Ulrich Drepper | b08d5a8 | 2005-07-26 05:00:05 +0000 | [diff] [blame] | 1 | /* Return the next data element from the section after possibly converting it. |
Ulrich Drepper | c07fbb3 | 2007-03-30 19:14:59 +0000 | [diff] [blame] | 2 | Copyright (C) 1998-2005, 2006, 2007 Red Hat, Inc. |
Ulrich Drepper | 361df7d | 2006-04-04 21:38:57 +0000 | [diff] [blame] | 3 | This file is part of Red Hat elfutils. |
Ulrich Drepper | b08d5a8 | 2005-07-26 05:00:05 +0000 | [diff] [blame] | 4 | Written by Ulrich Drepper <drepper@redhat.com>, 1998. |
| 5 | |
Ulrich Drepper | 361df7d | 2006-04-04 21:38:57 +0000 | [diff] [blame] | 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. |
Ulrich Drepper | b08d5a8 | 2005-07-26 05:00:05 +0000 | [diff] [blame] | 9 | |
Ulrich Drepper | 361df7d | 2006-04-04 21:38:57 +0000 | [diff] [blame] | 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. |
Ulrich Drepper | b08d5a8 | 2005-07-26 05:00:05 +0000 | [diff] [blame] | 14 | |
Ulrich Drepper | 361df7d | 2006-04-04 21:38:57 +0000 | [diff] [blame] | 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, |
Ulrich Drepper | 1e9ef50 | 2006-04-04 22:29:06 +0000 | [diff] [blame] | 17 | Inc., 51 Franklin Street, Fifth Floor, Boston MA 02110-1301 USA. |
Ulrich Drepper | 361df7d | 2006-04-04 21:38:57 +0000 | [diff] [blame] | 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>. */ |
Ulrich Drepper | b08d5a8 | 2005-07-26 05:00:05 +0000 | [diff] [blame] | 50 | |
| 51 | #ifdef HAVE_CONFIG_H |
| 52 | # include <config.h> |
| 53 | #endif |
| 54 | |
Ulrich Drepper | fbe998a | 2005-08-29 16:27:10 +0000 | [diff] [blame] | 55 | #include <errno.h> |
Ulrich Drepper | b08d5a8 | 2005-07-26 05:00:05 +0000 | [diff] [blame] | 56 | #include <stddef.h> |
| 57 | #include <string.h> |
| 58 | #include <unistd.h> |
| 59 | |
| 60 | #include "libelfP.h" |
Ulrich Drepper | fbe998a | 2005-08-29 16:27:10 +0000 | [diff] [blame] | 61 | #include <system.h> |
Ulrich Drepper | b08d5a8 | 2005-07-26 05:00:05 +0000 | [diff] [blame] | 62 | #include "common.h" |
| 63 | #include "elf-knowledge.h" |
| 64 | |
| 65 | |
Ulrich Drepper | b08d5a8 | 2005-07-26 05:00:05 +0000 | [diff] [blame] | 66 | #define TYPEIDX(Sh_Type) \ |
| 67 | (Sh_Type >= SHT_NULL && Sh_Type < SHT_NUM \ |
| 68 | ? Sh_Type \ |
Ulrich Drepper | 8ae5814 | 2006-07-12 05:22:32 +0000 | [diff] [blame] | 69 | : (Sh_Type >= SHT_GNU_HASH && Sh_Type <= SHT_HISUNW \ |
| 70 | ? SHT_NUM + Sh_Type - SHT_GNU_HASH \ |
Ulrich Drepper | b08d5a8 | 2005-07-26 05:00:05 +0000 | [diff] [blame] | 71 | : 0)) |
| 72 | |
Ulrich Drepper | c07fbb3 | 2007-03-30 19:14:59 +0000 | [diff] [blame] | 73 | /* Associate section types with libelf types. */ |
| 74 | static const Elf_Type shtype_map[EV_NUM - 1][TYPEIDX (SHT_HISUNW) + 1] = |
Ulrich Drepper | b08d5a8 | 2005-07-26 05:00:05 +0000 | [diff] [blame] | 75 | { |
