git.distorted.org.uk Git - u/mdw/catacomb/blob - qdparse.c

   1 /* -*-c-*-
   2  *
   3  * $Id: qdparse.c,v 1.1 2004/03/27 17:54:12 mdw Exp $
   4  *
   5  * Quick-and-dirty parser
   6  *
   7  * (c) 2004 Straylight/Edgeware
   8  */
   9
  10 /*----- Licensing notice --------------------------------------------------*
  11  *
  12  * This file is part of Catacomb.
  13  *
  14  * Catacomb is free software; you can redistribute it and/or modify
  15  * it under the terms of the GNU Library General Public License as
  16  * published by the Free Software Foundation; either version 2 of the
  17  * License, or (at your option) any later version.
  18  *
  19  * Catacomb is distributed in the hope that it will be useful,
  20  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  21  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  22  * GNU Library General Public License for more details.
  23  *
  24  * You should have received a copy of the GNU Library General Public
  25  * License along with Catacomb; if not, write to the Free
  26  * Software Foundation, Inc., 59 Temple Place - Suite 330, Boston,
  27  * MA 02111-1307, USA.
  28  */
  29
  30 /*----- Revision history --------------------------------------------------*
  31  *
  32  * $Log: qdparse.c,v $
  33  * Revision 1.1  2004/03/27 17:54:12  mdw
  34  * Standard curves and curve checking.
  35  *
  36  */
  37
  38 /*----- Header files ------------------------------------------------------*/
  39
  40 #include <ctype.h>
  41 #include <string.h>
  42
  43 #include "qdparse.h"
  44
  45 /*----- Main code ---------------------------------------------------------*/
  46
  47 /* --- @qd_skipspc@ --- *
  48  *
  49  * Arguments:   @qd_parse *qd@ = context
  50  *
  51  * Returns:     ---
  52  *
  53  * Use:         Skips spaces in the string.  No errors.
  54  */
  55
  56 void qd_skipspc(qd_parse *qd)
  57 {
  58   while (isspace((unsigned char)*qd->p))
  59     qd->p++;
  60 }
  61
  62 /* --- @qd_delim@ --- *
  63  *
  64  * Arguments:   @qd_parse *qd@ = context
  65  *              @int ch@ = character to compare with
  66  *
  67  * Returns:     Nonzero if it was, zero if it wasn't.
  68  *
  69  * Use:         Checks the next (non-whitespace) character is what we
  70  *              expect.  If it is, the character is eaten; otherwise it's no
  71  *              big deal.
  72  */
  73
  74 int qd_delim(qd_parse *qd, int ch)
  75 {
  76   qd_skipspc(qd);
  77   if (*qd->p != ch)
  78     return (0);
  79   qd->p++;
  80   return (1);
  81 }
  82
  83 /* --- @qd_enum@ --- *
  84  *
  85  * Arguments:   @qd_parse *qd@ = context
  86  *              @const char *e@ = list of enum strings, space separated
  87  *
  88  * Returns:     Index of the string matched, or @-1@.
  89  *
  90  * Use:         Matches a keyword.
  91  */
  92
  93 int qd_enum(qd_parse *qd, const char *e)
  94 {
  95   size_t n;
  96   int i = 0;
  97
  98   qd_skipspc(qd);
  99   for (;;) {
 100     e += strspn(e, ", ");
 101     if (!*e) break;
 102     n = strcspn(e, ", ");
 103     if (strncmp(qd->p, e, n) == 0 && !isalnum((unsigned char)qd->p[n])) {
 104       qd->p += n;
 105       return (i);
 106     }
 107     i++; e += n;
 108   }
 109   qd->e = "unrecognized keyword";
 110   return (-1);
 111 }
 112
 113 /* --- @qd_getmp@ --- *
 114  *
 115  * Arguments:   @qd_parse *qd@ = context
 116  *
 117  * Returns:     The integer extracted, or null.
 118  *
 119  * Use:         Parses a multiprecision integer from a string.
 120  */
 121
 122 mp *qd_getmp(qd_parse *qd)
 123 {
 124   char *q;
 125   mp *m;
 126
 127   qd_skipspc(qd);
 128   m = mp_readstring(MP_NEW, qd->p, &q, 0);
 129   if (m && !isalnum((unsigned char)*q))
 130     qd->p = q;
 131   else {
 132     mp_drop(m);
 133     qd->e = "bad number";
 134   }
 135   return (m);
 136 }
 137
 138 /* --- @qd_eofp@ --- *
 139  *
 140  * Arguments:   @qd_parse *qd@ = context
 141  *
 142  * Returns:     Nonzero if at EOF, zero otherwise.
 143  */
 144
 145 int qd_eofp(qd_parse *qd)
 146 {
 147   qd_skipspc(qd);
 148   return (!*qd->p);
 149 }
 150
 151 /*----- That's all, folks -------------------------------------------------*/