[bpt/guile.git] / libguile / __scm.h

/* classes: h_files */

#ifndef __SCMH
#define __SCMH
/*	Copyright (C) 1995, 1996, 1998, 1999 Free Software Foundation, Inc.
 * 
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2, or (at your option)
 * any later version.
 * 
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 * 
 * You should have received a copy of the GNU General Public License
 * along with this software; see the file COPYING.  If not, write to
 * the Free Software Foundation, Inc., 59 Temple Place, Suite 330,
 * Boston, MA 02111-1307 USA
 *
 * As a special exception, the Free Software Foundation gives permission
 * for additional uses of the text contained in its release of GUILE.
 *
 * The exception is that, if you link the GUILE library with other files
 * to produce an executable, this does not by itself cause the
 * resulting executable to be covered by the GNU General Public License.
 * Your use of that executable is in no way restricted on account of
 * linking the GUILE library code into it.
 *
 * This exception does not however invalidate any other reasons why
 * the executable file might be covered by the GNU General Public License.
 *
 * This exception applies only to the code released by the
 * Free Software Foundation under the name GUILE.  If you copy
 * code from other Free Software Foundation releases into a copy of
 * GUILE, as the General Public License permits, the exception does
 * not apply to the code that you add in this way.  To avoid misleading
 * anyone as to the status of such modified files, you must delete
 * this exception notice from them.
 *
 * If you write modifications of your own for GUILE, it is your choice
 * whether to permit this exception to apply to your modifications.
 * If you do not wish that, delete this exception notice.  */
\f
/* {Supported Options}
 *
 * These may be defined or undefined.
 */

/* #define GUILE_DEBUG_FREELIST */

/* If the compile FLAG `SCM_CAUTIOUS' is #defined then the number of
 * arguments is always checked for application of closures.  If the
 * compile FLAG `SCM_RECKLESS' is #defined then they are not checked.
 * Otherwise, number of argument checks for closures are made only when
 * the function position (whose value is the closure) of a combination is
 * not an ILOC or GLOC.  When the function position of a combination is a
 * symbol it will be checked only the first time it is evaluated because
 * it will then be replaced with an ILOC or GLOC.
 */
#undef SCM_RECKLESS
#define SCM_CAUTIOUS

/* After looking up a local for the first time, rewrite the
 * code graph, caching its position.
 */
#define MEMOIZE_LOCALS

/* All the number support there is.
 */
#define SCM_FLOATS
#define BIGNUMS

/* GC should relinquish empty cons-pair arenas. 
 */
#define GC_FREE_SEGMENTS

/* Provide a scheme-accessible count-down timer that
 * generates a pseudo-interrupt.
 */
#define TICKS


/* Use engineering notation when converting numbers strings?
 */
#undef ENGNOT

#undef SCM_CAREFUL_INTS
\f
/* {Unsupported Options}
 *
 * These must be defined as given here.
 */


#define CCLO

/* Guile Scheme supports the #f/() distinction; Guile Lisp won't.  We
   have horrible plans for their unification.  */
#undef SICP

\f

/* Random options (not yet supported or in final form). */

#define STACK_CHECKING
#undef NO_CEVAL_STACK_CHECKING

/* Some auto-generated .h files contain unused prototypes
 * that need these typedefs.
 */
typedef long long long_long;
typedef unsigned long long ulong_long;


\f
/* What did the configure script discover about the outside world?  */
#include "libguile/scmconfig.h"

\f
/* Write prototype declarations like this:
     int foo SCM_P ((int a, int b));
   At definitions, use K&R style declarations, but make sure there's a
   declarative prototype (as above) in scope.  This will give you
   argument type checking, when available, and be harmless otherwise.  */
#ifdef __STDC__
#  define SCM_P(x) x
#else
#  define SCM_P(x) ()
#endif

\f

/* Define
 *
 * SCM_CHAR_CODE_LIMIT		== UCHAR_MAX + 1
 * SCM_MOST_POSITIVE_FIXNUM 	(LONG_MAX>>2)
 * SCM_MOST_NEGATIVE_FIXNUM 	== SCM_SRS((long)LONG_MIN, 2)
 */

#ifdef HAVE_LIMITS_H
# include <limits.h>
# ifdef UCHAR_MAX
#  define SCM_CHAR_CODE_LIMIT (UCHAR_MAX+1L)
# else
#  define SCM_CHAR_CODE_LIMIT 256L
# endif /* def UCHAR_MAX */
# define SCM_MOST_POSITIVE_FIXNUM (LONG_MAX>>2)
# ifdef _UNICOS			/* Stupid cray bug */
#  define SCM_MOST_NEGATIVE_FIXNUM ((long)LONG_MIN/4)
# else
#  define SCM_MOST_NEGATIVE_FIXNUM SCM_SRS((long)LONG_MIN, 2)
# endif				/* UNICOS */
#else
# define SCM_CHAR_CODE_LIMIT 256L
# define SCM_MOST_POSITIVE_FIXNUM ((long)((unsigned long)~0L>>3))
# if (0 != ~0)
#  define SCM_MOST_NEGATIVE_FIXNUM (-SCM_MOST_POSITIVE_FIXNUM-1)
# else
#  define SCM_MOST_NEGATIVE_FIXNUM (-SCM_MOST_POSITIVE_FIXNUM)
# endif /*  (0 != ~0) */
#endif /* def HAVE_LIMITS_H */
\f

