1 files changed, 729 insertions, 0 deletions
diff --git a/Source/lib/utils/linked_list.c b/Source/lib/utils/linked_list.c
new file mode 100644
index 000000000..407065d24
--- /dev/null
+++ b/Source/lib/utils/linked_list.c
@@ -0,0 +1,729 @@
+/**
+ * @file linked_list.c
+ *
+ * @brief Implementation of linked_list_t.
+ *
+ */
+
+/*
+ * Copyright (C) 2005 Jan Hutter, Martin Willi
+ * Hochschule fuer Technik Rapperswil
+ *
+ * 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.  See <http://www.fsf.org/copyleft/gpl.txt>.
+ *
+ * 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.
+ */
+
+#include <stdlib.h>
+
+#include "linked_list.h"
+
+#include <utils/allocator.h>
+
+
+
+typedef struct linked_list_element_t linked_list_element_t;
+
+/**
+ * @brief Element in a linked list.
+ *
+ * This element holds a pointer to the value it represents.
+ */
+struct linked_list_element_t {
+
+	/**
+	 * Value of a list item.
+	 */
+	void *value;
+
+	/**
+	 * Previous list element.
+	 * 
+	 * NULL if first element in list.
+	 */
+	linked_list_element_t *previous;
+	
+	/**
+	 * Next list element.
+	 * 
+	 * NULL if last element in list.
+	 */
+	linked_list_element_t *next;
+
+	/**
+	 * Destroys a linked_list_element object.
+	 *
+	 * @param linked_list_element_t 	calling object
+	 */
+	void (*destroy) (linked_list_element_t *this);
+};
+
+/**
+ * Implementation of linked_list_element_t.destroy.
+ */
+static void linked_list_element_destroy(linked_list_element_t *this)
+{
+	allocator_free(this);
+}
+
+/**
+ * @brief Creates an empty linked list object.
+ *
+ * @warning Only the pointer to the value is stored.
+ * 
+ * @param[in] value 		value of item to be set
+ * @return 					linked_list_element_t object
+ */
+
+linked_list_element_t *linked_list_element_create(void *value)
+{
+	linked_list_element_t *this = allocator_alloc_thing(linked_list_element_t);
+
+	this->destroy = linked_list_element_destroy;
+
+	this->previous=NULL;
+	this->next=NULL;
+	this->value = value;
+
+	return (this);
+}
+
+
+typedef struct private_linked_list_t private_linked_list_t;
+
+/**
+ * Private data of a linked_list_t object.
+ *
+ */
+struct private_linked_list_t {
+	/**
+	 * Public part of linked list.
+	 */
+	linked_list_t public;
+
+	/**
+	 * Number of items in the list.
+	 */
+	int count;
+
+	/**
+	 * First element in list.
+	 * NULL if no elements in list.
+	 */
+	linked_list_element_t *first;
+	
+	/**
+	 * Last element in list.
+	 * NULL if no elements in list.
+	 */
+	linked_list_element_t *last;
+};
+
+
+typedef struct private_iterator_t private_iterator_t;
+
+/**
+ * Private variables and functions of linked list iterator.
+ */
+struct private_iterator_t {
+	/**
+	 * Public part of linked list iterator.
+	 */
+	iterator_t public;
+
+	/**
+	 * Associated linked list.
+	 */
+	private_linked_list_t * list;
+
+	/**
+	 * Current element of the iterator.
+	 */
+	linked_list_element_t *current;
+
+	/**
+	 * Direction of iterator.
+	 */
+	bool forward;
+};
+
+/**
+ * Implementation of iterator_t.has_next.
+ */
+static bool iterate(private_iterator_t *this, void** value)
+{
+	if (this->list->count == 0)
+	{
+		return FALSE;
+	}
+	if (this->current == NULL)
+	{
+		this->current = (this->forward) ? this->list->first : this->list->last;
+		*value = this->current->value;
+		return TRUE;
+	}
+	if (this->forward)
+	{
+		if (this->current->next == NULL)
+		{
+			return FALSE;
+		}
+		this->current = this->current->next;
+		*value = this->current->value;
+		return TRUE;
+	}
+	/* backward */
+	if (this->current->previous == NULL)
+	{
+		return FALSE;
+	}
+	this->current = this->current->previous;
+	*value = this->current->value;
+	return TRUE;
+}
+
+/**
+ * Implementation of iterator_t.has_next.
