blob: 8ab0dfabb56d835802e49238e3a8660144619525 [file] [log] [blame]
* Copyright (C) 2014 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
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* See the License for the specific language governing permissions and
* limitations under the License.
#include <stdint.h>
#include <sys/types.h>
#ifdef _WIN32
// MINGW does not define these constants.
#define PROT_NONE 0
#define PROT_READ 0x1
#define PROT_WRITE 0x2
#define PROT_EXEC 0x4
#include <sys/mman.h>
#include <deque>
#include <string>
#include <vector>
// Special flag to indicate a map is in /dev/. However, a map in
// /dev/ashmem/... does not set this flag.
static constexpr int PROT_DEVICE_MAP = 0x8000;
struct backtrace_map_t {
uintptr_t start = 0;
uintptr_t end = 0;
uintptr_t offset = 0;
uintptr_t load_base = 0;
int flags = 0;
std::string name;
class BacktraceMap {
// If uncached is true, then parse the current process map as of the call.
// Passing a map created with uncached set to true to Backtrace::Create()
// is unsupported.
static BacktraceMap* Create(pid_t pid, bool uncached = false);
static BacktraceMap* Create(pid_t pid, const std::vector<backtrace_map_t>& maps);
virtual ~BacktraceMap();
// Fill in the map data structure for the given address.
virtual void FillIn(uintptr_t addr, backtrace_map_t* map);
// The flags returned are the same flags as used by the mmap call.
// The values are PROT_*.
int GetFlags(uintptr_t pc) {
backtrace_map_t map;
FillIn(pc, &map);
if (IsValid(map)) {
return map.flags;
return PROT_NONE;
bool IsReadable(uintptr_t pc) { return GetFlags(pc) & PROT_READ; }
bool IsWritable(uintptr_t pc) { return GetFlags(pc) & PROT_WRITE; }
bool IsExecutable(uintptr_t pc) { return GetFlags(pc) & PROT_EXEC; }
// In order to use the iterators on this object, a caller must
// call the LockIterator and UnlockIterator function to guarantee
// that the data does not change while it's being used.
virtual void LockIterator() {}
virtual void UnlockIterator() {}
typedef std::deque<backtrace_map_t>::iterator iterator;
iterator begin() { return maps_.begin(); }
iterator end() { return maps_.end(); }
typedef std::deque<backtrace_map_t>::const_iterator const_iterator;
const_iterator begin() const { return maps_.begin(); }
const_iterator end() const { return maps_.end(); }
virtual bool Build();
static inline bool IsValid(const backtrace_map_t& map) {
return map.end > 0;
static uintptr_t GetRelativePc(const backtrace_map_t& map, uintptr_t pc) {
if (IsValid(map)) {
return pc - map.start + map.load_base;
} else {
return pc;
BacktraceMap(pid_t pid);
virtual bool ParseLine(const char* line, backtrace_map_t* map);
std::deque<backtrace_map_t> maps_;
pid_t pid_;
class ScopedBacktraceMapIteratorLock {
explicit ScopedBacktraceMapIteratorLock(BacktraceMap* map) : map_(map) {
~ScopedBacktraceMapIteratorLock() {
BacktraceMap* map_;