libguile/__scm.h

   1 /* classes: h_files */
   2
   3 #ifndef SCM___SCM_H
   4 #define SCM___SCM_H
   5
   6 /* Copyright (C) 1995,1996,1998,1999,2000,2001,2002,2003, 2006, 2007, 2008, 2009 Free Software Foundation, Inc.
   7  *
   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.
  12  *
  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.
  17  *
  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
  21  */
  22
  23 \f
  24
  25 /**********************************************************************
  26  This file is Guile's central public header.
  27
  28  When included by other files, this file should preceed any include
  29  other than __scm.h.
  30
  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.
  38
  39  "What's the difference between _scm.h and __scm.h?"
  40
  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.
  43
  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
  48    config header.
  49  **********************************************************************/
  50
  51 /* What did the configure script discover about the outside world?  */
  52 #include "libguile/scmconfig.h"
  53
  54 \f
  55
  56 /* {Compiler hints}
  57  *
  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.
  62  */
  63
  64 /* The macro SCM_NORETURN indicates that a function will never return.
  65  * Examples:
  66  *   1) int foo (char arg) SCM_NORETURN;
  67  */
  68 #ifdef __GNUC__
  69 #define SCM_NORETURN __attribute__ ((noreturn))
  70 #else
  71 #define SCM_NORETURN
  72 #endif
  73
  74 /* The macro SCM_UNUSED indicates that a function, function argument or
  75  * variable may potentially be unused.
  76  * Examples:
  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;
  80  */
  81 #ifdef __GNUC__
  82 #define SCM_UNUSED __attribute__ ((unused))
  83 #else
  84 #define SCM_UNUSED
  85 #endif
  86
  87
  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
  93 #else
  94 # define SCM_EXPECT(_expr, _value) (_expr)
  95 #endif
  96
  97 #define SCM_LIKELY(_expr)    SCM_EXPECT ((_expr), 1)
  98 #define SCM_UNLIKELY(_expr)  SCM_EXPECT ((_expr), 0)
  99
 100 /* The SCM_INTERNAL macro makes it possible to explicitly declare a function
 101  * as having "internal" linkage.  However our current tack on this problem is
 102  * to use GCC 4's -fvisibility=hidden, making functions internal by default,
 103  * and then SCM_API marks them for export. */
 104 #define SCM_INTERNAL  extern
 105
 106
 107 \f
 108 /* {Supported Options}
 109  *
 110  * These may be defined or undefined.
 111  */
 112
 113 /* #define GUILE_DEBUG_FREELIST */
 114
 115 /* All the number support there is.
 116  */
 117 #define BIGNUMS
 118
 119 /* GC should relinquish empty cons-pair arenas. */
 120 /* cmm:FIXME look at this after done mangling the GC */
 121 /* #define GC_FREE_SEGMENTS */
 122
 123 /* Provide a scheme-accessible count-down timer that
 124  * generates a pseudo-interrupt.
 125  */
 126 #define TICKS
 127
 128
 129 /* Use engineering notation when converting numbers strings?
 130  */
 131 #undef ENGNOT
 132
 133 \f
 134 /* {Unsupported Options}
 135  *
 136  * These must be defined as given here.
 137  */
 138
 139
 140 /* Guile Scheme supports the #f/() distinction; Guile Lisp won't.  We
 141    have horrible plans for their unification.  */
 142 #undef SICP
 143
 144 \f
 145
 146 /* Random options (not yet supported or in final form). */
 147
 148 #define STACK_CHECKING
 149 #undef NO_CEVAL_STACK_CHECKING
 150
 151 \f
 152
 153 /* SCM_API is a macro prepended to all function and data definitions
 154    which should be exported from libguile. */
 155
 156 #if BUILDING_LIBGUILE && HAVE_VISIBILITY
 157 # define SCM_API extern __attribute__((__visibility__("default")))
 158 #elif BUILDING_LIBGUILE && defined _MSC_VER
 159 # define SCM_API __declspec(dllexport) extern
 160 #elif defined _MSC_VER
 161 # define SCM_API __declspec(dllimport) extern
 162 #else
 163 # define SCM_API extern
 164 #endif
 165
 166 \f
 167
 168 /* {Debugging Options}
 169  *
 170  * These compile time options determine whether to include code that is only
 171  * useful for debugging guile itself or C level extensions to guile.  The
 172  * common prefix for all option macros of this kind is "SCM_DEBUG_".  It is
 173  * guaranteed that a macro named SCM_DEBUG_XXX is always defined (typically to
 174  * either 0 or 1), i. e. there is no need to test for the undefined case.
