Christopher Ferris | 7fb2287 | 2013-09-27 12:43:15 -0700 | [diff] [blame^] | 1 | /* |
| 2 | * Copyright (C) 2013 The Android Open Source Project |
| 3 | * |
| 4 | * Licensed under the Apache License, Version 2.0 (the "License"); |
| 5 | * you may not use this file except in compliance with the License. |
| 6 | * You may obtain a copy of the License at |
| 7 | * |
| 8 | * http://www.apache.org/licenses/LICENSE-2.0 |
| 9 | * |
| 10 | * Unless required by applicable law or agreed to in writing, software |
| 11 | * distributed under the License is distributed on an "AS IS" BASIS, |
| 12 | * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| 13 | * See the License for the specific language governing permissions and |
| 14 | * limitations under the License. |
| 15 | */ |
| 16 | |
| 17 | #define LOG_TAG "libbacktrace" |
| 18 | |
| 19 | #include <sys/ptrace.h> |
| 20 | #include <string.h> |
| 21 | |
| 22 | #include <cutils/log.h> |
| 23 | #include <backtrace/backtrace.h> |
| 24 | |
| 25 | #include <libunwind.h> |
| 26 | #include <libunwind-ptrace.h> |
| 27 | |
| 28 | #include "common.h" |
| 29 | #include "demangle.h" |
| 30 | |
| 31 | typedef struct { |
| 32 | unw_addr_space_t addr_space; |
| 33 | struct UPT_info* upt_info; |
| 34 | } backtrace_private_t; |
| 35 | |
| 36 | static bool remote_get_frames(backtrace_t* backtrace) { |
| 37 | backtrace_private_t* data = (backtrace_private_t*)backtrace->private_data; |
| 38 | unw_cursor_t cursor; |
| 39 | int ret = unw_init_remote(&cursor, data->addr_space, data->upt_info); |
| 40 | if (ret < 0) { |
| 41 | ALOGW("remote_get_frames: unw_init_remote failed %d\n", ret); |
| 42 | return false; |
| 43 | } |
| 44 | |
| 45 | backtrace_frame_data_t* frame; |
| 46 | bool returnValue = true; |
| 47 | backtrace->num_frames = 0; |
| 48 | uintptr_t map_start; |
| 49 | do { |
| 50 | frame = &backtrace->frames[backtrace->num_frames]; |
| 51 | frame->stack_size = 0; |
| 52 | frame->map_name = NULL; |
| 53 | frame->map_offset = 0; |
| 54 | frame->proc_name = NULL; |
| 55 | frame->proc_offset = 0; |
| 56 | |
| 57 | ret = unw_get_reg(&cursor, UNW_REG_IP, &frame->pc); |
| 58 | if (ret < 0) { |
| 59 | ALOGW("remote_get_frames: Failed to read IP %d\n", ret); |
| 60 | returnValue = false; |
| 61 | break; |
| 62 | } |
| 63 | ret = unw_get_reg(&cursor, UNW_REG_SP, &frame->sp); |
| 64 | if (ret < 0) { |
| 65 | ALOGW("remote_get_frames: Failed to read SP %d\n", ret); |
| 66 | returnValue = false; |
| 67 | break; |
| 68 | } |
| 69 | if (backtrace->num_frames) { |
| 70 | backtrace_frame_data_t* prev = &backtrace->frames[backtrace->num_frames-1]; |
| 71 | prev->stack_size = frame->sp - prev->sp; |
| 72 | } |
| 73 | |
| 74 | frame->proc_name = backtrace_get_proc_name(backtrace, frame->pc, &frame->proc_offset); |
| 75 | |
| 76 | frame->map_name = backtrace_get_map_info(backtrace, frame->pc, &map_start); |
| 77 | if (frame->map_name) { |
| 78 | frame->map_offset = frame->pc - map_start; |
| 79 | } |
| 80 | |
| 81 | backtrace->num_frames++; |
| 82 | ret = unw_step (&cursor); |
| 83 | } while (ret > 0 && backtrace->num_frames < MAX_BACKTRACE_FRAMES); |
| 84 | |
| 85 | return returnValue; |
| 86 | } |
| 87 | |
| 88 | bool remote_get_data(backtrace_t* backtrace) { |
| 89 | backtrace_private_t* data = (backtrace_private_t*)malloc(sizeof(backtrace_private_t)); |
| 90 | if (!data) { |
| 91 | ALOGW("remote_get_data: Failed to allocate memory.\n"); |
| 92 | backtrace_free_data(backtrace); |
| 93 | return false; |
| 94 | } |
| 95 | data->addr_space = NULL; |
| 96 | data->upt_info = NULL; |
| 97 | |
| 98 | backtrace->private_data = data; |
| 99 | data->addr_space = unw_create_addr_space(&_UPT_accessors, 0); |
| 100 | if (!data->addr_space) { |
| 101 | ALOGW("remote_get_data: Failed to create unw address space.\n"); |
| 102 | backtrace_free_data(backtrace); |
| 103 | return false; |
| 104 | } |
| 105 | |
| 106 | data->upt_info = _UPT_create(backtrace->tid); |
| 107 | if (!data->upt_info) { |
| 108 | ALOGW("remote_get_data: Failed to create upt info.\n"); |
| 109 | backtrace_free_data(backtrace); |
| 110 | return false; |
| 111 | } |
| 112 | |
| 113 | if (!remote_get_frames(backtrace)) { |
| 114 | backtrace_free_data(backtrace); |
| 115 | return false; |
| 116 | } |
| 117 | |
| 118 | return true; |
| 119 | } |
| 120 | |
| 121 | void remote_free_data(backtrace_t* backtrace) { |
| 122 | if (backtrace->private_data) { |
| 123 | backtrace_private_t* data = (backtrace_private_t*)backtrace->private_data; |
| 124 | if (data->upt_info) { |
| 125 | _UPT_destroy(data->upt_info); |
| 126 | data->upt_info = NULL; |
| 127 | } |
| 128 | if (data->addr_space) { |
| 129 | unw_destroy_addr_space(data->addr_space); |
| 130 | } |
| 131 | |
| 132 | free(backtrace->private_data); |
| 133 | backtrace->private_data = NULL; |
| 134 | } |
| 135 | } |
| 136 | |
| 137 | char* remote_get_proc_name(const backtrace_t* backtrace, uintptr_t pc, |
| 138 | uintptr_t* offset) { |
| 139 | backtrace_private_t* data = (backtrace_private_t*)backtrace->private_data; |
| 140 | char buf[512]; |
| 141 | |
| 142 | if (unw_get_proc_name_by_ip(data->addr_space, pc, buf, sizeof(buf), offset, |
| 143 | data->upt_info) >= 0 && buf[0] != '\0') { |
| 144 | char* symbol = demangle_symbol_name(buf); |
| 145 | if (!symbol) { |
| 146 | symbol = strdup(buf); |
| 147 | } |
| 148 | return symbol; |
| 149 | } |
| 150 | return NULL; |
| 151 | } |