text: /*-
   * Copyright (c) 2006 Verdens Gang AS
   * Copyright (c) 2012 Fastly Inc
   * Copyright (c) 2006-2015 Varnish Software AS
   * All rights reserved.
   *
   * Author: Poul-Henning Kamp <phk@phk.freebsd.dk>
   * Author: Rogier 'DocWilco' Mulhuijzen <rogier@fastly.com>
   *
   * Inspired by FreeBSD's <sys/cdefs.h>
   *
   * SPDX-License-Identifier: BSD-2-Clause
   *
   * Redistribution and use in source and binary forms, with or without
   * modification, are permitted provided that the following conditions
   * are met:
   * 1. Redistributions of source code must retain the above copyright
   *    notice, this list of conditions and the following disclaimer.
   * 2. Redistributions in binary form must reproduce the above copyright
   *    notice, this list of conditions and the following disclaimer in the
   *    documentation and/or other materials provided with the distribution.
   *
   * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
   * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
   * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
   * ARE DISCLAIMED.  IN NO EVENT SHALL AUTHOR OR CONTRIBUTORS BE LIABLE
   * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
   * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
   * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
   * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
   * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
   * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
   * SUCH DAMAGE.
   *
   * Names of the form "v_[a-z_]*_" is reserved for this file.
   *
   * This file should always be the first non <...> include in a .c file.
   */
  
  #include <stddef.h>
  
  #ifdef VDEF_H_INCLUDED
  #  error "vdef.h included multiple times"
  #endif
  #define VDEF_H_INCLUDED
  
  /* Safe printf into a fixed-size buffer */
  #define bprintf(buf, fmt, ...)						\
  	do {								\
  		int ibprintf;						\
  		ibprintf = snprintf(buf, sizeof buf, fmt, __VA_ARGS__);	\
  		assert(ibprintf >= 0 && ibprintf < (int)sizeof buf);	\
  	} while (0)
  
  /* Safe printf into a fixed-size buffer */
  #define vbprintf(buf, fmt, ap)						\
  	do {								\
  		int ivbprintf;						\
  		ivbprintf = vsnprintf(buf, sizeof buf, fmt, ap);	\
  		assert(ivbprintf >= 0 && ivbprintf < (int)sizeof buf);	\
  	} while (0)
  
  /* Safe strcpy into a fixed-size buffer */
  #define bstrcpy(dst, src)						\
  	do {								\
  		assert(strlen(src) + 1 <= sizeof (dst));		\
  		strcpy((dst), (src));					\
  	} while (0)
  
  // TODO #define strcpy BANNED
  // TODO then revert 0fa4baead49f0a45f68d3db0b7743c5e4e93ad4d
  // TODO and replace with flexelint exception
  
  /* Close and discard filedescriptor */
  #define closefd(fdp)				\
  	do {					\
  		assert(*(fdp) >= 0);		\
  		AZ(close(*(fdp)));		\
  		*(fdp) = -1;			\
  	} while (0)
  
  #if !defined(__has_feature)
  #  define __has_feature(x)	0
  #endif
  
  #ifndef __GNUC_PREREQ__
  # if defined __GNUC__ && defined __GNUC_MINOR__
  #  define __GNUC_PREREQ__(maj, min) \
  	(__GNUC__ > (maj) || (__GNUC__ == (maj) && __GNUC_MINOR__ >= (min)))
  # else
  #  define __GNUC_PREREQ__(maj, min) 0
  # endif
  #endif
  
  #if __GNUC_PREREQ__(2, 95) || defined(__INTEL_COMPILER)
  #  define v_printflike_(f,a) __attribute__((format(printf, f, a)))
  #else
  #  define v_printflike_(f,a)
  #endif
  
  #define v_noreturn_ __attribute__((__noreturn__))
  
  #ifdef __GNUC__
  #  define v_deprecated_ __attribute__((deprecated))
  #else
  #  define v_deprecated_
  #endif
  
  #if __GNUC_PREREQ__(4,4) // added 2008-07-23
  #  define v_dont_optimize __attribute__((optimize("O")))
  #else
  #  define v_dont_optimize
  #endif
  
  #ifdef HAVE___GCOV_FLUSH
  #  define v_gcov_flush() __gcov_flush()
  int __gcov_flush(void);
  #elif defined HAVE___GCOV_DUMP
  #  define v_gcov_flush() __gcov_dump()
  void __gcov_dump(void);
  #elif defined HAVE___LLVM_GCOV_FLUSH
  #  define v_gcov_flush() __llvm_gcov_flush()
  int __llvm_gcov_flush(void);
  #else
  #  define v_gcov_flush() do { } while (0)
  #endif
  
  /*********************************************************************
   * Fundamental numerical limits
    * These limits track RFC8941
   * We use hex notation because 999999999999.999 is not perfectly
   * representable in ieee64 doubles.
   */
  
