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 License
  10  * as published by the Free Software Foundation; either version 3 of
  11  * the License, or (at your option) any later version.
  12  *
  13  * This library is distributed in the hope that it will be useful, but
  14  * 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
  21  * 02110-1301 USA
  22  */
  23
  24 \f
  25
  26 /**********************************************************************
  27  This file is Guile's central public header.
  28
  29  When included by other files, this file should preceed any include
  30  other than __scm.h.
  31
  32  Under *NO* circumstances should new items be added to the global
  33  namespace (via adding #define, typedef, or similar to this file) with
  34  generic names.  This usually means that any new names should be
  35  prefixed by either SCM_ or GUILE_.  i.e. do *not* #define HAVE_FOO or
  36  SIZEOF_BAR.  See configure.in, gen-scmconfig.h.in, and
  37  gen-scmconfig.c for examples of how to properly handle this issue.
  38  The main documentation is in gen-scmconfig.c.
  39
  40  "What's the difference between _scm.h and __scm.h?"
  41
  42    _scm.h is not installed; it's only visible to the libguile sources
  43    themselves, and it includes config.h, the private config header.
  44
  45    __scm.h is installed, and is #included by <libguile.h>.  If both
  46    the client and libguile need some piece of information, and it
  47    doesn't fit well into the header file for any particular module, it
  48    should go in __scm.h.  __scm.h includes scmconfig.h, the public
  49    config header.
  50  **********************************************************************/
  51
  52 /* What did the configure script discover about the outside world?  */
  53 #include "libguile/scmconfig.h"
  54
  55 \f
  56
  57 /* {Compiler hints}
  58  *
  59  * The following macros are used to provide additional information for the
  60  * compiler, which may help to do better error checking and code
  61  * optimization.  A second benefit of these macros is, that they also provide
  62  * additional information to the developers.
  63  */
  64
  65 /* The macro SCM_NORETURN indicates that a function will never return.
  66  * Examples:
  67  *   1) int foo (char arg) SCM_NORETURN;
  68  */
  69 #ifdef __GNUC__
  70 #define SCM_NORETURN __attribute__ ((noreturn))
  71 #else
  72 #define SCM_NORETURN
  73 #endif
  74
  75 /* The macro SCM_UNUSED indicates that a function, function argument or
  76  * variable may potentially be unused.
  77  * Examples:
  78  *   1) static int unused_function (char arg) SCM_UNUSED;
  79  *   2) int foo (char unused_argument SCM_UNUSED);
  80  *   3) int unused_variable SCM_UNUSED;
  81  */
  82 #ifdef __GNUC__
  83 #define SCM_UNUSED __attribute__ ((unused))
  84 #else
  85 #define SCM_UNUSED
  86 #endif
  87
  88
  89 /* The SCM_EXPECT macros provide branch prediction hints to the compiler.  To
  90  * use only in places where the result of the expression under "normal"
  91  * circumstances is known.  */
  92 #if defined(__GNUC__) && (__GNUC__ >= 3)
  93 # define SCM_EXPECT    __builtin_expect
  94 #else
  95 # define SCM_EXPECT(_expr, _value) (_expr)
  96 #endif
  97
  98 #define SCM_LIKELY(_expr)    SCM_EXPECT ((_expr), 1)
  99 #define SCM_UNLIKELY(_expr)  SCM_EXPECT ((_expr), 0)
 100
 101 /* The SCM_INTERNAL macro makes it possible to explicitly declare a function
 102  * as having "internal" linkage.  However our current tack on this problem is
 103  * to use GCC 4's -fvisibility=hidden, making functions internal by default,
 104  * and then SCM_API marks them for export. */
 105 #define SCM_INTERNAL  extern
 106
 107 /* The SCM_DEPRECATED macro is used in declarations of deprecated functions
 108  * or variables.  Defining `SCM_BUILDING_DEPRECATED_CODE' allows deprecated
 109  * functions to be implemented in terms of deprecated functions, and allows
 110  * deprecated functions to be referred to by `scm_c_define_gsubr ()'.  */
 111 #if !defined (SCM_BUILDING_DEPRECATED_CODE)     \
 112     && defined (__GNUC__) && (__GNUC__ >= 3)
 113 # define SCM_DEPRECATED  SCM_API __attribute__ ((__deprecated__))
 114 #else
 115 # define SCM_DEPRECATED  SCM_API
 116 #endif
 117
 118 /* The SCM_ALIGNED macro, when defined, can be used to instruct the compiler
 119  * to honor the given alignment constraint.  */
 120 #if defined __GNUC__
 121 # define SCM_ALIGNED(x)  __attribute__ ((aligned (x)))
 122 #elif defined __INTEL_COMPILER
 123 # define SCM_ALIGNED(x)  __declspec (align (x))
 124 #else
 125 /* Don't know how to align things.  */
 126 # undef SCM_ALIGNED
 127 #endif
 128
 129 \f
 130 /* {Supported Options}
 131  *
 132  * These may be defined or undefined.
