/*

 * Copyright (c) 2016 SAP SE. All rights reserved.

 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.

 *

 * This code is free software; you can redistribute it and/or modify it

 * under the terms of the GNU General Public License version 2 only, as

 * published by the Free Software Foundation.

 *

 * This code 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

 * version 2 for more details (a copy is included in the LICENSE file that

 * accompanied this code).

 *

 * You should have received a copy of the GNU General Public License version

 * 2 along with this work; if not, write to the Free Software Foundation,

 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.

 *

 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA

 * or visit www.oracle.com if you need additional information or have any

 * questions.

 */

#include <stdio.h>

#include <sys/ldr.h>

#include "java_md_aix.h"

static unsigned char dladdr_buffer[0x4000];

static int fill_dll_info(void) {

    return loadquery(L_GETINFO, dladdr_buffer, sizeof(dladdr_buffer));

}

static int dladdr_dont_reload(void *addr, Dl_info *info) {

    const struct ld_info *p = (struct ld_info *)dladdr_buffer;

    memset((void *)info, 0, sizeof(Dl_info));

    for (;;) {

        if (addr >= p->ldinfo_textorg &&

            addr < (((char*)p->ldinfo_textorg) + p->ldinfo_textsize))

        {

            info->dli_fname = p->ldinfo_filename;

            return 1;

        }

        if (!p->ldinfo_next) {

            break;

        }

        p = (struct ld_info *)(((char *)p) + p->ldinfo_next);

    }

    return 0;

}

int dladdr(void *addr, Dl_info *info) {

    static int loaded = 0;

    int rc = 0;

    void *addr0;

    if (!addr) {

        return rc;

    }

    if (!loaded) {

        if (fill_dll_info() == -1)

            return rc;

        loaded = 1;

    }

    // first try with addr on cached data

    rc = dladdr_dont_reload(addr, info);

    // addr could be an AIX function descriptor, so try dereferenced version

    if (rc == 0) {

        addr0 = *((void **)addr);

        rc = dladdr_dont_reload(addr0, info);

    }

    // if we had no success until now, maybe loadquery info is outdated.

    // refresh and retry

    if (rc == 0) {

        if (fill_dll_info() == -1)

            return rc;

        rc = dladdr_dont_reload(addr, info);

        if (rc == 0) {

            rc = dladdr_dont_reload(addr0, info);

        }

    }

    return rc;

}