem_cache_cleaner_(
          base::TimeDelta::FromSeconds(5),
          this, &RenderProcess::ClearTransportDIBCache)),
      sequence_number_(0) {
  Init();
}

RenderProcess::RenderProcess(const std::wstring& channel_name)
    : ChildProcess(new RenderThread(channel_name)),
      ALLOW_THIS_IN_INITIALIZER_LIST(shared_mem_cache_cleaner_(
          base::TimeDelta::FromSeconds(5),
          this, &RenderProcess::ClearTransportDIBCache)),
      sequence_number_(0) {
  Init();
}

RenderProcess::~RenderProcess() {
  // TODO(port)
  // Try and limit what we pull in for our non-Win unit test bundle
#ifndef NDEBUG
  // log important leaked objects
  webkit_glue::CheckForLeaks();
#endif

  GetShutDownEvent()->Signal();

  // We need to stop the RenderThread as the clearer_factory_
  // member could be in use while the object itself is destroyed,
  // as a result of the containing RenderProcess object being destroyed.
  // This race condition causes a crash when the renderer process is shutting
  // down.
  child_thread()->Stop();
  ClearTransportDIBCache();
}

void RenderProcess::Init() {
  in_process_plugins_ = InProcessPlugins();
  in_process_gears_ = false;
  for (size_t i = 0; i < arraysize(shared_mem_cache_); ++i)
    shared_mem_cache_[i] = NULL;

#if defined(OS_WIN)
  // HACK:  See http://b/issue?id=1024307 for rationale.
  if (GetModuleHandle(L"LPK.DLL") == NULL) {
    // Makes sure lpk.dll is loaded by gdi32 to make sure ExtTextOut() works
    // when buffering into a EMF buffer for printing.
    typedef BOOL (__stdcall *GdiInitializeLanguagePack)(int LoadedShapingDLLs);
    GdiInitializeLanguagePack gdi_init_lpk =
        reinterpret_cast<GdiInitializeLanguagePack>(GetProcAddress(
            GetModuleHandle(L"GDI32.DLL"),
            "GdiInitializeLanguagePack"));
    DCHECK(gdi_init_lpk);
    if (gdi_init_lpk) {
      gdi_init_lpk(0);
    }
  }
#endif

  const CommandLine& command_line = *CommandLine::ForCurrentProcess();
  if (command_line.HasSwitch(switches::kJavaScriptFlags)) {
    webkit_glue::SetJavaScriptFlags(
      command_line.GetSwitchValue(switches::kJavaScriptFlags));
  }

  if (command_line.HasSwitch(switches::kEnableWatchdog)) {
    // TODO(JAR): Need to implement renderer IO msgloop watchdog.
  }

  if (command_line.HasSwitch(switches::kDumpHistogramsOnExit)) {
    StatisticsRecorder::set_dump_on_exit(true);
  }

  if (command_line.HasSwitch(switches::kGearsInRenderer)) {
#if defined(OS_WIN)
    in_process_gears_ = true;
    // Load gears.dll on startup so we can access it before the sandbox
    // blocks us.
    std::wstring path;
    if (PathService::Get(chrome::FILE_GEARS_PLUGIN, &path))
      LoadLibrary(path.c_str());
#else
    // TODO(port) Need to handle loading gears on non-Windows platforms
    NOTIMPLEMENTED();
#endif
  }

  if (command_line.HasSwitch(switches::kEnableVideo) && LoadFFmpeg()) {
    webkit_glue::SetMediaPlayerAvailable(true);
  }
}

bool RenderProcess::InProcessPlugins() {
  const CommandLine& command_line = *CommandLine::ForCurrentProcess();
  return command_line.HasSwitch(switches::kInProcessPlugins) ||
         command_line.HasSwitch(switches::kSingleProcess);
}

// -----------------------------------------------------------------------------
// Platform specific code for dealing with bitmap transport...