Ulrich Drepper | c07fbb3 | 2007-03-30 19:14:59 +0000 | [diff] [blame] | 76 | [EV_CURRENT - 1] = |
Ulrich Drepper | b08d5a8 | 2005-07-26 05:00:05 +0000 | [diff] [blame] | 77 | { |
Ulrich Drepper | c07fbb3 | 2007-03-30 19:14:59 +0000 | [diff] [blame] | 78 | [SHT_SYMTAB] = ELF_T_SYM, |
| 79 | [SHT_RELA] = ELF_T_RELA, |
| 80 | [SHT_HASH] = ELF_T_WORD, |
| 81 | [SHT_DYNAMIC] = ELF_T_DYN, |
| 82 | [SHT_REL] = ELF_T_REL, |
| 83 | [SHT_DYNSYM] = ELF_T_SYM, |
| 84 | [SHT_INIT_ARRAY] = ELF_T_ADDR, |
| 85 | [SHT_FINI_ARRAY] = ELF_T_ADDR, |
| 86 | [SHT_PREINIT_ARRAY] = ELF_T_ADDR, |
| 87 | [SHT_GROUP] = ELF_T_WORD, |
| 88 | [SHT_SYMTAB_SHNDX] = ELF_T_WORD, |
Roland McGrath | c76f0b0 | 2007-09-27 07:31:33 +0000 | [diff] [blame] | 89 | [SHT_NOTE] = ELF_T_NHDR, |
Ulrich Drepper | c07fbb3 | 2007-03-30 19:14:59 +0000 | [diff] [blame] | 90 | [TYPEIDX (SHT_GNU_verdef)] = ELF_T_VDEF, |
| 91 | [TYPEIDX (SHT_GNU_verneed)] = ELF_T_VNEED, |
| 92 | [TYPEIDX (SHT_GNU_versym)] = ELF_T_HALF, |
| 93 | [TYPEIDX (SHT_SUNW_syminfo)] = ELF_T_SYMINFO, |
| 94 | [TYPEIDX (SHT_SUNW_move)] = ELF_T_MOVE, |
| 95 | [TYPEIDX (SHT_GNU_LIBLIST)] = ELF_T_LIB, |
| 96 | [TYPEIDX (SHT_GNU_HASH)] = ELF_T_GNUHASH, |
Ulrich Drepper | b08d5a8 | 2005-07-26 05:00:05 +0000 | [diff] [blame] | 97 | } |
Ulrich Drepper | c07fbb3 | 2007-03-30 19:14:59 +0000 | [diff] [blame] | 98 | }; |
| 99 | |
| 100 | #if !ALLOW_UNALIGNED |
| 101 | /* Associate libelf types with their internal alignment requirements. */ |
| 102 | const uint_fast8_t __libelf_type_aligns[EV_NUM - 1][ELFCLASSNUM - 1][ELF_T_NUM] = |
| 103 | { |
| 104 | # define TYPE_ALIGNS(Bits) \ |
| 105 | { \ |
| 106 | [ELF_T_ADDR] = __alignof__ (ElfW2(Bits,Addr)), \ |
| 107 | [ELF_T_HALF] = __alignof__ (ElfW2(Bits,Half)), \ |
| 108 | [ELF_T_WORD] = __alignof__ (ElfW2(Bits,Word)), \ |
| 109 | [ELF_T_SYM] = __alignof__ (ElfW2(Bits,Sym)), \ |
| 110 | [ELF_T_SYMINFO] = __alignof__ (ElfW2(Bits,Syminfo)), \ |
| 111 | [ELF_T_REL] = __alignof__ (ElfW2(Bits,Rel)), \ |
| 112 | [ELF_T_RELA] = __alignof__ (ElfW2(Bits,Rela)), \ |
| 113 | [ELF_T_DYN] = __alignof__ (ElfW2(Bits,Dyn)), \ |
| 114 | [ELF_T_VDEF] = __alignof__ (ElfW2(Bits,Verdef)), \ |
| 115 | [ELF_T_VDAUX] = __alignof__ (ElfW2(Bits,Verdaux)), \ |
| 116 | [ELF_T_VNEED] = __alignof__ (ElfW2(Bits,Verneed)), \ |
| 117 | [ELF_T_VNAUX] = __alignof__ (ElfW2(Bits,Vernaux)), \ |
| 118 | [ELF_T_MOVE] = __alignof__ (ElfW2(Bits,Move)), \ |
| 119 | [ELF_T_LIB] = __alignof__ (ElfW2(Bits,Lib)), \ |
Roland McGrath | c76f0b0 | 2007-09-27 07:31:33 +0000 | [diff] [blame] | 120 | [ELF_T_NHDR] = __alignof__ (ElfW2(Bits,Nhdr)), \ |
Ulrich Drepper | c07fbb3 | 2007-03-30 19:14:59 +0000 | [diff] [blame] | 121 | } |
| 122 | [EV_CURRENT - 1] = |
| 123 | { |
| 124 | [ELFCLASS32 - 1] = TYPE_ALIGNS (32), |
| 125 | [ELFCLASS64 - 1] = TYPE_ALIGNS (64), |