+ */
+static bool iterator_has_next(private_iterator_t *this)
+{
+	if (this->list->count == 0)
+	{
+		return FALSE;
+	}
+	if (this->current == NULL)
+	{
+		this->current = (this->forward) ? this->list->first : this->list->last;
+		return TRUE;
+	}
+	if (this->forward)
+	{
+		if (this->current->next == NULL)
+		{
+			return FALSE;
+		}
+		this->current = this->current->next;
+		return TRUE;
+	}
+	/* backward */
+	if (this->current->previous == NULL)
+	{
+		return FALSE;
+	}
+	this->current = this->current->previous;
+	return TRUE;
+}
+
+/**
+ * Implementation of iterator_t.current.
+ */
+static status_t iterator_current(private_iterator_t *this, void **value)
+{
+	if (this->current == NULL)
+	{
+		return NOT_FOUND;
+	}
+	*value = this->current->value;
+	return SUCCESS;
+}
+
+/**
+ * Implementation of iterator_t.reset.
+ */
+static void iterator_reset(private_iterator_t *this)
+{
+	this->current = NULL;
+}
+
+/**
+ * Implementation of iterator_t.remove.
+ */
+static status_t remove(private_iterator_t *this)
+{
+	linked_list_element_t *new_current;
+
+	if (this->current == NULL)
+	{
+		return NOT_FOUND;
+	}
+
+	if (this->list->count == 0)
+	{
+		return NOT_FOUND;
+	}
+	/* find out the new iterator position */
+	if (this->current->previous != NULL)
+	{
+		new_current = this->current->previous;
+	}
+	else if (this->current->next != NULL)
+	{
+		new_current = this->current->next;
+	}
+	else
+	{
+		new_current = NULL;
+	}
+
+	/* now delete the entry :-) */
+	if (this->current->previous == NULL)
+	{
+		if (this->current->next == NULL)
+		{
+			this->list->first = NULL;
+			this->list->last = NULL;
+		}
+		else
+		{
+			this->current->next->previous = NULL;
+			this->list->first = this->current->next;
+		}
+	}
+	else if (this->current->next == NULL)
+	{
+		this->current->previous->next = NULL;
+		this->list->last = this->current->previous;
+	}
+	else
+	{
+		this->current->previous->next = this->current->next;
+		this->current->next->previous = this->current->previous;
+	}
+
+	this->list->count--;
+	this->current->destroy(this->current);
+	/* set the new iterator position */
+	this->current = new_current;
+	return SUCCESS;
+}
+
+/**
+ * Implementation of iterator_t.insert_before.
+ */
+static void insert_before(private_iterator_t * iterator, void *item)
+{
+	if (iterator->current == NULL)
+	{
+		iterator->list->public.insert_first(&(iterator->list->public), item);
+	}
+
+	linked_list_element_t *element =(linked_list_element_t *) linked_list_element_create(item);
+
+	if (iterator->current->previous == NULL)
+	{
+		iterator->current->previous = element;
+		element->next = iterator->current;
+		iterator->list->first = element;
+	}
+	else
+	{
+		iterator->current->previous->next = element;
+		element->previous = iterator->current->previous;
+		iterator->current->previous = element;
+		element->next = iterator->current;
+	}
+
+	iterator->list->count++;
+}
+
+/**
+ * Implementation of iterator_t.replace.
+ */
+static status_t replace (private_iterator_t *this, void **old_item, void *new_item)
+{
+	if (this->current == NULL)
+	{
+		return NOT_FOUND;
+	}
+	if (old_item != NULL)
+	{
+		*old_item = this->current->value;
+	}
+	this->current->value = new_item;
+	
+	return SUCCESS;
+}
+
+/**
+ * Implementation of iterator_t.insert_after.
+ */
+static void insert_after(private_iterator_t * iterator, void *item)
+{
+	if (iterator->current == NULL)
+	{
+		iterator->list->public.insert_first(&(iterator->list->public),item);
+		return;
+	}
+
+	linked_list_element_t *element =(linked_list_element_t *) linked_list_element_create(item);
+
+	if (iterator->current->next == NULL)
+	{
+		iterator->current->next = element;
+		element->previous = iterator->current;
+		iterator->list->last = element;
+	}
+	else
+	{
+		iterator->current->next->previous = element;
+		element->next = iterator->current->next;
+		iterator->current->next = element;
+		element->previous = iterator->current;
+	}
+	iterator->list->count++;
+}
+
+/**
+ * Implementation of iterator_t.destroy.
+ */
+static void iterator_destroy(private_iterator_t *this)
+{
+	allocator_free(this);
+}
+
+/**
+ * Implementation of linked_list_t.get_count.
+ */
+static int get_count(private_linked_list_t *this)
+{
+	return this->count;
+}
+
+/**
+ * Implementation of linked_list_t.call_on_items.
