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

   1 /* -*-c-*-
   2  *
   3  * $Id: mptypes.c,v 1.4 2000/10/08 12:05:24 mdw Exp $
   4  *
   5  * Generate `mptypes.h' header file for current architecture
   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: mptypes.c,v $
  33  * Revision 1.4  2000/10/08 12:05:24  mdw
  34  * Make later versions of GCC shut up about @long long@.
  35  *
  36  * Revision 1.3  1999/12/10 23:29:48  mdw
  37  * Change header file guard names.
  38  *
  39  * Revision 1.2  1999/11/13 01:54:32  mdw
  40  * Format source code properly ;-).  Attach suffixes to the `max'
  41  * constants.
  42  *
  43  */
  44
  45 /*----- Header files ------------------------------------------------------*/
  46
  47 #define _GNU_SOURCE
  48 #include <stdio.h>
  49 #include <limits.h>
  50 #if __STDC_VERSION__ >= 199900l
  51 #  include <stdint.h>
  52 #endif
  53
  54 /*----- Data types --------------------------------------------------------*/
  55
  56 /* --- Hack for GCC --- *
  57  *
  58  * WG14 in their infinite wisdom decided not to use the GCC constant name.
  59  */
  60
  61 #if __GNUC__ > 2 || (__GNUC__ == 2 && __GNUC_MINOR__ >= 91)
  62 #  define EXT __extension__
  63 #else
  64 #  define EXT
  65 #endif
  66
  67 #if defined(ULONG_LONG_MAX) && !defined(ULLONG_MAX)
  68 #  define ULLONG_MAX ULONG_LONG_MAX
  69 #endif
  70
  71 /* --- Choose the largest integer type --- */
  72
  73 #if defined(UINTMAX_MAX)
  74   typedef uintmax_t umax;
  75 # define P_UMAX PRIuMAX
  76 #elif defined(ULLONG_MAX)
  77   __extension__ typedef unsigned long long umax;
  78 # define P_UMAX "%llu"
  79 #else
  80   typedef unsigned long umax;
  81 # define P_UMAX "%lu"
  82 #endif
  83
  84 /* --- Table of interesting types --- *
  85  *
  86  * These are in preference order.
  87  */
  88
  89 enum {
  90   f_stdint = 1u,
  91   f_ext = 2u
  92 };
  93
  94 struct itype {
  95   const char *name;
  96   const char *suff;
  97   umax max;
  98   unsigned flags;
  99   unsigned bits;
 100 } tytab[] = {
 101   { "unsigned int",             "u",    UINT_MAX,               0 },
 102   { "unsigned short",           "u",    USHRT_MAX,              0 },
 103   { "unsigned long",            "ul",   ULONG_MAX,              0 },
 104 #ifdef ULLONG_MAX
 105   { "unsigned long long",       "ull",  EXT ULLONG_MAX,         f_ext },
 106 #endif
 107 #ifdef UINTMAX_MAX
 108   { "uintmax_t",                "u",    UINTMAX_MAX,            f_stdint },
 109 #endif
 110   { 0,                          0 },
 111 };
 112
 113 typedef struct itype itype;
 114
 115 /*----- Main code ---------------------------------------------------------*/
 116
 117 int main(int argc, char *argv[])
 118 {
 119   itype *i;
 120   itype *largest, *mpw, *mpd;
 121   const static char *extstr = "CATACOMB_MPTYPES_EXTENSION ";
 122
 123   /* --- Find the bitcounts --- */
 124
 125   for (i = tytab; i->name; i++) {
 126     unsigned bits;
 127     umax u = i->max;
 128     for (bits = 0; u; bits++)
 129       u >>= 1;
 130     i->bits = bits;
 131   }
 132
 133   /* --- Now try to find the interesting types --- *
 134    *
 135    * The first thing to do is to find the largest type.  Then I find the
 136    * `best' type which is less than half that size, and then the `best' type
 137    * which is twice as big as that one.
 138    */
 139
 140   largest = tytab;
 141   for (i = tytab; i->name; i++) {
 142     if (i->bits > largest->bits)
 143       largest = i;
 144   }
 145   for (mpw = 0, i = tytab; i->name; i++) {
 146     if (i->bits * 2 <= largest->bits && (!mpw || i->bits > mpw->bits))
 147       mpw = i;
 148   }
 149   if (!mpw)
 150     mpw = tytab;
 151   for (mpd = 0, i = tytab; i->name; i++) {
 152     if (i->bits >= mpw->bits * 2 && (!mpd || i->bits < mpd->bits))
 153       mpd = i;
 154   }
 155   if (!mpd) {
 156     static itype w, d;
 157     d = w = *mpw;
 158     w.bits /= 2; w.max = ~(~((umax)0) << w.bits);
 159     d.bits = w.bits * 2; d.max = ~(~((umax)0) << d.bits);
 160     mpw = &w; mpd = &d;
 161   }
 162
 163   /* --- Output time --- */
 164
 165   puts("\
 166 /* -*-c-*-\n\
 167  *\n\
 168  * mptypes.h [generated]\n\
 169  */\n\
 170 \n\
 171 #ifndef CATACOMB_MPTYPES_H\n\
 172 #define CATACOMB_MPTYPES_H\n\
 173 ");
 174   if ((mpd->flags | mpw->flags) & f_stdint) {
 175     puts("\
 176 #if __STDC_VERSION__ >= 199900l\n\
 177 #  include <stdint.h>\n\
 178 #endif\n\
 179 ");
 180   }
 181   if ((mpd->flags | mpw->flags) & f_ext) {
 182     printf("\
 183 #if __GNUC__ > 2 || (__GNUC__ == 2 && __GNUC_MINOR__ >= 91)\n\
 184 #  define %s __extension__\n\
 185 #else\n\
 186 #  define %s\n\
 187 #endif\n\
 188 ", extstr, extstr);
 189   }
 190   printf("\
 191 %stypedef %s mpw;\n\
 192 #define MPW_BITS %u\n\
 193 #define MPW_MAX %s" P_UMAX "%s\n\
 194 \n\
 195 %stypedef %s mpd;\n\
 196 #define MPD_BITS %u\n\
 197 #define MPD_MAX %s" P_UMAX "%s\n\
 198 \n\
 199 #endif\n\
 200 ",
 201   mpw->flags & f_ext ? extstr : "", mpw->name,
 202   mpw->bits,
 203   mpw->flags & f_ext ? extstr : "", mpw->max, mpw->suff,
 204   mpd->flags & f_ext ? extstr : "", mpd->name,
 205   mpd->bits,
 206   mpd->flags & f_ext ? extstr : "", mpd->max, mpd->suff);
 207
 208   return (0);
 209 }
 210
 211 /*----- That's all, folks -------------------------------------------------*/