| 126 | } |
| 127 | # undef TYPE_ALIGNS |
| 128 | }; |
| 129 | #endif |
Ulrich Drepper | b08d5a8 | 2005-07-26 05:00:05 +0000 | [diff] [blame] | 130 | |
| 131 | |
| 132 | /* Convert the data in the current section. */ |
| 133 | static void |
| 134 | convert_data (Elf_Scn *scn, int version __attribute__ ((unused)), int eclass, |
Ulrich Drepper | c07fbb3 | 2007-03-30 19:14:59 +0000 | [diff] [blame] | 135 | int data, size_t size, Elf_Type type) |
Ulrich Drepper | b08d5a8 | 2005-07-26 05:00:05 +0000 | [diff] [blame] | 136 | { |
Ulrich Drepper | c07fbb3 | 2007-03-30 19:14:59 +0000 | [diff] [blame] | 137 | const size_t align = __libelf_type_align (eclass, type); |
Ulrich Drepper | b08d5a8 | 2005-07-26 05:00:05 +0000 | [diff] [blame] | 138 | |
| 139 | if (data == MY_ELFDATA) |
| 140 | { |
Ulrich Drepper | c07fbb3 | 2007-03-30 19:14:59 +0000 | [diff] [blame] | 141 | if (((((size_t) (char *) scn->rawdata_base)) & (align - 1)) == 0) |
Ulrich Drepper | b08d5a8 | 2005-07-26 05:00:05 +0000 | [diff] [blame] | 142 | /* No need to copy, we can use the raw data. */ |
| 143 | scn->data_base = scn->rawdata_base; |
| 144 | else |
| 145 | { |
| 146 | scn->data_base = (char *) malloc (size); |
| 147 | if (scn->data_base == NULL) |
| 148 | { |
| 149 | __libelf_seterrno (ELF_E_NOMEM); |
| 150 | return; |
| 151 | } |
| 152 | |
| 153 | /* The copy will be appropriately aligned for direct access. */ |
| 154 | memcpy (scn->data_base, scn->rawdata_base, size); |
| 155 | } |
| 156 | } |
| 157 | else |
| 158 | { |
| 159 | xfct_t fp; |
| 160 | |
| 161 | scn->data_base = (char *) malloc (size); |
| 162 | if (scn->data_base == NULL) |
| 163 | { |
| 164 | __libelf_seterrno (ELF_E_NOMEM); |
| 165 | return; |
| 166 | } |
| 167 | |
| 168 | /* Get the conversion function. */ |
| 169 | #if EV_NUM != 2 |
| 170 | fp = __elf_xfctstom[version - 1][__libelf_version - 1][eclass - 1][type]; |
| 171 | #else |
| 172 | fp = __elf_xfctstom[0][0][eclass - 1][type]; |
| 173 | #endif |
| 174 | |
| 175 | fp (scn->data_base, scn->rawdata_base, size, 0); |
| 176 | } |
| 177 | |
| 178 | scn->data_list.data.d.d_buf = scn->data_base; |
| 179 | scn->data_list.data.d.d_size = size; |
| 180 | scn->data_list.data.d.d_type = type; |
| 181 | scn->data_list.data.d.d_off = scn->rawdata.d.d_off; |
| 182 | scn->data_list.data.d.d_align = scn->rawdata.d.d_align; |
| 183 | scn->data_list.data.d.d_version = scn->rawdata.d.d_version; |
| 184 | |
| 185 | scn->data_list.data.s = scn; |
| 186 | } |
| 187 | |
| 188 | |
| 189 | /* Store the information for the raw data in the `rawdata' element. */ |
| 190 | int |
Ulrich Drepper | 077c65f | 2006-07-12 19:54:51 +0000 | [diff] [blame] | 191 | internal_function |
Roland McGrath | b4d6f0f | 2008-08-25 22:55:17 +0000 | [diff] [blame] | 192 | __libelf_set_rawdata_wrlock (Elf_Scn *scn) |
