/***********************************************************************

*                                                                      *

*               This software is part of the ast package               *

*          Copyright (c) 1985-2011 AT&T Intellectual Property          *

*                      and is licensed under the                       *

*                 Eclipse Public License, Version 1.0                  *

*                    by AT&T Intellectual Property                     *

*                                                                      *

*                A copy of the License is available at                 *

*          http://www.eclipse.org/org/documents/epl-v10.html           *

*         (with md5 checksum b35adb5213ca9657e911e9befb180842)         *

*                                                                      *

*              Information and Software Systems Research               *

*                            AT&T Research                             *

*                           Florham Park NJ                            *

*                                                                      *

*                 Glenn Fowler <gsf@research.att.com>                  *

*                  David Korn <dgk@research.att.com>                   *

*                   Phong Vo <kpv@research.att.com>                    *

*                                                                      *

***********************************************************************/

#pragma prototyped

/*

 * Glenn Fowler

 * AT&T Research

 *

 * hash table library

 */

#include "hashlib.h"

/*

 * free (remove) a hash table

 * can be called for partially constructed tables

 * scope covered table pointer is returned

 * root info freed when last reference freed

 */

Hash_table_t*

hashfree(register Hash_table_t* tab)

{

	register Hash_bucket_t**	sp;

	register Hash_bucket_t*		b;

	register Hash_bucket_t*		p;

	Hash_bucket_t**			sx;

	Hash_root_t*			rp;

	Hash_table_t*			tp;

	Hash_free_f			freevalue;

	Hash_free_f			freebucket;

	Hash_region_f			region;

	void*				handle;

	if (!tab) return(0);

	if (tab->table)

	{

		freebucket = 0;

		freevalue = 0;

		if (tab->root->local->free)

		{

			if (tab->root->flags & HASH_BUCKET) freebucket = tab->root->local->free;

			else freevalue = tab->root->local->free;

		}

		if (region = tab->root->local->region)

			handle = tab->root->local->handle;

		sx = &tab->table[tab->size];

		sp = &tab->table[0];

		while (sp < sx)

		{

			b = *sp++;

			while (b)

			{

				p = b;

				b = b->next;

				if (freebucket) (*freebucket)((char*)p);

				else if (freevalue && p->value) (*freevalue)(p->value);

				if (p->hash & HASH_FREENAME)

				{

					p->hash &= ~HASH_FREENAME;

					if (region) (*region)(handle, p->name, 0, 0);

					else free(p->name);

				}

				if (!(p->hash & HASH_KEEP))

				{

					if (region) (*region)(handle, p, 0, 0);

					else free(p);

				}

				else if (p->hash & HASH_HIDES)

				{

					p->hash &= ~HASH_HIDES;

					p->name = ((Hash_bucket_t*)p->name)->name;

				}

			}

		}

		if ((tab->flags & (HASH_RESIZE|HASH_STATIC)) != HASH_STATIC)

		{

			if (region) (*region)(handle, tab->table, 0, 0);

			else free(tab->table);

		}

	}

	else region = 0;

	if (tab->root)

	{

		if (!region)

		{

			/*

			 * remove from the table lists

			 */

			if ((tp = tab->root->references) != tab)

			{

				for (; tp; tp = tp->next)

					if (tp->next == tab)

					{

						tp->next = tab->next;

						break;

					}

			}

			else if (!(tab->root->references = tp->next))

			{

				if ((rp = hash_info.list) != tab->root)

				{

					for (; rp; rp = rp->next)

						if (rp->next == tab->root)

						{

							rp->next = tab->root->next;

							break;

						}

				}

				else hash_info.list = rp->next;

			}

		}

		if (!(tab->root->references))

		{

			if (tab->root->local)

				free(tab->root->local);

			if (region) (*region)(handle, tab->root, 0, 0);

			else free(tab->root);

		}

	}

	if (tp = tab->scope) tp->frozen--;

	if (region) (*region)(handle, tab, 0, 0);

	else free(tab);

	return(tp);

}