ucx: src/linked_list.c@e6a8f7fb0c45

     1 /*

     2  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS HEADER.

     3  *

     4  * Copyright 2021 Mike Becker, Olaf Wintermann All rights reserved.

     5  *

     6  * Redistribution and use in source and binary forms, with or without

     7  * modification, are permitted provided that the following conditions are met:

     8  *

     9  *   1. Redistributions of source code must retain the above copyright

    10  *      notice, this list of conditions and the following disclaimer.

    11  *

    12  *   2. Redistributions in binary form must reproduce the above copyright

    13  *      notice, this list of conditions and the following disclaimer in the

    14  *      documentation and/or other materials provided with the distribution.

    15  *

    16  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"

    17  * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE

    18  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE

    19  * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE

    20  * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR

    21  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF

    22  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS

    23  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN

    24  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)

    25  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE

    26  * POSSIBILITY OF SUCH DAMAGE.

    27  */

    29 #include "cx/linked_list.h"

    30 #include <stdint.h>

    31 #include <string.h>

    33 /* LOW LEVEL LINKED LIST FUNCTIONS */

    35 #define CX_LL_PTR(cur, off) ((void**)(((char*)cur)+off))

    37 void *cx_linked_list_last(void **begin, void **end, ptrdiff_t loc_next) {

    38     if (end != NULL) {

    39         return *end;

    40     } else {

    41         if (begin == NULL || *begin == NULL)

    42             return NULL;

    44         void *cur = *begin;

    45         void *last;

    46         do {

    47             last = cur;

    48         } while ((cur = *CX_LL_PTR(cur, loc_next)) != NULL);

    50         return last;

    51     }

    52 }

    54 int cx_linked_list_add(void **begin, void **end, ptrdiff_t loc_next, ptrdiff_t loc_prev, void *newnode) {

    55     // TODO: how do we report error messages?

    56     if (loc_next < 0 || (begin == NULL && end == NULL)) {

    57         return 1;

    58     }

    60     void *last = cx_linked_list_last(begin, end, loc_next);

    61     if (last == NULL) {

    62         if (begin == NULL) {

    63             return 1;

    64         } else {

    65             *begin = newnode;

    66             return 0;

    67         }

    68     }

    70     void **next = CX_LL_PTR(last, loc_next);

    71     *next = newnode;

    72     if (loc_prev >= 0) {

    73         void **prev = CX_LL_PTR(newnode, loc_prev);

    74         *prev = last;

    75     }

    77     return 0;

    78 }

    80 /* HIGH LEVEL LINKED LIST IMPLEMENTATION */

    82 typedef struct {

    83     void *begin;

    84     void *end;

    85 } cx_linked_list;

    87 int cx_ll_add(cx_list *list, void *elem) {

    88     cx_linked_list *listdata = list->listdata;

    89     CxAllocator allocator = list->allocator;

    91     /*

    92      * Memory layout:

    93      * next : sizeof(void*)

    94      * prev : sizeof(void*)

    95      * data : itemsize

    96      */

    97     void *node = cxMalloc(allocator,2*sizeof(void*)+list->itemsize);

    98     if (node == NULL)

    99         return 1;

   101     memset(node, 0, sizeof(void*));

   102     memcpy(node+2, elem, list->itemsize);

   104     int ret = cx_linked_list_add(

   105             &listdata->begin,

   106             &listdata->end,

   107             0,

   108             sizeof(void*),

   109             node

   110     );

   111     if (ret == 0) {

   112         list->size++;

   113         return 0;

   114     } else {

   115         return ret;

   116     }

   117 }

   119 int cx_ll_insert(cx_list *list, size_t index, void *elem) {

   120     cx_linked_list *listdata = list->listdata;

   121     // TODO: implement using low level API

   122     return 1;

   123 }

   125 void *cx_ll_remove(cx_list *list, size_t index) {

   126     cx_linked_list *listdata = list->listdata;

   127     // TODO: implement using low level API

   128     return NULL;

   129 }

   131 size_t cx_ll_find(cx_list *list, void *elem) {

   132     cx_linked_list *listdata = list->listdata;

   133     // TODO: implement using low level API

   134     return 0;

   135 }

   138 cx_list_class cx_linked_list_class = {

   139         cx_ll_add,

   140         cx_ll_insert,

   141         cx_ll_remove,

   142         cx_ll_find

   143 };

   145 CxList cxLinkedListCreate(CxAllocator allocator, CxListComparator comparator, size_t itemsize) {

   146     CxList list = cxMalloc(allocator, sizeof(list));

   147     if (list == NULL)

   148         return NULL;

   150     list->cl = &cx_linked_list_class;

   151     list->data.allocator = allocator;

   152     list->data.cmpfunc = comparator;

   153     list->data.size = 0;

   154     list->data.itemsize = itemsize;

   155     list->data.capacity = SIZE_MAX;

   156     list->data.listdata = cxCalloc(allocator, 1, sizeof(cx_linked_list));

   157     if (list->data.listdata == NULL) {

   158         cxFree(allocator, list);

   159         return NULL;

   160     }

   161 }

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