malloc/obstack.h

   1 /* obstack.h - object stack macros
   2    Copyright (C) 1988,89,90,91,92,93,94,96,97 Free Software Foundation, Inc.
   3
   4    This file is part of the GNU C Library.  Its master source is NOT part of
   5    the C library, however.  The master source lives in /gd/gnu/lib.
   6
   7    The GNU C Library is free software; you can redistribute it and/or
   8    modify it under the terms of the GNU Library General Public License as
   9    published by the Free Software Foundation; either version 2 of the
  10    License, or (at your option) any later version.
  11
  12    The GNU C Library 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 GNU
  15    Library General Public License for more details.
  16
  17    You should have received a copy of the GNU Library General Public
  18    License along with the GNU C Library; see the file COPYING.LIB.  If not,
  19    write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
  20    Boston, MA 02111-1307, USA.  */
  21
  22 /* Summary:
  23
  24 All the apparent functions defined here are macros. The idea
  25 is that you would use these pre-tested macros to solve a
  26 very specific set of problems, and they would run fast.
  27 Caution: no side-effects in arguments please!! They may be
  28 evaluated MANY times!!
  29
  30 These macros operate a stack of objects.  Each object starts life
  31 small, and may grow to maturity.  (Consider building a word syllable
  32 by syllable.)  An object can move while it is growing.  Once it has
  33 been "finished" it never changes address again.  So the "top of the
  34 stack" is typically an immature growing object, while the rest of the
  35 stack is of mature, fixed size and fixed address objects.
  36
  37 These routines grab large chunks of memory, using a function you
  38 supply, called `obstack_chunk_alloc'.  On occasion, they free chunks,
  39 by calling `obstack_chunk_free'.  You must define them and declare
  40 them before using any obstack macros.
  41
  42 Each independent stack is represented by a `struct obstack'.
  43 Each of the obstack macros expects a pointer to such a structure
  44 as the first argument.
  45
  46 One motivation for this package is the problem of growing char strings
  47 in symbol tables.  Unless you are "fascist pig with a read-only mind"
  48 --Gosper's immortal quote from HAKMEM item 154, out of context--you
  49 would not like to put any arbitrary upper limit on the length of your
  50 symbols.
  51
  52 In practice this often means you will build many short symbols and a
  53 few long symbols.  At the time you are reading a symbol you don't know
  54 how long it is.  One traditional method is to read a symbol into a
  55 buffer, realloc()ating the buffer every time you try to read a symbol
  56 that is longer than the buffer.  This is beaut, but you still will
  57 want to copy the symbol from the buffer to a more permanent
  58 symbol-table entry say about half the time.
  59
  60 With obstacks, you can work differently.  Use one obstack for all symbol
  61 names.  As you read a symbol, grow the name in the obstack gradually.
  62 When the name is complete, finalize it.  Then, if the symbol exists already,
  63 free the newly read name.
  64
  65 The way we do this is to take a large chunk, allocating memory from
  66 low addresses.  When you want to build a symbol in the chunk you just
  67 add chars above the current "high water mark" in the chunk.  When you
  68 have finished adding chars, because you got to the end of the symbol,
  69 you know how long the chars are, and you can create a new object.
  70 Mostly the chars will not burst over the highest address of the chunk,
  71 because you would typically expect a chunk to be (say) 100 times as
  72 long as an average object.
  73
  74 In case that isn't clear, when we have enough chars to make up
  75 the object, THEY ARE ALREADY CONTIGUOUS IN THE CHUNK (guaranteed)
  76 so we just point to it where it lies.  No moving of chars is
  77 needed and this is the second win: potentially long strings need
  78 never be explicitly shuffled. Once an object is formed, it does not
  79 change its address during its lifetime.
  80
  81 When the chars burst over a chunk boundary, we allocate a larger
  82 chunk, and then copy the partly formed object from the end of the old
  83 chunk to the beginning of the new larger chunk.  We then carry on
  84 accreting characters to the end of the object as we normally would.
  85
  86 A special macro is provided to add a single char at a time to a
  87 growing object.  This allows the use of register variables, which
  88 break the ordinary 'growth' macro.
  89
  90 Summary:
  91         We allocate large chunks.
  92         We carve out one object at a time from the current chunk.
  93         Once carved, an object never moves.
  94         We are free to append data of any size to the currently
  95           growing object.
