/**
 * 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 );
}