/* check.h: ASSERTION INTERFACE
*
* $Id: //info.ravenbrook.com/project/mps/version/1.104/code/check.h#1 $
* Copyright (c) 2001 Ravenbrook Limited. See end of file for license.
* Portions copyright (C) 2002 Global Graphics Software.
*
* .aver: This header defines a family of AVER and NOTREACHED macros.
* These macros should be used to instrument and annotate code with
* invariants, and so provide both interface and internal consistency
* checks.
*
* .comment: Non-obvious AVER statements should always be accompanied by
* a comment.
*
* .disable: When assertions are disabled, AVER expands to something
* which contains the condition but discards the result. Compilers
* will throw the code away, but check its syntax.
*
* .trans.level-check: CheckLevel itself is not checked anywhere.
*/
#ifndef check_h
#define check_h
#include "config.h"
#include "misc.h"
#include "mpslib.h"
/* CheckLevel -- Control check method behaviour */
extern unsigned CheckLevel;
enum {
CheckNONE = 0,
CheckSHALLOW = 1,
CheckDEEP = 2
};
/* AVER, AVERT -- MPM assertions
*
* AVER and AVERT are used to assert conditions in the code.
*/
#if defined(CHECK_NONE)
#define AVER(cond) DISCARD(cond)
#define AVERT(type, val) DISCARD(type ## Check(val))
#define AVER_CRITICAL(cond) DISCARD(cond)
#define AVERT_CRITICAL(type, val) DISCARD(type ## Check(val))
#elif defined(CHECK)
#define AVER(cond) ASSERT(cond, #cond)
#define AVERT(type, val) ASSERT(type ## Check(val), \
"TypeCheck " #type ": " #val)
#define AVER_CRITICAL(cond) \
BEGIN \
if (CheckLevel != CheckNONE) ASSERT(cond, #cond); \
END
#define AVERT_CRITICAL(type, val) \
BEGIN \
if (CheckLevel != CheckNONE) \
ASSERT(type ## Check(val), "TypeCheck " #type ": " #val); \
END
#else
#error "No checking defined."
#endif
/* internals for actually asserting */
#define ASSERT(cond, condstring) \
BEGIN \
if (cond) NOOP; else \
mps_lib_assert_fail(condstring "\n" __FILE__ "\n" STR(__LINE__)); \
END
/* NOTREACHED -- control should never reach this statement */
#if defined(CHECK)
#define NOTREACHED \
BEGIN \
mps_lib_assert_fail("unreachable code" "\n" __FILE__ "\n" STR(__LINE__)); \
END
#else
#define NOTREACHED NOOP
#endif
/* CHECKT -- check type simply
*
* Must be thread safe. See <design/interface-c/#thread-safety>
* and <design/interface-c/#check.space>.
*/
#define CHECKT(type, val) ((val) != NULL && (val)->sig == type ## Sig)
#if defined(CHECK_NONE)
#define CHECKS(type, val) DISCARD(CHECKT(type, val))
#define CHECKL(cond) DISCARD(cond)
#define CHECKD(type, val) DISCARD(CHECKT(type, val))
#define CHECKD_NOSIG(type, val) DISCARD((val) != NULL)
#define CHECKU(type, val) DISCARD(CHECKT(type, val))
#define CHECKU_NOSIG(type, val) DISCARD((val) != NULL)
#else
/* CHECKS -- Check Signature */
#define CHECKS(type, val) ASSERT(CHECKT(type, val), \
"SigCheck " #type ": " #val)
/* CHECKL -- Check Local Invariant
*
* Could make this an expression using ?:
*/
#define CHECKL(cond) \
BEGIN \
switch(CheckLevel) { \
case CheckNONE: \
NOOP; \
break; \
case CheckSHALLOW: \
case CheckDEEP: \
ASSERT(cond, #cond); \
break; \
} \
END
/* CHECKD -- Check Down */
#define CHECKD(type, val) \
BEGIN \
switch(CheckLevel) { \
case CheckNONE: \
NOOP; \
break; \
case CheckSHALLOW: \
ASSERT(CHECKT(type, val), \
"SigCheck " #type ": " #val); \
break; \
case CheckDEEP: \
ASSERT(type ## Check(val), \
"TypeCheck " #type ": " #val); \
break; \
} \
END
/* CHECKD_NOSIG -- Check Down for a type with no signature */
#define CHECKD_NOSIG(type, val) \
BEGIN \
switch(CheckLevel) { \
case CheckNONE: \
NOOP; \
break; \
case CheckSHALLOW: \
ASSERT((val) != NULL, \
"NullCheck " #type ": " #val); \
break; \
case CheckDEEP: \
ASSERT(type ## Check(val), \
"TypeCheck " #type ": " #val); \
break; \
} \
END
/* CHECKU -- Check Up */
#define CHECKU(type, val) \
BEGIN \
switch(CheckLevel) { \
case CheckNONE: \
NOOP; \
break; \
case CheckSHALLOW: \
case CheckDEEP: \
ASSERT(CHECKT(type, val), \
"SigCheck " #type ": " #val); \
break; \
} \
END
/* CHECKU_NOSIG -- Check Up for a type with no signature */
#define CHECKU_NOSIG(type, val) \
BEGIN \
switch(CheckLevel) { \
case CheckNONE: \
NOOP; \
break; \
case CheckSHALLOW: \
case CheckDEEP: \
ASSERT((val) != NULL, \
"NullCheck " #type ": " #val); \
break; \
} \
END
#endif
/* CHECKLVALUE &c -- type compatibility checking
*
* .check.macros: The CHECK* macros use some C trickery to attempt to
* verify that certain types and fields are equivalent. They do not
* do a complete job. This trickery is justified by the security gained
* in knowing that <code/mps.h> matches the MPM. See also
* mail.richard.1996-08-07.09-49. [This paragraph is intended to
* satisfy rule.impl.trick.]
*/
#define CHECKLVALUE(lv1, lv2) \
((void)sizeof((lv1) = (lv2)), (void)sizeof((lv2) = (lv1)), TRUE)
#define CHECKTYPE(t1, t2) \
(sizeof(t1) == sizeof(t2) && \
CHECKLVALUE(*((t1 *)0), *((t2 *)0)))
#define CHECKFIELDAPPROX(s1, f1, s2, f2) \
(sizeof(((s1 *)0)->f1) == sizeof(((s2 *)0)->f2) && \
offsetof(s1, f1) == offsetof(s2, f2))
#define CHECKFIELD(s1, f1, s2, f2) \
(CHECKFIELDAPPROX(s1, f1, s2, f2) && \
CHECKLVALUE(((s1 *)0)->f1, ((s2 *)0)->f2))
#endif /* check_h */
/* C. COPYRIGHT AND LICENSE
*
* Copyright (C) 2001-2002 Ravenbrook Limited <http://www.ravenbrook.com/>.
* All rights reserved. This is an open source license. Contact
* Ravenbrook for commercial licensing options.
*
* 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.
*
* 3. Redistributions in any form must be accompanied by information on how
* to obtain complete source code for this software and any accompanying
* software that uses this software. The source code must either be
* included in the distribution or be available for no more than the cost
* of distribution plus a nominal fee, and must be freely redistributable
* under reasonable conditions. For an executable file, complete source
* code means the source code for all modules it contains. It does not
* include source code for modules or files that typically accompany the
* major components of the operating system on which the executable file
* runs.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS
* IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
* TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR
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* NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
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