#ifdef STDC_HEADERS
# include <stdlib.h>
# ifdef AMIGA
#  include <stddef.h>
# endif /* def AMIGA */
# define scm_sizet size_t
#else
# ifdef _SIZE_T
#  define scm_sizet size_t
# else
#  define scm_sizet unsigned int
# endif /* def _SIZE_T */
#endif /* def STDC_HEADERS */

\f

#include "libguile/tags.h"

\f
#ifdef vms
# ifndef CHEAP_CONTINUATIONS
   typedef int jmp_buf[17];
   extern int setjump(jmp_buf env);
   extern int longjump(jmp_buf env, int ret);
#  define setjmp setjump
#  define longjmp longjump
# else
#  include <setjmp.h>
# endif
#else				/* ndef vms */
# ifdef _CRAY1
    typedef int jmp_buf[112];
    extern int setjump(jmp_buf env);
    extern int longjump(jmp_buf env, int ret);
#  define setjmp setjump
#  define longjmp longjump
# else				/* ndef _CRAY1 */
#  include <setjmp.h>
# endif				/* ndef _CRAY1 */
#endif				/* ndef vms */

/* James Clark came up with this neat one instruction fix for
 * continuations on the SPARC.  It flushes the register windows so
 * that all the state of the process is contained in the stack. 
 */

#ifdef sparc
# define SCM_FLUSH_REGISTER_WINDOWS asm("ta 3")
#else
# define SCM_FLUSH_REGISTER_WINDOWS /* empty */
#endif

/* If stack is not longword aligned then 
 */

/* #define SHORT_ALIGN */
#ifdef THINK_C
# define SHORT_ALIGN
#endif
#ifdef MSDOS
# define SHORT_ALIGN
#endif
#ifdef atarist
# define SHORT_ALIGN
#endif

#ifdef SHORT_ALIGN
typedef short SCM_STACKITEM;
#else
typedef long SCM_STACKITEM;
#endif
\f

#ifndef USE_THREADS
#define SCM_THREAD_DEFER
#define SCM_THREAD_ALLOW
#define SCM_THREAD_REDEFER
#define SCM_THREAD_REALLOW_1
#define SCM_THREAD_REALLOW_2
#define SCM_THREAD_SWITCHING_CODE
#endif

extern unsigned int scm_async_clock;

#define SCM_ASYNC_TICK \
do { \
  if (0 == --scm_async_clock) \
    scm_async_click (); \
} while(0)

#ifdef SCM_CAREFUL_INTS
#define SCM_CHECK_NOT_DISABLED \
  if (scm_ints_disabled) \
    fputs("ints already disabled\n", stderr); \

#define SCM_CHECK_NOT_ENABLED \
  if (!scm_ints_disabled) \
    fputs("ints already enabled\n", stderr); \

#else
#define SCM_CHECK_NOT_DISABLED
#define SCM_CHECK_NOT_ENABLED
#endif


/* Anthony Green writes:
   When the compiler sees...
	   DEFER_INTS;
	   [critical code here]
	   ALLOW_INTS;
   ...it doesn't actually promise to keep the critical code within the
   boundries of the DEFER/ALLOW_INTS instructions. It may very well
   schedule it outside of the magic defined in those macros.

   However, GCC's volatile asm feature forms a barrier over which code is
   never moved. So if you add...
	   asm ("");
   ...to each of the DEFER_INTS and ALLOW_INTS macros, the critical
   code will always remain in place.  asm's without inputs or outputs
   are implicitly volatile. */
#ifdef __GNUC__
#define SCM_FENCE asm /* volatile */ ("")
#else
#define SCM_FENCE
#endif

#define SCM_DEFER_INTS \
do { \
  SCM_FENCE; \
  SCM_CHECK_NOT_DISABLED; \
  SCM_THREAD_DEFER; \
  SCM_FENCE; \
  scm_ints_disabled = 1; \
  SCM_FENCE; \
} while (0)


#define SCM_ALLOW_INTS_ONLY \
do { \
  SCM_THREAD_ALLOW; \
  scm_ints_disabled = 0; \
} while (0)


#define SCM_ALLOW_INTS \
do { \
  SCM_FENCE; \
  SCM_CHECK_NOT_ENABLED; \
  SCM_THREAD_SWITCHING_CODE; \
  SCM_FENCE; \
  scm_ints_disabled = 0; \
  SCM_FENCE; \
  SCM_THREAD_ALLOW; \
  SCM_ASYNC_TICK; \
  SCM_FENCE; \
} while (0)


#define SCM_REDEFER_INTS  \
do { \
  SCM_FENCE; \
  SCM_THREAD_REDEFER; \
  ++scm_ints_disabled; \
  SCM_FENCE; \
} while (0)


#define SCM_REALLOW_INTS \
do { \
  SCM_FENCE; \
  SCM_THREAD_REALLOW_1; \
  SCM_THREAD_SWITCHING_CODE; \
  SCM_FENCE; \
  --scm_ints_disabled; \
  if (!scm_ints_disabled) \
    { \
      SCM_THREAD_REALLOW_2; \
      SCM_ASYNC_TICK; \
    } \
  SCM_FENCE; \
} while (0)