  96         Exactly one object is growing in an obstack at any one time.
  97         You can run one obstack per control block.
  98         You may have as many control blocks as you dare.
  99         Because of the way we do it, you can `unwind' an obstack
 100           back to a previous state. (You may remove objects much
 101           as you would with a stack.)
 102 */
 103
 104
 105 /* Don't do the contents of this file more than once.  */
 106
 107 #ifndef _OBSTACK_H
 108 #define _OBSTACK_H 1
 109
 110 #ifdef __cplusplus
 111 extern "C" {
 112 #endif
 113 \f
 114 /* We use subtraction of (char *) 0 instead of casting to int
 115    because on word-addressable machines a simple cast to int
 116    may ignore the byte-within-word field of the pointer.  */
 117
 118 #ifndef __PTR_TO_INT
 119 #define __PTR_TO_INT(P) ((P) - (char *) 0)
 120 #endif
 121
 122 #ifndef __INT_TO_PTR
 123 #define __INT_TO_PTR(P) ((P) + (char *) 0)
 124 #endif
 125
 126 /* We need the type of the resulting object.  In ANSI C it is ptrdiff_t
 127    but in traditional C it is usually long.  If we are in ANSI C and
 128    don't already have ptrdiff_t get it.  */
 129
 130 #if defined (__STDC__) && __STDC__ && ! defined (offsetof)
 131 #if defined (__GNUC__) && defined (IN_GCC)
 132 /* On Next machine, the system's stddef.h screws up if included
 133    after we have defined just ptrdiff_t, so include all of stddef.h.
 134    Otherwise, define just ptrdiff_t, which is all we need.  */
 135 #ifndef __NeXT__
 136 #define __need_ptrdiff_t
 137 #endif
 138 #endif
 139
 140 #include <stddef.h>
 141 #endif
 142
 143 #if defined (__STDC__) && __STDC__
 144 #define PTR_INT_TYPE ptrdiff_t
 145 #else
 146 #define PTR_INT_TYPE long
 147 #endif
 148
 149 #if defined (_LIBC) || defined (HAVE_STRING_H)
 150 #include <string.h>
 151 #define _obstack_memcpy(To, From, N) memcpy ((To), (From), (N))
 152 #else
 153 #ifdef memcpy
 154 #define _obstack_memcpy(To, From, N) memcpy ((To), (From), (N))
 155 #else
 156 #define _obstack_memcpy(To, From, N) bcopy ((From), (To), (N))
 157 #endif
 158 #endif
 159
 160 struct _obstack_chunk           /* Lives at front of each chunk. */
 161 {
 162   char  *limit;                 /* 1 past end of this chunk */
 163   struct _obstack_chunk *prev;  /* address of prior chunk or NULL */
 164   char  contents[4];            /* objects begin here */
 165 };
 166
 167 struct obstack          /* control current object in current chunk */
 168 {
 169   long  chunk_size;             /* preferred size to allocate chunks in */
 170   struct _obstack_chunk *chunk; /* address of current struct obstack_chunk */
 171   char  *object_base;           /* address of object we are building */
 172   char  *next_free;             /* where to add next char to current object */
 173   char  *chunk_limit;           /* address of char after current chunk */
 174   PTR_INT_TYPE temp;            /* Temporary for some macros.  */
 175   int   alignment_mask;         /* Mask of alignment for each object. */
 176 #if defined (__STDC__) && __STDC__
 177   /* These prototypes vary based on `use_extra_arg', and we use
 178      casts to the prototypeless function type in all assignments,
 179      but having prototypes here quiets -Wstrict-prototypes.  */
 180   struct _obstack_chunk *(*chunkfun) (void *, long);
 181   void (*freefun) (void *, struct _obstack_chunk *);
 182   void *extra_arg;              /* first arg for chunk alloc/dealloc funcs */
 183 #else
 184   struct _obstack_chunk *(*chunkfun) (); /* User's fcn to allocate a chunk.  */
 185   void (*freefun) ();           /* User's function to free a chunk.  */
 186   char *extra_arg;              /* first arg for chunk alloc/dealloc funcs */
 187 #endif
 188   unsigned use_extra_arg:1;     /* chunk alloc/dealloc funcs take extra arg */
