blob: 99d4e13493dca594535cbc8de13659c706d2f96b (
plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
|
#include <stdlib.h>
#include <string.h>
#include "list.h"
/* allocates and initialises list structure; returns NULL if malloc fails */
struct list *list_create() {
struct list *list = malloc(sizeof(struct list));
if (list)
memset(list, 0, sizeof(struct list));
return list;
}
/* frees all memory associated with the list */
void list_destroy(struct list *list) {
struct list_node *node, *next;
if (!list)
return;
for (node = list->first; node; node = next) {
free(node->data);
next = node->next;
free(node);
}
free(list);
}
/* appends entry to list; returns 1 if ok, 0 if malloc fails */
int list_push(struct list *list, void *data) {
struct list_node *node;
node = malloc(sizeof(struct list_node));
if (!node)
return 0;
node->next = NULL;
node->data = data;
if (list->first)
list->last->next = node;
else
list->first = node;
list->last = node;
return 1;
}
/* removes first entry from list and returns data */
void *list_shift(struct list *list) {
struct list_node *node;
void *data;
if (!list->first)
return NULL;
node = list->first;
list->first = node->next;
if (!list->first)
list->last = NULL;
data = node->data;
free(node);
return data;
}
/* removes all entries with matching data pointer */
void list_removedata(struct list *list, void *data) {
struct list_node *node, *t;
if (!list || !list->first)
return;
node = list->first;
while (node->data == data) {
list->first = node->next;
free(node);
node = list->first;
if (!node) {
list->last = NULL;
return;
}
}
for (; node->next; node = node->next)
if (node->next->data == data) {
t = node->next;
node->next = t->next;
free(t);
if (!node->next) { /* we removed the last one */
list->last = node;
return;
}
}
}
/* returns first node */
struct list_node *list_first(struct list *list) {
return list ? list->first : NULL;
}
/* returns the next node after the argument */
struct list_node *list_next(struct list_node *node) {
return node->next;
}
|