297 lines
8.6 KiB
C
297 lines
8.6 KiB
C
/* adlist.c - A generic doubly linked list implementation
|
|
*
|
|
* Copyright (c) 2006-2010, Salvatore Sanfilippo <antirez at gmail dot com>
|
|
* All rights reserved.
|
|
*
|
|
* Redistribution and use in source and binary forms, with or without
|
|
* modification, are permitted provided that the following conditions are met:
|
|
*
|
|
* * Redistributions of source code must retain the above copyright notice,
|
|
* this list of conditions and the following disclaimer.
|
|
* * Redistributions in binary form must reproduce the above copyright
|
|
* notice, this list of conditions and the following disclaimer in the
|
|
* documentation and/or other materials provided with the distribution.
|
|
* * Neither the name of Redis nor the names of its contributors may be used
|
|
* to endorse or promote products derived from this software without
|
|
* specific prior written permission.
|
|
*
|
|
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
|
|
* AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
|
|
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
|
|
* ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
|
|
* LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
|
|
* CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
|
|
* SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
|
|
* INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
|
|
* CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
|
|
* ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
|
|
* POSSIBILITY OF SUCH DAMAGE.
|
|
*/
|
|
|
|
|
|
#include <stdlib.h>
|
|
#include "adlist.h"
|
|
#include "zmalloc.h"
|
|
|
|
/* Create a new list. The created list can be freed with
|
|
* AlFreeList(), but private value of every node need to be freed
|
|
* by the user before to call AlFreeList().
|
|
*
|
|
* On error, NULL is returned. Otherwise the pointer to the new list. */
|
|
list *listCreate(void)
|
|
{
|
|
struct list *list;
|
|
|
|
if ((list = zmalloc(sizeof(*list))) == NULL)
|
|
return NULL;
|
|
list->head = list->tail = NULL;
|
|
list->len = 0;
|
|
list->dup = NULL;
|
|
list->free = NULL;
|
|
list->match = NULL;
|
|
return list;
|
|
}
|
|
|
|
/* Free the whole list.
|
|
*
|
|
* This function can't fail. */
|
|
void listRelease(list *list)
|
|
{
|
|
unsigned int len;
|
|
listNode *current, *next;
|
|
|
|
current = list->head;
|
|
len = list->len;
|
|
while(len--) {
|
|
next = current->next;
|
|
if (list->free) list->free(current->value);
|
|
zfree(current);
|
|
current = next;
|
|
}
|
|
zfree(list);
|
|
}
|
|
|
|
/* Add a new node to the list, to head, contaning the specified 'value'
|
|
* pointer as value.
|
|
*
|
|
* On error, NULL is returned and no operation is performed (i.e. the
|
|
* list remains unaltered).
|
|
* On success the 'list' pointer you pass to the function is returned. */
|
|
list *listAddNodeHead(list *list, void *value)
|
|
{
|
|
listNode *node;
|
|
|
|
if ((node = zmalloc(sizeof(*node))) == NULL)
|
|
return NULL;
|
|
node->value = value;
|
|
if (list->len == 0) {
|
|
list->head = list->tail = node;
|
|
node->prev = node->next = NULL;
|
|
} else {
|
|
node->prev = NULL;
|
|
node->next = list->head;
|
|
list->head->prev = node;
|
|
list->head = node;
|
|
}
|
|
list->len++;
|
|
return list;
|
|
}
|
|
|
|
/* Add a new node to the list, to tail, contaning the specified 'value'
|
|
* pointer as value.
|
|
*
|
|
* On error, NULL is returned and no operation is performed (i.e. the
|
|
* list remains unaltered).
|
|
* On success the 'list' pointer you pass to the function is returned. */
|
|
list *listAddNodeTail(list *list, void *value)
|
|
{
|
|
listNode *node;
|
|
|
|
if ((node = zmalloc(sizeof(*node))) == NULL)
|
|
return NULL;
|
|
node->value = value;
|
|
if (list->len == 0) {
|
|
list->head = list->tail = node;
|
|
node->prev = node->next = NULL;
|
|
} else {
|
|
node->prev = list->tail;
|
|
node->next = NULL;
|
|
list->tail->next = node;
|
|
list->tail = node;
|
|
}
|
|
list->len++;
|
|
return list;
|
|
}
|
|
|
|
/* Remove the specified node from the specified list.
|
|
* It's up to the caller to free the private value of the node.
|
|
*
|
|
* This function can't fail. */
|
|
void listDelNode(list *list, listNode *node)
|
|
{
|
|
if (node->prev)
|
|
node->prev->next = node->next;
|
|
else
|
|
list->head = node->next;
|
|
if (node->next)
|
|
node->next->prev = node->prev;
|
|
else
|
|
list->tail = node->prev;
|
|
if (list->free) list->free(node->value);
|
|
zfree(node);
|
|
list->len--;
|
|
}
|
|
|
|
/* Returns a list iterator 'iter'. After the initialization every
|
|
* call to listNext() will return the next element of the list.
