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1 | /* obstack.h - object stack macros |
2 | Copyright (C) 1988-1994,1996-1999,2003,2004,2005,2009,2011,2012 | |
3 | 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 | /* Summary: | |
21 | ||
22 | All the apparent functions defined here are macros. The idea | |
23 | is that you would use these pre-tested macros to solve a | |
24 | very specific set of problems, and they would run fast. | |
25 | Caution: no side-effects in arguments please!! They may be | |
26 | evaluated MANY times!! | |
27 | ||
28 | These macros operate a stack of objects. Each object starts life | |
29 | small, and may grow to maturity. (Consider building a word syllable | |
30 | by syllable.) An object can move while it is growing. Once it has | |
31 | been "finished" it never changes address again. So the "top of the | |
32 | stack" is typically an immature growing object, while the rest of the | |
33 | stack is of mature, fixed size and fixed address objects. | |
34 | ||
35 | These routines grab large chunks of memory, using a function you | |
36 | supply, called `obstack_chunk_alloc'. On occasion, they free chunks, | |
37 | by calling `obstack_chunk_free'. You must define them and declare | |
38 | them before using any obstack macros. | |
39 | ||
40 | Each independent stack is represented by a `struct obstack'. | |
41 | Each of the obstack macros expects a pointer to such a structure | |
42 | as the first argument. | |
43 | ||
44 | One motivation for this package is the problem of growing char strings | |
45 | in symbol tables. Unless you are "fascist pig with a read-only mind" | |
46 | --Gosper's immortal quote from HAKMEM item 154, out of context--you | |
47 | would not like to put any arbitrary upper limit on the length of your | |
48 | symbols. | |
49 | ||
50 | In practice this often means you will build many short symbols and a | |
51 | few long symbols. At the time you are reading a symbol you don't know | |
52 | how long it is. One traditional method is to read a symbol into a | |
53 | buffer, realloc()ating the buffer every time you try to read a symbol | |
54 | that is longer than the buffer. This is beaut, but you still will | |
55 | want to copy the symbol from the buffer to a more permanent | |
56 | symbol-table entry say about half the time. | |
57 | ||
58 | With obstacks, you can work differently. Use one obstack for all symbol | |
59 | names. As you read a symbol, grow the name in the obstack gradually. | |
60 | When the name is complete, finalize it. Then, if the symbol exists already, | |
61 | free the newly read name. | |
62 | ||
63 | The way we do this is to take a large chunk, allocating memory from | |
64 | low addresses. When you want to build a symbol in the chunk you just | |
65 | add chars above the current "high water mark" in the chunk. When you | |
66 | have finished adding chars, because you got to the end of the symbol, | |
67 | you know how long the chars are, and you can create a new object. | |
68 | Mostly the chars will not burst over the highest address of the chunk, | |
69 | because you would typically expect a chunk to be (say) 100 times as | |
70 | long as an average object. | |
71 | ||
72 | In case that isn't clear, when we have enough chars to make up | |
73 | the object, THEY ARE ALREADY CONTIGUOUS IN THE CHUNK (guaranteed) | |
74 | so we just point to it where it lies. No moving of chars is | |