// -----------------------------------------------------------------------------
// Create a platform canvas object which renders into the given transport
// memory.
// -----------------------------------------------------------------------------
static skia::PlatformCanvas* CanvasFromTransportDIB(
    TransportDIB* dib, const gfx::Rect& rect) {
#if defined(OS_WIN)
  return new skia::PlatformCanvas(rect.width(), rect.height(), true,
                                  dib->handle());
#elif defined(OS_LINUX) || defined(OS_MACOSX)
  return new skia::PlatformCanvas(rect.width(), rect.height(), true,
                                  reinterpret_cast<uint8_t*>(dib->memory()));
#endif
}

TransportDIB* RenderProcess::CreateTransportDIB(size_t size) {
#if defined(OS_WIN) || defined(OS_LINUX)
  // Windows and Linux create transport DIBs inside the renderer
  return TransportDIB::Create(size, sequence_number_++);
#elif defined(OS_MACOSX)  // defined(OS_WIN) || defined(OS_LINUX)
  // Mac creates transport DIBs in the browser, so we need to do a sync IPC to
  // get one.
  TransportDIB::Handle handle;
  IPC::Message* msg = new ViewHostMsg_AllocTransportDIB(size, &handle);
  if (!child_thread()->Send(msg))
    return NULL;
  if (handle.fd < 0)
    return NULL;
  return TransportDIB::Map(handle);
#endif  // defined(OS_MACOSX)
}

void RenderProcess::FreeTransportDIB(TransportDIB* dib) {
  if (!dib)
    return;

#if defined(OS_MACOSX)
  // On Mac we need to tell the browser that it can drop a reference to the
  // shared memory.
  IPC::Message* msg = new ViewHostMsg_FreeTransportDIB(dib->id());
  child_thread()->Send(msg);
#endif

  delete dib;
}

// -----------------------------------------------------------------------------


skia::PlatformCanvas* RenderProcess::GetDrawingCanvas(
    TransportDIB** memory, const gfx::Rect& rect) {
  const size_t stride = skia::PlatformCanvas::StrideForWidth(rect.width());
  const size_t size = stride * rect.height();

  if (!GetTransportDIBFromCache(memory, size)) {
    *memory = CreateTransportDIB(size);
    if (!*memory)
      return false;
  }

  return CanvasFromTransportDIB(*memory, rect);
}

void RenderProcess::ReleaseTransportDIB(TransportDIB* mem) {
  if (PutSharedMemInCache(mem)) {
    shared_mem_cache_cleaner_.Reset();
    return;
  }

  FreeTransportDIB(mem);
}

bool RenderProcess::GetTransportDIBFromCache(TransportDIB** mem,
                                             size_t size) {
  // look for a cached object that is suitable for the requested size.
  for (size_t i = 0; i < arraysize(shared_mem_cache_); ++i) {
    if (shared_mem_cache_[i] &&
        size <= shared_mem_cache_[i]->size()) {
      *mem = shared_mem_cache_[i];
      shared_mem_cache_[i] = NULL;
      return true;
    }
  }

  return false;
}

int RenderProcess::FindFreeCacheSlot(size_t size) {
  // simple algorithm:
  //  - look for an empty slot to store mem, or
  //  - if full, then replace smallest entry which is smaller than |size|
  for (size_t i = 0; i < arraysize(shared_mem_cache_); ++i) {
    if (shared_mem_cache_[i] == NULL)
      return i;
  }

  size_t smallest_size = size;
  int smallest_index = -1;

  for (size_t i = 1; i < arraysize(shared_mem_cache_); ++i) {
    const size_t entry_size = shared_mem_cache_[i]->size();
    if (entry_size < smallest_size) {
      smallest_size = entry_size;
      smallest_index = i;
    }
  }

  if (smallest_index != -1) {
    FreeTransportDIB(shared_mem_cache_[smallest_index]);
    shared_mem_cache_[smallest_index] = NULL;
  }

  return smallest_index;
}

bool RenderProcess::PutSharedMemInCache(TransportDIB* mem) {
  const int slot = FindFreeCacheSlot(mem->size());
  if (slot == -1)
    return false;

  shared_mem_cache_[slot] = mem;
  return true;
}

void RenderProcess::ClearTransportDIBCache() {
  for (size_t i = 0; i < arraysize(shared_mem_cache_); ++i) {
    if (shared_mem_cache_[i]) {
      FreeTransportDIB(shared_mem_cache_[i]);
      shared_mem_cache_[i] = NULL;
    }
  }
}