xref: /netbsd-src/external/gpl2/grep/dist/lib/obstack.c (revision 079a9ba6baf5dacd4c9d20fba9ff668bce11216e)
1 /*	$NetBSD: obstack.c,v 1.3 2018/06/14 10:14:39 kamil Exp $	*/
2 
3 /* obstack.c - subroutines used implicitly by object stack macros
4    Copyright (C) 1988-1994,96,97,98,99 Free Software Foundation, Inc.
5 
6    This file is part of the GNU C Library.  Its master source is NOT part of
7    the C library, however.  The master source lives in /gd/gnu/lib.
8 
9    The GNU C Library is free software; you can redistribute it and/or
10    modify it under the terms of the GNU Library General Public License as
11    published by the Free Software Foundation; either version 2 of the
12    License, or (at your option) any later version.
13 
14    The GNU C Library is distributed in the hope that it will be useful,
15    but WITHOUT ANY WARRANTY; without even the implied warranty of
16    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
17    Library General Public License for more details.
18 
19    You should have received a copy of the GNU Library General Public
20    License along with the GNU C Library; see the file COPYING.LIB.  If not,
21    write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
22    Boston, MA 02111-1307, USA.  */
23 
24 #ifdef HAVE_CONFIG_H
25 #include <config.h>
26 #endif
27 
28 #include "obstack.h"
29 
30 /* NOTE BEFORE MODIFYING THIS FILE: This version number must be
31    incremented whenever callers compiled using an old obstack.h can no
32    longer properly call the functions in this obstack.c.  */
33 #define OBSTACK_INTERFACE_VERSION 1
34 
35 /* Comment out all this code if we are using the GNU C Library, and are not
36    actually compiling the library itself, and the installed library
37    supports the same library interface we do.  This code is part of the GNU
38    C Library, but also included in many other GNU distributions.  Compiling
39    and linking in this code is a waste when using the GNU C library
40    (especially if it is a shared library).  Rather than having every GNU
41    program understand `configure --with-gnu-libc' and omit the object
42    files, it is simpler to just do this in the source for each such file.  */
43 
44 #include <stdio.h>		/* Random thing to get __GNU_LIBRARY__.  */
45 #if !defined (_LIBC) && defined (__GNU_LIBRARY__) && __GNU_LIBRARY__ > 1
46 #include <gnu-versions.h>
47 #if _GNU_OBSTACK_INTERFACE_VERSION == OBSTACK_INTERFACE_VERSION
48 #define ELIDE_CODE
49 #endif
50 #endif
51 
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 ((int)__alignof__(struct fooalign))
65 /* If malloc were really smart, it would round addresses to DEFAULT_ALIGNMENT.
66    But in fact it might be less smart and round addresses to as much as
67    DEFAULT_ROUNDING.  So we prepare for it to do that.  */
68 union fooround {long x; double d;};
69 #define DEFAULT_ROUNDING (sizeof (union fooround))
70 
71 /* When we copy a long block of data, this is the unit to do it with.
72    On some machines, copying successive ints does not work;
73    in such a case, redefine COPYING_UNIT to `long' (if that works)
74    or `char' as a last resort.  */
75 #ifndef COPYING_UNIT
76 #define COPYING_UNIT int
77 #endif
78 
79 
80 /* The functions allocating more room by calling `obstack_chunk_alloc'
81    jump to the handler pointed to by `obstack_alloc_failed_handler'.
82    This can be set to a user defined function which should either
83    abort gracefully or use longjump - but shouldn't return.  This
84    variable by default points to the internal function
85    `print_and_abort'.  */
86 #if defined (__STDC__) && __STDC__
87 static void print_and_abort (void);
88 void (*obstack_alloc_failed_handler) (void) = print_and_abort;
89 #else
90 static void print_and_abort ();
91 void (*obstack_alloc_failed_handler) () = print_and_abort;
92 #endif
93 
94 /* Exit value used when `print_and_abort' is used.  */
95 #if defined __GNU_LIBRARY__ || defined HAVE_STDLIB_H
96 #include <stdlib.h>
97 #endif
98 #ifndef EXIT_FAILURE
99 #define EXIT_FAILURE 1
100 #endif
101 int obstack_exit_failure = EXIT_FAILURE;
102 
103 /* The non-GNU-C macros copy the obstack into this global variable
104    to avoid multiple evaluation.  */
105 
106 struct obstack *_obstack;
107 
108 /* Define a macro that either calls functions with the traditional malloc/free
109    calling interface, or calls functions with the mmalloc/mfree interface
110    (that adds an extra first argument), based on the state of use_extra_arg.
