/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*-

 * vim: sw=4 ts=4 et :

 */

/* 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/. */

#include "mozilla/mozalloc_abort.h"

#ifdef ANDROID

# include <android/log.h>

#endif

#ifdef MOZ_WIDGET_ANDROID

# include "APKOpen.h"

# include "dlfcn.h"

#endif

#include <stdio.h>

#include <string.h>

#include "mozilla/Assertions.h"

#include "mozilla/Sprintf.h"

void

mozalloc_abort(const char* const msg)

{

#ifndef ANDROID

    fputs(msg, stderr);

    fputs("\n", stderr);

#else

    __android_log_print(ANDROID_LOG_ERROR, "Gecko", "mozalloc_abort: %s", msg);

#endif

#ifdef MOZ_WIDGET_ANDROID

    abortThroughJava(msg);

#endif

    MOZ_CRASH();

}

#ifdef MOZ_WIDGET_ANDROID

template <size_t N>

void fillAbortMessage(char (&msg)[N], uintptr_t retAddress) {

    /*

     * On Android, we often don't have reliable backtrace when crashing inside

     * abort(). Therefore, we try to find out who is calling abort() and add

     * that to the message.

     */

    Dl_info info = {};

    dladdr(reinterpret_cast<void*>(retAddress), &info);

    const char* const module = info.dli_fname ? info.dli_fname : "";

    const char* const base_module = strrchr(module, '/');

    const void* const module_offset =

        reinterpret_cast<void*>(retAddress - uintptr_t(info.dli_fbase));

    const char* const sym = info.dli_sname ? info.dli_sname : "";

    SprintfLiteral(msg, "abort() called from %s:%p (%s)",

                   base_module ? base_module + 1 : module, module_offset, sym);

}

#endif

#if defined(XP_UNIX) && !defined(MOZ_ASAN)

// Define abort() here, so that it is used instead of the system abort(). This

// lets us control the behavior when aborting, in order to get better results

// on *NIX platforms. See mozalloc_abort for details.

//

// For AddressSanitizer, we must not redefine system abort because the ASan

// option "abort_on_error=1" calls abort() and therefore causes the following

// call chain with our redefined abort:

//

// ASan -> abort() -> moz_abort() -> MOZ_CRASH() -> Segmentation fault

//

// That segmentation fault will be interpreted as another bug by ASan and as a

// result, ASan will just exit(1) instead of aborting.

extern "C" void abort(void)

{

#ifdef MOZ_WIDGET_ANDROID

    char msg[64] = {};

    fillAbortMessage(msg, uintptr_t(__builtin_return_address(0)));

#else

    const char* const msg = "Redirecting call to abort() to mozalloc_abort\n";

#endif

    mozalloc_abort(msg);

    // We won't reach here because mozalloc_abort() is MOZ_NORETURN. But that

    // annotation isn't used on ARM (see mozalloc_abort.h for why) so we add a

    // redundant MOZ_CRASH() here to avoid a "'noreturn' function does return"

    // warning.

    MOZ_CRASH();

}

#endif