75 | needed and this is the second win: potentially long strings need | |
76 | never be explicitly shuffled. Once an object is formed, it does not | |
77 | change its address during its lifetime. | |
78 | ||
79 | When the chars burst over a chunk boundary, we allocate a larger | |
80 | chunk, and then copy the partly formed object from the end of the old | |
81 | chunk to the beginning of the new larger chunk. We then carry on | |
82 | accreting characters to the end of the object as we normally would. | |
83 | ||
84 | A special macro is provided to add a single char at a time to a | |
85 | growing object. This allows the use of register variables, which | |
86 | break the ordinary 'growth' macro. | |
87 | ||
88 | Summary: | |
89 | We allocate large chunks. | |
90 | We carve out one object at a time from the current chunk. | |
91 | Once carved, an object never moves. | |
92 | We are free to append data of any size to the currently | |
93 | growing object. | |
94 | Exactly one object is growing in an obstack at any one time. | |
95 | You can run one obstack per control block. | |
96 | You may have as many control blocks as you dare. | |
97 | Because of the way we do it, you can `unwind' an obstack | |
98 | back to a previous state. (You may remove objects much | |
99 | as you would with a stack.) | |
100 | */ | |
101 | ||
102 | ||
103 | /* Don't do the contents of this file more than once. */ | |
104 | ||
105 | #ifndef _OBSTACK_H | |
106 | #define _OBSTACK_H 1 | |
107 | ||
108 | #ifdef __cplusplus | |
109 | extern "C" { | |
110 | #endif | |
111 | \f | |
112 | /* We need the type of a pointer subtraction. If __PTRDIFF_TYPE__ is | |
113 | defined, as with GNU C, use that; that way we don't pollute the | |
114 | namespace with <stddef.h>'s symbols. Otherwise, include <stddef.h> | |
115 | and use ptrdiff_t. */ | |
116 | ||
117 | #ifdef __PTRDIFF_TYPE__ | |
118 | # define PTR_INT_TYPE __PTRDIFF_TYPE__ | |
119 | #else | |
120 | # include <stddef.h> | |
121 | # define PTR_INT_TYPE ptrdiff_t | |
122 | #endif | |
123 | ||
124 | /* If B is the base of an object addressed by P, return the result of | |
125 | aligning P to the next multiple of A + 1. B and P must be of type | |
126 | char *. A + 1 must be a power of 2. */ | |
127 | ||
128 | #define __BPTR_ALIGN(B, P, A) ((B) + (((P) - (B) + (A)) & ~(A))) | |
129 | ||
130 | /* Similiar to _BPTR_ALIGN (B, P, A), except optimize the common case | |
131 | where pointers can be converted to integers, aligned as integers, | |
132 | and converted back again. If PTR_INT_TYPE is narrower than a | |
133 | pointer (e.g., the AS/400), play it safe and compute the alignment | |
134 | relative to B. Otherwise, use the faster strategy of computing the | |
135 | alignment relative to 0. */ | |
136 | ||
137 | #define __PTR_ALIGN(B, P, A) \ | |
138 | __BPTR_ALIGN (sizeof (PTR_INT_TYPE) < sizeof (void *) ? (B) : (char *) 0, \ | |
139 | P, A) | |
140 | ||
141 | #include <string.h> | |
142 | ||
143 | struct _obstack_chunk /* Lives at front of each chunk. */ | |
144 | { | |
145 | char *limit; /* 1 past end of this chunk */ | |
146 | struct _obstack_chunk *prev; /* address of prior chunk or NULL */ | |
147 | char contents[4]; /* objects begin here */ | |
148 | }; | |
149 | ||
150 | struct obstack /* control current object in current chunk */ | |
151 | { | |
152 | long chunk_size; /* preferred size to allocate chunks in */ | |
