6 /* Copyright (C) 1995,1996,1998,1999,2000,2001,2002,2003, 2006, 2007, 2008, 2010 Free Software Foundation, Inc.
8 * This library is free software; you can redistribute it and/or
9 * modify it under the terms of the GNU Lesser General Public
10 * License as published by the Free Software Foundation; either
11 * version 2.1 of the License, or (at your option) any later version.
13 * This library is distributed in the hope that it will be useful,
14 * but WITHOUT ANY WARRANTY; without even the implied warranty of
15 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
16 * Lesser General Public License for more details.
18 * You should have received a copy of the GNU Lesser General Public
19 * License along with this library; if not, write to the Free Software
20 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
25 /**********************************************************************
26 This file is Guile's central public header.
28 When included by other files, this file should preceed any include
31 Under *NO* circumstances should new items be added to the global
32 namespace (via adding #define, typedef, or similar to this file) with
33 generic names. This usually means that any new names should be
34 prefixed by either SCM_ or GUILE_. i.e. do *not* #define HAVE_FOO or
35 SIZEOF_BAR. See configure.in, gen-scmconfig.h.in, and
36 gen-scmconfig.c for examples of how to properly handle this issue.
37 The main documentation is in gen-scmconfig.c.
39 "What's the difference between _scm.h and __scm.h?"
41 _scm.h is not installed; it's only visible to the libguile sources
42 themselves, and it includes config.h, the private config header.
44 __scm.h is installed, and is #included by <libguile.h>. If both
45 the client and libguile need some piece of information, and it
46 doesn't fit well into the header file for any particular module, it
47 should go in __scm.h. __scm.h includes scmconfig.h, the public
49 **********************************************************************/
51 /* What did the configure script discover about the outside world? */
52 #include "libguile/scmconfig.h"
58 * The following macros are used to provide additional information for the
59 * compiler, which may help to do better error checking and code
60 * optimization. A second benefit of these macros is, that they also provide
61 * additional information to the developers.
64 /* The macro SCM_NORETURN indicates that a function will never return.
66 * 1) int foo (char arg) SCM_NORETURN;
69 #define SCM_NORETURN __attribute__ ((noreturn))
74 /* The macro SCM_UNUSED indicates that a function, function argument or
75 * variable may potentially be unused.
77 * 1) static int unused_function (char arg) SCM_UNUSED;
78 * 2) int foo (char unused_argument SCM_UNUSED);
79 * 3) int unused_variable SCM_UNUSED;
82 #define SCM_UNUSED __attribute__ ((unused))
88 /* The SCM_EXPECT macros provide branch prediction hints to the compiler. To
89 * use only in places where the result of the expression under "normal"
90 * circumstances is known. */
91 #if defined(__GNUC__) && (__GNUC__ >= 3)
92 # define SCM_EXPECT __builtin_expect
94 # define SCM_EXPECT(_expr, _value) (_expr)
97 #define SCM_LIKELY(_expr) SCM_EXPECT ((_expr), 1)
98 #define SCM_UNLIKELY(_expr) SCM_EXPECT ((_expr), 0)
102 /* {Supported Options}
104 * These may be defined or undefined.
107 /* #define GUILE_DEBUG_FREELIST */
109 /* All the number support there is.
113 /* GC should relinquish empty cons-pair arenas. */
114 /* cmm:FIXME look at this after done mangling the GC */
115 /* #define GC_FREE_SEGMENTS */
117 /* Provide a scheme-accessible count-down timer that
118 * generates a pseudo-interrupt.
123 /* Use engineering notation when converting numbers strings?
128 /* {Unsupported Options}
130 * These must be defined as given here.