 133  */
 134
 135 /* #define GUILE_DEBUG_FREELIST */
 136
 137 /* All the number support there is.
 138  */
 139 #define BIGNUMS
 140
 141 /* GC should relinquish empty cons-pair arenas. */
 142 /* cmm:FIXME look at this after done mangling the GC */
 143 /* #define GC_FREE_SEGMENTS */
 144
 145 /* Provide a scheme-accessible count-down timer that
 146  * generates a pseudo-interrupt.
 147  */
 148 #define TICKS
 149
 150
 151 /* Use engineering notation when converting numbers strings?
 152  */
 153 #undef ENGNOT
 154
 155 \f
 156 /* {Unsupported Options}
 157  *
 158  * These must be defined as given here.
 159  */
 160
 161
 162 /* Guile Scheme supports the #f/() distinction; Guile Lisp won't.  We
 163    have horrible plans for their unification.  */
 164 #undef SICP
 165
 166 \f
 167
 168 /* Random options (not yet supported or in final form). */
 169
 170 #define STACK_CHECKING
 171 #undef NO_CEVAL_STACK_CHECKING
 172
 173 \f
 174
 175 /* SCM_API is a macro prepended to all function and data definitions
 176    which should be exported from libguile. */
 177
 178 #if BUILDING_LIBGUILE && HAVE_VISIBILITY
 179 # define SCM_API extern __attribute__((__visibility__("default")))
 180 #elif BUILDING_LIBGUILE && defined _MSC_VER
 181 # define SCM_API __declspec(dllexport) extern
 182 #elif defined _MSC_VER
 183 # define SCM_API __declspec(dllimport) extern
 184 #else
 185 # define SCM_API extern
 186 #endif
 187
 188 \f
 189
 190 /* {Debugging Options}
 191  *
 192  * These compile time options determine whether to include code that is only
 193  * useful for debugging guile itself or C level extensions to guile.  The
 194  * common prefix for all option macros of this kind is "SCM_DEBUG_".  It is
 195  * guaranteed that a macro named SCM_DEBUG_XXX is always defined (typically to
 196  * either 0 or 1), i. e. there is no need to test for the undefined case.
 197  * This allows to use these definitions comfortably within code, as in the
 198  * following example:
 199  *   #define FOO do { if (SCM_DEBUG_XXX) bar(); else baz(); } while (0)
 200  * Any sane compiler will remove the unused branch without any performance
 201  * penalty for the resulting code.
 202  *
 203  * Note:  Some SCM_DEBUG_XXX options are not settable at configure time.
 204  * To change the value of such options you will have to edit this header
 205  * file or give suitable options to make, like:
 206  *   make all CFLAGS="-DSCM_DEBUG_XXX=1 ..."
 207  */
 208
 209
 210 /* The value of SCM_DEBUG determines the default for most of the not yet
 211  * defined debugging options.  This allows, for example, to enable most of the
 212  * debugging options by simply defining SCM_DEBUG as 1.
 213  */
 214 #ifndef SCM_DEBUG
 215 #define SCM_DEBUG 0
 216 #endif
 217
 218 /* For debugging purposes: define this is to ensure nobody is using
 219  * the mark bits outside of the marking phase.  This is meant for
 220  * debugging purposes only.