153 | struct _obstack_chunk *chunk; /* address of current struct obstack_chunk */ | |
154 | char *object_base; /* address of object we are building */ | |
155 | char *next_free; /* where to add next char to current object */ | |
156 | char *chunk_limit; /* address of char after current chunk */ | |
157 | union | |
158 | { | |
159 | PTR_INT_TYPE tempint; | |
160 | void *tempptr; | |
161 | } temp; /* Temporary for some macros. */ | |
162 | int alignment_mask; /* Mask of alignment for each object. */ | |
163 | /* These prototypes vary based on `use_extra_arg', and we use | |
164 | casts to the prototypeless function type in all assignments, | |
165 | but having prototypes here quiets -Wstrict-prototypes. */ | |
166 | struct _obstack_chunk *(*chunkfun) (void *, long); | |
167 | void (*freefun) (void *, struct _obstack_chunk *); | |
168 | void *extra_arg; /* first arg for chunk alloc/dealloc funcs */ | |
169 | unsigned use_extra_arg:1; /* chunk alloc/dealloc funcs take extra arg */ | |
170 | unsigned maybe_empty_object:1;/* There is a possibility that the current | |
171 | chunk contains a zero-length object. This | |
172 | prevents freeing the chunk if we allocate | |
173 | a bigger chunk to replace it. */ | |
174 | unsigned alloc_failed:1; /* No longer used, as we now call the failed | |
175 | handler on error, but retained for binary | |
176 | compatibility. */ | |
177 | }; | |
178 | ||
179 | static void _obstack_newchunk (struct obstack *h, int length); | |
180 | ||
181 | /* Exit value used when `print_and_abort' is used. */ | |
182 | extern int obstack_exit_failure; | |
183 | \f | |
184 | /* Pointer to beginning of object being allocated or to be allocated next. | |
185 | Note that this might not be the final address of the object | |
186 | because a new chunk might be needed to hold the final size. */ | |
187 | ||
188 | #define obstack_base(h) ((void *) (h)->object_base) | |
189 | ||
190 | /* Size for allocating ordinary chunks. */ | |
191 | ||
192 | #define obstack_chunk_size(h) ((h)->chunk_size) | |
193 | ||
194 | /* Pointer to next byte not yet allocated in current chunk. */ | |
195 | ||
196 | #define obstack_next_free(h) ((h)->next_free) | |
197 | ||
198 | /* Mask specifying low bits that should be clear in address of an object. */ | |
199 | ||
200 | #define obstack_alignment_mask(h) ((h)->alignment_mask) | |
201 | ||
202 | /* To prevent prototype warnings provide complete argument list. */ | |
203 | #define obstack_init(h) \ | |
204 | _obstack_begin ((h), 0, 0, \ | |
205 | (void *(*) (long)) obstack_chunk_alloc, \ | |
206 | (void (*) (void *)) obstack_chunk_free) | |
207 | ||
208 | #define obstack_begin(h, size) \ | |
209 | _obstack_begin ((h), (size), 0, \ | |
210 | (void *(*) (long)) obstack_chunk_alloc, \ | |
211 | (void (*) (void *)) obstack_chunk_free) | |
212 | ||
213 | #define obstack_specify_allocation(h, size, alignment, chunkfun, freefun) \ | |
214 | _obstack_begin ((h), (size), (alignment), \ | |
215 | (void *(*) (long)) (chunkfun), \ | |
216 | (void (*) (void *)) (freefun)) | |
217 | ||
218 | #define obstack_specify_allocation_with_arg(h, size, alignment, chunkfun, freefun, arg) \ | |
219 | _obstack_begin_1 ((h), (size), (alignment), \ | |
220 | (void *(*) (void *, long)) (chunkfun), \ | |
221 | (void (*) (void *, void *)) (freefun), (arg)) | |
222 | ||
223 | #define obstack_chunkfun(h, newchunkfun) \ | |
224 | ((h) -> chunkfun = (struct _obstack_chunk *(*)(void *, long)) (newchunkfun)) | |