#define SCM_TICK \
do { \
  SCM_DEFER_INTS; \
  SCM_ALLOW_INTS; \
} while (0)

\f

/* Classification of critical sections
 *
 * When Guile moves to POSIX threads, it won't be possible to prevent
 * context switching.  In fact, the whole idea of context switching is
 * bogus if threads are run by different processors.  Therefore, we
 * must ultimately eliminate all critical sections or enforce them by
 * use of mutecis.
 *
 * All instances of SCM_DEFER_INTS and SCM_ALLOW_INTS should therefore
 * be classified and replaced by one of the delimiters below.  If you
 * understand what this is all about, I'd like to encourage you to
 * help with this task.  The set of classes below must of course be
 * incrementally augmented.
 *
 * MDJ 980419 <djurfeldt@nada.kth.se>
 */

/* A sections
 *
 * Allocation of a cell with type tag in the CAR.
 *
 * With POSIX threads, each thread will have a private pool of free
 * cells.  Therefore, this type of section can be removed.  But!  It
 * is important that the CDR is initialized first (with the CAR still
 * indicating a free cell) so that we can guarantee a consistent heap
 * at all times.
 */

#ifdef SCM_POSIX_THREADS
#define SCM_ENTER_A_SECTION
#define SCM_EXIT_A_SECTION
#else
#define SCM_ENTER_A_SECTION SCM_DEFER_INTS
#define SCM_EXIT_A_SECTION SCM_ALLOW_INTS
#endif

\f

/** SCM_ASSERT
 ** 
 **/


#ifdef SCM_RECKLESS
#define SCM_ASSERT(_cond, _arg, _pos, _subr)
#define SCM_ASRTGO(_cond, _label)
#else
#define SCM_ASSERT(_cond, _arg, _pos, _subr) \
	if (!(_cond)) \
          scm_wta(_arg, (char *)(_pos), _subr)
#define SCM_ASRTGO(_cond, _label) \
        if (!(_cond)) \
          goto _label
#endif

/*
 * SCM_WTA_DISPATCH
 */

extern SCM scm_call_generic_0 (SCM gf);

#define SCM_WTA_DISPATCH_0(gf, arg, pos, subr) \
  return ((gf) \
          ? scm_call_generic_0 ((gf)) \
          : scm_wta ((arg), (char *) (pos), (subr)))
#define SCM_GASSERT0(cond, gf, arg, pos, subr) \
  if (!(cond)) SCM_WTA_DISPATCH_0((gf), (arg), (pos), (subr))

extern SCM scm_call_generic_1 (SCM gf, SCM a1);

#define SCM_WTA_DISPATCH_1(gf, a1, pos, subr) \
  return ((gf) \
          ? scm_call_generic_1 ((gf), (a1)) \
          : scm_wta ((a1), (char *) (pos), (subr)))
#define SCM_GASSERT1(cond, gf, a1, pos, subr) \
  if (!(cond)) SCM_WTA_DISPATCH_1((gf), (a1), (pos), (subr))

extern SCM scm_call_generic_2 (SCM gf, SCM a1, SCM a2);

#define SCM_WTA_DISPATCH_2(gf, a1, a2, pos, subr) \
  return ((gf) \
          ? scm_call_generic_2 ((gf), (a1), (a2)) \
          : scm_wta ((pos) == SCM_ARG1 ? (a1) : (a2), (char *) (pos), (subr)))
#define SCM_GASSERT2(cond, gf, a1, a2, pos, subr) \
  if (!(cond)) SCM_WTA_DISPATCH_2((gf), (a1), (a2), (pos), (subr))

extern SCM scm_apply_generic (SCM gf, SCM args);

#define SCM_WTA_DISPATCH_n(gf, args, pos, subr) \
  return ((gf) \
          ? scm_apply_generic ((gf), (args)) \
          : scm_wta (scm_list_ref ((args), SCM_MAKINUM ((pos) - 1)), \
		     (char *) (pos), \
		     (subr)))
#define SCM_GASSERTn(cond, gf, args, pos, subr) \
  if (!(cond)) SCM_WTA_DISPATCH_n((gf), (args), (pos), (subr))

#ifndef SCM_MAGIC_SNARFER
/* Let these macros pass through if
   we are snarfing;  thus we can tell the
   difference between the use of an actual
   number vs. the use of one of these macros --
   actual numbers in SCM_VALIDATE_* and SCM_ASSERT
   constructs must match the formal argument name,
   but using SCM_ARG* avoids the test */

#define SCM_ARGn 		0
#define SCM_ARG1 		1
#define SCM_ARG2 		2
#define SCM_ARG3 		3
#define SCM_ARG4 		4
#define SCM_ARG5 		5
#define SCM_ARG6 		6
#define SCM_ARG7 		7 
     /* #define SCM_ARGERR(X) 		((X) < SCM_WNA \
				 ? (char *)(X) \
				 : "wrong type argument")
				 */

/* Following must match entry indexes in scm_errmsgs[].
 * Also, SCM_WNA must follow the last SCM_ARGn in sequence.
 */
#define SCM_WNA 		8
     /* #define SCM_OVSCM_FLOW 		9 */
#define SCM_OUTOFRANGE 		10
#define SCM_NALLOC 		11
     /* #define SCM_STACK_OVFLOW	12 */
     /* #define SCM_EXIT 		13 */