111    For free, do not use ?:, since some compilers, like the MIPS compilers,
112    do not allow (expr) ? void : void.  */
113 
114 #if defined (__STDC__) && __STDC__
115 #define CALL_CHUNKFUN(h, size) \
116   (((h) -> use_extra_arg) \
117    ? (*(h)->chunkfun) ((h)->extra_arg, (size)) \
118    : (*(struct _obstack_chunk *(*) (long)) (h)->chunkfun) ((size)))
119 
120 #define CALL_FREEFUN(h, old_chunk) \
121   do { \
122     if ((h) -> use_extra_arg) \
123       (*(h)->freefun) ((h)->extra_arg, (old_chunk)); \
124     else \
125       (*(void (*) (void *)) (h)->freefun) ((old_chunk)); \
126   } while (0)
127 #else
128 #define CALL_CHUNKFUN(h, size) \
129   (((h) -> use_extra_arg) \
130    ? (*(h)->chunkfun) ((h)->extra_arg, (size)) \
131    : (*(struct _obstack_chunk *(*) ()) (h)->chunkfun) ((size)))
132 
133 #define CALL_FREEFUN(h, old_chunk) \
134   do { \
135     if ((h) -> use_extra_arg) \
136       (*(h)->freefun) ((h)->extra_arg, (old_chunk)); \
137     else \
138       (*(void (*) ()) (h)->freefun) ((old_chunk)); \
139   } while (0)
140 #endif
141 
142 
143 /* Initialize an obstack H for use.  Specify chunk size SIZE (0 means default).
144    Objects start on multiples of ALIGNMENT (0 means use default).
145    CHUNKFUN is the function to use to allocate chunks,
146    and FREEFUN the function to free them.
147 
148    Return nonzero if successful, calls obstack_alloc_failed_handler if
149    allocation fails.  */
150 
151 int
_obstack_begin(h,size,alignment,chunkfun,freefun)152 _obstack_begin (h, size, alignment, chunkfun, freefun)
153      struct obstack *h;
154      int size;
155      int alignment;
156 #if defined (__STDC__) && __STDC__
157      POINTER (*chunkfun) (long);
158      void (*freefun) (void *);
159 #else
160      POINTER (*chunkfun) ();
161      void (*freefun) ();
162 #endif
163 {
164   register struct _obstack_chunk *chunk; /* points to new chunk */
165 
166   if (alignment == 0)
167     alignment = (int) DEFAULT_ALIGNMENT;
168   if (size == 0)
169     /* Default size is what GNU malloc can fit in a 4096-byte block.  */
170     {
171       /* 12 is sizeof (mhead) and 4 is EXTRA from GNU malloc.
172 	 Use the values for range checking, because if range checking is off,
173 	 the extra bytes won't be missed terribly, but if range checking is on
174 	 and we used a larger request, a whole extra 4096 bytes would be
175 	 allocated.
176 
177 	 These number are irrelevant to the new GNU malloc.  I suspect it is
178 	 less sensitive to the size of the request.  */
179       int extra = ((((12 + DEFAULT_ROUNDING - 1) & ~(DEFAULT_ROUNDING - 1))
180 		    + 4 + DEFAULT_ROUNDING - 1)
181 		   & ~(DEFAULT_ROUNDING - 1));
182       size = 4096 - extra;
183     }
184 
185 #if defined (__STDC__) && __STDC__
186   h->chunkfun = (struct _obstack_chunk * (*)(void *, long)) chunkfun;
187   h->freefun = (void (*) (void *, struct _obstack_chunk *)) freefun;
188 #else
189   h->chunkfun = (struct _obstack_chunk * (*)()) chunkfun;
190   h->freefun = freefun;
191 #endif
192   h->chunk_size = size;
193   h->alignment_mask = alignment - 1;
194   h->use_extra_arg = 0;
195 
196   chunk = h->chunk = CALL_CHUNKFUN (h, h -> chunk_size);
197   if (!chunk)
198     (*obstack_alloc_failed_handler) ();
199   h->next_free = h->object_base = chunk->contents;
200   h->chunk_limit = chunk->limit
201     = (char *) chunk + h->chunk_size;
202   chunk->prev = 0;
203   /* The initial chunk now contains no empty object.  */
204   h->maybe_empty_object = 0;
205   h->alloc_failed = 0;
206   return 1;
207 }
208 
209 int
_obstack_begin_1(h,size,alignment,chunkfun,freefun,arg)210 _obstack_begin_1 (h, size, alignment, chunkfun, freefun, arg)
211      struct obstack *h;
212      int size;
213      int alignment;
214 #if defined (__STDC__) && __STDC__
215      POINTER (*chunkfun) (POINTER, long);
216      void (*freefun) (POINTER, POINTER);
217 #else
218      POINTER (*chunkfun) ();
219      void (*freefun) ();
220 #endif
221      POINTER arg;
222 {
223   register struct _obstack_chunk *chunk; /* points to new chunk */
224 
225   if (alignment == 0)
226     alignment = (int) DEFAULT_ALIGNMENT;
227   if (size == 0)
228     /* Default size is what GNU malloc can fit in a 4096-byte block.  */
229     {
230       /* 12 is sizeof (mhead) and 4 is EXTRA from GNU malloc.
