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
60 /* Determine default alignment. */
61 struct 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. */
67 union fooround {long x; double d;};
68 # define DEFAULT_ROUNDING (sizeof (union fooround))
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. */
75 # define COPYING_UNIT int
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
85 static void print_and_abort (void);
86 void (*obstack_alloc_failed_handler) (void) = print_and_abort;
88 /* Exit value used when `print_and_abort' is used. */
91 int obstack_exit_failure = EXIT_FAILURE;
93 # include "exitfail.h"
94 # define obstack_exit_failure exit_failure
97 /* The non-GNU-C macros copy the obstack into this global variable
98 to avoid multiple evaluation. */
100 struct obstack *_obstack;
102 /* Define a macro that either calls functions with the traditional malloc/free
103 calling interface, or calls functions with the mmalloc/mfree interface
104 (that adds an extra first argument), based on the state of use_extra_arg.
105 For free, do not use ?:, since some compilers, like the MIPS compilers,
106 do not allow (expr) ? void : void. */
108 # define CALL_CHUNKFUN(h, size) \
109 (((h) -> use_extra_arg) \
110 ? (*(h)->chunkfun) ((h)->extra_arg, (size)) \
111 : (*(struct _obstack_chunk *(*) (long)) (h)->chunkfun) ((size)))
113 # define CALL_FREEFUN(h, old_chunk) \
115 if ((h) -> use_extra_arg) \
116 (*(h)->freefun) ((h)->extra_arg, (old_chunk)); \
118 (*(void (*) (void *)) (h)->freefun) ((old_chunk)); \
122 /* Initialize an obstack H for use. Specify chunk size SIZE (0 means default).
123 Objects start on multiples of ALIGNMENT (0 means use default).
124 CHUNKFUN is the function to use to allocate chunks,
125 and FREEFUN the function to free them.
127 Return nonzero if successful, calls obstack_alloc_failed_handler if
131 _obstack_begin (struct obstack *h,
132 int size, int alignment,
133 void *(*chunkfun) (long),
134 void (*freefun) (void *))
136 register struct _obstack_chunk *chunk; /* points to new chunk */
139 alignment = (int) DEFAULT_ALIGNMENT;
141 /* Default size is what GNU malloc can fit in a 4096-byte block. */
143 /* 12 is sizeof (mhead) and 4 is EXTRA from GNU malloc.
144 Use the values for range checking, because if range checking is off,
145 the extra bytes won't be missed terribly, but if range checking is on
146 and we used a larger request, a whole extra 4096 bytes would be
149 These number are irrelevant to the new GNU malloc. I suspect it is
150 less sensitive to the size of the request. */
151 int extra = ((((12 + DEFAULT_ROUNDING - 1) & ~(DEFAULT_ROUNDING - 1))
152 + 4 + DEFAULT_ROUNDING - 1)
153 & ~(DEFAULT_ROUNDING - 1));
157 h->chunkfun = (struct _obstack_chunk * (*)(void *, long)) chunkfun;
158 h->freefun = (void (*) (void *, struct _obstack_chunk *)) freefun;
159 h->chunk_size = size;
160 h->alignment_mask = alignment - 1;
161 h->use_extra_arg = 0;
163 chunk = h->chunk = CALL_CHUNKFUN (h, h -> chunk_size);
165 (*obstack_alloc_failed_handler) ();
166 h->next_free = h->object_base = chunk->contents;
167 h->chunk_limit = chunk->limit
168 = (char *) chunk + h->chunk_size;
170 /* The initial chunk now contains no empty object. */
171 h->maybe_empty_object = 0;
177 _obstack_begin_1 (struct obstack *h, int size, int alignment,
178 void *(*chunkfun) (void *, long),
179 void (*freefun) (void *, void *),
182 register struct _obstack_chunk *chunk; /* points to new chunk */
185 alignment = (int) DEFAULT_ALIGNMENT;
187 /* Default size is what GNU malloc can fit in a 4096-byte block. */
189 /* 12 is sizeof (mhead) and 4 is EXTRA from GNU malloc.
190 Use the values for range checking, because if range checking is off,
191 the extra bytes won't be missed terribly, but if range checking is on
192 and we used a larger request, a whole extra 4096 bytes would be
195 These number are irrelevant to the new GNU malloc. I suspect it is
196 less sensitive to the size of the request. */
197 int extra = ((((12 + DEFAULT_ROUNDING - 1) & ~(DEFAULT_ROUNDING - 1))
198 + 4 + DEFAULT_ROUNDING - 1)
199 & ~(DEFAULT_ROUNDING - 1));
203 h->chunkfun = (struct _obstack_chunk * (*)(void *,long)) chunkfun;
204 h->freefun = (void (*) (void *, struct _obstack_chunk *)) freefun;
205 h->chunk_size = size;
206 h->alignment_mask = alignment - 1;
208 h->use_extra_arg = 1;
210 chunk = h->chunk = CALL_CHUNKFUN (h, h -> chunk_size);
212 (*obstack_alloc_failed_handler) ();
213 h->next_free = h->object_base = chunk->contents;
214 h->chunk_limit = chunk->limit
215 = (char *) chunk + h->chunk_size;
217 /* The initial chunk now contains no empty object. */
218 h->maybe_empty_object = 0;
223 /* Allocate a new current chunk for the obstack *H
224 on the assumption that LENGTH bytes need to be added
225 to the current object, or a new object of length LENGTH allocated.
