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

   1 /* -*-c-*-
   2  *
   3  * $Id: mpscan.c,v 1.1 1999/09/03 08:41:12 mdw Exp $
   4  *
   5  * Sequential bit scan of multiprecision integers
   6  *
   7  * (c) 1999 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: mpscan.c,v $
  33  * Revision 1.1  1999/09/03 08:41:12  mdw
  34  * Initial import.
  35  *
  36  */
  37
  38 /*----- Header files ------------------------------------------------------*/
  39
  40 /*----- Data structures ---------------------------------------------------*/
  41
  42 /*----- Static variables --------------------------------------------------*/
  43
  44 /*----- Main code ---------------------------------------------------------*/
  45
  46 /* --- @mpscan_initx@ --- *
  47  *
  48  * Arguments:   @mpscan *m@ = pointer to bitscanner structure
  49  *              @const mpw *v@ = vector of words to scan
  50  *              @size_t len@ = length of vector in words
  51  *
  52  * Returns:     ---
  53  *
  54  * Use:         Initializes a bitscanner from a low-level vector-and-length
  55  *              representation of an integer.  Initially no bit is ready; you
  56  *              must call @mpscan_step@ before anything useful will come
  57  *              out.
  58  */
  59
  60 void mpscan_initx(mpscan *m, const mpw *v, size_t len)
  61 {
  62   MPSCAN_INITX(m, v, len);
  63 }
  64
  65 /* --- @mpscan_step@ --- *
  66  *
  67  * Arguments:   @mpscan *m@ = pointer to bitscanner
  68  *
  69  * Returns:     Nonzero if there is another bit to read.
  70  *
  71  * Use:         Steps on to the next bit in the integer.  The macro version
  72  *              evaluates its argument multiple times.
  73  */
  74
  75 int mpscan_step(mpscan *m) { return (MPSCAN_STEP(m)); }
  76
  77 /* --- @mpscan_bit@ --- *
  78  *
  79  * Arguments:   @const mpscan *m@ = pointer to bitscanner
  80  *
  81  * Returns:     The value of the current bit.
  82  *
  83  * Use:         Reads the value of the current bit looked at by a
  84  *              bitscanner.
  85  */
  86
  87 int mpscan_bit(const mpscan *m) { return (MPSCAN_BIT(m)); }
  88
  89 /*----- That's all, folks -------------------------------------------------*/