--- /dev/null Thu Jan 01 00:00:00 1970 +0000
+++ b/tools/elf4rom/libs/libelf-0.8.10/lib/checksum.c Fri Jan 15 09:07:44 2010 +0000
@@ -0,0 +1,178 @@
+/*
+checksum.c - implementation of the elf{32,64}_checksum(3) functions.
+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., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
+*/
+
+#include <private.h>
+
+#ifndef lint
+static const char rcsid[] = "@(#) $Id: checksum.c,v 1.6 2005/05/21 15:39:20 michael Exp $";
+#endif /* lint */
+
+/*
+ * Compatibility note:
+ *
+ * The algorithm used in {elf32,elf64,gelf}_checksum() does not seem to
+ * be documented. I hope I got it right. My implementation does the
+ * following:
+ *
+ * - skip sections that do not have the SHF_ALLOC flag set
+ * - skip sections of type SHT_NULL, SHT_NOBITS, SHT_DYNSYM and
+ * SHT_DYNAMIC
+ * - add all data bytes from the remaining sections, modulo 2**32
+ * - add upper and lower half of the result
+ * - subtract 0xffff if the result is > 0xffff
+ * - if any error occurs, return 0L
+ */
+
+static int
+skip_section(Elf_Scn *scn, unsigned cls) {
+ if (cls == ELFCLASS32) {
+ Elf32_Shdr *shdr = &scn->s_shdr32;
+
+ if (!(shdr->sh_flags & SHF_ALLOC)) {
+ return 1;
+ }
+ switch (shdr->sh_type) {
+ case SHT_NULL:
+ case SHT_NOBITS:
+ /* Solaris seems to ignore these, too */
+ case SHT_DYNSYM:
+ case SHT_DYNAMIC:
+ return 1;
+ }
+ }
+#if __LIBELF64
+ else if (cls == ELFCLASS64) {
+ Elf64_Shdr *shdr = &scn->s_shdr64;
+
+ if (!(shdr->sh_flags & SHF_ALLOC)) {
+ return 1;
+ }
+ switch (shdr->sh_type) {
+ case SHT_NULL:
+ case SHT_NOBITS:
+ /* Solaris seems to ignore these, too */
+ case SHT_DYNSYM:
+ case SHT_DYNAMIC:
+ return 1;
+ }
+ }
+#endif /* __LIBELF64 */
+ else {
+ seterr(ERROR_UNIMPLEMENTED);
+ }
+ return 0;
+}
+
+static long
+add_bytes(unsigned char *ptr, size_t len) {
+ long csum = 0;
+
+ while (len--) {
+ csum += *ptr++;
+ }
+ return csum;
+}
+
+static long
+_elf_csum(Elf *elf) {
+ long csum = 0;
+ Elf_Data *data;
+ Elf_Scn *scn;
+
+ if (!elf->e_ehdr && !_elf_cook(elf)) {
+ /* propagate errors from _elf_cook */
+ return 0L;
+ }
+ seterr(0);
+ for (scn = elf->e_scn_1; scn; scn = scn->s_link) {
+ if (scn->s_index == SHN_UNDEF || skip_section(scn, elf->e_class)) {
+ continue;
+ }
+ data = NULL;
+ while ((data = elf_getdata(scn, data))) {
+ if (data->d_size) {
+ if (data->d_buf == NULL) {
+ seterr(ERROR_NULLBUF);
+ return 0L;
+ }
+ csum += add_bytes(data->d_buf, data->d_size);
+ }
+ }
+ }
+ if (_elf_errno) {
+ return 0L;
+ }
+ csum = (csum & 0xffff) + ((csum >> 16) & 0xffff);
+ if (csum > 0xffff) {
+ csum -= 0xffff;
+ }
+ return csum;
+}
+
+long
+elf32_checksum(Elf *elf) {
+ if (elf) {
+ if (elf->e_kind != ELF_K_ELF) {
+ seterr(ERROR_NOTELF);
+ }
+ else if (elf->e_class != ELFCLASS32) {
+ seterr(ERROR_CLASSMISMATCH);
+ }
+ else {
+ return _elf_csum(elf);
+ }
+ }
+ return 0L;
+}
+
+#if __LIBELF64
+
+long
+elf64_checksum(Elf *elf) {
+ if (elf) {
+ if (elf->e_kind != ELF_K_ELF) {
+ seterr(ERROR_NOTELF);
+ }
+ else if (elf->e_class != ELFCLASS64) {
+ seterr(ERROR_CLASSMISMATCH);
+ }
+ else {
+ return _elf_csum(elf);
+ }
+ }
+ return 0L;
+}
+
+long
+gelf_checksum(Elf *elf) {
+ if (elf) {
+ if (elf->e_kind != ELF_K_ELF) {
+ seterr(ERROR_NOTELF);
+ }
+ else if (!valid_class(elf->e_class)) {
+ seterr(ERROR_UNKNOWN_CLASS);
+ }
+ else {
+ return _elf_csum(elf);
+ }
+ }
+ return 0L;
+}
+
+#endif /* __LIBELF64 */