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 Free Software Foundation, Inc.
6 This program is free software; you can redistribute it and/or modify
7 it under the terms of the GNU General Public License as published by
8 the Free Software Foundation; either version 2, or (at your option)
11 This program 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
14 GNU General Public License for more details.
16 You should have received a copy of the GNU General Public License along
17 with this program; if not, write to the Free Software Foundation,
18 Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. */
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
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. */
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
52 #if defined _LIBC && defined USE_IN_LIBIO
59 /* Determine default alignment. */
60 struct fooalign {char x; double d;};
61 # define DEFAULT_ALIGNMENT \
62 ((PTR_INT_TYPE) ((char *) &((struct fooalign *) 0)->d - (char *) 0))
63 /* If malloc were really smart, it would round addresses to DEFAULT_ALIGNMENT.
64 But in fact it might be less smart and round addresses to as much as
65 DEFAULT_ROUNDING. So we prepare for it to do that. */
66 union fooround {long x; double d;};
67 # define DEFAULT_ROUNDING (sizeof (union fooround))
69 /* When we copy a long block of data, this is the unit to do it with.
70 On some machines, copying successive ints does not work;
71 in such a case, redefine COPYING_UNIT to `long' (if that works)
72 or `char' as a last resort. */
74 # define COPYING_UNIT int
78 /* The functions allocating more room by calling `obstack_chunk_alloc'
79 jump to the handler pointed to by `obstack_alloc_failed_handler'.
80 This can be set to a user defined function which should either
81 abort gracefully or use longjump - but shouldn't return. This
82 variable by default points to the internal function
84 static void print_and_abort (void);
85 void (*obstack_alloc_failed_handler) (void) = print_and_abort;
87 /* Exit value used when `print_and_abort' is used. */
92 int obstack_exit_failure = EXIT_FAILURE;
94 /* The non-GNU-C macros copy the obstack into this global variable
95 to avoid multiple evaluation. */
97 struct obstack *_obstack;
99 /* Define a macro that either calls functions with the traditional malloc/free
100 calling interface, or calls functions with the mmalloc/mfree interface
101 (that adds an extra first argument), based on the state of use_extra_arg.
102 For free, do not use ?:, since some compilers, like the MIPS compilers,
103 do not allow (expr) ? void : void. */
105 # define CALL_CHUNKFUN(h, size) \
106 (((h) -> use_extra_arg) \
107 ? (*(h)->chunkfun) ((h)->extra_arg, (size)) \
108 : (*(struct _obstack_chunk *(*) (long)) (h)->chunkfun) ((size)))
110 # define CALL_FREEFUN(h, old_chunk) \
112 if ((h) -> use_extra_arg) \
113 (*(h)->freefun) ((h)->extra_arg, (old_chunk)); \
115 (*(void (*) (void *)) (h)->freefun) ((old_chunk)); \
119 /* Initialize an obstack H for use. Specify chunk size SIZE (0 means default).
120 Objects start on multiples of ALIGNMENT (0 means use default).
121 CHUNKFUN is the function to use to allocate chunks,
122 and FREEFUN the function to free them.
124 Return nonzero if successful, calls obstack_alloc_failed_handler if
128 _obstack_begin (struct obstack *h,
129 int size, int alignment,
130 void *(*chunkfun) (long),
131 void (*freefun) (void *))
133 register struct _obstack_chunk *chunk; /* points to new chunk */
136 alignment = (int) DEFAULT_ALIGNMENT;
138 /* Default size is what GNU malloc can fit in a 4096-byte block. */
140 /* 12 is sizeof (mhead) and 4 is EXTRA from GNU malloc.