#endif /* SCM_MAGIC_SNARFER */

/* (...still matching scm_errmsgs)  These
 * are signals.  Signals may become errors
 * but are distinguished because they first
 * try to invoke a handler that can resume
 * the interrupted routine.
 */
#define SCM_HUP_SIGNAL 		14
#define SCM_INT_SIGNAL 		15
#define SCM_FPE_SIGNAL 		16
#define SCM_BUS_SIGNAL 		17
#define SCM_SEGV_SIGNAL 	18
#define SCM_ALRM_SIGNAL 	19
#define SCM_GC_SIGNAL		20
#define SCM_TICK_SIGNAL		21

#define SCM_SIG_ORD(X)		((X) - SCM_HUP_SIGNAL)
#define SCM_ORD_SIG(X)		((X) + SCM_HUP_SIGNAL)
#define SCM_NUM_SIGS		(SCM_SIG_ORD (SCM_TICK_SIGNAL) + 1)

#if 0
struct errdesc
{
  char *msg;
  char *s_response;
  short parent_err;
};


extern struct errdesc scm_errmsgs[];
#endif

\f

/* SCM_EXIT_SUCCESS is the default code to return from SCM if no errors
 * were encountered.  SCM_EXIT_FAILURE is the default code to return from
 * SCM if errors were encountered.  The return code can be explicitly
 * specified in a SCM program with (scm_quit <n>).
 */

#ifndef SCM_EXIT_SUCCESS
#ifdef vms
#define SCM_EXIT_SUCCESS 1
#else
#define SCM_EXIT_SUCCESS 0
#endif /* def vms */
#endif /* ndef SCM_EXIT_SUCCESS */
#ifndef SCM_EXIT_FAILURE
#ifdef vms
#define SCM_EXIT_FAILURE 2
#else
#define SCM_EXIT_FAILURE 1
#endif /* def vms */
#endif /* ndef SCM_EXIT_FAILURE */