231 	 Use the values for range checking, because if range checking is off,
232 	 the extra bytes won't be missed terribly, but if range checking is on
233 	 and we used a larger request, a whole extra 4096 bytes would be
234 	 allocated.
235 
236 	 These number are irrelevant to the new GNU malloc.  I suspect it is
237 	 less sensitive to the size of the request.  */
238       int extra = ((((12 + DEFAULT_ROUNDING - 1) & ~(DEFAULT_ROUNDING - 1))
239 		    + 4 + DEFAULT_ROUNDING - 1)
240 		   & ~(DEFAULT_ROUNDING - 1));
241       size = 4096 - extra;
242     }
243 
244 #if defined(__STDC__) && __STDC__
245   h->chunkfun = (struct _obstack_chunk * (*)(void *,long)) chunkfun;
246   h->freefun = (void (*) (void *, struct _obstack_chunk *)) freefun;
247 #else
248   h->chunkfun = (struct _obstack_chunk * (*)()) chunkfun;
249   h->freefun = freefun;
250 #endif
251   h->chunk_size = size;
252   h->alignment_mask = alignment - 1;
253   h->extra_arg = arg;
254   h->use_extra_arg = 1;
255 
256   chunk = h->chunk = CALL_CHUNKFUN (h, h -> chunk_size);
257   if (!chunk)
258     (*obstack_alloc_failed_handler) ();
259   h->next_free = h->object_base = chunk->contents;
260   h->chunk_limit = chunk->limit
261     = (char *) chunk + h->chunk_size;
262   chunk->prev = 0;
263   /* The initial chunk now contains no empty object.  */
264   h->maybe_empty_object = 0;
265   h->alloc_failed = 0;
266   return 1;
267 }
268 
269 /* Allocate a new current chunk for the obstack *H
270    on the assumption that LENGTH bytes need to be added
271    to the current object, or a new object of length LENGTH allocated.
272    Copies any partial object from the end of the old chunk
273    to the beginning of the new one.  */
274 
275 void
_obstack_newchunk(h,length)276 _obstack_newchunk (h, length)
277      struct obstack *h;
278      int length;
279 {
280   register struct _obstack_chunk *old_chunk = h->chunk;
281   register struct _obstack_chunk *new_chunk;
282   register long	new_size;
283   register long obj_size = h->next_free - h->object_base;
284   register long i;
285   long already;
286 
287   /* Compute size for new chunk.  */
288   new_size = (obj_size + length) + (obj_size >> 3) + 100;
289   if (new_size < h->chunk_size)
290     new_size = h->chunk_size;
291 
292   /* Allocate and initialize the new chunk.  */
293   new_chunk = CALL_CHUNKFUN (h, new_size);
294   if (!new_chunk)
295     (*obstack_alloc_failed_handler) ();
296   h->chunk = new_chunk;
297   new_chunk->prev = old_chunk;
298   new_chunk->limit = h->chunk_limit = (char *) new_chunk + new_size;
299 
300   /* Move the existing object to the new chunk.
301      Word at a time is fast and is safe if the object
302      is sufficiently aligned.  */
303   if (h->alignment_mask + 1 >= DEFAULT_ALIGNMENT)
304     {
305       for (i = obj_size / sizeof (COPYING_UNIT) - 1;
306 	   i >= 0; i--)
307 	((COPYING_UNIT *)new_chunk->contents)[i]
308 	  = ((COPYING_UNIT *)h->object_base)[i];
309       /* We used to copy the odd few remaining bytes as one extra COPYING_UNIT,
310 	 but that can cross a page boundary on a machine
311 	 which does not do strict alignment for COPYING_UNITS.  */
312       already = obj_size / sizeof (COPYING_UNIT) * sizeof (COPYING_UNIT);
313     }
314   else
315     already = 0;
316   /* Copy remaining bytes one by one.  */
317   for (i = already; i < obj_size; i++)
318     new_chunk->contents[i] = h->object_base[i];
319 
320   /* If the object just copied was the only data in OLD_CHUNK,
321      free that chunk and remove it from the chain.
