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1 /* obstack.c - subroutines used implicitly by object stack macros
2 Copyright (C) 1988-1994,96,97,98,99,2000,2001 Free Software Foundation, Inc.
3 This file is part of the GNU C Library. Its master source is NOT part of
4 the C library, however. The master source lives in /gd/gnu/lib.
5
6 The GNU C Library is free software; you can redistribute it and/or
7 modify it under the terms of the GNU Lesser General Public
8 License as published by the Free Software Foundation; either
9 version 2.1 of the License, or (at your option) any later version.
10
11 The GNU C Library is distributed in the hope that it will be useful,
12 but WITHOUT ANY WARRANTY; without even the implied warranty of
13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
14 Lesser General Public License for more details.
15
16 You should have received a copy of the GNU Lesser General Public
17 License along with the GNU C Library; if not, write to the Free
18 Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
19 02111-1307 USA. */
20
21 #ifdef HAVE_CONFIG_H
22 # include <config.h>
23 #endif
24
25 #include "obstack.h"
26
27 /* NOTE BEFORE MODIFYING THIS FILE: This version number must be
28 incremented whenever callers compiled using an old obstack.h can no
29 longer properly call the functions in this obstack.c. */
30 #define OBSTACK_INTERFACE_VERSION 1
31
32 /* Comment out all this code if we are using the GNU C Library, and are not
33 actually compiling the library itself, and the installed library
34 supports the same library interface we do. This code is part of the GNU
35 C Library, but also included in many other GNU distributions. Compiling
36 and linking in this code is a waste when using the GNU C library
37 (especially if it is a shared library). Rather than having every GNU
38 program understand `configure --with-gnu-libc' and omit the object
39 files, it is simpler to just do this in the source for each such file. */
40
41 #include <stdio.h> /* Random thing to get __GNU_LIBRARY__. */
42 #if !defined _LIBC && defined __GNU_LIBRARY__ && __GNU_LIBRARY__ > 1
43 # include <gnu-versions.h>
44 # if _GNU_OBSTACK_INTERFACE_VERSION == OBSTACK_INTERFACE_VERSION
45 # define ELIDE_CODE
46 # endif
47 #endif
48
49 #if defined _LIBC && defined USE_IN_LIBIO
50 # include <wchar.h>
51 #endif
52
53 #ifndef ELIDE_CODE
54
55
56 # if defined __STDC__ && __STDC__
57 # define POINTER void *
58 # else
59 # define POINTER char *
60 # endif
61
62 /* Determine default alignment. */
63 struct fooalign {char x; double d;};
64 # define DEFAULT_ALIGNMENT \
65 ((PTR_INT_TYPE) ((char *) &((struct fooalign *) 0)->d - (char *) 0))
66 /* If malloc were really smart, it would round addresses to DEFAULT_ALIGNMENT.
67 But in fact it might be less smart and round addresses to as much as
68 DEFAULT_ROUNDING. So we prepare for it to do that. */
69 union fooround {long x; double d;};
70 # define DEFAULT_ROUNDING (sizeof (union fooround))
71
72 /* When we copy a long block of data, this is the unit to do it with.
73 On some machines, copying successive ints does not work;
74 in such a case, redefine COPYING_UNIT to `long' (if that works)
75 or `char' as a last resort. */
76 # ifndef COPYING_UNIT
77 # define COPYING_UNIT int
78 # endif
79
80
81 /* The functions allocating more room by calling `obstack_chunk_alloc'
82 jump to the handler pointed to by `obstack_alloc_failed_handler'.
83 This can be set to a user defined function which should either
84 abort gracefully or use longjump - but shouldn't return. This
85 variable by default points to the internal function
86 `print_and_abort'. */
87 # if defined __STDC__ && __STDC__
88 static void print_and_abort (void);
89 void (*obstack_alloc_failed_handler) (void) = print_and_abort;
90 # else
91 static void print_and_abort ();
92 void (*obstack_alloc_failed_handler) () = print_and_abort;
93 # endif
94
95 /* Exit value used when `print_and_abort' is used. */
96 # if defined __GNU_LIBRARY__ || defined HAVE_STDLIB_H
97 # include <stdlib.h>
98 # endif
99 # ifndef EXIT_FAILURE
100 # define EXIT_FAILURE 1
101 # endif
102 int obstack_exit_failure = EXIT_FAILURE;
103
104 /* The non-GNU-C macros copy the obstack into this global variable
105 to avoid multiple evaluation. */
106
107 struct obstack *_obstack;
108
109 /* Define a macro that either calls functions with the traditional malloc/free
110 calling interface, or calls functions with the mmalloc/mfree interface
111 (that adds an extra first argument), based on the state of use_extra_arg.
