src/java.desktop/unix/native/libawt_xawt/awt/list.c - platform/libcore - Git at Google

 /*
  * Copyright (c) 1999, 2018, Oracle and/or its affiliates. All rights reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
  * This code is free software; you can redistribute it and/or modify it
  * under the terms of the GNU General Public License version 2 only, as
  * published by the Free Software Foundation.  Oracle designates this
  * particular file as subject to the "Classpath" exception as provided
  * by Oracle in the LICENSE file that accompanied this code.
  *
  * This code 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
  * version 2 for more details (a copy is included in the LICENSE file that
  * accompanied this code).
  *
  * You should have received a copy of the GNU General Public License version
  * 2 along with this work; if not, write to the Free Software Foundation,
  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
  *
  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
  * or visit www.oracle.com if you need additional information or have any
  * questions.
  */
 /** ------------------------------------------------------------------------
         This file contains routines for manipulating generic lists.
         Lists are implemented with a "harness".  In other words, each
         node in the list consists of two pointers, one to the data item
         and one to the next node in the list.  The head of the list is
         the same struct as each node, but the "item" ptr is used to point
         to the current member of the list (used by the first_in_list and
         next_in_list functions).

  This file is available under and governed by the GNU General Public
  License version 2 only, as published by the Free Software Foundation.
  However, the following notice accompanied the original version of this
  file:

 Copyright 1994 Hewlett-Packard Co.
 Copyright 1996, 1998  The Open Group

 Permission to use, copy, modify, distribute, and sell this software and its
 documentation for any purpose is hereby granted without fee, provided that
 the above copyright notice appear in all copies and that both that
 copyright notice and this permission notice appear in supporting
 documentation.

 The above copyright notice and this permission notice shall be included
 in all copies or substantial portions of the Software.

 THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
 OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
 MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
 IN NO EVENT SHALL THE OPEN GROUP BE LIABLE FOR ANY CLAIM, DAMAGES OR
 OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
 ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
 OTHER DEALINGS IN THE SOFTWARE.

 Except as contained in this notice, the name of The Open Group shall
 not be used in advertising or otherwise to promote the sale, use or
 other dealings in this Software without prior written authorization
 from The Open Group.

   ----------------------------------------------------------------------- **/

 #include <stdio.h>
 #include <stdlib.h>

 #include "list.h"


 /** ------------------------------------------------------------------------
         Sets the pointers of the specified list to NULL.
     --------------------------------------------------------------------- **/
 void zero_list(list_ptr lp)
 {
     lp->next = NULL;
     lp->ptr.item = NULL;
 }


 /** ------------------------------------------------------------------------
         Adds item to the list pointed to by lp.  Finds the end of the
         list, then mallocs a new list node onto the end of the list.
         The item pointer in the new node is set to "item" passed in,
         and the next pointer in the new node is set to NULL.
         Returns 1 if successful, 0 if the malloc failed.
     -------------------------------------------------------------------- **/
 int add_to_list(list_ptr lp, void *item)
 {
     while (lp->next) {
         lp = lp->next;
     }
     if ((lp->next = (list_ptr) malloc( sizeof( list_item))) == NULL) {

         return 0;
     }
     lp->next->ptr.item = item;
     lp->next->next = NULL;

     return 1;
 }


 /** ------------------------------------------------------------------------
         Creates a new list and sets its pointers to NULL.
         Returns a pointer to the new list.
     -------------------------------------------------------------------- **/
 list_ptr new_list (void)
 {
     list_ptr lp;

     if ((lp = (list_ptr) malloc( sizeof( list_item)))) {
         lp->next = NULL;
         lp->ptr.item = NULL;
     }

     return lp;
 }


 /** ------------------------------------------------------------------------
         Creates a new list head, pointing to the same list as the one
         passed in.  If start_at_curr is TRUE, the new list's first item
         is the "current" item (as set by calls to first/next_in_list()).
         If start_at_curr is FALSE, the first item in the new list is the
         same as the first item in the old list.  In either case, the
         curr pointer in the new list is the same as in the old list.
         Returns a pointer to the new list head.
     -------------------------------------------------------------------- **/
 list_ptr dup_list_head(list_ptr lp, int start_at_curr)
 {
     list_ptr new_listp;

     if ((new_listp = (list_ptr) malloc( sizeof( list_item))) == NULL) {

         return (list_ptr)NULL;
     }
     new_listp->next = start_at_curr ? lp->ptr.curr : lp->next;
     new_listp->ptr.curr = lp->ptr.curr;

     return new_listp;
 }


 /** ------------------------------------------------------------------------
         Returns the number of items in the list.
     -------------------------------------------------------------------- **/
 unsigned int list_length(list_ptr lp)
 {
     unsigned int count = 0;

     while (lp->next) {
         count++;
         lp = lp->next;
     }

     return count;
 }


 /** ------------------------------------------------------------------------
         Scans thru list, looking for a node whose ptr.item is equal to
         the "item" passed in.  "Equal" here means the same address - no
         attempt is made to match equivalent values stored in different
         locations.  If a match is found, that node is deleted from the
         list.  Storage for the node is freed, but not for the item itself.
         Returns a pointer to the item, so the caller can free it if it
         so desires.  If a match is not found, returns NULL.
     -------------------------------------------------------------------- **/
 void *delete_from_list(list_ptr lp, void *item)
 {
     list_ptr new_next;