 221  */
 222 #ifndef SCM_DEBUG_MARKING_API
 223 #define SCM_DEBUG_MARKING_API 0
 224 #endif
 225
 226 /* If SCM_DEBUG_CELL_ACCESSES is set to 1, cell accesses will perform
 227  * exhaustive parameter checking:  It will be verified that cell parameters
 228  * actually point to a valid heap cell.  Note:  If this option is enabled,
 229  * guile will run about ten times slower than normally.
 230  */
 231 #ifndef SCM_DEBUG_CELL_ACCESSES
 232 #define SCM_DEBUG_CELL_ACCESSES SCM_DEBUG
 233 #endif
 234
 235 /* If SCM_DEBUG_INTERRUPTS is set to 1, with every deferring and allowing of
 236  * interrupts a consistency check will be performed.
 237  */
 238 #ifndef SCM_DEBUG_INTERRUPTS
 239 #define SCM_DEBUG_INTERRUPTS SCM_DEBUG
 240 #endif
 241
 242 /* If SCM_DEBUG_PAIR_ACCESSES is set to 1, accesses to cons cells will be
 243  * exhaustively checked.  Note:  If this option is enabled, guile will run
 244  * slower than normally.
 245  */
 246 #ifndef SCM_DEBUG_PAIR_ACCESSES
 247 #define SCM_DEBUG_PAIR_ACCESSES SCM_DEBUG
 248 #endif
 249
 250 /* If SCM_DEBUG_REST_ARGUMENT is set to 1, functions that take rest arguments
 251  * will check whether the rest arguments are actually passed as a proper list.
 252  * Otherwise, if SCM_DEBUG_REST_ARGUMENT is 0, functions that take rest
 253  * arguments will take it for granted that these are passed as a proper list.
 254  */
 255 #ifndef SCM_DEBUG_REST_ARGUMENT
 256 #define SCM_DEBUG_REST_ARGUMENT SCM_DEBUG
 257 #endif
 258
 259 /* The macro SCM_DEBUG_TYPING_STRICTNESS indicates what level of type checking
 260  * shall be performed with respect to the use of the SCM datatype.  The macro
 261  * may be defined to one of the values 0, 1 and 2.
 262  *
 263  * A value of 0 means that there will be no compile time type checking, since
 264  * the SCM datatype will be declared as an integral type.  This setting should
 265  * only be used on systems, where casting from integral types to pointers may
 266  * lead to loss of bit information.
 267  *
 268  * A value of 1 means that there will an intermediate level of compile time
 269  * type checking, since the SCM datatype will be declared as a pointer to an
 270  * undefined struct.  This setting is the default, since it does not cost
 271  * anything in terms of performance or code size.
 272  *
 273  * A value of 2 provides a maximum level of compile time type checking since
 274  * the SCM datatype will be declared as a struct.  This setting should be used
 275  * for _compile time_ type checking only, since the compiled result is likely
 276  * to be quite inefficient.  The right way to make use of this option is to do
 277  * a 'make clean; make CFLAGS=-DSCM_DEBUG_TYPING_STRICTNESS=2', fix your
 278  * errors, and then do 'make clean; make'.
 279  */
 280 #ifndef SCM_DEBUG_TYPING_STRICTNESS
 281 #define SCM_DEBUG_TYPING_STRICTNESS 1
 282 #endif
 283
 284 /* If SCM_DEBUG_DEBUGGING_SUPPORT is set to 1, guile will provide a set of
 285  * special functions that support debugging with a debugger like gdb or
 286  * debugging of guile internals on the scheme level.  The behaviour of guile
 287  * is not changed by this macro, only the set of functions that are available
 288  * will differ.  All functions that are introduced this way have the prefix
 289  * 'scm_dbg_' on the C level and the prefix 'dbg-' on the scheme level.  This
 290  * allows to easily determine the set of support functions, given that your
 291  * debugger or repl provide automatic name completion.  Note that these
 292  * functions are intended to be used during interactive debugging sessions
 293  * only.  They are not considered part of guile's official API.  They may
 294  * change or disappear without notice or deprecation phase.