Ulrich Drepper | b08d5a8 | 2005-07-26 05:00:05 +0000 | [diff] [blame] | 193 | { |
| 194 | size_t offset; |
| 195 | size_t size; |
| 196 | size_t align; |
| 197 | int type; |
| 198 | Elf *elf = scn->elf; |
| 199 | |
| 200 | if (elf->class == ELFCLASS32) |
| 201 | { |
Ulrich Drepper | d56e232 | 2008-08-16 03:09:13 +0000 | [diff] [blame] | 202 | Elf32_Shdr *shdr |
Roland McGrath | b4d6f0f | 2008-08-25 22:55:17 +0000 | [diff] [blame] | 203 | = scn->shdr.e32 ?: __elf32_getshdr_wrlock (scn); |
Ulrich Drepper | b08d5a8 | 2005-07-26 05:00:05 +0000 | [diff] [blame] | 204 | |
| 205 | if (shdr == NULL) |
| 206 | /* Something went terribly wrong. */ |
| 207 | return 1; |
| 208 | |
| 209 | offset = shdr->sh_offset; |
| 210 | size = shdr->sh_size; |
| 211 | type = shdr->sh_type; |
| 212 | align = shdr->sh_addralign; |
| 213 | } |
| 214 | else |
| 215 | { |
Ulrich Drepper | d56e232 | 2008-08-16 03:09:13 +0000 | [diff] [blame] | 216 | Elf64_Shdr *shdr |
Roland McGrath | b4d6f0f | 2008-08-25 22:55:17 +0000 | [diff] [blame] | 217 | = scn->shdr.e64 ?: __elf64_getshdr_wrlock (scn); |
Ulrich Drepper | b08d5a8 | 2005-07-26 05:00:05 +0000 | [diff] [blame] | 218 | |
| 219 | if (shdr == NULL) |
| 220 | /* Something went terribly wrong. */ |
| 221 | return 1; |
| 222 | |
| 223 | offset = shdr->sh_offset; |
| 224 | size = shdr->sh_size; |
| 225 | type = shdr->sh_type; |
| 226 | align = shdr->sh_addralign; |
| 227 | } |
| 228 | |
| 229 | /* If the section has no data (for whatever reason), leave the `d_buf' |
| 230 | pointer NULL. */ |
| 231 | if (size != 0 && type != SHT_NOBITS) |
| 232 | { |
| 233 | /* First a test whether the section is valid at all. */ |
| 234 | size_t entsize; |
| 235 | |
| 236 | if (type == SHT_HASH) |
| 237 | { |
| 238 | GElf_Ehdr ehdr_mem; |
Roland McGrath | b4d6f0f | 2008-08-25 22:55:17 +0000 | [diff] [blame] | 239 | GElf_Ehdr *ehdr = __gelf_getehdr_rdlock (elf, &ehdr_mem); |
Ulrich Drepper | d56e232 | 2008-08-16 03:09:13 +0000 | [diff] [blame] | 240 | entsize = SH_ENTSIZE_HASH (ehdr); |
Ulrich Drepper | b08d5a8 | 2005-07-26 05:00:05 +0000 | [diff] [blame] | 241 | } |
| 242 | else |
| 243 | { |
Ulrich Drepper | c07fbb3 | 2007-03-30 19:14:59 +0000 | [diff] [blame] | 244 | Elf_Type t = shtype_map[LIBELF_EV_IDX][TYPEIDX (type)]; |
Roland McGrath | c76f0b0 | 2007-09-27 07:31:33 +0000 | [diff] [blame] | 245 | if (t == ELF_T_VDEF || t == ELF_T_NHDR |
Ulrich Drepper | c07fbb3 | 2007-03-30 19:14:59 +0000 | [diff] [blame] | 246 | || (t == ELF_T_GNUHASH && elf->class == ELFCLASS64)) |
| 247 | entsize = 1; |
| 248 | else |
| 249 | entsize = __libelf_type_sizes[LIBELF_EV_IDX][elf->class - 1][t]; |
Ulrich Drepper | b08d5a8 | 2005-07-26 05:00:05 +0000 | [diff] [blame] | 250 | } |
| 251 | |
| 252 | /* We assume it is an array of bytes if it is none of the structured |
