| /* |
| * 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 <sys/types.h> |
| |
| #include <backtrace/Backtrace.h> |
| #include <backtrace/BacktraceMap.h> |
| |
| #define UNW_LOCAL_ONLY |
| #include <libunwind.h> |
| |
| #include "UnwindCurrent.h" |
| #include "UnwindMap.h" |
| |
| // Define the ucontext_t structures needed for each supported arch. |
| #if defined(__arm__) |
| // The current version of the <signal.h> doesn't define ucontext_t. |
| #include <asm/sigcontext.h> // Ensure 'struct sigcontext' is defined. |
| |
| // Machine context at the time a signal was raised. |
| typedef struct ucontext { |
| uint32_t uc_flags; |
| struct ucontext* uc_link; |
| stack_t uc_stack; |
| struct sigcontext uc_mcontext; |
| uint32_t uc_sigmask; |
| } ucontext_t; |
| #elif defined(__i386__) |
| #include <asm/sigcontext.h> |
| #include <asm/ucontext.h> |
| typedef struct ucontext ucontext_t; |
| #elif !defined(__mips__) && !defined(__aarch64__) |
| #error Unsupported architecture. |
| #endif |
| |
| //------------------------------------------------------------------------- |
| // UnwindCurrent functions. |
| //------------------------------------------------------------------------- |
| UnwindCurrent::UnwindCurrent() { |
| } |
| |
| UnwindCurrent::~UnwindCurrent() { |
| } |
| |
| bool UnwindCurrent::Unwind(size_t num_ignore_frames) { |
| int ret = unw_getcontext(&context_); |
| if (ret < 0) { |
| BACK_LOGW("unw_getcontext failed %d", ret); |
| return false; |
| } |
| return UnwindFromContext(num_ignore_frames, true); |
| } |
| |
| std::string UnwindCurrent::GetFunctionNameRaw(uintptr_t pc, uintptr_t* offset) { |
| *offset = 0; |
| char buf[512]; |
| unw_word_t value; |
| if (unw_get_proc_name_by_ip(unw_local_addr_space, pc, buf, sizeof(buf), |
| &value, &context_) >= 0 && buf[0] != '\0') { |
| *offset = static_cast<uintptr_t>(value); |
| return buf; |
| } |
| return ""; |
| } |
| |
| bool UnwindCurrent::UnwindFromContext(size_t num_ignore_frames, bool resolve) { |
| // The cursor structure is pretty large, do not put it on the stack. |
| unw_cursor_t* cursor = new unw_cursor_t; |
| int ret = unw_init_local(cursor, &context_); |
| if (ret < 0) { |
| BACK_LOGW("unw_init_local failed %d", ret); |
| delete cursor; |
| return false; |
| } |
| |
| std::vector<backtrace_frame_data_t>* frames = GetFrames(); |
| frames->reserve(MAX_BACKTRACE_FRAMES); |
| size_t num_frames = 0; |
| do { |
| unw_word_t pc; |
| ret = unw_get_reg(cursor, UNW_REG_IP, &pc); |
| if (ret < 0) { |
| BACK_LOGW("Failed to read IP %d", ret); |
| break; |
| } |
| unw_word_t sp; |
| ret = unw_get_reg(cursor, UNW_REG_SP, &sp); |
| if (ret < 0) { |
| BACK_LOGW("Failed to read SP %d", ret); |
| break; |
| } |
| |
| if (num_ignore_frames == 0) { |
| frames->resize(num_frames+1); |
| backtrace_frame_data_t* frame = &frames->at(num_frames); |
| frame->num = num_frames; |
| frame->pc = static_cast<uintptr_t>(pc); |
| frame->sp = static_cast<uintptr_t>(sp); |
| frame->stack_size = 0; |
| |
| if (num_frames > 0) { |
| // Set the stack size for the previous frame. |
| backtrace_frame_data_t* prev = &frames->at(num_frames-1); |
| prev->stack_size = frame->sp - prev->sp; |
| } |
| |
| if (resolve) { |
| frame->func_name = GetFunctionName(frame->pc, &frame->func_offset); |
| frame->map = FindMap(frame->pc); |
| } else { |
| frame->map = NULL; |
| frame->func_offset = 0; |
| } |
| num_frames++; |
| } else { |
| num_ignore_frames--; |
| } |
| ret = unw_step (cursor); |
| } while (ret > 0 && num_frames < MAX_BACKTRACE_FRAMES); |
| |
| delete cursor; |
| return true; |
| } |
| |
| void UnwindCurrent::ExtractContext(void* sigcontext) { |
| unw_tdep_context_t* context = reinterpret_cast<unw_tdep_context_t*>(&context_); |
| const ucontext_t* uc = reinterpret_cast<const ucontext_t*>(sigcontext); |
| |
| #if defined(__arm__) |
| context->regs[0] = uc->uc_mcontext.arm_r0; |
| context->regs[1] = uc->uc_mcontext.arm_r1; |
| context->regs[2] = uc->uc_mcontext.arm_r2; |
| context->regs[3] = uc->uc_mcontext.arm_r3; |
| context->regs[4] = uc->uc_mcontext.arm_r4; |
| context->regs[5] = uc->uc_mcontext.arm_r5; |
| context->regs[6] = uc->uc_mcontext.arm_r6; |
| context->regs[7] = uc->uc_mcontext.arm_r7; |
| context->regs[8] = uc->uc_mcontext.arm_r8; |
| context->regs[9] = uc->uc_mcontext.arm_r9; |
| context->regs[10] = uc->uc_mcontext.arm_r10; |
| context->regs[11] = uc->uc_mcontext.arm_fp; |
| context->regs[12] = uc->uc_mcontext.arm_ip; |
| context->regs[13] = uc->uc_mcontext.arm_sp; |
| context->regs[14] = uc->uc_mcontext.arm_lr; |
| context->regs[15] = uc->uc_mcontext.arm_pc; |
| #elif defined(__mips__) || defined(__i386__) |
| context->uc_mcontext = uc->uc_mcontext; |
| #endif |
| } |
| |
| //------------------------------------------------------------------------- |
| // UnwindThread functions. |
| //------------------------------------------------------------------------- |
| UnwindThread::UnwindThread() { |
| } |
| |
| UnwindThread::~UnwindThread() { |
| } |
| |
| void UnwindThread::ThreadUnwind( |
| siginfo_t* /*siginfo*/, void* sigcontext, size_t num_ignore_frames) { |
| ExtractContext(sigcontext); |
| UnwindFromContext(num_ignore_frames, false); |
| } |
| |
| //------------------------------------------------------------------------- |
| // C++ object creation function. |
| //------------------------------------------------------------------------- |
| Backtrace* CreateCurrentObj(BacktraceMap* map) { |
| return new BacktraceCurrent(new UnwindCurrent(), map); |
| } |
| |
| Backtrace* CreateThreadObj(pid_t tid, BacktraceMap* map) { |
| UnwindThread* thread_obj = new UnwindThread(); |
| return new BacktraceThread(thread_obj, thread_obj, tid, map); |
| } |