1 /* Get symbol information from symbol table at the given index. 2 Copyright (C) 1999, 2000, 2001, 2002 Red Hat, Inc. 3 This file is part of Red Hat elfutils. 4 Written by Ulrich Drepper <drepper (at) redhat.com>, 1999. 5 6 Red Hat elfutils is free software; you can redistribute it and/or modify 7 it under the terms of the GNU General Public License as published by the 8 Free Software Foundation; version 2 of the License. 9 10 Red Hat elfutils is distributed in the hope that it will be useful, but 11 WITHOUT ANY WARRANTY; without even the implied warranty of 12 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 13 General Public License for more details. 14 15 You should have received a copy of the GNU General Public License along 16 with Red Hat elfutils; if not, write to the Free Software Foundation, 17 Inc., 51 Franklin Street, Fifth Floor, Boston MA 02110-1301 USA. 18 19 In addition, as a special exception, Red Hat, Inc. gives You the 20 additional right to link the code of Red Hat elfutils with code licensed 21 under any Open Source Initiative certified open source license 22 (http://www.opensource.org/licenses/index.php) which requires the 23 distribution of source code with any binary distribution and to 24 distribute linked combinations of the two. Non-GPL Code permitted under 25 this exception must only link to the code of Red Hat elfutils through 26 those well defined interfaces identified in the file named EXCEPTION 27 found in the source code files (the "Approved Interfaces"). The files 28 of Non-GPL Code may instantiate templates or use macros or inline 29 functions from the Approved Interfaces without causing the resulting 30 work to be covered by the GNU General Public License. Only Red Hat, 31 Inc. may make changes or additions to the list of Approved Interfaces. 32 Red Hat's grant of this exception is conditioned upon your not adding 33 any new exceptions. If you wish to add a new Approved Interface or 34 exception, please contact Red Hat. You must obey the GNU General Public 35 License in all respects for all of the Red Hat elfutils code and other 36 code used in conjunction with Red Hat elfutils except the Non-GPL Code 37 covered by this exception. If you modify this file, you may extend this 38 exception to your version of the file, but you are not obligated to do 39 so. If you do not wish to provide this exception without modification, 40 you must delete this exception statement from your version and license 41 this file solely under the GPL without exception. 42 43 Red Hat elfutils is an included package of the Open Invention Network. 44 An included package of the Open Invention Network is a package for which 45 Open Invention Network licensees cross-license their patents. No patent 46 license is granted, either expressly or impliedly, by designation as an 47 included package. Should you wish to participate in the Open Invention 48 Network licensing program, please visit www.openinventionnetwork.com 49 <http://www.openinventionnetwork.com>. */ 50 51 #ifdef HAVE_CONFIG_H 52 # include <config.h> 53 #endif 54 55 #include <assert.h> 56 #include <gelf.h> 57 #include <string.h> 58 59 #include "libelfP.h" 60 61 62 GElf_Sym * 63 gelf_getsym (data, ndx, dst) 64 Elf_Data *data; 65 int ndx; 66 GElf_Sym *dst; 67 { 68 Elf_Data_Scn *data_scn = (Elf_Data_Scn *) data; 69 GElf_Sym *result = NULL; 70 71 if (data == NULL) 72 return NULL; 73 74 if (unlikely (data->d_type != ELF_T_SYM)) 75 { 76 __libelf_seterrno (ELF_E_INVALID_HANDLE); 77 return NULL; 78 } 79 80 rwlock_rdlock (data_scn->s->elf->lock); 81 82 /* This is the one place where we have to take advantage of the fact 83 that an `Elf_Data' pointer is also a pointer to `Elf_Data_Scn'. 84 The interface is broken so that it requires this hack. */ 85 if (data_scn->s->elf->class == ELFCLASS32) 86 { 87 Elf32_Sym *src; 88 89 /* Here it gets a bit more complicated. The format of the symbol 90 table entries has to be adopted. The user better has provided 91 a buffer where we can store the information. While copying the 92 data we are converting the format. */ 93 if (unlikely ((ndx + 1) * sizeof (Elf32_Sym) > data->d_size)) 94 { 95 __libelf_seterrno (ELF_E_INVALID_INDEX); 96 goto out; 97 } 98 99 src = &((Elf32_Sym *) data->d_buf)[ndx]; 100 101 /* This might look like a simple copy operation but it's 102 not. There are zero- and sign-extensions going on. */ 103 #define COPY(name) \ 104 dst->name = src->name 105 COPY (st_name); 106 /* Please note that we can simply copy the `st_info' element since 107 the definitions of ELFxx_ST_BIND and ELFxx_ST_TYPE are the same 108 for the 64 bit variant. */ 109 COPY (st_info); 110 COPY (st_other); 111 COPY (st_shndx); 112 COPY (st_value); 113 COPY (st_size); 114 } 115 else 116 { 117 /* If this is a 64 bit object it's easy. */ 118 assert (sizeof (GElf_Sym) == sizeof (Elf64_Sym)); 119 120 /* The data is already in the correct form. Just make sure the 121 index is OK. */ 122 if (unlikely ((ndx + 1) * sizeof (GElf_Sym) > data->d_size)) 123 { 124 __libelf_seterrno (ELF_E_INVALID_INDEX); 125 goto out; 126 } 127 128 *dst = ((GElf_Sym *) data->d_buf)[ndx]; 129 } 130 131 result = dst; 132 133 out: 134 rwlock_unlock (data_scn->s->elf->lock); 135 136 return result; 137 } 138 INTDEF(gelf_getsym) 139
