1 /* obstack.c - subroutines used implicitly by object stack macros
3 Copyright (C) 1988, 1989, 1990, 1991, 1992, 1993, 1994, 1996, 1997,
4 1998, 1999, 2000, 2001, 2002, 2003, 2004 Free Software Foundation,
7 This program is free software; you can redistribute it and/or modify
8 it under the terms of the GNU General Public License as published by
9 the Free Software Foundation; either version 2, or (at your option)
12 This program 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
15 GNU General Public License for more details.
17 You should have received a copy of the GNU General Public License along
18 with this program; if not, write to the Free Software Foundation,
19 Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. */
31 /* NOTE BEFORE MODIFYING THIS FILE: This version number must be
32 incremented whenever callers compiled using an old obstack.h can no
33 longer properly call the functions in this obstack.c. */
34 #define OBSTACK_INTERFACE_VERSION 1
36 /* Comment out all this code if we are using the GNU C Library, and are not
37 actually compiling the library itself, and the installed library
38 supports the same library interface we do. This code is part of the GNU
39 C Library, but also included in many other GNU distributions. Compiling
40 and linking in this code is a waste when using the GNU C library
41 (especially if it is a shared library). Rather than having every GNU
42 program understand `configure --with-gnu-libc' and omit the object
43 files, it is simpler to just do this in the source for each such file. */
45 #include <stdio.h> /* Random thing to get __GNU_LIBRARY__. */
46 #if !defined _LIBC && defined __GNU_LIBRARY__ && __GNU_LIBRARY__ > 1
47 # include <gnu-versions.h>
48 # if _GNU_OBSTACK_INTERFACE_VERSION == OBSTACK_INTERFACE_VERSION
53 #if defined _LIBC && defined USE_IN_LIBIO
62 /* Determine default alignment. */
69 /* If malloc were really smart, it would round addresses to DEFAULT_ALIGNMENT.
70 But in fact it might be less smart and round addresses to as much as
71 DEFAULT_ROUNDING. So we prepare for it to do that. */
74 DEFAULT_ALIGNMENT = offsetof (struct { char c; union fooround u; }, u),
75 DEFAULT_ROUNDING = sizeof (union fooround)
78 /* When we copy a long block of data, this is the unit to do it with.
79 On some machines, copying successive ints does not work;
80 in such a case, redefine COPYING_UNIT to `long' (if that works)
81 or `char' as a last resort. */
83 # define COPYING_UNIT int
87 /* The functions allocating more room by calling `obstack_chunk_alloc'
88 jump to the handler pointed to by `obstack_alloc_failed_handler'.
89 This can be set to a user defined function which should either
90 abort gracefully or use longjump - but shouldn't return. This
91 variable by default points to the internal function
93 static void print_and_abort (void);
94 void (*obstack_alloc_failed_handler) (void) = print_and_abort;
96 /* Exit value used when `print_and_abort' is used. */
99 int obstack_exit_failure = EXIT_FAILURE;
101 # include "exitfail.h"
102 # define obstack_exit_failure exit_failure
105 /* Define a macro that either calls functions with the traditional malloc/free
106 calling interface, or calls functions with the mmalloc/mfree interface
107 (that adds an extra first argument), based on the state of use_extra_arg.
108 For free, do not use ?:, since some compilers, like the MIPS compilers,
109 do not allow (expr) ? void : void. */
111 # define CALL_CHUNKFUN(h, size) \
112 (((h) -> use_extra_arg) \
113 ? (*(h)->chunkfun) ((h)->extra_arg, (size)) \
114 : (*(struct _obstack_chunk *(*) (long)) (h)->chunkfun) ((size)))
116 # define CALL_FREEFUN(h, old_chunk) \
118 if ((h) -> use_extra_arg) \
119 (*(h)->freefun) ((h)->extra_arg, (old_chunk)); \
121 (*(void (*) (void *)) (h)->freefun) ((old_chunk)); \
125 /* Initialize an obstack H for use. Specify chunk size SIZE (0 means default).
126 Objects start on multiples of ALIGNMENT (0 means use default).
127 CHUNKFUN is the function to use to allocate chunks,
128 and FREEFUN the function to free them.
130 Return nonzero if successful, calls obstack_alloc_failed_handler if
134 _obstack_begin (struct obstack *h,
135 int size, int alignment,
136 void *(*chunkfun) (long),
137 void (*freefun) (void *))
139 register struct _obstack_chunk *chunk; /* points to new chunk */
142 alignment = DEFAULT_ALIGNMENT;
144 /* Default size is what GNU malloc can fit in a 4096-byte block. */
146 /* 12 is sizeof (mhead) and 4 is EXTRA from GNU malloc.