 189   unsigned maybe_empty_object:1;/* There is a possibility that the current
 190                                    chunk contains a zero-length object.  This
 191                                    prevents freeing the chunk if we allocate
 192                                    a bigger chunk to replace it. */
 193   unsigned alloc_failed:1;      /* No longer used, as we now call the failed
 194                                    handler on error, but retained for binary
 195                                    compatibility.  */
 196 };
 197
 198 /* Declare the external functions we use; they are in obstack.c.  */
 199
 200 #if defined (__STDC__) && __STDC__
 201 extern void _obstack_newchunk (struct obstack *, int);
 202 extern void _obstack_free (struct obstack *, void *);
 203 extern int _obstack_begin (struct obstack *, int, int,
 204                             void *(*) (long), void (*) (void *));
 205 extern int _obstack_begin_1 (struct obstack *, int, int,
 206                              void *(*) (void *, long),
 207                              void (*) (void *, void *), void *);
 208 extern int _obstack_memory_used (struct obstack *);
 209 #else
 210 extern void _obstack_newchunk ();
 211 extern void _obstack_free ();
 212 extern int _obstack_begin ();
 213 extern int _obstack_begin_1 ();
 214 extern int _obstack_memory_used ();
 215 #endif
 216 \f
 217 #if defined (__STDC__) && __STDC__
 218
 219 /* Do the function-declarations after the structs
 220    but before defining the macros.  */
 221
 222 void obstack_init (struct obstack *obstack);
 223
 224 void * obstack_alloc (struct obstack *obstack, int size);
 225
 226 void * obstack_copy (struct obstack *obstack, void *address, int size);
 227 void * obstack_copy0 (struct obstack *obstack, void *address, int size);
 228
 229 void obstack_free (struct obstack *obstack, void *block);
 230
 231 void obstack_blank (struct obstack *obstack, int size);
 232
 233 void obstack_grow (struct obstack *obstack, void *data, int size);
 234 void obstack_grow0 (struct obstack *obstack, void *data, int size);
 235
 236 void obstack_1grow (struct obstack *obstack, int data_char);
 237 void obstack_ptr_grow (struct obstack *obstack, void *data);
 238 void obstack_int_grow (struct obstack *obstack, int data);
 239
 240 void * obstack_finish (struct obstack *obstack);
 241
 242 int obstack_object_size (struct obstack *obstack);
 243
 244 int obstack_room (struct obstack *obstack);
 245 void obstack_make_room (struct obstack *obstack, int size);
 246 void obstack_1grow_fast (struct obstack *obstack, int data_char);
 247 void obstack_ptr_grow_fast (struct obstack *obstack, void *data);
 248 void obstack_int_grow_fast (struct obstack *obstack, int data);
 249 void obstack_blank_fast (struct obstack *obstack, int size);
 250
 251 void * obstack_base (struct obstack *obstack);
 252 void * obstack_next_free (struct obstack *obstack);
 253 int obstack_alignment_mask (struct obstack *obstack);
 254 int obstack_chunk_size (struct obstack *obstack);
 255 int obstack_memory_used (struct obstack *obstack);
 256
 257 #endif /* __STDC__ */
 258
 259 /* Non-ANSI C cannot really support alternative functions for these macros,
 260    so we do not declare them.  */
 261
 262 /* Error handler called when `obstack_chunk_alloc' failed to allocate
 263    more memory.  This can be set to a user defined function.  The
 264    default action is to print a message and abort.  */
 265 #if defined (__STDC__) && __STDC__
 266 extern void (*obstack_alloc_failed_handler) (void);
 267 #else
 268 extern void (*obstack_alloc_failed_handler) ();
 269 #endif
 270
 271 /* Exit value used when `print_and_abort' is used.  */
 272 extern int obstack_exit_failure;
 273 \f
 274 /* Pointer to beginning of object being allocated or to be allocated next.
