1 /***********************************************************************
2 *                                                                      *
3 *               This software is part of the ast package               *
4 *          Copyright (c) 1985-2008 AT&T Intellectual Property          *
5 *                      and is licensed under the                       *
6 *                  Common Public License, Version 1.0                  *
7 *                    by AT&T Intellectual Property                     *
8 *                                                                      *
9 *                A copy of the License is available at                 *
10 *            http://www.opensource.org/licenses/cpl1.0.txt             *
11 *         (with md5 checksum 059e8cd6165cb4c31e351f2b69388fd9)         *
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 static const char id_hash[] = "\n@(#)$Id: hash (AT&T Research) 1996-08-11 $\0\n";
31 
32 #include "hashlib.h"
33 
34 Hash_info_t	hash_info = { 0 };
35 
36 /*
37  * create a new hash table
38  */
39 
40 Hash_table_t*
41 hashalloc(Hash_table_t* ref, ...)
42 {
43 	register Hash_table_t*	tab;
44 	register Hash_table_t*	ret = 0;
45 	register int		internal;
46 	int			n;
47 	va_list			ap;
48 	va_list			va[4];
49 	va_list*		vp = va;
50 	Hash_region_f		region = 0;
51 	void*			handle;
52 
53 	va_start(ap, ref);
54 
55 	/*
56 	 * check for HASH_region which must be first
57 	 */
58 
59 	n = va_arg(ap, int);
60 	if (!ref && n == HASH_region)
61 	{
62 		region = va_arg(ap, Hash_region_f);
63 		handle = va_arg(ap, void*);
64 		n = va_arg(ap, int);
65 		if (!(tab = (Hash_table_t*)(*region)(handle, NiL, sizeof(Hash_table_t), 0)))
66 			goto out;
67 		memset(tab, 0, sizeof(Hash_table_t));
68 	}
69 	else if (!(tab = newof(0, Hash_table_t, 1, 0)))
70 		goto out;
71 	tab->bucketsize = (sizeof(Hash_header_t) + sizeof(char*) - 1) / sizeof(char*);
72 	if (ref)
73 	{
74 		tab->flags = ref->flags & ~HASH_RESET;
75 		tab->root = ref->root;
76 		internal = HASH_INTERNAL;
77 	}
78 	else
79 	{
80 		if (region)
81 		{
82 			if (!(tab->root = (Hash_root_t*)(*region)(handle, NiL, sizeof(Hash_root_t), 0)))
83 				goto out;
84 			memset(tab->root, 0, sizeof(Hash_root_t));
85 		}
86 		else if (!(tab->root = newof(0, Hash_root_t, 1, 0)))
87 			goto out;
88 		if (!(tab->root->local = newof(0, Hash_local_t, 1, 0)))
89 			goto out;
90 		if (tab->root->local->region = region)
91 			tab->root->local->handle = handle;
92 		tab->root->meanchain = HASHMEANCHAIN;
93 		internal = 0;
94 	}
95 	tab->size = HASHMINSIZE;
96 	for (;;)
97 	{
98 		switch (n)
99 		{
100 		case HASH_alloc:
101 			if (ref) goto out;
102 			tab->root->local->alloc = va_arg(ap, Hash_alloc_f);
103 			break;
104 		case HASH_bucketsize:
105 			n = (va_arg(ap, int) + sizeof(char*) - 1) / sizeof(char*);
106 			if (n > UCHAR_MAX) goto out;
107 			if (n > tab->bucketsize) tab->bucketsize = n;
108 			break;
109 		case HASH_clear:
110 			tab->flags &= ~(va_arg(ap, int) & ~internal);
111 			break;
112 		case HASH_compare:
113 			if (ref) goto out;
114 			tab->root->local->compare = va_arg(ap, Hash_compare_f);
115 			break;
116 		case HASH_free:
117 			if (ref) goto out;
118 			tab->root->local->free = va_arg(ap, Hash_free_f);
119 			break;
120 		case HASH_hash:
121 			if (ref) goto out;
122 			tab->root->local->hash = va_arg(ap, Hash_hash_f);
123 			break;
124 		case HASH_meanchain:
125 			if (ref) goto out;
126 			tab->root->meanchain = va_arg(ap, int);
127 			break;
128 		case HASH_name:
129 			tab->name = va_arg(ap, char*);
130 			break;
131 		case HASH_namesize:
132 			if (ref) goto out;
133 			tab->root->namesize = va_arg(ap, int);
134 			break;
135 		case HASH_region:
136 			goto out;
137 		case HASH_set:
138 			tab->flags |= (va_arg(ap, int) & ~internal);
139 			break;
140 		case HASH_size:
141 			tab->size = va_arg(ap, int);
142 			if (tab->size & (tab->size - 1)) tab->flags |= HASH_FIXED;
143 			break;
144 		case HASH_table:
145 			tab->table = va_arg(ap, Hash_bucket_t**);
146 			tab->flags |= HASH_STATIC;
147 			break;
148 		case HASH_va_list:
149 			if (vp < &va[elementsof(va)])
150 			{
151 				va_copy(*vp, ap);
152 				vp++;
153 			}
154 			va_copy(ap, va_listval(va_arg(ap, va_listarg)));
155 			break;
156 		case 0:
157 			if (vp > va)
158 			{
159 				vp--;
160 				va_copy(ap, *vp);
161 				break;
162 			}
163 			if (tab->flags & HASH_SCOPE)
164 			{
165 				if (!(tab->scope = ref)) goto out;
166 				ref->frozen++;
167 			}
168 			if (!tab->table)
169 			{
170 				if (region)
171 				{
172 					if (!(tab->table = (Hash_bucket_t**)(*region)(handle, NiL, sizeof(Hash_bucket_t*) * tab->size, 0)))
173 						goto out;
174 					memset(tab->table, 0, sizeof(Hash_bucket_t*) * tab->size);
175 				}
176 				else if (!(tab->table = newof(0, Hash_bucket_t*, tab->size, 0))) goto out;
177 			}
178 			if (!ref)
179 			{
180 				tab->root->flags = tab->flags & HASH_INTERNAL;
181 				tab->root->next = hash_info.list;
182 				hash_info.list = tab->root;
183 			}
184 			if (!region)
185 			{
186 				tab->next = tab->root->references;
187 				tab->root->references = tab;
188 			}
189 			ret = tab;
190 			goto out;
191 		default:
192 			goto out;
193 		}
194 		n = va_arg(ap, int);
195 	}
196  out:
197 	va_end(ap);
198 	if (!ret) hashfree(tab);
199 	return(ret);
200 }
201