command_buffer_gles2: Implement EGL default Display as a global object

gpu/gles2_conform_support/egl/display.cc

 // 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 "gpu/gles2_conform_support/egl/display.h"
 
-#include <stddef.h>
-#include <stdint.h>
+#include "gpu/gles2_conform_support/egl/config.h"
+#include "gpu/gles2_conform_support/egl/context.h"
+#include "gpu/gles2_conform_support/egl/surface.h"
+#include "gpu/gles2_conform_support/egl/thread_state.h"
 
-#include <vector>
-#include "base/at_exit.h"
-#include "base/bind.h"
-#include "base/bind_helpers.h"
-#include "base/lazy_instance.h"
-#include "gpu/command_buffer/client/gles2_implementation.h"
-#include "gpu/command_buffer/client/gles2_lib.h"
-#include "gpu/command_buffer/client/transfer_buffer.h"
-#include "gpu/command_buffer/common/value_state.h"
-#include "gpu/command_buffer/service/context_group.h"
-#include "gpu/command_buffer/service/mailbox_manager.h"
-#include "gpu/command_buffer/service/memory_tracking.h"
-#include "gpu/command_buffer/service/transfer_buffer_manager.h"
-#include "gpu/command_buffer/service/valuebuffer_manager.h"
-#include "gpu/gles2_conform_support/egl/config.h"
-#include "gpu/gles2_conform_support/egl/surface.h"
-#include "gpu/gles2_conform_support/egl/test_support.h"
+namespace egl {
 
-namespace {
-const int32_t kCommandBufferSize = 1024 * 1024;
-const int32_t kTransferBufferSize = 512 * 1024;
+Display::Display()
+    : is_initialized_(false),
+      next_create_window_surface_creates_pbuffer_(false),
+      window_surface_pbuffer_width_(0),
+      window_surface_pbuffer_height_(0) {}
+
+Display::~Display() {
+  surfaces_.clear();
+  contexts_.clear();
+}
+void Display::SetNextCreateWindowSurfaceCreatesPBuffer(EGLint width,
+                                                       EGLint height) {
+  next_create_window_surface_creates_pbuffer_ = true;
+  window_surface_pbuffer_width_ = width;
+  window_surface_pbuffer_height_ = height;
 }
 
-namespace egl {
-#if defined(COMMAND_BUFFER_GLES_LIB_SUPPORT_ONLY)
-// egl::Display is used for comformance tests and command_buffer_gles.  We only
-// need the exit manager for the command_buffer_gles library.
-// TODO(hendrikw): Find a cleaner solution for this.
-namespace {
-base::LazyInstance<base::Lock>::Leaky g_exit_manager_lock;
-int g_exit_manager_use_count;
-base::AtExitManager* g_exit_manager;
-void RefAtExitManager() {
-  base::AutoLock lock(g_exit_manager_lock.Get());
-#if defined(COMPONENT_BUILD)
-  if (g_command_buffer_gles_has_atexit_manager) {
-    return;
-  }
-#endif
-  if (g_exit_manager_use_count == 0) {
-    g_exit_manager = new base::AtExitManager;
-  }
-  ++g_exit_manager_use_count;
+EGLBoolean Display::Initialize(ThreadState* ts, EGLint* major, EGLint* minor) {
+  base::AutoLock auto_lock(lock_);
+  is_initialized_ = true;
+
+  if (major)
+    *major = 1;
+  if (minor)
+    *minor = 4;
+  return ts->ReturnSuccess(EGL_TRUE);
 }
-void ReleaseAtExitManager() {
-  base::AutoLock lock(g_exit_manager_lock.Get());
-#if defined(COMPONENT_BUILD)
-  if (g_command_buffer_gles_has_atexit_manager) {
-    return;
-  }
-#endif
-  --g_exit_manager_use_count;
-  if (g_exit_manager_use_count == 0) {
-    delete g_exit_manager;
-    g_exit_manager = nullptr;
+
+EGLBoolean Display::Terminate(ThreadState* ts) {
+  base::AutoLock auto_lock(lock_);
+  is_initialized_ = false;
+  surfaces_.clear();
+  for (const auto& context : contexts_)
+    context->MarkDestroyed();
+  contexts_.clear();
+  return ts->ReturnSuccess(EGL_TRUE);
+}
+
+const char* Display::QueryString(ThreadState* ts, EGLint name) {
+  base::AutoLock auto_lock(lock_);
+  if (!is_initialized_)
+    return ts->ReturnError<const char*>(EGL_NOT_INITIALIZED, nullptr);
+  switch (name) {
+    case EGL_CLIENT_APIS:
+      return ts->ReturnSuccess("OpenGL_ES");
+    case EGL_EXTENSIONS:
+      return ts->ReturnSuccess("");
+    case EGL_VENDOR:
+      return ts->ReturnSuccess("Google Inc.");
+    case EGL_VERSION:
+      return ts->ReturnSuccess("1.4");
+    default:
+      return ts->ReturnError<const char*>(EGL_BAD_PARAMETER, nullptr);
   }
 }
-}
-#endif
 