136 /* Guile Scheme supports the #f/() distinction; Guile Lisp won't. We
137 have horrible plans for their unification. */
142 /* Random options (not yet supported or in final form). */
144 #define STACK_CHECKING
145 #undef NO_CEVAL_STACK_CHECKING
149 /* SCM_API is a macro prepended to all function and data definitions
150 which should be exported or imported in the resulting dynamic link
151 library (DLL) in the Win32 port. */
153 #if defined (SCM_IMPORT)
154 # define SCM_API __declspec (dllimport) extern
155 #elif defined (SCM_EXPORT) || defined (DLL_EXPORT)
156 # define SCM_API __declspec (dllexport) extern
158 # define SCM_API extern
163 /* {Debugging Options}
165 * These compile time options determine whether to include code that is only
166 * useful for debugging guile itself or C level extensions to guile. The
167 * common prefix for all option macros of this kind is "SCM_DEBUG_". It is
168 * guaranteed that a macro named SCM_DEBUG_XXX is always defined (typically to
169 * either 0 or 1), i. e. there is no need to test for the undefined case.
170 * This allows to use these definitions comfortably within code, as in the
172 * #define FOO do { if (SCM_DEBUG_XXX) bar(); else baz(); } while (0)
173 * Any sane compiler will remove the unused branch without any performance
174 * penalty for the resulting code.
176 * Note: Some SCM_DEBUG_XXX options are not settable at configure time.
177 * To change the value of such options you will have to edit this header
178 * file or give suitable options to make, like:
179 * make all CFLAGS="-DSCM_DEBUG_XXX=1 ..."
183 /* The value of SCM_DEBUG determines the default for most of the not yet
184 * defined debugging options. This allows, for example, to enable most of the
185 * debugging options by simply defining SCM_DEBUG as 1.
191 /* If SCM_DEBUG_CELL_ACCESSES is set to 1, cell accesses will perform
192 * exhaustive parameter checking: It will be verified that cell parameters
193 * actually point to a valid heap cell. Note: If this option is enabled,
194 * guile will run about ten times slower than normally.
196 #ifndef SCM_DEBUG_CELL_ACCESSES
197 #define SCM_DEBUG_CELL_ACCESSES SCM_DEBUG
200 /* If SCM_DEBUG_INTERRUPTS is set to 1, with every deferring and allowing of
201 * interrupts a consistency check will be performed.
203 #ifndef SCM_DEBUG_INTERRUPTS
204 #define SCM_DEBUG_INTERRUPTS SCM_DEBUG
207 /* If SCM_DEBUG_PAIR_ACCESSES is set to 1, accesses to cons cells will be
208 * exhaustively checked. Note: If this option is enabled, guile will run
209 * slower than normally.
211 #ifndef SCM_DEBUG_PAIR_ACCESSES
212 #define SCM_DEBUG_PAIR_ACCESSES SCM_DEBUG
215 /* If SCM_DEBUG_REST_ARGUMENT is set to 1, functions that take rest arguments
216 * will check whether the rest arguments are actually passed as a proper list.
217 * Otherwise, if SCM_DEBUG_REST_ARGUMENT is 0, functions that take rest
218 * arguments will take it for granted that these are passed as a proper list.
220 #ifndef SCM_DEBUG_REST_ARGUMENT
221 #define SCM_DEBUG_REST_ARGUMENT SCM_DEBUG
224 /* The macro SCM_DEBUG_TYPING_STRICTNESS indicates what level of type checking
225 * shall be performed with respect to the use of the SCM datatype. The macro
226 * may be defined to one of the values 0, 1 and 2.
228 * A value of 0 means that there will be no compile time type checking, since
229 * the SCM datatype will be declared as an integral type. This setting should
230 * only be used on systems, where casting from integral types to pointers may
231 * lead to loss of bit information.
233 * A value of 1 means that there will an intermediate level of compile time
234 * type checking, since the SCM datatype will be declared as a pointer to an
235 * undefined struct. This setting is the default, since it does not cost
236 * anything in terms of performance or code size.
238 * A value of 2 provides a maximum level of compile time type checking since
239 * the SCM datatype will be declared as a struct. This setting should be used
240 * for _compile time_ type checking only, since the compiled result is likely
241 * to be quite inefficient. The right way to make use of this option is to do
242 * a 'make clean; make CFLAGS=-DSCM_DEBUG_TYPING_STRICTNESS=2', fix your
243 * errors, and then do 'make clean; make'.
