source: mainline/uspace/srv/net/structures/char_map.c@ 6092b56e

/*
 * 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);
        }
}

/** @}
 */