nsprpub/pr/include/gencfg.c

   1 /* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
   2 /* This Source Code Form is subject to the terms of the Mozilla Public
   3  * License, v. 2.0. If a copy of the MPL was not distributed with this
   4  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
   5
   6 #include <stdio.h>
   7
   8 #if defined(__sun)
   9 #  ifndef SOLARIS
  10 error -
  11     SOLARIS is not defined
  12 #  endif
  13 #endif
  14
  15 #if defined(__hpux)
  16 #  ifndef HPUX
  17         error -
  18     HPUX is not defined
  19 #  endif
  20 #endif
  21
  22 #if defined(__alpha)
  23 #  if !(defined(_WIN32)) && !(defined(__linux)) && !(defined(__FreeBSD__))
  24         error -
  25     None of _WIN32,
  26     __linux, or __FreeBSD__ is defined
  27 #  endif
  28 #endif
  29
  30 #if defined(_IBMR2)
  31 #  ifndef AIX
  32                          error -
  33                      AIX is not defined
  34 #  endif
  35 #endif
  36
  37 #if defined(linux)
  38 #  ifndef LINUX
  39                          error -
  40                      LINUX is not defined
  41 #  endif
  42 #endif
  43
  44 #if defined(__APPLE__)
  45 #  ifndef DARWIN
  46                          error -
  47                      DARWIN is not defined
  48 #  endif
  49 #endif
  50
  51 /************************************************************************/
  52
  53 /* Generate cpucfg.h */
  54
  55 #ifdef XP_PC
  56 #  ifdef WIN32
  57 #    define INT64 _PRInt64
  58 #  else
  59 #    define INT64 long
  60 #  endif
  61 #else
  62 #  if defined(HPUX)
  63 #    define INT64 long
  64 #  else
  65 #    define INT64 long long
  66 #  endif
  67 #endif
  68
  69                      struct align_short {
  70   char c;
  71   short a;
  72 };
  73 struct align_int {
  74   char c;
  75   int a;
  76 };
  77 struct align_long {
  78   char c;
  79   long a;
  80 };
  81 struct align_PRInt64 {
  82   char c;
  83   INT64 a;
  84 };
  85 struct align_fakelonglong {
  86   char c;
  87   struct {
  88     long hi, lo;
  89   } a;
  90 };
  91 struct align_float {
  92   char c;
  93   float a;
  94 };
  95 struct align_double {
  96   char c;
  97   double a;
  98 };
  99 struct align_pointer {
 100   char c;
 101   void* a;
 102 };
 103
 104 #define ALIGN_OF(type) (((char*)&(((struct align_##type*)0)->a)) - ((char*)0))
 105
 106 int bpb;
 107
 108 /* Used if shell doesn't support redirection. By default, assume it does. */
 109 FILE* stream;
 110
 111 static int Log2(int n) {
 112   int log2 = 0;
 113
 114   if (n & (n - 1)) {
 115     log2++;
 116   }
 117   if (n >> 16) {
 118     log2 += 16, n >>= 16;
 119   }
 120   if (n >> 8) {
 121     log2 += 8, n >>= 8;
 122   }
 123   if (n >> 4) {
 124     log2 += 4, n >>= 4;
 125   }
 126   if (n >> 2) {
 127     log2 += 2, n >>= 2;
 128   }
 129   if (n >> 1) {
 130     log2++;
 131   }
 132   return log2;
 133 }
 134
 135 /* We assume that int's are 32 bits */
 136 static void do64(void) {
 137   union {
 138     int i;
 139     char c[4];
 140   } u;
 141
 142   u.i = 0x01020304;
 143   if (u.c[0] == 0x01) {
 144     fprintf(stream, "#undef  IS_LITTLE_ENDIAN\n");
 145     fprintf(stream, "#define IS_BIG_ENDIAN 1\n\n");
 146   } else {
 147     fprintf(stream, "#define IS_LITTLE_ENDIAN 1\n");
 148     fprintf(stream, "#undef  IS_BIG_ENDIAN\n\n");
 149   }
 150 }
 151
 152 static void do32(void) {
 153   union {
 154     long i;
 155     char c[4];
 156   } u;
 157
 158   u.i = 0x01020304;
 159   if (u.c[0] == 0x01) {
 160     fprintf(stream, "#undef  IS_LITTLE_ENDIAN\n");
 161     fprintf(stream, "#define IS_BIG_ENDIAN 1\n\n");
 162   } else {
 163     fprintf(stream, "#define IS_LITTLE_ENDIAN 1\n");
 164     fprintf(stream, "#undef  IS_BIG_ENDIAN\n\n");
 165   }
 166 }
 167
 168 /*
 169 ** Concievably this could actually be used; but there is lots of code out
 170 ** there with and's and shift's in it that assumes a byte is 8 bits, so
 171 ** forget about porting THIS code to those non 8 bit byte machines.
