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/* Copyright (c) 2007-2009, UNINETT AS */
/* See LICENSE for licensing information. */
#include "list.h"
#include <stdlib.h>
#include <string.h>
/* Private helper functions. */
static void list_free_helper_(struct list *list, int free_data_flag) {
struct list_node *node, *next;
if (!list)
return;
for (node = list->first; node; node = next) {
if (free_data_flag)
free(node->data);
next = node->next;
free(node);
}
free(list);
}
/* Public functions. */
/* allocates and initialises list structure; returns NULL if malloc fails */
struct list *list_create(void) {
struct list *list = malloc(sizeof(struct list));
if (list)
memset(list, 0, sizeof(struct list));
return list;
}
/* frees all memory associated with the list
note that the data pointed at from each node is also freed
use list_free() to free only the memory used by the list itself */
void list_destroy(struct list *list) {
list_free_helper_(list, 1);
}
/* frees the meory used by the list itself
note that the data pointed at from each node is not freed
use list_destroy() to free all the data associated with the list */
void list_free(struct list *list) {
list_free_helper_(list, 0);
}
/* 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;
list->count++;
return 1;
}
/* insert entry at front of the list; returns 1 if ok, 0 if malloc fails */
int list_push_front(struct list *list, void *data) {
struct list_node *node;
node = malloc(sizeof(struct list_node));
if (!node)
return 0;
node->data = data;
node->next = list->first;
if (!list->first)
list->last = node;
list->first = node;
list->count++;
return 1;
}
/* removes first entry from list and returns data */
void *list_shift(struct list *list) {
struct list_node *node;
void *data;
if (!list || !list->first)
return NULL;
node = list->first;
list->first = node->next;
if (!list->first)
list->last = NULL;
data = node->data;
free(node);
list->count--;
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);
list->count--;
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);
list->count--;
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;
}
/* returns number of nodes */
uint32_t list_count(struct list *list) {
return list->count;
}
/* Local Variables: */
/* c-file-style: "stroustrup" */
/* End: */
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