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1 | /* obstack.c - subroutines used implicitly by object stack macros | |
2 | Copyright (C) 1988-2013 Free Software Foundation, Inc. | |
3 | This file is part of the GNU C Library. | |
4 | ||
5 | The GNU C Library is free software; you can redistribute it and/or | |
6 | modify it under the terms of the GNU Lesser General Public | |
7 | License as published by the Free Software Foundation; either | |
8 | version 2.1 of the License, or (at your option) any later version. | |
9 | ||
10 | The GNU C Library is distributed in the hope that it will be useful, | |
11 | but WITHOUT ANY WARRANTY; without even the implied warranty of | |
12 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU | |
13 | Lesser General Public License for more details. | |
14 | ||
15 | You should have received a copy of the GNU Lesser General Public | |
16 | License along with the GNU C Library; if not, see | |
17 | <http://www.gnu.org/licenses/>. */ | |
18 | ||
19 | ||
20 | #ifdef HAVE_CONFIG_H | |
21 | # include <config.h> | |
22 | #endif | |
23 | ||
24 | #ifdef _LIBC | |
25 | # include <obstack.h> | |
26 | # include <shlib-compat.h> | |
27 | #else | |
28 | # include "obstack.h" | |
29 | #endif | |
30 | ||
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 | |
35 | ||
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. */ | |
44 | ||
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 | |
49 | # define ELIDE_CODE | |
50 | # endif | |
51 | #endif | |
52 | ||
53 | #include <stddef.h> | |
54 | ||
55 | #ifndef ELIDE_CODE | |
56 | ||
57 | ||
58 | # if HAVE_INTTYPES_H | |
59 | # include <inttypes.h> | |
60 | # endif | |
61 | # if HAVE_STDINT_H || defined _LIBC | |
62 | # include <stdint.h> | |
63 | # endif | |
64 | ||
65 | /* Determine default alignment. */ | |
66 | union fooround | |
67 | { | |
68 | uintmax_t i; | |
69 | long double d; | |
70 | void *p; | |
71 | }; | |
72 | struct fooalign | |
73 | { | |
74 | char c; | |
75 | union fooround u; | |
76 | }; | |
77 | /* If malloc were really smart, it would round addresses to DEFAULT_ALIGNMENT. | |
78 | But in fact it might be less smart and round addresses to as much as | |
79 | DEFAULT_ROUNDING. So we prepare for it to do that. */ | |
80 | enum | |
81 | { | |
82 | DEFAULT_ALIGNMENT = offsetof (struct fooalign, u), | |
83 | DEFAULT_ROUNDING = sizeof (union fooround) | |
84 | }; | |
85 | ||
86 | /* When we copy a long block of data, this is the unit to do it with. | |
87 | On some machines, copying successive ints does not work; | |
88 | in such a case, redefine COPYING_UNIT to `long' (if that works) | |
89 | or `char' as a last resort. */ | |
90 | # ifndef COPYING_UNIT | |
91 | # define COPYING_UNIT int | |
92 | # endif | |
93 | ||
94 | ||
95 | /* The functions allocating more room by calling `obstack_chunk_alloc' | |
96 | jump to the handler pointed to by `obstack_alloc_failed_handler'. | |
97 | This can be set to a user defined function which should either | |
98 | abort gracefully or use longjump - but shouldn't return. This | |
99 | variable by default points to the internal function | |
100 | `print_and_abort'. */ | |
101 | static void print_and_abort (void); | |
102 | void (*obstack_alloc_failed_handler) (void) = print_and_abort; | |
103 | ||
104 | /* Exit value used when `print_and_abort' is used. */ | |