 295  */
 296 #ifndef SCM_DEBUG_DEBUGGING_SUPPORT
 297 #define SCM_DEBUG_DEBUGGING_SUPPORT SCM_DEBUG
 298 #endif
 299
 300 \f
 301
 302 /* {Feature Options}
 303  *
 304  * These compile time options determine whether code for certain features
 305  * should be compiled into guile.  The common prefix for all option macros
 306  * of this kind is "SCM_ENABLE_".  It is guaranteed that a macro named
 307  * SCM_ENABLE_XXX is defined to be either 0 or 1, i. e. there is no need to
 308  * test for the undefined case.  This allows to use these definitions
 309  * comfortably within code, as in the following example:
 310  *   #define FOO do { if (SCM_ENABLE_XXX) bar(); else baz(); } while (0)
 311  * Any sane compiler will remove the unused branch without any performance
 312  * penalty for the resulting code.
 313  *
 314  * Note:  Some SCM_ENABLE_XXX options are not settable at configure time.
 315  * To change the value of such options you will have to edit this header
 316  * file or give suitable options to make, like:
 317  *   make all CFLAGS="-DSCM_ENABLE_XXX=1 ..."
 318  */
 319
 320 /* If SCM_ENABLE_DEPRECATED is set to 1, deprecated code will be included in
 321  * guile, as well as some functions to issue run-time warnings about uses of
 322  * deprecated functions.
 323  */
 324 #ifndef SCM_ENABLE_DEPRECATED
 325 #define SCM_ENABLE_DEPRECATED 0
 326 #endif
 327
 328 \f
 329
 330 /* {Architecture and compiler properties}
 331  *
 332  * Guile as of today can only work on systems which fulfill at least the
 333  * following requirements:
 334  *
 335  * - scm_t_bits and SCM variables have at least 32 bits.
 336  *   Guile's type system is based on this assumption.
 337  *
 338  * - sizeof (scm_t_bits) >= sizeof (void*) and sizeof (SCM) >= sizeof (void*)
 339  *   Guile's type system is based on this assumption, since it must be
 340  *   possible to store pointers to cells on the heap in scm_t_bits and SCM
 341  *   variables.
 342  *
 343  * - sizeof (scm_t_bits) >= 4 and sizeof (scm_t_bits) is a power of 2.
 344  *   Guile's type system is based on this assumption.  In particular, it is
 345  *   assumed that cells, i. e. pairs of scm_t_bits variables, are eight
 346  *   character aligned.  This is because three bits of a scm_t_bits variable
 347  *   that is holding a pointer to a cell on the heap must be available for
 348  *   storing type data.
 349  *
 350  * - sizeof (scm_t_bits) <= sizeof (void*) and sizeof (SCM) <= sizeof (void*)
 351  *   In some parts of guile, scm_t_bits and SCM variables are passed to
 352  *   functions as void* arguments.  Together with the requirement above, this
 353  *   requires a one-to-one correspondence between the size of a void* and the
 354  *   sizes of scm_t_bits and SCM variables.
 355  *
 356  * - numbers are encoded using two's complement.
 357  *   The implementation of the bitwise scheme level operations is based on
 358  *   this assumption.
