// Copyright 2017 the V8 project authors. All rights reserved.

// Use of this source code is governed by a BSD-style license that can be

// found in the LICENSE file.

// PLEASE READ BEFORE CHANGING THIS FILE!

//

// This file contains code that is used both inside and outside the out of

// bounds trap handler. Because this code runs in a trap handler context,

// use extra care when modifying this file. Here are some rules to follow.

//

// 1. Do not introduce any new external dependencies. This file needs

// to be self contained so it is easy to audit everything that a

// trap handler might do.

//

// 2. Any changes must be reviewed by someone from the crash reporting

// or security team. See OWNERS for suggested reviewers.

//

// For more information, see https://goo.gl/yMeyUY.

#include "src/trap-handler/trap-handler-internal.h"

namespace v8 {

namespace internal {

namespace trap_handler {

// We declare this as int rather than bool as a workaround for a glibc bug, in

// which the dynamic loader cannot handle executables whose TLS area is only

// 1 byte in size; see https://sourceware.org/bugzilla/show_bug.cgi?id=14898.

thread_local int g_thread_in_wasm_code;

static_assert(sizeof(g_thread_in_wasm_code) > 1,

"sizeof(thread_local_var) must be > 1, see "

"https://sourceware.org/bugzilla/show_bug.cgi?id=14898");

size_t gNumCodeObjects = 0;

CodeProtectionInfoListEntry* gCodeObjects = nullptr;

uintptr_t gV8SandboxBase = 0;

size_t gV8SandboxSize = 0;

std::atomic_size_t gRecoveredTrapCount = {0};

std::atomic<uintptr_t> gLandingPad = {0};

#if !defined(__cpp_lib_atomic_value_initialization) || \

__cpp_lib_atomic_value_initialization < 201911L

std::atomic_flag MetadataLock::spinlock_ = ATOMIC_FLAG_INIT;

#else

std::atomic_flag MetadataLock::spinlock_;

#endif

MetadataLock::MetadataLock() {

}

MetadataLock::~MetadataLock() {

if (g_thread_in_wasm_code) {

abort();

}

spinlock_.clear(std::memory_order_release);

}

} // namespace trap_handler

} // namespace internal

} // namespace v8