-Display::Display(EGLNativeDisplayType display_id)
-    : display_id_(display_id),
-      is_initialized_(false),
-      create_offscreen_(false),
-      create_offscreen_width_(0),
-      create_offscreen_height_(0),
-      next_fence_sync_release_(1) {
-#if defined(COMMAND_BUFFER_GLES_LIB_SUPPORT_ONLY)
-  RefAtExitManager();
-#endif
+EGLBoolean Display::ChooseConfig(ThreadState* ts,
+                                 const EGLint* attrib_list,
+                                 EGLConfig* configs,
+                                 EGLint config_size,
+                                 EGLint* num_config) {
+  base::AutoLock auto_lock(lock_);
+  if (!is_initialized_)
+    return ts->ReturnError(EGL_NOT_INITIALIZED, EGL_FALSE);
+  if (num_config == nullptr)
+    return ts->ReturnError(EGL_BAD_PARAMETER, EGL_FALSE);
+  if (!Config::ValidateAttributeList(attrib_list))
+    return ts->ReturnError(EGL_BAD_ATTRIBUTE, EGL_FALSE);
+  InitializeConfigsIfNeeded();
+  if (!configs)
+    config_size = 0;
+  *num_config = 0;
+  for (size_t i = 0; i < arraysize(configs_); ++i) {
+    if (configs_[i]->Matches(attrib_list)) {
+      if (*num_config < config_size) {
+        configs[*num_config] = configs_[i].get();
+      }
+      ++*num_config;
+    }
+  }
+  return ts->ReturnSuccess(EGL_TRUE);
 }
 
