| // Copyright 2014 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. |
| |
| #ifndef THIRD_PARTY_BLINK_RENDERER_PLATFORM_BINDINGS_SCRIPT_FORBIDDEN_SCOPE_H_ |
| #define THIRD_PARTY_BLINK_RENDERER_PLATFORM_BINDINGS_SCRIPT_FORBIDDEN_SCOPE_H_ |
| |
| #include "base/auto_reset.h" |
| #include "base/macros.h" |
| #include "third_party/blink/renderer/platform/platform_export.h" |
| #include "third_party/blink/renderer/platform/wtf/allocator.h" |
| #include "third_party/blink/renderer/platform/wtf/stack_util.h" |
| #include "third_party/blink/renderer/platform/wtf/wtf.h" |
| |
| namespace blink { |
| |
| // Scoped disabling of script execution. |
| class PLATFORM_EXPORT ScriptForbiddenScope final { |
| STACK_ALLOCATED(); |
| DISALLOW_COPY_AND_ASSIGN(ScriptForbiddenScope); |
| |
| public: |
| ScriptForbiddenScope() { Enter(); } |
| ~ScriptForbiddenScope() { Exit(); } |
| |
| class PLATFORM_EXPORT AllowUserAgentScript final { |
| STACK_ALLOCATED(); |
| DISALLOW_COPY_AND_ASSIGN(AllowUserAgentScript); |
| |
| public: |
| AllowUserAgentScript() : saved_counter_(&GetMutableCounter(), 0) {} |
| ~AllowUserAgentScript() { DCHECK(!IsScriptForbidden()); } |
| |
| private: |
| base::AutoReset<unsigned> saved_counter_; |
| }; |
| |
| static bool IsScriptForbidden() { |
| if (LIKELY(!WTF::MayNotBeMainThread())) |
| return g_main_thread_counter_ > 0; |
| return GetMutableCounter() > 0; |
| } |
| |
| // DO NOT USE THESE FUNCTIONS FROM OUTSIDE OF THIS CLASS. |
| static void Enter() { |
| if (LIKELY(!WTF::MayNotBeMainThread())) { |
| ++g_main_thread_counter_; |
| } else { |
| ++GetMutableCounter(); |
| } |
| } |
| static void Exit() { |
| DCHECK(IsScriptForbidden()); |
| if (LIKELY(!WTF::MayNotBeMainThread())) { |
| --g_main_thread_counter_; |
| } else { |
| --GetMutableCounter(); |
| } |
| } |
| |
| private: |
| static unsigned& GetMutableCounter(); |
| static unsigned g_main_thread_counter_; |
| }; |
| |
| } // namespace blink |
| |
| #endif // THIRD_PARTY_BLINK_RENDERER_PLATFORM_BINDINGS_SCRIPT_FORBIDDEN_SCOPE_H_ |