  #define VRT_INTEGER_MAX 999999999999999
  #define VRT_INTEGER_MIN -999999999999999
  #define VRT_DECIMAL_MAX 0x1.d1a94a1fffff8p+39
  #define VRT_DECIMAL_MIN -0x1.d1a94a1fffff8p+39
  
  /*********************************************************************
   * Pointer alignment magic
   */
  
  #if defined(__sparc__)
  /* NB: Overbroad test for 32bit userland on 64bit SPARC cpus. */
  #  define PALGN	    (sizeof(double) - 1)	/* size of alignment */
  #else
  #  define PALGN	    (sizeof(void *) - 1)	/* size of alignment */
  #endif
  #define PAOK(p)	    (((uintptr_t)(p) & PALGN) == 0)	/* is aligned */
  #define PRNDDN(p)   ((uintptr_t)(p) & ~PALGN)		/* Round down */
  #define PRNDUP(p)   (((uintptr_t)(p) + PALGN) & ~PALGN)	/* Round up */
  
  /*********************************************************************
   * To be used as little as possible to wash off const/volatile etc.
   */
  #define TRUST_ME(ptr)	((void*)(uintptr_t)(ptr))
  
  /**********************************************************************
   * Generic power-2 rounding macros
   */
  
  #define PWR2(x)     ((((x)-1UL)&(x))==0)		/* Is a power of two */
  #define RDN2(x, y)  ((x)&(~((uintptr_t)(y)-1UL)))	/* PWR2(y) true */
  #define RUP2(x, y)  (((x)+((y)-1))&(~((uintptr_t)(y)-1UL))) /* PWR2(y) true */
  
  /**********************************************************************
   * Find the minimum or maximum values.
   * Only evaluate the expression once and perform type checking.
   */
  
  /* ref: https://stackoverflow.com/a/17624752 */
  
  #define VINDIRECT(a, b, c)	a ## b ## c
  #define VCOMBINE(a, b, c)	VINDIRECT(a, b, c)
  
  #if defined(__COUNTER__)
  #	define VUNIQ_NAME(base)	VCOMBINE(base, __LINE__, __COUNTER__)
  #else
  #	define VUNIQ_NAME(base)	VCOMBINE(base, __LINE__, 0)
  #endif
  
  /* ref: https://gcc.gnu.org/onlinedocs/gcc/Typeof.html */
  
  #define _vmin(a, b, _va, _vb)						\
  ({									\
  	typeof (a) _va = (a);						\
  	typeof (b) _vb = (b);						\
  	(void)(&_va == &_vb);						\
  	_va < _vb ? _va : _vb;						\
  })
  
  #define _vmax(a, b, _va, _vb)						\
  ({									\
  	typeof (a) _va = (a);						\
  	typeof (b) _vb = (b);						\
  	(void)(&_va == &_vb);						\
  	_va > _vb ? _va : _vb;						\
  })
  
  #define vmin(a, b)		_vmin((a), (b), VUNIQ_NAME(_vmina),	\
      VUNIQ_NAME(_vminb))
  #define vmax(a, b)		_vmax((a), (b), VUNIQ_NAME(_vmaxa),	\
      VUNIQ_NAME(_vmaxb))
  
  #define vmin_t(type, a, b)	vmin((type)(a), (type)(b))
  #define vmax_t(type, a, b)	vmax((type)(a), (type)(b))
  
  /**********************************************************************
   * Clamp the value between two limits.
   */
  
  #define vlimit(a, l, u)		vmax((l), vmin((a), (u)))
  #define vlimit_t(type, a, l, u)	vmax_t(type, (l), vmin_t(type, (a), (u)))
  
  /**********************************************************************
   * FlexeLint and compiler shutuppery
   */
  
  /*
   * In OO-light situations, functions have to match their prototype
   * even if that means not const'ing a const'able argument.
   * The typedef should be specified as argument to the macro.
   */
  #define v_matchproto_(xxx)		/*lint --e{818} */
  
  /*
   * State variables may change value before we have considered the
   * previous value
   */
  #define v_statevariable_(varname)	varname /*lint -esym(838,varname) */
  
  #ifdef __SUNPRO_C
  #  define NEEDLESS(s)		{}
  #else
  #  define NEEDLESS(s)		s
  #endif
  
  #if __GNUC_PREREQ__(2, 7)
  #  define v_unused_ __attribute__((__unused__))
  #else
  #  define v_unused_
  #endif
  
  /* VTIM API overhaul WIP */
  typedef double vtim_mono;
  typedef double vtim_real;
  typedef double vtim_dur;
  
  /**********************************************************************
   * txt (vas.h needed for the macros)
   */
  
  typedef struct {
  	const char		*b;
  	const char		*e;
  } txt;
  
  #define Tcheck(t)	do { (void)pdiff((t).b, (t).e); } while (0)
  #define Tlen(t)		(pdiff((t).b, (t).e))
  