1275970Scy/* 2275970Scy * Copyright (C) 2009 Internet Systems Consortium, Inc. ("ISC") 3275970Scy * 4275970Scy * Permission to use, copy, modify, and/or distribute this software for any 5275970Scy * purpose with or without fee is hereby granted, provided that the above 6275970Scy * copyright notice and this permission notice appear in all copies. 7275970Scy * 8275970Scy * THE SOFTWARE IS PROVIDED "AS IS" AND ISC DISCLAIMS ALL WARRANTIES WITH 9275970Scy * REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY 10275970Scy * AND FITNESS. IN NO EVENT SHALL ISC BE LIABLE FOR ANY SPECIAL, DIRECT, 11275970Scy * INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM 12275970Scy * LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE 13275970Scy * OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR 14275970Scy * PERFORMANCE OF THIS SOFTWARE. 15275970Scy */ 16275970Scy 17275970Scy/* $Id: backtrace.h,v 1.2 2009/09/01 18:40:25 jinmei Exp $ */ 18275970Scy 19275970Scy/*! \file isc/backtrace.h 20275970Scy * \brief provide a back trace of the running process to help debug problems. 21275970Scy * 22275970Scy * This module tries to get a back trace of the process using some platform 23275970Scy * dependent way when available. It also manages an internal symbol table 24275970Scy * that maps function addresses used in the process to their textual symbols. 25275970Scy * This module is expected to be used to help debug when some fatal error 26275970Scy * happens. 27275970Scy * 28275970Scy * IMPORTANT NOTE: since the (major) intended use case of this module is 29275970Scy * dumping a back trace on a fatal error, normally followed by self termination, 30275970Scy * functions defined in this module generally doesn't employ assertion checks 31275970Scy * (if it did, a program bug could cause infinite recursive calls to a 32275970Scy * backtrace function). These functions still perform minimal checks and return 33275970Scy * ISC_R_FAILURE if they detect an error, but the caller should therefore be 34275970Scy * very careful about the use of these functions, and generally discouraged to 35275970Scy * use them except in an exit path. The exception is 36275970Scy * isc_backtrace_getsymbolfromindex(), which is expected to be used in a 37275970Scy * non-error-handling context and validates arguments with assertion checks. 38275970Scy */ 39275970Scy 40275970Scy#ifndef ISC_BACKTRACE_H 41275970Scy#define ISC_BACKTRACE_H 1 42275970Scy 43275970Scy/*** 44275970Scy *** Imports 45275970Scy ***/ 46275970Scy 47275970Scy#include <isc/types.h> 48275970Scy 49275970Scy/*** 50275970Scy *** Types 51275970Scy ***/ 52275970Scystruct isc_backtrace_symmap { 53275970Scy void *addr; 54275970Scy const char *symbol; 55275970Scy}; 56275970Scy 57275970Scyextern const int isc__backtrace_nsymbols; 58275970Scyextern const isc_backtrace_symmap_t isc__backtrace_symtable[]; 59275970Scy 60275970Scy/*** 61275970Scy *** Functions 62275970Scy ***/ 63275970Scy 64275970ScyISC_LANG_BEGINDECLS 65275970Scyisc_result_t 66275970Scyisc_backtrace_gettrace(void **addrs, int maxaddrs, int *nframes); 67275970Scy/*%< 68275970Scy * Get a back trace of the running process above this function itself. On 69275970Scy * success, addrs[i] will store the address of the call point of the i-th 70275970Scy * stack frame (addrs[0] is the caller of this function). *nframes will store 71275970Scy * the total number of frames. 72275970Scy * 73275970Scy * Requires (note that these are not ensured by assertion checks, see above): 74275970Scy * 75275970Scy *\li 'addrs' is a valid array containing at least 'maxaddrs' void * entries. 76275970Scy * 77275970Scy *\li 'nframes' must be non NULL. 78275970Scy * 79275970Scy * Returns: 80275970Scy * 81275970Scy *\li #ISC_R_SUCCESS 82275970Scy *\li #ISC_R_FAILURE 83275970Scy *\li #ISC_R_NOTFOUND 84275970Scy *\li #ISC_R_NOTIMPLEMENTED 85275970Scy */ 86275970Scy 87275970Scyisc_result_t 88280849Scyisc_backtrace_getsymbolfromindex(int idx, const void **addrp, 89275970Scy const char **symbolp); 90275970Scy/*%< 91275970Scy * Returns the content of the internal symbol table of the given index. 92275970Scy * On success, *addrsp and *symbolp point to the address and the symbol of 93280849Scy * the 'index'th entry of the table, respectively. If 'idx' is not in the 94275970Scy * range of the symbol table, ISC_R_RANGE will be returned. 95275970Scy * 96275970Scy * Requires 97275970Scy * 98275970Scy *\li 'addrp' must be non NULL && '*addrp' == NULL. 99275970Scy * 100275970Scy *\li 'symbolp' must be non NULL && '*symbolp' == NULL. 101275970Scy * 102275970Scy * Returns: 103275970Scy * 104275970Scy *\li #ISC_R_SUCCESS 105275970Scy *\li #ISC_R_RANGE 106275970Scy */ 107275970Scy 108275970Scyisc_result_t 109275970Scyisc_backtrace_getsymbol(const void *addr, const char **symbolp, 110275970Scy unsigned long *offsetp); 111275970Scy/*%< 112275970Scy * Searches the internal symbol table for the symbol that most matches the 113275970Scy * given 'addr'. On success, '*symbolp' will point to the name of function 114275970Scy * to which the address 'addr' belong, and '*offsetp' will store the offset 115275970Scy * from the function's entry address to 'addr'. 116275970Scy * 117275970Scy * Requires (note that these are not ensured by assertion checks, see above): 118275970Scy * 119275970Scy *\li 'symbolp' must be non NULL && '*symbolp' == NULL. 120275970Scy * 121275970Scy *\li 'offsetp' must be non NULL. 122275970Scy * 123275970Scy * Returns: 124275970Scy * 125275970Scy *\li #ISC_R_SUCCESS 126275970Scy *\li #ISC_R_FAILURE 127275970Scy *\li #ISC_R_NOTFOUND 128275970Scy */ 129275970ScyISC_LANG_ENDDECLS 130275970Scy 131275970Scy#endif /* ISC_BACKTRACE_H */ 132