12

list.c

@@ -1,136 +1,228 @@
-
 #include <assert.h>
 #include <string.h>
 
 #include "util.h"
 #include "list.h"
 
-
 void
 list_init(list *l)
 {
-	assert(l);
+    assert(l);
-	memset(l, 0, sizeof(*l));
+    memset(l, 0, sizeof(*l));
 }
 
 static inline list_node *
 list_node_orphan(list_node *li)
 {
-	li->next = NULL;
+    li->next = NULL;
-	li->prev = NULL;
+    li->prev = NULL;
-	return li;
+    return li;
 }
 
-//NOTE: Можем ли мы расчитывать на то, что node->next валидно после вызова list_free_cb???
 void
 list_clear(list *l, list_free_cb cb)
 {
-	assert(l);
+    assert(l);
-	// <YOURCODE>
+    list_node *current = l->head;
+    while (current != NULL) {
+        list_node *next = current->next;
+        if (cb) {
+            cb(current);
+        }
+        current = next;
+    }
+    l->head = NULL;
+    l->tail = NULL;
 }
 
 void
 list_push_front(list *l, list_node *item)
 {
-	assert(l && item);
+    assert(l && item);
-	// <YOURCODE>
+    item->prev = NULL;
+    item->next = l->head;
+    
+    if (l->head != NULL) {
+        l->head->prev = item;
+    } else {
+        l->tail = item;
+    }
+    l->head = item;
 }
 
 void
 list_push_back(list *l, list_node *item)
 {
-	assert(l && item);
+    assert(l && item);
-	// <YOURCODE>
+    item->next = NULL;
+    item->prev = l->tail;
+    
+    if (l->tail != NULL) {
+        l->tail->next = item;
+    } else {
+        l->head = item;
+    }
+    l->tail = item;
 }
 
 list_node *
 list_first(list *l)
 {
-	assert(l);
+    assert(l);
-	return l->head;
+    return l->head;
 }
 
 list_node *
 list_last(list *l)
 {
-	assert(l);
+    assert(l);
-	return l->tail;
+    return l->tail;
 }
 
 size_t
 list_len(list *l)
 {
-	assert(l);
+    assert(l);
-	// <YOURCODE>
+    size_t count = 0;
-	return 0;
+    list_node *current = l->head;
+    while (current != NULL) {
+        count++;
+        current = current->next;
+    }
+    return count;
 }
 
 list_node *
 list_get(list *l, int idx)
 {
-	assert(l);
+    assert(l);
-	// <YOURCODE>
+    if (idx < 0) return NULL;
-	return NULL;
+    
+    list_node *current = l->head;
+    int i = 0;
+    while (current != NULL && i < idx) {
+        current = current->next;
+        i++;
+    }
+    return current;
 }
 
 void
 list_insert(list *l, list_node *item, int idx)
 {
-	assert(l && item);
+    assert(l && item);
-	// <YOURCODE>
+    if (idx == 0) {
+        list_push_front(l, item);
+        return;
+    }
+    
+    list_node *current = list_get(l, idx);
+    if (current == NULL) {
+        list_push_back(l, item);
+        return;
+    }
+    
+    item->next = current;
+    item->prev = current->prev;
+    current->prev->next = item;
+    current->prev = item;
 }
 
 list_node *
 list_pop_front(list *l)
 {
-	assert(l);
+    assert(l);
-	// <YOURCODE>
+    if (l->head == NULL) return NULL;
-	return NULL;
+    
+    list_node *front = l->head;
+    l->head = front->next;
+    if (l->head != NULL) {
+        l->head->prev = NULL;
+    } else {
+        l->tail = NULL;
+    }
+    return list_node_orphan(front);
 }
 
 list_node *
 list_pop_back(list *l)
 {
-	assert(l);
+    assert(l);
-	// <YOURCODE>
+    if (l->tail == NULL) return NULL;
-	return NULL;
+    
+    list_node *back = l->tail;
+    l->tail = back->prev;
+    if (l->tail != NULL) {
+        l->tail->next = NULL;
+    } else {
+        l->head = NULL;
+    }
+    return list_node_orphan(back);
 }
 
 int
 list_index(list *l, list_node *n)
 {
-	assert(l && n);
+    assert(l && n);
-	list_node *tmp;
+    list_node *tmp;
-	int i = 0;
+    int i = 0;
-	for (tmp = l->head; tmp != NULL; tmp = tmp->next) {
+    for (tmp = l->head; tmp != NULL; tmp = tmp->next) {
-		if (tmp == n)
+        if (tmp == n)
-			return i;
+            return i;
-		i++;
+        i++;
-	}
+    }
-	return -1;
+    return -1;
 }
 
 list_node *
 list_remove(list *l, int idx)
 {
-	assert(l);
+    assert(l);
-	// <YOURCODE>
+    if (idx < 0) return NULL;
-	return NULL;
+    
+    list_node *node = list_get(l, idx);
+    if (node == NULL) return NULL;
+    
+    if (node->prev != NULL) {
+        node->prev->next = node->next;
+    } else {
+        l->head = node->next;
+    }
+    
+    if (node->next != NULL) {
+        node->next->prev = node->prev;
+    } else {
+        l->tail = node->prev;
+    }
+    
+    return list_node_orphan(node);
 }
 
 void
 list_reverse(list *l)
 {
-	assert(l);
+    assert(l);
-	// <YOURCODE>
+    list_node *current = l->head;
+    list_node *temp = NULL;
+    
+    while (current != NULL) {
+        temp = current->prev;
+        current->prev = current->next;
+        current->next = temp;
+        current = current->prev;
+    }
+    
+    if (temp != NULL) {
+        l->tail = l->head;
+        l->head = temp->prev;
+    }
 }
 
-
 void
 list_pass(list *l, list_pass_cb cb, void *opaq)
 {
-	struct list_node *iter;
+    struct list_node *iter;
-	list_for_each(iter, l) {
+    list_for_each(iter, l) {
-		cb(iter, opaq);
+        cb(iter, opaq);
-	}
+    }
-}
+}