diff options
Diffstat (limited to 'libbacktrace/Corkscrew.cpp')
| -rw-r--r-- | libbacktrace/Corkscrew.cpp | 251 |
1 files changed, 251 insertions, 0 deletions
diff --git a/libbacktrace/Corkscrew.cpp b/libbacktrace/Corkscrew.cpp new file mode 100644 index 0000000..efeee2e --- /dev/null +++ b/libbacktrace/Corkscrew.cpp @@ -0,0 +1,251 @@ +/* + * 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. + */ + +#define LOG_TAG "libbacktrace" + +#include <backtrace/Backtrace.h> + +#include <string.h> + +#include <backtrace-arch.h> +#include <corkscrew/backtrace.h> + +#ifndef __USE_GNU +#define __USE_GNU +#endif +#include <dlfcn.h> + +#include "Corkscrew.h" + +//------------------------------------------------------------------------- +// CorkscrewMap functions. +//------------------------------------------------------------------------- +CorkscrewMap::CorkscrewMap(pid_t pid) : BacktraceMap(pid), map_info_(NULL) { +} + +CorkscrewMap::~CorkscrewMap() { + if (map_info_) { + free_map_info_list(map_info_); + map_info_ = NULL; + } +} + +bool CorkscrewMap::Build() { + map_info_ = load_map_info_list(pid_); + + // Use the information in map_info_ to construct the BacktraceMap data + // rather than reparsing /proc/self/maps. + map_info_t* cur_map = map_info_; + while (cur_map) { + backtrace_map_t map; + map.start = cur_map->start; + map.end = cur_map->end; + map.flags = 0; + if (cur_map->is_readable) { + map.flags |= PROT_READ; + } + if (cur_map->is_writable) { + map.flags |= PROT_WRITE; + } + if (cur_map->is_executable) { + map.flags |= PROT_EXEC; + } + map.name = cur_map->name; + + // The maps are in descending order, but we want them in ascending order. + maps_.push_front(map); + + cur_map = cur_map->next; + } + return map_info_ != NULL; +} + +//------------------------------------------------------------------------- +// CorkscrewCommon functions. +//------------------------------------------------------------------------- +bool CorkscrewCommon::GenerateFrameData( + backtrace_frame_t* cork_frames, ssize_t num_frames) { + if (num_frames < 0) { + BACK_LOGW("libcorkscrew unwind failed."); + return false; + } + + std::vector<backtrace_frame_data_t>* frames = GetFrames(); + frames->resize(num_frames); + size_t i = 0; + for (std::vector<backtrace_frame_data_t>::iterator it = frames->begin(); + it != frames->end(); ++it, ++i) { + it->num = i; + it->pc = cork_frames[i].absolute_pc; + it->sp = cork_frames[i].stack_top; + it->stack_size = cork_frames[i].stack_size; + it->func_offset = 0; + + it->map = FindMap(it->pc); + it->func_name = GetFunctionName(it->pc, &it->func_offset); + } + return true; +} + +//------------------------------------------------------------------------- +// CorkscrewCurrent functions. +//------------------------------------------------------------------------- +CorkscrewCurrent::CorkscrewCurrent() { +} + +CorkscrewCurrent::~CorkscrewCurrent() { +} + +bool CorkscrewCurrent::Unwind(size_t num_ignore_frames) { + backtrace_frame_t frames[MAX_BACKTRACE_FRAMES]; + ssize_t num_frames = unwind_backtrace(frames, num_ignore_frames, MAX_BACKTRACE_FRAMES); + + return GenerateFrameData(frames, num_frames); +} + +std::string CorkscrewCurrent::GetFunctionNameRaw(uintptr_t pc, uintptr_t* offset) { + *offset = 0; + + Dl_info info; + const backtrace_map_t* map = FindMap(pc); + if (map) { + if (dladdr((const void*)pc, &info)) { + if (info.dli_sname) { + *offset = pc - map->start - (uintptr_t)info.dli_saddr + (uintptr_t)info.dli_fbase; + return info.dli_sname; + } + } else { + // dladdr(3) didn't find a symbol; maybe it's static? Look in the ELF file... + symbol_table_t* symbol_table = load_symbol_table(map->name.c_str()); + if (symbol_table) { + // First check if we can