ReactOS 0.4.15-dev-7906-g1b85a5f
hash.c
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1/* hash.c
2
3 Routines for manipulating hash tables... */
4
5/*
6 * Copyright (c) 1995, 1996, 1997, 1998 The Internet Software Consortium.
7 * All rights reserved.
8 *
9 * Redistribution and use in source and binary forms, with or without
10 * modification, are permitted provided that the following conditions
11 * are met:
12 *
13 * 1. Redistributions of source code must retain the above copyright
14 * notice, this list of conditions and the following disclaimer.
15 * 2. Redistributions in binary form must reproduce the above copyright
16 * notice, this list of conditions and the following disclaimer in the
17 * documentation and/or other materials provided with the distribution.
18 * 3. Neither the name of The Internet Software Consortium nor the names
19 * of its contributors may be used to endorse or promote products derived
20 * from this software without specific prior written permission.
21 *
22 * THIS SOFTWARE IS PROVIDED BY THE INTERNET SOFTWARE CONSORTIUM AND
23 * CONTRIBUTORS ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES,
24 * INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
25 * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
26 * DISCLAIMED. IN NO EVENT SHALL THE INTERNET SOFTWARE CONSORTIUM OR
27 * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
28 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
29 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
30 * USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
31 * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
32 * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
33 * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
34 * SUCH DAMAGE.
35 *
36 * This software has been written for the Internet Software Consortium
37 * by Ted Lemon <mellon@fugue.com> in cooperation with Vixie
38 * Enterprises. To learn more about the Internet Software Consortium,
39 * see ``http://www.vix.com/isc''. To learn more about Vixie
40 * Enterprises, see ``http://www.vix.com''.
41 */
42
43#define lint
44#ifndef lint
45static char copyright[] =
46"$Id: hash.c,v 1.9.2.3 1999/04/09 17:39:41 mellon Exp $ Copyright (c) 1995, 1996, 1997, 1998 The Internet Software Consortium. All rights reserved.\n";
47#endif /* not lint */
48
49#include <rosdhcp.h>
50
51static __inline int do_hash PROTO ((unsigned char *, int, int));
52
54{
56 if (!rv)
57 return rv;
58 memset (&rv -> buckets [0], 0,
59 DEFAULT_HASH_SIZE * sizeof (struct hash_bucket *));
60 return rv;
61}
62
63static __inline int do_hash (name, len, size)
64 unsigned char *name;
65 int len;
66 int size;
67{
68 register int accum = 0;
69 register unsigned char *s = name;
70 int i = len;
71 while (i--) {
72 /* Add the character in... */
73 accum += *s++;
74 /* Add carry back in... */
75 while (accum > 255) {
76 accum = (accum & 255) + (accum >> 8);
77 }
78 }
79 return accum % size;
80}
81
83 struct hash_table *table;
84 int len;
85 unsigned char *name;
86 unsigned char *pointer;
87{
88 int hashno;
89 struct hash_bucket *bp;
90
91 if (!table)
92 return;
93 if (!len)
94 len = strlen ((char *)name);
95
96 hashno = do_hash (name, len, table -> hash_count);
97 bp = new_hash_bucket ();
98
99 if (!bp) {
100 warn ("Can't add %s to hash table.", name);
101 return;
102 }
103 bp -> name = name;
104 bp -> value = pointer;
105 bp -> next = table -> buckets [hashno];
106 bp -> len = len;
107 table -> buckets [hashno] = bp;
108}
109
111 struct hash_table *table;
112 int len;
113 unsigned char *name;
114{
115 int hashno;
116 struct hash_bucket *bp, *pbp = (struct hash_bucket *)0;
117
118 if (!table)
119 return;
120 if (!len)
121 len = strlen ((char *)name);
122
123 hashno = do_hash (name, len, table -> hash_count);
124
125 /* Go through the list looking for an entry that matches;
126 if we find it, delete it. */
127 for (bp = table -> buckets [hashno]; bp; bp = bp -> next) {
128 if ((!bp -> len &&
129 !strcmp ((char *)bp -> name, (char *)name)) ||
130 (bp -> len == len &&
131 !memcmp (bp -> name, name, len))) {
132 if (pbp) {
133 pbp -> next = bp -> next;
134 } else {
135 table -> buckets [hashno] = bp -> next;
136 }
137 free_hash_bucket (bp, "delete_hash_entry");
138 break;
