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 #ifndef _BACKTRACE_BACKTRACE_H 18 #define _BACKTRACE_BACKTRACE_H 19 20 #include <inttypes.h> 21 #include <stdint.h> 22 23 #include <string> 24 #include <vector> 25 26 #include <backtrace/backtrace_constants.h> 27 #include <backtrace/BacktraceMap.h> 28 29 #if __LP64__ 30 #define PRIPTR "016" PRIxPTR 31 typedef uint64_t word_t; 32 #else 33 #define PRIPTR "08" PRIxPTR 34 typedef uint32_t word_t; 35 #endif 36 37 struct backtrace_frame_data_t { 38 size_t num; // The current fame number. 39 uintptr_t pc; // The absolute pc. 40 uintptr_t sp; // The top of the stack. 41 size_t stack_size; // The size of the stack, zero indicate an unknown stack size. 42 const backtrace_map_t* map; // The map associated with the given pc. 43 std::string func_name; // The function name associated with this pc, NULL if not found. 44 uintptr_t func_offset; // pc relative to the start of the function, only valid if func_name is not NULL. 45 }; 46 47 // Forward declarations. 48 class BacktraceImpl; 49 50 #if defined(__APPLE__) 51 struct __darwin_ucontext; 52 typedef __darwin_ucontext ucontext_t; 53 #else 54 struct ucontext; 55 typedef ucontext ucontext_t; 56 #endif 57 58 class Backtrace { 59 public: 60 // Create the correct Backtrace object based on what is to be unwound. 61 // If pid < 0 or equals the current pid, then the Backtrace object 62 // corresponds to the current process. 63 // If pid < 0 or equals the current pid and tid >= 0, then the Backtrace 64 // object corresponds to a thread in the current process. 65 // If pid >= 0 and tid < 0, then the Backtrace object corresponds to a 66 // different process. 67 // Tracing a thread in a different process is not supported. 68 // If map is NULL, then create the map and manage it internally. 69 // If map is not NULL, the map is still owned by the caller. 70 static Backtrace* Create(pid_t pid, pid_t tid, BacktraceMap* map = NULL); 71 72 virtual ~Backtrace(); 73 74 // Get the current stack trace and store in the backtrace_ structure. 75 virtual bool Unwind(size_t num_ignore_frames, ucontext_t* context = NULL); 76 77 // Get the function name and offset into the function given the pc. 78 // If the string is empty, then no valid function name was found. 79 virtual std::string GetFunctionName(uintptr_t pc, uintptr_t* offset); 80 81 // Find the map associated with the given pc. 82 virtual const backtrace_map_t* FindMap(uintptr_t pc); 83 84 // Read the data at a specific address. 85 virtual bool ReadWord(uintptr_t ptr, word_t* out_value) = 0; 86 87 // Create a string representing the formatted line of backtrace information 88 // for a single frame. 89 virtual std::string FormatFrameData(size_t frame_num); 90 virtual std::string FormatFrameData(const backtrace_frame_data_t* frame); 91 Pid()92 pid_t Pid() { return pid_; } Tid()93 pid_t Tid() { return tid_; } NumFrames()94 size_t NumFrames() { return frames_.size(); } 95 GetFrame(size_t frame_num)96 const backtrace_frame_data_t* GetFrame(size_t frame_num) { 97 if (frame_num >= frames_.size()) { 98 return NULL; 99 } 100 return &frames_[frame_num]; 101 } 102 103 typedef std::vector<backtrace_frame_data_t>::iterator iterator; begin()104 iterator begin() { return frames_.begin(); } end()105 iterator end() { return frames_.end(); } 106 107 typedef std::vector<backtrace_frame_data_t>::const_iterator const_iterator; begin()108 const_iterator begin() const { return frames_.begin(); } end()109 const_iterator end() const { return frames_.end(); } 110 GetMap()111 BacktraceMap* GetMap() { return map_; } 112 113 protected: 114 Backtrace(BacktraceImpl* impl, pid_t pid, BacktraceMap* map); 115 116 virtual bool VerifyReadWordArgs(uintptr_t ptr, word_t* out_value); 117 118 bool BuildMap(); 119 120 pid_t pid_; 121 pid_t tid_; 122 123 BacktraceMap* map_; 124 bool map_shared_; 125 126 std::vector<backtrace_frame_data_t> frames_; 127 128 BacktraceImpl* impl_; 129 130 friend class BacktraceImpl; 131 }; 132 133 #endif // _BACKTRACE_BACKTRACE_H 134