112 For free, do not use ?:, since some compilers, like the MIPS compilers,
113 do not allow (expr) ? void : void. */
114
115 # if defined __STDC__ && __STDC__
116 # define CALL_CHUNKFUN(h, size) \
117 (((h) -> use_extra_arg) \
118 ? (*(h)->chunkfun) ((h)->extra_arg, (size)) \
119 : (*(struct _obstack_chunk *(*) (long)) (h)->chunkfun) ((size)))
120
121 # define CALL_FREEFUN(h, old_chunk) \
122 do { \
123 if ((h) -> use_extra_arg) \
124 (*(h)->freefun) ((h)->extra_arg, (old_chunk)); \
125 else \
126 (*(void (*) (void *)) (h)->freefun) ((old_chunk)); \
127 } while (0)
128 # else
129 # define CALL_CHUNKFUN(h, size) \
130 (((h) -> use_extra_arg) \
131 ? (*(h)->chunkfun) ((h)->extra_arg, (size)) \
132 : (*(struct _obstack_chunk *(*) ()) (h)->chunkfun) ((size)))
133
134 # define CALL_FREEFUN(h, old_chunk) \
135 do { \
136 if ((h) -> use_extra_arg) \
137 (*(h)->freefun) ((h)->extra_arg, (old_chunk)); \
138 else \
139 (*(void (*) ()) (h)->freefun) ((old_chunk)); \
140 } while (0)
141 # endif
142
143 \f
144 /* Initialize an obstack H for use. Specify chunk size SIZE (0 means default).
145 Objects start on multiples of ALIGNMENT (0 means use default).
146 CHUNKFUN is the function to use to allocate chunks,
147 and FREEFUN the function to free them.
148
149 Return nonzero if successful, calls obstack_alloc_failed_handler if
150 allocation fails. */
151
152 int
153 _obstack_begin (h, size, alignment, chunkfun, freefun)
154 struct obstack *h;
155 int size;
156 int alignment;
157 # if defined __STDC__ && __STDC__
158 POINTER (*chunkfun) (long);
159 void (*freefun) (void *);
160 # else
161 POINTER (*chunkfun) ();
162 void (*freefun) ();
163 # endif
164 {
165 register struct _obstack_chunk *chunk; /* points to new chunk */
166
167 if (alignment == 0)
168 alignment = (int) DEFAULT_ALIGNMENT;
169 if (size == 0)
170 /* Default size is what GNU malloc can fit in a 4096-byte block. */
171 {
172 /* 12 is sizeof (mhead) and 4 is EXTRA from GNU malloc.
173 Use the values for range checking, because if range checking is off,
174 the extra bytes won't be missed terribly, but if range checking is on
175 and we used a larger request, a whole extra 4096 bytes would be
176 allocated.
177
178 These number are irrelevant to the new GNU malloc. I suspect it is
179 less sensitive to the size of the request. */
180 int extra = ((((12 + DEFAULT_ROUNDING - 1) & ~(DEFAULT_ROUNDING - 1))
181 + 4 + DEFAULT_ROUNDING - 1)
182 & ~(DEFAULT_ROUNDING - 1));
183 size = 4096 - extra;
184 }
185
186 # if defined __STDC__ && __STDC__
187 h->chunkfun = (struct _obstack_chunk * (*)(void *, long)) chunkfun;
188 h->freefun = (void (*) (void *, struct _obstack_chunk *)) freefun;
189 # else
190 h->chunkfun = (struct _obstack_chunk * (*)()) chunkfun;
191 h->freefun = freefun;
192 # endif
193 h->chunk_size = size;
194 h->alignment_mask = alignment - 1;
195 h->use_extra_arg = 0;
196
197 chunk = h->chunk = CALL_CHUNKFUN (h, h -> chunk_size);
198 if (!chunk)
199 (*obstack_alloc_failed_handler) ();
200 h->next_free = h->object_base = chunk->contents;
201 h->chunk_limit = chunk->limit
202 = (char *) chunk + h->chunk_size;
203 chunk->prev = 0;
204 /* The initial chunk now contains no empty object. */
205 h->maybe_empty_object = 0;
206 h->alloc_failed = 0;
207 return 1;
208 }
209
210 int
211 _obstack_begin_1 (h, size, alignment, chunkfun, freefun, arg)
212 struct obstack *h;
213 int size;
214 int alignment;
215 # if defined __STDC__ && __STDC__
216 POINTER (*chunkfun) (POINTER, long);
217 void (*freefun) (POINTER, POINTER);
218 # else
219 POINTER (*chunkfun) ();
220 void (*freefun) ();
221 # endif
222 POINTER arg;
223 {
224 register struct _obstack_chunk *chunk; /* points to new chunk */
225
226 if (alignment == 0)
227 alignment = (int) DEFAULT_ALIGNMENT;
228 if (size == 0)
229 /* Default size is what GNU malloc can fit in a 4096-byte block. */
230 {
231 /* 12 is sizeof (mhead) and 4 is EXTRA from GNU malloc.