\f

#endif  /* __SCMH */
Commit	Line	Data
0f2d19dd JB	1	/* classes: h_files */
	2
	3	#ifndef __SCMH
	4	#define __SCMH
78a0461a	5	/* Copyright (C) 1995, 1996, 1998, 1999 Free Software Foundation, Inc.
0f2d19dd JB	6	*
	7	* This program is free software; you can redistribute it and/or modify
	8	* it under the terms of the GNU General Public License as published by
	9	* the Free Software Foundation; either version 2, or (at your option)
	10	* any later version.
	11	*
	12	* This program is distributed in the hope that it will be useful,
	13	* but WITHOUT ANY WARRANTY; without even the implied warranty of
	14	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
	15	* GNU General Public License for more details.
	16	*
	17	* You should have received a copy of the GNU General Public License
	18	* along with this software; see the file COPYING. If not, write to
82892bed JB	19	* the Free Software Foundation, Inc., 59 Temple Place, Suite 330,
82892bed JB	20	* Boston, MA 02111-1307 USA
0f2d19dd JB	21	*
	22	* As a special exception, the Free Software Foundation gives permission
	23	* for additional uses of the text contained in its release of GUILE.
	24	*
	25	* The exception is that, if you link the GUILE library with other files
	26	* to produce an executable, this does not by itself cause the
	27	* resulting executable to be covered by the GNU General Public License.
	28	* Your use of that executable is in no way restricted on account of
	29	* linking the GUILE library code into it.
	30	*
	31	* This exception does not however invalidate any other reasons why
	32	* the executable file might be covered by the GNU General Public License.
	33	*
	34	* This exception applies only to the code released by the
	35	* Free Software Foundation under the name GUILE. If you copy
	36	* code from other Free Software Foundation releases into a copy of
	37	* GUILE, as the General Public License permits, the exception does
	38	* not apply to the code that you add in this way. To avoid misleading
	39	* anyone as to the status of such modified files, you must delete
	40	* this exception notice from them.
	41	*
	42	* If you write modifications of your own for GUILE, it is your choice
	43	* whether to permit this exception to apply to your modifications.
82892bed	44	* If you do not wish that, delete this exception notice. */
0f2d19dd JB	45	\f
	46	/* {Supported Options}
	47	*
	48	* These may be defined or undefined.
	49	*/
	50
70d63753 GB	51	/* #define GUILE_DEBUG_FREELIST */
70d63753 GB	52
cf7c17e9	53	/* If the compile FLAG `SCM_CAUTIOUS' is #defined then the number of
0f2d19dd	54	* arguments is always checked for application of closures. If the
cf7c17e9	55	* compile FLAG `SCM_RECKLESS' is #defined then they are not checked.
0f2d19dd JB	56	* Otherwise, number of argument checks for closures are made only when
	57	* the function position (whose value is the closure) of a combination is
	58	* not an ILOC or GLOC. When the function position of a combination is a
	59	* symbol it will be checked only the first time it is evaluated because
	60	* it will then be replaced with an ILOC or GLOC.
	61	*/
cf7c17e9 JB	62	#undef SCM_RECKLESS
cf7c17e9 JB	63	#define SCM_CAUTIOUS
0f2d19dd JB	64
	65	/* After looking up a local for the first time, rewrite the
	66	* code graph, caching its position.
	67	*/
	68	#define MEMOIZE_LOCALS
	69
	70	/* All the number support there is.
	71	*/
	72	#define SCM_FLOATS
	73	#define BIGNUMS
	74
	75	/* GC should relinquish empty cons-pair arenas.
	76	*/
	77	#define GC_FREE_SEGMENTS
	78
	79	/* Provide a scheme-accessible count-down timer that
	80	* generates a pseudo-interrupt.
	81	*/
	82	#define TICKS
	83
	84
	85	/* Use engineering notation when converting numbers strings?
	86	*/
	87	#undef ENGNOT
	88
0f2d19dd JB	89	#undef SCM_CAREFUL_INTS
	90	\f
	91	/* {Unsupported Options}
	92	*
3c205827	93	* These must be defined as given here.
0f2d19dd JB	94	*/
	95
	96
	97	#define CCLO
3c205827 JB	98
	99	/* Guile Scheme supports the #f/() distinction; Guile Lisp won't. We
	100	have horrible plans for their unification. */
	101	#undef SICP
0f2d19dd JB	102
	103	\f
	104
80c78696	105	/* Random options (not yet supported or in final form). */
0f2d19dd	106
80c78696 MD	107	#define STACK_CHECKING
80c78696 MD	108	#undef NO_CEVAL_STACK_CHECKING
0f2d19dd JB	109
	110	/* Some auto-generated .h files contain unused prototypes
	111	* that need these typedefs.
	112	*/
afe5177e GH	113	typedef long long long_long;