 175  * This allows to use these definitions comfortably within code, as in the
 176  * following example:
 177  *   #define FOO do { if (SCM_DEBUG_XXX) bar(); else baz(); } while (0)
 178  * Any sane compiler will remove the unused branch without any performance
 179  * penalty for the resulting code.
 180  *
 181  * Note:  Some SCM_DEBUG_XXX options are not settable at configure time.
 182  * To change the value of such options you will have to edit this header
 183  * file or give suitable options to make, like:
 184  *   make all CFLAGS="-DSCM_DEBUG_XXX=1 ..."
 185  */
 186
 187
 188 /* The value of SCM_DEBUG determines the default for most of the not yet
 189  * defined debugging options.  This allows, for example, to enable most of the
 190  * debugging options by simply defining SCM_DEBUG as 1.
 191  */
 192 #ifndef SCM_DEBUG
 193 #define SCM_DEBUG 0
 194 #endif
 195
 196 /* For debugging purposes: define this is to ensure nobody is using
 197  * the mark bits outside of the marking phase.  This is meant for
 198  * debugging purposes only.
 199  */
 200 #ifndef SCM_DEBUG_MARKING_API
 201 #define SCM_DEBUG_MARKING_API 0
 202 #endif
 203
 204 /* If SCM_DEBUG_CELL_ACCESSES is set to 1, cell accesses will perform
 205  * exhaustive parameter checking:  It will be verified that cell parameters
 206  * actually point to a valid heap cell.  Note:  If this option is enabled,
 207  * guile will run about ten times slower than normally.
 208  */
 209 #ifndef SCM_DEBUG_CELL_ACCESSES
 210 #define SCM_DEBUG_CELL_ACCESSES SCM_DEBUG
 211 #endif
 212
 213 /* If SCM_DEBUG_INTERRUPTS is set to 1, with every deferring and allowing of
 214  * interrupts a consistency check will be performed.
 215  */
 216 #ifndef SCM_DEBUG_INTERRUPTS
 217 #define SCM_DEBUG_INTERRUPTS SCM_DEBUG
 218 #endif
 219
 220 /* If SCM_DEBUG_PAIR_ACCESSES is set to 1, accesses to cons cells will be
 221  * exhaustively checked.  Note:  If this option is enabled, guile will run
 222  * slower than normally.
 223  */
 224 #ifndef SCM_DEBUG_PAIR_ACCESSES
 225 #define SCM_DEBUG_PAIR_ACCESSES SCM_DEBUG
 226 #endif
 227
 228 /* If SCM_DEBUG_REST_ARGUMENT is set to 1, functions that take rest arguments
 229  * will check whether the rest arguments are actually passed as a proper list.
 230  * Otherwise, if SCM_DEBUG_REST_ARGUMENT is 0, functions that take rest
 231  * arguments will take it for granted that these are passed as a proper list.
 232  */
 233 #ifndef SCM_DEBUG_REST_ARGUMENT
 234 #define SCM_DEBUG_REST_ARGUMENT SCM_DEBUG
 235 #endif
 236
 237 /* The macro SCM_DEBUG_TYPING_STRICTNESS indicates what level of type checking
 238  * shall be performed with respect to the use of the SCM datatype.  The macro
 239  * may be defined to one of the values 0, 1 and 2.
 240  *
 241  * A value of 0 means that there will be no compile time type checking, since
 242  * the SCM datatype will be declared as an integral type.  This setting should
 243  * only be used on systems, where casting from integral types to pointers may
 244  * lead to loss of bit information.
