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

   1 /* -*-c-*-
   2  *
   3  * $Id: field.c,v 1.4 2004/04/08 01:36:15 mdw Exp $
   4  *
   5  * Abstract field operations
   6  *
   7  * (c) 2001 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 "field.h"
  33 #include "mp.h"
  34
  35 /*----- Main code ---------------------------------------------------------*/
  36
  37 /* --- @field_id@ --- *
  38  *
  39  * Arguments:   @field *f@ = pointer to a field
  40  *              @mp *d@ = a destination element
  41  *              @mp *x@ = a source element
  42  *
  43  * Returns:     The result element.
  44  *
  45  * Use:         An identity operation which can be used if your field has no
  46  *              internal representation.
  47  */
  48
  49 mp *field_id(field *f, mp *d, mp *x)
  50 {
  51   x = MP_COPY(x);
  52   if (d) MP_DROP(d);
  53   return (x);
  54 }
  55
  56 /* --- @field_samep@ --- *
  57  *
  58  * Arguments:   @field *f, *g@ = two fields
  59  *
  60  * Returns:     Nonzero if the fields are identical (not just isomorphic).
  61  *
  62  * Use:         Checks for sameness of fields.  This function does the full
  63  *              check, not just the field-type-specific check done by the
  64  *              @sampep@ field operation.
  65  */
  66
  67 int field_samep(field *f, field *g)
  68 {
  69   return (f->ops == g->ops && F_SAMEP(f, g));
  70 }
  71
  72 /* --- @field_stdsamep@ --- *
  73  *
  74  * Arguments:   @field *f, *g@ = two fields
  75  *
  76  * Returns:     Nonzero if the fields are identical (not just isomorphic).
  77  *
  78  * Use:         Standard sameness check, based on equality of the @m@
  79  *              member.
  80  */
  81
  82 int field_stdsamep(field *f, field *g)
  83 {
  84   return (MP_EQ(f->m, g->m));
  85 }
  86
  87 /*----- That's all, folks -------------------------------------------------*/