232 Use the values for range checking, because if range checking is off,
233 the extra bytes won't be missed terribly, but if range checking is on
234 and we used a larger request, a whole extra 4096 bytes would be
235 allocated.
236
237 These number are irrelevant to the new GNU malloc. I suspect it is
238 less sensitive to the size of the request. */
239 int extra = ((((12 + DEFAULT_ROUNDING - 1) & ~(DEFAULT_ROUNDING - 1))
240 + 4 + DEFAULT_ROUNDING - 1)
241 & ~(DEFAULT_ROUNDING - 1));
242 size = 4096 - extra;
243 }
244
245 # if defined __STDC__ && __STDC__
246 h->chunkfun = (struct _obstack_chunk * (*)(void *,long)) chunkfun;
247 h->freefun = (void (*) (void *, struct _obstack_chunk *)) freefun;
248 # else
249 h->chunkfun = (struct _obstack_chunk * (*)()) chunkfun;
250 h->freefun = freefun;
251 # endif
252 h->chunk_size = size;
253 h->alignment_mask = alignment - 1;
254 h->extra_arg = arg;
255 h->use_extra_arg = 1;
256
257 chunk = h->chunk = CALL_CHUNKFUN (h, h -> chunk_size);
258 if (!chunk)
259 (*obstack_alloc_failed_handler) ();
260 h->next_free = h->object_base = chunk->contents;
261 h->chunk_limit = chunk->limit
262 = (char *) chunk + h->chunk_size;
263 chunk->prev = 0;
264 /* The initial chunk now contains no empty object. */
265 h->maybe_empty_object = 0;
266 h->alloc_failed = 0;
267 return 1;
268 }
269
270 /* Allocate a new current chunk for the obstack *H
271 on the assumption that LENGTH bytes need to be added
272 to the current object, or a new object of length LENGTH allocated.
273 Copies any partial object from the end of the old chunk
274 to the beginning of the new one. */
275
276 void
277 _obstack_newchunk (h, length)
278 struct obstack *h;
279 int length;
280 {
281 register struct _obstack_chunk *old_chunk = h->chunk;
282 register struct _obstack_chunk *new_chunk;
283 register long new_size;
284 register long obj_size = h->next_free - h->object_base;
285 register long i;
286 long already;
287 char *object_base;
288
289 /* Compute size for new chunk. */
290 new_size = (obj_size + length) + (obj_size >> 3) + h->alignment_mask + 100;
291 if (new_size < h->chunk_size)
292 new_size = h->chunk_size;
293
294 /* Allocate and initialize the new chunk. */
295 new_chunk = CALL_CHUNKFUN (h, new_size);
296 if (!new_chunk)
297 (*obstack_alloc_failed_handler) ();
298 h->chunk = new_chunk;
299 new_chunk->prev = old_chunk;
300 new_chunk->limit = h->chunk_limit = (char *) new_chunk + new_size;
301
302 /* Compute an aligned object_base in the new chunk */
303 object_base =
304 __INT_TO_PTR ((__PTR_TO_INT (new_chunk->contents) + h->alignment_mask)
305 & ~ (h->alignment_mask));
306
307 /* Move the existing object to the new chunk.
308 Word at a time is fast and is safe if the object
309 is sufficiently aligned. */
310 if (h->alignment_mask + 1 >= DEFAULT_ALIGNMENT)
311 {
312 for (i = obj_size / sizeof (COPYING_UNIT) - 1;
313 i >= 0; i--)
314 ((COPYING_UNIT *)object_base)[i]
315 = ((COPYING_UNIT *)h->object_base)[i];
316 /* We used to copy the odd few remaining bytes as one extra COPYING_UNIT,
317 but that can cross a page boundary on a machine
318 which does not do strict alignment for COPYING_UNITS. */
319 already = obj_size / sizeof (COPYING_UNIT) * sizeof (COPYING_UNIT);
320 }
321 else
322 already = 0;
323 /* Copy remaining bytes one by one. */
324 for (i = already; i < obj_size; i++)
325 object_base[i] = h->object_base[i];
326
327 /* If the object just copied was the only data in OLD_CHUNK,
328 free that chunk and remove it from the chain.