245 #ifndef SCM_DEBUG_TYPING_STRICTNESS
246 #define SCM_DEBUG_TYPING_STRICTNESS 1
249 /* If SCM_DEBUG_DEBUGGING_SUPPORT is set to 1, guile will provide a set of
250 * special functions that support debugging with a debugger like gdb or
251 * debugging of guile internals on the scheme level. The behaviour of guile
252 * is not changed by this macro, only the set of functions that are available
253 * will differ. All functions that are introduced this way have the prefix
254 * 'scm_dbg_' on the C level and the prefix 'dbg-' on the scheme level. This
255 * allows to easily determine the set of support functions, given that your
256 * debugger or repl provide automatic name completion. Note that these
257 * functions are intended to be used during interactive debugging sessions
258 * only. They are not considered part of guile's official API. They may
259 * change or disappear without notice or deprecation phase.
261 #ifndef SCM_DEBUG_DEBUGGING_SUPPORT
262 #define SCM_DEBUG_DEBUGGING_SUPPORT SCM_DEBUG
269 * These compile time options determine whether code for certain features
270 * should be compiled into guile. The common prefix for all option macros
271 * of this kind is "SCM_ENABLE_". It is guaranteed that a macro named
272 * SCM_ENABLE_XXX is defined to be either 0 or 1, i. e. there is no need to
273 * test for the undefined case. This allows to use these definitions
274 * comfortably within code, as in the following example:
275 * #define FOO do { if (SCM_ENABLE_XXX) bar(); else baz(); } while (0)
276 * Any sane compiler will remove the unused branch without any performance
277 * penalty for the resulting code.
279 * Note: Some SCM_ENABLE_XXX options are not settable at configure time.
280 * To change the value of such options you will have to edit this header
281 * file or give suitable options to make, like:
282 * make all CFLAGS="-DSCM_ENABLE_XXX=1 ..."
285 /* If SCM_ENABLE_DEPRECATED is set to 1, deprecated code will be included in
286 * guile, as well as some functions to issue run-time warnings about uses of
287 * deprecated functions.
289 #ifndef SCM_ENABLE_DEPRECATED
290 #define SCM_ENABLE_DEPRECATED 0
295 /* {Architecture and compiler properties}
297 * Guile as of today can only work on systems which fulfill at least the
298 * following requirements:
300 * - scm_t_bits and SCM variables have at least 32 bits.
301 * Guile's type system is based on this assumption.
303 * - sizeof (scm_t_bits) >= sizeof (void*) and sizeof (SCM) >= sizeof (void*)
304 * Guile's type system is based on this assumption, since it must be
305 * possible to store pointers to cells on the heap in scm_t_bits and SCM
308 * - sizeof (scm_t_bits) >= 4 and sizeof (scm_t_bits) is a power of 2.
309 * Guile's type system is based on this assumption. In particular, it is
310 * assumed that cells, i. e. pairs of scm_t_bits variables, are eight
311 * character aligned. This is because three bits of a scm_t_bits variable
312 * that is holding a pointer to a cell on the heap must be available for
315 * - sizeof (scm_t_bits) <= sizeof (void*) and sizeof (SCM) <= sizeof (void*)
316 * In some parts of guile, scm_t_bits and SCM variables are passed to
317 * functions as void* arguments. Together with the requirement above, this
318 * requires a one-to-one correspondence between the size of a void* and the
319 * sizes of scm_t_bits and SCM variables.
321 * - numbers are encoded using two's complement.