+ */
+static void call_on_items(private_linked_list_t *this, void(*func)(void*))
+{
+	iterator_t *iterator;
+	void *item;
+	
+	iterator = this->public.create_iterator(&(this->public),TRUE);
+	
+	while (iterator->has_next(iterator))
+	{
+		iterator->current(iterator, &item);
+		(*func)(item);
+	}
+	iterator->destroy(iterator);
+}
+
+/**
+ * Implementation of linked_list_t.insert_first.
+ */
+static void insert_first(private_linked_list_t *this, void *item)
+{
+	linked_list_element_t *element;
+
+	element =(linked_list_element_t *) linked_list_element_create(item);
+
+	if (this->count == 0)
+	{
+		/* first entry in list */
+		this->first = element;
+		this->last = element;
+		element->previous = NULL;
+		element->next = NULL;
+	}
+	else
+	{
+		linked_list_element_t *old_first_element = this->first;
+		element->next = old_first_element;
+		element->previous = NULL;
+		old_first_element->previous = element;
+		this->first = element;
+	}
+
+	this->count++;
+}
+
+/**
+ * Implementation of linked_list_t.remove_first.
+ */
+static status_t remove_first(private_linked_list_t *this, void **item)
+{
+	if (this->count == 0)
+	{
+		return NOT_FOUND;
+	}
+
+	linked_list_element_t *element = this->first;
+
+	if (element->next != NULL)
+	{
+		element->next->previous = NULL;
+	}
+	this->first = element->next;
+
+	if (item != NULL)
+	{
+		*item = element->value;
+	}
+
+	this->count--;
+
+	element->destroy(element);
+	
+	return SUCCESS;
+}
+
+/**
+ * Implementation of linked_list_t.get_first.
+ */
+static status_t get_first(private_linked_list_t *this, void **item)
+{
+	if (this->count == 0)
+	{
+		return NOT_FOUND;
+	}
+
+	*item = this->first->value;
+
+	return SUCCESS;
+}
+
+/**
+ * Implementation of linked_list_t.insert_last.
+ */
+static void insert_last(private_linked_list_t *this, void *item)
+{
+	linked_list_element_t *element = (linked_list_element_t *) linked_list_element_create(item);
+
+	if (this->count == 0)
+	{
+		/* first entry in list */
+		this->first = element;
+		this->last = element;
+		element->previous = NULL;
+		element->next = NULL;
+	}
+	else
+	{
+
+		linked_list_element_t *old_last_element = this->last;
+		element->previous = old_last_element;
+		element->next = NULL;
+		old_last_element->next = element;
+		this->last = element;
+	}
+
+	this->count++;
+}
+
+/**
+ * Implementation of linked_list_t.remove_last.
+ */
+static status_t remove_last(private_linked_list_t *this, void **item)
+{
+	if (this->count == 0)
+	{
+		return NOT_FOUND;
+	}
+
+	linked_list_element_t *element = this->last;
+
+	if (element->previous != NULL)
+	{
+		element->previous->next = NULL;
+	}
+	this->last = element->previous;
+
+	if (item != NULL)
+	{
+		*item = element->value;
+	}
+
+	this->count--;
+
+	element->destroy(element);
+	
+	return SUCCESS;
+}
+
+/**
+ * Implementation of linked_list_t.insert_at_position.
+ */
+static status_t insert_at_position (private_linked_list_t *this,size_t position, void *item)
+{
+	linked_list_element_t *current_element;
+	int i;
+	
+	if (this->count <= position)
+	{
+		return INVALID_ARG;
+	}
+	
+	current_element =  this->first;
+	
+	for (i = 0; i < position;i++)
+	{
+		current_element = current_element->next;
+	}
+
+	if (current_element == NULL)
+	{
+		this->public.insert_last(&(this->public),item);
+		return SUCCESS;
+	}
+
+	linked_list_element_t *element =(linked_list_element_t *) linked_list_element_create(item);
+
+
+	if (current_element->previous == NULL)
+	{
+		current_element->previous = element;
+		element->next = current_element;
+		this->first = element;
+	}
+	else
+	{
+		current_element->previous->next = element;
+		element->previous = current_element->previous;
+		current_element->previous = element;
+		element->next = current_element;
+	}
+
+
+	this->count++;
+	return SUCCESS;
+}
+	
+/**
+ * Implementation of linked_list_t.remove_at_position.
