MCL/sf/app/videoeditor: comparison videoeditorengine/h263decoder/src/dlist.cpp

equal deleted inserted replaced

--1:000000000000
+:951a5db380a0
+/*
+* Copyright (c) 2010 Ixonos Plc.
+* All rights reserved.
+* This component and the accompanying materials are made available
+* under the terms of the "Eclipse Public License v1.0"
+* which accompanies this distribution, and is available
+* at the URL "http://www.eclipse.org/legal/epl-v10.html".
+*
+* Initial Contributors:
+* Nokia Corporation - Initial contribution
+*
+* Contributors:
+* Ixonos Plc
+*
+* Description:
+* Doubly linked list module.
+*
+*/
+/*
+* dlist.c
+*
+*
+*
+* Project:
+*    Mobile Videophone Demonstrator
+*    H.263 Video Decoder
+*
+* Contains:
+*    This module contains generic list handling functions for doubly linked
+*    lists, i.e. one can use the same set of functions regardless of the type
+*    of list items.
+*    The list item type has a constraint that it must begin with the skeleton
+*    of a list item (see the definition of DLST_ITEM_SKELETON in dlist.h).
+*
+*    The prefix ddlst is used in common names defined in this module.
+*
+*
+*
+*/
+#include "dlist.h"
+#ifndef NULL
+#define NULL 0
+#endif
+/*
+* dlstClose
+*
+*
+* Parameters:
+*    list                       a pointer to a list
+*
+* Function:
+*    This function deinitializes the given list. Notice that no dynamic
+*    allocation for the list is done. This function must be called when
+*    the list is no longer used.
+*
+* Returns:
+*    >= 0 if the function was successful
+*    < 0  indicating an error
+*
+*/
+int dlstClose(dlst_t *list)
+{
+list->head = list->tail = list->curr = NULL;
+list->numItems = 0;
+return 0;
+}
+/*
+* dlstRemove
+*
+*
+* Parameters:
+*    list                       a pointer to a list
+*    item                       used to return a pointer to the removed
+*                               list item
+*
+* Function:
+*    This function removes an item from the list. Notice that no copying of
+*    contents of the given item is done, i.e. only the pointer to the item
+*    is used.
+*
+*    If there are no items left in the list, NULL will be returned in
+*    the item parameter.
+*
+* Returns:
+*    >= 0 if the function was successful
+*    < 0  indicating an error
+*
+*/
+int dlstRemove(dlst_t *list, void **item)
+{
+if (list->curr) {
+dlstListItem_t
+*curr = list->curr,
+*prev = (dlstListItem_t *) (list->curr->prev),
+*next = (dlstListItem_t *) (list->curr->next);
+*item = (void *) curr;
+if (prev)
+prev->next = curr->next;
+else
+list->head = (dlstListItem_t *) curr->next;
+if (next)
+next->prev = curr->prev;
+curr->next = NULL;
+curr->prev = NULL;
+if (curr == list->tail) {
+list->tail = prev;
+list->curr = prev;
+}
+else
+list->curr = next;
+list->numItems--;
+}
+else
+*item = NULL;
+return 0;
+}
+/*
+* dlstOpen
+*
+*
+* Parameters:
+*    list                       a pointer to a list
+*
+* Function:
+*    This function initializes the given list. Notice that no dynamic
+*    allocation for the list is done. This function must be called before
+*    the list is used.
+*
+* Returns:
+*    >= 0 if the function was successful
+*    < 0  indicating an error
+*
+*/
+int dlstOpen(dlst_t *list)
+{
+list->head = list->tail = list->curr = NULL;
+list->numItems = 0;
+return 0;
+}
+/*
+* dlstHead
+*
+*
+* Parameters:
+*    list                       a pointer to a dlst list
+*    item                       used to return a pointer to the head item
+*                               of the list
+*
+* Function:
+*    This function sets the current access point to the head of the list and
+*    returns a pointer to the head item. Notice that no copying of
+*    contents of the given item is done, i.e. only the pointer to the item
+*    is used.
+*
+*    If there are no items left in the list, NULL will be returned in
+*    the item parameter.