|
|
*
|
|
* This function can't fail. */
|
|
listIter *listGetIterator(list *list, int direction)
|
|
{
|
|
listIter *iter;
|
|
|
|
if ((iter = zmalloc(sizeof(*iter))) == NULL) return NULL;
|
|
if (direction == AL_START_HEAD)
|
|
iter->next = list->head;
|
|
else
|
|
iter->next = list->tail;
|
|
iter->direction = direction;
|
|
return iter;
|
|
}
|
|
|
|
/* Release the iterator memory */
|
|
void listReleaseIterator(listIter *iter) {
|
|
zfree(iter);
|
|
}
|
|
|
|
/* Create an iterator in the list private iterator structure */
|
|
void listRewind(list *list, listIter *li) {
|
|
li->next = list->head;
|
|
li->direction = AL_START_HEAD;
|
|
}
|
|
|
|
void listRewindTail(list *list, listIter *li) {
|
|
li->next = list->tail;
|
|
li->direction = AL_START_TAIL;
|
|
}
|
|
|
|
/* Return the next element of an iterator.
|
|
* It's valid to remove the currently returned element using
|
|
* listDelNode(), but not to remove other elements.
|
|
*
|
|
* The function returns a pointer to the next element of the list,
|
|
* or NULL if there are no more elements, so the classical usage patter
|
|
* is:
|
|
*
|
|
* iter = listGetItarotr(list,<direction>);
|
|
* while ((node = listNextIterator(iter)) != NULL) {
|
|
* DoSomethingWith(listNodeValue(node));
|
|
* }
|
|
*
|
|
* */
|
|
listNode *listNext(listIter *iter)
|
|
{
|
|
listNode *current = iter->next;
|
|
|
|
if (current != NULL) {
|
|
if (iter->direction == AL_START_HEAD)
|
|
iter->next = current->next;
|
|
else
|
|
iter->next = current->prev;
|
|
}
|
|
return current;
|
|
}
|
|
|
|
/* Duplicate the whole list. On out of memory NULL is returned.
|
|
* On success a copy of the original list is returned.
|
|
*
|
|
* The 'Dup' method set with listSetDupMethod() function is used
|
|
* to copy the node value. Otherwise the same pointer value of
|
|
* the original node is used as value of the copied node.
|
|
*
|
|
* The original list both on success or error is never modified. */
|
|
list *listDup(list *orig)
|
|
{
|
|
list *copy;
|
|
listIter *iter;
|
|
listNode *node;
|
|
|
|
if ((copy = listCreate()) == NULL)
|
|
return NULL;
|
|
copy->dup = orig->dup;
|
|
copy->free = orig->free;
|
|
copy->match = orig->match;
|
|
iter = listGetIterator(orig, AL_START_HEAD);
|
|
while((node = listNext(iter)) != NULL) {
|
|
void *value;
|
|
|
|
if (copy->dup) {
|
|
value = copy->dup(node->value);
|
|
if (value == NULL) {
|
|
listRelease(copy);
|
|
listReleaseIterator(iter);
|
|
return NULL;
|
|
}
|
|
} else
|
|
value = node->value;
|
|
if (listAddNodeTail(copy, value) == NULL) {
|
|
listRelease(copy);
|
|
listReleaseIterator(iter);
|
|
return NULL;
|
|
}
|
|
}
|
|
listReleaseIterator(iter);
|
|
return copy;
|
|
}
|
|
|
|
/* Search the list for a node matching a given key.
|
|
* The match is performed using the 'match' method
|
|
* set with listSetMatchMethod(). If no 'match' method
|
|
* is set, the 'value' pointer of every node is directly
|
|
* compared with the 'key' pointer.
|
|
*
|
|
* On success the first matching node pointer is returned
|
|
* (search starts from head). If no matching node exists
|
|
* NULL is returned. */
|
|
listNode *listSearchKey(list *list, void *key)
|
|
{
|
|
listIter *iter;
|
|
listNode *node;
|
|
|
|
iter = listGetIterator(list, AL_START_HEAD);
|
|
while((node = listNext(iter)) != NULL) {
|
|
if (list->match) {
|
|
if (list->match(node->value, key)) {
|
|
listReleaseIterator(iter);
|
|
return node;
|
|
}
|
|
} else {
|
|
if (key == node->value) {
|
|
listReleaseIterator(iter);
|
|
return node;
|
|
}
|
|
}
|
|
}
|
|
listReleaseIterator(iter);
|
|
return NULL;
|
|
}
|
|
|
|
/* Return the element at the specified zero-based index
|
|
* where 0 is the head, 1 is the element next to head
|
|
* and so on. Negative integers are used in order to count
|
|
* from the tail, -1 is the last element, -2 the penultimante
|
|
* and so on. If the index is out of range NULL is returned. */
|
|
listNode *listIndex(list *list, int index) {
|
|
listNode *n;
|
|
|
|
if (index < 0) {
|
|
index = (-index)-1;
|
|
n = list->tail;
|
|
while(index-- && n) n = n->prev;
|
|
} else {
|
|
n = list->head;
|
|
while(index-- && n) n = n->next;
|
|
}
|
|
return n;
|
|
}
|