105 | # include <stdlib.h> | |
106 | # ifdef _LIBC | |
107 | int obstack_exit_failure = EXIT_FAILURE; | |
108 | # else | |
109 | # include "exitfail.h" | |
110 | # define obstack_exit_failure exit_failure | |
111 | # endif | |
112 | ||
113 | # ifdef _LIBC | |
114 | # if SHLIB_COMPAT (libc, GLIBC_2_0, GLIBC_2_3_4) | |
115 | /* A looong time ago (before 1994, anyway; we're not sure) this global variable | |
116 | was used by non-GNU-C macros to avoid multiple evaluation. The GNU C | |
117 | library still exports it because somebody might use it. */ | |
118 | struct obstack *_obstack_compat; | |
119 | compat_symbol (libc, _obstack_compat, _obstack, GLIBC_2_0); | |
120 | # endif | |
121 | # endif | |
122 | ||
123 | /* Define a macro that either calls functions with the traditional malloc/free | |
124 | calling interface, or calls functions with the mmalloc/mfree interface | |
125 | (that adds an extra first argument), based on the state of use_extra_arg. | |
126 | For free, do not use ?:, since some compilers, like the MIPS compilers, | |
127 | do not allow (expr) ? void : void. */ | |
128 | ||
129 | # define CALL_CHUNKFUN(h, size) \ | |
130 | (((h) -> use_extra_arg) \ | |
131 | ? (*(h)->chunkfun) ((h)->extra_arg, (size)) \ | |
132 | : (*(struct _obstack_chunk *(*) (long)) (h)->chunkfun) ((size))) | |
133 | ||
134 | # define CALL_FREEFUN(h, old_chunk) \ | |
135 | do { \ | |
136 | if ((h) -> use_extra_arg) \ | |
137 | (*(h)->freefun) ((h)->extra_arg, (old_chunk)); \ | |
138 | else \ | |
139 | (*(void (*) (void *)) (h)->freefun) ((old_chunk)); \ | |
140 | } while (0) | |
141 | ||
142 | \f | |
143 | /* Initialize an obstack H for use. Specify chunk size SIZE (0 means default). | |
144 | Objects start on multiples of ALIGNMENT (0 means use default). | |
145 | CHUNKFUN is the function to use to allocate chunks, | |
146 | and FREEFUN the function to free them. | |
147 | ||
148 | Return nonzero if successful, calls obstack_alloc_failed_handler if | |
149 | allocation fails. */ | |
150 | ||
151 | int | |
152 | _obstack_begin (struct obstack *h, | |
153 | int size, int alignment, | |
154 | void *(*chunkfun) (long), | |
155 | void (*freefun) (void *)) | |
156 | { | |
157 | register struct _obstack_chunk *chunk; /* points to new chunk */ | |
158 | ||
159 | if (alignment == 0) | |
160 | alignment = DEFAULT_ALIGNMENT; | |
161 | if (size == 0) | |
162 | /* Default size is what GNU malloc can fit in a 4096-byte block. */ | |
163 | { | |
164 | /* 12 is sizeof (mhead) and 4 is EXTRA from GNU malloc. | |
165 | Use the values for range checking, because if range checking is off, | |
166 | the extra bytes won't be missed terribly, but if range checking is on | |
167 | and we used a larger request, a whole extra 4096 bytes would be | |
168 | allocated. | |
169 | ||
170 | These number are irrelevant to the new GNU malloc. I suspect it is | |
171 | less sensitive to the size of the request. */ | |
172 | int extra = ((((12 + DEFAULT_ROUNDING - 1) & ~(DEFAULT_ROUNDING - 1)) | |
173 | + 4 + DEFAULT_ROUNDING - 1) | |
174 | & ~(DEFAULT_ROUNDING - 1)); | |
175 | size = 4096 - extra; | |
176 | } | |
177 | ||
178 | h->chunkfun = (struct _obstack_chunk * (*)(void *, long)) chunkfun; | |
179 | h->freefun = (void (*) (void *, struct _obstack_chunk *)) freefun; | |
180 | h->chunk_size = size; | |
