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/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* 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 <pthread.h>
#include <string.h>
#include <stdlib.h>
#include <time.h>
#include <unistd.h>
#include <android/log.h>
#include <sys/syscall.h>
#include "mozilla/Alignment.h"
#include <vector>
#define NS_EXPORT __attribute__ ((visibility("default")))
#if ANDROID_VERSION < 17 || defined(MOZ_WIDGET_ANDROID)
/* Android doesn't have pthread_atfork(), so we need to use our own. */
struct AtForkFuncs {
void (*prepare)(void);
void (*parent)(void);
void (*child)(void);
};
/* jemalloc's initialization calls pthread_atfork. When pthread_atfork (see
* further below) stores the corresponding data, it's going to allocate memory,
* which will loop back to jemalloc's initialization, leading to a dead-lock.
* So, for that specific vector, we use a special allocator that returns a
* static buffer for small sizes, and force the initial vector capacity to
* a size enough to store one atfork function table. */
template <typename T>
struct SpecialAllocator: public std::allocator<T>
{
SpecialAllocator(): bufUsed(false) {}
inline typename std::allocator<T>::pointer allocate(typename std::allocator<T>::size_type n, const void * = 0) {
if (!bufUsed && n == 1) {
bufUsed = true;
return buf.addr();
}
return reinterpret_cast<T *>(::operator new(sizeof(T) * n));
}
inline void deallocate(typename std::allocator<T>::pointer p, typename std::allocator<T>::size_type n) {
if (p == buf.addr())
bufUsed = false;
else
::operator delete(p);
}
template<typename U>
struct rebind {
typedef SpecialAllocator<U> other;
};
private:
mozilla::AlignedStorage2<T> buf;
bool bufUsed;
};
static std::vector<AtForkFuncs, SpecialAllocator<AtForkFuncs> > atfork;
#endif
#define cpuacct_add(x)
#if ANDROID_VERSION < 17 || defined(MOZ_WIDGET_ANDROID)
extern "C" NS_EXPORT int
pthread_atfork(void (*prepare)(void), void (*parent)(void), void (*child)(void))
{
AtForkFuncs funcs;
funcs.prepare = prepare;
funcs.parent = parent;
funcs.child = child;
if (!atfork.capacity())
atfork.reserve(1);
atfork.push_back(funcs);
return 0;
}
extern "C" NS_EXPORT pid_t __fork(void);
extern "C" NS_EXPORT pid_t
fork(void)
{
pid_t pid;
for (auto it = atfork.rbegin();
it < atfork.rend(); ++it)
if (it->prepare)
it->prepare();
switch ((pid = syscall(__NR_clone, SIGCHLD, NULL, NULL, NULL, NULL))) {
case 0:
cpuacct_add(getuid());
for (auto it = atfork.begin();
it < atfork.end(); ++it)
if (it->child)
it->child();
break;
default:
for (auto it = atfork.begin();
it < atfork.end(); ++it)
if (it->parent)
it->parent();
}
return pid;
}
#endif
extern "C" NS_EXPORT int
raise(int sig)
{
// Bug 741272: Bionic incorrectly uses kill(), which signals the
// process, and thus could signal another thread (and let this one
// return "successfully" from raising a fatal signal).
//
// Bug 943170: POSIX specifies pthread_kill(pthread_self(), sig) as
// equivalent to raise(sig), but Bionic also has a bug with these
// functions, where a forked child will kill its parent instead.
extern pid_t gettid(void);
return syscall(__NR_tgkill, getpid(), gettid(), sig);
}
/* Flash plugin uses symbols that are not present in Android >= 4.4 */
namespace android {
namespace VectorImpl {
NS_EXPORT void reservedVectorImpl1(void) { }
NS_EXPORT void reservedVectorImpl2(void) { }
NS_EXPORT void reservedVectorImpl3(void) { }
NS_EXPORT void reservedVectorImpl4(void) { }
NS_EXPORT void reservedVectorImpl5(void) { }
NS_EXPORT void reservedVectorImpl6(void) { }
NS_EXPORT void reservedVectorImpl7(void) { }
NS_EXPORT void reservedVectorImpl8(void) { }
}
}
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