/**
 * collate.c - NTFS collation handling.  Originated from the Linux-NTFS project.
 *
 * Copyright (c) 2004 Anton Altaparmakov
 * Copyright (c) 2005 Yura Pakhuchiy
 *
 * This program/include file 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 2 of the License, or
 * (at your option) any later version.
 *
 * This program/include file 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 (in the main directory of the NTFS-3G
 * distribution in the file COPYING); if not, write to the Free Software
 * Foundation,Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
 */

#ifdef HAVE_CONFIG_H
#include "config.h"
#endif
#ifdef HAVE_STDLIB_H
#include <stdlib.h>
#endif
#ifdef HAVE_STRING_H
#include <string.h>
#endif
#ifdef HAVE_ERRNO_H
#include <errno.h>
#endif

#include "attrib.h"
#include "index.h"
#include "collate.h"
#include "debug.h"
#include "unistr.h"
#include "logging.h"

/**
 * ntfs_collate_binary - Which of two binary objects should be listed first
 * @vol: unused
 * @data1:
 * @data1_len:
 * @data2:
 * @data2_len:
 *
 * Description...
 *
 * Returns:
 */
static int ntfs_collate_binary(ntfs_volume *vol __attribute__((unused)),
                const void *data1, const int data1_len,
                const void *data2, const int data2_len)
{
        int rc;

        ntfs_log_trace("Entering.\n");
        rc = memcmp(data1, data2, min(data1_len, data2_len));
        if (!rc && (data1_len != data2_len)) {
                if (data1_len < data2_len)
                        rc = -1;
                else
                        rc = 1;
        }
        ntfs_log_trace("Done, returning %i.\n", rc);
        return rc;
}

/**
 * ntfs_collate_ntofs_ulong - Which of two long ints should be listed first
 * @vol: unused
 * @data1:
 * @data1_len:
 * @data2:
 * @data2_len:
 *
 * Description...
 *
 * Returns:
 */
static int ntfs_collate_ntofs_ulong(ntfs_volume *vol __attribute__((unused)),
                const void *data1, const int data1_len,
                const void *data2, const int data2_len)
{
        int rc;
        u32 d1, d2;

        ntfs_log_trace("Entering.\n");
        if (data1_len != data2_len || data1_len != 4) {
                ntfs_log_error("data1_len or/and data2_len not equal to 4.\n");
                return NTFS_COLLATION_ERROR;
        }
        d1 = le32_to_cpup(data1);
        d2 = le32_to_cpup(data2);
        if (d1 < d2)
                rc = -1;
        else {
                if (d1 == d2)
                        rc = 0;
                else
                        rc = 1;
        }
        ntfs_log_trace("Done, returning %i.\n", rc);
        return rc;
}

/**
 * ntfs_collate_ntofs_ulongs - Which of two le32 arrays should be listed first
 *
 * Returns: -1, 0 or 1 depending of how the arrays compare
 */

static int ntfs_collate_ntofs_ulongs(ntfs_volume *vol __attribute__((unused)),
                const void *data1, const int data1_len,
                const void *data2, const int data2_len)
{
        int rc;
        int len;
        const le32 *p1, *p2;
        u32 d1, d2;

        ntfs_log_trace("Entering.\n");
        if ((data1_len != data2_len) || (data1_len <= 0) || (data1_len & 3)) {
                ntfs_log_error("data1_len or data2_len not valid\n");
                return NTFS_COLLATION_ERROR;
        }
        p1 = (const le32*)data1;
        p2 = (const le32*)data2;
        len = data1_len;
        do {
                d1 = le32_to_cpup(p1);
                p1++;
                d2 = le32_to_cpup(p2);
                p2++;
        } while ((d1 == d2) && ((len -= 4) > 0));
        if (d1 < d2)
                rc = -1;
        else {
                if (d1 == d2)
                        rc = 0;
                else
                        rc = 1;
        }
        ntfs_log_trace("Done, returning %i.\n", rc);
        return rc;
}

/**
 * ntfs_collate_ntofs_security_hash - Which of two security descriptors
 *                    should be listed first
 * @vol: unused
 * @data1:
 * @data1_len:
 * @data2:
 * @data2_len:
 *
 * JPA compare two security hash keys made of two unsigned le32
 *
 * Returns: -1, 0 or 1 depending of how the keys compare
 */
static int ntfs_collate_ntofs_security_hash(ntfs_volume *vol __attribute__((unused)),
                const void *data1, const int data1_len,
                const void *data2, const int data2_len)
{
        int rc;
        u32 d1, d2;
        const le32 *p1, *p2;

        ntfs_log_trace("Entering.\n");
        if (data1_len != data2_len || data1_len != 8) {
                ntfs_log_error("data1_len or/and data2_len not equal to 8.\n");
                return NTFS_COLLATION_ERROR;
        }
        p1 = (const le32*)data1;
        p2 = (const le32*)data2;
        d1 = le32_to_cpup(p1);
        d2 = le32_to_cpup(p2);
        if (d1 < d2)
                rc = -1;
        else {
                if (d1 > d2)
                        rc = 1;
                else {
                        p1++;
                        p2++;
                        d1 = le32_to_cpup(p1);
                        d2 = le32_to_cpup(p2);
                        if (d1 < d2)
                                rc = -1;
                        else {
                                if (d1 > d2)
                                        rc = 1;
                                else
                                        rc = 0;
                        }
                }
        }
        ntfs_log_trace("Done, returning %i.\n", rc);
        return rc;
}

/**
 * ntfs_collate_file_name - Which of two filenames should be listed first
 * @vol:
 * @data1:
 * @data1_len: unused
 * @data2:
 * @data2_len: unused
 *
 * Description...
 *
 * Returns:
 */
static int ntfs_collate_file_name(ntfs_volume *vol,
                const void *data1, const int data1_len __attribute__((unused)),
                const void *data2, const int data2_len __attribute__((unused)))
{
        const FILE_NAME_ATTR *file_name_attr1;
        const FILE_NAME_ATTR *file_name_attr2;
        int rc;

        ntfs_log_trace("Entering.\n");
        file_name_attr1 = (const FILE_NAME_ATTR*)data1;
        file_name_attr2 = (const FILE_NAME_ATTR*)data2;
        rc = ntfs_names_full_collate(
                        (ntfschar*)&file_name_attr1->file_name,
                        file_name_attr1->file_name_length,
                        (ntfschar*)&file_name_attr2->file_name,
                        file_name_attr2->file_name_length,
                        CASE_SENSITIVE, vol->upcase, vol->upcase_len);
        ntfs_log_trace("Done, returning %i.\n", rc);
        return rc;
}

/*
 *              Get a pointer to appropriate collation function.
 *
 *      Returns NULL if the needed function is not implemented
 */

COLLATE ntfs_get_collate_function(COLLATION_RULES cr)
{
        COLLATE collate;

        switch (cr) {
        case COLLATION_BINARY :
                collate = ntfs_collate_binary;
                break;
        case COLLATION_FILE_NAME :
                collate = ntfs_collate_file_name;
                break;
        case COLLATION_NTOFS_SECURITY_HASH :
                collate = ntfs_collate_ntofs_security_hash;
                break;
        case COLLATION_NTOFS_ULONG :
                collate = ntfs_collate_ntofs_ulong;
                break;
        case COLLATION_NTOFS_ULONGS :
                collate = ntfs_collate_ntofs_ulongs;
                break;
        default :
                errno = EOPNOTSUPP;
                collate = (COLLATE)NULL;
                break;
        }
        return (collate);
}