-Display::~Display() {
-  gles2::Terminate();
-#if defined(COMMAND_BUFFER_GLES_LIB_SUPPORT_ONLY)
-  ReleaseAtExitManager();
-#endif
-}
-
-bool Display::Initialize() {
-  gles2::Initialize();
-  is_initialized_ = true;
-  return true;
-}
-
-bool Display::IsValidConfig(EGLConfig config) {
-  return (config != NULL) && (config == config_.get());
-}
-
-bool Display::ChooseConfigs(EGLConfig* configs,
-                            EGLint config_size,
-                            EGLint* num_config) {
-  // TODO(alokp): Find out a way to find all configs. CommandBuffer currently
-  // does not support finding or choosing configs.
-  *num_config = 1;
-  if (configs != NULL) {
-    if (config_ == NULL) {
-      config_.reset(new Config);
-    }
-    configs[0] = config_.get();
-  }
-  return true;
-}
-
-bool Display::GetConfigs(EGLConfig* configs,
-                         EGLint config_size,
-                         EGLint* num_config) {
-  // TODO(alokp): Find out a way to find all configs. CommandBuffer currently
-  // does not support finding or choosing configs.
-  *num_config = 1;
-  if (configs != NULL) {
-    if (config_ == NULL) {
-      config_.reset(new Config);
-    }
-    configs[0] = config_.get();
-  }
-  return true;
-}
-
-bool Display::GetConfigAttrib(EGLConfig config,
-                              EGLint attribute,
-                              EGLint* value) {
-  const egl::Config* cfg = static_cast<egl::Config*>(config);
-  return cfg->GetAttrib(attribute, value);
+EGLBoolean Display::GetConfigs(ThreadState* ts,
+                               EGLConfig* configs,
+                               EGLint config_size,
+                               EGLint* num_config) {
+  base::AutoLock auto_lock(lock_);
+  if (!is_initialized_)
+    return ts->ReturnError(EGL_NOT_INITIALIZED, EGL_FALSE);
+  if (num_config == nullptr)
+    return ts->ReturnError(EGL_BAD_PARAMETER, EGL_FALSE);
+  InitializeConfigsIfNeeded();
+  if (!configs)
+    config_size = 0;
+  *num_config = arraysize(configs_);
+  size_t count =
+      std::min(arraysize(configs_), static_cast<size_t>(config_size));
+  for (size_t i = 0; i < count; ++i)
+    configs[i] = configs_[i].get();
+  return ts->ReturnSuccess(EGL_TRUE);
 }
 
 bool Display::IsValidNativeWindow(EGLNativeWindowType win) {
 #if defined OS_WIN
   return ::IsWindow(win) != FALSE;
 #else
   // TODO(alokp): Validate window handle.
   return true;
 #endif  // OS_WIN
 }
 
