// Copyright (c) 2012 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 <stddef.h>
#include <stdlib.h>

#include <memory>
#include <utility>

#include "base/bind.h"
#include "base/feature_list.h"
#include "base/message_loop/message_pump_type.h"
#include "base/metrics/histogram_macros.h"
#include "base/rand_util.h"
#include "base/run_loop.h"
#include "base/strings/string_number_conversions.h"
#include "base/strings/stringprintf.h"
#include "base/system/sys_info.h"
#include "base/task/single_thread_task_executor.h"
#include "base/task/thread_pool.h"
#include "base/threading/platform_thread.h"
#include "base/timer/hi_res_timer_manager.h"
#include "base/trace_event/trace_event.h"
#include "build/build_config.h"
#include "components/viz/service/main/viz_main_impl.h"
#include "content/common/content_constants_internal.h"
#include "content/common/content_switches_internal.h"
#include "content/common/skia_utils.h"
#include "content/gpu/gpu_child_thread.h"
#include "content/gpu/gpu_process.h"
#include "content/public/common/content_client.h"
#include "content/public/common/content_switches.h"
#include "content/public/common/main_function_params.h"
#include "content/public/common/result_codes.h"
#include "content/public/gpu/content_gpu_client.h"
#include "gpu/command_buffer/service/gpu_switches.h"
#include "gpu/config/gpu_driver_bug_list.h"
#include "gpu/config/gpu_finch_features.h"
#include "gpu/config/gpu_info_collector.h"
#include "gpu/config/gpu_preferences.h"
#include "gpu/config/gpu_switches.h"
#include "gpu/config/gpu_util.h"
#include "gpu/ipc/common/gpu_memory_buffer_support.h"
#include "gpu/ipc/service/gpu_config.h"
#include "gpu/ipc/service/gpu_init.h"
#include "gpu/ipc/service/gpu_watchdog_thread.h"
#include "media/gpu/buildflags.h"
#include "services/tracing/public/cpp/trace_startup.h"
#include "third_party/angle/src/gpu_info_util/SystemInfo.h"
#include "ui/base/ui_base_features.h"
#include "ui/events/platform/platform_event_source.h"
#include "ui/gfx/switches.h"
#include "ui/gl/gl_context.h"
#include "ui/gl/gl_implementation.h"
#include "ui/gl/gl_surface.h"
#include "ui/gl/gl_switches.h"
#include "ui/gl/gpu_switching_manager.h"
#include "ui/gl/init/gl_factory.h"

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

#if defined(OS_ANDROID)
#include "base/trace_event/memory_dump_manager.h"
#include "components/tracing/common/graphics_memory_dump_provider_android.h"
#endif

#if defined(OS_WIN)
#include "base/trace_event/trace_event_etw_export_win.h"
#include "base/win/scoped_com_initializer.h"
#include "base/win/windows_version.h"
#include "media/gpu/windows/dxva_video_decode_accelerator_win.h"
#include "media/gpu/windows/media_foundation_video_encode_accelerator_win.h"
#include "sandbox/win/src/sandbox.h"
#endif

#if defined(USE_X11)
#include "ui/base/x/x11_util.h"                          // nogncheck
#include "ui/gfx/linux/gpu_memory_buffer_support_x11.h"  // nogncheck
#include "ui/gfx/x/x11.h"                                // nogncheck
#include "ui/gfx/x/x11_switches.h"                       // nogncheck
#include "ui/gfx/x/x11_types.h"                          // nogncheck
#endif

#if defined(OS_LINUX)
#include "content/gpu/gpu_sandbox_hook_linux.h"
#include "content/public/common/sandbox_init.h"
#include "sandbox/policy/linux/sandbox_linux.h"
#endif

#if defined(OS_MACOSX)
#include "base/message_loop/message_pump_mac.h"
#include "components/metal_util/device_removal.h"
#include "components/metal_util/test_shader.h"
#include "content/public/common/content_features.h"
#include "media/gpu/mac/vt_video_decode_accelerator_mac.h"
#include "sandbox/mac/seatbelt.h"
#include "sandbox/policy/mac/sandbox_mac.h"
#endif

