1 /* Find a named variable or parameter within given scopes. 2 Copyright (C) 2005 Red Hat, Inc. 3 This file is part of Red Hat elfutils. 4 5 Red Hat elfutils is free software; you can redistribute it and/or modify 6 it under the terms of the GNU General Public License as published by the 7 Free Software Foundation; version 2 of the License. 8 9 Red Hat elfutils is distributed in the hope that it will be useful, but 10 WITHOUT ANY WARRANTY; without even the implied warranty of 11 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 12 General Public License for more details. 13 14 You should have received a copy of the GNU General Public License along 15 with Red Hat elfutils; if not, write to the Free Software Foundation, 16 Inc., 51 Franklin Street, Fifth Floor, Boston MA 02110-1301 USA. 17 18 In addition, as a special exception, Red Hat, Inc. gives You the 19 additional right to link the code of Red Hat elfutils with code licensed 20 under any Open Source Initiative certified open source license 21 (http://www.opensource.org/licenses/index.php) which requires the 22 distribution of source code with any binary distribution and to 23 distribute linked combinations of the two. Non-GPL Code permitted under 24 this exception must only link to the code of Red Hat elfutils through 25 those well defined interfaces identified in the file named EXCEPTION 26 found in the source code files (the "Approved Interfaces"). The files 27 of Non-GPL Code may instantiate templates or use macros or inline 28 functions from the Approved Interfaces without causing the resulting 29 work to be covered by the GNU General Public License. Only Red Hat, 30 Inc. may make changes or additions to the list of Approved Interfaces. 31 Red Hat's grant of this exception is conditioned upon your not adding 32 any new exceptions. If you wish to add a new Approved Interface or 33 exception, please contact Red Hat. You must obey the GNU General Public 34 License in all respects for all of the Red Hat elfutils code and other 35 code used in conjunction with Red Hat elfutils except the Non-GPL Code 36 covered by this exception. If you modify this file, you may extend this 37 exception to your version of the file, but you are not obligated to do 38 so. If you do not wish to provide this exception without modification, 39 you must delete this exception statement from your version and license 40 this file solely under the GPL without exception. 41 42 Red Hat elfutils is an included package of the Open Invention Network. 43 An included package of the Open Invention Network is a package for which 44 Open Invention Network licensees cross-license their patents. No patent 45 license is granted, either expressly or impliedly, by designation as an 46 included package. Should you wish to participate in the Open Invention 47 Network licensing program, please visit www.openinventionnetwork.com 48 <http://www.openinventionnetwork.com>. */ 49 50 #ifdef HAVE_CONFIG_H 51 # include <config.h> 52 #endif 53 54 #include <stdbool.h> 55 #include <string.h> 56 #include "libdwP.h" 57 #include <dwarf.h> 58 59 60 /* Find the containing CU's files. */ 61 static int 62 getfiles (Dwarf_Die *die, Dwarf_Files **files) 63 { 64 return INTUSE(dwarf_getsrcfiles) (&CUDIE (die->cu), files, NULL); 65 } 66 67 /* Fetch an attribute that should have a constant integer form. */ 68 static int 69 getattr (Dwarf_Die *die, int search_name, Dwarf_Word *value) 70 { 71 Dwarf_Attribute attr_mem; 72 return INTUSE(dwarf_formudata) (INTUSE(dwarf_attr) (die, search_name, 73 &attr_mem), value); 74 } 75 76 /* Search SCOPES[0..NSCOPES-1] for a variable called NAME. 77 Ignore the first SKIP_SHADOWS scopes that match the name. 78 If MATCH_FILE is not null, accept only declaration in that source file; 79 if MATCH_LINENO or MATCH_LINECOL are also nonzero, accept only declaration 80 at that line and column. 81 82 If successful, fill in *RESULT with the DIE of the variable found, 83 and return N where SCOPES[N] is the scope defining the variable. 84 Return -1 for errors or -2 for no matching variable found. */ 85 86 int 87 dwarf_getscopevar (Dwarf_Die *scopes, int nscopes, 88 const char *name, int skip_shadows, 89 const char *match_file, int match_lineno, int match_linecol, 90 Dwarf_Die *result) 91 { 92 /* Match against the given file name. */ 93 size_t match_file_len = match_file == NULL ? 0 : strlen (match_file); 94 bool lastfile_matches = false; 95 const char *lastfile = NULL; 96 inline bool file_matches (Dwarf_Files *files, size_t idx) 97 { 98 if (idx >= files->nfiles) 99 return false; 100 101 const char *file = files->info[idx].name; 102 if (file != lastfile) 103 { 104 size_t len = strlen (file); 105 lastfile_matches = (len >= match_file_len 106 && !memcmp (match_file, file, match_file_len) 107 && (len == match_file_len 108 || file[len - match_file_len - 1] == '/')); 109 } 110 return lastfile_matches; 111 } 112 113 /* Start with the innermost scope and move out. */ 114 for (int out = 0; out < nscopes; ++out) 115 if (INTUSE(dwarf_haschildren) (&scopes[out])) 116 { 117 if (INTUSE(dwarf_child) (&scopes[out], result) != 0) 118 return -1; 119 do 120 { 121 switch (INTUSE(dwarf_tag) (result)) 122 { 123 case DW_TAG_variable: 124 case DW_TAG_formal_parameter: 125 break; 126 127 default: 128 continue; 129 } 130 131 /* Only get here for a variable or parameter. Check the name. */ 132 Dwarf_Attribute attr_mem; 133 const char *diename = INTUSE(dwarf_formstring) 134 (INTUSE(dwarf_attr_integrate) (result, DW_AT_name, &attr_mem)); 135 if (diename != NULL && !strcmp (name, diename)) 136 { 137 /* We have a matching name. */ 138 139 if (skip_shadows > 0) 140 { 141 /* Punt this scope for the one it shadows. */ 142 --skip_shadows; 143 break; 144 } 145 146 if (match_file != NULL) 147 { 148 /* Check its decl_file. */ 149 150 Dwarf_Word i; 151 Dwarf_Files *files; 152 if (getattr (result, DW_AT_decl_file, &i) != 0 153 || getfiles (&scopes[out], &files) != 0) 154 break; 155 156 if (!file_matches (files, i)) 157 break; 158 159 if (match_lineno > 0 160 && (getattr (result, DW_AT_decl_line, &i) != 0 161 || (int) i != match_lineno)) 162 break; 163 if (match_linecol > 0 164 && (getattr (result, DW_AT_decl_column, &i) != 0 165 || (int) i != match_linecol)) 166 break; 167 } 168 169 /* We have a winner! */ 170 return out; 171 } 172 } 173 while (INTUSE(dwarf_siblingof) (result, result) == 0); 174 } 175 176 return -2; 177 } 178