-bool Display::IsValidSurface(EGLSurface surface) {
-  return (surface != NULL) && (surface == surface_.get());
-}
-
-EGLSurface Display::CreateWindowSurface(EGLConfig config,
+EGLBoolean Display::GetConfigAttrib(ThreadState* ts,
+                                    EGLConfig cfg,
+                                    EGLint attribute,
+                                    EGLint* value) {
+  base::AutoLock auto_lock(lock_);
+  if (!is_initialized_)
+    return ts->ReturnError(EGL_NOT_INITIALIZED, EGL_FALSE);
+  const egl::Config* config = GetConfig(cfg);
+  if (!config)
+    return ts->ReturnError(EGL_BAD_CONFIG, EGL_FALSE);
+  if (!config->GetAttrib(attribute, value))
+    return ts->ReturnError(EGL_BAD_ATTRIBUTE, EGL_FALSE);
+  return ts->ReturnSuccess(EGL_TRUE);
+}
+
+EGLSurface Display::CreatePbufferSurface(ThreadState* ts,
+                                         EGLConfig cfg,
+                                         const EGLint* attrib_list) {
+  base::AutoLock auto_lock(lock_);
+  if (!is_initialized_)
+    return ts->ReturnError(EGL_NOT_INITIALIZED, EGL_NO_SURFACE);
+  const egl::Config* config = GetConfig(cfg);
+  if (!config)
+    return ts->ReturnError(EGL_BAD_CONFIG, EGL_NO_SURFACE);
+  EGLint value = EGL_NONE;
+  config->GetAttrib(EGL_SURFACE_TYPE, &value);
+  if ((value & EGL_PBUFFER_BIT) == 0)
+    return ts->ReturnError(EGL_BAD_MATCH, EGL_NO_SURFACE);
+  if (!egl::Surface::ValidatePbufferAttributeList(attrib_list))
+    return ts->ReturnError(EGL_BAD_ATTRIBUTE, EGL_NO_SURFACE);
+
+  int width = 1;
+  int height = 1;
+  if (attrib_list) {
+    for (const int32_t* attr = attrib_list; attr[0] != EGL_NONE; attr += 2) {
+      switch (attr[0]) {
+        case EGL_WIDTH:
+          width = attr[1];
+          break;
+        case EGL_HEIGHT:
+          height = attr[1];
+          break;
+      }
+    }
+  }
+  return DoCreatePbufferSurface(ts, width, height);
+}
+
+EGLSurface Display::DoCreatePbufferSurface(ThreadState* ts,
+                                           EGLint width,
+                                           EGLint height) {
+  lock_.AssertAcquired();
+  scoped_refptr<gfx::GLSurface> gl_surface;
+  gl_surface =
+      gfx::GLSurface::CreateOffscreenGLSurface(gfx::Size(width, height));
+  if (!gl_surface)
+    return ts->ReturnError(EGL_BAD_ALLOC, nullptr);
+  surfaces_.emplace_back(new Surface(gl_surface.get()));
+  return ts->ReturnSuccess<EGLSurface>(surfaces_.back().get());
+}
+
+EGLSurface Display::CreateWindowSurface(ThreadState* ts,
+                                        EGLConfig cfg,
                                         EGLNativeWindowType win,
                                         const EGLint* attrib_list) {
-  if (surface_ != NULL) {
-    // We do not support more than one window surface.
-    return EGL_NO_SURFACE;
-  }
-
-  {
-    gpu::TransferBufferManager* manager =
-        new gpu::TransferBufferManager(nullptr);
-    transfer_buffer_manager_ = manager;
-    manager->Initialize();
-  }
-  scoped_ptr<gpu::CommandBufferService> command_buffer(
-      new gpu::CommandBufferService(transfer_buffer_manager_.get()));
-  if (!command_buffer->Initialize())
-    return NULL;
-
-  scoped_refptr<gpu::gles2::ContextGroup> group(new gpu::gles2::ContextGroup(
-      gpu_preferences_, NULL, NULL,
-      new gpu::gles2::ShaderTranslatorCache(gpu_preferences_),
-      new gpu::gles2::FramebufferCompletenessCache, NULL, NULL, NULL, true));
-
-  decoder_.reset(gpu::gles2::GLES2Decoder::Create(group.get()));
-  if (!decoder_.get())
-    return EGL_NO_SURFACE;
-
-  executor_.reset(
-      new gpu::CommandExecutor(command_buffer.get(), decoder_.get(), NULL));
-
-  decoder_->set_engine(executor_.get());
-  gfx::Size size(create_offscreen_width_, create_offscreen_height_);
-  if (create_offscreen_) {
-    gl_surface_ = gfx::GLSurface::CreateOffscreenGLSurface(size);
-    create_offscreen_ = false;
-    create_offscreen_width_ = 0;
-    create_offscreen_height_ = 0;
-  } else {
