1 /* obstack.c - subroutines used implicitly by object stack macros
2 Copyright (C) 1988, 1989, 1990, 1991, 1992, 1993, 1994, 1996, 1997, 1998,
3 1999, 2000, 2001, 2002, 2003, 2004, 2005 Free Software Foundation, Inc.
4 This file is part of the GNU C Library.
5
6 The GNU C Library is free software; you can redistribute it and/or
7 modify it under the terms of the GNU Lesser General Public
8 License as published by the Free Software Foundation; either
9 version 2.1 of the License, or (at your option) any later version.
10
11 The GNU C Library 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 GNU
14 Lesser General Public License for more details.
15
16 You should have received a copy of the GNU Lesser General Public
17 License along with the GNU C Library; if not, see
18 <http://www.gnu.org/licenses/>. */
19
20
21 #ifdef HAVE_CONFIG_H
22 # include <config.h>
23 #endif
24
25 #ifdef _LIBC
26 # include <obstack.h>
27 #ifndef __UCLIBC__
28 # include <shlib-compat.h>
29 #else
30 # define HAVE_INTTYPES_H 1
31 # define HAVE_STDINT_H 1
32 #endif
33 #else
34 # include "obstack.h"
35 #endif
36
37 /* NOTE BEFORE MODIFYING THIS FILE: This version number must be
38 incremented whenever callers compiled using an old obstack.h can no
39 longer properly call the functions in this obstack.c. */
40 #define OBSTACK_INTERFACE_VERSION 1
41
42 /* Comment out all this code if we are using the GNU C Library, and are not
43 actually compiling the library itself, and the installed library
44 supports the same library interface we do. This code is part of the GNU
45 C Library, but also included in many other GNU distributions. Compiling
46 and linking in this code is a waste when using the GNU C library
47 (especially if it is a shared library). Rather than having every GNU
48 program understand `configure --with-gnu-libc' and omit the object
49 files, it is simpler to just do this in the source for each such file. */
50
51 #include <stdio.h> /* Random thing to get __GNU_LIBRARY__. */
52 #if !defined _LIBC && defined __GNU_LIBRARY__ && __GNU_LIBRARY__ > 1
53 # include <gnu-versions.h>
54 # if _GNU_OBSTACK_INTERFACE_VERSION == OBSTACK_INTERFACE_VERSION
55 # define ELIDE_CODE
56 # endif
57 #endif
58
59 #include <stddef.h>
60
61 #ifndef ELIDE_CODE
62
63
64 # if HAVE_INTTYPES_H
65 # include <inttypes.h>
66 # endif
67 # if HAVE_STDINT_H || defined _LIBC
68 # include <stdint.h>
69 # endif
70
71 /* Determine default alignment. */
72 union fooround
73 {
74 uintmax_t i;
75 long double d;
76 void *p;
77 };
78 struct fooalign
79 {
80 char c;
81 union fooround u;
82 };
83 /* If malloc were really smart, it would round addresses to DEFAULT_ALIGNMENT.
84 But in fact it might be less smart and round addresses to as much as
85 DEFAULT_ROUNDING. So we prepare for it to do that. */
86 enum
87 {
88 DEFAULT_ALIGNMENT = offsetof (struct fooalign, u),
89 DEFAULT_ROUNDING = sizeof (union fooround)
90 };
91
92 /* When we copy a long block of data, this is the unit to do it with.
93 On some machines, copying successive ints does not work;
94 in such a case, redefine COPYING_UNIT to `long' (if that works)
95 or `char' as a last resort. */
96 # ifndef COPYING_UNIT
97 # define COPYING_UNIT int
98 # endif
99
100
101 /* The functions allocating more room by calling `obstack_chunk_alloc'
102 jump to the handler pointed to by `obstack_alloc_failed_handler'.