 275    Note that this might not be the final address of the object
 276    because a new chunk might be needed to hold the final size.  */
 277
 278 #define obstack_base(h) ((h)->object_base)
 279
 280 /* Size for allocating ordinary chunks.  */
 281
 282 #define obstack_chunk_size(h) ((h)->chunk_size)
 283
 284 /* Pointer to next byte not yet allocated in current chunk.  */
 285
 286 #define obstack_next_free(h)    ((h)->next_free)
 287
 288 /* Mask specifying low bits that should be clear in address of an object.  */
 289
 290 #define obstack_alignment_mask(h) ((h)->alignment_mask)
 291
 292 /* To prevent prototype warnings provide complete argument list in
 293    standard C version.  */
 294 #if defined (__STDC__) && __STDC__
 295
 296 #define obstack_init(h) \
 297   _obstack_begin ((h), 0, 0, \
 298                   (void *(*) (long)) obstack_chunk_alloc, (void (*) (void *)) obstack_chunk_free)
 299
 300 #define obstack_begin(h, size) \
 301   _obstack_begin ((h), (size), 0, \
 302                   (void *(*) (long)) obstack_chunk_alloc, (void (*) (void *)) obstack_chunk_free)
 303
 304 #define obstack_specify_allocation(h, size, alignment, chunkfun, freefun) \
 305   _obstack_begin ((h), (size), (alignment), \
 306                     (void *(*) (long)) (chunkfun), (void (*) (void *)) (freefun))
 307
 308 #define obstack_specify_allocation_with_arg(h, size, alignment, chunkfun, freefun, arg) \
 309   _obstack_begin_1 ((h), (size), (alignment), \
 310                     (void *(*) (void *, long)) (chunkfun), \
 311                     (void (*) (void *, void *)) (freefun), (arg))
 312
 313 #define obstack_chunkfun(h, newchunkfun) \
 314   ((h) -> chunkfun = (struct _obstack_chunk *(*)(void *, long)) (newchunkfun))
 315
 316 #define obstack_freefun(h, newfreefun) \
 317   ((h) -> freefun = (void (*)(void *, struct _obstack_chunk *)) (newfreefun))
 318
 319 #else
 320
 321 #define obstack_init(h) \
 322   _obstack_begin ((h), 0, 0, \
 323                   (void *(*) ()) obstack_chunk_alloc, (void (*) ()) obstack_chunk_free)
 324
 325 #define obstack_begin(h, size) \
 326   _obstack_begin ((h), (size), 0, \
 327                   (void *(*) ()) obstack_chunk_alloc, (void (*) ()) obstack_chunk_free)
 328
 329 #define obstack_specify_allocation(h, size, alignment, chunkfun, freefun) \
 330   _obstack_begin ((h), (size), (alignment), \
 331                     (void *(*) ()) (chunkfun), (void (*) ()) (freefun))
 332
 333 #define obstack_specify_allocation_with_arg(h, size, alignment, chunkfun, freefun, arg) \
 334   _obstack_begin_1 ((h), (size), (alignment), \
 335                     (void *(*) ()) (chunkfun), (void (*) ()) (freefun), (arg))
 336
 337 #define obstack_chunkfun(h, newchunkfun) \
 338   ((h) -> chunkfun = (struct _obstack_chunk *(*)()) (newchunkfun))
 339
 340 #define obstack_freefun(h, newfreefun) \
 341   ((h) -> freefun = (void (*)()) (newfreefun))
 342
 343 #endif
 344
 345 #define obstack_1grow_fast(h,achar) (*((h)->next_free)++ = achar)
 346
 347 #define obstack_blank_fast(h,n) ((h)->next_free += (n))
 348
 349 #define obstack_memory_used(h) _obstack_memory_used (h)
 350 \f
 351 #if defined (__GNUC__) && defined (__STDC__) && __STDC__
 352 /* NextStep 2.0 cc is really gcc 1.93 but it defines __GNUC__ = 2 and
 353    does not implement __extension__.  But that compiler doesn't define
 354    __GNUC_MINOR__.  */
 355 #if __GNUC__ < 2 || (__NeXT__ && !__GNUC_MINOR__)
 356 #define __extension__
 357 #endif
 358
 359 /* For GNU C, if not -traditional,
 360    we can define these macros to compute all args only once
 361    without using a global variable.