-    gl_surface_ = gfx::GLSurface::CreateViewGLSurface(win);
-  }
-  if (!gl_surface_.get())
-    return EGL_NO_SURFACE;
-
-  gl_context_ = gfx::GLContext::CreateGLContext(NULL,
-                                                gl_surface_.get(),
-                                                gfx::PreferDiscreteGpu);
-  if (!gl_context_.get())
-    return EGL_NO_SURFACE;
-
-  gl_context_->MakeCurrent(gl_surface_.get());
-
-  EGLint depth_size = 0;
-  EGLint alpha_size = 0;
-  EGLint stencil_size = 0;
-  GetConfigAttrib(config, EGL_DEPTH_SIZE, &depth_size);
-  GetConfigAttrib(config, EGL_ALPHA_SIZE, &alpha_size);
-  GetConfigAttrib(config, EGL_STENCIL_SIZE, &stencil_size);
-  std::vector<int32_t> attribs;
-  attribs.push_back(EGL_DEPTH_SIZE);
-  attribs.push_back(depth_size);
-  attribs.push_back(EGL_ALPHA_SIZE);
-  attribs.push_back(alpha_size);
-  attribs.push_back(EGL_STENCIL_SIZE);
-  attribs.push_back(stencil_size);
-  // TODO(gman): Insert attrib_list. Although ES 1.1 says it must be null
-  attribs.push_back(EGL_NONE);
-
-  if (!decoder_->Initialize(gl_surface_.get(),
-                            gl_context_.get(),
-                            gl_surface_->IsOffscreen(),
-                            size,
-                            gpu::gles2::DisallowedFeatures(),
-                            attribs)) {
-    return EGL_NO_SURFACE;
-  }
-
-  command_buffer->SetPutOffsetChangeCallback(base::Bind(
-      &gpu::CommandExecutor::PutChanged, base::Unretained(executor_.get())));
-  command_buffer->SetGetBufferChangeCallback(base::Bind(
-      &gpu::CommandExecutor::SetGetBuffer, base::Unretained(executor_.get())));
-
-  scoped_ptr<gpu::gles2::GLES2CmdHelper> cmd_helper(
-      new gpu::gles2::GLES2CmdHelper(command_buffer.get()));
-  if (!cmd_helper->Initialize(kCommandBufferSize))
-    return NULL;
-
-  scoped_ptr<gpu::TransferBuffer> transfer_buffer(new gpu::TransferBuffer(
-      cmd_helper.get()));
-
-  command_buffer_.reset(command_buffer.release());
-  transfer_buffer_.reset(transfer_buffer.release());
-  gles2_cmd_helper_.reset(cmd_helper.release());
-  surface_.reset(new Surface(win));
-
-  return surface_.get();
-}
-
-void Display::DestroySurface(EGLSurface surface) {
-  DCHECK(IsValidSurface(surface));
-  executor_.reset();
-  if (decoder_.get()) {
-    decoder_->Destroy(true);
-  }
-  decoder_.reset();
-  gl_surface_ = NULL;
-  gl_context_ = NULL;
-  surface_.reset();
-}
-
-void Display::SwapBuffers(EGLSurface surface) {
-  DCHECK(IsValidSurface(surface));
-  context_->SwapBuffers();
-}
-
-bool Display::IsValidContext(EGLContext ctx) {
-  return (ctx != NULL) && (ctx == context_.get());
-}
-
-EGLContext Display::CreateContext(EGLConfig config,
+  base::AutoLock auto_lock(lock_);
+  if (!is_initialized_)
+    return ts->ReturnError(EGL_NOT_INITIALIZED, EGL_NO_SURFACE);
+  const egl::Config* config = GetConfig(cfg);
+  if (!config)
+    return ts->ReturnError(EGL_BAD_CONFIG, EGL_NO_SURFACE);
+  EGLint value = EGL_NONE;
+  config->GetAttrib(EGL_SURFACE_TYPE, &value);
+  if ((value & EGL_WINDOW_BIT) == 0)
+    return ts->ReturnError(EGL_BAD_CONFIG, EGL_NO_SURFACE);
+  if (!next_create_window_surface_creates_pbuffer_ && !IsValidNativeWindow(win))
+    return ts->ReturnError(EGL_BAD_NATIVE_WINDOW, EGL_NO_SURFACE);
+  if (!Surface::ValidateWindowAttributeList(attrib_list))
+    return ts->ReturnError(EGL_BAD_ATTRIBUTE, EGL_NO_SURFACE);
+  if (next_create_window_surface_creates_pbuffer_) {
+    next_create_window_surface_creates_pbuffer_ = false;
+    window_surface_pbuffer_width_ = 0;
+    window_surface_pbuffer_height_ = 0;
+    return DoCreatePbufferSurface(ts, window_surface_pbuffer_width_,
+                                  window_surface_pbuffer_height_);
+  }
+  scoped_refptr<gfx::GLSurface> gl_surface;
+  gl_surface = gfx::GLSurface::CreateViewGLSurface(win);
+  if (!gl_surface)
+    return ts->ReturnError(EGL_BAD_ALLOC, EGL_NO_SURFACE);
+  surfaces_.emplace_back(new Surface(gl_surface.get()));
+  return ts->ReturnSuccess(surfaces_.back().get());
+}