322      But not if that chunk might contain an empty object.  */
323   if (h->object_base == old_chunk->contents && ! h->maybe_empty_object)
324     {
325       new_chunk->prev = old_chunk->prev;
326       CALL_FREEFUN (h, old_chunk);
327     }
328 
329   h->object_base = new_chunk->contents;
330   h->next_free = h->object_base + obj_size;
331   /* The new chunk certainly contains no empty object yet.  */
332   h->maybe_empty_object = 0;
333 }
334 
335 /* Return nonzero if object OBJ has been allocated from obstack H.
336    This is here for debugging.
337    If you use it in a program, you are probably losing.  */
338 
339 #if defined (__STDC__) && __STDC__
340 /* Suppress -Wmissing-prototypes warning.  We don't want to declare this in
341    obstack.h because it is just for debugging.  */
342 int _obstack_allocated_p (struct obstack *h, POINTER obj);
343 #endif
344 
345 int
_obstack_allocated_p(h,obj)346 _obstack_allocated_p (h, obj)
347      struct obstack *h;
348      POINTER obj;
349 {
350   register struct _obstack_chunk *lp;	/* below addr of any objects in this chunk */
351   register struct _obstack_chunk *plp;	/* point to previous chunk if any */
352 
353   lp = (h)->chunk;
354   /* We use >= rather than > since the object cannot be exactly at
355      the beginning of the chunk but might be an empty object exactly
356      at the end of an adjacent chunk.  */
357   while (lp != 0 && ((POINTER) lp >= obj || (POINTER) (lp)->limit < obj))
358     {
359       plp = lp->prev;
360       lp = plp;
361     }
362   return lp != 0;
363 }
364 
365 /* Free objects in obstack H, including OBJ and everything allocate
366    more recently than OBJ.  If OBJ is zero, free everything in H.  */
367 
368 #undef obstack_free
369 
370 /* This function has two names with identical definitions.
371    This is the first one, called from non-ANSI code.  */
372 
373 void
_obstack_free(h,obj)374 _obstack_free (h, obj)
375      struct obstack *h;
376      POINTER obj;
377 {
378   register struct _obstack_chunk *lp;	/* below addr of any objects in this chunk */
379   register struct _obstack_chunk *plp;	/* point to previous chunk if any */
380 
381   lp = h->chunk;
382   /* We use >= because there cannot be an object at the beginning of a chunk.
383      But there can be an empty object at that address
384      at the end of another chunk.  */
385   while (lp != 0 && ((POINTER) lp >= obj || (POINTER) (lp)->limit < obj))
386     {
387       plp = lp->prev;
388       CALL_FREEFUN (h, lp);
389       lp = plp;
390       /* If we switch chunks, we can't tell whether the new current
391 	 chunk contains an empty object, so assume that it may.  */
392       h->maybe_empty_object = 1;
393     }
394   if (lp)
395     {
396       h->object_base = h->next_free = (char *) (obj);
397       h->chunk_limit = lp->limit;
398       h->chunk = lp;
399     }
400   else if (obj != 0)
401     /* obj is not in any of the chunks! */
402     abort ();
403 }
404 
405 /* This function is used from ANSI code.  */
406 
407 void
obstack_free(h,obj)408 obstack_free (h, obj)
409      struct obstack *h;
410      POINTER obj;
411 {
412   register struct _obstack_chunk *lp;	/* below addr of any objects in this chunk */
413   register struct _obstack_chunk *plp;	/* point to previous chunk if any */
414 
415   lp = h->chunk;
416   /* We use >= because there cannot be an object at the beginning of a chunk.