     while (lp->next) {
         if (lp->next->ptr.item == item) {
             new_next = lp->next->next;
             free (lp->next);
             lp->next = new_next;

             return item;
         }
         lp = lp->next;
     }

     return NULL;
 }


 /** ------------------------------------------------------------------------
         Deletes each node in the list *except the head*.  This allows
         the deletion of lists where the head is not malloced or created
         with new_list().  If free_items is true, each item pointed to
         from the node is freed, in addition to the node itself.
     -------------------------------------------------------------------- **/
 void delete_list(list_ptr lp, int free_items)
 {
     list_ptr del_node;
     void *item;

     while (lp->next) {
         del_node = lp->next;
         item = del_node->ptr.item;
         lp->next = del_node->next;
         free (del_node);
         if (free_items) {
             free( item);
         }
     }
 }

 void delete_list_destroying(list_ptr lp, void destructor(void *item))
 {
     list_ptr del_node;
     void *item;

     while (lp->next) {
         del_node = lp->next;
         item = del_node->ptr.item;
         lp->next = del_node->next;
         free( del_node);
         if (destructor) {
             destructor( item);
         }
     }
 }


 /** ------------------------------------------------------------------------
         Returns a ptr to the first *item* (not list node) in the list.
         Sets the list head node's curr ptr to the first node in the list.
         Returns NULL if the list is empty.
     -------------------------------------------------------------------- **/
 void * first_in_list(list_ptr lp)
 {
     if (! lp) {

         return NULL;
     }
     lp->ptr.curr = lp->next;

     return lp->ptr.curr ? lp->ptr.curr->ptr.item : NULL;
 }

 /** ------------------------------------------------------------------------
         Returns a ptr to the next *item* (not list node) in the list.
         Sets the list head node's curr ptr to the next node in the list.
         first_in_list must have been called prior.
         Returns NULL if no next item.
     -------------------------------------------------------------------- **/
 void * next_in_list(list_ptr lp)
 {
     if (! lp) {

         return NULL;
     }
     if (lp->ptr.curr) {
         lp->ptr.curr = lp->ptr.curr->next;
     }

     return lp->ptr.curr ? lp->ptr.curr->ptr.item : NULL;
 }

 int list_is_empty(list_ptr lp)
 {
     return (lp == NULL || lp->next == NULL);
 }
	/*
	* Copyright (c) 1999, 2018, Oracle and/or its affiliates. All rights reserved.
	* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
	*
	* This code is free software; you can redistribute it and/or modify it
	* under the terms of the GNU General Public License version 2 only, as
	* published by the Free Software Foundation. Oracle designates this
	* particular file as subject to the "Classpath" exception as provided
	* by Oracle in the LICENSE file that accompanied this code.
	*
	* This code 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
	* version 2 for more details (a copy is included in the LICENSE file that
	* accompanied this code).
	*
	* You should have received a copy of the GNU General Public License version
	* 2 along with this work; if not, write to the Free Software Foundation,
	* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
	*
	* Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
	* or visit www.oracle.com if you need additional information or have any
	* questions.
	*/
	/** ------------------------------------------------------------------------
	This file contains routines for manipulating generic lists.
	Lists are implemented with a "harness". In other words, each
	node in the list consists of two pointers, one to the data item
	and one to the next node in the list. The head of the list is
	the same struct as each node, but the "item" ptr is used to point
	to the current member of the list (used by the first_in_list and
	next_in_list functions).

	This file is available under and governed by the GNU General Public
	License version 2 only, as published by the Free Software Foundation.
	However, the following notice accompanied the original version of this
	file:

	Copyright 1994 Hewlett-Packard Co.
	Copyright 1996, 1998 The Open Group

	Permission to use, copy, modify, distribute, and sell this software and its
	documentation for any purpose is hereby granted without fee, provided that
	the above copyright notice appear in all copies and that both that
	copyright notice and this permission notice appear in supporting
	documentation.

	The above copyright notice and this permission notice shall be included
	in all copies or substantial portions of the Software.

	THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
	OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
	MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
	IN NO EVENT SHALL THE OPEN GROUP BE LIABLE FOR ANY CLAIM, DAMAGES OR
	OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
	ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
	OTHER DEALINGS IN THE SOFTWARE.

	Except as contained in this notice, the name of The Open Group shall
	not be used in advertising or otherwise to promote the sale, use or
	other dealings in this Software without prior written authorization
	from The Open Group.