225 | ||
226 | #define obstack_freefun(h, newfreefun) \ | |
227 | ((h) -> freefun = (void (*)(void *, struct _obstack_chunk *)) (newfreefun)) | |
228 | ||
229 | #define obstack_1grow_fast(h,achar) (*((h)->next_free)++ = (achar)) | |
230 | ||
231 | #define obstack_blank_fast(h,n) ((h)->next_free += (n)) | |
232 | ||
233 | #define obstack_memory_used(h) _obstack_memory_used (h) | |
234 | \f | |
235 | #if defined __GNUC__ | |
236 | /* NextStep 2.0 cc is really gcc 1.93 but it defines __GNUC__ = 2 and | |
237 | does not implement __extension__. But that compiler doesn't define | |
238 | __GNUC_MINOR__. */ | |
239 | # if __GNUC__ < 2 || (__NeXT__ && !__GNUC_MINOR__) | |
240 | # define __extension__ | |
241 | # endif | |
242 | ||
243 | /* For GNU C, if not -traditional, | |
244 | we can define these macros to compute all args only once | |
245 | without using a global variable. | |
246 | Also, we can avoid using the `temp' slot, to make faster code. */ | |
247 | ||
248 | # define obstack_object_size(OBSTACK) \ | |
249 | __extension__ \ | |
250 | ({ struct obstack const *__o = (OBSTACK); \ | |
251 | (unsigned) (__o->next_free - __o->object_base); }) | |
252 | ||
253 | # define obstack_room(OBSTACK) \ | |
254 | __extension__ \ | |
255 | ({ struct obstack const *__o = (OBSTACK); \ | |
256 | (unsigned) (__o->chunk_limit - __o->next_free); }) | |
257 | ||
258 | # define obstack_make_room(OBSTACK,length) \ | |
259 | __extension__ \ | |
260 | ({ struct obstack *__o = (OBSTACK); \ | |
261 | int __len = (length); \ | |
262 | if (__o->chunk_limit - __o->next_free < __len) \ | |
263 | _obstack_newchunk (__o, __len); \ | |
264 | (void) 0; }) | |
265 | ||
266 | # define obstack_empty_p(OBSTACK) \ | |
267 | __extension__ \ | |
268 | ({ struct obstack const *__o = (OBSTACK); \ | |
269 | (__o->chunk->prev == 0 \ | |
270 | && __o->next_free == __PTR_ALIGN ((char *) __o->chunk, \ | |
271 | __o->chunk->contents, \ | |
272 | __o->alignment_mask)); }) | |
273 | ||
274 | # define obstack_grow(OBSTACK,where,length) \ | |
275 | __extension__ \ | |
276 | ({ struct obstack *__o = (OBSTACK); \ | |
277 | int __len = (length); \ | |
278 | if (__o->next_free + __len > __o->chunk_limit) \ | |
279 | _obstack_newchunk (__o, __len); \ | |
280 | memcpy (__o->next_free, where, __len); \ | |
281 | __o->next_free += __len; \ | |
282 | (void) 0; }) | |
283 | ||
284 | # define obstack_grow0(OBSTACK,where,length) \ | |
285 | __extension__ \ | |
286 | ({ struct obstack *__o = (OBSTACK); \ | |
287 | int __len = (length); \ | |
288 | if (__o->next_free + __len + 1 > __o->chunk_limit) \ | |
289 | _obstack_newchunk (__o, __len + 1); \ | |
290 | memcpy (__o->next_free, where, __len); \ | |
291 | __o->next_free += __len; \ | |
292 | *(__o->next_free)++ = 0; \ | |
293 | (void) 0; }) | |
294 | ||
295 | # define obstack_1grow(OBSTACK,datum) \ | |
296 | __extension__ \ | |
297 | ({ struct obstack *__o = (OBSTACK); \ | |
298 | if (__o->next_free + 1 > __o->chunk_limit) \ | |
299 | _obstack_newchunk (__o, 1); \ | |
300 | obstack_1grow_fast (__o, datum); \ | |
301 | (void) 0; }) | |
302 | ||
303 | /* These assume that the obstack alignment is good enough for pointers | |
304 | or ints, and that the data added so far to the current object | |
305 | shares that much alignment. */ | |
306 | ||
307 | # define obstack_ptr_grow(OBSTACK,datum) \ | |
308 | __extension__ \ | |
309 | ({ struct obstack *__o = (OBSTACK); \ | |