+ */
+static status_t remove_at_position (private_linked_list_t *this,size_t position, void **item)
+{
+	iterator_t *iterator;
+	int i;
+
+	if (this->count <= position)
+	{
+		return INVALID_ARG;
+	}
+	
+	iterator = this->public.create_iterator(&(this->public),TRUE);
+	
+	iterator->has_next(iterator);
+	for (i = 0; i < position;i++)
+	{
+		iterator->has_next(iterator);
+	}
+	iterator->current(iterator,item);
+	iterator->remove(iterator);
+	iterator->destroy(iterator);
+
+	return SUCCESS;
+}
+
+/**
+ * Implementation of linked_list_t.get_at_position.
+ */
+static status_t get_at_position (private_linked_list_t *this,size_t position, void **item)
+{
+	int i;
+	iterator_t *iterator;
+	status_t status;
+	if (this->count <= position)
+	{
+		return INVALID_ARG;
+	}
+
+	iterator = this->public.create_iterator(&(this->public),TRUE);
+	
+	iterator->has_next(iterator);
+	for (i = 0; i < position;i++)
+	{
+		iterator->has_next(iterator);
+	}
+	status = iterator->current(iterator,item);
+	iterator->destroy(iterator);
+	return status;
+}
+
+/**
+ * Implementation of linked_list_t.get_last.
+ */
+static status_t get_last(private_linked_list_t *this, void **item)
+{
+	if (this->count == 0)
+	{
+		return NOT_FOUND;
+	}
+
+	*item = this->last->value;
+
+	return SUCCESS;
+}
+
+/**
+ * Implementation of linked_list_t.create_iterator.
+ */
+static iterator_t *create_iterator (private_linked_list_t *linked_list,bool forward)
+{
+	private_iterator_t *this = allocator_alloc_thing(private_iterator_t);
+
+	this->public.iterate = (bool (*) (iterator_t *this, void **value)) iterate;
+	this->public.has_next = (bool (*) (iterator_t *this)) iterator_has_next;
+	this->public.current = (status_t (*) (iterator_t *this, void **value)) iterator_current;
+	this->public.insert_before = (void (*) (iterator_t *this, void *item)) insert_before;
+	this->public.insert_after = (void (*) (iterator_t *this, void *item)) insert_after;
+	this->public.replace = (status_t (*) (iterator_t *, void **, void *)) replace;
+	this->public.remove = (status_t (*) (iterator_t *this)) remove;
+	this->public.reset = (void (*) (iterator_t *this)) iterator_reset;
+	this->public.destroy = (void (*) (iterator_t *this)) iterator_destroy;
+
+	this->forward = forward;
+	this->current = NULL;
+	this->list = linked_list;
+
+	return &(this->public);
+}
+
+/**
+ * Implementation of linked_list_t.destroy.
+ */
+static void linked_list_destroy(private_linked_list_t *this)
+{
+	void * value;
+	/* Remove all list items before destroying list */
+	while (this->public.remove_first(&(this->public),&value) != NOT_FOUND)
+	{
+		/* values are not destroyed so memory leaks are possible
+		 * if list is not empty when deleting */
+	}
+	allocator_free(this);
+}
+
+/*
+ * Described in header.
+ */
+linked_list_t *linked_list_create()
+{
+	private_linked_list_t *this = allocator_alloc_thing(private_linked_list_t);
+
+	this->public.get_count = (int (*) (linked_list_t *)) get_count;
+	this->public.create_iterator = (iterator_t * (*) (linked_list_t *,bool )) create_iterator;
+	this->public.call_on_items = (void (*) (linked_list_t *, void(*func)(void*)))call_on_items;
+	this->public.get_first = (status_t (*) (linked_list_t *, void **item)) get_first;
+	this->public.get_last = (status_t (*) (linked_list_t *, void **item)) get_last;
+	this->public.insert_first = (void (*) (linked_list_t *, void *item)) insert_first;
+	this->public.insert_last = (void (*) (linked_list_t *, void *item)) insert_last;
+	this->public.remove_first = (status_t (*) (linked_list_t *, void **item)) remove_first;
+	this->public.remove_last = (status_t (*) (linked_list_t *, void **item)) remove_last;
+	this->public.insert_at_position =(status_t (*) (linked_list_t *,size_t, void *)) insert_at_position;
+	this->public.remove_at_position =(status_t (*) (linked_list_t *,size_t, void **)) remove_at_position;
+	this->public.get_at_position =(status_t (*) (linked_list_t *,size_t, void **)) get_at_position;
+	
+	this->public.destroy = (void (*) (linked_list_t *)) linked_list_destroy;
+
+	this->count = 0;
+	this->first = NULL;
+	this->last = NULL;
+
+	return (&(this->public));
+}