1 /* 2 3 Copyright (C) 2000-2005 Silicon Graphics, Inc. All Rights Reserved. 4 Portions Copyright (C) 2008-2014 David Anderson. All Rights Reserved. 5 6 This program is free software; you can redistribute it and/or modify it 7 under the terms of version 2.1 of the GNU Lesser General Public License 8 as published by the Free Software Foundation. 9 10 This program is distributed in the hope that it would be useful, but 11 WITHOUT ANY WARRANTY; without even the implied warranty of 12 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. 13 14 Further, this software is distributed without any warranty that it is 15 free of the rightful claim of any third person regarding infringement 16 or the like. Any license provided herein, whether implied or 17 otherwise, applies only to this software file. Patent licenses, if 18 any, provided herein do not apply to combinations of this program with 19 other software, or any other product whatsoever. 20 21 You should have received a copy of the GNU Lesser General Public 22 License along with this program; if not, write the Free Software 23 Foundation, Inc., 51 Franklin Street - Fifth Floor, Boston MA 02110-1301, 24 USA. 25 26 */ 27 28 #include "config.h" 29 #include <stdio.h> 30 #include <sys/stat.h> 31 #include <sys/types.h> 32 #ifdef HAVE_STDLIB_H 33 #include <stdlib.h> 34 #endif /* HAVE_STDLIB_H */ 35 #include "dwarf_incl.h" 36 #include "dwarf_alloc.h" 37 #include "dwarfstring.h" 38 #include "dwarf_error.h" 39 40 /* Array to hold string representation of errors. Any time a 41 define is added to the list in libdwarf.h, a string should be 42 added to this Array 43 */ 44 #include "dwarf_errmsg_list.h" 45 46 /* This function performs error handling as described in the 47 libdwarf consumer document section 3. Dbg is the Dwarf_debug 48 structure being processed. Error is a pointer to the pointer 49 to the error descriptor that will be returned. Errval is an 50 error code listed in dwarf_error.h. 51 52 If the malloc arena is exhausted we return a pointer to 53 a special static error record. This special singleton 54 is mostly ignored by dwarf_dealloc(). 55 Users should not be storing Dwarf_Error pointers 56 for long so this singleton is only going to cause 57 confusion when callers try to save an out-of-memory 58 Dwarf_Error pointer. 59 The _dwarf_failsafe_error is intended to 60 be an improvement over an abort() call. 61 The failsafe means we will not abort due to 62 a Dwarf_Error struct creation. 63 */ 64 65 /* The user provides an explanatory string, the error 66 number itself explains little. 67 This prepends DW_DLE_USER_DECLARED_ERROR to the 68 caller-provided string. 69 New in April, 2020 . Used by dwarfdump in a few 70 circumstances. */ 71 void 72 dwarf_error_creation(Dwarf_Debug dbg, 73 Dwarf_Error *err, 74 char *errmsg) 75 { 76 dwarfstring m; 77 if(!dbg) { 78 return; 79 } 80 dwarfstring_constructor(&m); 81 dwarfstring_append(&m,"DW_DLE_USER_DECLARED_ERROR: "); 82 dwarfstring_append(&m,errmsg); 83 _dwarf_error_string(dbg,err, 84 DW_DLE_USER_DECLARED_ERROR, 85 dwarfstring_string(&m)); 86 dwarfstring_destructor(&m); 87 } 88 89 90 void 91 _dwarf_error(Dwarf_Debug dbg, Dwarf_Error * error, 92 Dwarf_Signed errval) 93 { 94 _dwarf_error_string(dbg,error,errval,0); 95 } 96 void 97 _dwarf_error_string(Dwarf_Debug dbg, Dwarf_Error * error, 98 Dwarf_Signed errval,char *msg) 99 { 100 Dwarf_Error errptr; 101 102 /* Allow NULL dbg on entry, since sometimes that can happen and we 103 want to report the upper-level error, not this one. */ 104 if (error) { 105 /* If dbg is NULL, use the alternate error struct. However, 106 this will overwrite the earlier error. */ 107 if (dbg) { 108 errptr = 109 (Dwarf_Error) _dwarf_get_alloc(dbg, DW_DLA_ERROR, 1); 110 if (!errptr) { 111 errptr = &_dwarf_failsafe_error; 112 errptr->er_static_alloc = DE_STATIC; 113 } else { 114 errptr->er_static_alloc = DE_STANDARD; 115 } 116 } else { 117 /* We have no dbg to work with. dwarf_init 118 failed. We hack 119 up a special area. */ 120 errptr = _dwarf_special_no_dbg_error_malloc(); 121 if (!errptr) { 122 errptr = &_dwarf_failsafe_error; 123 errptr->er_static_alloc = DE_STATIC; 124 } else { 125 errptr->er_static_alloc = DE_MALLOC; 126 } 127 } 128 errptr->er_errval = errval; 129 if (msg) { 130 dwarfstring *em = 0; 131 132 #ifdef DEBUG 133 printf("libdwarfdetector ALLOC creating error string %s errval %ld errptr 0x%lx \n",msg,(long)errval,(unsigned long)errptr); 134 #endif 135 em = (dwarfstring *)calloc(1,sizeof(dwarfstring)); 136 if (em) { 137 dwarfstring_constructor(em); 138 dwarfstring_append(em,msg); 139 errptr->er_msg = (void*)em; 140 } 141 } 142 *error = errptr; 143 return; 144 } 145 146 if (dbg != NULL && dbg->de_errhand != NULL) { 147 errptr = (Dwarf_Error) _dwarf_get_alloc(dbg, DW_DLA_ERROR, 1); 148 if (errptr == NULL) { 149 errptr = &_dwarf_failsafe_error; 150 errptr->er_static_alloc = DE_STATIC; 151 } 152 errptr->er_errval = errval; 153 dbg->de_errhand(errptr, dbg->de_errarg); 154 return; 155 } 156 fflush(stdout); 157 fprintf(stdout, 158 "\nNow abort() in libdwarf. " 159 "No error argument or handler available.\n"); 160 fflush(stdout); 161 abort(); 162 } 163 164 165 Dwarf_Unsigned 166 dwarf_errno(Dwarf_Error error) 167 { 168 if (!error) { 169 return (0); 170 } 171 return (error->er_errval); 172 } 173 174 char* 175 dwarf_errmsg_by_number(Dwarf_Unsigned errornum ) 176 { 177 if (errornum >= 178 (Dwarf_Signed)(sizeof(_dwarf_errmsgs) / sizeof(char *))) { 179 return "Dwarf_Error value out of range"; 180 } 181 return ((char *) _dwarf_errmsgs[errornum]); 182 } 183 184 185 /* 186 */ 187 char * 188 dwarf_errmsg(Dwarf_Error error) 189 { 190 if (!error) { 191 return "Dwarf_Error is NULL"; 192 } 193 if (error->er_msg) { 194 return dwarfstring_string(error->er_msg); 195 } 196 return dwarf_errmsg_by_number(error->er_errval); 197 } 198