310 | if (__o->next_free + sizeof (void *) > __o->chunk_limit) \ | |
311 | _obstack_newchunk (__o, sizeof (void *)); \ | |
312 | obstack_ptr_grow_fast (__o, datum); }) \ | |
313 | ||
314 | # define obstack_int_grow(OBSTACK,datum) \ | |
315 | __extension__ \ | |
316 | ({ struct obstack *__o = (OBSTACK); \ | |
317 | if (__o->next_free + sizeof (int) > __o->chunk_limit) \ | |
318 | _obstack_newchunk (__o, sizeof (int)); \ | |
319 | obstack_int_grow_fast (__o, datum); }) | |
320 | ||
321 | # define obstack_ptr_grow_fast(OBSTACK,aptr) \ | |
322 | __extension__ \ | |
323 | ({ struct obstack *__o1 = (OBSTACK); \ | |
324 | *(const void **) __o1->next_free = (aptr); \ | |
325 | __o1->next_free += sizeof (const void *); \ | |
326 | (void) 0; }) | |
327 | ||
328 | # define obstack_int_grow_fast(OBSTACK,aint) \ | |
329 | __extension__ \ | |
330 | ({ struct obstack *__o1 = (OBSTACK); \ | |
331 | *(int *) __o1->next_free = (aint); \ | |
332 | __o1->next_free += sizeof (int); \ | |
333 | (void) 0; }) | |
334 | ||
335 | # define obstack_blank(OBSTACK,length) \ | |
336 | __extension__ \ | |
337 | ({ struct obstack *__o = (OBSTACK); \ | |
338 | int __len = (length); \ | |
339 | if (__o->chunk_limit - __o->next_free < __len) \ | |
340 | _obstack_newchunk (__o, __len); \ | |
341 | obstack_blank_fast (__o, __len); \ | |
342 | (void) 0; }) | |
343 | ||
344 | # define obstack_alloc(OBSTACK,length) \ | |
345 | __extension__ \ | |
346 | ({ struct obstack *__h = (OBSTACK); \ | |
347 | obstack_blank (__h, (length)); \ | |
348 | obstack_finish (__h); }) | |
349 | ||
350 | # define obstack_copy(OBSTACK,where,length) \ | |
351 | __extension__ \ | |
352 | ({ struct obstack *__h = (OBSTACK); \ | |
353 | obstack_grow (__h, (where), (length)); \ | |
354 | obstack_finish (__h); }) | |
355 | ||
356 | # define obstack_copy0(OBSTACK,where,length) \ | |
357 | __extension__ \ | |
358 | ({ struct obstack *__h = (OBSTACK); \ | |
359 | obstack_grow0 (__h, (where), (length)); \ | |
360 | obstack_finish (__h); }) | |
361 | ||
362 | /* The local variable is named __o1 to avoid a name conflict | |
363 | when obstack_blank is called. */ | |
364 | # define obstack_finish(OBSTACK) \ | |
365 | __extension__ \ | |
366 | ({ struct obstack *__o1 = (OBSTACK); \ | |
367 | void *__value = (void *) __o1->object_base; \ | |
368 | if (__o1->next_free == __value) \ | |
369 | __o1->maybe_empty_object = 1; \ | |
370 | __o1->next_free \ | |
371 | = __PTR_ALIGN (__o1->object_base, __o1->next_free, \ | |
372 | __o1->alignment_mask); \ | |
373 | if (__o1->next_free - (char *)__o1->chunk \ | |
374 | > __o1->chunk_limit - (char *)__o1->chunk) \ | |
375 | __o1->next_free = __o1->chunk_limit; \ | |
376 | __o1->object_base = __o1->next_free; \ | |
377 | __value; }) | |
378 | ||
379 | # define obstack_free(OBSTACK, OBJ) \ | |
380 | __extension__ \ | |
381 | ({ struct obstack *__o = (OBSTACK); \ | |
382 | void *__obj = (OBJ); \ | |
383 | if (__obj > (void *)__o->chunk && __obj < (void *)__o->chunk_limit) \ | |
384 | __o->next_free = __o->object_base = (char *)__obj; \ | |
385 | else (obstack_free_func) (__o, __obj); }) | |
386 | \f | |
387 | #else /* not __GNUC__ */ | |
388 | ||
389 | # define obstack_object_size(h) \ | |
390 | (unsigned) ((h)->next_free - (h)->object_base) | |
391 | ||
392 | # define obstack_room(h) \ | |
393 | (unsigned) ((h)->chunk_limit - (h)->next_free) | |
394 | ||
395 | # define obstack_empty_p(h) \ | |
396 | ((h)->chunk->prev == 0 \ | |