181 | h->alignment_mask = alignment - 1; | |
182 | h->use_extra_arg = 0; | |
183 | ||
184 | chunk = h->chunk = CALL_CHUNKFUN (h, h -> chunk_size); | |
185 | if (!chunk) | |
186 | (*obstack_alloc_failed_handler) (); | |
187 | h->next_free = h->object_base = __PTR_ALIGN ((char *) chunk, chunk->contents, | |
188 | alignment - 1); | |
189 | h->chunk_limit = chunk->limit | |
190 | = (char *) chunk + h->chunk_size; | |
191 | chunk->prev = 0; | |
192 | /* The initial chunk now contains no empty object. */ | |
193 | h->maybe_empty_object = 0; | |
194 | h->alloc_failed = 0; | |
195 | return 1; | |
196 | } | |
197 | ||
198 | int | |
199 | _obstack_begin_1 (struct obstack *h, int size, int alignment, | |
200 | void *(*chunkfun) (void *, long), | |
201 | void (*freefun) (void *, void *), | |
202 | void *arg) | |
203 | { | |
204 | register struct _obstack_chunk *chunk; /* points to new chunk */ | |
205 | ||
206 | if (alignment == 0) | |
207 | alignment = DEFAULT_ALIGNMENT; | |
208 | if (size == 0) | |
209 | /* Default size is what GNU malloc can fit in a 4096-byte block. */ | |
210 | { | |
211 | /* 12 is sizeof (mhead) and 4 is EXTRA from GNU malloc. | |
212 | Use the values for range checking, because if range checking is off, | |
213 | the extra bytes won't be missed terribly, but if range checking is on | |
214 | and we used a larger request, a whole extra 4096 bytes would be | |
215 | allocated. | |
216 | ||
217 | These number are irrelevant to the new GNU malloc. I suspect it is | |
218 | less sensitive to the size of the request. */ | |
219 | int extra = ((((12 + DEFAULT_ROUNDING - 1) & ~(DEFAULT_ROUNDING - 1)) | |
220 | + 4 + DEFAULT_ROUNDING - 1) | |
221 | & ~(DEFAULT_ROUNDING - 1)); | |
222 | size = 4096 - extra; | |
223 | } | |
224 | ||
225 | h->chunkfun = (struct _obstack_chunk * (*)(void *,long)) chunkfun; | |
226 | h->freefun = (void (*) (void *, struct _obstack_chunk *)) freefun; | |
227 | h->chunk_size = size; | |
228 | h->alignment_mask = alignment - 1; | |
229 | h->extra_arg = arg; | |
230 | h->use_extra_arg = 1; | |
231 | ||
232 | chunk = h->chunk = CALL_CHUNKFUN (h, h -> chunk_size); | |
233 | if (!chunk) | |
234 | (*obstack_alloc_failed_handler) (); | |
235 | h->next_free = h->object_base = __PTR_ALIGN ((char *) chunk, chunk->contents, | |
236 | alignment - 1); | |
237 | h->chunk_limit = chunk->limit | |
238 | = (char *) chunk + h->chunk_size; | |
239 | chunk->prev = 0; | |
240 | /* The initial chunk now contains no empty object. */ | |
241 | h->maybe_empty_object = 0; | |
242 | h->alloc_failed = 0; | |
243 | return 1; | |
244 | } | |
245 | ||
246 | /* Allocate a new current chunk for the obstack *H | |
247 | on the assumption that LENGTH bytes need to be added | |
248 | to the current object, or a new object of length LENGTH allocated. | |
249 | Copies any partial object from the end of the old chunk | |
250 | to the beginning of the new one. */ | |
251 | ||
252 | void | |
253 | _obstack_newchunk (struct obstack *h, int length) | |
254 | { | |
255 | register struct _obstack_chunk *old_chunk = h->chunk; | |
256 | register struct _obstack_chunk *new_chunk; | |
257 | register long new_size; | |
258 | register long obj_size = h->next_free - h->object_base; | |
259 | register long i; | |
260 | long already; | |
261 | char *object_base; | |
262 | ||
