X-Git-Url: https://pd.if.org/git/?p=lice;a=blobdiff_plain;f=list.c;fp=list.c;h=e5804474b5330e439faaa9134b53df606ee27075;hp=0000000000000000000000000000000000000000;hb=686688990cde8ecd8d9423fde7f88b6ac6ac8a40;hpb=e8938573442eb3f5f550420ff3a0eb703730c1a3

diff --git a/list.c b/list.c
new file mode 100644
index 0000000..e580447
--- /dev/null
+++ b/list.c
@@ -0,0 +1,140 @@
+#include "util.h"
+#include "list.h"
+
+typedef struct list_node_s list_node_t;
+
+struct list_node_s {
+    void        *element;
+    list_node_t *next;
+    list_node_t *prev;
+};
+
+struct list_iterator_s {
+    list_node_t *pointer;
+};
+
+list_t *list_create(void) {
+    list_t *list = memory_allocate(sizeof(list_t));
+    list->length = 0;
+    list->head   = NULL;
+    list->tail   = NULL;
+
+    return list;
+}
+
+void *list_node_create(void *element) {
+    list_node_t *node = memory_allocate(sizeof(list_node_t));
+    node->element     = element;
+    node->next        = NULL;
+    node->prev        = NULL;
+    return node;
+}
+
+void list_push(list_t *list, void *element) {
+    list_node_t *node = list_node_create(element);
+    if (!list->head)
+        list->head = node;
+    else {
+        list->tail->next = node;
+        node->prev       = list->tail;
+    }
+    list->tail = node;
+    list->length++;
+}
+
+void *list_pop(list_t *list) {
+    if (!list->head)
+        return NULL;
+    void *element = list->tail->element;
+    list->tail = list->tail->prev;
+    if (list->tail)
+        list->tail->next = NULL;
+    else
+        list->head = NULL;
+    list->length--;
+    return element;
+}
+
+void *list_shift(list_t *list) {
+    if (!list->head)
+        return NULL;
+    void *element = list->head->element;
+    list->head = list->head->next;
+    if (list->head)
+        list->head->prev = NULL;
+    else
+        list->tail = NULL;
+    list->length--;
+    return element;
+}
+
+int list_length(list_t *list) {
+    return list->length;
+}
+
+list_iterator_t *list_iterator(list_t *list) {
+    list_iterator_t *iter = memory_allocate(sizeof(list_iterator_t));
+    iter->pointer         = list->head;
+    return iter;
+}
+
+void *list_iterator_next(list_iterator_t *iter) {
+    void *ret;
+
+    if (!iter->pointer)
+        return NULL;
+
+    ret           = iter->pointer->element;
+    iter->pointer = iter->pointer->next;
+
+    return ret;
+}
+
+bool list_iterator_end(list_iterator_t *iter) {
+    return !iter->pointer;
+}
+
+static void list_shiftify(list_t *list, void *element) {
+    list_node_t *node = list_node_create(element);
+    node->next = list->head;
+    if (list->head)
+        list->head->prev = node;
+    list->head = node;
+    if (!list->tail)
+        list->tail = node;
+    list->length++;
+}
+
+list_t *list_reverse(list_t *list) {
+    list_t *ret = list_create();
+    for (list_iterator_t *it = list_iterator(list); !list_iterator_end(it); )
+        list_shiftify(ret, list_iterator_next(it));
+    return ret;
+}
+
+void *list_tail(list_t *list) {
+    if (!list->head)
+        return NULL;
+
+    list_node_t *node = list->head;
+    while (node->next)
+        node = node->next;
+
+    return node->element;
+}
+
+void *list_head(list_t *list) {
+    return list->head->element;
+}
+
+void list_empty(list_t *list) {
+    list->length = 0;
+    list->head   = NULL;
+    list->tail   = NULL;
+}
+
+list_t *list_default(void *item) {
+    list_t *list = list_create();
+    list_push(list, item);
+    return list;
+}