 245  *
 246  * A value of 1 means that there will an intermediate level of compile time
 247  * type checking, since the SCM datatype will be declared as a pointer to an
 248  * undefined struct.  This setting is the default, since it does not cost
 249  * anything in terms of performance or code size.
 250  *
 251  * A value of 2 provides a maximum level of compile time type checking since
 252  * the SCM datatype will be declared as a struct.  This setting should be used
 253  * for _compile time_ type checking only, since the compiled result is likely
 254  * to be quite inefficient.  The right way to make use of this option is to do
 255  * a 'make clean; make CFLAGS=-DSCM_DEBUG_TYPING_STRICTNESS=2', fix your
 256  * errors, and then do 'make clean; make'.
 257  */
 258 #ifndef SCM_DEBUG_TYPING_STRICTNESS
 259 #define SCM_DEBUG_TYPING_STRICTNESS 1
 260 #endif
 261
 262 /* If SCM_DEBUG_DEBUGGING_SUPPORT is set to 1, guile will provide a set of
 263  * special functions that support debugging with a debugger like gdb or
 264  * debugging of guile internals on the scheme level.  The behaviour of guile
 265  * is not changed by this macro, only the set of functions that are available
 266  * will differ.  All functions that are introduced this way have the prefix
 267  * 'scm_dbg_' on the C level and the prefix 'dbg-' on the scheme level.  This
 268  * allows to easily determine the set of support functions, given that your
 269  * debugger or repl provide automatic name completion.  Note that these
 270  * functions are intended to be used during interactive debugging sessions
 271  * only.  They are not considered part of guile's official API.  They may
 272  * change or disappear without notice or deprecation phase.
 273  */
 274 #ifndef SCM_DEBUG_DEBUGGING_SUPPORT
 275 #define SCM_DEBUG_DEBUGGING_SUPPORT SCM_DEBUG
 276 #endif
 277
 278 \f
 279
 280 /* {Feature Options}
 281  *
 282  * These compile time options determine whether code for certain features
 283  * should be compiled into guile.  The common prefix for all option macros
 284  * of this kind is "SCM_ENABLE_".  It is guaranteed that a macro named
 285  * SCM_ENABLE_XXX is defined to be either 0 or 1, i. e. there is no need to
 286  * test for the undefined case.  This allows to use these definitions
 287  * comfortably within code, as in the following example:
 288  *   #define FOO do { if (SCM_ENABLE_XXX) bar(); else baz(); } while (0)
 289  * Any sane compiler will remove the unused branch without any performance
 290  * penalty for the resulting code.
 291  *
 292  * Note:  Some SCM_ENABLE_XXX options are not settable at configure time.
 293  * To change the value of such options you will have to edit this header
 294  * file or give suitable options to make, like:
 295  *   make all CFLAGS="-DSCM_ENABLE_XXX=1 ..."
 296  */
 297
 298 /* If SCM_ENABLE_DEPRECATED is set to 1, deprecated code will be included in
 299  * guile, as well as some functions to issue run-time warnings about uses of
 300  * deprecated functions.
 301  */
 302 #ifndef SCM_ENABLE_DEPRECATED
 303 #define SCM_ENABLE_DEPRECATED 0
 304 #endif
 305
 306 \f
 307
 308 /* {Architecture and compiler properties}
 309  *
 310  * Guile as of today can only work on systems which fulfill at least the
 311  * following requirements:
 312  *
 313  * - scm_t_bits and SCM variables have at least 32 bits.
 314  *   Guile's type system is based on this assumption.
 315  *
 316  * - sizeof (scm_t_bits) >= sizeof (void*) and sizeof (SCM) >= sizeof (void*)
 317  *   Guile's type system is based on this assumption, since it must be
 318  *   possible to store pointers to cells on the heap in scm_t_bits and SCM
 319  *   variables.
 320  *
 321  * - sizeof (scm_t_bits) >= 4 and sizeof (scm_t_bits) is a power of 2.