397 | && (h)->next_free == __PTR_ALIGN ((char *) (h)->chunk, \ | |
398 | (h)->chunk->contents, \ | |
399 | (h)->alignment_mask)) | |
400 | ||
401 | /* Note that the call to _obstack_newchunk is enclosed in (..., 0) | |
402 | so that we can avoid having void expressions | |
403 | in the arms of the conditional expression. | |
404 | Casting the third operand to void was tried before, | |
405 | but some compilers won't accept it. */ | |
406 | ||
407 | # define obstack_make_room(h,length) \ | |
408 | ( (h)->temp.tempint = (length), \ | |
409 | (((h)->next_free + (h)->temp.tempint > (h)->chunk_limit) \ | |
410 | ? (_obstack_newchunk ((h), (h)->temp.tempint), 0) : 0)) | |
411 | ||
412 | # define obstack_grow(h,where,length) \ | |
413 | ( (h)->temp.tempint = (length), \ | |
414 | (((h)->next_free + (h)->temp.tempint > (h)->chunk_limit) \ | |
415 | ? (_obstack_newchunk ((h), (h)->temp.tempint), 0) : 0), \ | |
416 | memcpy ((h)->next_free, where, (h)->temp.tempint), \ | |
417 | (h)->next_free += (h)->temp.tempint) | |
418 | ||
419 | # define obstack_grow0(h,where,length) \ | |
420 | ( (h)->temp.tempint = (length), \ | |
421 | (((h)->next_free + (h)->temp.tempint + 1 > (h)->chunk_limit) \ | |
422 | ? (_obstack_newchunk ((h), (h)->temp.tempint + 1), 0) : 0), \ | |
423 | memcpy ((h)->next_free, where, (h)->temp.tempint), \ | |
424 | (h)->next_free += (h)->temp.tempint, \ | |
425 | *((h)->next_free)++ = 0) | |
426 | ||
427 | # define obstack_1grow(h,datum) \ | |
428 | ( (((h)->next_free + 1 > (h)->chunk_limit) \ | |
429 | ? (_obstack_newchunk ((h), 1), 0) : 0), \ | |
430 | obstack_1grow_fast (h, datum)) | |
431 | ||
432 | # define obstack_ptr_grow(h,datum) \ | |
433 | ( (((h)->next_free + sizeof (char *) > (h)->chunk_limit) \ | |
434 | ? (_obstack_newchunk ((h), sizeof (char *)), 0) : 0), \ | |
435 | obstack_ptr_grow_fast (h, datum)) | |
436 | ||
437 | # define obstack_int_grow(h,datum) \ | |
438 | ( (((h)->next_free + sizeof (int) > (h)->chunk_limit) \ | |
439 | ? (_obstack_newchunk ((h), sizeof (int)), 0) : 0), \ | |
440 | obstack_int_grow_fast (h, datum)) | |
441 | ||
442 | # define obstack_ptr_grow_fast(h,aptr) \ | |
443 | (((const void **) ((h)->next_free += sizeof (void *)))[-1] = (aptr)) | |
444 | ||
445 | # define obstack_int_grow_fast(h,aint) \ | |
446 | (((int *) ((h)->next_free += sizeof (int)))[-1] = (aint)) | |
447 | ||
448 | # define obstack_blank(h,length) \ | |
449 | ( (h)->temp.tempint = (length), \ | |
450 | (((h)->chunk_limit - (h)->next_free < (h)->temp.tempint) \ | |
451 | ? (_obstack_newchunk ((h), (h)->temp.tempint), 0) : 0), \ | |
452 | obstack_blank_fast (h, (h)->temp.tempint)) | |
453 | ||
454 | # define obstack_alloc(h,length) \ | |
455 | (obstack_blank ((h), (length)), obstack_finish ((h))) | |
456 | ||
457 | # define obstack_copy(h,where,length) \ | |
458 | (obstack_grow ((h), (where), (length)), obstack_finish ((h))) | |
459 | ||
460 | # define obstack_copy0(h,where,length) \ | |
461 | (obstack_grow0 ((h), (where), (length)), obstack_finish ((h))) | |
462 | ||
463 | # define obstack_finish(h) \ | |
464 | ( ((h)->next_free == (h)->object_base \ | |
465 | ? (((h)->maybe_empty_object = 1), 0) \ | |
466 | : 0), \ | |
467 | (h)->temp.tempptr = (h)->object_base, \ | |
468 | (h)->next_free \ | |
469 | = __PTR_ALIGN ((h)->object_base, (h)->next_free, \ | |
470 | (h)->alignment_mask), \ | |
471 | (((h)->next_free - (char *) (h)->chunk \ | |