 362    Also, we can avoid using the `temp' slot, to make faster code.  */
 363
 364 #define obstack_object_size(OBSTACK)                                    \
 365   __extension__                                                         \
 366   ({ struct obstack *__o = (OBSTACK);                                   \
 367      (unsigned) (__o->next_free - __o->object_base); })
 368
 369 #define obstack_room(OBSTACK)                                           \
 370   __extension__                                                         \
 371   ({ struct obstack *__o = (OBSTACK);                                   \
 372      (unsigned) (__o->chunk_limit - __o->next_free); })
 373
 374 #define obstack_make_room(OBSTACK,length)                               \
 375 __extension__                                                           \
 376 ({ struct obstack *__o = (OBSTACK);                                     \
 377    int __len = (length);                                                \
 378    if (__o->chunk_limit - __o->next_free < __len)                       \
 379      _obstack_newchunk (__o, __len);                                    \
 380    (void) 0; })
 381
 382 #define obstack_empty_p(OBSTACK)                                        \
 383   __extension__                                                         \
 384   ({ struct obstack *__o = (OBSTACK);                                   \
 385      (__o->chunk->prev == 0 && __o->next_free - __o->chunk->contents == 0); })
 386
 387 #define obstack_grow(OBSTACK,where,length)                              \
 388 __extension__                                                           \
 389 ({ struct obstack *__o = (OBSTACK);                                     \
 390    int __len = (length);                                                \
 391    if (__o->next_free + __len > __o->chunk_limit)                       \
 392      _obstack_newchunk (__o, __len);                                    \
 393    _obstack_memcpy (__o->next_free, (char *) (where), __len);           \
 394    __o->next_free += __len;                                             \
 395    (void) 0; })
 396
 397 #define obstack_grow0(OBSTACK,where,length)                             \
 398 __extension__                                                           \
 399 ({ struct obstack *__o = (OBSTACK);                                     \
 400    int __len = (length);                                                \
 401    if (__o->next_free + __len + 1 > __o->chunk_limit)                   \
 402      _obstack_newchunk (__o, __len + 1);                                \
 403    _obstack_memcpy (__o->next_free, (char *) (where), __len);           \
 404    __o->next_free += __len;                                             \
 405    *(__o->next_free)++ = 0;                                             \
 406    (void) 0; })
 407
 408 #define obstack_1grow(OBSTACK,datum)                                    \
 409 __extension__                                                           \
 410 ({ struct obstack *__o = (OBSTACK);                                     \
 411    if (__o->next_free + 1 > __o->chunk_limit)                           \
 412      _obstack_newchunk (__o, 1);                                        \
 413    *(__o->next_free)++ = (datum);                                       \
 414    (void) 0; })
 415
 416 /* These assume that the obstack alignment is good enough for pointers or ints,
 417    and that the data added so far to the current object
 418    shares that much alignment.  */
 419
 420 #define obstack_ptr_grow(OBSTACK,datum)                                 \
 421 __extension__                                                           \
 422 ({ struct obstack *__o = (OBSTACK);                                     \
 423    if (__o->next_free + sizeof (void *) > __o->chunk_limit)             \
 424      _obstack_newchunk (__o, sizeof (void *));                          \
 425    *((void **)__o->next_free)++ = ((void *)datum);                      \
 426    (void) 0; })
 427
 428 #define obstack_int_grow(OBSTACK,datum)                                 \
 429 __extension__                                                           \
 430 ({ struct obstack *__o = (OBSTACK);                                     \
 431    if (__o->next_free + sizeof (int) > __o->chunk_limit)                \
 432      _obstack_newchunk (__o, sizeof (int));                             \
 433    *((int *)__o->next_free)++ = ((int)datum);                           \
 434    (void) 0; })
 435
 436 #define obstack_ptr_grow_fast(h,aptr) (*((void **) (h)->next_free)++ = (void *)aptr)