find the symbol using a relative pc. + std::string name; + const symbol_t* elf_symbol = find_symbol(symbol_table, pc - map->start); + if (elf_symbol) { + name = elf_symbol->name; + *offset = pc - map->start - elf_symbol->start; + } else if ((elf_symbol = find_symbol(symbol_table, pc)) != NULL) { + // Found the symbol using the absolute pc. + name = elf_symbol->name; + *offset = pc - elf_symbol->start; + } + free_symbol_table(symbol_table); + return name; + } + } + } + return ""; +} + +//------------------------------------------------------------------------- +// CorkscrewThread functions. +//------------------------------------------------------------------------- +CorkscrewThread::CorkscrewThread() { +} + +CorkscrewThread::~CorkscrewThread() { +} + +void CorkscrewThread::ThreadUnwind( + siginfo_t* siginfo, void* sigcontext, size_t num_ignore_frames) { + backtrace_frame_t cork_frames[MAX_BACKTRACE_FRAMES]; + CorkscrewMap* map = static_cast<CorkscrewMap*>(GetMap()); + ssize_t num_frames = unwind_backtrace_signal_arch( + siginfo, sigcontext, map->GetMapInfo(), cork_frames, + num_ignore_frames, MAX_BACKTRACE_FRAMES); + if (num_frames > 0) { + std::vector<backtrace_frame_data_t>* frames = GetFrames(); + frames->resize(num_frames); + size_t i = 0; + for (std::vector<backtrace_frame_data_t>::iterator it = frames->begin(); + it != frames->end(); ++it, ++i) { + it->num = i; + it->pc = cork_frames[i].absolute_pc; + it->sp = cork_frames[i].stack_top; + it->stack_size = cork_frames[i].stack_size; + it->map = NULL; + it->func_offset = 0; + } + } +} + +//------------------------------------------------------------------------- +// CorkscrewPtrace functions. +//------------------------------------------------------------------------- +CorkscrewPtrace::CorkscrewPtrace() : ptrace_context_(NULL) { +} + +CorkscrewPtrace::~CorkscrewPtrace() { + if (ptrace_context_) { + free_ptrace_context(ptrace_context_); + ptrace_context_ = NULL; + } +} + +bool CorkscrewPtrace::Unwind(size_t num_ignore_frames) { + ptrace_context_ = load_ptrace_context(Tid()); + + backtrace_frame_t frames[MAX_BACKTRACE_FRAMES]; + ssize_t num_frames = unwind_backtrace_ptrace( + Tid(), ptrace_context_, frames, num_ignore_frames, MAX_BACKTRACE_FRAMES); + + return GenerateFrameData(frames, num_frames); +} + +std::string CorkscrewPtrace::GetFunctionNameRaw(uintptr_t pc, uintptr_t* offset) { + // Get information about a different process. + const map_info_t* map_info; + const symbol_t* symbol; + find_symbol_ptrace(ptrace_context_, pc, &map_info, &symbol); + char* symbol_name = NULL; + if (symbol) { + if (map_info) { + *offset = pc - map_info->start - symbol->start; + } + symbol_name = symbol->name; + return symbol_name; + } + + return ""; +} + +//------------------------------------------------------------------------- +// C++ object creation functions. +//------------------------------------------------------------------------- +Backtrace* CreateCurrentObj(BacktraceMap* map) { + return new BacktraceCurrent(new CorkscrewCurrent(), map); +} + +Backtrace* CreatePtraceObj(pid_t pid, pid_t tid, BacktraceMap* map) { + return new BacktracePtrace(new CorkscrewPtrace(), pid, tid, map); +} + +Backtrace* CreateThreadObj(pid_t tid, BacktraceMap* map) { + CorkscrewThread* thread_obj = new CorkscrewThread(); + return new BacktraceThread(thread_obj, thread_obj, tid, map); +} + +//------------------------------------------------------------------------- +// BacktraceMap create function. +//------------------------------------------------------------------------- +BacktraceMap* BacktraceMap::Create(pid_t pid) { + BacktraceMap* map = new CorkscrewMap(pid); + if (!map->Build()) { + delete map; + return NULL; + } + return map; +} |