| /* |
| * Copyright (C) 2011 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 "Corkscrew" |
| //#define LOG_NDEBUG 0 |
| |
| #include "backtrace-arch.h" |
| #include "backtrace-helper.h" |
| #include "ptrace-arch.h" |
| #include <corkscrew/map_info.h> |
| #include <corkscrew/symbol_table.h> |
| #include <corkscrew/ptrace.h> |
| #include <corkscrew/demangle.h> |
| |
| #include <unistd.h> |
| #include <signal.h> |
| #include <pthread.h> |
| #include <unwind.h> |
| #include <sys/exec_elf.h> |
| #include <cutils/log.h> |
| |
| #if HAVE_DLADDR |
| #include <dlfcn.h> |
| #endif |
| |
| typedef struct { |
| backtrace_frame_t* backtrace; |
| size_t ignore_depth; |
| size_t max_depth; |
| size_t ignored_frames; |
| size_t returned_frames; |
| } backtrace_state_t; |
| |
| static _Unwind_Reason_Code unwind_backtrace_callback(struct _Unwind_Context* context, void* arg) { |
| backtrace_state_t* state = (backtrace_state_t*)arg; |
| uintptr_t pc = _Unwind_GetIP(context); |
| if (pc) { |
| // TODO: Get information about the stack layout from the _Unwind_Context. |
| // This will require a new architecture-specific function to query |
| // the appropriate registers. Current callers of unwind_backtrace |
| // don't need this information, so we won't bother collecting it just yet. |
| add_backtrace_entry(pc, state->backtrace, |
| state->ignore_depth, state->max_depth, |
| &state->ignored_frames, &state->returned_frames); |
| } |
| return state->returned_frames < state->max_depth ? _URC_NO_REASON : _URC_END_OF_STACK; |
| } |
| |
| ssize_t unwind_backtrace(backtrace_frame_t* backtrace, size_t ignore_depth, size_t max_depth) { |
| backtrace_state_t state; |
| state.backtrace = backtrace; |
| state.ignore_depth = ignore_depth; |
| state.max_depth = max_depth; |
| state.ignored_frames = 0; |
| state.returned_frames = 0; |
| |
| _Unwind_Reason_Code rc =_Unwind_Backtrace(unwind_backtrace_callback, &state); |
| if (state.returned_frames) { |
| return state.returned_frames; |
| } |
| return rc == _URC_END_OF_STACK ? 0 : -1; |
| } |
| |
| #ifdef CORKSCREW_HAVE_ARCH |
| static pthread_mutex_t g_unwind_signal_mutex = PTHREAD_MUTEX_INITIALIZER; |
| static volatile struct { |
| backtrace_frame_t* backtrace; |
| size_t ignore_depth; |
| size_t max_depth; |
| size_t returned_frames; |
| bool done; |
| } g_unwind_signal_state; |
| |
| static void unwind_backtrace_thread_signal_handler(int n, siginfo_t* siginfo, void* sigcontext) { |
| backtrace_frame_t* backtrace = g_unwind_signal_state.backtrace; |
| if (backtrace) { |
| g_unwind_signal_state.backtrace = NULL; |
| g_unwind_signal_state.returned_frames = unwind_backtrace_signal_arch( |
| siginfo, sigcontext, backtrace, |
| g_unwind_signal_state.ignore_depth, |
| g_unwind_signal_state.max_depth); |
| g_unwind_signal_state.done = true; |
| } |
| } |
| #endif |
| |
| ssize_t unwind_backtrace_thread(pid_t tid, backtrace_frame_t* backtrace, |
| size_t ignore_depth, size_t max_depth) { |
| #ifdef CORKSCREW_HAVE_ARCH |
| struct sigaction act; |
| struct sigaction oact; |
| memset(&act, 0, sizeof(act)); |
| act.sa_sigaction = unwind_backtrace_thread_signal_handler; |
