/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 4 -*-
 * vim: set ts=8 sts=4 et sw=4 tw=99:
 * This Source Code Form is subject to the terms of the Mozilla Public
 * License, v. 2.0. If a copy of the MPL was not distributed with this
 * file, You can obtain one at http://mozilla.org/MPL/2.0/. */

#ifndef jit_AsmJSSignalHandlers_h
#define jit_AsmJSSignalHandlers_h

struct JSRuntime;

#ifdef XP_MACOSX
# include <mach/mach.h>
# include "jslock.h"
#endif

namespace js {

// Returns whether signal handlers for asm.js and for JitRuntime access
// violations have been installed.
bool
EnsureAsmJSSignalHandlersInstalled(JSRuntime *rt);

// Force any currently-executing asm.js code to call
// js::HandleExecutionInterrupt.
extern void
RequestInterruptForAsmJSCode(JSRuntime *rt);

// On OSX we are forced to use the lower-level Mach exception mechanism instead
// of Unix signals. Mach exceptions are not handled on the victim's stack but
// rather require an extra thread. For simplicity, we create one such thread
// per JSRuntime (upon the first use of asm.js in the JSRuntime). This thread
// and related resources are owned by AsmJSMachExceptionHandler which is owned
// by JSRuntime.
#ifdef XP_MACOSX
class AsmJSMachExceptionHandler
{
    bool installed_;
    PRThread *thread_;
    mach_port_t port_;

    void uninstall();

  public:
    AsmJSMachExceptionHandler();
    ~AsmJSMachExceptionHandler() { uninstall(); }
    mach_port_t port() const { return port_; }
    bool installed() const { return installed_; }
    bool install(JSRuntime *rt);
};
#endif

} // namespace js

#endif // jit_AsmJSSignalHandlers_h