322 * The implementation of the bitwise scheme level operations is based on
329 # define SCM_CHAR_BIT CHAR_BIT
331 # define SCM_CHAR_BIT 8
335 # define SCM_LONG_BIT LONG_BIT
337 # define SCM_LONG_BIT (SCM_CHAR_BIT * sizeof (long) / sizeof (char))
341 # define SCM_CHAR_CODE_LIMIT (UCHAR_MAX + 1L)
343 # define SCM_CHAR_CODE_LIMIT 256L
346 #define SCM_I_UTYPE_MAX(type) ((type)-1)
347 #define SCM_I_TYPE_MAX(type,umax) ((type)((umax)/2))
348 #define SCM_I_TYPE_MIN(type,umax) (-((type)((umax)/2))-1)
350 #define SCM_T_UINT8_MAX SCM_I_UTYPE_MAX(scm_t_uint8)
351 #define SCM_T_INT8_MIN SCM_I_TYPE_MIN(scm_t_int8,SCM_T_UINT8_MAX)
352 #define SCM_T_INT8_MAX SCM_I_TYPE_MAX(scm_t_int8,SCM_T_UINT8_MAX)
354 #define SCM_T_UINT16_MAX SCM_I_UTYPE_MAX(scm_t_uint16)
355 #define SCM_T_INT16_MIN SCM_I_TYPE_MIN(scm_t_int16,SCM_T_UINT16_MAX)
356 #define SCM_T_INT16_MAX SCM_I_TYPE_MAX(scm_t_int16,SCM_T_UINT16_MAX)
358 #define SCM_T_UINT32_MAX SCM_I_UTYPE_MAX(scm_t_uint32)
359 #define SCM_T_INT32_MIN SCM_I_TYPE_MIN(scm_t_int32,SCM_T_UINT32_MAX)
360 #define SCM_T_INT32_MAX SCM_I_TYPE_MAX(scm_t_int32,SCM_T_UINT32_MAX)
362 #define SCM_T_UINT64_MAX SCM_I_UTYPE_MAX(scm_t_uint64)
363 #define SCM_T_INT64_MIN SCM_I_TYPE_MIN(scm_t_int64,SCM_T_UINT64_MAX)
364 #define SCM_T_INT64_MAX SCM_I_TYPE_MAX(scm_t_int64,SCM_T_UINT64_MAX)
366 #if SCM_SIZEOF_LONG_LONG
367 #define SCM_I_ULLONG_MAX SCM_I_UTYPE_MAX(unsigned long long)
368 #define SCM_I_LLONG_MIN SCM_I_TYPE_MIN(long long,SCM_I_ULLONG_MAX)
369 #define SCM_I_LLONG_MAX SCM_I_TYPE_MAX(long long,SCM_I_ULLONG_MAX)
372 #define SCM_T_UINTMAX_MAX SCM_I_UTYPE_MAX(scm_t_uintmax)
373 #define SCM_T_INTMAX_MIN SCM_I_TYPE_MIN(scm_t_intmax,SCM_T_UINTMAX_MAX)
374 #define SCM_T_INTMAX_MAX SCM_I_TYPE_MAX(scm_t_intmax,SCM_T_UINTMAX_MAX)
376 #define SCM_I_SIZE_MAX SCM_I_UTYPE_MAX(size_t)
377 #define SCM_I_SSIZE_MIN SCM_I_TYPE_MIN(ssize_t,SCM_I_SIZE_MAX)
378 #define SCM_I_SSIZE_MAX SCM_I_TYPE_MAX(ssize_t,SCM_I_SIZE_MAX)
382 #include "libguile/tags.h"
386 # ifndef CHEAP_CONTINUATIONS
387 typedef int jmp_buf[17];
388 extern int setjump(jmp_buf env);
389 extern int longjump(jmp_buf env, int ret);
390 # define setjmp setjump
391 # define longjmp longjump
397 typedef int jmp_buf[112];
398 extern int setjump(jmp_buf env);
399 extern int longjump(jmp_buf env, int ret);
400 # define setjmp setjump
401 # define longjmp longjump
402 # else /* ndef _CRAY1 */
403 # if defined (__ia64__)
404 /* For IA64, emulate the setjmp API using getcontext. */
406 # include <ucontext.h>
411 # define SCM_I_SETJMP(JB) \
413 getcontext (&((JB).ctx)), \
414 ((JB).fresh ? ((JB).fresh = 0, 0) : 1) )
415 # define SCM_I_LONGJMP(JB,VAL) scm_ia64_longjmp (&(JB), VAL)
416 void scm_ia64_longjmp (scm_i_jmp_buf *, int);
417 # else /* ndef __ia64__ */
419 # endif /* ndef __ia64__ */
420 # endif /* ndef _CRAY1 */
421 #endif /* ndef vms */
423 /* For any platform where SCM_I_SETJMP hasn't been defined in some
424 special way above, map SCM_I_SETJMP, SCM_I_LONGJMP and
425 scm_i_jmp_buf to setjmp, longjmp and jmp_buf. */
427 #define scm_i_jmp_buf jmp_buf
428 #define SCM_I_SETJMP setjmp
429 #define SCM_I_LONGJMP longjmp
432 /* James Clark came up with this neat one instruction fix for
433 * continuations on the SPARC. It flushes the register windows so
434 * that all the state of the process is contained in the stack.