	----------------------------------------------------------------------- **/

	#include <stdio.h>
	#include <stdlib.h>

	#include "list.h"


	/** ------------------------------------------------------------------------
	Sets the pointers of the specified list to NULL.
	--------------------------------------------------------------------- **/
	void zero_list(list_ptr lp)
	{
	lp->next = NULL;
	lp->ptr.item = NULL;
	}


	/** ------------------------------------------------------------------------
	Adds item to the list pointed to by lp. Finds the end of the
	list, then mallocs a new list node onto the end of the list.
	The item pointer in the new node is set to "item" passed in,
	and the next pointer in the new node is set to NULL.
	Returns 1 if successful, 0 if the malloc failed.
	-------------------------------------------------------------------- **/
	int add_to_list(list_ptr lp, void *item)
	{
	while (lp->next) {
	lp = lp->next;
	}
	if ((lp->next = (list_ptr) malloc( sizeof( list_item))) == NULL) {

	return 0;
	}
	lp->next->ptr.item = item;
	lp->next->next = NULL;

	return 1;
	}


	/** ------------------------------------------------------------------------
	Creates a new list and sets its pointers to NULL.
	Returns a pointer to the new list.
	-------------------------------------------------------------------- **/
	list_ptr new_list (void)
	{
	list_ptr lp;

	if ((lp = (list_ptr) malloc( sizeof( list_item)))) {
	lp->next = NULL;
	lp->ptr.item = NULL;
	}

	return lp;
	}


	/** ------------------------------------------------------------------------
	Creates a new list head, pointing to the same list as the one
	passed in. If start_at_curr is TRUE, the new list's first item
	is the "current" item (as set by calls to first/next_in_list()).
	If start_at_curr is FALSE, the first item in the new list is the
	same as the first item in the old list. In either case, the
	curr pointer in the new list is the same as in the old list.
	Returns a pointer to the new list head.
	-------------------------------------------------------------------- **/
	list_ptr dup_list_head(list_ptr lp, int start_at_curr)
	{
	list_ptr new_listp;

	if ((new_listp = (list_ptr) malloc( sizeof( list_item))) == NULL) {

	return (list_ptr)NULL;
	}
	new_listp->next = start_at_curr ? lp->ptr.curr : lp->next;
	new_listp->ptr.curr = lp->ptr.curr;

	return new_listp;
	}


	/** ------------------------------------------------------------------------
	Returns the number of items in the list.
	-------------------------------------------------------------------- **/
	unsigned int list_length(list_ptr lp)
	{
	unsigned int count = 0;

	while (lp->next) {
	count++;
	lp = lp->next;
	}

	return count;
	}


	/** ------------------------------------------------------------------------
	Scans thru list, looking for a node whose ptr.item is equal to
	the "item" passed in. "Equal" here means the same address - no
	attempt is made to match equivalent values stored in different
	locations. If a match is found, that node is deleted from the
	list. Storage for the node is freed, but not for the item itself.
	Returns a pointer to the item, so the caller can free it if it
	so desires. If a match is not found, returns NULL.
	-------------------------------------------------------------------- **/
	void delete_from_list(list_ptr lp, void item)
	{
	list_ptr new_next;

	while (lp->next) {
	if (lp->next->ptr.item == item) {
	new_next = lp->next->next;
	free (lp->next);
	lp->next = new_next;

	return item;
	}
	lp = lp->next;
	}

	return NULL;
	}


	/** ------------------------------------------------------------------------
	Deletes each node in the list except the head. This allows
	the deletion of lists where the head is not malloced or created
	with new_list(). If free_items is true, each item pointed to
	from the node is freed, in addition to the node itself.
	-------------------------------------------------------------------- **/
	void delete_list(list_ptr lp, int free_items)
	{
	list_ptr del_node;
	void *item;

	while (lp->next) {
	del_node = lp->next;
	item = del_node->ptr.item;
	lp->next = del_node->next;
	free (del_node);
	if (free_items) {
	free( item);
	}
	}
	}

	void delete_list_destroying(list_ptr lp, void destructor(void *item))
	{
	list_ptr del_node;
	void *item;

	while (lp->next) {
	del_node = lp->next;
	item = del_node->ptr.item;
	lp->next = del_node->next;
	free( del_node);
	if (destructor) {
	destructor( item);
	}
	}
	}


	/** ------------------------------------------------------------------------
	Returns a ptr to the first item (not list node) in the list.
	Sets the list head node's curr ptr to the first node in the list.
	Returns NULL if the list is empty.
	-------------------------------------------------------------------- **/
	void * first_in_list(list_ptr lp)
	{
	if (! lp) {

	return NULL;
	}
	lp->ptr.curr = lp->next;

	return lp->ptr.curr ? lp->ptr.curr->ptr.item : NULL;
	}

	/** ------------------------------------------------------------------------
	Returns a ptr to the next item (not list node) in the list.
	Sets the list head node's curr ptr to the next node in the list.
	first_in_list must have been called prior.
	Returns NULL if no next item.
	-------------------------------------------------------------------- **/
	void * next_in_list(list_ptr lp)
	{
	if (! lp) {

	return NULL;
	}
	if (lp->ptr.curr) {
	lp->ptr.curr = lp->ptr.curr->next;
	}

	return lp->ptr.curr ? lp->ptr.curr->ptr.item : NULL;
	}

	int list_is_empty(list_ptr lp)
	{
	return (lp == NULL \|\| lp->next == NULL);
	}