lib/ack/libm2/ucheck.c

   1 /*
   2  * (c) copyright 1988 by the Vrije Universiteit, Amsterdam, The Netherlands.
   3  * See the copyright notice in the ACK home directory, in the file "Copyright".
   4  *
   5  *
   6  * Module:      CARDINAL operations with overflow checking
   7  * Author:      Ceriel J.H. Jacobs
   8  * Version:     $Header$
   9 */
  10
  11 #ifndef EM_WSIZE
  12 #define EM_WSIZE _EM_WSIZE
  13 #endif
  14 #ifndef EM_LSIZE
  15 #define EM_LSIZE _EM_LSIZE
  16 #endif
  17
  18 #include <m2_traps.h>
  19
  20 #define MAXCARD ((unsigned)-1)
  21 #if EM_WSIZE < EM_LSIZE
  22 #define MAXLONGCARD     ((unsigned long) -1L)
  23 #endif
  24
  25 adduchk(a,b)
  26   unsigned      a,b;
  27 {
  28   if (MAXCARD - a < b) TRP(M2_UOVFL);
  29 }
  30
  31 #if EM_WSIZE < EM_LSIZE
  32 addulchk(a,b)
  33   unsigned long a,b;
  34 {
  35   if (MAXLONGCARD - a < b) TRP(M2_UOVFL);
  36 }
  37 #endif
  38
  39 muluchk(a,b)
  40   unsigned      a,b;
  41 {
  42   if (a != 0 && MAXCARD/a < b) TRP(M2_UOVFL);
  43 }
  44
  45 #if EM_WSIZE < EM_LSIZE
  46 mululchk(a,b)
  47   unsigned long a,b;
  48 {
  49   if (a != 0 && MAXLONGCARD/a < b) TRP(M2_UOVFL);
  50 }
  51 #endif
  52
  53 subuchk(a,b)
  54   unsigned      a,b;
  55 {
  56   if (b < a) TRP(M2_UUVFL);
  57 }
  58
  59 #if EM_WSIZE < EM_LSIZE
  60 subulchk(a,b)
  61   unsigned long a,b;
  62 {
  63   if (b < a) TRP(M2_UUVFL);
  64 }
  65 #endif