 359  *
 360  * - ... add more
 361  */
 362
 363 #ifdef CHAR_BIT
 364 # define SCM_CHAR_BIT CHAR_BIT
 365 #else
 366 # define SCM_CHAR_BIT 8
 367 #endif
 368
 369 #ifdef LONG_BIT
 370 # define SCM_LONG_BIT LONG_BIT
 371 #else
 372 # define SCM_LONG_BIT (SCM_CHAR_BIT * sizeof (long) / sizeof (char))
 373 #endif
 374
 375 #ifdef UCHAR_MAX
 376 # define SCM_CHAR_CODE_LIMIT (UCHAR_MAX + 1L)
 377 #else
 378 # define SCM_CHAR_CODE_LIMIT 256L
 379 #endif
 380
 381 #define SCM_I_UTYPE_MAX(type)      ((type)-1)
 382 #define SCM_I_TYPE_MAX(type,umax)  ((type)((umax)/2))
 383 #define SCM_I_TYPE_MIN(type,umax)  (-((type)((umax)/2))-1)
 384
 385 #define SCM_T_UINT8_MAX   SCM_I_UTYPE_MAX(scm_t_uint8)
 386 #define SCM_T_INT8_MIN    SCM_I_TYPE_MIN(scm_t_int8,SCM_T_UINT8_MAX)
 387 #define SCM_T_INT8_MAX    SCM_I_TYPE_MAX(scm_t_int8,SCM_T_UINT8_MAX)
 388
 389 #define SCM_T_UINT16_MAX  SCM_I_UTYPE_MAX(scm_t_uint16)
 390 #define SCM_T_INT16_MIN   SCM_I_TYPE_MIN(scm_t_int16,SCM_T_UINT16_MAX)
 391 #define SCM_T_INT16_MAX   SCM_I_TYPE_MAX(scm_t_int16,SCM_T_UINT16_MAX)
 392
 393 #define SCM_T_UINT32_MAX  SCM_I_UTYPE_MAX(scm_t_uint32)
 394 #define SCM_T_INT32_MIN   SCM_I_TYPE_MIN(scm_t_int32,SCM_T_UINT32_MAX)
 395 #define SCM_T_INT32_MAX   SCM_I_TYPE_MAX(scm_t_int32,SCM_T_UINT32_MAX)
 396
 397 #if SCM_HAVE_T_INT64
 398 #define SCM_T_UINT64_MAX  SCM_I_UTYPE_MAX(scm_t_uint64)
 399 #define SCM_T_INT64_MIN   SCM_I_TYPE_MIN(scm_t_int64,SCM_T_UINT64_MAX)
 400 #define SCM_T_INT64_MAX   SCM_I_TYPE_MAX(scm_t_int64,SCM_T_UINT64_MAX)
 401 #endif
 402
 403 #if SCM_SIZEOF_LONG_LONG
 404 #define SCM_I_ULLONG_MAX  SCM_I_UTYPE_MAX(unsigned long long)
 405 #define SCM_I_LLONG_MIN   SCM_I_TYPE_MIN(long long,SCM_I_ULLONG_MAX)
 406 #define SCM_I_LLONG_MAX   SCM_I_TYPE_MAX(long long,SCM_I_ULLONG_MAX)
 407 #endif
 408
 409 #define SCM_T_UINTMAX_MAX SCM_I_UTYPE_MAX(scm_t_uintmax)
 410 #define SCM_T_INTMAX_MIN  SCM_I_TYPE_MIN(scm_t_intmax,SCM_T_UINTMAX_MAX)
 411 #define SCM_T_INTMAX_MAX  SCM_I_TYPE_MAX(scm_t_intmax,SCM_T_UINTMAX_MAX)
 412
 413 #define SCM_I_SIZE_MAX    SCM_I_UTYPE_MAX(size_t)
 414 #define SCM_I_SSIZE_MIN   SCM_I_TYPE_MIN(ssize_t,SCM_I_SIZE_MAX)
 415 #define SCM_I_SSIZE_MAX   SCM_I_TYPE_MAX(ssize_t,SCM_I_SIZE_MAX)
 416
 417 \f
 418
 419 #include "libguile/tags.h"
 420
 421 \f
 422 #ifdef vms
 423 # ifndef CHEAP_CONTINUATIONS
 424    typedef int jmp_buf[17];
 425    extern int setjump(jmp_buf env);
 426    extern int longjump(jmp_buf env, int ret);
 427 #  define setjmp setjump
 428 #  define longjmp longjump
 429 # else
 430 #  include <setjmp.h>
 431 # endif
 432 #else                           /* ndef vms */
 433 # ifdef _CRAY1
 434     typedef int jmp_buf[112];
 435     extern int setjump(jmp_buf env);
 436     extern int longjump(jmp_buf env, int ret);
 437 #  define setjmp setjump
 438 #  define longjmp longjump
 439 # else                          /* ndef _CRAY1 */
 440 #  if defined (__ia64__)
 441 /* For IA64, emulate the setjmp API using getcontext. */
 442 #   include <signal.h>
 443 #   include <ucontext.h>
 444     typedef struct {
 445       ucontext_t ctx;
 446       int fresh;
 447     } scm_i_jmp_buf;
