rpm/libelf/lib/gelfehdr.c

/*
gelfehdr.c - gelf_* translation functions.
Copyright (C) 2000 - 2001 Michael Riepe <michael@stud.uni-hannover.de>

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>

#if __LIBELF64

#ifndef lint
static const char rcsid[] = "@(#) Id: gelfehdr.c,v 1.3 2001/10/07 19:33:03 michael Exp ";
#endif /* lint */

#define check_and_copy(type, d, s, name, eret)		\
    do {						\
	if (sizeof((d)->name) < sizeof((s)->name)	\
	 && (type)(s)->name != (s)->name) {		\
	    seterr(ERROR_BADVALUE);			\
	    return (eret);				\
	}						\
	(d)->name = (type)(s)->name;			\
    } while (0)

GElf_Ehdr*
gelf_getehdr(Elf *elf, GElf_Ehdr *dst) {
    GElf_Ehdr buf;
    char *tmp;

    if (!elf) {
	return NULL;
    }
    elf_assert(elf->e_magic == ELF_MAGIC);
    tmp = _elf_getehdr(elf, elf->e_class);
    if (!tmp) {
	return NULL;
    }
    if (!dst) {
	dst = &buf;
    }
    if (elf->e_class == ELFCLASS64) {
/*@-boundswrite@*/ /* structure assignment */
	*dst = *(Elf64_Ehdr*)tmp;
/*@=boundswrite@*/
    }
    else if (elf->e_class == ELFCLASS32) {
	Elf32_Ehdr *src = (Elf32_Ehdr*)tmp;

/*@-boundsread@*/
	memcpy(dst->e_ident, src->e_ident, EI_NIDENT);
/*@=boundsread@*/
	check_and_copy(GElf_Half, dst, src, e_type,      NULL);
	check_and_copy(GElf_Half, dst, src, e_machine,   NULL);
	check_and_copy(GElf_Word, dst, src, e_version,   NULL);
	check_and_copy(GElf_Addr, dst, src, e_entry,     NULL);
	check_and_copy(GElf_Off,  dst, src, e_phoff,     NULL);
	check_and_copy(GElf_Off,  dst, src, e_shoff,     NULL);
	check_and_copy(GElf_Word, dst, src, e_flags,     NULL);
	check_and_copy(GElf_Half, dst, src, e_ehsize,    NULL);
	check_and_copy(GElf_Half, dst, src, e_phentsize, NULL);
	check_and_copy(GElf_Half, dst, src, e_phnum,     NULL);
	check_and_copy(GElf_Half, dst, src, e_shentsize, NULL);
	check_and_copy(GElf_Half, dst, src, e_shnum,     NULL);
	check_and_copy(GElf_Half, dst, src, e_shstrndx,  NULL);
    }
    else if (valid_class(elf->e_class)) {
	seterr(ERROR_UNIMPLEMENTED);
	return NULL;
    }
    else {
	seterr(ERROR_UNKNOWN_CLASS);
	return NULL;
    }
    if (dst == &buf) {
	dst = (GElf_Ehdr*)malloc(sizeof(GElf_Ehdr));
	if (!dst) {
	    seterr(ERROR_MEM_EHDR);
	    return NULL;
	}
/*@-boundswrite@*/ /* structure assignment */
	*dst = buf;
/*@=boundswrite@*/
    }
    return dst;
}

int
gelf_update_ehdr(Elf *elf, GElf_Ehdr *src) {
    char *tmp;

    if (!elf || !src) {
	return 0;
    }
    elf_assert(elf->e_magic == ELF_MAGIC);
    tmp = _elf_getehdr(elf, elf->e_class);
    if (!tmp) {
	return 0;
    }
    if (elf->e_class == ELFCLASS64) {
/*@-boundswrite@*/ /* structure assignment */
	*(Elf64_Ehdr*)tmp = *src;
/*@=boundswrite@*/
    }
    else if (elf->e_class == ELFCLASS32) {
	Elf32_Ehdr *dst = (Elf32_Ehdr*)tmp;

/*@-boundsread@*/
	memcpy(dst->e_ident, src->e_ident, EI_NIDENT);
/*@=boundsread@*/
	check_and_copy(Elf32_Half, dst, src, e_type,      0);
	check_and_copy(Elf32_Half, dst, src, e_machine,   0);
	check_and_copy(Elf32_Word, dst, src, e_version,   0);
	check_and_copy(Elf32_Addr, dst, src, e_entry,     0);
	check_and_copy(Elf32_Off,  dst, src, e_phoff,     0);
	check_and_copy(Elf32_Off,  dst, src, e_shoff,     0);
	check_and_copy(Elf32_Word, dst, src, e_flags,     0);
	check_and_copy(Elf32_Half, dst, src, e_ehsize,    0);
	check_and_copy(Elf32_Half, dst, src, e_phentsize, 0);
	check_and_copy(Elf32_Half, dst, src, e_phnum,     0);
	check_and_copy(Elf32_Half, dst, src, e_shentsize, 0);
	check_and_copy(Elf32_Half, dst, src, e_shnum,     0);
	check_and_copy(Elf32_Half, dst, src, e_shstrndx,  0);
    }
    else if (valid_class(elf->e_class)) {
	seterr(ERROR_UNIMPLEMENTED);
	return 0;
    }
    else {
	seterr(ERROR_UNKNOWN_CLASS);
	return 0;
    }
    return 1;
}

#endif /* __LIBELF64 */