afe5177e GH	114	typedef unsigned long long ulong_long;
0f2d19dd JB	115
	116
	117	\f
b971d089	118	/* What did the configure script discover about the outside world? */
2a1d8241	119	#include "libguile/scmconfig.h"
b971d089 JB	120
	121	\f
	122	/* Write prototype declarations like this:
3e8a29f5	123	int foo SCM_P ((int a, int b));
b971d089 JB	124	At definitions, use K&R style declarations, but make sure there's a
	125	declarative prototype (as above) in scope. This will give you
	126	argument type checking, when available, and be harmless otherwise. */
	127	#ifdef __STDC__
3e8a29f5	128	# define SCM_P(x) x
b971d089	129	#else
72713b2f	130	# define SCM_P(x) ()
b971d089 JB	131	#endif
	132
	133	\f
0f2d19dd JB	134
	135	/* Define
	136	*
e2806c10	137	* SCM_CHAR_CODE_LIMIT == UCHAR_MAX + 1
0f2d19dd JB	138	* SCM_MOST_POSITIVE_FIXNUM (LONG_MAX>>2)
	139	* SCM_MOST_NEGATIVE_FIXNUM == SCM_SRS((long)LONG_MIN, 2)
	140	*/
	141
b971d089	142	#ifdef HAVE_LIMITS_H
0f2d19dd JB	143	# include <limits.h>
0f2d19dd JB	144	# ifdef UCHAR_MAX
e2806c10	145	# define SCM_CHAR_CODE_LIMIT (UCHAR_MAX+1L)
0f2d19dd	146	# else
e2806c10	147	# define SCM_CHAR_CODE_LIMIT 256L
0f2d19dd JB	148	# endif /* def UCHAR_MAX */
	149	# define SCM_MOST_POSITIVE_FIXNUM (LONG_MAX>>2)
	150	# ifdef _UNICOS /* Stupid cray bug */
	151	# define SCM_MOST_NEGATIVE_FIXNUM ((long)LONG_MIN/4)
	152	# else
	153	# define SCM_MOST_NEGATIVE_FIXNUM SCM_SRS((long)LONG_MIN, 2)
	154	# endif /* UNICOS */
	155	#else
e2806c10	156	# define SCM_CHAR_CODE_LIMIT 256L
0f2d19dd JB	157	# define SCM_MOST_POSITIVE_FIXNUM ((long)((unsigned long)~0L>>3))
	158	# if (0 != ~0)
	159	# define SCM_MOST_NEGATIVE_FIXNUM (-SCM_MOST_POSITIVE_FIXNUM-1)
	160	# else
	161	# define SCM_MOST_NEGATIVE_FIXNUM (-SCM_MOST_POSITIVE_FIXNUM)
	162	# endif /* (0 != ~0) */
b971d089	163	#endif /* def HAVE_LIMITS_H */
0f2d19dd JB	164	\f
0f2d19dd JB	165
2a1d8241 JB	166	#ifdef STDC_HEADERS
	167	# include <stdlib.h>
	168	# ifdef AMIGA
	169	# include <stddef.h>
	170	# endif /* def AMIGA */
	171	# define scm_sizet size_t
	172	#else
	173	# ifdef _SIZE_T
	174	# define scm_sizet size_t
	175	# else
	176	# define scm_sizet unsigned int
	177	# endif /* def _SIZE_T */
	178	#endif /* def STDC_HEADERS */
	179
	180	\f
	181
	182	#include "libguile/tags.h"
0f2d19dd JB	183
	184	\f
	185	#ifdef vms
	186	# ifndef CHEAP_CONTINUATIONS
	187	typedef int jmp_buf[17];
	188	extern int setjump(jmp_buf env);
	189	extern int longjump(jmp_buf env, int ret);
	190	# define setjmp setjump
	191	# define longjmp longjump
	192	# else
	193	# include <setjmp.h>
	194	# endif
	195	#else /* ndef vms */
	196	# ifdef _CRAY1
	197	typedef int jmp_buf[112];
	198	extern int setjump(jmp_buf env);
	199	extern int longjump(jmp_buf env, int ret);
	200	# define setjmp setjump
	201	# define longjmp longjump
	202	# else /* ndef _CRAY1 */
	203	# include <setjmp.h>
	204	# endif /* ndef _CRAY1 */
	205	#endif /* ndef vms */
	206
0f2d19dd JB	207	/* James Clark came up with this neat one instruction fix for
	208	* continuations on the SPARC. It flushes the register windows so
	209	* that all the state of the process is contained in the stack.
	210	*/
	211
	212	#ifdef sparc
	213	# define SCM_FLUSH_REGISTER_WINDOWS asm("ta 3")
	214	#else
	215	# define SCM_FLUSH_REGISTER_WINDOWS /* empty */
	216	#endif
	217
	218	/* If stack is not longword aligned then
	219	*/
	220
	221	/* #define SHORT_ALIGN */
	222	#ifdef THINK_C
	223	# define SHORT_ALIGN
	224	#endif
	225	#ifdef MSDOS
	226	# define SHORT_ALIGN
	227	#endif
	228	#ifdef atarist
	229	# define SHORT_ALIGN
	230	#endif
	231
	232	#ifdef SHORT_ALIGN
	233	typedef short SCM_STACKITEM;
	234	#else
	235	typedef long SCM_STACKITEM;
	236	#endif
	237	\f
	238
82339094	239	#ifndef USE_THREADS
25d3ee9d MD	240	#define SCM_THREAD_DEFER
	241	#define SCM_THREAD_ALLOW
	242	#define SCM_THREAD_REDEFER
	243	#define SCM_THREAD_REALLOW_1
	244	#define SCM_THREAD_REALLOW_2
	245	#define SCM_THREAD_SWITCHING_CODE
82339094 MD	246	#endif
82339094 MD	247
0f2d19dd	248	extern unsigned int scm_async_clock;
82339094	249
25d3ee9d	250	#define SCM_ASYNC_TICK \
bfc69694	251	do { \
25d3ee9d MD	252	if (0 == --scm_async_clock) \
25d3ee9d MD	253	scm_async_click (); \
bfc69694	254	} while(0)
25d3ee9d	255
0f2d19dd JB	256	#ifdef SCM_CAREFUL_INTS
	257	#define SCM_CHECK_NOT_DISABLED \
	258	if (scm_ints_disabled) \
	259	fputs("ints already disabled\n", stderr); \
	260
	261	#define SCM_CHECK_NOT_ENABLED \
	262	if (!scm_ints_disabled) \
