source: mainline/uspace/srv/net/structures/char_map.c@ 21580dd

/*
 * Copyright (c) 2009 Lukas Mejdrech
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 *
 * - Redistributions of source code must retain the above copyright
 *   notice, this list of conditions and the following disclaimer.
 * - Redistributions in binary form must reproduce the above copyright
 *   notice, this list of conditions and the following disclaimer in the
 *   documentation and/or other materials provided with the distribution.
 * - The name of the author may not be used to endorse or promote products
 *   derived from this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */

/** @addtogroup net
 *  @{
 */

/** @file
 *  Character string to integer map implementation.
 *  @see char_map.h
 */

#include <errno.h>
#include <malloc.h>
#include <mem.h>
#include <unistd.h>

#include "char_map.h"

/** Internal magic value for a&nbsp;consistency check.
 */
#define CHAR_MAP_MAGIC_VALUE    0x12345611

/** Adds the value with the key to the map.
 *  Creates new nodes to map the key.
 *  @param[in,out] map The character string to integer map.
 *  @param[in] identifier The key zero ('\\0') terminated character string. The key character string is processed until the first terminating zero ('\\0') character after the given length is found.
 *  @param[in] length The key character string length. The parameter may be zero (0) which means that the string is processed until the terminating zero ('\\0') character is found.
 *  @param[in] value The integral value to be stored for the key character string.
 *  @returns EOK on success.
 *  @returns ENOMEM if there is not enough memory left.
 *  @returns EEXIST if the key character string is already used.
 */
int     char_map_add_item( char_map_ref map, const char * identifier, size_t length, const int value );

/** Returns the node assigned to the key from the map.
 *  @param[in] map The character string to integer map.
 *  @param[in] identifier The key zero ('\\0') terminated character string. The key character string is processed until the first terminating zero ('\\0') character after the given length is found.
 *  @param[in] length The key character string length. The parameter may be zero (0) which means that the string is processed until the terminating zero ('\\0') character is found.
 *  @returns The node holding the integral value assigned to the key character string.
 *  @returns NULL if the key is not assigned a&nbsp;node.
 */
char_map_ref    char_map_find_node( const char_map_ref map, const char * identifier, const size_t length );

/** Returns the value assigned to the map.
 *  @param[in] map The character string to integer map.
 *  @returns The integral value assigned to the map.
 *  @returns CHAR_MAP_NULL if the map is not assigned a&nbsp;value.
 */
int     char_map_get_value( const char_map_ref map );

/** Checks if the map is valid.
 *  @param[in] map The character string to integer map.
 *  @returns TRUE if the map is valid.
 *  @returns FALSE otherwise.
 */
int     char_map_is_valid( const char_map_ref map );

int char_map_add( char_map_ref map, const char * identifier, size_t length, const int value ){
        if( char_map_is_valid( map ) && ( identifier ) && (( length ) || ( * identifier ))){
                int     index;

                for( index = 0; index < map->next; ++ index ){
                        if( map->items[ index ]->c == * identifier ){
                                ++ identifier;
                                if(( length > 1 ) || (( length == 0 ) && ( * identifier ))){
                                        return char_map_add( map->items[ index ], identifier, length ? length - 1 : 0, value );
                                }else{
                                        if( map->items[ index ]->value != CHAR_MAP_NULL ) return EEXISTS;
                                        map->items[ index ]->value = value;
                                        return EOK;
                                }
                        }
                }
                return char_map_add_item( map, identifier, length, value );
        }
        return EINVAL;
}

int char_map_add_item( char_map_ref map, const char * identifier, size_t length, const int value ){
        if( map->next == ( map->size - 1 )){
                char_map_ref    * tmp;

                tmp = ( char_map_ref * ) realloc( map->items, sizeof( char_map_ref ) * 2 * map->size );
                if( ! tmp ) return ENOMEM;
                map->size *= 2;
                map->items = tmp;
        }
        map->items[ map->next ] = ( char_map_ref ) malloc( sizeof( char_map_t ));
        if( ! map->items[ map->next ] ) return ENOMEM;
        if( char_map_initialize( map->items[ map->next ] ) != EOK ){
                free( map->items[ map->next ] );
                map->items[ map->next ] = NULL;
                return ENOMEM;
        }
        map->items[ map->next ]->c = * identifier;
        ++ identifier;
        ++ map->next;
        if(( length > 1 ) || (( length == 0 ) && ( * identifier ))){
                map->items[ map->next - 1 ]->value = CHAR_MAP_NULL;
                return char_map_add_item( map->items[ map->next - 1 ], identifier, length ? length - 1 : 0, value );
        }else{
                map->items[ map->next - 1 ]->value = value;
        }
        return EOK;
}

void char_map_destroy( char_map_ref map ){
        if( char_map_is_valid( map )){
                int     index;

                map->magic = 0;
                for( index = 0; index < map->next; ++ index ){
                        char_map_destroy( map->items[ index ] );
                }
                free( map->items );
                map->items = NULL;
        }
}

int char_map_exclude( char_map_ref map, const char * identifier, size_t length ){
        char_map_ref    node;

        node = char_map_find_node( map, identifier, length );
        if( node ){
                int     value;

                value = node->value;
                node->value = CHAR_MAP_NULL;
                return value;
        }
        return CHAR_MAP_NULL;
}

int char_map_find( const char_map_ref map, const char * identifier, size_t length ){
        char_map_ref    node;

        node = char_map_find_node( map, identifier, length );
        return node ? node->value : CHAR_MAP_NULL;
}

char_map_ref char_map_find_node( const char_map_ref map, const char * identifier, size_t length ){
        if( ! char_map_is_valid( map )) return NULL;
        if( length || ( * identifier )){
                int     index;

                for( index = 0; index < map->next; ++ index ){
                        if( map->items[ index ]->c == * identifier ){
                                ++ identifier;
                                if( length == 1 ) return map->items[ index ];
                                return char_map_find_node( map->items[ index ], identifier, length ? length - 1 : 0 );
                        }
                }
                return NULL;
        }
        return map;
}

int char_map_get_value( const char_map_ref map ){
        return char_map_is_valid( map ) ? map->value : CHAR_MAP_NULL;
}

int char_map_initialize( char_map_ref map ){
        if( ! map ) return EINVAL;
        map->c = '\0';
        map->value = CHAR_MAP_NULL;
        map->size = 2;
        map->next = 0;
        map->items = malloc( sizeof( char_map_ref ) * map->size );
        if( ! map->items ){
                map->magic = 0;
                return ENOMEM;
        }
        map->items[ map->next ] = NULL;
        map->magic = CHAR_MAP_MAGIC_VALUE;
        return EOK;
}

int char_map_is_valid( const char_map_ref map ){
        return map && ( map->magic == CHAR_MAP_MAGIC_VALUE );
}

int char_map_update( char_map_ref map, const char * identifier, const size_t length, const int value ){
        char_map_ref    node;

//      if( ! char_map_is_valid( map )) return EINVAL;
        node = char_map_find_node( map, identifier, length );
        if( node ){
                node->value = value;
                return EOK;
        }else{
                return char_map_add( map, identifier, length, value );
        }
}

/** @}
 */