 448 #   define SCM_I_SETJMP(JB)                             \
 449       ( (JB).fresh = 1,                                 \
 450         getcontext (&((JB).ctx)),                       \
 451         ((JB).fresh ? ((JB).fresh = 0, 0) : 1) )
 452 #   define SCM_I_LONGJMP(JB,VAL) scm_ia64_longjmp (&(JB), VAL)
 453     void scm_ia64_longjmp (scm_i_jmp_buf *, int);
 454 #  else                         /* ndef __ia64__ */
 455 #   include <setjmp.h>
 456 #  endif                        /* ndef __ia64__ */
 457 # endif                         /* ndef _CRAY1 */
 458 #endif                          /* ndef vms */
 459
 460 /* For any platform where SCM_I_SETJMP hasn't been defined in some
 461    special way above, map SCM_I_SETJMP, SCM_I_LONGJMP and
 462    scm_i_jmp_buf to setjmp, longjmp and jmp_buf. */
 463 #ifndef SCM_I_SETJMP
 464 #define scm_i_jmp_buf jmp_buf
 465 #define SCM_I_SETJMP setjmp
 466 #define SCM_I_LONGJMP longjmp
 467 #endif
 468
 469 /* James Clark came up with this neat one instruction fix for
 470  * continuations on the SPARC.  It flushes the register windows so
 471  * that all the state of the process is contained in the stack.
 472  */
 473
 474 #if defined (sparc) || defined (__sparc__) || defined (__sparc)
 475 # define SCM_FLUSH_REGISTER_WINDOWS asm("ta 3")
 476 #else
 477 # define SCM_FLUSH_REGISTER_WINDOWS /* empty */
 478 #endif
 479
 480 /* If stack is not longword aligned then
 481  */
 482
 483 /* #define SHORT_ALIGN */
 484 #ifdef THINK_C
 485 # define SHORT_ALIGN
 486 #endif
 487 #ifdef MSDOS
 488 # define SHORT_ALIGN
 489 #endif
 490 #ifdef atarist
 491 # define SHORT_ALIGN
 492 #endif
 493
 494 #ifdef SHORT_ALIGN
 495 typedef short SCM_STACKITEM;
 496 #else
 497 typedef long SCM_STACKITEM;
 498 #endif
 499
 500 /* Cast pointer through (void *) in order to avoid compiler warnings
 501    when strict aliasing is enabled */
 502 #define SCM_STACK_PTR(ptr) ((SCM_STACKITEM *) (void *) (ptr))
 503 \f
 504
 505 SCM_API void scm_async_tick (void);
 506
 507 #ifdef BUILDING_LIBGUILE
 508
 509 /* FIXME: should change names */
 510 # define SCM_ASYNC_TICK                                 \
 511     do                                                  \
 512       {                                                 \
 513         if (SCM_I_CURRENT_THREAD->pending_asyncs)       \
 514           scm_async_click ();                           \
 515       }                                                 \
 516     while (0)
 517
 518 #else /* !BUILDING_LIBGUILE */
 519
 520 # define SCM_ASYNC_TICK  (scm_async_tick ())
 521
 522 #endif /* !BUILDING_LIBGUILE */
 523
 524
 525 /* Anthony Green writes:
 526    When the compiler sees...
 527            DEFER_INTS;
 528            [critical code here]
 529            ALLOW_INTS;
 530    ...it doesn't actually promise to keep the critical code within the
 531    boundries of the DEFER/ALLOW_INTS instructions. It may very well
 532    schedule it outside of the magic defined in those macros.
 533
 534    However, GCC's volatile asm feature forms a barrier over which code is
 535    never moved. So if you add...