 172 */
 173 static void BitsPerByte(void) { bpb = 8; }
 174
 175 int main(int argc, char** argv) {
 176   BitsPerByte();
 177
 178   /* If we got a command line argument, try to use it as the stream. */
 179   ++argv;
 180   if (*argv) {
 181     if (!(stream = fopen(*argv, "wt"))) {
 182       fprintf(stderr, "Could not write to output file %s.\n", *argv);
 183       return 1;
 184     }
 185   } else {
 186     stream = stdout;
 187   }
 188
 189   fprintf(stream, "#ifndef nspr_cpucfg___\n");
 190   fprintf(stream, "#define nspr_cpucfg___\n\n");
 191
 192   fprintf(stream, "/* AUTOMATICALLY GENERATED - DO NOT EDIT */\n\n");
 193
 194   if (sizeof(long) == 8) {
 195     do64();
 196   } else {
 197     do32();
 198   }
 199   fprintf(stream, "#define PR_BYTES_PER_BYTE   %d\n", sizeof(char));
 200   fprintf(stream, "#define PR_BYTES_PER_SHORT  %d\n", sizeof(short));
 201   fprintf(stream, "#define PR_BYTES_PER_INT    %d\n", sizeof(int));
 202   fprintf(stream, "#define PR_BYTES_PER_INT64  %d\n", 8);
 203   fprintf(stream, "#define PR_BYTES_PER_LONG   %d\n", sizeof(long));
 204   fprintf(stream, "#define PR_BYTES_PER_FLOAT  %d\n", sizeof(float));
 205   fprintf(stream, "#define PR_BYTES_PER_DOUBLE %d\n\n", sizeof(double));
 206
 207   fprintf(stream, "#define PR_BITS_PER_BYTE    %d\n", bpb);
 208   fprintf(stream, "#define PR_BITS_PER_SHORT   %d\n", bpb * sizeof(short));
 209   fprintf(stream, "#define PR_BITS_PER_INT     %d\n", bpb * sizeof(int));
 210   fprintf(stream, "#define PR_BITS_PER_INT64   %d\n", bpb * 8);
 211   fprintf(stream, "#define PR_BITS_PER_LONG    %d\n", bpb * sizeof(long));
 212   fprintf(stream, "#define PR_BITS_PER_FLOAT   %d\n", bpb * sizeof(float));
 213   fprintf(stream, "#define PR_BITS_PER_DOUBLE  %d\n\n", bpb * sizeof(double));
 214
 215   fprintf(stream, "#define PR_BITS_PER_BYTE_LOG2   %d\n", Log2(bpb));
 216   fprintf(stream, "#define PR_BITS_PER_SHORT_LOG2  %d\n",
 217           Log2(bpb * sizeof(short)));
 218   fprintf(stream, "#define PR_BITS_PER_INT_LOG2    %d\n",
 219           Log2(bpb * sizeof(int)));
 220   fprintf(stream, "#define PR_BITS_PER_INT64_LOG2  %d\n", 6);
 221   fprintf(stream, "#define PR_BITS_PER_LONG_LOG2   %d\n",
 222           Log2(bpb * sizeof(long)));
 223   fprintf(stream, "#define PR_BITS_PER_FLOAT_LOG2  %d\n",
 224           Log2(bpb * sizeof(float)));
 225   fprintf(stream, "#define PR_BITS_PER_DOUBLE_LOG2 %d\n\n",
 226           Log2(bpb * sizeof(double)));
 227
 228   fprintf(stream, "#define PR_ALIGN_OF_SHORT   %d\n", ALIGN_OF(short));
 229   fprintf(stream, "#define PR_ALIGN_OF_INT     %d\n", ALIGN_OF(int));
 230   fprintf(stream, "#define PR_ALIGN_OF_LONG    %d\n", ALIGN_OF(long));
 231   if (sizeof(INT64) < 8) {
 232     /* this machine doesn't actually support PRInt64's */
 233     fprintf(stream, "#define PR_ALIGN_OF_INT64   %d\n", ALIGN_OF(fakelonglong));
 234   } else {
 235     fprintf(stream, "#define PR_ALIGN_OF_INT64   %d\n", ALIGN_OF(PRInt64));
 236   }
 237   fprintf(stream, "#define PR_ALIGN_OF_FLOAT   %d\n", ALIGN_OF(float));
 238   fprintf(stream, "#define PR_ALIGN_OF_DOUBLE  %d\n", ALIGN_OF(double));
 239   fprintf(stream, "#define PR_ALIGN_OF_POINTER %d\n\n", ALIGN_OF(pointer));
 240
 241   fprintf(stream, "#endif /* nspr_cpucfg___ */\n");
 242   fclose(stream);
 243
 244   return 0;
 245 }