| act.sa_flags = SA_RESTART | SA_SIGINFO; |
| sigemptyset(&act.sa_mask); |
| |
| pthread_mutex_lock(&g_unwind_signal_mutex); |
| |
| g_unwind_signal_state.backtrace = backtrace; |
| g_unwind_signal_state.ignore_depth = ignore_depth; |
| g_unwind_signal_state.max_depth = max_depth; |
| g_unwind_signal_state.returned_frames = 0; |
| g_unwind_signal_state.done = false; |
| |
| ssize_t frames = -1; |
| if (!sigaction(SIGURG, &act, &oact)) { |
| if (!kill(tid, SIGURG)) { |
| while (!g_unwind_signal_state.done) { |
| usleep(1000); |
| } |
| frames = g_unwind_signal_state.returned_frames; |
| } |
| sigaction(SIGURG, &oact, NULL); |
| } |
| |
| g_unwind_signal_state.backtrace = NULL; |
| |
| pthread_mutex_unlock(&g_unwind_signal_mutex); |
| return frames; |
| #else |
| return -1; |
| #endif |
| } |
| |
| ssize_t unwind_backtrace_ptrace(pid_t tid, const ptrace_context_t* context, |
| backtrace_frame_t* backtrace, size_t ignore_depth, size_t max_depth) { |
| #ifdef CORKSCREW_HAVE_ARCH |
| return unwind_backtrace_ptrace_arch(tid, context, backtrace, ignore_depth, max_depth); |
| #else |
| return -1; |
| #endif |
| } |
| |
| static void init_backtrace_symbol(backtrace_symbol_t* symbol, uintptr_t pc) { |
| symbol->relative_pc = pc; |
| symbol->map_info = NULL; |
| symbol->name = NULL; |
| symbol->demangled_name = NULL; |
| } |
| |
| void get_backtrace_symbols(const backtrace_frame_t* backtrace, size_t frames, |
| backtrace_symbol_t* backtrace_symbols) { |
| const map_info_t* milist = my_map_info_list(); |
| for (size_t i = 0; i < frames; i++) { |
| const backtrace_frame_t* frame = &backtrace[i]; |
| backtrace_symbol_t* symbol = &backtrace_symbols[i]; |
| init_backtrace_symbol(symbol, frame->absolute_pc); |
| |
| const map_info_t* mi = find_map_info(milist, frame->absolute_pc); |
| if (mi) { |
| symbol->relative_pc = frame->absolute_pc - mi->start; |
| symbol->map_info = mi; |
| #if HAVE_DLADDR |
| Dl_info info; |
| if (dladdr((const void*)frame->absolute_pc, &info) && info.dli_sname) { |
| symbol->name = info.dli_sname; |
| symbol->demangled_name = demangle_symbol_name(symbol->name); |
| } |
| #endif |
| } |
| } |
| } |
| |
| void get_backtrace_symbols_ptrace(const ptrace_context_t* context, |
| const backtrace_frame_t* backtrace, size_t frames, |
| backtrace_symbol_t* backtrace_symbols) { |
| for (size_t i = 0; i < frames; i++) { |
| const backtrace_frame_t* frame = &backtrace[i]; |
| backtrace_symbol_t* symbol = &backtrace_symbols[i]; |
| init_backtrace_symbol(symbol, frame->absolute_pc); |
| |
| const map_info_t* mi; |
| const symbol_t* s; |
| find_symbol_ptrace(context, frame->absolute_pc, &mi, &s); |
| if (mi) { |
| symbol->relative_pc = frame->absolute_pc - mi->start; |
| symbol->map_info = mi; |
| } |
| if (s) { |
| symbol->name = s->name; |
| symbol->demangled_name = demangle_symbol_name(symbol->name); |
| } |
| } |
| } |
| |
| void free_backtrace_symbols(backtrace_symbol_t* backtrace_symbols, size_t frames) { |
| for (size_t i = 0; i < frames; i++) { |
| backtrace_symbol_t* symbol = &backtrace_symbols[i]; |
| free(symbol->demangled_name); |
| init_backtrace_symbol(symbol, 0); |
| } |
| } |