Merge "Refactor the code."

  uintptr_t func_offset;  // pc relative to the start of the function, only valid if func_name is not NULL.

};

// Forward declarations.

class BacktraceImpl;

#if defined(__APPLE__)

struct __darwin_ucontext;

typedef __darwin_ucontext ucontext_t;

  virtual ~Backtrace();

  // Get the current stack trace and store in the backtrace_ structure.

  virtual bool Unwind(size_t num_ignore_frames, ucontext_t* context = NULL);

  virtual bool Unwind(size_t num_ignore_frames, ucontext_t* context = NULL) = 0;

  // Get the function name and offset into the function given the pc.

  // If the string is empty, then no valid function name was found.

  virtual std::string FormatFrameData(size_t frame_num);

  virtual std::string FormatFrameData(const backtrace_frame_data_t* frame);

  pid_t Pid() { return pid_; }

  pid_t Tid() { return tid_; }

  size_t NumFrames() { return frames_.size(); }

  pid_t Pid() const { return pid_; }

  pid_t Tid() const { return tid_; }

  size_t NumFrames() const { return frames_.size(); }

  const backtrace_frame_data_t* GetFrame(size_t frame_num) {

    if (frame_num >= frames_.size()) {

  BacktraceMap* GetMap() { return map_; }

protected:

  Backtrace(BacktraceImpl* impl, pid_t pid, BacktraceMap* map);

  Backtrace(pid_t pid, pid_t tid, BacktraceMap* map);

  // The name returned is not demangled, GetFunctionName() takes care of

  // demangling the name.

  virtual std::string GetFunctionNameRaw(uintptr_t pc, uintptr_t* offset) = 0;

  virtual bool VerifyReadWordArgs(uintptr_t ptr, word_t* out_value);

  bool map_shared_;

  std::vector<backtrace_frame_data_t> frames_;

  BacktraceImpl* impl_;

  friend class BacktraceImpl;

};

#endif // _BACKTRACE_BACKTRACE_H

LOCAL_MODULE := $(module)

LOCAL_MODULE_TAGS := $(module_tag)

LOCAL_MULTILIB := $($(module)_multilib)

ifeq ($(LOCAL_MULTILIB),both)

ifneq ($(build_target),$(filter $(build_target),SHARED_LIBRARY STATIC_LIBRRARY))

  LOCAL_MODULE_STEM_32 := $(LOCAL_MODULE)32

  LOCAL_MODULE_STEM_64 := $(LOCAL_MODULE)64

endif

endif

LOCAL_ADDITIONAL_DEPENDENCIES := \

    $(LOCAL_PATH)/Android.mk \

    $(LOCAL_PATH)/Android.build.mk \

LOCAL_CFLAGS := \

    $(common_cflags) \

    $(libbacktrace_common_cflags) \

    $($(module)_cflags) \

    $($(module)_cflags_$(build_type)) \

    $(libbacktrace_common_clang_cflags) \

LOCAL_CONLYFLAGS += \

    $(common_conlyflags) \

    $(libbacktrace_common_conlyflags) \

    $($(module)_conlyflags) \

    $($(module)_conlyflags_$(build_type)) \

LOCAL_CPPFLAGS += \

    $(common_cppflags) \

    $(libbacktrace_common_cppflags) \

    $($(module)_cppflags) \

    $($(module)_cppflags_$(build_type)) \

LOCAL_C_INCLUDES := \

    $(common_c_includes) \

    $(libbacktrace_common_c_includes) \

    $($(module)_c_includes) \

    $($(module)_c_includes_$(build_type)) \

LOCAL_PATH:= $(call my-dir)

common_cflags := \

libbacktrace_common_cflags := \

	-Wall \

	-Werror \

common_conlyflags := \

libbacktrace_common_conlyflags := \

	-std=gnu99 \

common_cppflags := \

libbacktrace_common_cppflags := \

	-std=gnu++11 \

# The latest clang (r230699) does not allow SP/PC to be declared in inline asm lists.

# The libbacktrace library.

#-------------------------------------------------------------------------

libbacktrace_src_files := \

	BacktraceImpl.cpp \

	Backtrace.cpp \

	BacktraceCurrent.cpp \

	BacktraceMap.cpp \

	BacktraceThread.cpp \

	BacktracePtrace.cpp \

	thread_utils.c \

libbacktrace_shared_libraries_target := \

	libcutils \

libbacktrace_src_files += \

	ThreadEntry.cpp \

	UnwindCurrent.cpp \

	UnwindMap.cpp \

	UnwindPtrace.cpp \

libbacktrace_shared_libraries_target := \

	libcutils \

libbacktrace_shared_libraries := \

	libbase \

	libunwind \

	libunwind-ptrace \

module_tag := debug

build_type := target

build_target := SHARED_LIBRARY

libbacktrace_test_multilib := both

include $(LOCAL_PATH)/Android.build.mk

build_type := host

include $(LOCAL_PATH)/Android.build.mk

module_tag := debug

build_type := target

build_target := NATIVE_TEST

backtrace_test_multilib := both

include $(LOCAL_PATH)/Android.build.mk

build_type := host

include $(LOCAL_PATH)/Android.build.mk

/*

 * Copyright (C) 2013 The Android Open Source Project

 *

 * Licensed under the Apache License, Version 2.0 (the "License");

 * you may not use this file except in compliance with the License.