417      But there can be an empty object at that address
418      at the end of another chunk.  */
419   while (lp != 0 && ((POINTER) lp >= obj || (POINTER) (lp)->limit < obj))
420     {
421       plp = lp->prev;
422       CALL_FREEFUN (h, lp);
423       lp = plp;
424       /* If we switch chunks, we can't tell whether the new current
425 	 chunk contains an empty object, so assume that it may.  */
426       h->maybe_empty_object = 1;
427     }
428   if (lp)
429     {
430       h->object_base = h->next_free = (char *) (obj);
431       h->chunk_limit = lp->limit;
432       h->chunk = lp;
433     }
434   else if (obj != 0)
435     /* obj is not in any of the chunks! */
436     abort ();
437 }
438 
439 int
_obstack_memory_used(h)440 _obstack_memory_used (h)
441      struct obstack *h;
442 {
443   register struct _obstack_chunk* lp;
444   register int nbytes = 0;
445 
446   for (lp = h->chunk; lp != 0; lp = lp->prev)
447     {
448       nbytes += lp->limit - (char *) lp;
449     }
450   return nbytes;
451 }
452 
453 /* Define the error handler.  */
454 #ifndef _
455 # ifdef HAVE_LIBINTL_H
456 #  include <libintl.h>
457 #  ifndef _
458 #   define _(Str) gettext (Str)
459 #  endif
460 # else
461 #  define _(Str) (Str)
462 # endif
463 #endif
464 #if defined _LIBC && defined USE_IN_LIBIO
465 # include <libio/iolibio.h>
466 # define fputs(s, f) _IO_fputs (s, f)
467 #endif
468 
469 static void
print_and_abort()470 print_and_abort ()
471 {
472   fputs (_("memory exhausted"), stderr);
473   fputc ('\n', stderr);
474   exit (obstack_exit_failure);
475 }
476 
477 #if 0
478 /* These are now turned off because the applications do not use it
479    and it uses bcopy via obstack_grow, which causes trouble on sysV.  */
480 
481 /* Now define the functional versions of the obstack macros.
482    Define them to simply use the corresponding macros to do the job.  */
483 
484 #if defined (__STDC__) && __STDC__
485 /* These function definitions do not work with non-ANSI preprocessors;
486    they won't pass through the macro names in parentheses.  */
487 
488 /* The function names appear in parentheses in order to prevent
489    the macro-definitions of the names from being expanded there.  */
490 
491 POINTER (obstack_base) (obstack)
492      struct obstack *obstack;
493 {
494   return obstack_base (obstack);
495 }
496 
497 POINTER (obstack_next_free) (obstack)
498      struct obstack *obstack;
499 {
500   return obstack_next_free (obstack);
501 }
502 
503 int (obstack_object_size) (obstack)
504      struct obstack *obstack;
505 {
506   return obstack_object_size (obstack);
507 }
508 
509 int (obstack_room) (obstack)
510      struct obstack *obstack;
511 {
512   return obstack_room (obstack);
513 }
514 
515 int (obstack_make_room) (obstack, length)
516      struct obstack *obstack;
517      int length;
518 {
519   return obstack_make_room (obstack, length);
520 }
521 
522 void (obstack_grow) (obstack, pointer, length)
523      struct obstack *obstack;
524      POINTER pointer;
525      int length;
526 {
527   obstack_grow (obstack, pointer, length);
528 }
529 
530 void (obstack_grow0) (obstack, pointer, length)
531      struct obstack *obstack;
532      POINTER pointer;
533      int length;
534 {
535   obstack_grow0 (obstack, pointer, length);
536 }
537 
538 void (obstack_1grow) (obstack, character)
539      struct obstack *obstack;
540      int character;
541 {
542   obstack_1grow (obstack, character);
543 }
544 
545 void (obstack_blank) (obstack, length)
546      struct obstack *obstack;
547      int length;
548 {
549   obstack_blank (obstack, length);
550 }
551 
552 void (obstack_1grow_fast) (obstack, character)
553      struct obstack *obstack;
554      int character;
555 {
556   obstack_1grow_fast (obstack, character);
557 }
558 
559 void (obstack_blank_fast) (obstack, length)
560      struct obstack *obstack;
561      int length;
562 {
563   obstack_blank_fast (obstack, length);
564 }
565 
566 POINTER (obstack_finish) (obstack)
567      struct obstack *obstack;
568 {
569   return obstack_finish (obstack);
570 }
571 
572 POINTER (obstack_alloc) (obstack, length)
573      struct obstack *obstack;
574      int length;
575 {
576   return obstack_alloc (obstack, length);
577 }
578 
579 POINTER (obstack_copy) (obstack, pointer, length)
580      struct obstack *obstack;
581      POINTER pointer;
582      int length;
583 {
584   return obstack_copy (obstack, pointer, length);
585 }
586 
587 POINTER (obstack_copy0) (obstack, pointer, length)
588      struct obstack *obstack;
589      POINTER pointer;
590      int length;
591 {
592   return obstack_copy0 (obstack, pointer, length);
593 }
594 
595 #endif /* __STDC__ */
596 
597 #endif /* 0 */
598 
599 #endif	/* !ELIDE_CODE */
600