librtld/common/syms.c

	syms.c revision 7c478bd95313f5f23a4c958a745db2134aa03244
/*
 * CDDL HEADER START
 *
 * The contents of this file are subject to the terms of the
 * Common Development and Distribution License, Version 1.0 only
 * (the "License").  You may not use this file except in compliance
 * with the License.
 *
 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
 * or http://www.opensolaris.org/os/licensing.
 * See the License for the specific language governing permissions
 * and limitations under the License.
 *
 * When distributing Covered Code, include this CDDL HEADER in each
 * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
 * If applicable, add the following below this CDDL HEADER, with the
 * fields enclosed by brackets "[]" replaced with your own identifying
 * information: Portions Copyright [yyyy] [name of copyright owner]
 *
 * CDDL HEADER END
 */
/*
 *  Copyright (c) 1995-2001 by Sun Microsystems, Inc.
 *  All rights reserved.
 *
 * Update the symbol table entries:
 *
 *  o   If addr is non-zero then every symbol entry is updated to indicate the
 *  new location to which the object will be mapped.
 *
 *  o   The address of the `_edata' and `_end' symbols, and their associated
 *  section, is updated to reflect any new heap addition.
 */
#pragma ident   "%Z%%M% %I% %E% SMI"

#include    <libelf.h>
#include    <string.h>
#include    "sgs.h"
#include    "machdep.h"
#include    "msg.h"
#include    "_librtld.h"

void
update_sym(Cache *cache, Cache *_cache, Addr edata, Half endx, Addr addr)
{
    char    *strs;
    Sym *syms;
    Shdr    *shdr;
    Xword   symn, cnt;

    /*
     * Set up to read the symbol table and its associated string table.
     */
    shdr = _cache->c_shdr;
    syms = (Sym *)_cache->c_data->d_buf;
    symn = shdr->sh_size / shdr->sh_entsize;

    strs = (char *)cache[shdr->sh_link].c_data->d_buf;

    /*
     * Loop through the symbol table looking for `_end' and `_edata'.
     */
    for (cnt = 0; cnt < symn; cnt++, syms++) {
        char    *name = strs + syms->st_name;

        if (addr) {
            if (syms->st_value)
                syms->st_value += addr;
        }

        if ((name[0] != '_') || (name[1] != 'e'))
            continue;
        if (strcmp(name, MSG_ORIG(MSG_SYM_END)) &&
            strcmp(name, MSG_ORIG(MSG_SYM_EDATA)))
            continue;

        syms->st_value = edata + addr;
        if (endx)
            syms->st_shndx = endx;
    }
}