263 | /* Compute size for new chunk. */ | |
264 | new_size = (obj_size + length) + (obj_size >> 3) + h->alignment_mask + 100; | |
265 | if (new_size < h->chunk_size) | |
266 | new_size = h->chunk_size; | |
267 | ||
268 | /* Allocate and initialize the new chunk. */ | |
269 | new_chunk = CALL_CHUNKFUN (h, new_size); | |
270 | if (!new_chunk) | |
271 | (*obstack_alloc_failed_handler) (); | |
272 | h->chunk = new_chunk; | |
273 | new_chunk->prev = old_chunk; | |
274 | new_chunk->limit = h->chunk_limit = (char *) new_chunk + new_size; | |
275 | ||
276 | /* Compute an aligned object_base in the new chunk */ | |
277 | object_base = | |
278 | __PTR_ALIGN ((char *) new_chunk, new_chunk->contents, h->alignment_mask); | |
279 | ||
280 | /* Move the existing object to the new chunk. | |
281 | Word at a time is fast and is safe if the object | |
282 | is sufficiently aligned. */ | |
283 | if (h->alignment_mask + 1 >= DEFAULT_ALIGNMENT) | |
284 | { | |
285 | for (i = obj_size / sizeof (COPYING_UNIT) - 1; | |
286 | i >= 0; i--) | |
287 | ((COPYING_UNIT *)object_base)[i] | |
288 | = ((COPYING_UNIT *)h->object_base)[i]; | |
289 | /* We used to copy the odd few remaining bytes as one extra COPYING_UNIT, | |
290 | but that can cross a page boundary on a machine | |
291 | which does not do strict alignment for COPYING_UNITS. */ | |
292 | already = obj_size / sizeof (COPYING_UNIT) * sizeof (COPYING_UNIT); | |
293 | } | |
294 | else | |
295 | already = 0; | |
296 | /* Copy remaining bytes one by one. */ | |
297 | for (i = already; i < obj_size; i++) | |
298 | object_base[i] = h->object_base[i]; | |
299 | ||
300 | /* If the object just copied was the only data in OLD_CHUNK, | |
301 | free that chunk and remove it from the chain. | |
302 | But not if that chunk might contain an empty object. */ | |
303 | if (! h->maybe_empty_object | |
304 | && (h->object_base | |
305 | == __PTR_ALIGN ((char *) old_chunk, old_chunk->contents, | |
306 | h->alignment_mask))) | |
307 | { | |
308 | new_chunk->prev = old_chunk->prev; | |
309 | CALL_FREEFUN (h, old_chunk); | |
310 | } | |
311 | ||
312 | h->object_base = object_base; | |
313 | h->next_free = h->object_base + obj_size; | |
314 | /* The new chunk certainly contains no empty object yet. */ | |
315 | h->maybe_empty_object = 0; | |
316 | } | |
317 | # ifdef _LIBC | |
318 | libc_hidden_def (_obstack_newchunk) | |
319 | # endif | |
320 | ||
321 | /* Return nonzero if object OBJ has been allocated from obstack H. | |
322 | This is here for debugging. | |
323 | If you use it in a program, you are probably losing. */ | |
324 | ||
325 | /* Suppress -Wmissing-prototypes warning. We don't want to declare this in | |
326 | obstack.h because it is just for debugging. */ | |
327 | int _obstack_allocated_p (struct obstack *h, void *obj); | |
328 | ||
329 | int | |
330 | _obstack_allocated_p (struct obstack *h, void *obj) | |
331 | { | |
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 */ | |
334 | ||
335 | lp = (h)->chunk; | |
336 | /* We use >= rather than > since the object cannot be exactly at | |
337 | the beginning of the chunk but might be an empty object exactly | |
338 | at the end of an adjacent chunk. */ | |
339 | while (lp != 0 && ((void *) lp >= obj || (void *) (lp)->limit < obj)) | |
340 | { | |
341 | plp = lp->prev; | |
342 | lp = plp; | |
343 | } | |