 536            asm ("");
 537    ...to each of the DEFER_INTS and ALLOW_INTS macros, the critical
 538    code will always remain in place.  asm's without inputs or outputs
 539    are implicitly volatile. */
 540 #ifdef __GNUC__
 541 #define SCM_FENCE asm /* volatile */ ("")
 542 #elif defined (__INTEL_COMPILER) && defined (__ia64)
 543 #define SCM_FENCE __memory_barrier()
 544 #else
 545 #define SCM_FENCE
 546 #endif
 547
 548 #define SCM_TICK \
 549 do { \
 550   SCM_ASYNC_TICK; \
 551   SCM_THREAD_SWITCHING_CODE; \
 552 } while (0)
 553
 554 \f
 555
 556 /** SCM_ASSERT
 557  **
 558  **/
 559
 560
 561 #ifdef SCM_RECKLESS
 562 #define SCM_ASSERT(_cond, _arg, _pos, _subr)
 563 #define SCM_ASSERT_TYPE(_cond, _arg, _pos, _subr, _msg)
 564 #define SCM_ASRTGO(_cond, _label)
 565 #else
 566 #define SCM_ASSERT(_cond, _arg, _pos, _subr)                    \
 567         do { if (SCM_UNLIKELY (!(_cond)))                       \
 568           scm_wrong_type_arg (_subr, _pos, _arg); } while (0)
 569 #define SCM_ASSERT_TYPE(_cond, _arg, _pos, _subr, _msg)                 \
 570         do { if (SCM_UNLIKELY (!(_cond)))                               \
 571           scm_wrong_type_arg_msg(_subr, _pos, _arg, _msg);  } while (0)
 572 #define SCM_ASRTGO(_cond, _label)               \
 573         do {  if (SCM_UNLIKELY (!(_cond)))      \
 574           goto _label; } while (0)
 575 #endif
 576
 577 /*
 578  * SCM_WTA_DISPATCH
 579  */
 580
 581 /* Dirk:FIXME:: In all of the SCM_WTA_DISPATCH_* macros it is assumed that
 582  * 'gf' is zero if uninitialized.  It would be cleaner if some valid SCM value
 583  * like SCM_BOOL_F or SCM_UNDEFINED was chosen.
 584  */
 585
 586 SCM_API SCM scm_call_generic_0 (SCM gf);
 587
 588 #define SCM_WTA_DISPATCH_0(gf, subr)                            \
 589   return (SCM_UNPACK (gf)                                       \
 590           ? scm_call_generic_0 ((gf))                           \
 591           : (scm_error_num_args_subr ((subr)), SCM_UNSPECIFIED))
 592 #define SCM_GASSERT0(cond, gf, subr)            \
 593   if (SCM_UNLIKELY(!(cond)))            \
 594     SCM_WTA_DISPATCH_0((gf), (subr))
 595
 596 SCM_API SCM scm_call_generic_1 (SCM gf, SCM a1);
 597
 598 #define SCM_WTA_DISPATCH_1(gf, a1, pos, subr)                   \
 599   return (SCM_UNPACK (gf)                                       \
 600           ? scm_call_generic_1 ((gf), (a1))                     \
 601           : (scm_wrong_type_arg ((subr), (pos), (a1)), SCM_UNSPECIFIED))
 602
 603 /* This form is for dispatching a subroutine.  */
 604 #define SCM_WTA_DISPATCH_1_SUBR(subr, a1, pos)                          \
 605   return (SCM_UNPACK ((*SCM_SUBR_GENERIC (subr)))                       \
 606           ? scm_call_generic_1 ((*SCM_SUBR_GENERIC (subr)), (a1))       \
 607           : (scm_i_wrong_type_arg_symbol (SCM_SUBR_NAME (subr), (pos), (a1)), SCM_UNSPECIFIED))
 608
 609 #define SCM_GASSERT1(cond, gf, a1, pos, subr)           \
 610   if (SCM_UNLIKELY (!(cond)))                   \
 611     SCM_WTA_DISPATCH_1((gf), (a1), (pos), (subr))
 612
 613 SCM_API SCM scm_call_generic_2 (SCM gf, SCM a1, SCM a2);
 614
 615 #define SCM_WTA_DISPATCH_2(gf, a1, a2, pos, subr)                       \
 616   return (SCM_UNPACK (gf)                                               \
