/* Chrysalide - Outil d'analyse de fichiers binaires
 * helper_mips.c - gestion auxiliaire de l'architecture MIPS
 *
 * Copyright (C) 2009-2017 Cyrille Bagard
 *
 *  This file is part of Chrysalide.
 *
 *  Chrysalide is free software; you can redistribute it and/or modify
 *  it under the terms of the GNU General Public License as published by
 *  the Free Software Foundation; either version 3 of the License, or
 *  (at your option) any later version.
 *
 *  Chrysalide 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 General Public License for more details.
 *
 *  You should have received a copy of the GNU General Public License
 *  along with Foobar.  If not, see <http://www.gnu.org/licenses/>.
 */


#include "helper_mips.h"


#include <string.h>


#include "elf-int.h"



/******************************************************************************
*                                                                             *
*  Paramètres  : format    = description de l'exécutable à compléter.         *
*                dyn_start = début des informations dynamiques associées.     *
*                dyn_size  = taille de la zone associée.                      *
*                str_start = début de la zone de chaîne de caractères.        *
*                str_size  = taille de la zone de chaînes de caractères.      *
*                                                                             *
*  Description : Déduit les adresses effectives des appels externes.          *
*                                                                             *
*  Retour      : Bilan de l'opération.                                        *
*                                                                             *
*  Remarques   : -                                                            *
*                                                                             *
******************************************************************************/

bool g_elf_format_find_mips_dynamic_symbols(elf_format *format, off_t dyn_start, off_t dyn_size, off_t str_start, off_t str_size)
{
    off_t iter;                             /* Boucle de parcours          */
    Elf_Sym symbol;                         /* Symbole ELF lu              */
    off_t name_pos;                         /* Localisation du nom         */

    if (dyn_size % ELF_SIZEOF_SYM(format) != 0) return false;

    for (iter = dyn_start; iter < (dyn_start + dyn_size); iter += ELF_SIZEOF_SYM(format))
    {
        memcpy(&symbol, &EXE_FORMAT(format)->content[iter], ELF_SIZEOF_SYM(format));

        if (ELF_ST_TYPE(ELF_SYM(format, symbol, st_info)) != STT_FUNC) continue;

        if (ELF_SYM(format, symbol, st_value) == 0) continue;

        name_pos = ELF_SYM(format, symbol, st_name);

        /* Sécurité anti-débordements */
        if (name_pos >= str_size) continue;

        /* Si le symbole possède un nom... */
        if (strlen(&EXE_FORMAT(format)->content[str_start + name_pos]) > 0)
        {
            format->symbols = (elf_symbol *)realloc(format->symbols, ++format->sym_count * sizeof(elf_symbol));

            format->symbols[format->sym_count - 1].name = &EXE_FORMAT(format)->content[str_start + name_pos];
            format->symbols[format->sym_count - 1].address = ELF_SYM(format, symbol, st_value);

        }

    }

    return true;

}