mkrounding.c

   1 /*
   2  * A pre-compilation helper program to aid in the creation of rounding.h.
   3  *
   4  * Copyright (C) 2007 Wayne Davison
   5  *
   6  * This program is free software; you can redistribute it and/or modify
   7  * it under the terms of the GNU General Public License as published by
   8  * the Free Software Foundation; either version 3 of the License, or
   9  * (at your option) any later version.
  10  *
  11  * This program is distributed in the hope that it will be useful,
  12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14  * GNU General Public License for more details.
  15  *
  16  * You should have received a copy of the GNU General Public License along
  17  * with this program; if not, visit the http://fsf.org website.
  18  */
  19
  20 #include "rsync.h"
  21
  22 struct test1 {
  23     union file_extras extras1[1];
  24     struct {
  25 #       include "mkrounding.h"
  26     } file;
  27 };
  28
  29 struct test2 {
  30     union file_extras extras2[2];
  31     struct {
  32 #       include "mkrounding.h"
  33     } file;
  34 };
  35
  36 struct test4 {
  37     union file_extras extras4[4];
  38     struct {
  39 #       include "mkrounding.h"
  40     } file;
  41 };
  42
  43 #define SIZE_TEST(n) (sizeof (struct test ## n) == EXTRA_LEN * n + sizeof (struct file_struct))
  44
  45  int main(UNUSED(int argc), UNUSED(char *argv[]))
  46 {
  47     int cnt;
  48     if (SIZE_TEST(1))
  49         cnt = 0;
  50     else if (SIZE_TEST(2))
  51         cnt = 1;
  52     else if (SIZE_TEST(4))
  53         cnt = 3;
  54     else {
  55         fprintf(stderr, "Unable to determine required file_extras rounding!\n");
  56         cnt = 3;
  57     }
  58     if (cnt)
  59         fprintf(stderr, "Rounding file_extras in multiples of %d", cnt + 1);
  60     else
  61         fprintf(stderr, "No rounding needed for file_extras");
  62     fprintf(stderr, " (EXTRA_LEN=%d, FILE_STRUCT_LEN=%d)\n",
  63             (int)EXTRA_LEN, (int)FILE_STRUCT_LEN);
  64     printf("#define EXTRA_ROUNDING %d\n", cnt);
  65     return 0;
  66 }