 617           ? scm_call_generic_2 ((gf), (a1), (a2))                       \
 618           : (scm_wrong_type_arg ((subr), (pos),                         \
 619                                  (pos) == SCM_ARG1 ? (a1) : (a2)),      \
 620              SCM_UNSPECIFIED))
 621 #define SCM_GASSERT2(cond, gf, a1, a2, pos, subr)       \
 622   if (SCM_UNLIKELY (!(cond)))                   \
 623     SCM_WTA_DISPATCH_2((gf), (a1), (a2), (pos), (subr))
 624
 625 SCM_API SCM scm_apply_generic (SCM gf, SCM args);
 626
 627 #define SCM_WTA_DISPATCH_n(gf, args, pos, subr)                           \
 628   return (SCM_UNPACK (gf)                                                 \
 629           ? scm_apply_generic ((gf), (args))                              \
 630           : (scm_wrong_type_arg ((subr), (pos),                           \
 631                                  scm_list_ref ((args),                    \
 632                                                scm_from_int ((pos) - 1))), \
 633              SCM_UNSPECIFIED))
 634 #define SCM_GASSERTn(cond, gf, args, pos, subr)         \
 635   if (SCM_UNLIKELY (!(cond)))                   \
 636     SCM_WTA_DISPATCH_n((gf), (args), (pos), (subr))
 637
 638 #ifndef SCM_MAGIC_SNARFER
 639 /* Let these macros pass through if
 640    we are snarfing;  thus we can tell the
 641    difference between the use of an actual
 642    number vs. the use of one of these macros --
 643    actual numbers in SCM_VALIDATE_* and SCM_ASSERT
 644    constructs must match the formal argument name,
 645    but using SCM_ARG* avoids the test */
 646
 647 #define SCM_ARGn                0
 648 #define SCM_ARG1                1
 649 #define SCM_ARG2                2
 650 #define SCM_ARG3                3
 651 #define SCM_ARG4                4
 652 #define SCM_ARG5                5
 653 #define SCM_ARG6                6
 654 #define SCM_ARG7                7
 655
 656 #endif /* SCM_MAGIC_SNARFER */
 657
 658 \f
 659
 660 /* SCM_EXIT_SUCCESS is the default code to return from SCM if no errors
 661  * were encountered.  SCM_EXIT_FAILURE is the default code to return from
 662  * SCM if errors were encountered.  The return code can be explicitly
 663  * specified in a SCM program with (scm_quit <n>).
 664  */
 665
 666 #ifndef SCM_EXIT_SUCCESS
 667 #ifdef vms
 668 #define SCM_EXIT_SUCCESS 1
 669 #else
 670 #define SCM_EXIT_SUCCESS 0
 671 #endif /* def vms */
 672 #endif /* ndef SCM_EXIT_SUCCESS */
 673 #ifndef SCM_EXIT_FAILURE
 674 #ifdef vms
 675 #define SCM_EXIT_FAILURE 2
 676 #else
 677 #define SCM_EXIT_FAILURE 1
 678 #endif /* def vms */
 679 #endif /* ndef SCM_EXIT_FAILURE */
 680
 681 /* Define SCM_C_INLINE_KEYWORD so that it can be used as a replacement
 682    for the "inline" keyword, expanding to nothing when "inline" is not
 683    available.
 684 */
 685
 686 #ifdef SCM_C_INLINE
 687 #define SCM_C_INLINE_KEYWORD SCM_C_INLINE
 688 #else
 689 #define SCM_C_INLINE_KEYWORD
 690 #endif
 691
 692 /* Handling thread-local storage (TLS).  */
 693
 694 #ifdef SCM_HAVE_THREAD_STORAGE_CLASS
 695 # define SCM_THREAD_LOCAL __thread
 696 #else
 697 # define SCM_THREAD_LOCAL
 698 #endif
 699
 700 #endif  /* SCM___SCM_H */
 701
 702 /*
 703   Local Variables:
 704   c-file-style: "gnu"
 705   End:
 706 */