	263	fputs("ints already enabled\n", stderr); \
	264
	265	#else
	266	#define SCM_CHECK_NOT_DISABLED
	267	#define SCM_CHECK_NOT_ENABLED
	268	#endif
	269
	270
8417b665 JB	271	/* Anthony Green writes:
	272	When the compiler sees...
	273	DEFER_INTS;
	274	[critical code here]
	275	ALLOW_INTS;
	276	...it doesn't actually promise to keep the critical code within the
	277	boundries of the DEFER/ALLOW_INTS instructions. It may very well
	278	schedule it outside of the magic defined in those macros.
	279
	280	However, GCC's volatile asm feature forms a barrier over which code is
	281	never moved. So if you add...
35eec738 JB	282	asm ("");
	283	...to each of the DEFER_INTS and ALLOW_INTS macros, the critical
	284	code will always remain in place. asm's without inputs or outputs
	285	are implicitly volatile. */
8417b665	286	#ifdef __GNUC__
35eec738	287	#define SCM_FENCE asm /* volatile */ ("")
8417b665 JB	288	#else
	289	#define SCM_FENCE
	290	#endif
	291
0f2d19dd	292	#define SCM_DEFER_INTS \
bfc69694	293	do { \
8417b665	294	SCM_FENCE; \
0f2d19dd	295	SCM_CHECK_NOT_DISABLED; \
25d3ee9d	296	SCM_THREAD_DEFER; \
8417b665	297	SCM_FENCE; \
0f2d19dd	298	scm_ints_disabled = 1; \
8417b665	299	SCM_FENCE; \
bfc69694	300	} while (0)
0f2d19dd JB	301
	302
	303	#define SCM_ALLOW_INTS_ONLY \
bfc69694	304	do { \
25d3ee9d	305	SCM_THREAD_ALLOW; \
0f2d19dd	306	scm_ints_disabled = 0; \
bfc69694	307	} while (0)
0f2d19dd JB	308
	309
	310	#define SCM_ALLOW_INTS \
bfc69694	311	do { \
8417b665	312	SCM_FENCE; \
0f2d19dd	313	SCM_CHECK_NOT_ENABLED; \
c72cc5fb MD	314	SCM_THREAD_SWITCHING_CODE; \
c72cc5fb MD	315	SCM_FENCE; \
0f2d19dd	316	scm_ints_disabled = 0; \
8417b665 JB	317	SCM_FENCE; \
8417b665 JB	318	SCM_THREAD_ALLOW; \
0f2d19dd	319	SCM_ASYNC_TICK; \
8417b665	320	SCM_FENCE; \
bfc69694	321	} while (0)
0f2d19dd JB	322
	323
	324	#define SCM_REDEFER_INTS \
bfc69694	325	do { \
c72cc5fb	326	SCM_FENCE; \
25d3ee9d	327	SCM_THREAD_REDEFER; \
0f2d19dd	328	++scm_ints_disabled; \
c72cc5fb	329	SCM_FENCE; \
bfc69694	330	} while (0)
0f2d19dd JB	331
	332
	333	#define SCM_REALLOW_INTS \
bfc69694	334	do { \
c72cc5fb	335	SCM_FENCE; \
25d3ee9d	336	SCM_THREAD_REALLOW_1; \
c72cc5fb MD	337	SCM_THREAD_SWITCHING_CODE; \
c72cc5fb MD	338	SCM_FENCE; \
0f2d19dd JB	339	--scm_ints_disabled; \
0f2d19dd JB	340	if (!scm_ints_disabled) \
25d3ee9d MD	341	{ \
	342	SCM_THREAD_REALLOW_2; \
	343	SCM_ASYNC_TICK; \
	344	} \
c72cc5fb	345	SCM_FENCE; \
bfc69694	346	} while (0)
0f2d19dd JB	347
0f2d19dd JB	348
c72cc5fb	349	#define SCM_TICK \
bfc69694	350	do { \
c72cc5fb MD	351	SCM_DEFER_INTS; \
c72cc5fb MD	352	SCM_ALLOW_INTS; \
bfc69694	353	} while (0)
0f2d19dd JB	354
	355	\f
	356
f83e2737 MD	357	/* Classification of critical sections
	358	*
	359	* When Guile moves to POSIX threads, it won't be possible to prevent
	360	* context switching. In fact, the whole idea of context switching is
	361	* bogus if threads are run by different processors. Therefore, we
	362	* must ultimately eliminate all critical sections or enforce them by
	363	* use of mutecis.
	364	*
	365	* All instances of SCM_DEFER_INTS and SCM_ALLOW_INTS should therefore
	366	* be classified and replaced by one of the delimiters below. If you
	367	* understand what this is all about, I'd like to encourage you to
	368	* help with this task. The set of classes below must of course be
	369	* incrementally augmented.
	370	*
	371	* MDJ 980419 <djurfeldt@nada.kth.se>
	372	*/
	373
	374	/* A sections
	375	*
	376	* Allocation of a cell with type tag in the CAR.
	377	*
	378	* With POSIX threads, each thread will have a private pool of free
	379	* cells. Therefore, this type of section can be removed. But! It
	380	* is important that the CDR is initialized first (with the CAR still
	381	* indicating a free cell) so that we can guarantee a consistent heap
	382	* at all times.
	383	*/
	384
	385	#ifdef SCM_POSIX_THREADS
	386	#define SCM_ENTER_A_SECTION
	387	#define SCM_EXIT_A_SECTION
	388	#else
	389	#define SCM_ENTER_A_SECTION SCM_DEFER_INTS
	390	#define SCM_EXIT_A_SECTION SCM_ALLOW_INTS
	391	#endif
	392
	393	\f
	394
0f2d19dd JB	395	/** SCM_ASSERT
	396	**
	397	**/
	398
	399
	400	#ifdef SCM_RECKLESS
	401	#define SCM_ASSERT(_cond, _arg, _pos, _subr)
	402	#define SCM_ASRTGO(_cond, _label)
	403	#else
	404	#define SCM_ASSERT(_cond, _arg, _pos, _subr) \
	405	if (!(_cond)) \
	406	scm_wta(_arg, (char *)(_pos), _subr)
	407	#define SCM_ASRTGO(_cond, _label) \
	408	if (!(_cond)) \
	409	goto _label
	410	#endif