329 But not if that chunk might contain an empty object. */
330 if (h->object_base == old_chunk->contents && ! h->maybe_empty_object)
331 {
332 new_chunk->prev = old_chunk->prev;
333 CALL_FREEFUN (h, old_chunk);
334 }
335
336 h->object_base = object_base;
337 h->next_free = h->object_base + obj_size;
338 /* The new chunk certainly contains no empty object yet. */
339 h->maybe_empty_object = 0;
340 }
341
342 /* Return nonzero if object OBJ has been allocated from obstack H.
343 This is here for debugging.
344 If you use it in a program, you are probably losing. */
345
346 # if defined __STDC__ && __STDC__
347 /* Suppress -Wmissing-prototypes warning. We don't want to declare this in
348 obstack.h because it is just for debugging. */
349 int _obstack_allocated_p (struct obstack *h, POINTER obj);
350 # endif
351
352 int
353 _obstack_allocated_p (h, obj)
354 struct obstack *h;
355 POINTER obj;
356 {
357 register struct _obstack_chunk *lp; /* below addr of any objects in this chunk */
358 register struct _obstack_chunk *plp; /* point to previous chunk if any */
359
360 lp = (h)->chunk;
361 /* We use >= rather than > since the object cannot be exactly at
362 the beginning of the chunk but might be an empty object exactly
363 at the end of an adjacent chunk. */
364 while (lp != 0 && ((POINTER) lp >= obj || (POINTER) (lp)->limit < obj))
365 {
366 plp = lp->prev;
367 lp = plp;
368 }
369 return lp != 0;
370 }
371 \f
372 /* Free objects in obstack H, including OBJ and everything allocate
373 more recently than OBJ. If OBJ is zero, free everything in H. */
374
375 # undef obstack_free
376
377 /* This function has two names with identical definitions.
378 This is the first one, called from non-ANSI code. */
379
380 void
381 _obstack_free (h, obj)
382 struct obstack *h;
383 POINTER obj;
384 {
385 register struct _obstack_chunk *lp; /* below addr of any objects in this chunk */
386 register struct _obstack_chunk *plp; /* point to previous chunk if any */
387
388 lp = h->chunk;
389 /* We use >= because there cannot be an object at the beginning of a chunk.
390 But there can be an empty object at that address
391 at the end of another chunk. */
392 while (lp != 0 && ((POINTER) lp >= obj || (POINTER) (lp)->limit < obj))
393 {
394 plp = lp->prev;
395 CALL_FREEFUN (h, lp);
396 lp = plp;
397 /* If we switch chunks, we can't tell whether the new current
398 chunk contains an empty object, so assume that it may. */
399 h->maybe_empty_object = 1;
400 }
401 if (lp)
402 {
403 h->object_base = h->next_free = (char *) (obj);
404 h->chunk_limit = lp->limit;
405 h->chunk = lp;
406 }
407 else if (obj != 0)
408 /* obj is not in any of the chunks! */
409 abort ();
410 }
411
412 /* This function is used from ANSI code. */
413
414 void
415 obstack_free (h, obj)
416 struct obstack *h;
417 POINTER obj;
418 {
419 register struct _obstack_chunk *lp; /* below addr of any objects in this chunk */
420 register struct _obstack_chunk *plp; /* point to previous chunk if any */
421
422 lp = h->chunk;
423 /* We use >= because there cannot be an object at the beginning of a chunk.