| 253 | sections we know of. */ |
| 254 | if (entsize == 0) |
| 255 | entsize = 1; |
| 256 | |
Ulrich Drepper | fbe998a | 2005-08-29 16:27:10 +0000 | [diff] [blame] | 257 | if (unlikely (size % entsize != 0)) |
Ulrich Drepper | b08d5a8 | 2005-07-26 05:00:05 +0000 | [diff] [blame] | 258 | { |
| 259 | __libelf_seterrno (ELF_E_INVALID_DATA); |
| 260 | return 1; |
| 261 | } |
| 262 | |
| 263 | /* We can use the mapped or loaded data if available. */ |
| 264 | if (elf->map_address != NULL) |
| 265 | { |
| 266 | /* First see whether the information in the section header is |
| 267 | valid and it does not ask for too much. */ |
Ulrich Drepper | fbe998a | 2005-08-29 16:27:10 +0000 | [diff] [blame] | 268 | if (unlikely (offset + size > elf->maximum_size)) |
Ulrich Drepper | b08d5a8 | 2005-07-26 05:00:05 +0000 | [diff] [blame] | 269 | { |
| 270 | /* Something is wrong. */ |
| 271 | __libelf_seterrno (ELF_E_INVALID_SECTION_HEADER); |
| 272 | return 1; |
| 273 | } |
| 274 | |
| 275 | scn->rawdata_base = scn->rawdata.d.d_buf |
| 276 | = (char *) elf->map_address + elf->start_offset + offset; |
| 277 | } |
Ulrich Drepper | fbe998a | 2005-08-29 16:27:10 +0000 | [diff] [blame] | 278 | else if (likely (elf->fildes != -1)) |
Ulrich Drepper | b08d5a8 | 2005-07-26 05:00:05 +0000 | [diff] [blame] | 279 | { |
| 280 | /* We have to read the data from the file. Allocate the needed |
| 281 | memory. */ |
| 282 | scn->rawdata_base = scn->rawdata.d.d_buf |
| 283 | = (char *) malloc (size); |
| 284 | if (scn->rawdata.d.d_buf == NULL) |
| 285 | { |
| 286 | __libelf_seterrno (ELF_E_NOMEM); |
| 287 | return 1; |
| 288 | } |
| 289 | |
Ulrich Drepper | fbe998a | 2005-08-29 16:27:10 +0000 | [diff] [blame] | 290 | ssize_t n = pread_retry (elf->fildes, scn->rawdata.d.d_buf, size, |
| 291 | elf->start_offset + offset); |
| 292 | if (unlikely ((size_t) n != size)) |
Ulrich Drepper | b08d5a8 | 2005-07-26 05:00:05 +0000 | [diff] [blame] | 293 | { |
| 294 | /* Cannot read the data. */ |
| 295 | free (scn->rawdata.d.d_buf); |
| 296 | scn->rawdata_base = scn->rawdata.d.d_buf = NULL; |
| 297 | __libelf_seterrno (ELF_E_READ_ERROR); |
| 298 | return 1; |
| 299 | } |
| 300 | } |
| 301 | else |
| 302 | { |
| 303 | /* The file descriptor is already closed, we cannot get the data |
| 304 | anymore. */ |
| 305 | __libelf_seterrno (ELF_E_FD_DISABLED); |
| 306 | return 1; |
| 307 | } |
| 308 | } |
| 309 | |
| 310 | scn->rawdata.d.d_size = size; |
| 311 | /* Some broken ELF ABI for 64-bit machines use the wrong hash table |
| 312 | entry size. See elf-knowledge.h for more information. */ |
| 313 | if (type == SHT_HASH && elf->class == ELFCLASS64) |
| 314 | { |
| 315 | GElf_Ehdr ehdr_mem; |
Roland McGrath | b4d6f0f | 2008-08-25 22:55:17 +0000 | [diff] [blame] | 316 | GElf_Ehdr *ehdr = __gelf_getehdr_rdlock (elf, &ehdr_mem); |
