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