+*
+* Returns:
+*    >= 0 if the function was successful
+*    < 0  indicating an error
+*
+*/
+int dlstHead(dlst_t *list, void **item)
+{
+if (list->head)
+*item = (void *) list->head;
+else
+*item = NULL;
+list->curr = list->head;
+return 0;
+}
+/*
+* dlstTail
+*
+*
+* Parameters:
+*    list                       a pointer to a dlst list
+*
+* Function:
+*    This function sets the current access point to the tail of the list
+*    enabling the item addition to the end of the list.
+*
+* Returns:
+*    >= 0 if the function was successful
+*    < 0  indicating an error
+*
+*/
+int dlstTail(dlst_t *list, void **item)
+{
+if (list->tail)
+*item = (void *) list->tail;
+else
+*item = NULL;
+list->curr = list->tail;
+return 0;
+}
+/*
+* dlstNext
+*
+*
+* Parameters:
+*    list                       a pointer to a dlst list
+*    item                       used to return a pointer to the next item
+*                               of the list
+*
+* Function:
+*    This function sets the current access point to the next item of the list
+*    and returns a pointer to the item. Notice that no copying of
+*    contents of the given item is done, i.e. only the pointer to the item
+*    is used.
+*
+*    If there are no items left in the list, NULL will be returned in
+*    the item parameter and the current access point shall be left as it is.
+*
+* Returns:
+*    >= 0 if the function was successful
+*    < 0  indicating an error
+*
+*/
+int dlstNext(dlst_t *list, void **item)
+{
+if (list->curr && list->curr->next) {
+list->curr = (dlstListItem_t *) (list->curr->next);
+*item = (void *) list->curr;
+}
+else
+*item = NULL;
+return 0;
+}
+int dlstPrev(dlst_t *list, void **item)
+{
+if (list->curr && list->curr->prev) {
+list->curr = (dlstListItem_t *) (list->curr->prev);
+*item = (void *) list->curr;
+}
+else
+*item = NULL;
+return 0;
+}
+int dlstCurr(dlst_t *list, void **item)
+{
+*item = (void *) list->curr;
+return 0;
+}
+int dlstNextExists(dlst_t *list)
+{
+return (list->curr && list->curr->next) ? 1 : 0;
+}
+/*
+* dlstAdd
+*
+*
+* Parameters:
+*    list                       a pointer to a dlst list
+*    item                       an item to add to the list
+*
+* Function:
+*    This function adds an item into the list. Notice that no copying of
+*    contents of the given item is done, i.e. only the pointer to the item
+*    is used.
+*
+* Returns:
+*    >= 0 if the function was successful
+*    < 0  indicating an error
+*
+*/
+int dlstAddBeforeCurr(dlst_t *list, void *item)
+{
+dlstListItem_t
+*curr, *prev, *listItem = (dlstListItem_t *) item;
+if (list->curr) {
+curr = (dlstListItem_t *) list->curr,
+prev = (dlstListItem_t *) list->curr->prev;
+if (prev)
+prev->next = item;
+else
+list->head = (dlstListItem_t *) item;
+listItem->prev = prev;
+curr->prev = item;
+listItem->next = curr;
+list->curr = (dlstListItem_t *) item;
+}
+else {
+list->head = list->tail = list->curr = (dlstListItem_t *) item;
+listItem->next = NULL;
+listItem->prev = NULL;
+}
+list->numItems++;
+return 0;
+}
+int dlstAddAfterCurr(dlst_t *list, void *item)
+{
+dlstListItem_t
+*curr, *next, *listItem = (dlstListItem_t *) item;
+if (list->curr) {
+curr = list->curr,
+next = (dlstListItem_t *) (list->curr->next);
+curr->next = item;
+listItem->prev = curr;
+if (next)
+next->prev = item;
+else
+list->tail = (dlstListItem_t *) item;
+listItem->next = next;
+list->curr = (dlstListItem_t *) item;
+}
+else {
+list->head = list->tail = list->curr = (dlstListItem_t *) item;
+listItem->next = NULL;
+listItem->prev = NULL;
+}
+list->numItems++;
+return 0;
+}
+// End of File