Ulrich Drepper | b08d5a8 | 2005-07-26 05:00:05 +0000 | [diff] [blame] | 317 | scn->rawdata.d.d_type |
Ulrich Drepper | d56e232 | 2008-08-16 03:09:13 +0000 | [diff] [blame] | 318 | = (SH_ENTSIZE_HASH (ehdr) == 4 ? ELF_T_WORD : ELF_T_XWORD); |
Ulrich Drepper | b08d5a8 | 2005-07-26 05:00:05 +0000 | [diff] [blame] | 319 | } |
| 320 | else |
Ulrich Drepper | c07fbb3 | 2007-03-30 19:14:59 +0000 | [diff] [blame] | 321 | scn->rawdata.d.d_type = shtype_map[LIBELF_EV_IDX][TYPEIDX (type)]; |
Ulrich Drepper | b08d5a8 | 2005-07-26 05:00:05 +0000 | [diff] [blame] | 322 | scn->rawdata.d.d_off = 0; |
| 323 | scn->rawdata.d.d_align = align; |
| 324 | if (elf->class == ELFCLASS32 |
| 325 | || (offsetof (struct Elf, state.elf32.ehdr) |
| 326 | == offsetof (struct Elf, state.elf64.ehdr))) |
| 327 | scn->rawdata.d.d_version = |
| 328 | elf->state.elf32.ehdr->e_ident[EI_VERSION]; |
| 329 | else |
| 330 | scn->rawdata.d.d_version = |
| 331 | elf->state.elf64.ehdr->e_ident[EI_VERSION]; |
| 332 | |
| 333 | scn->rawdata.s = scn; |
| 334 | |
| 335 | scn->data_read = 1; |
| 336 | |
| 337 | /* We actually read data from the file. At least we tried. */ |
| 338 | scn->flags |= ELF_F_FILEDATA; |
| 339 | |
| 340 | return 0; |
| 341 | } |
| 342 | |
Roland McGrath | b4d6f0f | 2008-08-25 22:55:17 +0000 | [diff] [blame] | 343 | int |
| 344 | internal_function |
| 345 | __libelf_set_rawdata (Elf_Scn *scn) |
| 346 | { |
| 347 | int result; |
| 348 | |
| 349 | if (scn == NULL) |
| 350 | return 1; |
| 351 | |
| 352 | rwlock_wrlock (scn->elf->lock); |
| 353 | result = __libelf_set_rawdata_wrlock (scn); |
| 354 | rwlock_unlock (scn->elf->lock); |
| 355 | |
| 356 | return result; |
| 357 | } |
Ulrich Drepper | b08d5a8 | 2005-07-26 05:00:05 +0000 | [diff] [blame] | 358 | |
| 359 | Elf_Data * |
Roland McGrath | b4d6f0f | 2008-08-25 22:55:17 +0000 | [diff] [blame] | 360 | internal_function |
| 361 | __elf_getdata_rdlock (scn, data) |
Ulrich Drepper | b08d5a8 | 2005-07-26 05:00:05 +0000 | [diff] [blame] | 362 | Elf_Scn *scn; |
| 363 | Elf_Data *data; |
| 364 | { |
| 365 | Elf_Data *result = NULL; |
| 366 | Elf *elf; |
Ulrich Drepper | 02f6645 | 2008-12-04 05:58:16 +0000 | [diff] [blame] | 367 | int locked = 0; |
Ulrich Drepper | b08d5a8 | 2005-07-26 05:00:05 +0000 | [diff] [blame] | 368 | |
| 369 | if (scn == NULL) |
| 370 | return NULL; |
| 371 | |
| 372 | if (unlikely (scn->elf->kind != ELF_K_ELF)) |
| 373 | { |
| 374 | __libelf_seterrno (ELF_E_INVALID_HANDLE); |
| 375 | return NULL; |
| 376 | } |
| 377 | |
| 378 | /* We will need this multiple times later on. */ |
| 379 | elf = scn->elf; |
| 380 | |
Ulrich Drepper | b08d5a8 | 2005-07-26 05:00:05 +0000 | [diff] [blame] | 381 | /* If `data' is not NULL this means we are not addressing the initial |
| 382 | data in the file. But this also means this data is already read |
