1 /* $NetBSD: backtrace.h,v 1.4 2014/12/10 04:38:00 christos Exp $ */ 2 3 /* 4 * Copyright (C) 2009 Internet Systems Consortium, Inc. ("ISC") 5 * 6 * Permission to use, copy, modify, and/or distribute this software for any 7 * purpose with or without fee is hereby granted, provided that the above 8 * copyright notice and this permission notice appear in all copies. 9 * 10 * THE SOFTWARE IS PROVIDED "AS IS" AND ISC DISCLAIMS ALL WARRANTIES WITH 11 * REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY 12 * AND FITNESS. IN NO EVENT SHALL ISC BE LIABLE FOR ANY SPECIAL, DIRECT, 13 * INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM 14 * LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE 15 * OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR 16 * PERFORMANCE OF THIS SOFTWARE. 17 */ 18 19 /* Id: backtrace.h,v 1.2 2009/09/01 18:40:25 jinmei Exp */ 20 21 /*! \file isc/backtrace.h 22 * \brief provide a back trace of the running process to help debug problems. 23 * 24 * This module tries to get a back trace of the process using some platform 25 * dependent way when available. It also manages an internal symbol table 26 * that maps function addresses used in the process to their textual symbols. 27 * This module is expected to be used to help debug when some fatal error 28 * happens. 29 * 30 * IMPORTANT NOTE: since the (major) intended use case of this module is 31 * dumping a back trace on a fatal error, normally followed by self termination, 32 * functions defined in this module generally doesn't employ assertion checks 33 * (if it did, a program bug could cause infinite recursive calls to a 34 * backtrace function). These functions still perform minimal checks and return 35 * ISC_R_FAILURE if they detect an error, but the caller should therefore be 36 * very careful about the use of these functions, and generally discouraged to 37 * use them except in an exit path. The exception is 38 * isc_backtrace_getsymbolfromindex(), which is expected to be used in a 39 * non-error-handling context and validates arguments with assertion checks. 40 */ 41 42 #ifndef ISC_BACKTRACE_H 43 #define ISC_BACKTRACE_H 1 44 45 /*** 46 *** Imports 47 ***/ 48 49 #include <isc/types.h> 50 51 /*** 52 *** Types 53 ***/ 54 struct isc_backtrace_symmap { 55 void *addr; 56 const char *symbol; 57 }; 58 59 extern const int isc__backtrace_nsymbols; 60 extern const isc_backtrace_symmap_t isc__backtrace_symtable[]; 61 62 /*** 63 *** Functions 64 ***/ 65 66 ISC_LANG_BEGINDECLS 67 isc_result_t 68 isc_backtrace_gettrace(void **addrs, int maxaddrs, int *nframes); 69 /*%< 70 * Get a back trace of the running process above this function itself. On 71 * success, addrs[i] will store the address of the call point of the i-th 72 * stack frame (addrs[0] is the caller of this function). *nframes will store 73 * the total number of frames. 74 * 75 * Requires (note that these are not ensured by assertion checks, see above): 76 * 77 *\li 'addrs' is a valid array containing at least 'maxaddrs' void * entries. 78 * 79 *\li 'nframes' must be non NULL. 80 * 81 * Returns: 82 * 83 *\li #ISC_R_SUCCESS 84 *\li #ISC_R_FAILURE 85 *\li #ISC_R_NOTFOUND 86 *\li #ISC_R_NOTIMPLEMENTED 87 */ 88 89 isc_result_t 90 isc_backtrace_getsymbolfromindex(int index, const void **addrp, 91 const char **symbolp); 92 /*%< 93 * Returns the content of the internal symbol table of the given index. 94 * On success, *addrsp and *symbolp point to the address and the symbol of 95 * the 'index'th entry of the table, respectively. If 'index' is not in the 96 * range of the symbol table, ISC_R_RANGE will be returned. 97 * 98 * Requires 99 * 100 *\li 'addrp' must be non NULL && '*addrp' == NULL. 101 * 102 *\li 'symbolp' must be non NULL && '*symbolp' == NULL. 103 * 104 * Returns: 105 * 106 *\li #ISC_R_SUCCESS 107 *\li #ISC_R_RANGE 108 */ 109 110 isc_result_t 111 isc_backtrace_getsymbol(const void *addr, const char **symbolp, 112 unsigned long *offsetp); 113 /*%< 114 * Searches the internal symbol table for the symbol that most matches the 115 * given 'addr'. On success, '*symbolp' will point to the name of function 116 * to which the address 'addr' belong, and '*offsetp' will store the offset 117 * from the function's entry address to 'addr'. 118 * 119 * Requires (note that these are not ensured by assertion checks, see above): 120 * 121 *\li 'symbolp' must be non NULL && '*symbolp' == NULL. 122 * 123 *\li 'offsetp' must be non NULL. 124 * 125 * Returns: 126 * 127 *\li #ISC_R_SUCCESS 128 *\li #ISC_R_FAILURE 129 *\li #ISC_R_NOTFOUND 130 */ 131 ISC_LANG_ENDDECLS 132 133 #endif /* ISC_BACKTRACE_H */ 134