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. Neither the name of the Institute nor the names of its contributors
  18  *    may be used to endorse or promote products derived from this software
  19  *    without specific prior written permission.
  20  *
  21  * THIS SOFTWARE IS PROVIDED BY THE INSTITUTE AND CONTRIBUTORS ``AS IS'' AND
  22  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  23  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  24  * ARE DISCLAIMED.  IN NO EVENT SHALL THE INSTITUTE OR CONTRIBUTORS BE LIABLE
  25  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  26  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  27  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  28  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  29  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  30  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  31  * SUCH DAMAGE.
  32  */
  33
  34 /*
  35  * hash.h. Header file for hash table functions
  36  */
  37
  38 /* $Id$ */
  39
  40 struct hashentry {              /* Entry in bucket */
  41      struct hashentry **prev;
  42      struct hashentry *next;
  43      void *ptr;
  44 };
  45
  46 typedef struct hashentry Hashentry;
  47
  48 struct hashtab {                /* Hash table */
  49      int (*cmp)(void *, void *); /* Compare function */
  50      unsigned (*hash)(void *);  /* hash function */
  51      int sz;                    /* Size */
  52      Hashentry *tab[1];         /* The table */
  53 };
  54
  55 typedef struct hashtab Hashtab;
  56
  57 /* prototypes */
  58
  59 Hashtab *hashtabnew(int sz,
  60                     int (*cmp)(void *, void *),
  61                     unsigned (*hash)(void *));  /* Make new hash table */
  62
  63 void *hashtabsearch(Hashtab *htab, /* The hash table */
  64                     void *ptr); /*  The key */
  65
  66
  67 void *hashtabadd(Hashtab *htab, /* The hash table */
  68                void *ptr);      /* The element */
  69
  70 int _hashtabdel(Hashtab *htab,  /* The table */
  71                 void *ptr,      /* Key */
  72                 int freep);     /* Free data part? */
  73
  74 void hashtabforeach(Hashtab *htab,
  75                     int (*func)(void *ptr, void *arg),
  76                     void *arg);
  77
  78 unsigned hashadd(const char *s);                /* Standard hash function */
  79 unsigned hashcaseadd(const char *s);            /* Standard hash function */
  80 unsigned hashjpw(const char *s);                /* another hash function */
  81
  82 /* macros */
  83
  84  /* Don't free space */
  85 #define hashtabdel(htab,key)  _hashtabdel(htab,key,FALSE)
  86
  87 #define hashtabfree(htab,key) _hashtabdel(htab,key,TRUE) /* Do! */