147 Use the values for range checking, because if range checking is off,
148 the extra bytes won't be missed terribly, but if range checking is on
149 and we used a larger request, a whole extra 4096 bytes would be
152 These number are irrelevant to the new GNU malloc. I suspect it is
153 less sensitive to the size of the request. */
154 int extra = ((((12 + DEFAULT_ROUNDING - 1) & ~(DEFAULT_ROUNDING - 1))
155 + 4 + DEFAULT_ROUNDING - 1)
156 & ~(DEFAULT_ROUNDING - 1));
160 h->chunkfun = (struct _obstack_chunk * (*)(void *, long)) chunkfun;
161 h->freefun = (void (*) (void *, struct _obstack_chunk *)) freefun;
162 h->chunk_size = size;
163 h->alignment_mask = alignment - 1;
164 h->use_extra_arg = 0;
166 chunk = h->chunk = CALL_CHUNKFUN (h, h -> chunk_size);
168 (*obstack_alloc_failed_handler) ();
169 h->next_free = h->object_base = chunk->contents;
170 h->chunk_limit = chunk->limit
171 = (char *) chunk + h->chunk_size;
173 /* The initial chunk now contains no empty object. */
174 h->maybe_empty_object = 0;
180 _obstack_begin_1 (struct obstack *h, int size, int alignment,
181 void *(*chunkfun) (void *, long),
182 void (*freefun) (void *, void *),
185 register struct _obstack_chunk *chunk; /* points to new chunk */
188 alignment = DEFAULT_ALIGNMENT;
190 /* Default size is what GNU malloc can fit in a 4096-byte block. */
192 /* 12 is sizeof (mhead) and 4 is EXTRA from GNU malloc.
193 Use the values for range checking, because if range checking is off,
194 the extra bytes won't be missed terribly, but if range checking is on
195 and we used a larger request, a whole extra 4096 bytes would be
198 These number are irrelevant to the new GNU malloc. I suspect it is
199 less sensitive to the size of the request. */
200 int extra = ((((12 + DEFAULT_ROUNDING - 1) & ~(DEFAULT_ROUNDING - 1))
201 + 4 + DEFAULT_ROUNDING - 1)
202 & ~(DEFAULT_ROUNDING - 1));
206 h->chunkfun = (struct _obstack_chunk * (*)(void *,long)) chunkfun;
207 h->freefun = (void (*) (void *, struct _obstack_chunk *)) freefun;
208 h->chunk_size = size;
209 h->alignment_mask = alignment - 1;
211 h->use_extra_arg = 1;
213 chunk = h->chunk = CALL_CHUNKFUN (h, h -> chunk_size);
215 (*obstack_alloc_failed_handler) ();
216 h->next_free = h->object_base = chunk->contents;
217 h->chunk_limit = chunk->limit
218 = (char *) chunk + h->chunk_size;
220 /* The initial chunk now contains no empty object. */
221 h->maybe_empty_object = 0;
226 /* Allocate a new current chunk for the obstack *H
227 on the assumption that LENGTH bytes need to be added
228 to the current object, or a new object of length LENGTH allocated.
229 Copies any partial object from the end of the old chunk
230 to the beginning of the new one. */
233 _obstack_newchunk (struct obstack *h, int length)
235 register struct _obstack_chunk *old_chunk = h->chunk;
236 register struct _obstack_chunk *new_chunk;
237 register long new_size;
238 register long obj_size = h->next_free - h->object_base;
243 /* Compute size for new chunk. */
244 new_size = (obj_size + length) + (obj_size >> 3) + h->alignment_mask + 100;
245 if (new_size < h->chunk_size)
246 new_size = h->chunk_size;
248 /* Allocate and initialize the new chunk. */
249 new_chunk = CALL_CHUNKFUN (h, new_size);
251 (*obstack_alloc_failed_handler) ();
252 h->chunk = new_chunk;
253 new_chunk->prev = old_chunk;
254 new_chunk->limit = h->chunk_limit = (char *) new_chunk + new_size;
256 /* Compute an aligned object_base in the new chunk */
258 __PTR_ALIGN ((char *) new_chunk, new_chunk->contents, h->alignment_mask);
260 /* Move the existing object to the new chunk.