141 Use the values for range checking, because if range checking is off,
142 the extra bytes won't be missed terribly, but if range checking is on
143 and we used a larger request, a whole extra 4096 bytes would be
146 These number are irrelevant to the new GNU malloc. I suspect it is
147 less sensitive to the size of the request. */
148 int extra = ((((12 + DEFAULT_ROUNDING - 1) & ~(DEFAULT_ROUNDING - 1))
149 + 4 + DEFAULT_ROUNDING - 1)
150 & ~(DEFAULT_ROUNDING - 1));
154 h->chunkfun = (struct _obstack_chunk * (*)(void *, long)) chunkfun;
155 h->freefun = (void (*) (void *, struct _obstack_chunk *)) freefun;
156 h->chunk_size = size;
157 h->alignment_mask = alignment - 1;
158 h->use_extra_arg = 0;
160 chunk = h->chunk = CALL_CHUNKFUN (h, h -> chunk_size);
162 (*obstack_alloc_failed_handler) ();
163 h->next_free = h->object_base = chunk->contents;
164 h->chunk_limit = chunk->limit
165 = (char *) chunk + h->chunk_size;
167 /* The initial chunk now contains no empty object. */
168 h->maybe_empty_object = 0;
174 _obstack_begin_1 (struct obstack *h, int size, int alignment,
175 void *(*chunkfun) (void *, long),
176 void (*freefun) (void *, void *),
179 register struct _obstack_chunk *chunk; /* points to new chunk */
182 alignment = (int) DEFAULT_ALIGNMENT;
184 /* Default size is what GNU malloc can fit in a 4096-byte block. */
186 /* 12 is sizeof (mhead) and 4 is EXTRA from GNU malloc.
187 Use the values for range checking, because if range checking is off,
188 the extra bytes won't be missed terribly, but if range checking is on
189 and we used a larger request, a whole extra 4096 bytes would be
192 These number are irrelevant to the new GNU malloc. I suspect it is
193 less sensitive to the size of the request. */
194 int extra = ((((12 + DEFAULT_ROUNDING - 1) & ~(DEFAULT_ROUNDING - 1))
195 + 4 + DEFAULT_ROUNDING - 1)
196 & ~(DEFAULT_ROUNDING - 1));
200 h->chunkfun = (struct _obstack_chunk * (*)(void *,long)) chunkfun;
201 h->freefun = (void (*) (void *, struct _obstack_chunk *)) freefun;
202 h->chunk_size = size;
203 h->alignment_mask = alignment - 1;
205 h->use_extra_arg = 1;
207 chunk = h->chunk = CALL_CHUNKFUN (h, h -> chunk_size);
209 (*obstack_alloc_failed_handler) ();
210 h->next_free = h->object_base = chunk->contents;
211 h->chunk_limit = chunk->limit
212 = (char *) chunk + h->chunk_size;
214 /* The initial chunk now contains no empty object. */
215 h->maybe_empty_object = 0;
220 /* Allocate a new current chunk for the obstack *H
221 on the assumption that LENGTH bytes need to be added
222 to the current object, or a new object of length LENGTH allocated.
223 Copies any partial object from the end of the old chunk
224 to the beginning of the new one. */
227 _obstack_newchunk (struct obstack *h, int length)
229 register struct _obstack_chunk *old_chunk = h->chunk;
230 register struct _obstack_chunk *new_chunk;
231 register long new_size;
232 register long obj_size = h->next_free - h->object_base;
237 /* Compute size for new chunk. */
238 new_size = (obj_size + length) + (obj_size >> 3) + h->alignment_mask + 100;
239 if (new_size < h->chunk_size)
240 new_size = h->chunk_size;
242 /* Allocate and initialize the new chunk. */
243 new_chunk = CALL_CHUNKFUN (h, new_size);
245 (*obstack_alloc_failed_handler) ();
246 h->chunk = new_chunk;
247 new_chunk->prev = old_chunk;
248 new_chunk->limit = h->chunk_limit = (char *) new_chunk + new_size;
250 /* Compute an aligned object_base in the new chunk */
252 __INT_TO_PTR ((__PTR_TO_INT (new_chunk->contents) + h->alignment_mask)
253 & ~ (h->alignment_mask));
255 /* Move the existing object to the new chunk.
256 Word at a time is fast and is safe if the object
257 is sufficiently aligned. */
258 if (h->alignment_mask + 1 >= DEFAULT_ALIGNMENT)
260 for (i = obj_size / sizeof (COPYING_UNIT) - 1;
262 ((COPYING_UNIT *)object_base)[i]
263 = ((COPYING_UNIT *)h->object_base)[i];
264 /* We used to copy the odd few remaining bytes as one extra COPYING_UNIT,
265 but that can cross a page boundary on a machine
266 which does not do strict alignment for COPYING_UNITS. */
267 already = obj_size / sizeof (COPYING_UNIT) * sizeof (COPYING_UNIT);
271 /* Copy remaining bytes one by one. */
272 for (i = already; i < obj_size; i++)
273 object_base[i] = h->object_base[i];
275 /* If the object just copied was the only data in OLD_CHUNK,
276 free that chunk and remove it from the chain.