344 | return lp != 0; | |
345 | } | |
346 | \f | |
347 | /* Free objects in obstack H, including OBJ and everything allocate | |
348 | more recently than OBJ. If OBJ is zero, free everything in H. */ | |
349 | ||
350 | # undef obstack_free | |
351 | ||
352 | void | |
353 | obstack_free (struct obstack *h, void *obj) | |
354 | { | |
355 | register struct _obstack_chunk *lp; /* below addr of any objects in this chunk */ | |
356 | register struct _obstack_chunk *plp; /* point to previous chunk if any */ | |
357 | ||
358 | lp = h->chunk; | |
359 | /* We use >= because there cannot be an object at the beginning of a chunk. | |
360 | But there can be an empty object at that address | |
361 | at the end of another chunk. */ | |
362 | while (lp != 0 && ((void *) lp >= obj || (void *) (lp)->limit < obj)) | |
363 | { | |
364 | plp = lp->prev; | |
365 | CALL_FREEFUN (h, lp); | |
366 | lp = plp; | |
367 | /* If we switch chunks, we can't tell whether the new current | |
368 | chunk contains an empty object, so assume that it may. */ | |
369 | h->maybe_empty_object = 1; | |
370 | } | |
371 | if (lp) | |
372 | { | |
373 | h->object_base = h->next_free = (char *) (obj); | |
374 | h->chunk_limit = lp->limit; | |
375 | h->chunk = lp; | |
376 | } | |
377 | else if (obj != 0) | |
378 | /* obj is not in any of the chunks! */ | |
379 | abort (); | |
380 | } | |
381 | ||
382 | # ifdef _LIBC | |
383 | /* Older versions of libc used a function _obstack_free intended to be | |
384 | called by non-GCC compilers. */ | |
385 | strong_alias (obstack_free, _obstack_free) | |
386 | # endif | |
387 | \f | |
388 | int | |
389 | _obstack_memory_used (struct obstack *h) | |
390 | { | |
391 | register struct _obstack_chunk* lp; | |
392 | register int nbytes = 0; | |
393 | ||
394 | for (lp = h->chunk; lp != 0; lp = lp->prev) | |
395 | { | |
396 | nbytes += lp->limit - (char *) lp; | |
397 | } | |
398 | return nbytes; | |
399 | } | |
400 | \f | |
401 | /* Define the error handler. */ | |
402 | # ifdef _LIBC | |
403 | # include <libintl.h> | |
404 | # else | |
405 | # include "gettext.h" | |
406 | # endif | |
407 | # ifndef _ | |
408 | # define _(msgid) gettext (msgid) | |
409 | # endif | |
410 | ||
411 | # ifdef _LIBC | |
412 | # include <libio/iolibio.h> | |
413 | # endif | |
414 | ||
415 | # ifndef __attribute__ | |
416 | /* This feature is available in gcc versions 2.5 and later. */ | |
417 | # if __GNUC__ < 2 || (__GNUC__ == 2 && __GNUC_MINOR__ < 5) | |
418 | # define __attribute__(Spec) /* empty */ | |
419 | # endif | |
420 | # endif | |
421 | ||
422 | static void | |
423 | __attribute__ ((noreturn)) | |
424 | print_and_abort (void) | |
425 | { | |
426 | /* Don't change any of these strings. Yes, it would be possible to add | |
427 | the newline to the string and use fputs or so. But this must not | |
428 | happen because the "memory exhausted" message appears in other places | |
429 | like this and the translation should be reused instead of creating | |
430 | a very similar string which requires a separate translation. */ | |
431 | # ifdef _LIBC | |
432 | (void) __fxprintf (NULL, "%s\n", _("memory exhausted")); | |
433 | # else | |
434 | fprintf (stderr, "%s\n", _("memory exhausted")); | |
435 | # endif | |
436 | exit (obstack_exit_failure); | |
437 | } | |
438 | ||
439 | #endif /* !ELIDE_CODE */ |