mdoc_hash.c

   1 /*      $Id: mdoc_hash.c,v 1.15 2010/05/17 22:11:42 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 #ifdef HAVE_CONFIG_H
  18 #include "config.h"
  19 #endif
  20
  21 #include <sys/types.h>
  22
  23 #include <assert.h>
  24 #include <ctype.h>
  25 #include <limits.h>
  26 #include <stdlib.h>
  27 #include <stdio.h>
  28 #include <string.h>
  29
  30 #include "mandoc.h"
  31 #include "libmdoc.h"
  32
  33 static  u_char           table[27 * 12];
  34
  35 /*
  36  * XXX - this hash has global scope, so if intended for use as a library
  37  * with multiple callers, it will need re-invocation protection.
  38  */
  39 void
  40 mdoc_hash_init(void)
  41 {
  42         int              i, j, major;
  43         const char      *p;
  44
  45         memset(table, UCHAR_MAX, sizeof(table));
  46
  47         for (i = 0; i < (int)MDOC_MAX; i++) {
  48                 p = mdoc_macronames[i];
  49
  50                 if (isalpha((u_char)p[1]))
  51                         major = 12 * (tolower((u_char)p[1]) - 97);
  52                 else
  53                         major = 12 * 26;
  54
  55                 for (j = 0; j < 12; j++)
  56                         if (UCHAR_MAX == table[major + j]) {
  57                                 table[major + j] = (u_char)i;
  58                                 break;
  59                         }
  60
  61                 assert(j < 12);
  62         }
  63 }
  64
  65 enum mdoct
  66 mdoc_hash_find(const char *p)
  67 {
  68         int               major, i, j;
  69
  70         if (0 == p[0])
  71                 return(MDOC_MAX);
  72         if ( ! isalpha((u_char)p[0]) && '%' != p[0])
  73                 return(MDOC_MAX);
  74
  75         if (isalpha((u_char)p[1]))
  76                 major = 12 * (tolower((u_char)p[1]) - 97);
  77         else if ('1' == p[1])
  78                 major = 12 * 26;
  79         else
  80                 return(MDOC_MAX);
  81
  82         if (p[2] && p[3])
  83                 return(MDOC_MAX);
  84
  85         for (j = 0; j < 12; j++) {
  86                 if (UCHAR_MAX == (i = table[major + j]))
  87                         break;
  88                 if (0 == strcmp(p, mdoc_macronames[i]))
  89                         return((enum mdoct)i);
  90         }
  91
  92         return(MDOC_MAX);
  93 }