 322  *   Guile's type system is based on this assumption.  In particular, it is
 323  *   assumed that cells, i. e. pairs of scm_t_bits variables, are eight
 324  *   character aligned.  This is because three bits of a scm_t_bits variable
 325  *   that is holding a pointer to a cell on the heap must be available for
 326  *   storing type data.
 327  *
 328  * - sizeof (scm_t_bits) <= sizeof (void*) and sizeof (SCM) <= sizeof (void*)
 329  *   In some parts of guile, scm_t_bits and SCM variables are passed to
 330  *   functions as void* arguments.  Together with the requirement above, this
 331  *   requires a one-to-one correspondence between the size of a void* and the
 332  *   sizes of scm_t_bits and SCM variables.
 333  *
 334  * - numbers are encoded using two's complement.
 335  *   The implementation of the bitwise scheme level operations is based on
 336  *   this assumption.
 337  *
 338  * - ... add more
 339  */
 340
 341 #ifdef CHAR_BIT
 342 # define SCM_CHAR_BIT CHAR_BIT
 343 #else
 344 # define SCM_CHAR_BIT 8
 345 #endif
 346
 347 #ifdef LONG_BIT
 348 # define SCM_LONG_BIT LONG_BIT
 349 #else
 350 # define SCM_LONG_BIT (SCM_CHAR_BIT * sizeof (long) / sizeof (char))
 351 #endif
 352
 353 #ifdef UCHAR_MAX
 354 # define SCM_CHAR_CODE_LIMIT (UCHAR_MAX + 1L)
 355 #else
 356 # define SCM_CHAR_CODE_LIMIT 256L
 357 #endif
 358
 359 #define SCM_I_UTYPE_MAX(type)      ((type)-1)
 360 #define SCM_I_TYPE_MAX(type,umax)  ((type)((umax)/2))
 361 #define SCM_I_TYPE_MIN(type,umax)  (-((type)((umax)/2))-1)
 362
 363 #define SCM_T_UINT8_MAX   SCM_I_UTYPE_MAX(scm_t_uint8)
 364 #define SCM_T_INT8_MIN    SCM_I_TYPE_MIN(scm_t_int8,SCM_T_UINT8_MAX)
 365 #define SCM_T_INT8_MAX    SCM_I_TYPE_MAX(scm_t_int8,SCM_T_UINT8_MAX)
 366
 367 #define SCM_T_UINT16_MAX  SCM_I_UTYPE_MAX(scm_t_uint16)
 368 #define SCM_T_INT16_MIN   SCM_I_TYPE_MIN(scm_t_int16,SCM_T_UINT16_MAX)
 369 #define SCM_T_INT16_MAX   SCM_I_TYPE_MAX(scm_t_int16,SCM_T_UINT16_MAX)
 370
 371 #define SCM_T_UINT32_MAX  SCM_I_UTYPE_MAX(scm_t_uint32)
 372 #define SCM_T_INT32_MIN   SCM_I_TYPE_MIN(scm_t_int32,SCM_T_UINT32_MAX)
 373 #define SCM_T_INT32_MAX   SCM_I_TYPE_MAX(scm_t_int32,SCM_T_UINT32_MAX)
 374
 375 #if SCM_HAVE_T_INT64
 376 #define SCM_T_UINT64_MAX  SCM_I_UTYPE_MAX(scm_t_uint64)
 377 #define SCM_T_INT64_MIN   SCM_I_TYPE_MIN(scm_t_int64,SCM_T_UINT64_MAX)
 378 #define SCM_T_INT64_MAX   SCM_I_TYPE_MAX(scm_t_int64,SCM_T_UINT64_MAX)
 379 #endif
 380
 381 #if SCM_SIZEOF_LONG_LONG
 382 #define SCM_I_ULLONG_MAX  SCM_I_UTYPE_MAX(unsigned long long)
 383 #define SCM_I_LLONG_MIN   SCM_I_TYPE_MIN(long long,SCM_I_ULLONG_MAX)
 384 #define SCM_I_LLONG_MAX   SCM_I_TYPE_MAX(long long,SCM_I_ULLONG_MAX)
 385 #endif
 386
 387 #define SCM_T_UINTMAX_MAX SCM_I_UTYPE_MAX(scm_t_uintmax)
 388 #define SCM_T_INTMAX_MIN  SCM_I_TYPE_MIN(scm_t_intmax,SCM_T_UINTMAX_MAX)
 389 #define SCM_T_INTMAX_MAX  SCM_I_TYPE_MAX(scm_t_intmax,SCM_T_UINTMAX_MAX)
 390
 391 #define SCM_I_SIZE_MAX    SCM_I_UTYPE_MAX(size_t)
 392 #define SCM_I_SSIZE_MIN   SCM_I_TYPE_MIN(ssize_t,SCM_I_SIZE_MAX)
 393 #define SCM_I_SSIZE_MAX   SCM_I_TYPE_MAX(ssize_t,SCM_I_SIZE_MAX)
