Mon, 08 Feb 2021 00:14:07 +0100
adds cxLinkedListWrap and cxLinkedListRecalculateSize
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_prev, ptrdiff_t loc_next, void *new_node) {
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 = new_node;
66 return 0;
67 }
68 }
70 void **next = CX_LL_PTR(last, loc_next);
71 *next = new_node;
72 if (loc_prev >= 0) {
73 void **prev = CX_LL_PTR(new_node, loc_prev);
74 *prev = last;
75 }
77 return 0;
78 }
80 /* HIGH LEVEL LINKED LIST IMPLEMENTATION */
82 struct cx_linked_list_node {
83 void *prev;
84 void *next;
85 char payload[];
86 };
88 typedef struct {
89 void *begin;
90 void *end;
91 ptrdiff_t loc_prev;
92 ptrdiff_t loc_next;
93 } cx_linked_list;
95 int cx_ll_add(cx_list *list, void *elem) {
96 cx_linked_list *listdata = (cx_linked_list *) list->listdata;
97 CxAllocator allocator = list->allocator;
99 struct cx_linked_list_node *node = cxMalloc(allocator,
100 sizeof(struct cx_linked_list_node) + list->itemsize);
101 if (node == NULL)
102 return 1;
104 node->next = NULL;
105 memcpy(node->payload, elem, list->itemsize);
107 int ret = cx_linked_list_add(
108 &listdata->begin,
109 &listdata->end,
110 offsetof(struct cx_linked_list_node, prev),
111 offsetof(struct cx_linked_list_node, next),
112 node
113 );
114 if (ret == 0) {
115 list->size++;
116 return 0;
117 } else {
118 return ret;
119 }
120 }
122 int cx_ll_insert(cx_list *list, size_t index, void *elem) {
123 cx_linked_list *listdata = (cx_linked_list *) list->listdata;
124 // TODO: implement using low level API
125 return 1;
126 }
128 void *cx_ll_remove(cx_list *list, size_t index) {
129 cx_linked_list *listdata = (cx_linked_list *) list->listdata;
130 // TODO: implement using low level API
131 return NULL;
132 }
134 size_t cx_ll_find(cx_list *list, void *elem) {
135 cx_linked_list *listdata = (cx_linked_list *) list->listdata;
136 // TODO: implement using low level API
137 return 0;
138 }
140 void *cx_ll_last(cx_list *list) {
141 cx_linked_list *listdata = (cx_linked_list *) list->listdata;
142 struct cx_linked_list_node *last = cx_linked_list_last(
143 NULL, &listdata->end, offsetof(struct cx_linked_list_node, next));
144 return &last->payload;
145 }
147 cx_list_class cx_linked_list_class = {
148 cx_ll_add,
149 cx_ll_insert,
150 cx_ll_remove,
151 cx_ll_find,
152 cx_ll_last
153 };
155 CxList cxLinkedListCreate(CxAllocator allocator, CxListComparator comparator, size_t item_size) {
156 CxLinkedListDesc desc;
157 desc.item_size = item_size;
158 desc.begin = desc.end = NULL;
159 desc.loc_prev = offsetof(struct cx_linked_list_node, prev);
160 desc.loc_next = offsetof(struct cx_linked_list_node, next);
162 return cxLinkedListWrap(allocator, comparator, desc);
163 }
165 CxList cxLinkedListWrap(CxAllocator allocator, CxListComparator comparator, CxLinkedListDesc desc) {
166 CxList list = cxMalloc(allocator, sizeof(list) + sizeof(cx_linked_list));
167 if (list == NULL)
168 return NULL;
170 list->cl = &cx_linked_list_class;
171 list->data.allocator = allocator;
172 list->data.cmpfunc = comparator;
173 list->data.itemsize = desc.item_size;
174 list->data.capacity = SIZE_MAX;
176 cx_linked_list *ll = (cx_linked_list *) list->data.listdata;
177 ll->begin = desc.begin ? *desc.begin : NULL;
178 ll->end = desc.end ? *desc.end : NULL;
179 ll->loc_prev = desc.loc_prev;
180 ll->loc_next = desc.loc_next;
181 cxLinkedListRecalculateSize(list);
183 return list;
184 }
186 size_t cxLinkedListRecalculateSize(CxList list) {
187 cx_linked_list *ll = (cx_linked_list *) list->data.listdata;
189 if (ll->begin == NULL) {
190 list->data.size = 0;
191 return 0;
192 } else {
193 void *cur = ll->begin;
194 size_t size;
195 do {
196 size++;
197 } while ((cur = *CX_LL_PTR(cur, ll->loc_next)) != NULL);
198 list->data.size = size;
199 return size;
200 }
201 }