pkgconf/libpkgconf/iter.h

0001 /*
0002  * iter.h
0003  * Linked lists and iterators.
0004  *
0005  * Copyright (c) 2013 pkgconf authors (see AUTHORS).
0006  *
0007  * Permission to use, copy, modify, and/or distribute this software for any
0008  * purpose with or without fee is hereby granted, provided that the above
0009  * copyright notice and this permission notice appear in all copies.
0010  *
0011  * This software is provided 'as is' and without any warranty, express or
0012  * implied.  In no event shall the authors be liable for any damages arising
0013  * from the use of this software.
0014  */
0015
0016 #ifndef LIBPKGCONF_ITER_H
0017 #define LIBPKGCONF_ITER_H
0018
0019 #ifdef __cplusplus
0020 extern "C" {
0021 #endif
0022
0023 typedef struct pkgconf_node_ pkgconf_node_t;
0024
0025 struct pkgconf_node_ {
0026     pkgconf_node_t *prev, *next;
0027     void *data;
0028 };
0029
0030 typedef struct {
0031     pkgconf_node_t *head, *tail;
0032     size_t length;
0033 } pkgconf_list_t;
0034
0035 #define PKGCONF_LIST_INITIALIZER        { NULL, NULL, 0 }
0036
0037 static inline void
0038 pkgconf_list_zero(pkgconf_list_t *list)
0039 {
0040     list->head = NULL;
0041     list->tail = NULL;
0042     list->length = 0;
0043 }
0044
0045 static inline void
0046 pkgconf_node_insert(pkgconf_node_t *node, void *data, pkgconf_list_t *list)
0047 {
0048     pkgconf_node_t *tnode;
0049
0050     node->data = data;
0051
0052     if (list->head == NULL)
0053     {
0054         list->head = node;
0055         list->tail = node;
0056         list->length = 1;
0057         return;
0058     }
0059
0060     tnode = list->head;
0061
0062     node->next = tnode;
0063     tnode->prev = node;
0064
0065     list->head = node;
0066     list->length++;
0067 }
0068
0069 static inline void
0070 pkgconf_node_insert_tail(pkgconf_node_t *node, void *data, pkgconf_list_t *list)
0071 {
0072     pkgconf_node_t *tnode;
0073
0074     node->data = data;
0075
0076     if (list->tail == NULL)
0077     {
0078         list->head = node;
0079         list->tail = node;
0080         list->length = 1;
0081         return;
0082     }
0083
0084     tnode = list->tail;
0085
0086     node->prev = tnode;
0087     tnode->next = node;
0088
0089     list->tail = node;
0090     list->length++;
0091 }
0092
0093 static inline void
0094 pkgconf_node_delete(pkgconf_node_t *node, pkgconf_list_t *list)
0095 {
0096     list->length--;
0097
0098     if (node->prev == NULL)
0099         list->head = node->next;
0100     else
0101         node->prev->next = node->next;
0102
0103     if (node->next == NULL)
0104         list->tail = node->prev;
0105     else
0106         node->next->prev = node->prev;
0107 }
0108
0109 #ifdef __cplusplus
0110 }
0111 #endif
0112
0113 #endif