103 This can be set to a user defined function which should either
104 abort gracefully or use longjump - but shouldn't return. This
105 variable by default points to the internal function
106 `print_and_abort'. */
107 static void print_and_abort (void);
108 static void (*__obstack_alloc_failed_handler) (void) = print_and_abort;
109 strong_alias(__obstack_alloc_failed_handler,obstack_alloc_failed_handler)
110
111 /* Exit value used when `print_and_abort' is used. */
112 # include <stdlib.h>
113 # ifdef _LIBC
114 static int __obstack_exit_failure = EXIT_FAILURE;
strong_alias(__obstack_exit_failure,obstack_exit_failure)115 strong_alias(__obstack_exit_failure,obstack_exit_failure)
116 # else
117 # include "exitfail.h"
118 # define __obstack_exit_failure exit_failure
119 # endif
120
121 # if 0
122 # if SHLIB_COMPAT (libc, GLIBC_2_0, GLIBC_2_3_4)
123 /* A looong time ago (before 1994, anyway; we're not sure) this global variable
124 was used by non-GNU-C macros to avoid multiple evaluation. The GNU C
125 library still exports it because somebody might use it. */
126 struct obstack *_obstack_compat;
127 compat_symbol (libc, _obstack_compat, _obstack, GLIBC_2_0);
128 # endif
129 # endif
130
131 /* Define a macro that either calls functions with the traditional malloc/free
132 calling interface, or calls functions with the mmalloc/mfree interface
133 (that adds an extra first argument), based on the state of use_extra_arg.
134 For free, do not use ?:, since some compilers, like the MIPS compilers,
135 do not allow (expr) ? void : void. */
136
137 # define CALL_CHUNKFUN(h, size) \
138 (((h) -> use_extra_arg) \
139 ? (*(h)->chunkfun) ((h)->extra_arg, (size)) \
140 : (*(struct _obstack_chunk *(*) (long)) (h)->chunkfun) ((size)))
141
142 # define CALL_FREEFUN(h, old_chunk) \
143 do { \
144 if ((h) -> use_extra_arg) \
145 (*(h)->freefun) ((h)->extra_arg, (old_chunk)); \
146 else \
147 (*(void (*) (void *)) (h)->freefun) ((old_chunk)); \
148 } while (0)
149
150
151 /* Initialize an obstack H for use. Specify chunk size SIZE (0 means default).
152 Objects start on multiples of ALIGNMENT (0 means use default).
153 CHUNKFUN is the function to use to allocate chunks,
154 and FREEFUN the function to free them.
155
156 Return nonzero if successful, calls obstack_alloc_failed_handler if
157 allocation fails. */
158
159 int
160 _obstack_begin (struct obstack *h,
161 int size, int alignment,
162 void *(*chunkfun) (long),
163 void (*freefun) (void *))
164 {
165 register struct _obstack_chunk *chunk; /* points to new chunk */
166
167 if (alignment == 0)
168 alignment = DEFAULT_ALIGNMENT;
169 if (size == 0)
170 /* Default size is what GNU malloc can fit in a 4096-byte block. */
171 {
172 /* 12 is sizeof (mhead) and 4 is EXTRA from GNU malloc.
173 Use the values for range checking, because if range checking is off,
174 the extra bytes won't be missed terribly, but if range checking is on
175 and we used a larger request, a whole extra 4096 bytes would be
176 allocated.
177
178 These number are irrelevant to the new GNU malloc. I suspect it is
179 less sensitive to the size of the request. */
180 int extra = ((((12 + DEFAULT_ROUNDING - 1) & ~(DEFAULT_ROUNDING - 1))
181 + 4 + DEFAULT_ROUNDING - 1)
182 & ~(DEFAULT_ROUNDING - 1));
183 size = 4096 - extra;
184 }
185
186 h->chunkfun = (struct _obstack_chunk * (*)(void *, long)) chunkfun;
187 h->freefun = (void (*) (void *, struct _obstack_chunk *)) freefun;
188 h->chunk_size = size;
189 h->alignment_mask = alignment - 1;
190 h->use_extra_arg = 0;
191
192 chunk = h->chunk = CALL_CHUNKFUN (h, h -> chunk_size);
193 if (!chunk)
194 (*__obstack_alloc_failed_handler) ();
195 h->next_free = h->object_base = __PTR_ALIGN ((char *) chunk, chunk->contents,
196 alignment - 1);
197 h->chunk_limit = chunk->limit
198 = (char *) chunk + h->chunk_size;
199 chunk->prev = 0;
200 /* The initial chunk now contains no empty object. */
201 h->maybe_empty_object = 0;
202 h->alloc_failed = 0;
203 return 1;
204 }
205
206 int
_obstack_begin_1(struct obstack * h,int size,int alignment,void * (* chunkfun)(void *,long),void (* freefun)(void *,void *),void * arg)207 _obstack_begin_1 (struct obstack *h, int size, int alignment,
208 void *(*chunkfun) (void *, long),
209 void (*freefun) (void *, void *),
210 void *arg)
211 {
212 register struct _obstack_chunk *chunk; /* points to new chunk */
213
214 if (alignment == 0)
215 alignment = DEFAULT_ALIGNMENT;
216 if (size == 0)
217 /* Default size is what GNU malloc can fit in a 4096-byte block. */
218 {
219 /* 12 is sizeof (mhead) and 4 is EXTRA from GNU malloc.