#if BUILDFLAG(USE_VAAPI)
#include "media/gpu/vaapi/vaapi_wrapper.h"
#endif

namespace content {

namespace {

#if defined(OS_LINUX)
bool StartSandboxLinux(gpu::GpuWatchdogThread*,
                       const gpu::GPUInfo*,
                       const gpu::GpuPreferences&);
#elif defined(OS_WIN)
bool StartSandboxWindows(const sandbox::SandboxInterfaceInfo*);
#endif

class ContentSandboxHelper : public gpu::GpuSandboxHelper {
 public:
  ContentSandboxHelper() {}
  ~ContentSandboxHelper() override {}

#if defined(OS_WIN)
  void set_sandbox_info(const sandbox::SandboxInterfaceInfo* info) {
    sandbox_info_ = info;
  }
#endif

 private:
  // SandboxHelper:
  void PreSandboxStartup() override {
    // Warm up resources that don't need access to GPUInfo.
    {
      TRACE_EVENT0("gpu", "Warm up rand");
      // Warm up the random subsystem, which needs to be done pre-sandbox on all
      // platforms.
      (void)base::RandUint64();
    }

#if BUILDFLAG(USE_VAAPI)
    media::VaapiWrapper::PreSandboxInitialization();
#endif
#if defined(OS_WIN)
    media::DXVAVideoDecodeAccelerator::PreSandboxInitialization();
    media::MediaFoundationVideoEncodeAccelerator::PreSandboxInitialization();
#endif

#if defined(OS_MACOSX)
    if (base::FeatureList::IsEnabled(features::kMacV2GPUSandbox)) {
      TRACE_EVENT0("gpu", "Initialize VideoToolbox");
      media::InitializeVideoToolbox();
    }
#endif

    // On Linux, reading system memory doesn't work through the GPU sandbox.
    // This value is cached, so access it here to populate the cache.
    base::SysInfo::AmountOfPhysicalMemory();
  }

  bool EnsureSandboxInitialized(gpu::GpuWatchdogThread* watchdog_thread,
                                const gpu::GPUInfo* gpu_info,
                                const gpu::GpuPreferences& gpu_prefs) override {
#if defined(OS_LINUX)
    return StartSandboxLinux(watchdog_thread, gpu_info, gpu_prefs);
#elif defined(OS_WIN)
    return StartSandboxWindows(sandbox_info_);
#elif defined(OS_MACOSX)
    return sandbox::Seatbelt::IsSandboxed();
#else
    return false;
#endif
  }

#if defined(OS_WIN)
  const sandbox::SandboxInterfaceInfo* sandbox_info_ = nullptr;
#endif

  DISALLOW_COPY_AND_ASSIGN(ContentSandboxHelper);
};

#if defined(OS_MACOSX)
void TestShaderCallback(metal::TestShaderComponent component,
                        metal::TestShaderResult result,
                        const base::TimeDelta& callback_time) {
  switch (result) {
    case metal::TestShaderResult::kNotAttempted:
    case metal::TestShaderResult::kFailed:
      // Don't include data if no Metal device was created (e.g, due to hardware
      // or macOS version reasons).
      return;
    case metal::TestShaderResult::kTimedOut:
      break;
    case metal::TestShaderResult::kSucceeded:
      break;
  }
  switch (component) {
    case metal::TestShaderComponent::kCompile:
      UMA_HISTOGRAM_MEDIUM_TIMES("Gpu.Metal.TestShaderCompileTime",
                                 callback_time);
      break;
    case metal::TestShaderComponent::kLink:
      UMA_HISTOGRAM_MEDIUM_TIMES("Gpu.Metal.TestShaderLinkTime", callback_time);
      break;
  }
}
#endif

}  // namespace

// Main function for starting the Gpu process.
int GpuMain(const MainFunctionParams& parameters) {
  TRACE_EVENT0("gpu", "GpuMain");
  base::trace_event::TraceLog::GetInstance()->set_process_name("GPU Process");
  base::trace_event::TraceLog::GetInstance()->SetProcessSortIndex(
      kTraceEventGpuProcessSortIndex);

  const base::CommandLine& command_line = parameters.command_line;

  gpu::GpuPreferences gpu_preferences;
  if (command_line.HasSwitch(switches::kGpuPreferences)) {
    std::string value =
        command_line.GetSwitchValueASCII(switches::kGpuPreferences);
    bool success = gpu_preferences.FromSwitchValue(value);
    CHECK(success);
  }

  if (gpu_preferences.gpu_startup_dialog)
    WaitForDebugger("Gpu");

  base::Time start_time = base::Time::Now();