424 But there can be an empty object at that address
425 at the end of another chunk. */
426 while (lp != 0 && ((POINTER) lp >= obj || (POINTER) (lp)->limit < obj))
427 {
428 plp = lp->prev;
429 CALL_FREEFUN (h, lp);
430 lp = plp;
431 /* If we switch chunks, we can't tell whether the new current
432 chunk contains an empty object, so assume that it may. */
433 h->maybe_empty_object = 1;
434 }
435 if (lp)
436 {
437 h->object_base = h->next_free = (char *) (obj);
438 h->chunk_limit = lp->limit;
439 h->chunk = lp;
440 }
441 else if (obj != 0)
442 /* obj is not in any of the chunks! */
443 abort ();
444 }
445 \f
446 int
447 _obstack_memory_used (h)
448 struct obstack *h;
449 {
450 register struct _obstack_chunk* lp;
451 register int nbytes = 0;
452
453 for (lp = h->chunk; lp != 0; lp = lp->prev)
454 {
455 nbytes += lp->limit - (char *) lp;
456 }
457 return nbytes;
458 }
459 \f
460 /* Define the error handler. */
461 # ifndef _
462 # if (HAVE_LIBINTL_H && ENABLE_NLS) || defined _LIBC
463 # include <libintl.h>
464 # ifndef _
465 # define _(Str) gettext (Str)
466 # endif
467 # else
468 # define _(Str) (Str)
469 # endif
470 # endif
471 # if defined _LIBC && defined USE_IN_LIBIO
472 # include <libio/iolibio.h>
473 # define fputs(s, f) _IO_fputs (s, f)
474 # endif
475
476 # ifndef __attribute__
477 /* This feature is available in gcc versions 2.5 and later. */
478 # if __GNUC__ < 2 || (__GNUC__ == 2 && __GNUC_MINOR__ < 5)
479 # define __attribute__(Spec) /* empty */
480 # endif
481 # endif
482
483 static void
484 __attribute__ ((noreturn))
485 print_and_abort ()
486 {
487 /* Don't change any of these strings. Yes, it would be possible to add
488 the newline to the string and use fputs or so. But this must not
489 happen because the "memory exhausted" message appears in other places
490 like this and the translation should be reused instead of creating
491 a very similar string which requires a separate translation. */
492 # if defined _LIBC && defined USE_IN_LIBIO
493 if (_IO_fwide (stderr, 0) > 0)
494 __fwprintf (stderr, L"%s\n", _("memory exhausted"));
495 else
496 # endif
497 fprintf (stderr, "%s\n", _("memory exhausted"));
498 exit (obstack_exit_failure);
499 }
500 \f
501 # if 0
502 /* These are now turned off because the applications do not use it
503 and it uses bcopy via obstack_grow, which causes trouble on sysV. */
504
505 /* Now define the functional versions of the obstack macros.
506 Define them to simply use the corresponding macros to do the job. */
507
508 # if defined __STDC__ && __STDC__
509 /* These function definitions do not work with non-ANSI preprocessors;
510 they won't pass through the macro names in parentheses. */
511
512 /* The function names appear in parentheses in order to prevent
513 the macro-definitions of the names from being expanded there. */
514
515 POINTER (obstack_base) (obstack)
516 struct obstack *obstack;
517 {
518 return obstack_base (obstack);
519 }
520
521 POINTER (obstack_next_free) (obstack)
522 struct obstack *obstack;
523 {
524 return obstack_next_free (obstack);
525 }
526
527 int (obstack_object_size) (obstack)
528 struct obstack *obstack;
529 {
530 return obstack_object_size (obstack);
531 }
532
533 int (obstack_room) (obstack)
534 struct obstack *obstack;
535 {
536 return obstack_room (obstack);
537 }
538
539 int (obstack_make_room) (obstack, length)
540 struct obstack *obstack;
541 int length;
542 {
543 return obstack_make_room (obstack, length);
544 }
545
546 void (obstack_grow) (obstack, data, length)
547 struct obstack *obstack;
548 const POINTER data;
549 int length;
550 {
551 obstack_grow (obstack, data, length);
552 }
553
554 void (obstack_grow0) (obstack, data, length)
555 struct obstack *obstack;
556 const POINTER data;
557 int length;
558 {
559 obstack_grow0 (obstack, data, length);
560 }
561
562 void (obstack_1grow) (obstack, character)
563 struct obstack *obstack;
564 int character;
565 {
566 obstack_1grow (obstack, character);
567 }
568
569 void (obstack_blank) (obstack, length)
570 struct obstack *obstack;
571 int length;
572 {
573 obstack_blank (obstack, length);
574 }
575
576 void (obstack_1grow_fast) (obstack, character)
577 struct obstack *obstack;
578 int character;
579 {
580 obstack_1grow_fast (obstack, character);
581 }
582
583 void (obstack_blank_fast) (obstack, length)
584 struct obstack *obstack;
585 int length;
586 {
587 obstack_blank_fast (obstack, length);
588 }
589
590 POINTER (obstack_finish) (obstack)
591 struct obstack *obstack;
592 {
593 return obstack_finish (obstack);
594 }
595
596 POINTER (obstack_alloc) (obstack, length)
597 struct obstack *obstack;
598 int length;
599 {
600 return obstack_alloc (obstack, length);
601 }
602
603 POINTER (obstack_copy) (obstack, address, length)
604 struct obstack *obstack;
605 const POINTER address;
606 int length;
607 {
608 return obstack_copy (obstack, address, length);
609 }
610
611 POINTER (obstack_copy0) (obstack, address, length)
612 struct obstack *obstack;
613 const POINTER address;
614 int length;
615 {
616 return obstack_copy0 (obstack, address, length);
617 }
618
619 # endif /* __STDC__ */
620
621 # endif /* 0 */
622
623 #endif /* !ELIDE_CODE */