#ifndef RANGE_H

/* Definitions of helper functions and macros to create expressions
   in a specified range.  Not all the symbols declared here are
   defined.  */

#define SIZE_MAX __SIZE_MAX__
#define DIFF_MAX __PTRDIFF_MAX__
#define DIFF_MIN (-DIFF_MAX - 1)

typedef __INT32_TYPE__   int32_t;
typedef __PTRDIFF_TYPE__ ptrdiff_t;
typedef __SIZE_TYPE__    size_t;

static inline ptrdiff_t signed_value (void)
{
  extern volatile ptrdiff_t signed_value_source;
  return signed_value_source;
}

static inline size_t unsigned_value (void)
{
  extern volatile size_t unsigned_value_source;
  return unsigned_value_source;
}

static inline ptrdiff_t signed_range (ptrdiff_t min, ptrdiff_t max)
{
  ptrdiff_t val = signed_value ();
  return val < min || max < val ? min : val;
}

static inline ptrdiff_t signed_anti_range (ptrdiff_t min, ptrdiff_t max)
{
  ptrdiff_t val = signed_value ();
  return min <= val && val <= max ? min == DIFF_MIN ? max + 1 : min - 1 : val;
}

static inline size_t unsigned_range (size_t min, size_t max)
{
  size_t val = unsigned_value ();
  return val < min || max < val ? min : val;
}

static inline size_t unsigned_anti_range (size_t min, size_t max)
{
  size_t val = unsigned_value ();
  return min <= val && val <= max ? min == 0 ? max + 1 : min - 1 : val;
}

#define SR(min, max) signed_range ((min), (max))
#define UR(min, max) unsigned_range ((min), (max))

#define SAR(min, max) signed_anti_range ((min), (max))
#define UAR(min, max) unsigned_anti_range ((min), (max))

#endif /* RANGE_H */