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

   1 /* -*-c-*-
   2  *
   3  * $Id: group-string.c,v 1.2 2004/04/08 01:36:15 mdw Exp $
   4  *
   5  * String I/O for group elements
   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 /*----- Header files ------------------------------------------------------*/
  31
  32 #include "group.h"
  33
  34 /*----- Main code ---------------------------------------------------------*/
  35
  36 /* --- @group_readstring@ --- *
  37  *
  38  * Arguments:   @group *g@ = an abstract group
  39  *              @ge *d@ = destination group element
  40  *              @const char *p@ = where the string is
  41  *              @char **end@ = where to put the end pointer
  42  *
  43  * Returns:     Zero on success, nonzero on failure.
  44  *
  45  * Use:         Parses a group element from a string.
  46  */
  47
  48 int group_readstring(group *g, ge *d, const char *p, char **end)
  49 {
  50   mptext_stringctx ms;
  51
  52   ms.buf = (/*unconst*/ char *)p;
  53   ms.lim = (/*unconst*/ char *)p + strlen(p);
  54   if (G_READ(g, d, &mptext_stringops, &ms))
  55     return (-1);
  56   if (end) *end = ms.buf;
  57   return (0);
  58 }
  59
  60 /* --- @group_writestring@ --- *
  61  *
  62  * Arguments:   @group *g@ = an abstract group
  63  *              @ge *x@ = a group element
  64  *              @char *p@ = where the string should go
  65  *              @size_t sz@ = how long the buffer is
  66  *
  67  * Returns:     Zero on success, nonzero on failure.
  68  *
  69  * Use:         Writes a group element to a string buffer.
  70  */
  71
  72 int group_writestring(group *g, ge *x, char *p, size_t sz)
  73 {
  74   mptext_stringctx ms;
  75
  76   ms.buf = p;
  77   ms.lim = p + sz - 1;
  78   if (G_WRITE(g, x, &mptext_stringops, &ms))
  79     return (-1);
  80   *ms.buf = 0;
  81   return (0);
  82 }
  83
  84 /*----- That's all, folks -------------------------------------------------*/