htelfsym.cc

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/* 
 *      HT Editor
 *      htelfsym.cc
 *
 *      Copyright (C) 1999-2002 Stefan Weyergraf (stefan@weyergraf.de)
 *
 *      This program is free software; you can redistribute it and/or modify
 *      it under the terms of the GNU General Public License version 2 as
 *      published by the Free Software Foundation.
 *
 *      This program 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 this program; if not, write to the Free Software
 *      Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
 */

#include "elfstruc.h"
#include "htatom.h"
#include "htelf.h"
#include "htelfsym.h"
#include "httag.h"
#include "formats.h"
#include "snprintf.h"

#include <stdlib.h>

static int_hash elf_st_bind[] =
{
        {ELF_STB_LOCAL,         "local"},
        {ELF_STB_GLOBAL,        "global"},
        {ELF_STB_WEAK,          "weak"},
        {0, 0}
};

static int_hash elf_st_type[] =
{
        {ELF_STT_NOTYPE,        "no type"},
        {ELF_STT_OBJECT,        "object"},
        {ELF_STT_FUNC,          "func"},
        {ELF_STT_SECTION,       "section"},
        {ELF_STT_FILE,          "file"},
        {ELF_STT_COMMON,        "common"},
        {0, 0}
};

static ht_view *htelfsymboltable_init(bounds *b, ht_streamfile *file, ht_format_group *group)
{
        ht_elf_shared_data *elf_shared=(ht_elf_shared_data *)group->get_shared_data();

        if (elf_shared->ident.e_ident[ELF_EI_CLASS]!=ELFCLASS32) return 0;

        UINT skip = elf_shared->symtables;
        UINT symtab_shidx = ELF_SHN_UNDEF;
        for (UINT i=1; i<elf_shared->sheaders.count; i++) {
                if ((elf_shared->sheaders.sheaders32[i].sh_type == ELF_SHT_SYMTAB) || (elf_shared->sheaders.sheaders32[i].sh_type==ELF_SHT_DYNSYM)) {
                        if (!skip--) {
                                symtab_shidx = i;
                                break;
                        }
                }
        }
        if (!isValidELFSectionIdx(elf_shared, symtab_shidx)) return NULL;

        FILEOFS h = elf_shared->sheaders.sheaders32[symtab_shidx].sh_offset;

        /* associated string table offset (from sh_link) */
        FILEOFS sto = elf_shared->sheaders.sheaders32[elf_shared->sheaders.sheaders32[symtab_shidx].sh_link].sh_offset;

        char *symtab_name;
        if (!isValidELFSectionIdx(elf_shared, elf_shared->header32.e_shstrndx) ||
        file->seek(elf_shared->sheaders.sheaders32[elf_shared->header32.e_shstrndx].sh_offset+elf_shared->sheaders.sheaders32[symtab_shidx].sh_name)
        || !((symtab_name=fgetstrz(file))))
                symtab_name = "?";

        char desc[128];
        ht_snprintf(desc, sizeof desc, DESC_ELF_SYMTAB, symtab_name, symtab_shidx);
        free(symtab_name);

        ht_uformat_viewer *v=new ht_uformat_viewer();
        v->init(b, desc, VC_EDIT | VC_SEARCH, file, group);

        ht_mask_sub *m = new ht_mask_sub();
        m->init(file, 0);

        register_atom(ATOM_ELF_ST_BIND, elf_st_bind);

        char t[256];
        ht_snprintf(t, sizeof t, "* ELF symtab at offset %08x", h);

        m->add_mask(t);

        m->add_mask("idx  binding  type     value    size     section     name");

        bool elf_bigendian = (elf_shared->ident.e_ident[ELF_EI_DATA] == ELFDATA2MSB);
        UINT symnum = elf_shared->sheaders.sheaders32[symtab_shidx].sh_size / sizeof (ELF_SYMBOL32);
        for (UINT i=0; i<symnum; i++) {
                ELF_SYMBOL32 sym;
                file->seek(h+i*sizeof (ELF_SYMBOL32));
                file->read(&sym, sizeof sym);
                create_host_struct(&sym, ELF_SYMBOL32_struct, elf_shared->byte_order);
                file->seek(sto+sym.st_name);          
                char *name = fgetstrz(file);
                /* FIXME: error handling (also in elf_analy.cc) */
                if (!name) continue;

                char *tt = t;

                tt += ht_snprintf(tt, sizeof t - (tt-t), "%04x ", i);

                char *bind = matchhash(ELF32_ST_BIND(sym.st_info), elf_st_bind);
                if (bind) {
                        tt += ht_snprintf(tt, sizeof t - (tt-t), "%-8s ", bind);
                } else {
                        tt += ht_snprintf(tt, sizeof t - (tt-t), "? (%d) ", ELF32_ST_BIND(sym.st_info));
                }

                char *type = matchhash(ELF32_ST_TYPE(sym.st_info), elf_st_type);
                if (type) {
                        tt += ht_snprintf(tt, sizeof t - (tt-t), "%-8s ", type);
                } else {
                        tt += ht_snprintf(tt, sizeof t - (tt-t), "? (%d) ", ELF32_ST_TYPE(sym.st_info));
                }

                FILEOFS so = elf_shared->sheaders.sheaders32[elf_shared->header32.e_shstrndx].sh_offset;
                tt = tag_make_edit_dword(tt, h+i*sizeof (ELF_SYMBOL32)+4, elf_bigendian ? tag_endian_big : tag_endian_little);
                *tt++ = ' ';
                tt = tag_make_edit_dword(tt, h+i*sizeof (ELF_SYMBOL32)+8, elf_bigendian ? tag_endian_big : tag_endian_little);
                *tt++ = ' ';
                *tt = 0;
                switch (sym.st_shndx) {
                        case ELF_SHN_UNDEF:
                                tt += ht_snprintf(tt, sizeof t - (tt-t), "*undefined  ");
                                break;
                        case ELF_SHN_ABS:
                                tt += ht_snprintf(tt, sizeof t - (tt-t), "*absolute   ");
                                break;
                        case ELF_SHN_COMMON:
                                tt += ht_snprintf(tt, sizeof t - (tt-t), "*common     ");
                                break;
                        default: {
                                char *s;
                                if (!isValidELFSectionIdx(elf_shared, sym.st_shndx)
                                || file->seek(so+elf_shared->sheaders.sheaders32[sym.st_shndx].sh_name)
                                || !((s = fgetstrz(file)))) s = "?";
                                tt += ht_snprintf(tt, sizeof t - (tt-t), "%-11s ", s);
                                free(s);
                                break;
                        }
                }
                tt += ht_snprintf(tt, sizeof t - (tt-t), "%s", name);
                free(name);
                m->add_mask(t);
        }

        v->insertsub(m);
        return v;
}

format_viewer_if htelfsymboltable_if = {
        htelfsymboltable_init,
        0
};

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