139 }
140 pbp = bp; /* jwg, 9/6/96 - nice catch! */
141 }
142}
143
144unsigned char *hash_lookup (table, name, len)
145 struct hash_table *table;
146 unsigned char *name;
147 int len;
148{
149 int hashno;
150 struct hash_bucket *bp;
151
152 if (!table)
153 return (unsigned char *)0;
154
155 if (!len)
156 len = strlen ((char *)name);
157
158 hashno = do_hash (name, len, table -> hash_count);
159
160 for (bp = table -> buckets [hashno]; bp; bp = bp -> next) {
161 if (len == bp -> len && !memcmp (bp -> name, name, len))
162 return bp -> value;
163 }
164 return (unsigned char *)0;
165}
int strcmp(const char *String1, const char *String2)
Definition: utclib.c:469
int memcmp(void *Buffer1, void *Buffer2, ACPI_SIZE Count)
Definition: utclib.c:112
ACPI_SIZE strlen(const char *String)
Definition: utclib.c:269
void free_hash_bucket(struct hash_bucket *ptr, char *name)
Definition: alloc.c:89
struct hash_table * new_hash_table(int count)
Definition: alloc.c:57
struct hash_bucket * new_hash_bucket(void)
Definition: alloc.c:71
char copyright[]
Definition: main.c:27
void delete_hash_entry(struct hash_table *table, unsigned char *name, int len)
Definition: hash.c:110
unsigned char * hash_lookup(struct hash_table *table, unsigned char *name, int len)
Definition: hash.c:144
static __inline int do_hash(unsigned char *name, int len, int size)
Definition: hash.c:63
void add_hash(struct hash_table *table, unsigned char *name, int len, unsigned char *pointer)
Definition: hash.c:82
struct hash_table * new_hash()
Definition: hash.c:53
#define DEFAULT_HASH_SIZE
Definition: dhcpd.h:259
GLdouble s
Definition: gl.h:2039
GLsizeiptr size
Definition: glext.h:5919
GLsizei const GLvoid * pointer
Definition: glext.h:5848
GLenum GLsizei len
Definition: glext.h:6722
GLsizei GLenum const GLvoid GLsizei GLenum GLbyte GLbyte GLbyte GLdouble GLdouble GLdouble GLfloat GLfloat GLfloat GLint GLint GLint GLshort GLshort GLshort GLubyte GLubyte GLubyte GLuint GLuint GLuint GLushort GLushort GLushort GLbyte GLbyte GLbyte GLbyte GLdouble GLdouble GLdouble GLdouble GLfloat GLfloat GLfloat GLfloat GLint GLint GLint GLint GLshort GLshort GLshort GLshort GLubyte GLubyte GLubyte GLubyte GLuint GLuint GLuint GLuint GLushort GLushort GLushort GLushort GLboolean const GLdouble const GLfloat const GLint const GLshort const GLbyte const GLdouble const GLfloat const GLint const GLshort const GLdouble const GLfloat const GLint const GLshort const GLdouble const GLfloat const GLint const GLshort const GLdouble const GLfloat const GLint const GLshort const GLdouble const GLdouble const GLfloat const GLfloat const GLint const GLint const GLshort const GLshort const GLdouble const GLfloat const GLint const GLshort const GLdouble const GLfloat const GLint const GLshort const GLdouble const GLfloat const GLint const GLshort const GLdouble const GLfloat const GLint const GLshort const GLdouble const GLfloat const GLint const GLshort const GLdouble const GLfloat const GLint const GLshort const GLdouble const GLfloat const GLint const GLshort GLenum GLenum GLenum GLfloat GLenum GLint GLenum GLenum GLenum GLfloat GLenum GLenum GLint GLenum GLfloat GLenum GLint GLint GLushort GLenum GLenum GLfloat GLenum GLenum GLint GLfloat const GLubyte GLenum GLenum GLenum const GLfloat GLenum GLenum const GLint GLenum GLint GLint GLsizei GLsizei GLint GLenum GLenum const GLvoid GLenum GLenum const GLfloat GLenum GLenum const GLint GLenum GLenum const GLdouble GLenum GLenum const GLfloat GLenum GLenum const GLint GLsizei GLuint GLfloat GLuint GLbitfield GLfloat GLint GLuint GLboolean GLenum GLfloat GLenum GLbitfield GLenum GLfloat GLfloat GLint GLint const GLfloat GLenum GLfloat GLfloat GLint GLint GLfloat GLfloat GLint GLint const GLfloat GLint GLfloat GLfloat GLint GLfloat GLfloat GLint GLfloat GLfloat const GLdouble const GLfloat const GLdouble const GLfloat GLint i
Definition: glfuncs.h:248
static unsigned __int64 next
Definition: rand_nt.c:6
#define warn(...)
#define PROTO(x)
Definition: rosdhcp.h:57
#define memset(x, y, z)
Definition: compat.h:39
unsigned char * name
Definition: dhcpd.h:263
unsigned char * value
Definition: dhcpd.h:265
struct hash_bucket * buckets[DEFAULT_HASH_SIZE]
Definition: dhcpd.h:270
Definition: name.c:39
Definition: pdh_main.c:94