 394
 395 \f
 396
 397 #include "libguile/tags.h"
 398
 399 \f
 400 #ifdef vms
 401 # ifndef CHEAP_CONTINUATIONS
 402    typedef int jmp_buf[17];
 403    extern int setjump(jmp_buf env);
 404    extern int longjump(jmp_buf env, int ret);
 405 #  define setjmp setjump
 406 #  define longjmp longjump
 407 # else
 408 #  include <setjmp.h>
 409 # endif
 410 #else                           /* ndef vms */
 411 # ifdef _CRAY1
 412     typedef int jmp_buf[112];
 413     extern int setjump(jmp_buf env);
 414     extern int longjump(jmp_buf env, int ret);
 415 #  define setjmp setjump
 416 #  define longjmp longjump
 417 # else                          /* ndef _CRAY1 */
 418 #  if defined (__ia64__)
 419 /* For IA64, emulate the setjmp API using getcontext. */
 420 #   include <signal.h>
 421 #   include <ucontext.h>
 422     typedef struct {
 423       ucontext_t ctx;
 424       int fresh;
 425     } jmp_buf;
 426 #   define setjmp(JB)                                   \
 427       ( (JB).fresh = 1,                                 \
 428         getcontext (&((JB).ctx)),                       \
 429         ((JB).fresh ? ((JB).fresh = 0, 0) : 1) )
 430 #   define longjmp(JB,VAL) scm_ia64_longjmp (&(JB), VAL)
 431     void scm_ia64_longjmp (jmp_buf *, int);
 432 #  else                         /* ndef __ia64__ */
 433 #   include <setjmp.h>
 434 #  endif                        /* ndef __ia64__ */
 435 # endif                         /* ndef _CRAY1 */
 436 #endif                          /* ndef vms */
 437
 438 /* James Clark came up with this neat one instruction fix for
 439  * continuations on the SPARC.  It flushes the register windows so
 440  * that all the state of the process is contained in the stack.
 441  */
 442
 443 #if defined (sparc) || defined (__sparc__) || defined (__sparc)
 444 # define SCM_FLUSH_REGISTER_WINDOWS asm("ta 3")
 445 #else
 446 # define SCM_FLUSH_REGISTER_WINDOWS /* empty */
 447 #endif
 448
 449 /* If stack is not longword aligned then
 450  */
 451
 452 /* #define SHORT_ALIGN */
 453 #ifdef THINK_C
 454 # define SHORT_ALIGN
 455 #endif
 456 #ifdef MSDOS
 457 # define SHORT_ALIGN
 458 #endif
 459 #ifdef atarist
 460 # define SHORT_ALIGN
 461 #endif
 462
 463 #ifdef SHORT_ALIGN
 464 typedef short SCM_STACKITEM;
 465 #else
 466 typedef long SCM_STACKITEM;
 467 #endif
 468
 469 /* Cast pointer through (void *) in order to avoid compiler warnings
 470    when strict aliasing is enabled */
 471 #define SCM_STACK_PTR(ptr) ((SCM_STACKITEM *) (void *) (ptr))
 472 \f
 473
 474 #define SCM_ASYNC_TICK /*fixme* should change names */ \
 475 do { \
 476   if (SCM_I_CURRENT_THREAD->pending_asyncs) \
 477     scm_async_click (); \
 478 } while (0)
 479
 480
 481 /* Anthony Green writes:
 482    When the compiler sees...
 483            DEFER_INTS;
 484            [critical code here]
 485            ALLOW_INTS;
 486    ...it doesn't actually promise to keep the critical code within the
 487    boundries of the DEFER/ALLOW_INTS instructions. It may very well
 488    schedule it outside of the magic defined in those macros.