| 383 | (since otherwise it is not possible to have a valid `data' pointer) |
| 384 | and all the data structures are initialized as well. In this case |
| 385 | we can simply walk the list of data records. */ |
| 386 | if (data != NULL) |
| 387 | { |
| 388 | Elf_Data_List *runp; |
| 389 | |
| 390 | /* It is not possible that if DATA is not NULL the first entry is |
| 391 | returned. But this also means that there must be a first data |
| 392 | entry. */ |
| 393 | if (scn->data_list_rear == NULL |
| 394 | /* The section the reference data is for must match the section |
| 395 | parameter. */ |
| 396 | || unlikely (((Elf_Data_Scn *) data)->s != scn)) |
| 397 | { |
| 398 | __libelf_seterrno (ELF_E_DATA_MISMATCH); |
| 399 | goto out; |
| 400 | } |
| 401 | |
| 402 | /* We start searching with the first entry. */ |
| 403 | runp = &scn->data_list; |
| 404 | |
| 405 | while (1) |
| 406 | { |
| 407 | /* If `data' does not match any known record punt. */ |
| 408 | if (runp == NULL) |
| 409 | { |
| 410 | __libelf_seterrno (ELF_E_DATA_MISMATCH); |
| 411 | goto out; |
| 412 | } |
| 413 | |
| 414 | if (&runp->data.d == data) |
| 415 | /* Found the entry. */ |
| 416 | break; |
| 417 | |
| 418 | runp = runp->next; |
| 419 | } |
| 420 | |
| 421 | /* Return the data for the next data record. */ |
| 422 | result = runp->next ? &runp->next->data.d : NULL; |
| 423 | goto out; |
| 424 | } |
| 425 | |
| 426 | /* If the data for this section was not yet initialized do it now. */ |
| 427 | if (scn->data_read == 0) |
| 428 | { |
| 429 | /* We cannot acquire a write lock while we are holding a read |
| 430 | lock. Therefore give up the read lock and then get the write |
| 431 | lock. But this means that the data could meanwhile be |
| 432 | modified, therefore start the tests again. */ |
Roland McGrath | b4d6f0f | 2008-08-25 22:55:17 +0000 | [diff] [blame] | 433 | rwlock_unlock (elf->lock); |
| 434 | rwlock_wrlock (elf->lock); |
Ulrich Drepper | 02f6645 | 2008-12-04 05:58:16 +0000 | [diff] [blame] | 435 | locked = 1; |
Ulrich Drepper | b08d5a8 | 2005-07-26 05:00:05 +0000 | [diff] [blame] | 436 | |
| 437 | /* Read the data from the file. There is always a file (or |
| 438 | memory region) associated with this descriptor since |
| 439 | otherwise the `data_read' flag would be set. */ |
Roland McGrath | b4d6f0f | 2008-08-25 22:55:17 +0000 | [diff] [blame] | 440 | if (scn->data_read == 0 && __libelf_set_rawdata_wrlock (scn) != 0) |
Ulrich Drepper | b08d5a8 | 2005-07-26 05:00:05 +0000 | [diff] [blame] | 441 | /* Something went wrong. The error value is already set. */ |
| 442 | goto out; |
| 443 | } |
| 444 | |
| 445 | /* At this point we know the raw data is available. But it might be |
| 446 | empty in case the section has size zero (for whatever reason). |
