platform_system_core/libbacktrace/BacktraceThread.h
Christopher Ferris aa63d9f980 Use real time signal for threads instead of SIGURG.
This guarantees that any application is not also using this signal
for some other purpose.

Change-Id: I7c9bbb0ec8bb4e13322ecda951bcd43c6bf6ee1a
2014-04-30 16:32:47 -07:00

99 lines
2.7 KiB
C++

/*
* 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.
*/
#ifndef _LIBBACKTRACE_BACKTRACE_THREAD_H
#define _LIBBACKTRACE_BACKTRACE_THREAD_H
#include <inttypes.h>
#include <signal.h>
#include <sys/types.h>
#include "BacktraceImpl.h"
enum state_e {
STATE_WAITING = 0,
STATE_DUMPING,
STATE_DONE,
STATE_CANCEL,
};
// The signal used to cause a thread to dump the stack.
#if defined(__GLIBC__)
// GLIBC reserves __SIGRTMIN signals, so use SIGRTMIN to avoid errors.
#define THREAD_SIGNAL SIGRTMIN
#else
#define THREAD_SIGNAL (__SIGRTMIN+1)
#endif
class BacktraceThreadInterface;
struct ThreadEntry {
ThreadEntry(
BacktraceThreadInterface* impl, pid_t pid, pid_t tid,
size_t num_ignore_frames);
~ThreadEntry();
bool Match(pid_t chk_pid, pid_t chk_tid) { return (chk_pid == pid && chk_tid == tid); }
static ThreadEntry* AddThreadToUnwind(
BacktraceThreadInterface* thread_intf, pid_t pid, pid_t tid,
size_t num_ignored_frames);
BacktraceThreadInterface* thread_intf;
pid_t pid;
pid_t tid;
ThreadEntry* next;
ThreadEntry* prev;
int32_t state;
int num_ignore_frames;
};
// Interface class that does not contain any local storage, only defines
// virtual functions to be defined by subclasses.
class BacktraceThreadInterface {
public:
virtual ~BacktraceThreadInterface() { }
virtual void ThreadUnwind(
siginfo_t* siginfo, void* sigcontext, size_t num_ignore_frames) = 0;
};
class BacktraceThread : public BacktraceCurrent {
public:
// impl and thread_intf should point to the same object, this allows
// the compiler to catch if an implementation does not properly
// subclass both.
BacktraceThread(
BacktraceImpl* impl, BacktraceThreadInterface* thread_intf, pid_t tid,
BacktraceMap* map);
virtual ~BacktraceThread();
virtual bool Unwind(size_t num_ignore_frames);
virtual void ThreadUnwind(
siginfo_t* siginfo, void* sigcontext, size_t num_ignore_frames) {
thread_intf_->ThreadUnwind(siginfo, sigcontext, num_ignore_frames);
}
private:
virtual bool TriggerUnwindOnThread(ThreadEntry* entry);
virtual void FinishUnwind();
BacktraceThreadInterface* thread_intf_;
};
#endif // _LIBBACKTRACE_BACKTRACE_THREAD_H