add fifo/lifo

fifo_lifo.c

@@ -0,0 +1,81 @@
+/*
+ * fifo_lifo.c - simple FIFO/LIFO
+ *
+ * Copyright 2013 Edward V. Emelianoff <eddy@sao.ru>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston,
+ * MA 02110-1301, USA.
+ */
+
+#include "usefull_macros.h"
+
+/**
+ * @brief list_push_tail - push data into the tail of a stack (like FIFO)
+ * @param lst (io) - list
+ * @param v (i)    - data to push
+ * @return pointer to just pused node or NULL in case of error
+ */
+List *list_push_tail(List **lst, void *v){
+	List *node;
+	if(!lst) return NULL;
+	if((node = MALLOC(List, 1)) == NULL)
+		return NULL; // allocation error
+	node->data = v; // insert data
+	if(!*lst){
+		*lst = node;
+    }else{
+        (*lst)->last->next = node;
+    }
+	(*lst)->last = node;
+	return node;
+}
+
+/**
+ * @brief list_push - push data into the head of a stack (like LIFO)
+ * @param lst (io) - list
+ * @param v (i)    - data to push
+ * @return pointer to just pused node
+ */
+List *list_push(List **lst, void *v){
+	List *node;
+	if(!lst) return NULL;
+	if((node = MALLOC(List, 1)) == NULL)
+		return NULL; // allocation error
+	node->data = v; // insert data
+	if(!*lst){
+		*lst = node;
+		(*lst)->last = node;
+		return node;
+	}
+	node->next = *lst;
+	node->last = (*lst)->last;
+	*lst = node;
+	return node;
+}
+
+/**
+ * @brief list_pop - get data from head of list. Don't forget to FREE list data after `pop`
+ * @param lst (io) - list
+ * @return data from lst head
+ */
+void *list_pop(List **lst){
+	void *ret;
+	List *node = *lst;
+	if(!lst || !*lst) return NULL;
+	ret = (*lst)->data;
+	*lst = (*lst)->next;
+	FREE(node);
+	return ret;
+}