437 #if defined (sparc) || defined (__sparc__) || defined (__sparc)
438 # define SCM_FLUSH_REGISTER_WINDOWS asm("ta 3")
440 # define SCM_FLUSH_REGISTER_WINDOWS /* empty */
443 /* If stack is not longword aligned then
446 /* #define SHORT_ALIGN */
458 typedef short SCM_STACKITEM;
460 typedef long SCM_STACKITEM;
463 /* Cast pointer through (void *) in order to avoid compiler warnings
464 when strict aliasing is enabled */
465 #define SCM_STACK_PTR(ptr) ((SCM_STACKITEM *) (void *) (ptr))
468 #define SCM_ASYNC_TICK /*fixme* should change names */ \
470 if (SCM_I_CURRENT_THREAD->pending_asyncs) \
471 scm_async_click (); \
475 /* Anthony Green writes:
476 When the compiler sees...
480 ...it doesn't actually promise to keep the critical code within the
481 boundries of the DEFER/ALLOW_INTS instructions. It may very well
482 schedule it outside of the magic defined in those macros.
484 However, GCC's volatile asm feature forms a barrier over which code is
485 never moved. So if you add...
487 ...to each of the DEFER_INTS and ALLOW_INTS macros, the critical
488 code will always remain in place. asm's without inputs or outputs
489 are implicitly volatile. */
491 #define SCM_FENCE asm /* volatile */ ("")
492 #elif defined (__INTEL_COMPILER) && defined (__ia64)
493 #define SCM_FENCE __memory_barrier()
501 SCM_THREAD_SWITCHING_CODE; \
512 #define SCM_ASSERT(_cond, _arg, _pos, _subr)
513 #define SCM_ASSERT_TYPE(_cond, _arg, _pos, _subr, _msg)
514 #define SCM_ASRTGO(_cond, _label)
516 #define SCM_ASSERT(_cond, _arg, _pos, _subr) \
517 do { if (SCM_UNLIKELY (!(_cond))) \
518 scm_wrong_type_arg (_subr, _pos, _arg); } while (0)
519 #define SCM_ASSERT_TYPE(_cond, _arg, _pos, _subr, _msg) \
520 do { if (SCM_UNLIKELY (!(_cond))) \
521 scm_wrong_type_arg_msg(_subr, _pos, _arg, _msg); } while (0)
522 #define SCM_ASRTGO(_cond, _label) \
523 do { if (SCM_UNLIKELY (!(_cond))) \
524 goto _label; } while (0)
531 /* Dirk:FIXME:: In all of the SCM_WTA_DISPATCH_* macros it is assumed that
532 * 'gf' is zero if uninitialized. It would be cleaner if some valid SCM value
533 * like SCM_BOOL_F or SCM_UNDEFINED was chosen.