 437 #define obstack_int_grow_fast(h,aint) (*((int *) (h)->next_free)++ = (int) aint)
 438
 439 #define obstack_blank(OBSTACK,length)                                   \
 440 __extension__                                                           \
 441 ({ struct obstack *__o = (OBSTACK);                                     \
 442    int __len = (length);                                                \
 443    if (__o->chunk_limit - __o->next_free < __len)                       \
 444      _obstack_newchunk (__o, __len);                                    \
 445    __o->next_free += __len;                                             \
 446    (void) 0; })
 447
 448 #define obstack_alloc(OBSTACK,length)                                   \
 449 __extension__                                                           \
 450 ({ struct obstack *__h = (OBSTACK);                                     \
 451    obstack_blank (__h, (length));                                       \
 452    obstack_finish (__h); })
 453
 454 #define obstack_copy(OBSTACK,where,length)                              \
 455 __extension__                                                           \
 456 ({ struct obstack *__h = (OBSTACK);                                     \
 457    obstack_grow (__h, (where), (length));                               \
 458    obstack_finish (__h); })
 459
 460 #define obstack_copy0(OBSTACK,where,length)                             \
 461 __extension__                                                           \
 462 ({ struct obstack *__h = (OBSTACK);                                     \
 463    obstack_grow0 (__h, (where), (length));                              \
 464    obstack_finish (__h); })
 465
 466 /* The local variable is named __o1 to avoid a name conflict
 467    when obstack_blank is called.  */
 468 #define obstack_finish(OBSTACK)                                         \
 469 __extension__                                                           \
 470 ({ struct obstack *__o1 = (OBSTACK);                                    \
 471    void *value;                                                         \
 472    value = (void *) __o1->object_base;                                  \
 473    if (__o1->next_free == value)                                        \
 474      __o1->maybe_empty_object = 1;                                      \
 475    __o1->next_free                                                      \
 476      = __INT_TO_PTR ((__PTR_TO_INT (__o1->next_free)+__o1->alignment_mask)\
 477                      & ~ (__o1->alignment_mask));                       \
 478    if (__o1->next_free - (char *)__o1->chunk                            \
 479        > __o1->chunk_limit - (char *)__o1->chunk)                       \
 480      __o1->next_free = __o1->chunk_limit;                               \
 481    __o1->object_base = __o1->next_free;                                 \
 482    value; })
 483
 484 #define obstack_free(OBSTACK, OBJ)                                      \
 485 __extension__                                                           \
 486 ({ struct obstack *__o = (OBSTACK);                                     \
 487    void *__obj = (OBJ);                                                 \
 488    if (__obj > (void *)__o->chunk && __obj < (void *)__o->chunk_limit)  \
 489      __o->next_free = __o->object_base = __obj;                         \
 490    else (obstack_free) (__o, __obj); })
 491 \f
 492 #else /* not __GNUC__ or not __STDC__ */
 493
 494 #define obstack_object_size(h) \
 495  (unsigned) ((h)->next_free - (h)->object_base)
 496
 497 #define obstack_room(h)         \
 498  (unsigned) ((h)->chunk_limit - (h)->next_free)
 499
 500 #define obstack_empty_p(h) \
 501  ((h)->chunk->prev == 0 && (h)->next_free - (h)->chunk->contents == 0)
 502
 503 /* Note that the call to _obstack_newchunk is enclosed in (..., 0)
 504    so that we can avoid having void expressions
 505    in the arms of the conditional expression.
 506    Casting the third operand to void was tried before,
 507    but some compilers won't accept it.  */
 508
 509 #define obstack_make_room(h,length)                                     \
 510 ( (h)->temp = (length),                                                 \
 511   (((h)->next_free + (h)->temp > (h)->chunk_limit)                      \
 512    ? (_obstack_newchunk ((h), (h)->temp), 0) : 0))
 513
 514 #define obstack_grow(h,where,length)                                    \
 515 ( (h)->temp = (length),                                                 \
 516   (((h)->next_free + (h)->temp > (h)->chunk_limit)                      \
 517    ? (_obstack_newchunk ((h), (h)->temp), 0) : 0),                      \