 * You may obtain a copy of the License at

 *

 *      http://www.apache.org/licenses/LICENSE-2.0

 *

 * Unless required by applicable law or agreed to in writing, software

 * distributed under the License is distributed on an "AS IS" BASIS,

 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.

 * See the License for the specific language governing permissions and

 * limitations under the License.

 */

#include <inttypes.h>

#include <stdint.h>

#include <stdlib.h>

#include <sys/types.h>

#include <ucontext.h>

#include <string>

#include <base/stringprintf.h>

#include <backtrace/Backtrace.h>

#include <backtrace/BacktraceMap.h>

#include "BacktraceLog.h"

#include "thread_utils.h"

#include "UnwindCurrent.h"

#include "UnwindPtrace.h"

using android::base::StringPrintf;

//-------------------------------------------------------------------------

// Backtrace functions.

//-------------------------------------------------------------------------

Backtrace::Backtrace(pid_t pid, pid_t tid, BacktraceMap* map)

    : pid_(pid), tid_(tid), map_(map), map_shared_(true) {

  if (map_ == nullptr) {

    map_ = BacktraceMap::Create(pid);

    map_shared_ = false;

  }

}

Backtrace::~Backtrace() {

  if (map_ && !map_shared_) {

    delete map_;

    map_ = nullptr;

  }

}

extern "C" char* __cxa_demangle(const char* mangled, char* buf, size_t* len,

                                int* status);

std::string Backtrace::GetFunctionName(uintptr_t pc, uintptr_t* offset) {

  std::string func_name = GetFunctionNameRaw(pc, offset);

  if (!func_name.empty()) {

#if defined(__APPLE__)

    // Mac OS' __cxa_demangle demangles "f" as "float"; last tested on 10.7.

    if (func_name[0] != '_') {

      return func_name;

    }

#endif

    char* name = __cxa_demangle(func_name.c_str(), 0, 0, 0);

    if (name) {

      func_name = name;

      free(name);

    }

  }

  return func_name;

}

bool Backtrace::VerifyReadWordArgs(uintptr_t ptr, word_t* out_value) {

  if (ptr & (sizeof(word_t)-1)) {

    BACK_LOGW("invalid pointer %p", reinterpret_cast<void*>(ptr));

    *out_value = static_cast<word_t>(-1);

    return false;

  }

  return true;

}

std::string Backtrace::FormatFrameData(size_t frame_num) {

  if (frame_num >= frames_.size()) {

    return "";

  }

  return FormatFrameData(&frames_[frame_num]);

}

std::string Backtrace::FormatFrameData(const backtrace_frame_data_t* frame) {

  const char* map_name;

  if (BacktraceMap::IsValid(frame->map) && !frame->map.name.empty()) {

    map_name = frame->map.name.c_str();

  } else {

    map_name = "<unknown>";

  }

  uintptr_t relative_pc;

  if (BacktraceMap::IsValid(frame->map)) {

    relative_pc = frame->pc - frame->map.start;

  } else {

    relative_pc = frame->pc;

  }

  std::string line(StringPrintf("#%02zu pc %" PRIPTR "  %s", frame->num, relative_pc, map_name));

  if (!frame->func_name.empty()) {

    line += " (" + frame->func_name;

    if (frame->func_offset) {

      line += StringPrintf("+%" PRIuPTR, frame->func_offset);

    }

    line += ')';

  }

  return line;

}

void Backtrace::FillInMap(uintptr_t pc, backtrace_map_t* map) {

  map_->FillIn(pc, map);

}

Backtrace* Backtrace::Create(pid_t pid, pid_t tid, BacktraceMap* map) {

  if (pid == BACKTRACE_CURRENT_PROCESS) {

    pid = getpid();

    if (tid == BACKTRACE_CURRENT_THREAD) {

      tid = gettid();

    }

  } else if (tid == BACKTRACE_CURRENT_THREAD) {

    tid = pid;

  }

  if (pid == getpid()) {

    return new UnwindCurrent(pid, tid, map);

  } else {

    return new UnwindPtrace(pid, tid, map);

  }

}

/*

 * Copyright (C) 2013 The Android Open Source Project

 *

 * Licensed under the Apache License, Version 2.0 (the "License");

 * you may not use this file except in compliance with the License.