+
+EGLBoolean Display::DestroySurface(ThreadState* ts, EGLSurface sfe) {
+  base::AutoLock auto_lock(lock_);
+  if (!is_initialized_)
+    return ts->ReturnError(EGL_NOT_INITIALIZED, EGL_FALSE);
+  auto it = std::find(surfaces_.begin(), surfaces_.end(), sfe);
+  if (it == surfaces_.end())
+    return ts->ReturnError(EGL_BAD_SURFACE, EGL_FALSE);
+  surfaces_.erase(it);
+  return ts->ReturnSuccess(EGL_TRUE);
+}
+
+EGLBoolean Display::ReleaseCurrent(ThreadState* ts) {
+  base::AutoLock auto_lock(lock_);
+  if (!is_initialized_)
+    return ts->ReturnSuccess(EGL_TRUE);
+  ThreadState::AutoCurrentContextRestore accr(ts);
+  if (ts->current_context()) {
+    Context::MakeCurrent(ts->current_context(),
+                         ts->current_surface()->gl_surface(), nullptr, nullptr);
+    accr.SetCurrent(nullptr, nullptr);
+  }
+  return ts->ReturnSuccess(EGL_TRUE);
+}
+
+EGLBoolean Display::MakeCurrent(ThreadState* ts,
+                                EGLSurface draw,
+                                EGLSurface read,
+                                EGLSurface ctx) {
+  base::AutoLock auto_lock(lock_);
+  if (!is_initialized_)
+    return ts->ReturnError(EGL_NOT_INITIALIZED, EGL_FALSE);
+  ThreadState::AutoCurrentContextRestore accr(ts);
+  // Client might have called use because it changed some other gl binding
+  // global state. For example, the client might have called eglMakeCurrent on
+  // the same EGL as what command buffer uses. The client probably knows that
+  // this invalidates the internal state of command buffer, too. So reset the
+  // current context with accr in any case, regardless whether context or
+  // surface pointer changes.
+  Surface* new_surface = GetSurface(draw);
+  if (!new_surface)
+    return ts->ReturnError(EGL_BAD_SURFACE, EGL_FALSE);
+  new_surface = GetSurface(read);
+  if (!new_surface)
+    return ts->ReturnError(EGL_BAD_SURFACE, EGL_FALSE);
+  egl::Context* new_context = GetContext(ctx);
+  if (!new_context)
+    return ts->ReturnError(EGL_BAD_CONTEXT, EGL_FALSE);
+  if (draw != read)
+    return ts->ReturnError(EGL_BAD_MATCH, EGL_FALSE);
+
+  Surface* current_surface = ts->current_surface();
+  Context* current_context = ts->current_context();
+
+  if (current_context != new_context &&
+      new_context->is_current_in_some_thread())
+    return ts->ReturnError(EGL_BAD_ACCESS, EGL_FALSE);
+
+  if (current_surface != new_surface &&
+      new_surface->is_current_in_some_thread())
+    return ts->ReturnError(EGL_BAD_ACCESS, EGL_FALSE);
+
+  if (!Context::MakeCurrent(
+          current_context,
+          current_context ? current_surface->gl_surface() : nullptr,
+          new_context, new_context ? new_surface->gl_surface() : nullptr))
+    return ts->ReturnError(EGL_BAD_MATCH, EGL_FALSE);
+
+  accr.SetCurrent(new_surface, new_context);
+  return ts->ReturnSuccess(EGL_TRUE);
+}
+
+EGLBoolean Display::SwapBuffers(ThreadState* ts, EGLSurface sfe) {
+  base::AutoLock auto_lock(lock_);
+  if (!is_initialized_)
+    return ts->ReturnError(EGL_NOT_INITIALIZED, EGL_FALSE);
+  egl::Surface* surface = GetSurface(sfe);
+  if (!surface)
+    return ts->ReturnError(EGL_BAD_SURFACE, EGL_FALSE);
+  if (ts->current_surface() != surface)
+    return ts->ReturnError(EGL_BAD_SURFACE, EGL_FALSE);
+  ts->current_context()->FlushAndSwapBuffers(surface->gl_surface());
+  return ts->ReturnSuccess(EGL_TRUE);
+}
+
+EGLContext Display::CreateContext(ThreadState* ts,
+                                  EGLConfig cfg,
                                   EGLContext share_ctx,
                                   const EGLint* attrib_list) {
-  DCHECK(IsValidConfig(config));
-  // TODO(alokp): Add support for shared contexts.
-  if (share_ctx != NULL)
-    return EGL_NO_CONTEXT;
-
-  DCHECK(command_buffer_ != NULL);
-  DCHECK(transfer_buffer_.get());
-
-  bool bind_generates_resources = true;
-  bool lose_context_when_out_of_memory = false;
-  bool support_client_side_arrays = true;
-
-  context_.reset(