472 | > (h)->chunk_limit - (char *) (h)->chunk) \ | |
473 | ? ((h)->next_free = (h)->chunk_limit) : 0), \ | |
474 | (h)->object_base = (h)->next_free, \ | |
475 | (h)->temp.tempptr) | |
476 | ||
477 | # define obstack_free(h,obj) \ | |
478 | ( (h)->temp.tempint = (char *) (obj) - (char *) (h)->chunk, \ | |
479 | ((((h)->temp.tempint > 0 \ | |
480 | && (h)->temp.tempint < (h)->chunk_limit - (char *) (h)->chunk)) \ | |
481 | ? (((h)->next_free = (h)->object_base \ | |
482 | = (h)->temp.tempint + (char *) (h)->chunk), 0) \ | |
483 | : ((obstack_free_func) ((h), (h)->temp.tempint + (char *) (h)->chunk), 0))) | |
484 | ||
485 | #endif /* not __GNUC__ */ | |
486 | ||
487 | /* START LOCAL ADDITION */ | |
488 | static inline int obstack_printf(struct obstack *obst, const char *fmt, ...) | |
489 | { | |
490 | char buf[1024]; | |
491 | va_list ap; | |
492 | int len; | |
493 | ||
494 | va_start(ap, fmt); | |
495 | len = vsnprintf(buf, sizeof(buf), fmt, ap); | |
496 | obstack_grow(obst, buf, len); | |
497 | va_end(ap); | |
498 | ||
499 | return len; | |
500 | } | |
501 | /* Determine default alignment. */ | |
502 | union fooround | |
503 | { | |
504 | uintmax_t i; | |
505 | long double d; | |
506 | void *p; | |
507 | }; | |
508 | struct fooalign | |
509 | { | |
510 | char c; | |
511 | union fooround u; | |
512 | }; | |
513 | /* If malloc were really smart, it would round addresses to DEFAULT_ALIGNMENT. | |
514 | But in fact it might be less smart and round addresses to as much as | |
515 | DEFAULT_ROUNDING. So we prepare for it to do that. */ | |
516 | enum | |
517 | { | |
518 | DEFAULT_ALIGNMENT = offsetof (struct fooalign, u), | |
519 | DEFAULT_ROUNDING = sizeof (union fooround) | |
520 | }; | |
521 | ||
522 | /* When we copy a long block of data, this is the unit to do it with. | |
523 | On some machines, copying successive ints does not work; | |
524 | in such a case, redefine COPYING_UNIT to `long' (if that works) | |
525 | or `char' as a last resort. */ | |
526 | # ifndef COPYING_UNIT | |
527 | # define COPYING_UNIT int | |
528 | # endif | |
529 | ||
530 | ||
531 | /* The functions allocating more room by calling `obstack_chunk_alloc' | |
532 | jump to the handler pointed to by `obstack_alloc_failed_handler'. | |
533 | This can be set to a user defined function which should either | |
534 | abort gracefully or use longjump - but shouldn't return. This | |
535 | variable by default points to the internal function | |
536 | `print_and_abort'. */ | |
537 | static void print_and_abort (void); | |
538 | ||
539 | # ifdef _LIBC | |
540 | # if SHLIB_COMPAT (libc, GLIBC_2_0, GLIBC_2_3_4) | |
541 | /* A looong time ago (before 1994, anyway; we're not sure) this global variable | |
542 | was used by non-GNU-C macros to avoid multiple evaluation. The GNU C | |
543 | library still exports it because somebody might use it. */ | |
544 | struct obstack *_obstack_compat; | |
545 | compat_symbol (libc, _obstack_compat, _obstack, GLIBC_2_0); | |
546 | # endif | |
547 | # endif | |
548 | ||
549 | /* Define a macro that either calls functions with the traditional malloc/free | |
550 | calling interface, or calls functions with the mmalloc/mfree interface | |
551 | (that adds an extra first argument), based on the state of use_extra_arg. | |
552 | For free, do not use ?:, since some compilers, like the MIPS compilers, | |
553 | do not allow (expr) ? void : void. */ | |
554 | ||
555 | # define CALL_CHUNKFUN(h, size) \ | |
