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authorIgor Pashev <pashev.igor@gmail.com>2012-09-04 18:09:07 +0400
committerIgor Pashev <pashev.igor@gmail.com>2012-09-04 18:09:07 +0400
commitea8b1f90d46279d7814a0c7f6b6742d3fab034f7 (patch)
treed626f0ab0d0016423d9ac76473ec928c231b91a5 /lib/getdata.c
downloadlibelf-upstream.tar.gz
Imported Upstream version 0.8.13upstream
Diffstat (limited to 'lib/getdata.c')
-rw-r--r--lib/getdata.c157
1 files changed, 157 insertions, 0 deletions
diff --git a/lib/getdata.c b/lib/getdata.c
new file mode 100644
index 0000000..a65b7aa
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+++ b/lib/getdata.c
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+/*
+getdata.c - implementation of the elf_getdata(3) function.
+Copyright (C) 1995 - 2001 Michael Riepe
+
+This library is free software; you can redistribute it and/or
+modify it under the terms of the GNU Library General Public
+License as published by the Free Software Foundation; either
+version 2 of the License, or (at your option) any later version.
+
+This library is distributed in the hope that it will be useful,
+but WITHOUT ANY WARRANTY; without even the implied warranty of
+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+Library General Public License for more details.
+
+You should have received a copy of the GNU Library General Public
+License along with this library; if not, write to the Free Software
+Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA
+*/
+
+#include <private.h>
+
+#ifndef lint
+static const char rcsid[] = "@(#) $Id: getdata.c,v 1.13 2008/05/23 08:15:34 michael Exp $";
+#endif /* lint */
+
+static Elf_Data*
+_elf_cook_scn(Elf *elf, Elf_Scn *scn, Scn_Data *sd) {
+ Elf_Data dst;
+ Elf_Data src;
+ int flag = 0;
+ size_t dlen;
+
+ elf_assert(elf->e_data);
+
+ /*
+ * Prepare source
+ */
+ src = sd->sd_data;
+ src.d_version = elf->e_version;
+ if (elf->e_rawdata) {
+ src.d_buf = elf->e_rawdata + scn->s_offset;
+ }
+ else {
+ src.d_buf = elf->e_data + scn->s_offset;
+ }
+
+ /*
+ * Prepare destination (needs prepared source!)
+ */
+ dst = sd->sd_data;
+ if (elf->e_class == ELFCLASS32) {
+ dlen = _elf32_xltsize(&src, dst.d_version, elf->e_encoding, 0);
+ }
+#if __LIBELF64
+ else if (elf->e_class == ELFCLASS64) {
+ dlen = _elf64_xltsize(&src, dst.d_version, elf->e_encoding, 0);
+ }
+#endif /* __LIBELF64 */
+ else {
+ elf_assert(valid_class(elf->e_class));
+ seterr(ERROR_UNIMPLEMENTED);
+ return NULL;
+ }
+ if (dlen == (size_t)-1) {
+ return NULL;
+ }
+ dst.d_size = dlen;
+ if (elf->e_rawdata != elf->e_data && dst.d_size <= src.d_size) {
+ dst.d_buf = elf->e_data + scn->s_offset;
+ }
+ else if (!(dst.d_buf = malloc(dst.d_size))) {
+ seterr(ERROR_MEM_SCNDATA);
+ return NULL;
+ }
+ else {
+ flag = 1;
+ }
+
+ /*
+ * Translate data
+ */
+ if (_elf_xlatetom(elf, &dst, &src)) {
+ sd->sd_memdata = (char*)dst.d_buf;
+ sd->sd_data = dst;
+ if (!(sd->sd_free_data = flag)) {
+ elf->e_cooked = 1;
+ }
+ return &sd->sd_data;
+ }
+
+ if (flag) {
+ free(dst.d_buf);
+ }
+ return NULL;
+}
+
+Elf_Data*
+elf_getdata(Elf_Scn *scn, Elf_Data *data) {
+ Scn_Data *sd;
+ Elf *elf;
+
+ if (!scn) {
+ return NULL;
+ }
+ elf_assert(scn->s_magic == SCN_MAGIC);
+ if (scn->s_index == SHN_UNDEF) {
+ seterr(ERROR_NULLSCN);
+ }
+ else if (data) {
+ for (sd = scn->s_data_1; sd; sd = sd->sd_link) {
+ elf_assert(sd->sd_magic == DATA_MAGIC);
+ elf_assert(sd->sd_scn == scn);
+ if (data == &sd->sd_data) {
+ /*
+ * sd_link allocated by elf_newdata().
+ */
+ return &sd->sd_link->sd_data;
+ }
+ }
+ seterr(ERROR_SCNDATAMISMATCH);
+ }
+ else if ((sd = scn->s_data_1)) {
+ elf_assert(sd->sd_magic == DATA_MAGIC);
+ elf_assert(sd->sd_scn == scn);
+ elf = scn->s_elf;
+ elf_assert(elf);
+ elf_assert(elf->e_magic == ELF_MAGIC);
+ if (sd->sd_freeme) {
+ /* allocated by elf_newdata() */
+ return &sd->sd_data;
+ }
+ else if (scn->s_type == SHT_NULL) {
+ seterr(ERROR_NULLSCN);
+ }
+ else if (sd->sd_memdata) {
+ /* already cooked */
+ return &sd->sd_data;
+ }
+ else if (scn->s_offset < 0 || scn->s_offset > elf->e_size) {
+ seterr(ERROR_OUTSIDE);
+ }
+ else if (scn->s_type == SHT_NOBITS || !scn->s_size) {
+ /* no data to read */
+ return &sd->sd_data;
+ }
+ else if (scn->s_offset + scn->s_size > elf->e_size) {
+ seterr(ERROR_TRUNC_SCN);
+ }
+ else if (valid_class(elf->e_class)) {
+ return _elf_cook_scn(elf, scn, sd);
+ }
+ else {
+ seterr(ERROR_UNKNOWN_CLASS);
+ }
+ }
+ return NULL;
+}