mdoc_hash.c

   1 /*      $Id: mdoc_hash.c,v 1.10 2009/09/16 20:49:06 kristaps Exp $ */
   2 /*
   3  * Copyright (c) 2008, 2009 Kristaps Dzonsons <kristaps@kth.se>
   4  *
   5  * Permission to use, copy, modify, and distribute this software for any
   6  * purpose with or without fee is hereby granted, provided that the above
   7  * copyright notice and this permission notice appear in all copies.
   8  *
   9  * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
  10  * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
  11  * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
  12  * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
  13  * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
  14  * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
  15  * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
  16  */
  17 #include <sys/types.h>
  18
  19 #include <assert.h>
  20 #include <ctype.h>
  21 #include <limits.h>
  22 #include <stdlib.h>
  23 #include <stdio.h>
  24 #include <string.h>
  25
  26 #include "libmdoc.h"
  27
  28 static  u_char           table[27 * 12];
  29
  30
  31 void
  32 mdoc_hash_init(void)
  33 {
  34         int              i, j, major;
  35         const char      *p;
  36
  37         memset(table, UCHAR_MAX, sizeof(table));
  38
  39         for (i = 0; i < MDOC_MAX; i++) {
  40                 p = mdoc_macronames[i];
  41
  42                 if (isalpha((u_char)p[1]))
  43                         major = 12 * (tolower((u_char)p[1]) - 97);
  44                 else
  45                         major = 12 * 26;
  46
  47                 for (j = 0; j < 12; j++)
  48                         if (UCHAR_MAX == table[major + j]) {
  49                                 table[major + j] = (u_char)i;
  50                                 break;
  51                         }
  52
  53                 assert(j < 12);
  54         }
  55 }
  56
  57
  58 int
  59 mdoc_hash_find(const char *p)
  60 {
  61         int               major, i, j;
  62
  63         if (0 == p[0])
  64                 return(MDOC_MAX);
  65         if ( ! isalpha((u_char)p[0]) && '%' != p[0])
  66                 return(MDOC_MAX);
  67
  68         if (isalpha((u_char)p[1]))
  69                 major = 12 * (tolower((u_char)p[1]) - 97);
  70         else if ('1' == p[1])
  71                 major = 12 * 26;
  72         else
  73                 return(MDOC_MAX);
  74
  75         if (p[2] && p[3])
  76                 return(MDOC_MAX);
  77
  78         for (j = 0; j < 12; j++) {
  79                 if (UCHAR_MAX == (i = table[major + j]))
  80                         break;
  81                 if (0 == strcmp(p, mdoc_macronames[i]))
  82                         return(i);
  83         }
  84
  85         return(MDOC_MAX);
  86 }
  87