source: trunk/third/gcc/obstack.c @ 11288

Revision 11288, 17.5 KB checked in by ghudson, 26 years ago (diff)
This commit was generated by cvs2svn to compensate for changes in r11287, which included commits to RCS files with non-trunk default branches.
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1/* obstack.c - subroutines used implicitly by object stack macros
2   Copyright (C) 1988,89,90,91,92,93,94,96,97 Free Software Foundation, Inc.
3
4   the C library, however.  The master source lives in /gd/gnu/lib.
5
6   NOTE: The canonical source of this file is maintained with the GNU C Library.
7   Bugs can be reported to bug-glibc@prep.ai.mit.edu.
8
9   This program is free software; you can redistribute it and/or modify it
10   under the terms of the GNU General Public License as published by the
11   Free Software Foundation; either version 2, or (at your option) any
12   later version.
13
14   This program 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
17   GNU General Public License for more details.
18
19   You should have received a copy of the GNU General Public License
20   along with this program; if not, write to the Free Software
21   Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307,
22   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.  */
63struct 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.  */
69union 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 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, zero if out of memory.
148   To recover from an out of memory error,
149   free up some memory, then call this again.  */
150
151int
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
209int
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
275void
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.  */
342int _obstack_allocated_p (struct obstack *h, POINTER obj);
343#endif
344
345int
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
373void
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
407void
408obstack_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
439int
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
465static void
466print_and_abort ()
467{
468  fputs (_("memory exhausted\n"), stderr);
469  exit (obstack_exit_failure);
470}
471
472#if 0
473/* These are now turned off because the applications do not use it
474   and it uses bcopy via obstack_grow, which causes trouble on sysV.  */
475
476/* Now define the functional versions of the obstack macros.
477   Define them to simply use the corresponding macros to do the job.  */
478
479#if defined (__STDC__) && __STDC__
480/* These function definitions do not work with non-ANSI preprocessors;
481   they won't pass through the macro names in parentheses.  */
482
483/* The function names appear in parentheses in order to prevent
484   the macro-definitions of the names from being expanded there.  */
485
486POINTER (obstack_base) (obstack)
487     struct obstack *obstack;
488{
489  return obstack_base (obstack);
490}
491
492POINTER (obstack_next_free) (obstack)
493     struct obstack *obstack;
494{
495  return obstack_next_free (obstack);
496}
497
498int (obstack_object_size) (obstack)
499     struct obstack *obstack;
500{
501  return obstack_object_size (obstack);
502}
503
504int (obstack_room) (obstack)
505     struct obstack *obstack;
506{
507  return obstack_room (obstack);
508}
509
510int (obstack_make_room) (obstack, length)
511     struct obstack *obstack;
512     int length;
513{
514  return obstack_make_room (obstack, length);
515}
516
517void (obstack_grow) (obstack, pointer, length)
518     struct obstack *obstack;
519     POINTER pointer;
520     int length;
521{
522  obstack_grow (obstack, pointer, length);
523}
524
525void (obstack_grow0) (obstack, pointer, length)
526     struct obstack *obstack;
527     POINTER pointer;
528     int length;
529{
530  obstack_grow0 (obstack, pointer, length);
531}
532
533void (obstack_1grow) (obstack, character)
534     struct obstack *obstack;
535     int character;
536{
537  obstack_1grow (obstack, character);
538}
539
540void (obstack_blank) (obstack, length)
541     struct obstack *obstack;
542     int length;
543{
544  obstack_blank (obstack, length);
545}
546
547void (obstack_1grow_fast) (obstack, character)
548     struct obstack *obstack;
549     int character;
550{
551  obstack_1grow_fast (obstack, character);
552}
553
554void (obstack_blank_fast) (obstack, length)
555     struct obstack *obstack;
556     int length;
557{
558  obstack_blank_fast (obstack, length);
559}
560
561POINTER (obstack_finish) (obstack)
562     struct obstack *obstack;
563{
564  return obstack_finish (obstack);
565}
566
567POINTER (obstack_alloc) (obstack, length)
568     struct obstack *obstack;
569     int length;
570{
571  return obstack_alloc (obstack, length);
572}
573
574POINTER (obstack_copy) (obstack, pointer, length)
575     struct obstack *obstack;
576     POINTER pointer;
577     int length;
578{
579  return obstack_copy (obstack, pointer, length);
580}
581
582POINTER (obstack_copy0) (obstack, pointer, length)
583     struct obstack *obstack;
584     POINTER pointer;
585     int length;
586{
587  return obstack_copy0 (obstack, pointer, length);
588}
589
590#endif /* __STDC__ */
591
592#endif /* 0 */
593
594#endif  /* !ELIDE_CODE */
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