536 SCM_API SCM scm_call_generic_0 (SCM gf);
538 #define SCM_WTA_DISPATCH_0(gf, subr) \
539 return (SCM_UNPACK (gf) \
540 ? scm_call_generic_0 ((gf)) \
541 : (scm_error_num_args_subr ((subr)), SCM_UNSPECIFIED))
542 #define SCM_GASSERT0(cond, gf, subr) \
543 if (SCM_UNLIKELY(!(cond))) \
544 SCM_WTA_DISPATCH_0((gf), (subr))
546 SCM_API SCM scm_call_generic_1 (SCM gf, SCM a1);
548 #define SCM_WTA_DISPATCH_1(gf, a1, pos, subr) \
549 return (SCM_UNPACK (gf) \
550 ? scm_call_generic_1 ((gf), (a1)) \
551 : (scm_wrong_type_arg ((subr), (pos), (a1)), SCM_UNSPECIFIED))
552 #define SCM_GASSERT1(cond, gf, a1, pos, subr) \
553 if (SCM_UNLIKELY (!(cond))) \
554 SCM_WTA_DISPATCH_1((gf), (a1), (pos), (subr))
556 SCM_API SCM scm_call_generic_2 (SCM gf, SCM a1, SCM a2);
558 #define SCM_WTA_DISPATCH_2(gf, a1, a2, pos, subr) \
559 return (SCM_UNPACK (gf) \
560 ? scm_call_generic_2 ((gf), (a1), (a2)) \
561 : (scm_wrong_type_arg ((subr), (pos), \
562 (pos) == SCM_ARG1 ? (a1) : (a2)), \
564 #define SCM_GASSERT2(cond, gf, a1, a2, pos, subr) \
565 if (SCM_UNLIKELY (!(cond))) \
566 SCM_WTA_DISPATCH_2((gf), (a1), (a2), (pos), (subr))
568 SCM_API SCM scm_apply_generic (SCM gf, SCM args);
570 #define SCM_WTA_DISPATCH_n(gf, args, pos, subr) \
571 return (SCM_UNPACK (gf) \
572 ? scm_apply_generic ((gf), (args)) \
573 : (scm_wrong_type_arg ((subr), (pos), \
574 scm_list_ref ((args), \
575 scm_from_int ((pos) - 1))), \
577 #define SCM_GASSERTn(cond, gf, args, pos, subr) \
578 if (SCM_UNLIKELY (!(cond))) \
579 SCM_WTA_DISPATCH_n((gf), (args), (pos), (subr))
581 #ifndef SCM_MAGIC_SNARFER
582 /* Let these macros pass through if
583 we are snarfing; thus we can tell the
584 difference between the use of an actual
585 number vs. the use of one of these macros --
586 actual numbers in SCM_VALIDATE_* and SCM_ASSERT
587 constructs must match the formal argument name,
588 but using SCM_ARG* avoids the test */
599 #endif /* SCM_MAGIC_SNARFER */
603 /* SCM_EXIT_SUCCESS is the default code to return from SCM if no errors
604 * were encountered. SCM_EXIT_FAILURE is the default code to return from
605 * SCM if errors were encountered. The return code can be explicitly
606 * specified in a SCM program with (scm_quit <n>).
609 #ifndef SCM_EXIT_SUCCESS
611 #define SCM_EXIT_SUCCESS 1
613 #define SCM_EXIT_SUCCESS 0
615 #endif /* ndef SCM_EXIT_SUCCESS */
616 #ifndef SCM_EXIT_FAILURE
618 #define SCM_EXIT_FAILURE 2
620 #define SCM_EXIT_FAILURE 1
622 #endif /* ndef SCM_EXIT_FAILURE */
624 /* Define SCM_C_INLINE_KEYWORD so that it can be used as a replacement
625 for the "inline" keyword, expanding to nothing when "inline" is not
630 #define SCM_C_INLINE_KEYWORD SCM_C_INLINE
632 #define SCM_C_INLINE_KEYWORD
635 #endif /* SCM___SCM_H */