95b88819	411
9de33deb MD	412	/*
	413	* SCM_WTA_DISPATCH
	414	*/
	415
b3c8a0f5 MD	416	extern SCM scm_call_generic_0 (SCM gf);
	417
	418	#define SCM_WTA_DISPATCH_0(gf, arg, pos, subr) \
	419	return ((gf) \
	420	? scm_call_generic_0 ((gf)) \
	421	: scm_wta ((arg), (char *) (pos), (subr)))
	422	#define SCM_GASSERT0(cond, gf, arg, pos, subr) \
ff725a17	423	if (!(cond)) SCM_WTA_DISPATCH_0((gf), (arg), (pos), (subr))
b3c8a0f5	424
9de33deb MD	425	extern SCM scm_call_generic_1 (SCM gf, SCM a1);
	426
	427	#define SCM_WTA_DISPATCH_1(gf, a1, pos, subr) \
	428	return ((gf) \
	429	? scm_call_generic_1 ((gf), (a1)) \
	430	: scm_wta ((a1), (char *) (pos), (subr)))
	431	#define SCM_GASSERT1(cond, gf, a1, pos, subr) \
	432	if (!(cond)) SCM_WTA_DISPATCH_1((gf), (a1), (pos), (subr))
	433
	434	extern SCM scm_call_generic_2 (SCM gf, SCM a1, SCM a2);
	435
	436	#define SCM_WTA_DISPATCH_2(gf, a1, a2, pos, subr) \
	437	return ((gf) \
	438	? scm_call_generic_2 ((gf), (a1), (a2)) \
	439	: scm_wta ((pos) == SCM_ARG1 ? (a1) : (a2), (char *) (pos), (subr)))
	440	#define SCM_GASSERT2(cond, gf, a1, a2, pos, subr) \
	441	if (!(cond)) SCM_WTA_DISPATCH_2((gf), (a1), (a2), (pos), (subr))
	442
89c358b1 MD	443	extern SCM scm_apply_generic (SCM gf, SCM args);
	444
	445	#define SCM_WTA_DISPATCH_n(gf, args, pos, subr) \
	446	return ((gf) \
	447	? scm_apply_generic ((gf), (args)) \
	448	: scm_wta (scm_list_ref ((args), SCM_MAKINUM ((pos) - 1)), \
	449	(char *) (pos), \
	450	(subr)))
	451	#define SCM_GASSERTn(cond, gf, args, pos, subr) \
	452	if (!(cond)) SCM_WTA_DISPATCH_n((gf), (args), (pos), (subr))
	453
c751e5e3 GB	454	#ifndef SCM_MAGIC_SNARFER
	455	/* Let these macros pass through if
	456	we are snarfing; thus we can tell the
	457	difference between the use of an actual
	458	number vs. the use of one of these macros --
f5421cfc	459	actual numbers in SCM_VALIDATE_* and SCM_ASSERT
c751e5e3 GB	460	constructs must match the formal argument name,
	461	but using SCM_ARG* avoids the test */
	462
0f2d19dd JB	463	#define SCM_ARGn 0
	464	#define SCM_ARG1 1
	465	#define SCM_ARG2 2
	466	#define SCM_ARG3 3
	467	#define SCM_ARG4 4
	468	#define SCM_ARG5 5
1146b6cd GH	469	#define SCM_ARG6 6
1146b6cd GH	470	#define SCM_ARG7 7
f5bf2977	471	/* #define SCM_ARGERR(X) ((X) < SCM_WNA \
0f2d19dd JB	472	? (char *)(X) \
0f2d19dd JB	473	: "wrong type argument")
f5bf2977	474	*/
0f2d19dd JB	475
	476	/* Following must match entry indexes in scm_errmsgs[].
	477	* Also, SCM_WNA must follow the last SCM_ARGn in sequence.
	478	*/
	479	#define SCM_WNA 8
e1724d20	480	/* #define SCM_OVSCM_FLOW 9 */
0f2d19dd JB	481	#define SCM_OUTOFRANGE 10
0f2d19dd JB	482	#define SCM_NALLOC 11
f5bf2977 GH	483	/* #define SCM_STACK_OVFLOW 12 */
f5bf2977 GH	484	/* #define SCM_EXIT 13 */
0f2d19dd	485
c751e5e3	486	#endif /* SCM_MAGIC_SNARFER */
0f2d19dd JB	487
	488	/* (...still matching scm_errmsgs) These
	489	* are signals. Signals may become errors
	490	* but are distinguished because they first
	491	* try to invoke a handler that can resume
	492	* the interrupted routine.
	493	*/
	494	#define SCM_HUP_SIGNAL 14
	495	#define SCM_INT_SIGNAL 15
	496	#define SCM_FPE_SIGNAL 16
	497	#define SCM_BUS_SIGNAL 17
	498	#define SCM_SEGV_SIGNAL 18
	499	#define SCM_ALRM_SIGNAL 19
	500	#define SCM_GC_SIGNAL 20
	501	#define SCM_TICK_SIGNAL 21
	502
	503	#define SCM_SIG_ORD(X) ((X) - SCM_HUP_SIGNAL)
	504	#define SCM_ORD_SIG(X) ((X) + SCM_HUP_SIGNAL)
	505	#define SCM_NUM_SIGS (SCM_SIG_ORD (SCM_TICK_SIGNAL) + 1)
	506
82339094	507	#if 0
0f2d19dd JB	508	struct errdesc
	509	{
	510	char *msg;
	511	char *s_response;
	512	short parent_err;
	513	};
	514
	515
	516	extern struct errdesc scm_errmsgs[];
82339094	517	#endif
0f2d19dd JB	518
	519	\f
	520
	521	/* SCM_EXIT_SUCCESS is the default code to return from SCM if no errors
	522	* were encountered. SCM_EXIT_FAILURE is the default code to return from
	523	* SCM if errors were encountered. The return code can be explicitly
	524	* specified in a SCM program with (scm_quit <n>).
	525	*/
	526
	527	#ifndef SCM_EXIT_SUCCESS
	528	#ifdef vms
	529	#define SCM_EXIT_SUCCESS 1
	530	#else
	531	#define SCM_EXIT_SUCCESS 0
	532	#endif /* def vms */
	533	#endif /* ndef SCM_EXIT_SUCCESS */
	534	#ifndef SCM_EXIT_FAILURE
	535	#ifdef vms
	536	#define SCM_EXIT_FAILURE 2
	537	#else
	538	#define SCM_EXIT_FAILURE 1
	539	#endif /* def vms */
	540	#endif /* ndef SCM_EXIT_FAILURE */
	541
	542
	543
	544	\f
0f2d19dd JB	545
0f2d19dd JB	546	#endif /* __SCMH */