msdos/tailor.c

   1 /* tailor.c -- target dependent functions
   2  * Copyright (C) 1992-1993 Jean-loup Gailly
   3  * This is free software; you can redistribute it and/or modify it under the
   4  * terms of the GNU General Public License, see the file COPYING.
   5  */
   6
   7 /* tailor.c is a bunch of non portable routines.
   8  * It should be kept to a minimum.
   9  */
  10
  11 #include <config.h>
  12 #include "tailor.h"
  13 #include "gzip.h"
  14
  15 #ifdef __TURBOC__
  16
  17 /************************/
  18 /*  Function fcalloc()  */
  19 /************************/
  20
  21 /* Turbo C malloc() does not allow dynamic allocation of 64K bytes
  22  * and farmalloc(64K) returns a pointer with an offset of 8, so we
  23  * must fix the pointer. Warning: the pointer must be put back to its
  24  * original form in order to free it, use fcfree().
  25  * For MSC, use halloc instead of this function (see tailor.h).
  26  */
  27 static ush ptr_offset = 0;
  28
  29 void * fcalloc(items, size)
  30     unsigned items; /* number of items */
  31     unsigned size;  /* item size */
  32 {
  33     void * buf = farmalloc((ulg)items*size + 16L);
  34     if (buf == NULL) return NULL;
  35     /* Normalize the pointer to seg:0 */
  36     if (ptr_offset == 0) {
  37         ptr_offset = (ush)((uch*)buf-0);
  38     } else if (ptr_offset != (ush)((uch*)buf-0)) {
  39         error(_("inconsistent ptr_offset"));
  40     }
  41     *((ush*)&buf+1) += (ptr_offset + 15) >> 4;
  42     *(ush*)&buf = 0;
  43     return buf;
  44 }
  45
  46 void fcfree(ptr)
  47     void *ptr; /* region allocated with fcalloc() */
  48 {
  49     /* Put the pointer back to its original form: */
  50     *((ush*)&ptr+1) -= (ptr_offset + 15) >> 4;
  51     *(ush*)&ptr = ptr_offset;
  52     farfree(ptr);
  53  }
  54
  55 #endif /* __TURBOC__ */