226 Copies any partial object from the end of the old chunk
227 to the beginning of the new one. */
230 _obstack_newchunk (struct obstack *h, int length)
232 register struct _obstack_chunk *old_chunk = h->chunk;
233 register struct _obstack_chunk *new_chunk;
234 register long new_size;
235 register long obj_size = h->next_free - h->object_base;
240 /* Compute size for new chunk. */
241 new_size = (obj_size + length) + (obj_size >> 3) + h->alignment_mask + 100;
242 if (new_size < h->chunk_size)
243 new_size = h->chunk_size;
245 /* Allocate and initialize the new chunk. */
246 new_chunk = CALL_CHUNKFUN (h, new_size);
248 (*obstack_alloc_failed_handler) ();
249 h->chunk = new_chunk;
250 new_chunk->prev = old_chunk;
251 new_chunk->limit = h->chunk_limit = (char *) new_chunk + new_size;
253 /* Compute an aligned object_base in the new chunk */
255 __INT_TO_PTR ((__PTR_TO_INT (new_chunk->contents) + h->alignment_mask)
256 & ~ (h->alignment_mask));
258 /* Move the existing object to the new chunk.
259 Word at a time is fast and is safe if the object
260 is sufficiently aligned. */
261 if (h->alignment_mask + 1 >= DEFAULT_ALIGNMENT)
263 for (i = obj_size / sizeof (COPYING_UNIT) - 1;
265 ((COPYING_UNIT *)object_base)[i]
266 = ((COPYING_UNIT *)h->object_base)[i];
267 /* We used to copy the odd few remaining bytes as one extra COPYING_UNIT,
268 but that can cross a page boundary on a machine
269 which does not do strict alignment for COPYING_UNITS. */
270 already = obj_size / sizeof (COPYING_UNIT) * sizeof (COPYING_UNIT);
274 /* Copy remaining bytes one by one. */
275 for (i = already; i < obj_size; i++)
276 object_base[i] = h->object_base[i];
278 /* If the object just copied was the only data in OLD_CHUNK,
279 free that chunk and remove it from the chain.
280 But not if that chunk might contain an empty object. */
281 if (h->object_base == old_chunk->contents && ! h->maybe_empty_object)
283 new_chunk->prev = old_chunk->prev;
284 CALL_FREEFUN (h, old_chunk);
287 h->object_base = object_base;
288 h->next_free = h->object_base + obj_size;
289 /* The new chunk certainly contains no empty object yet. */
290 h->maybe_empty_object = 0;
293 libc_hidden_def (_obstack_newchunk)
296 /* Return nonzero if object OBJ has been allocated from obstack H.
297 This is here for debugging.
298 If you use it in a program, you are probably losing. */
300 /* Suppress -Wmissing-prototypes warning. We don't want to declare this in
301 obstack.h because it is just for debugging. */
302 int _obstack_allocated_p (struct obstack *h, void *obj);
305 _obstack_allocated_p (struct obstack *h, void *obj)
307 register struct _obstack_chunk *lp; /* below addr of any objects in this chunk */
308 register struct _obstack_chunk *plp; /* point to previous chunk if any */
311 /* We use >= rather than > since the object cannot be exactly at
312 the beginning of the chunk but might be an empty object exactly
313 at the end of an adjacent chunk. */
314 while (lp != 0 && ((void *) lp >= obj || (void *) (lp)->limit < obj))
322 /* Free objects in obstack H, including OBJ and everything allocate
323 more recently than OBJ. If OBJ is zero, free everything in H. */
328 obstack_free (struct obstack *h, void *obj)
330 register struct _obstack_chunk *lp; /* below addr of any objects in this chunk */
331 register struct _obstack_chunk *plp; /* point to previous chunk if any */
334 /* We use >= because there cannot be an object at the beginning of a chunk.
335 But there can be an empty object at that address
336 at the end of another chunk. */
337 while (lp != 0 && ((void *) lp >= obj || (void *) (lp)->limit < obj))
340 CALL_FREEFUN (h, lp);
342 /* If we switch chunks, we can't tell whether the new current
343 chunk contains an empty object, so assume that it may. */
344 h->maybe_empty_object = 1;
348 h->object_base = h->next_free = (char *) (obj);
349 h->chunk_limit = lp->limit;
353 /* obj is not in any of the chunks! */
358 /* Older versions of libc used a function _obstack_free intended to be
359 called by non-GCC compilers. */
360 strong_alias (obstack_free, _obstack_free)
364 _obstack_memory_used (struct obstack *h)
366 register struct _obstack_chunk* lp;
367 register int nbytes = 0;
369 for (lp = h->chunk; lp != 0; lp = lp->prev)
371 nbytes += lp->limit - (char *) lp;
376 /* Define the error handler. */
378 # include <libintl.h>
380 # include "gettext.h"
383 # define _(msgid) gettext (msgid)
387 # include <libio/iolibio.h>
390 # ifndef __attribute__
391 /* This feature is available in gcc versions 2.5 and later. */
392 # if __GNUC__ < 2 || (__GNUC__ == 2 && __GNUC_MINOR__ < 5)
393 # define __attribute__(Spec) /* empty */
398 __attribute__ ((noreturn))
399 print_and_abort (void)
401 /* Don't change any of these strings. Yes, it would be possible to add
402 the newline to the string and use fputs or so. But this must not
403 happen because the "memory exhausted" message appears in other places
404 like this and the translation should be reused instead of creating
405 a very similar string which requires a separate translation. */
406 # if defined _LIBC && defined USE_IN_LIBIO
407 if (_IO_fwide (stderr, 0) > 0)
408 __fwprintf (stderr, L"%s\n", _("memory exhausted"));
411 fprintf (stderr, "%s\n", _("memory exhausted"));
412 exit (obstack_exit_failure);
415 #endif /* !ELIDE_CODE */