#if defined(OS_WIN)
  base::trace_event::TraceEventETWExport::EnableETWExport();

  // Prevent Windows from displaying a modal dialog on failures like not being
  // able to load a DLL.
  SetErrorMode(
      SEM_FAILCRITICALERRORS |
      SEM_NOGPFAULTERRORBOX |
      SEM_NOOPENFILEERRORBOX);

  // COM is used by some Windows Media Foundation calls made on this thread and
  // must be MTA so we don't have to worry about pumping messages to handle
  // COM callbacks.
  base::win::ScopedCOMInitializer com_initializer(
      base::win::ScopedCOMInitializer::kMTA);

  if (base::FeatureList::IsEnabled(features::kGpuProcessHighPriorityWin))
    ::SetPriorityClass(::GetCurrentProcess(), ABOVE_NORMAL_PRIORITY_CLASS);
#endif

  // Installs a base::LogMessageHandlerFunction which ensures messages are sent
  // to the GpuProcessHost once the GpuServiceImpl has started.
  viz::GpuServiceImpl::InstallPreInitializeLogHandler();

  // We are experiencing what appear to be memory-stomp issues in the GPU
  // process. These issues seem to be impacting the task executor and listeners
  // registered to it. Create the task executor on the heap to guard against
  // this.
  // TODO(ericrk): Revisit this once we assess its impact on crbug.com/662802
  // and crbug.com/609252.
  std::unique_ptr<base::SingleThreadTaskExecutor> main_thread_task_executor;
  std::unique_ptr<ui::PlatformEventSource> event_source;
  if (command_line.HasSwitch(switches::kHeadless)) {
    main_thread_task_executor =
        std::make_unique<base::SingleThreadTaskExecutor>(
            base::MessagePumpType::DEFAULT);
  } else {
#if defined(OS_WIN)
    // The GpuMain thread should not be pumping Windows messages because no UI
    // is expected to run on this thread.
    main_thread_task_executor =
        std::make_unique<base::SingleThreadTaskExecutor>(
            base::MessagePumpType::DEFAULT);
#elif defined(USE_X11) || defined(USE_OZONE)
#if defined(USE_X11)
    if (!features::IsUsingOzonePlatform()) {
      // We need a UI loop so that we can grab the Expose events. See
      // GLSurfaceGLX and https://crbug.com/326995.
      ui::SetDefaultX11ErrorHandlers();
      if (!gfx::GetXDisplay())
        return RESULT_CODE_GPU_DEAD_ON_ARRIVAL;
      main_thread_task_executor =
          std::make_unique<base::SingleThreadTaskExecutor>(
              base::MessagePumpType::UI);
      event_source = ui::PlatformEventSource::CreateDefault();
    }
#endif
#if defined(USE_OZONE)
    // The MessagePump type required depends on the Ozone platform selected at
    // runtime.
    if (!main_thread_task_executor) {
      main_thread_task_executor =
          std::make_unique<base::SingleThreadTaskExecutor>(
              gpu_preferences.message_pump_type);
    }
#endif
#elif defined(OS_LINUX)
#error "Unsupported Linux platform."
#elif defined(OS_MACOSX)
    // Cross-process CoreAnimation requires a CFRunLoop to function at all, and
    // requires a NSRunLoop to not starve under heavy load. See:
    // https://crbug.com/312462#c51 and https://crbug.com/783298
    main_thread_task_executor =
        std::make_unique<base::SingleThreadTaskExecutor>(
            base::MessagePumpType::NS_RUNLOOP);
    // As part of the migration to DoWork(), this policy is required to keep
    // previous behavior and avoid regressions.
    // TODO(crbug.com/1041853): Consider updating the policy.
    main_thread_task_executor->SetWorkBatchSize(2);
#else
    main_thread_task_executor =
        std::make_unique<base::SingleThreadTaskExecutor>(
            base::MessagePumpType::DEFAULT);
#endif
  }

  base::PlatformThread::SetName("CrGpuMain");

