Atlas - SDL_list.c
Home / ext / SDL / src
Lines: 1 | Size: 3687 bytes
[Download] [Show on GitHub] [Search similar files] [Raw] [Raw (proxy)] 
[FILE BEGIN]
1/*
2  Simple DirectMedia Layer
3  Copyright (C) 1997-2026 Sam Lantinga <[email protected]>
4
5  This software is provided 'as-is', without any express or implied
6  warranty.  In no event will the authors be held liable for any damages
7  arising from the use of this software.
8
9  Permission is granted to anyone to use this software for any purpose,
10  including commercial applications, and to alter it and redistribute it
11  freely, subject to the following restrictions:
12
13  1. The origin of this software must not be misrepresented; you must not
14     claim that you wrote the original software. If you use this software
15     in a product, an acknowledgment in the product documentation would be
16     appreciated but is not required.
17  2. Altered source versions must be plainly marked as such, and must not be
18     misrepresented as being the original software.
19  3. This notice may not be removed or altered from any source distribution.
20*/
21#include "SDL_internal.h"
22
23#include "./SDL_list.h"
24
25// Append
26bool SDL_ListAppend(SDL_ListNode **head, void *ent)
27{
28    SDL_ListNode *cursor;
29    SDL_ListNode *node;
30
31    if (!head) {
32        return false;
33    }
34
35    node = (SDL_ListNode *)SDL_malloc(sizeof(*node));
36    if (!node) {
37        return false;
38    }
39    node->entry = ent;
40    node->next = NULL;
41
42    if (*head) {
43        cursor = *head;
44        while (cursor->next) {
45            cursor = cursor->next;
46        }
47        cursor->next = node;
48    } else {
49        *head = node;
50    }
51
52    return true;
53}
54
55bool SDL_ListInsertAtPosition(SDL_ListNode **head, int pos, void *ent)
56{
57    SDL_ListNode *cursor;
58    SDL_ListNode *node;
59    int i;
60
61    if (pos == -1) {
62        return SDL_ListAppend(head, ent);
63    }
64
65    if (!pos) {
66        node = (SDL_ListNode *)SDL_malloc(sizeof(*node));
67        if (!node) {
68            return false;
69        }
70        node->entry = ent;
71
72        if (*head) {
73            node->next = *head;
74        } else {
75            node->next = NULL;
76        }
77
78        *head = node;
79    }
80
81    cursor = *head;
82    for (i = 1; i < pos - 1 && cursor; i++) {
83        cursor = cursor->next;
84    }
85
86    if (!cursor) {
87        return SDL_ListAppend(head, ent);
88    }
89
90    node = (SDL_ListNode *)SDL_malloc(sizeof(*node));
91    if (!node) {
92        return false;
93    }
94    node->entry = ent;
95    node->next = cursor->next;
96    cursor->next = node;
97
98    return true;
99}
100
101// Push
102bool SDL_ListAdd(SDL_ListNode **head, void *ent)
103{
104    SDL_ListNode *node = (SDL_ListNode *)SDL_malloc(sizeof(*node));
105
106    if (!node) {
107        return false;
108    }
109
110    node->entry = ent;
111    node->next = *head;
112    *head = node;
113    return true;
114}
115
116// Pop from end as a FIFO (if add with SDL_ListAdd)
117void SDL_ListPop(SDL_ListNode **head, void **ent)
118{
119    SDL_ListNode **ptr = head;
120
121    // Invalid or empty
122    if (!head || !*head) {
123        return;
124    }
125
126    while ((*ptr)->next) {
127        ptr = &(*ptr)->next;
128    }
129
130    if (ent) {
131        *ent = (*ptr)->entry;
132    }
133
134    SDL_free(*ptr);
135    *ptr = NULL;
136}
137
138void SDL_ListRemove(SDL_ListNode **head, void *ent)
139{
140    SDL_ListNode **ptr = head;
141
142    while (*ptr) {
143        if ((*ptr)->entry == ent) {
144            SDL_ListNode *tmp = *ptr;
145            *ptr = (*ptr)->next;
146            SDL_free(tmp);
147            return;
148        }
149        ptr = &(*ptr)->next;
150    }
151}
152
153void SDL_ListClear(SDL_ListNode **head)
154{
155    SDL_ListNode *l = *head;
156    *head = NULL;
157    while (l) {
158        SDL_ListNode *tmp = l;
159        l = l->next;
160        SDL_free(tmp);
161    }
162}
163
164int SDL_ListCountEntries(SDL_ListNode **head)
165{
166    SDL_ListNode *node;
167    int count = 0;
168
169    for (node = *head; node; node = node->next) {
170        ++count;
171    }
172    return count;
173}
174
[FILE END]
(C) 2025 0x4248
(C) 2025 4248 Media and 4248 Systems, All part of 0x4248
See LICENCE files for more information. Not all files are by 0x4248 always check Licencing.