/*      $NetBSD: libelf_extended.c,v 1.5 2024/03/03 17:37:34 christos Exp $     */

/*-
* Copyright (c) 2006,2008 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.
*/

#if HAVE_NBTOOL_CONFIG_H
# include "nbtool_config.h"
#endif

#include <sys/cdefs.h>

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

#include "_libelf.h"

__RCSID("$NetBSD: libelf_extended.c,v 1.5 2024/03/03 17:37:34 christos Exp $");
ELFTC_VCSID("Id: libelf_extended.c 3977 2022-05-01 06:45:34Z jkoshy");

/*
* Retrieve section #0, allocating a new section if needed.
*/
static Elf_Scn *
_libelf_getscn0(Elf *e)
{
       Elf_Scn *s;

       if ((s = STAILQ_FIRST(&e->e_u.e_elf.e_scn)) != NULL)
               return (s);

       return (_libelf_allocate_scn(e, (size_t) SHN_UNDEF));
}

int
_libelf_setshnum(Elf *e, void *eh, int ec, size_t shnum)
{
       Elf_Scn *scn;

       if (shnum >= SHN_LORESERVE) {
               if ((scn = _libelf_getscn0(e)) == NULL)
                       return (0);

               assert(scn->s_ndx == SHN_UNDEF);

               if (ec == ELFCLASS32)
                       scn->s_shdr.s_shdr32.sh_size = (Elf32_Word) shnum;
               else
                       scn->s_shdr.s_shdr64.sh_size = shnum;

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

               shnum = 0;
       }

       if (ec == ELFCLASS32)
               ((Elf32_Ehdr *) eh)->e_shnum = shnum & 0xFFFFU;
       else
               ((Elf64_Ehdr *) eh)->e_shnum = shnum & 0xFFFFU;


       return (1);
}

int
_libelf_setshstrndx(Elf *e, void *eh, int ec, size_t shstrndx)
{
       Elf_Scn *scn;

       if (shstrndx >= SHN_LORESERVE) {
               if ((scn = _libelf_getscn0(e)) == NULL)
                       return (0);

               assert(scn->s_ndx == SHN_UNDEF);

               if (ec == ELFCLASS32)
                       scn->s_shdr.s_shdr32.sh_link = (Elf32_Word) shstrndx;
               else
                       scn->s_shdr.s_shdr64.sh_link = (Elf64_Word) shstrndx;

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

               shstrndx = SHN_XINDEX;
       }

       if (ec == ELFCLASS32)
               ((Elf32_Ehdr *) eh)->e_shstrndx = shstrndx & 0xFFFFU;
       else
               ((Elf64_Ehdr *) eh)->e_shstrndx = shstrndx & 0xFFFFU;

       return (1);
}

int
_libelf_setphnum(Elf *e, void *eh, int ec, size_t phnum)
{
       Elf_Scn *scn;

       if (phnum >= PN_XNUM) {
               if ((scn = _libelf_getscn0(e)) == NULL)
                       return (0);

               assert(scn->s_ndx == SHN_UNDEF);

               if (ec == ELFCLASS32)
                       scn->s_shdr.s_shdr32.sh_info = (Elf32_Word) phnum;
               else
                       scn->s_shdr.s_shdr64.sh_info = (Elf64_Word) phnum;

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

               phnum = PN_XNUM;
       }

       if (ec == ELFCLASS32)
               ((Elf32_Ehdr *) eh)->e_phnum = phnum & 0xFFFFU;
       else
               ((Elf64_Ehdr *) eh)->e_phnum = phnum & 0xFFFFU;

       return (1);
}