ext/libelf/gelf_shdr.c

/*-
 * Copyright (c) 2006 Joseph Koshy
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 *
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 */

#include <limits.h>

#include <assert.h>
#include "gelf.h"
#include "libelf.h"

#include "_libelf.h"

Elf32_Shdr *
elf32_getshdr(Elf_Scn *s)
{
        return (_libelf_getshdr(s, ELFCLASS32));
}

Elf64_Shdr *
elf64_getshdr(Elf_Scn *s)
{
        return (_libelf_getshdr(s, ELFCLASS64));
}

GElf_Shdr *
gelf_getshdr(Elf_Scn *s, GElf_Shdr *d)
{
        int ec;
        void *sh;
        Elf32_Shdr *sh32;
        Elf64_Shdr *sh64;

        if (d == NULL) {
                LIBELF_SET_ERROR(ARGUMENT, 0);
                return (NULL);
        }

        if ((sh = _libelf_getshdr(s, ELFCLASSNONE)) == NULL)
                return (NULL);

        ec = s->s_elf->e_class;
        assert(ec == ELFCLASS32 || ec == ELFCLASS64);

        if (ec == ELFCLASS32) {
                sh32 = (Elf32_Shdr *) sh;

                d->sh_name      = sh32->sh_name;
                d->sh_type      = sh32->sh_type;
                d->sh_flags     = (Elf64_Xword) sh32->sh_flags;
                d->sh_addr      = (Elf64_Addr) sh32->sh_addr;
                d->sh_offset    = (Elf64_Off) sh32->sh_offset;
                d->sh_size      = (Elf64_Xword) sh32->sh_size;
                d->sh_link      = sh32->sh_link;
                d->sh_info      = sh32->sh_info;
                d->sh_addralign = (Elf64_Xword) sh32->sh_addralign;
                d->sh_entsize   = (Elf64_Xword) sh32->sh_entsize;
        } else {
                sh64 = (Elf64_Shdr *) sh;
                *d = *sh64;
        }

        return (d);
}

int
gelf_update_shdr(Elf_Scn *scn, GElf_Shdr *s)
{
        int ec;
        Elf *e;
        Elf32_Shdr *sh32;


        if (s == NULL || scn == NULL || (e = scn->s_elf) == NULL ||
            e->e_kind != ELF_K_ELF ||
            ((ec = e->e_class) != ELFCLASS32 && ec != ELFCLASS64)) {
                LIBELF_SET_ERROR(ARGUMENT, 0);
                return (0);
        }

        if (e->e_cmd == ELF_C_READ) {
                LIBELF_SET_ERROR(MODE, 0);
                return (0);
        }

        if (ec == ELFCLASS64) {
                scn->s_shdr.s_shdr64 = *s;
                return (1);
        }

        sh32 = &scn->s_shdr.s_shdr32;

        sh32->sh_name	 =  s->sh_name;
        sh32->sh_type	 =  s->sh_type;
        LIBELF_COPY_U32(sh32, s, sh_flags);
        LIBELF_COPY_U32(sh32, s, sh_addr);
        LIBELF_COPY_U32(sh32, s, sh_offset);
        LIBELF_COPY_U32(sh32, s, sh_size);
        sh32->sh_link	 =  s->sh_link;
        sh32->sh_info	 =  s->sh_info;
        LIBELF_COPY_U32(sh32, s, sh_addralign);
        LIBELF_COPY_U32(sh32, s, sh_entsize);

        (void) elf_flagscn(scn, ELF_C_SET, ELF_F_DIRTY);

        return (1);
}