backtrace.h revision f0c5872637a63e28e3cd314cfc915c07f76df9c6 
1/*
2 * Copyright (C) 2011 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/* A stack unwinder. */
18
19#ifndef _CORKSCREW_BACKTRACE_H
20#define _CORKSCREW_BACKTRACE_H
21
22#ifdef __cplusplus
23extern "C" {
24#endif
25
26#include <sys/types.h>
27#include <corkscrew/ptrace.h>
28#include <corkscrew/map_info.h>
29#include <corkscrew/symbol_table.h>
30
31/*
32 * Describes a single frame of a backtrace.
33 */
34typedef struct {
35    uintptr_t absolute_pc;     /* absolute PC offset */
36    uintptr_t stack_top;       /* top of stack for this frame */
37    size_t stack_size;         /* size of this stack frame */
38} backtrace_frame_t;
39
40/*
41 * Describes the symbols associated with a backtrace frame.
42 */
43typedef struct {
44    uintptr_t relative_pc;       /* relative PC offset from the start of the library,
45                                    or the absolute PC if the library is unknown */
46    char* map_name;              /* executable or library name, or NULL if unknown */
47    char* name;                  /* symbol name, or NULL if unknown */
48    char* demangled_name;        /* demangled symbol name, or NULL if unknown */
49} backtrace_symbol_t;
50
51/*
52 * Unwinds the call stack for the current thread of execution.
53 * Populates the backtrace array with the program counters from the call stack.
54 * Returns the number of frames collected, or -1 if an error occurred.
55 */
56ssize_t unwind_backtrace(backtrace_frame_t* backtrace, size_t ignore_depth, size_t max_depth);
57
58/*
59 * Unwinds the call stack for a thread within this process.
60 * Populates the backtrace array with the program counters from the call stack.
61 * Returns the number of frames collected, or -1 if an error occurred.
62 *
63 * The task is briefly suspended while the backtrace is being collected.
64 */
65ssize_t unwind_backtrace_thread(pid_t tid, backtrace_frame_t* backtrace,
66        size_t ignore_depth, size_t max_depth);
67
68/*
69 * Unwinds the call stack of a task within a remote process using ptrace().
70 * Populates the backtrace array with the program counters from the call stack.
71 * Returns the number of frames collected, or -1 if an error occurred.
72 */
73ssize_t unwind_backtrace_ptrace(pid_t tid, const ptrace_context_t* context,
74        backtrace_frame_t* backtrace, size_t ignore_depth, size_t max_depth);
75
76/*
77 * Gets the symbols for each frame of a backtrace.
78 * The symbols array must be big enough to hold one symbol record per frame.
79 * The symbols must later be freed using free_backtrace_symbols.
80 */
81void get_backtrace_symbols(const backtrace_frame_t* backtrace, size_t frames,
82        backtrace_symbol_t* backtrace_symbols);
83
84/*
85 * Gets the symbols for each frame of a backtrace from a remote process.
86 * The symbols array must be big enough to hold one symbol record per frame.
87 * The symbols must later be freed using free_backtrace_symbols.
88 */
89void get_backtrace_symbols_ptrace(const ptrace_context_t* context,
90        const backtrace_frame_t* backtrace, size_t frames,
91        backtrace_symbol_t* backtrace_symbols);
92
93/*
94 * Frees the storage associated with backtrace symbols.
95 */
96void free_backtrace_symbols(backtrace_symbol_t* backtrace_symbols, size_t frames);
97
98#ifdef __cplusplus
99}
100#endif
101
102#endif // _CORKSCREW_BACKTRACE_H
103