220 Use the values for range checking, because if range checking is off,
221 the extra bytes won't be missed terribly, but if range checking is on
222 and we used a larger request, a whole extra 4096 bytes would be
223 allocated.
224
225 These number are irrelevant to the new GNU malloc. I suspect it is
226 less sensitive to the size of the request. */
227 int extra = ((((12 + DEFAULT_ROUNDING - 1) & ~(DEFAULT_ROUNDING - 1))
228 + 4 + DEFAULT_ROUNDING - 1)
229 & ~(DEFAULT_ROUNDING - 1));
230 size = 4096 - extra;
231 }
232
233 h->chunkfun = (struct _obstack_chunk * (*)(void *,long)) chunkfun;
234 h->freefun = (void (*) (void *, struct _obstack_chunk *)) freefun;
235 h->chunk_size = size;
236 h->alignment_mask = alignment - 1;
237 h->extra_arg = arg;
238 h->use_extra_arg = 1;
239
240 chunk = h->chunk = CALL_CHUNKFUN (h, h -> chunk_size);
241 if (!chunk)
242 (*__obstack_alloc_failed_handler) ();
243 h->next_free = h->object_base = __PTR_ALIGN ((char *) chunk, chunk->contents,
244 alignment - 1);
245 h->chunk_limit = chunk->limit
246 = (char *) chunk + h->chunk_size;
247 chunk->prev = 0;
248 /* The initial chunk now contains no empty object. */
249 h->maybe_empty_object = 0;
250 h->alloc_failed = 0;
251 return 1;
252 }
253
254 /* Allocate a new current chunk for the obstack *H
255 on the assumption that LENGTH bytes need to be added
256 to the current object, or a new object of length LENGTH allocated.
257 Copies any partial object from the end of the old chunk
258 to the beginning of the new one. */
259
260 void
_obstack_newchunk(struct obstack * h,int length)261 _obstack_newchunk (struct obstack *h, int length)
262 {
263 register struct _obstack_chunk *old_chunk = h->chunk;
264 register struct _obstack_chunk *new_chunk;
265 register long new_size;
266 register long obj_size = h->next_free - h->object_base;
267 register long i;
268 long already;
269 char *object_base;
270
271 /* Compute size for new chunk. */
272 new_size = (obj_size + length) + (obj_size >> 3) + h->alignment_mask + 100;
273 if (new_size < h->chunk_size)
274 new_size = h->chunk_size;
275
276 /* Allocate and initialize the new chunk. */
277 new_chunk = CALL_CHUNKFUN (h, new_size);
278 if (!new_chunk)
279 (*__obstack_alloc_failed_handler) ();
280 h->chunk = new_chunk;
281 new_chunk->prev = old_chunk;
282 new_chunk->limit = h->chunk_limit = (char *) new_chunk + new_size;
283
284 /* Compute an aligned object_base in the new chunk */
285 object_base =
286 __PTR_ALIGN ((char *) new_chunk, new_chunk->contents, h->alignment_mask);
287
288 /* Move the existing object to the new chunk.
289 Word at a time is fast and is safe if the object
290 is sufficiently aligned. */
291 if (h->alignment_mask + 1 >= DEFAULT_ALIGNMENT)
292 {
293 for (i = obj_size / sizeof (COPYING_UNIT) - 1;
294 i >= 0; i--)
295 ((COPYING_UNIT *)object_base)[i]
296 = ((COPYING_UNIT *)h->object_base)[i];
297 /* We used to copy the odd few remaining bytes as one extra COPYING_UNIT,
298 but that can cross a page boundary on a machine
299 which does not do strict alignment for COPYING_UNITS. */
300 already = obj_size / sizeof (COPYING_UNIT) * sizeof (COPYING_UNIT);
301 }
302 else
303 already = 0;
304 /* Copy remaining bytes one by one. */
305 for (i = already; i < obj_size; i++)
306 object_base[i] = h->object_base[i];
307
308 /* If the object just copied was the only data in OLD_CHUNK,
309 free that chunk and remove it from the chain.
310 But not if that chunk might contain an empty object. */
311 if (! h->maybe_empty_object
312 && (h->object_base
313 == __PTR_ALIGN ((char *) old_chunk, old_chunk->contents,
314 h->alignment_mask)))
315 {
316 new_chunk->prev = old_chunk->prev;
317 CALL_FREEFUN (h, old_chunk);
318 }
319
320 h->object_base = object_base;
321 h->next_free = h->object_base + obj_size;
322 /* The new chunk certainly contains no empty object yet. */
323 h->maybe_empty_object = 0;
324 }
325 libc_hidden_def(_obstack_newchunk)
326
327 /* Return nonzero if object OBJ has been allocated from obstack H.