 518   _obstack_memcpy ((h)->next_free, (char *) (where), (h)->temp),        \
 519   (h)->next_free += (h)->temp)
 520
 521 #define obstack_grow0(h,where,length)                                   \
 522 ( (h)->temp = (length),                                                 \
 523   (((h)->next_free + (h)->temp + 1 > (h)->chunk_limit)                  \
 524    ? (_obstack_newchunk ((h), (h)->temp + 1), 0) : 0),                  \
 525   _obstack_memcpy ((h)->next_free, (char *) (where), (h)->temp),        \
 526   (h)->next_free += (h)->temp,                                          \
 527   *((h)->next_free)++ = 0)
 528
 529 #define obstack_1grow(h,datum)                                          \
 530 ( (((h)->next_free + 1 > (h)->chunk_limit)                              \
 531    ? (_obstack_newchunk ((h), 1), 0) : 0),                              \
 532   (*((h)->next_free)++ = (datum)))
 533
 534 #define obstack_ptr_grow(h,datum)                                       \
 535 ( (((h)->next_free + sizeof (char *) > (h)->chunk_limit)                \
 536    ? (_obstack_newchunk ((h), sizeof (char *)), 0) : 0),                \
 537   (*((char **) (((h)->next_free+=sizeof(char *))-sizeof(char *))) = ((char *) datum)))
 538
 539 #define obstack_int_grow(h,datum)                                       \
 540 ( (((h)->next_free + sizeof (int) > (h)->chunk_limit)                   \
 541    ? (_obstack_newchunk ((h), sizeof (int)), 0) : 0),                   \
 542   (*((int *) (((h)->next_free+=sizeof(int))-sizeof(int))) = ((int) datum)))
 543
 544 #define obstack_ptr_grow_fast(h,aptr) (*((char **) (h)->next_free)++ = (char *) aptr)
 545 #define obstack_int_grow_fast(h,aint) (*((int *) (h)->next_free)++ = (int) aint)
 546
 547 #define obstack_blank(h,length)                                         \
 548 ( (h)->temp = (length),                                                 \
 549   (((h)->chunk_limit - (h)->next_free < (h)->temp)                      \
 550    ? (_obstack_newchunk ((h), (h)->temp), 0) : 0),                      \
 551   ((h)->next_free += (h)->temp))
 552
 553 #define obstack_alloc(h,length)                                         \
 554  (obstack_blank ((h), (length)), obstack_finish ((h)))
 555
 556 #define obstack_copy(h,where,length)                                    \
 557  (obstack_grow ((h), (where), (length)), obstack_finish ((h)))
 558
 559 #define obstack_copy0(h,where,length)                                   \
 560  (obstack_grow0 ((h), (where), (length)), obstack_finish ((h)))
 561
 562 #define obstack_finish(h)                                               \
 563 ( ((h)->next_free == (h)->object_base                                   \
 564    ? (((h)->maybe_empty_object = 1), 0)                                 \
 565    : 0),                                                                \
 566   (h)->temp = __PTR_TO_INT ((h)->object_base),                          \
 567   (h)->next_free                                                        \
 568     = __INT_TO_PTR ((__PTR_TO_INT ((h)->next_free)+(h)->alignment_mask) \
 569                     & ~ ((h)->alignment_mask)),                         \
 570   (((h)->next_free - (char *) (h)->chunk                                \
 571     > (h)->chunk_limit - (char *) (h)->chunk)                           \
 572    ? ((h)->next_free = (h)->chunk_limit) : 0),                          \
 573   (h)->object_base = (h)->next_free,                                    \
 574   __INT_TO_PTR ((h)->temp))
 575
 576 #if defined (__STDC__) && __STDC__
 577 #define obstack_free(h,obj)                                             \
 578 ( (h)->temp = (char *) (obj) - (char *) (h)->chunk,                     \
 579   (((h)->temp > 0 && (h)->temp < (h)->chunk_limit - (char *) (h)->chunk)\
 580    ? (int) ((h)->next_free = (h)->object_base                           \
 581             = (h)->temp + (char *) (h)->chunk)                          \
 582    : (((obstack_free) ((h), (h)->temp + (char *) (h)->chunk), 0), 0)))
 583 #else
 584 #define obstack_free(h,obj)                                             \
 585 ( (h)->temp = (char *) (obj) - (char *) (h)->chunk,                     \
 586   (((h)->temp > 0 && (h)->temp < (h)->chunk_limit - (char *) (h)->chunk)\
 587    ? (int) ((h)->next_free = (h)->object_base                           \
 588             = (h)->temp + (char *) (h)->chunk)                          \
 589    : (_obstack_free ((h), (h)->temp + (char *) (h)->chunk), 0)))
 590 #endif
 591
 592 #endif /* not __GNUC__ or not __STDC__ */
 593
 594 #ifdef __cplusplus
 595 }       /* C++ */
 596 #endif
 597
 598 #endif /* obstack.h */