List_Remove.c
1.39 KB
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/*
* List_Remove.c --
*
* Source code for the List_Remove library procedure.
*
* Copyright 1988 Regents of the University of California
* Permission to use, copy, modify, and distribute this
* software and its documentation for any purpose and without
* fee is hereby granted, provided that the above copyright
* notice appear in all copies. The University of California
* makes no representations about the suitability of this
* software for any purpose. It is provided "as is" without
* express or implied warranty.
*/
#include <stdio.h>
#include "list.h"
/*
* ----------------------------------------------------------------------------
*
* List_Remove --
*
* Remove a list element from the list in which it is contained.
*
* Results:
* None.
*
* Side effects:
* The given structure is removed from its containing list.
*
* ----------------------------------------------------------------------------
*/
void
List_Remove(register List_Links* itemPtr)/* list element to remove */
{
if (itemPtr == (List_Links *) NIL || itemPtr == itemPtr->nextPtr
|| !itemPtr) {
List_Error("List_Remove: invalid item to remove.\n");
}
if (itemPtr->prevPtr->nextPtr != itemPtr ||
itemPtr->nextPtr->prevPtr != itemPtr) {
List_Error("List_Remove: item's pointers are invalid.\n");
}
itemPtr->prevPtr->nextPtr = itemPtr->nextPtr;
itemPtr->nextPtr->prevPtr = itemPtr->prevPtr;
}