| 447 | Now create the converted data in case this is necessary. */ |
| 448 | if (scn->data_list_rear == NULL) |
| 449 | { |
| 450 | if (scn->rawdata.d.d_buf != NULL && scn->rawdata.d.d_size > 0) |
Ulrich Drepper | 02f6645 | 2008-12-04 05:58:16 +0000 | [diff] [blame] | 451 | { |
| 452 | if (!locked) |
| 453 | { |
| 454 | rwlock_unlock (elf->lock); |
| 455 | rwlock_wrlock (elf->lock); |
| 456 | if (scn->data_list_rear != NULL) |
| 457 | goto pass; |
| 458 | } |
| 459 | |
| 460 | /* Convert according to the version and the type. */ |
| 461 | convert_data (scn, __libelf_version, elf->class, |
| 462 | (elf->class == ELFCLASS32 |
| 463 | || (offsetof (struct Elf, state.elf32.ehdr) |
| 464 | == offsetof (struct Elf, state.elf64.ehdr)) |
| 465 | ? elf->state.elf32.ehdr->e_ident[EI_DATA] |
| 466 | : elf->state.elf64.ehdr->e_ident[EI_DATA]), |
| 467 | scn->rawdata.d.d_size, scn->rawdata.d.d_type); |
| 468 | } |
Ulrich Drepper | b08d5a8 | 2005-07-26 05:00:05 +0000 | [diff] [blame] | 469 | else |
Petr Machata | d7b12c6 | 2010-04-06 14:17:41 +0200 | [diff] [blame] | 470 | { |
| 471 | /* This is an empty or NOBITS section. There is no buffer but |
| 472 | the size information etc is important. */ |
| 473 | scn->data_list.data.d = scn->rawdata.d; |
| 474 | scn->data_list.data.s = scn; |
| 475 | } |
Ulrich Drepper | b08d5a8 | 2005-07-26 05:00:05 +0000 | [diff] [blame] | 476 | |
| 477 | scn->data_list_rear = &scn->data_list; |
| 478 | } |
| 479 | |
| 480 | /* If no data is present we cannot return any. */ |
| 481 | if (scn->data_list_rear != NULL) |
Ulrich Drepper | 02f6645 | 2008-12-04 05:58:16 +0000 | [diff] [blame] | 482 | pass: |
Ulrich Drepper | b08d5a8 | 2005-07-26 05:00:05 +0000 | [diff] [blame] | 483 | /* Return the first data element in the list. */ |
| 484 | result = &scn->data_list.data.d; |
| 485 | |
| 486 | out: |
Ulrich Drepper | b08d5a8 | 2005-07-26 05:00:05 +0000 | [diff] [blame] | 487 | return result; |
| 488 | } |
Ulrich Drepper | d56e232 | 2008-08-16 03:09:13 +0000 | [diff] [blame] | 489 | |
| 490 | Elf_Data * |
| 491 | elf_getdata (scn, data) |
| 492 | Elf_Scn *scn; |
| 493 | Elf_Data *data; |
| 494 | { |
Roland McGrath | b4d6f0f | 2008-08-25 22:55:17 +0000 | [diff] [blame] | 495 | Elf_Data *result; |
| 496 | |
Ulrich Drepper | d56e232 | 2008-08-16 03:09:13 +0000 | [diff] [blame] | 497 | if (scn == NULL) |
| 498 | return NULL; |
| 499 | |
Roland McGrath | b4d6f0f | 2008-08-25 22:55:17 +0000 | [diff] [blame] | 500 | rwlock_rdlock (scn->elf->lock); |
| 501 | result = __elf_getdata_rdlock (scn, data); |
| 502 | rwlock_unlock (scn->elf->lock); |
| 503 | |
| 504 | return result; |
Ulrich Drepper | d56e232 | 2008-08-16 03:09:13 +0000 | [diff] [blame] | 505 | } |
Roland McGrath | b4d6f0f | 2008-08-25 22:55:17 +0000 | [diff] [blame] | 506 | INTDEF(elf_getdata) |