 489
 490    However, GCC's volatile asm feature forms a barrier over which code is
 491    never moved. So if you add...
 492            asm ("");
 493    ...to each of the DEFER_INTS and ALLOW_INTS macros, the critical
 494    code will always remain in place.  asm's without inputs or outputs
 495    are implicitly volatile. */
 496 #ifdef __GNUC__
 497 #define SCM_FENCE asm /* volatile */ ("")
 498 #elif defined (__INTEL_COMPILER) && defined (__ia64)
 499 #define SCM_FENCE __memory_barrier()
 500 #else
 501 #define SCM_FENCE
 502 #endif
 503
 504 #define SCM_TICK \
 505 do { \
 506   SCM_ASYNC_TICK; \
 507   SCM_THREAD_SWITCHING_CODE; \
 508 } while (0)
 509
 510 \f
 511
 512 /** SCM_ASSERT
 513  **
 514  **/
 515
 516
 517 #ifdef SCM_RECKLESS
 518 #define SCM_ASSERT(_cond, _arg, _pos, _subr)
 519 #define SCM_ASSERT_TYPE(_cond, _arg, _pos, _subr, _msg)
 520 #define SCM_ASRTGO(_cond, _label)
 521 #else
 522 #define SCM_ASSERT(_cond, _arg, _pos, _subr)                    \
 523         do { if (SCM_UNLIKELY (!(_cond)))                       \
 524           scm_wrong_type_arg (_subr, _pos, _arg); } while (0)
 525 #define SCM_ASSERT_TYPE(_cond, _arg, _pos, _subr, _msg)                 \
 526         do { if (SCM_UNLIKELY (!(_cond)))                               \
 527           scm_wrong_type_arg_msg(_subr, _pos, _arg, _msg);  } while (0)
 528 #define SCM_ASRTGO(_cond, _label)               \
 529         do {  if (SCM_UNLIKELY (!(_cond)))      \
 530           goto _label; } while (0)
 531 #endif
 532
 533 /*
 534  * SCM_WTA_DISPATCH
 535  */
 536
 537 /* Dirk:FIXME:: In all of the SCM_WTA_DISPATCH_* macros it is assumed that
 538  * 'gf' is zero if uninitialized.  It would be cleaner if some valid SCM value
 539  * like SCM_BOOL_F or SCM_UNDEFINED was chosen.
 540  */
 541
 542 SCM_API SCM scm_call_generic_0 (SCM gf);
 543
 544 #define SCM_WTA_DISPATCH_0(gf, subr)                            \
 545   return (SCM_UNPACK (gf)                                       \
 546           ? scm_call_generic_0 ((gf))                           \
 547           : (scm_error_num_args_subr ((subr)), SCM_UNSPECIFIED))
 548 #define SCM_GASSERT0(cond, gf, subr)            \
 549   if (SCM_UNLIKELY(!(cond)))            \
 550     SCM_WTA_DISPATCH_0((gf), (subr))
 551
 552 SCM_API SCM scm_call_generic_1 (SCM gf, SCM a1);
 553
 554 #define SCM_WTA_DISPATCH_1(gf, a1, pos, subr)                   \
 555   return (SCM_UNPACK (gf)                                       \
 556           ? scm_call_generic_1 ((gf), (a1))                     \
 557           : (scm_wrong_type_arg ((subr), (pos), (a1)), SCM_UNSPECIFIED))
 558 #define SCM_GASSERT1(cond, gf, a1, pos, subr)           \
 559   if (SCM_UNLIKELY (!(cond)))                   \
 560     SCM_WTA_DISPATCH_1((gf), (a1), (pos), (subr))
 561
 562 SCM_API SCM scm_call_generic_2 (SCM gf, SCM a1, SCM a2);
 563
 564 #define SCM_WTA_DISPATCH_2(gf, a1, a2, pos, subr)                       \
 565   return (SCM_UNPACK (gf)                                               \
