linked_list.c

00001 /*
00002  * Copyright (C) 2009-2012 by Matthias Ringwald
00003  *
00004  * Redistribution and use in source and binary forms, with or without
00005  * modification, are permitted provided that the following conditions
00006  * are met:
00007  *
00008  * 1. Redistributions of source code must retain the above copyright
00009  *    notice, this list of conditions and the following disclaimer.
00010  * 2. Redistributions in binary form must reproduce the above copyright
00011  *    notice, this list of conditions and the following disclaimer in the
00012  *    documentation and/or other materials provided with the distribution.
00013  * 3. Neither the name of the copyright holders nor the names of
00014  *    contributors may be used to endorse or promote products derived
00015  *    from this software without specific prior written permission.
00016  * 4. Any redistribution, use, or modification is done solely for
00017  *    personal benefit and not for any commercial purpose or for
00018  *    monetary gain.
00019  *
00020  * THIS SOFTWARE IS PROVIDED BY MATTHIAS RINGWALD AND CONTRIBUTORS
00021  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
00022  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
00023  * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL MATTHIAS
00024  * RINGWALD OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
00025  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
00026  * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
00027  * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
00028  * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
00029  * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF
00030  * THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
00031  * SUCH DAMAGE.
00032  *
00033  * Please inquire about commercial licensing options at btstack@ringwald.ch
00034  *
00035  */
00036 
00037 /*
00038  *  linked_list.c
00039  *
00040  *  Created by Matthias Ringwald on 7/13/09.
00041  */
00042 
00043 #include <btstack/linked_list.h>
00044 #include <stdlib.h>
00045 /**
00046  * tests if list is empty
00047  */
00048 int  linked_list_empty(linked_list_t * list){
00049     return *list == (void *) 0;
00050 }
00051 
00052 /**
00053  * linked_list_get_last_item
00054  */
00055 linked_item_t * linked_list_get_last_item(linked_list_t * list){        // <-- find the last item in the list
00056     linked_item_t *lastItem = NULL;
00057     linked_item_t *it;
00058     for (it = *list; it ; it = it->next){
00059         if (it) {
00060             lastItem = it;
00061         }
00062     }
00063     return lastItem;
00064 }
00065 
00066 
00067 /**
00068  * linked_list_add
00069  */
00070 void linked_list_add(linked_list_t * list, linked_item_t *item){        // <-- add item to list
00071     // check if already in list
00072     linked_item_t *it;
00073     for (it = *list; it ; it = it->next){
00074         if (it == item) {
00075             return;
00076         }
00077     }
00078     // add first
00079     item->next = *list;
00080     *list = item;
00081 }
00082 
00083 void linked_list_add_tail(linked_list_t * list, linked_item_t *item){   // <-- add item to list as last element
00084     // check if already in list
00085     linked_item_t *it;
00086     for (it = (linked_item_t *) list; it->next ; it = it->next){
00087         if (it->next == item) {
00088             return;
00089         }
00090     }
00091     item->next = (linked_item_t*) 0;
00092     it->next = item;
00093 }
00094 
00095 /**
00096  * Remove data_source from run loop
00097  *
00098  * @note: assumes that data_source_t.next is first element in data_source
00099  */
00100 int  linked_list_remove(linked_list_t * list, linked_item_t *item){    // <-- remove item from list
00101     linked_item_t *it;
00102     for (it = (linked_item_t *) list; it ; it = it->next){
00103         if (it->next == item){
00104             it->next =  item->next;
00105             return 0;
00106         }
00107     }
00108     return -1;
00109 }
00110 
00111 void linked_item_set_user(linked_item_t *item, void *user_data){
00112     item->next = (linked_item_t *) 0;
00113     item->user_data = user_data;
00114 }
00115 
00116 void * linked_item_get_user(linked_item_t *item) {
00117     return item->user_data;
00118 }
00119 
00120 #if 0
00121 #include <stdio.h>
00122 void test_linked_list(){
00123     linked_list_t testList = 0;
00124     linked_item_t itemA;
00125     linked_item_t itemB;
00126     linked_item_t itemC;
00127     linked_item_set_user(&itemA, (void *) 0);
00128     linked_item_set_user(&itemB, (void *) 0);
00129     linked_list_add(&testList, &itemA);
00130     linked_list_add(&testList, &itemB);
00131     linked_list_add_tail(&testList, &itemC);
00132     // linked_list_remove(&testList, &itemB);
00133     linked_item_t *it;
00134     for (it = (linked_item_t *) &testList; it ; it = it->next){
00135         if (it->next == &itemA) printf("Item A\n");
00136         if (it->next == &itemB) printf("Item B\n");
00137         if (it->next == &itemC) printf("Item C\n");
00138         /* if (it->next == &itemB){
00139             it->next =  it->next;
00140             printf(" remove\n");
00141         } else {
00142             printf(" keep\n");
00143         
00144          */
00145     }
00146 }
00147 #endif