1/***********************************************************************
2*                                                                      *
3*               This software is part of the ast package               *
4*          Copyright (c) 1985-2011 AT&T Intellectual Property          *
5*                      and is licensed under the                       *
6*                 Eclipse Public License, Version 1.0                  *
7*                    by AT&T Intellectual Property                     *
8*                                                                      *
9*                A copy of the License is available at                 *
10*          http://www.eclipse.org/org/documents/epl-v10.html           *
11*         (with md5 checksum b35adb5213ca9657e911e9befb180842)         *
12*                                                                      *
13*              Information and Software Systems Research               *
14*                            AT&T Research                             *
15*                           Florham Park NJ                            *
16*                                                                      *
17*                 Glenn Fowler <gsf@research.att.com>                  *
18*                  David Korn <dgk@research.att.com>                   *
19*                   Phong Vo <kpv@research.att.com>                    *
20*                                                                      *
21***********************************************************************/
22#pragma prototyped
23/*
24 * Glenn Fowler
25 * AT&T Research
26 *
27 * hash table library
28 */
29
30#include "hashlib.h"
31
32/*
33 * free (remove) a hash table
34 * can be called for partially constructed tables
35 * scope covered table pointer is returned
36 * root info freed when last reference freed
37 */
38
39Hash_table_t*
40hashfree(register Hash_table_t* tab)
41{
42	register Hash_bucket_t**	sp;
43	register Hash_bucket_t*		b;
44	register Hash_bucket_t*		p;
45	Hash_bucket_t**			sx;
46	Hash_root_t*			rp;
47	Hash_table_t*			tp;
48	Hash_free_f			freevalue;
49	Hash_free_f			freebucket;
50	Hash_region_f			region;
51	void*				handle;
52
53	if (!tab) return(0);
54	if (tab->table)
55	{
56		freebucket = 0;
57		freevalue = 0;
58		if (tab->root->local->free)
59		{
60			if (tab->root->flags & HASH_BUCKET) freebucket = tab->root->local->free;
61			else freevalue = tab->root->local->free;
62		}
63		if (region = tab->root->local->region)
64			handle = tab->root->local->handle;
65		sx = &tab->table[tab->size];
66		sp = &tab->table[0];
67		while (sp < sx)
68		{
69			b = *sp++;
70			while (b)
71			{
72				p = b;
73				b = b->next;
74				if (freebucket) (*freebucket)((char*)p);
75				else if (freevalue && p->value) (*freevalue)(p->value);
76				if (p->hash & HASH_FREENAME)
77				{
78					p->hash &= ~HASH_FREENAME;
79					if (region) (*region)(handle, p->name, 0, 0);
80					else free(p->name);
81				}
82				if (!(p->hash & HASH_KEEP))
83				{
84					if (region) (*region)(handle, p, 0, 0);
85					else free(p);
86				}
87				else if (p->hash & HASH_HIDES)
88				{
89					p->hash &= ~HASH_HIDES;
90					p->name = ((Hash_bucket_t*)p->name)->name;
91				}
92			}
93		}
94		if ((tab->flags & (HASH_RESIZE|HASH_STATIC)) != HASH_STATIC)
95		{
96			if (region) (*region)(handle, tab->table, 0, 0);
97			else free(tab->table);
98		}
99	}
100	else region = 0;
101	if (tab->root)
102	{
103		if (!region)
104		{
105			/*
106			 * remove from the table lists
107			 */
108
109			if ((tp = tab->root->references) != tab)
110			{
111				for (; tp; tp = tp->next)
112					if (tp->next == tab)
113					{
114						tp->next = tab->next;
115						break;
116					}
117			}
118			else if (!(tab->root->references = tp->next))
119			{
120				if ((rp = hash_info.list) != tab->root)
121				{
122					for (; rp; rp = rp->next)
123						if (rp->next == tab->root)
124						{
125							rp->next = tab->root->next;
126							break;
127						}
128				}
129				else hash_info.list = rp->next;
130			}
131		}
132		if (!(tab->root->references))
133		{
134			if (tab->root->local)
135				free(tab->root->local);
136			if (region) (*region)(handle, tab->root, 0, 0);
137			else free(tab->root);
138		}
139	}
140	if (tp = tab->scope) tp->frozen--;
141	if (region) (*region)(handle, tab, 0, 0);
142	else free(tab);
143	return(tp);
144}
145