diff options
Diffstat (limited to 'libcorkscrew/backtrace.c')
| -rw-r--r-- | libcorkscrew/backtrace.c | 335 |
1 files changed, 0 insertions, 335 deletions
diff --git a/libcorkscrew/backtrace.c b/libcorkscrew/backtrace.c deleted file mode 100644 index f1dd61d..0000000 --- a/libcorkscrew/backtrace.c +++ /dev/null @@ -1,335 +0,0 @@ -/* - * 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 <stdlib.h> -#include <string.h> -#include <pthread.h> -#include <unwind.h> -#include <cutils/log.h> -#include <cutils/atomic.h> - -#define __USE_GNU // For dladdr(3) in glibc. -#include <dlfcn.h> - -#if defined(__BIONIC__) - -// Bionic implements and exports gettid but only implements tgkill. -extern int tgkill(int tgid, int tid, int sig); - -#elif defined(__APPLE__) - -#include <sys/syscall.h> - -// Mac OS >= 10.6 has a system call equivalent to Linux's gettid(). -static pid_t gettid() { - return syscall(SYS_thread_selfid); -} - -#else - -// glibc doesn't implement or export either gettid or tgkill. - -#include <unistd.h> -#include <sys/syscall.h> - -static pid_t gettid() { - return syscall(__NR_gettid); -} - -static int tgkill(int tgid, int tid, int sig) { - return syscall(__NR_tgkill, tgid, tid, sig); -} - -#endif - -typedef struct { - backtrace_frame_t* backtrace; - size_t ignore_depth; - size_t max_depth; - size_t ignored_frames; - size_t returned_frames; - memory_t memory; -} 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(rewind_pc_arch(&state->memory, 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) { - ALOGV("Unwinding current thread %d.", gettid()); - - map_info_t* milist = acquire_my_map_info_list(); - - 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; - init_memory(&state.memory, milist); - - _Unwind_Reason_Code rc = _Unwind_Backtrace(unwind_backtrace_callback, &state); - - release_my_map_info_list(milist); - - if (state.returned_frames) { - return state.returned_frames; - } - return rc == _URC_END_OF_STACK ? 0 : -1; -} - -#ifdef CORKSCREW_HAVE_ARCH -static const int32_t STATE_DUMPING = -1; -static const int32_t STATE_DONE = -2; -static const int32_t STATE_CANCEL = -3; - -static pthread_mutex_t g_unwind_signal_mutex = PTHREAD_MUTEX_INITIALIZER; -static volatile struct { - int32_t tid_state; - const map_info_t* map_info_list; - backtrace_frame_t* backtrace; - size_t ignore_depth; - size_t max_depth; - size_t returned_frames; -} g_unwind_signal_state; - -static void unwind_backtrace_thread_signal_handler(int n __attribute__((unused)), siginfo_t* siginfo, void* sigcontext) { - if (!android_atomic_acquire_cas(gettid(), STATE_DUMPING, &g_unwind_signal_state.tid_state)) { - g_unwind_signal_state.returned_frames = unwind_backtrace_signal_arch( - siginfo, sigcontext, - g_unwind_signal_state.map_info_list, - g_unwind_signal_state.backtrace, - g_unwind_signal_state.ignore_depth, - g_unwind_signal_state.max_depth); - android_atomic_release_store(STATE_DONE, &g_unwind_signal_state.tid_state); - } else { - ALOGV("Received spurious SIGURG on thread %d that was intended for thread %d.", - gettid(), android_atomic_acquire_load(&g_unwind_signal_state.tid_state)); - } -} -#endif - -ssize_t unwind_backtrace_thread(pid_t tid, backtrace_frame_t* backtrace, - size_t ignore_depth, size_t max_depth) { - if (tid == gettid()) { - return unwind_backtrace(backtrace, ignore_depth + 1, max_depth); - } - - ALOGV("Unwinding thread %d from thread %d.", tid, gettid()); - - // TODO: there's no tgkill(2) on Mac OS, so we'd either need the - // mach_port_t or the pthread_t rather than the tid. -#if defined(CORKSCREW_HAVE_ARCH) && !defined(__APPLE__) - 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 | SA_ONSTACK; - sigemptyset(&act.sa_mask); - - pthread_mutex_lock(&g_unwind_signal_mutex); - map_info_t* milist = acquire_my_map_info_list(); - - ssize_t frames = -1; - if (!sigaction(SIGURG, &act, &oact)) { - g_unwind_signal_state.map_info_list = milist; - 