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Diffstat (limited to 'mozglue/build/BionicGlue.cpp')
-rw-r--r-- | mozglue/build/BionicGlue.cpp | 157 |
1 files changed, 157 insertions, 0 deletions
diff --git a/mozglue/build/BionicGlue.cpp b/mozglue/build/BionicGlue.cpp new file mode 100644 index 000000000..208fcce68 --- /dev/null +++ b/mozglue/build/BionicGlue.cpp @@ -0,0 +1,157 @@ +/* -*- 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 + +#ifdef MOZ_WIDGET_GONK +#include "cpuacct.h" + +#if ANDROID_VERSION < 17 || defined(MOZ_WIDGET_ANDROID) +extern "C" NS_EXPORT int +timer_create(clockid_t, struct sigevent*, timer_t*) +{ + __android_log_print(ANDROID_LOG_ERROR, "BionicGlue", "timer_create not supported!"); + abort(); + return -1; +} +#endif + +#else +#define cpuacct_add(x) +#endif + +#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 */ +#ifndef MOZ_WIDGET_GONK +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) { } + } +} +#endif + |