Allow textures to be moved from one GL context group to another.

gpu/command_buffer/service/mailbox_manager.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 "crypto/secure_hash.h"
+#include "crypto/symmetric_key.h"
+#include "gpu/command_buffer/service/gl_utils.h"
+#include "gpu/command_buffer/service/mailbox_manager.h"
+#include "gpu/command_buffer/service/texture_definition.h"
+
+namespace gpu {
+namespace gles2 {
+
+MailboxManager::MailboxManager() {
+  crypto::SymmetricKey* key =
+      crypto::SymmetricKey::GenerateRandomKey(crypto::SymmetricKey::AES,
+                                              sizeof(private_key_) * 8);
+  std::string raw_key;
+  key->GetRawKey(&raw_key);
+
+  DCHECK(raw_key.length() == sizeof(private_key_));
+
+  raw_key.copy(reinterpret_cast<char*>(private_key_), sizeof(private_key_));
+}
+
+MailboxManager::~MailboxManager() {
+}
+
+void MailboxManager::GenerateMailboxName(MailboxName* name) {
+  crypto::SymmetricKey* key =
+      crypto::SymmetricKey::GenerateRandomKey(crypto::SymmetricKey::AES,
+                                              sizeof(name->key) * 8);
+  std::string raw_key;
+  key->GetRawKey(&raw_key);
+
+  DCHECK(raw_key.length() == sizeof(name->key));
+
+  raw_key.copy(reinterpret_cast<char*>(name->key), sizeof(name->key));
+
+  SignMailboxName(name);
+}
+
+TextureDefinition* MailboxManager::ConsumeTexture(unsigned target,
+                                                  const MailboxName& name) {
+  if (!IsMailboxNameValid(name))
+    return NULL;
+
+  TextureDefinitionMap::iterator it =
+      textures_.find(TargetName(target, name));
+  if (it == textures_.end()) {
+    NOTREACHED();
+    return NULL;
+  }
+
+  TextureDefinition* definition = it->second.definition.release();
+  textures_.erase(it);
+
+  return definition;
+}
+
+bool MailboxManager::ProduceTexture(unsigned target,
+                                    const MailboxName& name,
+                                    TextureDefinition* definition,
+                                    TextureManager* owner) {
+  if (!IsMailboxNameValid(name))
+    return false;
+
+  TextureDefinitionMap::iterator it =
+      textures_.find(TargetName(target, name));
+  if (it != textures_.end()) {
+    NOTREACHED();
+    GLuint service_id = it->second.definition->ReleaseServiceId();
+    glDeleteTextures(1, &service_id);
+    it->second = OwnedTextureDefinition(definition, owner);
+  } else {
+    textures_.insert(std::make_pair(
+        TargetName(target, name),
+        OwnedTextureDefinition(definition, owner)));
+  }
+
+  return true;
+}
+
+void MailboxManager::DestroyOwnedTextures(TextureManager* owner,
+                                          bool have_context) {
+  TextureDefinitionMap::iterator it = textures_.begin();
+  while (it != textures_.end()) {
+    if (it->second.owner == owner) {
+      NOTREACHED();
+      GLuint service_id = it->second.definition->ReleaseServiceId();
+      if (have_context)
+        glDeleteTextures(1, &service_id);
+      it = textures_.erase(it);
+    } else {
+      ++it;
+    }
+  }
+}
+
+void MailboxManager::SignMailboxName(MailboxName* name) {
+  scoped_ptr<crypto::SecureHash> hash(crypto::SecureHash::Create(
+      crypto::SecureHash::SHA256));
+
+  hash->Update(name->key, sizeof(name->key));
+  hash->Update(private_key_, sizeof(private_key_));
+  hash->Finish(name->signature, sizeof(name->signature));
+}
+
+bool MailboxManager::IsMailboxNameValid(const MailboxName& name) {
+  MailboxName signed_name = name;
+  SignMailboxName(&signed_name);
+
+  return memcmp(name.signature,
+                signed_name.signature,
+                sizeof(name.signature)) == 0;
+}
+
+MailboxManager::TargetName::TargetName(unsigned target, const MailboxName& name)
+    : target(target),
+      name(name) {
+}
+
+size_t MailboxManager::TargetNameCompare::operator() (
+    const TargetName& value) const {
+  size_t hash = value.target;
+  for (int i = 0; i < arraysize(value.name.key); ++i)
+    hash ^= value.name.key[i];
+  return hash;
+}
+
+int MailboxManager::TargetNameCompare::operator() (
+    const TargetName& lhs,
+    const TargetName& rhs) const {
+  return memcmp(&lhs, &rhs, sizeof(lhs));
+}
+
+MailboxManager::OwnedTextureDefinition::OwnedTextureDefinition(
+    TextureDefinition* definition,
+    TextureManager* owner)
+    : definition(definition),
+      owner(owner) {
+}
+
+MailboxManager::OwnedTextureDefinition::~OwnedTextureDefinition() {
+}
+}  // namespace gles2
+}  // namespace gpu