 566           ? scm_call_generic_2 ((gf), (a1), (a2))                       \
 567           : (scm_wrong_type_arg ((subr), (pos),                         \
 568                                  (pos) == SCM_ARG1 ? (a1) : (a2)),      \
 569              SCM_UNSPECIFIED))
 570 #define SCM_GASSERT2(cond, gf, a1, a2, pos, subr)       \
 571   if (SCM_UNLIKELY (!(cond)))                   \
 572     SCM_WTA_DISPATCH_2((gf), (a1), (a2), (pos), (subr))
 573
 574 SCM_API SCM scm_apply_generic (SCM gf, SCM args);
 575
 576 #define SCM_WTA_DISPATCH_n(gf, args, pos, subr)                           \
 577   return (SCM_UNPACK (gf)                                                 \
 578           ? scm_apply_generic ((gf), (args))                              \
 579           : (scm_wrong_type_arg ((subr), (pos),                           \
 580                                  scm_list_ref ((args),                    \
 581                                                scm_from_int ((pos) - 1))), \
 582              SCM_UNSPECIFIED))
 583 #define SCM_GASSERTn(cond, gf, args, pos, subr)         \
 584   if (SCM_UNLIKELY (!(cond)))                   \
 585     SCM_WTA_DISPATCH_n((gf), (args), (pos), (subr))
 586
 587 #ifndef SCM_MAGIC_SNARFER
 588 /* Let these macros pass through if
 589    we are snarfing;  thus we can tell the
 590    difference between the use of an actual
 591    number vs. the use of one of these macros --
 592    actual numbers in SCM_VALIDATE_* and SCM_ASSERT
 593    constructs must match the formal argument name,
 594    but using SCM_ARG* avoids the test */
 595
 596 #define SCM_ARGn                0
 597 #define SCM_ARG1                1
 598 #define SCM_ARG2                2
 599 #define SCM_ARG3                3
 600 #define SCM_ARG4                4
 601 #define SCM_ARG5                5
 602 #define SCM_ARG6                6
 603 #define SCM_ARG7                7
 604
 605 #endif /* SCM_MAGIC_SNARFER */
 606
 607 \f
 608
 609 /* SCM_EXIT_SUCCESS is the default code to return from SCM if no errors
 610  * were encountered.  SCM_EXIT_FAILURE is the default code to return from
 611  * SCM if errors were encountered.  The return code can be explicitly
 612  * specified in a SCM program with (scm_quit <n>).
 613  */
 614
 615 #ifndef SCM_EXIT_SUCCESS
 616 #ifdef vms
 617 #define SCM_EXIT_SUCCESS 1
 618 #else
 619 #define SCM_EXIT_SUCCESS 0
 620 #endif /* def vms */
 621 #endif /* ndef SCM_EXIT_SUCCESS */
 622 #ifndef SCM_EXIT_FAILURE
 623 #ifdef vms
 624 #define SCM_EXIT_FAILURE 2
 625 #else
 626 #define SCM_EXIT_FAILURE 1
 627 #endif /* def vms */
 628 #endif /* ndef SCM_EXIT_FAILURE */
 629
 630 /* Define SCM_C_INLINE_KEYWORD so that it can be used as a replacement
 631    for the "inline" keyword, expanding to nothing when "inline" is not
 632    available.
 633 */
 634
 635 #ifdef SCM_C_INLINE
 636 #define SCM_C_INLINE_KEYWORD SCM_C_INLINE
 637 #else
 638 #define SCM_C_INLINE_KEYWORD
 639 #endif
 640
 641 #endif  /* SCM___SCM_H */
 642
 643 /*
 644   Local Variables:
 645   c-file-style: "gnu"
 646   End:
 647 */