#if !defined(OS_MACOSX)
  if (base::FeatureList::IsEnabled(features::kGpuUseDisplayThreadPriority)) {
    // Set thread priority before sandbox initialization.
    base::PlatformThread::SetCurrentThreadPriority(
        base::ThreadPriority::DISPLAY);
  }
#endif

  auto gpu_init = std::make_unique<gpu::GpuInit>();
  ContentSandboxHelper sandbox_helper;
#if defined(OS_WIN)
  sandbox_helper.set_sandbox_info(parameters.sandbox_info);
#endif

  gpu_init->set_sandbox_helper(&sandbox_helper);

  // Since GPU initialization calls into skia, it's important to initialize skia
  // before it.
  InitializeSkia();

  // Create the ThreadPool before invoking |gpu_init| as it needs the ThreadPool
  // (in angle::InitializePlatform()). Do not start it until after the sandbox
  // is initialized however to avoid creating threads outside the sandbox.
  base::ThreadPoolInstance::Create("GPU");

  // Gpu initialization may fail for various reasons, in which case we will need
  // to tear down this process. However, we can not do so safely until the IPC
  // channel is set up, because the detection of early return of a child process
  // is implemented using an IPC channel error. If the IPC channel is not fully
  // set up between the browser and GPU process, and the GPU process crashes or
  // exits early, the browser process will never detect it.  For this reason we
  // defer tearing down the GPU process until receiving the initialization
  // message from the browser (through mojom::VizMain::CreateGpuService()).
  const bool init_success = gpu_init->InitializeAndStartSandbox(
      const_cast<base::CommandLine*>(&command_line), gpu_preferences);
  const bool dead_on_arrival = !init_success;

  GetContentClient()->SetGpuInfo(gpu_init->gpu_info());

  // Start the ThreadPoolInstance now that the sandbox is initialized.
  base::ThreadPoolInstance::Get()->StartWithDefaultParams();

  const base::ThreadPriority io_thread_priority =
      base::FeatureList::IsEnabled(features::kGpuUseDisplayThreadPriority)
          ? base::ThreadPriority::DISPLAY
          : base::ThreadPriority::NORMAL;
#if defined(OS_MACOSX)
  // Increase the thread priority to get more reliable values in performance
  // test of mac_os.
  GpuProcess gpu_process(
      (command_line.HasSwitch(switches::kUseHighGPUThreadPriorityForPerfTests)
           ? base::ThreadPriority::REALTIME_AUDIO
           : io_thread_priority));
#else
  GpuProcess gpu_process(io_thread_priority);
#endif

#if defined(USE_X11)
  // ui::GbmDevice() takes >50ms with amdgpu, so kick off
  // GpuMemoryBufferSupportX11 creation on another thread now.
  if (!features::IsUsingOzonePlatform() &&
      gpu_preferences.enable_native_gpu_memory_buffers) {
    base::ThreadPool::PostTask(
        FROM_HERE, base::BindOnce([]() {
          SCOPED_UMA_HISTOGRAM_TIMER("Linux.X11.GbmSupportX11CreationTime");
          ui::GpuMemoryBufferSupportX11::GetInstance();
        }));
  }
#endif

  auto* client = GetContentClient()->gpu();
  if (client)
    client->PostIOThreadCreated(gpu_process.io_task_runner());

  base::RunLoop run_loop;
  GpuChildThread* child_thread =
      new GpuChildThread(run_loop.QuitClosure(), std::move(gpu_init));
  child_thread->Init(start_time);

  gpu_process.set_main_thread(child_thread);

#if defined(OS_POSIX) && !defined(OS_ANDROID) && !defined(OS_MACOSX)
  // Startup tracing is usually enabled earlier, but if we forked from a zygote,
  // we can only enable it after mojo IPC support is brought up initialized by
  // GpuChildThread, because the mojo broker has to create the tracing SMB on
  // our behalf due to the zygote sandbox.
  if (parameters.zygote_child)
    tracing::EnableStartupTracingIfNeeded();
#endif  // OS_POSIX && !OS_ANDROID && !!OS_MACOSX