-      new gpu::gles2::GLES2Implementation(gles2_cmd_helper_.get(),
-                                          NULL,
-                                          transfer_buffer_.get(),
-                                          bind_generates_resources,
-                                          lose_context_when_out_of_memory,
-                                          support_client_side_arrays,
-                                          this));
-
-  if (!context_->Initialize(
-      kTransferBufferSize,
-      kTransferBufferSize / 2,
-      kTransferBufferSize * 2,
-      gpu::gles2::GLES2Implementation::kNoLimit)) {
-    return EGL_NO_CONTEXT;
-  }
-
-  context_->EnableFeatureCHROMIUM("pepper3d_allow_buffers_on_multiple_targets");
-  context_->EnableFeatureCHROMIUM("pepper3d_support_fixed_attribs");
-
-  return context_.get();
-}
-
-void Display::DestroyContext(EGLContext ctx) {
-  DCHECK(IsValidContext(ctx));
-  context_.reset();
-  transfer_buffer_.reset();
-}
-
-bool Display::MakeCurrent(EGLSurface draw, EGLSurface read, EGLContext ctx) {
-  if (ctx == EGL_NO_CONTEXT) {
-    gles2::SetGLContext(NULL);
-  } else {
-    DCHECK(IsValidSurface(draw));
-    DCHECK(IsValidSurface(read));
-    DCHECK(IsValidContext(ctx));
-    gles2::SetGLContext(context_.get());
-    gl_context_->MakeCurrent(gl_surface_.get());
-  }
-  return true;
-}
-
-gpu::Capabilities Display::GetCapabilities() {
-  return decoder_->GetCapabilities();
-}
-
-int32_t Display::CreateImage(ClientBuffer buffer,
-                             size_t width,
-                             size_t height,
-                             unsigned internalformat) {
-  NOTIMPLEMENTED();
-  return -1;
-}
-
-void Display::DestroyImage(int32_t id) {
-  NOTIMPLEMENTED();
-}
-
-int32_t Display::CreateGpuMemoryBufferImage(size_t width,
-                                            size_t height,
-                                            unsigned internalformat,
-                                            unsigned usage) {
-  NOTIMPLEMENTED();
-  return -1;
-}
-
-void Display::SignalQuery(uint32_t query, const base::Closure& callback) {
-  NOTIMPLEMENTED();
-}
-
-void Display::SetLock(base::Lock*) {
-  NOTIMPLEMENTED();
-}
-
-bool Display::IsGpuChannelLost() {
-  NOTIMPLEMENTED();
-  return false;
-}
-
-void Display::EnsureWorkVisible() {
-  // This is only relevant for out-of-process command buffers.
-}
-
-gpu::CommandBufferNamespace Display::GetNamespaceID() const {
-  return gpu::CommandBufferNamespace::IN_PROCESS;
-}
-
-gpu::CommandBufferId Display::GetCommandBufferID() const {
-  return gpu::CommandBufferId();
-}
-
-int32_t Display::GetExtraCommandBufferData() const {
-  return 0;
+  base::AutoLock auto_lock(lock_);
+  if (!is_initialized_)
+    return ts->ReturnError(EGL_NOT_INITIALIZED, EGL_NO_CONTEXT);
+  if (share_ctx != EGL_NO_CONTEXT) {
+    egl::Context* share_context = GetContext(share_ctx);
+    if (!share_context)
+      return ts->ReturnError(EGL_BAD_CONTEXT, EGL_NO_CONTEXT);
+    // TODO(alokp): Add support for shared contexts.
+    return ts->ReturnError(EGL_BAD_MATCH, EGL_NO_CONTEXT);
+  }
+  if (!egl::Context::ValidateAttributeList(attrib_list))
+    return ts->ReturnError(EGL_BAD_ATTRIBUTE, EGL_NO_CONTEXT);
+  const egl::Config* config = GetConfig(cfg);
+  if (!config)
+    return ts->ReturnError(EGL_BAD_CONFIG, EGL_NO_CONTEXT);
+  scoped_refptr<Context> context(new Context(this, config));
+  if (!context)
+    return ts->ReturnError(EGL_BAD_ALLOC, EGL_NO_CONTEXT);
+  contexts_.emplace_back(context.get());
+  return ts->ReturnSuccess<EGLContext>(context.get());
+}
+
+EGLBoolean Display::DestroyContext(ThreadState* ts, EGLContext ctx) {
+  base::AutoLock auto_lock(lock_);
+  if (!is_initialized_)
+    return ts->ReturnError(EGL_NOT_INITIALIZED, EGL_FALSE);
+  auto it = std::find(contexts_.begin(), contexts_.end(), ctx);
+  if (it == contexts_.end())
+    return ts->ReturnError(EGL_BAD_CONTEXT, EGL_FALSE);
+  (*it)->MarkDestroyed();
+  contexts_.erase(it);
+  return ts->ReturnSuccess(EGL_TRUE);
 }
 
