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

   1 /* -*-c-*-
   2  *
   3  * $Id$
   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 /*----- Header files ------------------------------------------------------*/
  31
  32 #define _GNU_SOURCE
  33 #include "config.h"
  34
  35 #include <stdio.h>
  36 #include <limits.h>
  37 #if __STDC_VERSION__ >= 199900l
  38 #  include <stdint.h>
  39 #  include <inttypes.h>
  40 #endif
  41
  42 /*----- Data types --------------------------------------------------------*/
  43
  44 /* --- Hack for GCC --- *
  45  *
  46  * WG14 in their infinite wisdom decided not to use the GCC constant name.
  47  */
  48
  49 #if __GNUC__ > 2 || (__GNUC__ == 2 && __GNUC_MINOR__ >= 91)
  50 #  define EXT __extension__
  51 #else
  52 #  define EXT
  53 #endif
  54
  55 #if defined(ULONG_LONG_MAX) && !defined(ULLONG_MAX)
  56 #  define ULLONG_MAX ULONG_LONG_MAX
  57 #endif
  58
  59 /* --- Choose the largest integer type --- */
  60
  61 #if defined(UINTMAX_MAX) && defined(PRIuMAX)
  62   typedef uintmax_t umax;
  63 # define P_UMAX PRIuMAX
  64 #elif defined(ULLONG_MAX)
  65   EXT typedef unsigned long long umax;
  66 # define P_UMAX "llu"
  67 #else
  68   typedef unsigned long umax;
  69 # define P_UMAX "lu"
  70 #endif
  71
  72 /* --- Table of interesting types --- *
  73  *
  74  * These are in preference order.
  75  */
  76
  77 enum {
  78   f_stdint = 1u,
  79   f_ext = 2u
  80 };
  81
  82 struct itype {
  83   const char *name;
  84   const char *suff;
  85   umax max;
  86   unsigned flags;
  87   unsigned bits;
  88 } tytab[] = {
  89   { "unsigned int",             "u",    UINT_MAX,               0 },
  90   { "unsigned short",           "u",    USHRT_MAX,              0 },
  91   { "unsigned long",            "ul",   ULONG_MAX,              0 },
  92 #ifdef ULLONG_MAX
  93   { "unsigned long long",       "ull",  EXT ULLONG_MAX,         f_ext },
  94 #endif
  95 #ifdef UINTMAX_MAX
  96   { "uintmax_t",                "u",    UINTMAX_MAX,            f_stdint },
  97 #endif
  98   { 0,                          0 },
  99 };
 100
 101 typedef struct itype itype;
 102
 103 /*----- Main code ---------------------------------------------------------*/
 104
 105 int main(int argc, char *argv[])
 106 {
 107   itype *i;
 108   itype *largest, *mpw, *mpd;
 109   const static char *extstr = "CATACOMB_MPTYPES_EXTENSION ";
 110   unsigned p2;
 111
 112   /* --- Find the bitcounts --- */
 113
 114   for (i = tytab; i->name; i++) {
 115     unsigned bits;
 116     umax u = i->max;
 117     for (bits = 0; u; bits++)
 118       u >>= 1;
 119     i->bits = bits;
 120   }
 121
 122   /* --- Now try to find the interesting types --- *
 123    *
 124    * The first thing to do is to find the largest type.  Then I find the
 125    * `best' type which is less than half that size, and then the `best' type
 126    * which is twice as big as that one.
 127    */
 128
 129 #if defined(FORCE_MPW_CUSSID)
 130   largest = mpd = &tytab[3];
 131   mpw = &tytab[2];
 132   mpw->bits = 19; mpw->max = 0x7ffff;
 133   mpd->bits = 38; mpd->max = 0x3fffffffffll;
 134 #elif defined(FORCE_MPW_SHORT)
 135   largest = mpd = &tytab[2];
 136   mpw = &tytab[1];
 137   mpw->bits = 16; mpw->max = 0xffff;
 138   mpd->bits = 32; mpd->max = 0xffffffff;
 139 #else
 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 #endif
 163   for (p2 = 1; (p2 << 1) < mpw->bits; p2 <<= 1);
 164
 165   /* --- Output time --- */
 166
 167   puts("\
 168 /* -*-c-*-\n\
 169  *\n\
 170  * mptypes.h [generated]\n\
 171  */\n\
 172 \n\
 173 #ifndef CATACOMB_MPTYPES_H\n\
 174 #define CATACOMB_MPTYPES_H\n\
 175 ");
 176   if ((mpd->flags | mpw->flags) & f_stdint) {
 177     puts("\
 178 #if __STDC_VERSION__ >= 199900l\n\
 179 #  include <stdint.h>\n\
 180 #endif\n\
 181 ");
 182   }
 183   if ((mpd->flags | mpw->flags) & f_ext) {
 184     printf("\
 185 #if __GNUC__ > 2 || (__GNUC__ == 2 && __GNUC_MINOR__ >= 91)\n\
 186 #  define %s __extension__\n\
 187 #else\n\
 188 #  define %s\n\
 189 #endif\n\
 190 ", extstr, extstr);
 191   }
 192   printf("\
 193 %stypedef %s mpw;\n\
 194 #define MPW_BITS %u\n\
 195 #define MPW_P2 %u\n\
 196 #define MPW_MAX %s%" P_UMAX "%s\n\
 197 \n\
 198 %stypedef %s mpd;\n\
 199 #define MPD_BITS %u\n\
 200 #define MPD_MAX %s%" P_UMAX "%s\n\
 201 \n\
 202 #endif\n\
 203 ",
 204   mpw->flags & f_ext ? extstr : "", mpw->name,
 205   mpw->bits, p2,
 206   mpw->flags & f_ext ? extstr : "", mpw->max, mpw->suff,
 207   mpd->flags & f_ext ? extstr : "", mpd->name,
 208   mpd->bits,
 209   mpd->flags & f_ext ? extstr : "", mpd->max, mpd->suff);
 210
 211   return (0);
 212 }
 213
 214 /*----- That's all, folks -------------------------------------------------*/