277 But not if that chunk might contain an empty object. */
278 if (h->object_base == old_chunk->contents && ! h->maybe_empty_object)
280 new_chunk->prev = old_chunk->prev;
281 CALL_FREEFUN (h, old_chunk);
284 h->object_base = object_base;
285 h->next_free = h->object_base + obj_size;
286 /* The new chunk certainly contains no empty object yet. */
287 h->maybe_empty_object = 0;
290 libc_hidden_def (_obstack_newchunk)
293 /* Return nonzero if object OBJ has been allocated from obstack H.
294 This is here for debugging.
295 If you use it in a program, you are probably losing. */
297 /* Suppress -Wmissing-prototypes warning. We don't want to declare this in
298 obstack.h because it is just for debugging. */
299 int _obstack_allocated_p (struct obstack *h, void *obj);
302 _obstack_allocated_p (struct obstack *h, void *obj)
304 register struct _obstack_chunk *lp; /* below addr of any objects in this chunk */
305 register struct _obstack_chunk *plp; /* point to previous chunk if any */
308 /* We use >= rather than > since the object cannot be exactly at
309 the beginning of the chunk but might be an empty object exactly
310 at the end of an adjacent chunk. */
311 while (lp != 0 && ((void *) lp >= obj || (void *) (lp)->limit < obj))
319 /* Free objects in obstack H, including OBJ and everything allocate
320 more recently than OBJ. If OBJ is zero, free everything in H. */
325 obstack_free (struct obstack *h, void *obj)
327 register struct _obstack_chunk *lp; /* below addr of any objects in this chunk */
328 register struct _obstack_chunk *plp; /* point to previous chunk if any */
331 /* We use >= because there cannot be an object at the beginning of a chunk.
332 But there can be an empty object at that address
333 at the end of another chunk. */
334 while (lp != 0 && ((void *) lp >= obj || (void *) (lp)->limit < obj))
337 CALL_FREEFUN (h, lp);
339 /* If we switch chunks, we can't tell whether the new current
340 chunk contains an empty object, so assume that it may. */
341 h->maybe_empty_object = 1;
345 h->object_base = h->next_free = (char *) (obj);
346 h->chunk_limit = lp->limit;
350 /* obj is not in any of the chunks! */
355 /* Older versions of libc used a function _obstack_free intended to be
356 called by non-GCC compilers. */
357 strong_alias (obstack_free, _obstack_free)
361 _obstack_memory_used (struct obstack *h)
363 register struct _obstack_chunk* lp;
364 register int nbytes = 0;
366 for (lp = h->chunk; lp != 0; lp = lp->prev)
368 nbytes += lp->limit - (char *) lp;
373 /* Define the error handler. */
375 # include <libintl.h>
377 # include "gettext.h"
379 # define _(msgid) gettext (msgid)
382 # include <libio/iolibio.h>
385 # ifndef __attribute__
386 /* This feature is available in gcc versions 2.5 and later. */
387 # if __GNUC__ < 2 || (__GNUC__ == 2 && __GNUC_MINOR__ < 5)
388 # define __attribute__(Spec) /* empty */
393 __attribute__ ((noreturn))
394 print_and_abort (void)
396 /* Don't change any of these strings. Yes, it would be possible to add
397 the newline to the string and use fputs or so. But this must not
398 happen because the "memory exhausted" message appears in other places
399 like this and the translation should be reused instead of creating
400 a very similar string which requires a separate translation. */
401 # if defined _LIBC && defined USE_IN_LIBIO
402 if (_IO_fwide (stderr, 0) > 0)
403 __fwprintf (stderr, L"%s\n", _("memory exhausted"));
406 fprintf (stderr, "%s\n", _("memory exhausted"));
407 exit (obstack_exit_failure);
410 #endif /* !ELIDE_CODE */