328 This is here for debugging.
329 If you use it in a program, you are probably losing. */
330
331 /* Suppress -Wmissing-prototypes warning. We don't want to declare this in
332 obstack.h because it is just for debugging. */
333 int _obstack_allocated_p (struct obstack *h, void *obj);
334
335 int
_obstack_allocated_p(struct obstack * h,void * obj)336 _obstack_allocated_p (struct obstack *h, void *obj)
337 {
338 register struct _obstack_chunk *lp; /* below addr of any objects in this chunk */
339 register struct _obstack_chunk *plp; /* point to previous chunk if any */
340
341 lp = (h)->chunk;
342 /* We use >= rather than > since the object cannot be exactly at
343 the beginning of the chunk but might be an empty object exactly
344 at the end of an adjacent chunk. */
345 while (lp != 0 && ((void *) lp >= obj || (void *) (lp)->limit < obj))
346 {
347 plp = lp->prev;
348 lp = plp;
349 }
350 return lp != 0;
351 }
352
353 /* Free objects in obstack H, including OBJ and everything allocate
354 more recently than OBJ. If OBJ is zero, free everything in H. */
355
356 # undef obstack_free
357
358 void
obstack_free(struct obstack * h,void * obj)359 obstack_free (struct obstack *h, void *obj)
360 {
361 register struct _obstack_chunk *lp; /* below addr of any objects in this chunk */
362 register struct _obstack_chunk *plp; /* point to previous chunk if any */
363
364 lp = h->chunk;
365 /* We use >= because there cannot be an object at the beginning of a chunk.
366 But there can be an empty object at that address
367 at the end of another chunk. */
368 while (lp != 0 && ((void *) lp >= obj || (void *) (lp)->limit < obj))
369 {
370 plp = lp->prev;
371 CALL_FREEFUN (h, lp);
372 lp = plp;
373 /* If we switch chunks, we can't tell whether the new current
374 chunk contains an empty object, so assume that it may. */
375 h->maybe_empty_object = 1;
376 }
377 if (lp)
378 {
379 h->object_base = h->next_free = (char *) (obj);
380 h->chunk_limit = lp->limit;
381 h->chunk = lp;
382 }
383 else if (obj != 0)
384 /* obj is not in any of the chunks! */
385 abort ();
386 }
387
388 # if 0
389 /* Older versions of libc used a function _obstack_free intended to be
390 called by non-GCC compilers. */
391 strong_alias (obstack_free, _obstack_free)
392 # endif
393
394 int
_obstack_memory_used(struct obstack * h)395 _obstack_memory_used (struct obstack *h)
396 {
397 register struct _obstack_chunk* lp;
398 register int nbytes = 0;
399
400 for (lp = h->chunk; lp != 0; lp = lp->prev)
401 {
402 nbytes += lp->limit - (char *) lp;
403 }
404 return nbytes;
405 }
406
407 /* Define the error handler. */
408 # ifdef _LIBC
409 # include <libintl.h>
410 # else
411 # include "gettext.h"
412 # endif
413 # ifndef _
414 # define _(msgid) gettext (msgid)
415 # endif
416
417 # if defined _LIBC && !defined __UCLIBC__
418 # include <libio/iolibio.h>
419 # endif
420
421 # ifndef __attribute__
422 /* This feature is available in gcc versions 2.5 and later. */
423 # if __GNUC__ < 2 || (__GNUC__ == 2 && __GNUC_MINOR__ < 5)
424 # define __attribute__(Spec) /* empty */
425 # endif
426 # endif
427
428 static void
429 attribute_noreturn
print_and_abort(void)430 print_and_abort (void)
431 {
432 /* Don't change any of these strings. Yes, it would be possible to add
433 the newline to the string and use fputs or so. But this must not
434 happen because the "memory exhausted" message appears in other places
435 like this and the translation should be reused instead of creating
436 a very similar string which requires a separate translation. */
437 # if defined _LIBC && !defined __UCLIBC__
438 (void) __fxprintf (NULL, "%s\n", _("memory exhausted"));
439 # else
440 fprintf (stderr, "%s\n", _("memory exhausted"));
441 # endif
442 exit (__obstack_exit_failure);
443 }
444
445 #endif /* !ELIDE_CODE */
446