 * You may obtain a copy of the License at

 *

 *      http://www.apache.org/licenses/LICENSE-2.0

 *

 * Unless required by applicable law or agreed to in writing, software

 * distributed under the License is distributed on an "AS IS" BASIS,

 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.

 * See the License for the specific language governing permissions and

 * limitations under the License.

 */

#include <errno.h>

#include <stdint.h>

#include <string.h>

#include <sys/param.h>

#include <sys/ptrace.h>

#include <sys/types.h>

#include <ucontext.h>

#include <unistd.h>

#include <string>

#include <backtrace/Backtrace.h>

#include <backtrace/BacktraceMap.h>

#include "BacktraceCurrent.h"

#include "BacktraceLog.h"

#include "ThreadEntry.h"

#include "thread_utils.h"

bool BacktraceCurrent::ReadWord(uintptr_t ptr, word_t* out_value) {

  if (!VerifyReadWordArgs(ptr, out_value)) {

    return false;

  }

  backtrace_map_t map;

  FillInMap(ptr, &map);

  if (BacktraceMap::IsValid(map) && map.flags & PROT_READ) {

    *out_value = *reinterpret_cast<word_t*>(ptr);

    return true;

  } else {

    BACK_LOGW("pointer %p not in a readable map", reinterpret_cast<void*>(ptr));

    *out_value = static_cast<word_t>(-1);

    return false;

  }

}

size_t BacktraceCurrent::Read(uintptr_t addr, uint8_t* buffer, size_t bytes) {

  backtrace_map_t map;

  FillInMap(addr, &map);

  if (!BacktraceMap::IsValid(map) || !(map.flags & PROT_READ)) {

    return 0;

  }

  bytes = MIN(map.end - addr, bytes);

  memcpy(buffer, reinterpret_cast<uint8_t*>(addr), bytes);

  return bytes;

}

bool BacktraceCurrent::Unwind(size_t num_ignore_frames, ucontext_t* ucontext) {

  if (ucontext) {

    return UnwindFromContext(num_ignore_frames, ucontext);

  }

  if (Tid() != gettid()) {

    return UnwindThread(num_ignore_frames);

  }

  return UnwindFromContext(num_ignore_frames, nullptr);

}

static pthread_mutex_t g_sigaction_mutex = PTHREAD_MUTEX_INITIALIZER;

static void SignalHandler(int, siginfo_t*, void* sigcontext) {

  ThreadEntry* entry = ThreadEntry::Get(getpid(), gettid(), false);

  if (!entry) {

    BACK_LOGW("Unable to find pid %d tid %d information", getpid(), gettid());

    return;

  }

  entry->CopyUcontextFromSigcontext(sigcontext);

  // Indicate the ucontext is now valid.

  entry->Wake();

  // Pause the thread until the unwind is complete. This avoids having

  // the thread run ahead causing problems.

  // The number indicates that we are waiting for the second Wake() call

  // overall which is made by the thread requesting an unwind.

  entry->Wait(2);

  ThreadEntry::Remove(entry);

}

bool BacktraceCurrent::UnwindThread(size_t num_ignore_frames) {

  // Prevent multiple threads trying to set the trigger action on different

  // threads at the same time.

  pthread_mutex_lock(&g_sigaction_mutex);

  ThreadEntry* entry = ThreadEntry::Get(Pid(), Tid());

  entry->Lock();

  struct sigaction act, oldact;

  memset(&act, 0, sizeof(act));

  act.sa_sigaction = SignalHandler;

  act.sa_flags = SA_RESTART | SA_SIGINFO | SA_ONSTACK;

  sigemptyset(&act.sa_mask);

  if (sigaction(THREAD_SIGNAL, &act, &oldact) != 0) {

    BACK_LOGW("sigaction failed %s", strerror(errno));

    entry->Unlock();

    ThreadEntry::Remove(entry);

    pthread_mutex_unlock(&g_sigaction_mutex);

    return false;

  }

  if (tgkill(Pid(), Tid(), THREAD_SIGNAL) != 0) {

    BACK_LOGW("tgkill %d failed: %s", Tid(), strerror(errno));

    sigaction(THREAD_SIGNAL, &oldact, nullptr);

    entry->Unlock();

    ThreadEntry::Remove(entry);

    pthread_mutex_unlock(&g_sigaction_mutex);

    return false;

  }

  // Wait for the thread to get the ucontext. The number indicates

  // that we are waiting for the first Wake() call made by the thread.

  entry->Wait(1);

  // After the thread has received the signal, allow other unwinders to

  // continue.

  sigaction(THREAD_SIGNAL, &oldact, nullptr);

  pthread_mutex_unlock(&g_sigaction_mutex);

  bool unwind_done = UnwindFromContext(num_ignore_frames, entry->GetUcontext());

  // Tell the signal handler to exit and release the entry.

  entry->Wake();

  return unwind_done;

}