 uint64_t Display::GenerateFenceSyncRelease() {
+  base::AutoLock auto_lock(lock_);
   return next_fence_sync_release_++;
 }
 
 bool Display::IsFenceSyncRelease(uint64_t release) {
+  base::AutoLock auto_lock(lock_);
   return release > 0 && release < next_fence_sync_release_;
 }
 
 bool Display::IsFenceSyncFlushed(uint64_t release) {
   return IsFenceSyncRelease(release);
 }
 
 bool Display::IsFenceSyncFlushReceived(uint64_t release) {
   return IsFenceSyncRelease(release);
 }
 
-void Display::SignalSyncToken(const gpu::SyncToken& sync_token,
-                              const base::Closure& callback) {
-  NOTIMPLEMENTED();
+void Display::InitializeConfigsIfNeeded() {
+  lock_.AssertAcquired();
+  if (!configs_[0]) {
+    // The interface offers separate configs for window and pbuffer.
+    // This way we can record the client intention at context creation time.
+    // The GL implementation (gfx::GLContext and gfx::GLSurface) needs this
+    // distinction when creating a context.
+    configs_[0].reset(new Config(EGL_WINDOW_BIT));
+    configs_[1].reset(new Config(EGL_PBUFFER_BIT));
+  }
 }
 
-bool Display::CanWaitUnverifiedSyncToken(const gpu::SyncToken* sync_token) {
-  return false;
+const Config* Display::GetConfig(EGLConfig cfg) {
+  lock_.AssertAcquired();
+  for (const auto& config : configs_) {
+    if (config.get() == cfg)
+      return config.get();
+  }
+  return nullptr;
+}
+
+Surface* Display::GetSurface(EGLSurface surface) {
+  lock_.AssertAcquired();
+  auto it = std::find(surfaces_.begin(), surfaces_.end(), surface);
+  if (it == surfaces_.end())
+    return nullptr;
+  return it->get();
+}
+
+Context* Display::GetContext(EGLContext context) {
+  lock_.AssertAcquired();
+  auto it = std::find(contexts_.begin(), contexts_.end(), context);
+  if (it == contexts_.end())
+    return nullptr;
+  return it->get();
 }
 
 }  // namespace egl