261 Word at a time is fast and is safe if the object
262 is sufficiently aligned. */
263 if (h->alignment_mask + 1 >= DEFAULT_ALIGNMENT)
265 for (i = obj_size / sizeof (COPYING_UNIT) - 1;
267 ((COPYING_UNIT *)object_base)[i]
268 = ((COPYING_UNIT *)h->object_base)[i];
269 /* We used to copy the odd few remaining bytes as one extra COPYING_UNIT,
270 but that can cross a page boundary on a machine
271 which does not do strict alignment for COPYING_UNITS. */
272 already = obj_size / sizeof (COPYING_UNIT) * sizeof (COPYING_UNIT);
276 /* Copy remaining bytes one by one. */
277 for (i = already; i < obj_size; i++)
278 object_base[i] = h->object_base[i];
280 /* If the object just copied was the only data in OLD_CHUNK,
281 free that chunk and remove it from the chain.
282 But not if that chunk might contain an empty object. */
283 if (h->object_base == old_chunk->contents && ! h->maybe_empty_object)
285 new_chunk->prev = old_chunk->prev;
286 CALL_FREEFUN (h, old_chunk);
289 h->object_base = object_base;
290 h->next_free = h->object_base + obj_size;
291 /* The new chunk certainly contains no empty object yet. */
292 h->maybe_empty_object = 0;
295 libc_hidden_def (_obstack_newchunk)
298 /* Return nonzero if object OBJ has been allocated from obstack H.
299 This is here for debugging.
300 If you use it in a program, you are probably losing. */
302 /* Suppress -Wmissing-prototypes warning. We don't want to declare this in
303 obstack.h because it is just for debugging. */
304 int _obstack_allocated_p (struct obstack *h, void *obj);
307 _obstack_allocated_p (struct obstack *h, void *obj)
309 register struct _obstack_chunk *lp; /* below addr of any objects in this chunk */
310 register struct _obstack_chunk *plp; /* point to previous chunk if any */
313 /* We use >= rather than > since the object cannot be exactly at
314 the beginning of the chunk but might be an empty object exactly
315 at the end of an adjacent chunk. */
316 while (lp != 0 && ((void *) lp >= obj || (void *) (lp)->limit < obj))
324 /* Free objects in obstack H, including OBJ and everything allocate
325 more recently than OBJ. If OBJ is zero, free everything in H. */
330 obstack_free (struct obstack *h, void *obj)
332 register struct _obstack_chunk *lp; /* below addr of any objects in this chunk */
333 register struct _obstack_chunk *plp; /* point to previous chunk if any */
336 /* We use >= because there cannot be an object at the beginning of a chunk.
337 But there can be an empty object at that address
338 at the end of another chunk. */
339 while (lp != 0 && ((void *) lp >= obj || (void *) (lp)->limit < obj))
342 CALL_FREEFUN (h, lp);
344 /* If we switch chunks, we can't tell whether the new current
345 chunk contains an empty object, so assume that it may. */
346 h->maybe_empty_object = 1;
350 h->object_base = h->next_free = (char *) (obj);
351 h->chunk_limit = lp->limit;
355 /* obj is not in any of the chunks! */
360 /* Older versions of libc used a function _obstack_free intended to be
361 called by non-GCC compilers. */
362 strong_alias (obstack_free, _obstack_free)
366 _obstack_memory_used (struct obstack *h)
368 register struct _obstack_chunk* lp;
369 register int nbytes = 0;
371 for (lp = h->chunk; lp != 0; lp = lp->prev)
373 nbytes += lp->limit - (char *) lp;
378 /* Define the error handler. */
380 # include <libintl.h>
382 # include "gettext.h"
385 # define _(msgid) gettext (msgid)
389 # include <libio/iolibio.h>
392 # ifndef __attribute__
393 /* This feature is available in gcc versions 2.5 and later. */
394 # if __GNUC__ < 2 || (__GNUC__ == 2 && __GNUC_MINOR__ < 5)
395 # define __attribute__(Spec) /* empty */
400 __attribute__ ((noreturn))
401 print_and_abort (void)
403 /* Don't change any of these strings. Yes, it would be possible to add
404 the newline to the string and use fputs or so. But this must not
405 happen because the "memory exhausted" message appears in other places
406 like this and the translation should be reused instead of creating
407 a very similar string which requires a separate translation. */
408 # if defined _LIBC && defined USE_IN_LIBIO
409 if (_IO_fwide (stderr, 0) > 0)
410 __fwprintf (stderr, L"%s\n", _("memory exhausted"));
413 fprintf (stderr, "%s\n", _("memory exhausted"));
414 exit (obstack_exit_failure);
417 #endif /* !ELIDE_CODE */