lib/asn1/hash.h

   1 /*
   2  * Copyright (c) 1997 Kungliga Tekniska Högskolan
   3  * (Royal Institute of Technology, Stockholm, Sweden).
   4  * All rights reserved.
   5  *
   6  * Redistribution and use in source and binary forms, with or without
   7  * modification, are permitted provided that the following conditions
   8  * are met:
   9  *
  10  * 1. Redistributions of source code must retain the above copyright
  11  *    notice, this list of conditions and the following disclaimer.
  12  *
  13  * 2. Redistributions in binary form must reproduce the above copyright
  14  *    notice, this list of conditions and the following disclaimer in the
  15  *    documentation and/or other materials provided with the distribution.
  16  *
  17  * 3. All advertising materials mentioning features or use of this software
  18  *    must display the following acknowledgement:
  19  *      This product includes software developed by Kungliga Tekniska
  20  *      Högskolan and its contributors.
  21  *
  22  * 4. Neither the name of the Institute nor the names of its contributors
  23  *    may be used to endorse or promote products derived from this software
  24  *    without specific prior written permission.
  25  *
  26  * THIS SOFTWARE IS PROVIDED BY THE INSTITUTE AND CONTRIBUTORS ``AS IS'' AND
  27  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  28  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  29  * ARE DISCLAIMED.  IN NO EVENT SHALL THE INSTITUTE OR CONTRIBUTORS BE LIABLE
  30  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  31  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  32  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  33  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  34  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  35  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  36  * SUCH DAMAGE.
  37  */
  38
  39 /*
  40  * hash.h. Header file for hash table functions
  41  */
  42
  43 /* $Id$ */
  44
  45 struct hashentry {              /* Entry in bucket */
  46      struct hashentry **prev;
  47      struct hashentry *next;
  48      void *ptr;
  49 };
  50
  51 typedef struct hashentry Hashentry;
  52
  53 struct hashtab {                /* Hash table */
  54      int (*cmp)(void *, void *); /* Compare function */
  55      unsigned (*hash)(void *);  /* hash function */
  56      int sz;                    /* Size */
  57      Hashentry *tab[1];         /* The table */
  58 };
  59
  60 typedef struct hashtab Hashtab;
  61
  62 /* prototypes */
  63
  64 Hashtab *hashtabnew(int sz,
  65                     int (*cmp)(void *, void *),
  66                     unsigned (*hash)(void *));  /* Make new hash table */
  67
  68 void *hashtabsearch(Hashtab *htab, /* The hash table */
  69                     void *ptr); /*  The key */
  70
  71
  72 void *hashtabadd(Hashtab *htab, /* The hash table */
  73                void *ptr);      /* The element */
  74
  75 int _hashtabdel(Hashtab *htab,  /* The table */
  76                 void *ptr,      /* Key */
  77                 int freep);     /* Free data part? */
  78
  79 void hashtabforeach(Hashtab *htab,
  80                     int (*func)(void *ptr, void *arg),
  81                     void *arg);
  82
  83 unsigned hashadd(const char *s);                /* Standard hash function */
  84 unsigned hashcaseadd(const char *s);            /* Standard hash function */
  85 unsigned hashjpw(const char *s);                /* another hash function */
  86
  87 /* macros */
  88
  89  /* Don't free space */
  90 #define hashtabdel(htab,key)  _hashtabdel(htab,key,FALSE)
  91
  92 #define hashtabfree(htab,key) _hashtabdel(htab,key,TRUE) /* Do! */