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; - android_atomic_release_store(tid, &g_unwind_signal_state.tid_state); - - // Signal the specific thread that we want to dump. - int32_t tid_state = tid; - if (tgkill(getpid(), tid, SIGURG)) { - ALOGV("Failed to send SIGURG to thread %d.", tid); - } else { - // Wait for the other thread to start dumping the stack, or time out. - int wait_millis = 250; - for (;;) { - tid_state = android_atomic_acquire_load(&g_unwind_signal_state.tid_state); - if (tid_state != tid) { - break; - } - if (wait_millis--) { - ALOGV("Waiting for thread %d to start dumping the stack...", tid); - usleep(1000); - } else { - ALOGV("Timed out waiting for thread %d to start dumping the stack.", tid); - break; - } - } - } - - // Try to cancel the dump if it has not started yet. - if (tid_state == tid) { - if (!android_atomic_acquire_cas(tid, STATE_CANCEL, &g_unwind_signal_state.tid_state)) { - ALOGV("Canceled thread %d stack dump.", tid); - tid_state = STATE_CANCEL; - } else { - tid_state = android_atomic_acquire_load(&g_unwind_signal_state.tid_state); - } - } - - // Wait indefinitely for the dump to finish or be canceled. - // We cannot apply a timeout here because the other thread is accessing state that - // is owned by this thread, such as milist. It should not take very - // long to take the dump once started. - while (tid_state == STATE_DUMPING) { - ALOGV("Waiting for thread %d to finish dumping the stack...", tid); - usleep(1000); - tid_state = android_atomic_acquire_load(&g_unwind_signal_state.tid_state); - } - - if (tid_state == STATE_DONE) { - frames = g_unwind_signal_state.returned_frames; - } - - sigaction(SIGURG, &oact, NULL); - } - - release_my_map_info_list(milist); - 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->relative_symbol_addr = 0; - symbol->map_name = NULL; - symbol->symbol_name = NULL; - symbol->demangled_name = NULL; -} - -void get_backtrace_symbols(const backtrace_frame_t* backtrace, size_t frames, - backtrace_symbol_t* backtrace_symbols) { - map_info_t* milist = acquire_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; - if (mi->name[0]) { - symbol->map_name = strdup(mi->name); - } - Dl_info info; - if (dladdr((const void*)frame->absolute_pc, &info) && info.dli_sname) { - symbol->relative_symbol_addr = (uintptr_t)info.dli_saddr - - (uintptr_t)info.dli_fbase; - symbol->symbol_name = strdup(info.dli_sname); - symbol->demangled_name = demangle_symbol_name(symbol->symbol_name); - } - } - } - release_my_map_info_list(milist); -} - -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; - if (mi->name[0]) { - symbol->map_name = strdup(mi->name); - } - } - if (s) { - symbol->relative_symbol_addr = s->start; - symbol->symbol_name = strdup(s->name); - symbol->demangled_name = demangle_symbol_name(symbol->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->map_name); - free(symbol->symbol_name); - free(symbol->demangled_name); - init_backtrace_symbol(symbol, 0); - } -} - -void format_backtrace_line(unsigned frameNumber, const backtrace_frame_t* frame __attribute__((unused)), - const backtrace_symbol_t* symbol, char* buffer, size_t bufferSize) { - const char* mapName = symbol->map_name ? symbol->map_name : "<unknown>"; - const char* symbolName = symbol->demangled_name ? symbol->demangled_name : symbol->symbol_name; - int fieldWidth = (bufferSize - 80) / 2; - if (symbolName) { - uint32_t pc_offset = symbol->relative_pc - symbol->relative_symbol_addr; - if (pc_offset) { - snprintf(buffer, bufferSize, "#%02u pc %08x %.*s (%.*s+%u)", - frameNumber, (unsigned int) symbol->relative_pc, - fieldWidth, mapName, fieldWidth, symbolName, pc_offset); - } else { - snprintf(buffer, bufferSize, "#%02u pc %08x %.*s (%.*s)", - frameNumber, (unsigned int) symbol->relative_pc, - fieldWidth, mapName, fieldWidth, symbolName); - } - } else { - snprintf(buffer, bufferSize, "#%02u pc %08x %.*s", - frameNumber, (unsigned int) symbol->relative_pc, - fieldWidth, mapName); - } -} |