#if defined(OS_MACOSX)
  // A GPUEjectPolicy of 'wait' is set in the Info.plist of the browser
  // process, meaning it is "responsible" for making sure it and its
  // subordinate processes (i.e. the GPU process) drop references to the
  // external GPU. Despite this, the system still sends the device removal
  // notifications to the GPU process, so the GPU process handles its own
  // graceful shutdown without help from the browser process.
  //
  // Using the "SafeEjectGPU" tool, we can see that when the browser process
  // has a policy of 'wait', the GPU process gets the 'rwait' policy: "Eject
  // actions apply to the responsible process, who in turn deals with
  // subordinates to eliminate their ejecting eGPU references" [man 8
  // SafeEjectGPU]. Empirically, the browser does not relaunch. Once the GPU
  // process exits, it appears that the browser process is no longer considered
  // to be using the GPU, so it "succeeds" the 'wait'.
  metal::RegisterGracefulExitOnDeviceRemoval();

  // Launch a test metal shader compile to see how long it takes to complete (if
  // it ever completes).
  // https://crbug.com/974219
  metal::TestShader(base::BindOnce(TestShaderCallback));
#endif

#if defined(OS_ANDROID)
  base::trace_event::MemoryDumpManager::GetInstance()->RegisterDumpProvider(
      tracing::GraphicsMemoryDumpProvider::GetInstance(), "AndroidGraphics",
      nullptr);
#endif

  base::HighResolutionTimerManager hi_res_timer_manager;

  {
    TRACE_EVENT0("gpu", "Run Message Loop");
    run_loop.Run();
  }

  return dead_on_arrival ? RESULT_CODE_GPU_DEAD_ON_ARRIVAL : 0;
}

namespace {

#if defined(OS_LINUX)
bool StartSandboxLinux(gpu::GpuWatchdogThread* watchdog_thread,
                       const gpu::GPUInfo* gpu_info,
                       const gpu::GpuPreferences& gpu_prefs) {
  TRACE_EVENT0("gpu,startup", "Initialize sandbox");

  if (watchdog_thread) {
    // SandboxLinux needs to be able to ensure that the thread
    // has really been stopped.
    sandbox::policy::SandboxLinux::GetInstance()->StopThread(watchdog_thread);
  }

  // SandboxLinux::InitializeSandbox() must always be called
  // with only one thread.
  sandbox::policy::SandboxLinux::Options sandbox_options;
  sandbox_options.use_amd_specific_policies =
      gpu_info && angle::IsAMD(gpu_info->active_gpu().vendor_id);
  sandbox_options.use_intel_specific_policies =
      gpu_info && angle::IsIntel(gpu_info->active_gpu().vendor_id);
  sandbox_options.accelerated_video_decode_enabled =
      !gpu_prefs.disable_accelerated_video_decode;
  sandbox_options.accelerated_video_encode_enabled =
      !gpu_prefs.disable_accelerated_video_encode;

  bool res = sandbox::policy::SandboxLinux::GetInstance()->InitializeSandbox(
      sandbox::policy::SandboxTypeFromCommandLine(
          *base::CommandLine::ForCurrentProcess()),
      base::BindOnce(GpuProcessPreSandboxHook), sandbox_options);

  if (watchdog_thread) {
    base::Thread::Options thread_options;
    thread_options.timer_slack = base::TIMER_SLACK_MAXIMUM;
    watchdog_thread->StartWithOptions(thread_options);
  }

  return res;
}
#endif  // defined(OS_LINUX)

#if defined(OS_WIN)
bool StartSandboxWindows(const sandbox::SandboxInterfaceInfo* sandbox_info) {
  TRACE_EVENT0("gpu,startup", "Lower token");

  // For Windows, if the target_services interface is not zero, the process
  // is sandboxed and we must call LowerToken() before rendering untrusted
  // content.
  sandbox::TargetServices* target_services = sandbox_info->target_services;
  if (target_services) {
    target_services->LowerToken();
    return true;
  }

  return false;
}
#endif  // defined(OS_WIN)

}  // namespace.

}  // namespace content