556 | (((h) -> use_extra_arg) \ | |
557 | ? (*(h)->chunkfun) ((h)->extra_arg, (size)) \ | |
558 | : (*(struct _obstack_chunk *(*) (long)) (h)->chunkfun) ((size))) | |
559 | ||
560 | # define CALL_FREEFUN(h, old_chunk) \ | |
561 | do { \ | |
562 | if ((h) -> use_extra_arg) \ | |
563 | (*(h)->freefun) ((h)->extra_arg, (old_chunk)); \ | |
564 | else \ | |
565 | (*(void (*) (void *)) (h)->freefun) ((old_chunk)); \ | |
566 | } while (0) | |
567 | ||
568 | \f | |
569 | /* Initialize an obstack H for use. Specify chunk size SIZE (0 means default). | |
570 | Objects start on multiples of ALIGNMENT (0 means use default). | |
571 | CHUNKFUN is the function to use to allocate chunks, | |
572 | and FREEFUN the function to free them. | |
573 | Return nonzero if successful, calls obstack_alloc_failed_handler if | |
574 | allocation fails. */ | |
575 | ||
576 | static int _obstack_begin (struct obstack *h, | |
577 | int size, int alignment, | |
578 | void *(*chunkfun) (long), | |
579 | void (*freefun) (void *)) | |
580 | { | |
581 | register struct _obstack_chunk *chunk; /* points to new chunk */ | |
582 | ||
583 | if (alignment == 0) | |
584 | alignment = DEFAULT_ALIGNMENT; | |
585 | if (size == 0) | |
586 | /* Default size is what GNU malloc can fit in a 4096-byte block. */ | |
587 | { | |
588 | /* 12 is sizeof (mhead) and 4 is EXTRA from GNU malloc. | |
589 | Use the values for range checking, because if range checking is off, | |
590 | the extra bytes won't be missed terribly, but if range checking is on | |
591 | and we used a larger request, a whole extra 4096 bytes would be | |
592 | allocated. | |
593 | These number are irrelevant to the new GNU malloc. I suspect it is | |
594 | less sensitive to the size of the request. */ | |
595 | int extra = ((((12 + DEFAULT_ROUNDING - 1) & ~(DEFAULT_ROUNDING - 1)) | |
596 | + 4 + DEFAULT_ROUNDING - 1) | |
597 | & ~(DEFAULT_ROUNDING - 1)); | |
598 | size = 4096 - extra; | |
599 | } | |
600 | ||
601 | h->chunkfun = (struct _obstack_chunk * (*)(void *, long)) chunkfun; | |
602 | h->freefun = (void (*) (void *, struct _obstack_chunk *)) freefun; | |
603 | h->chunk_size = size; | |
604 | h->alignment_mask = alignment - 1; | |
605 | h->use_extra_arg = 0; | |
606 | ||
607 | chunk = h->chunk = CALL_CHUNKFUN (h, h -> chunk_size); | |
608 | if (!chunk) print_and_abort(); | |
609 | h->next_free = h->object_base = __PTR_ALIGN ((char *) chunk, chunk->contents, | |
610 | alignment - 1); | |
611 | h->chunk_limit = chunk->limit | |
612 | = (char *) chunk + h->chunk_size; | |
613 | chunk->prev = 0; | |
614 | /* The initial chunk now contains no empty object. */ | |
615 | h->maybe_empty_object = 0; | |
616 | h->alloc_failed = 0; | |
617 | return 1; | |
618 | } | |
619 | ||
620 | static int _obstack_begin_1 (struct obstack *h, int size, int alignment, | |
621 | void *(*chunkfun) (void *, long), | |
622 | void (*freefun) (void *, void *), | |
623 | void *arg) | |
624 | { | |
625 | register struct _obstack_chunk *chunk; /* points to new chunk */ | |
626 | ||
627 | if (alignment == 0) | |
628 | alignment = DEFAULT_ALIGNMENT; | |
629 | if (size == 0) | |
630 | /* Default size is what GNU malloc can fit in a 4096-byte block. */ | |
631 | { | |
632 | /* 12 is sizeof (mhead) and 4 is EXTRA from GNU malloc. | |
633 | Use the values for range checking, because if range checking is off, | |
634 | the extra bytes won't be missed terribly, but if range checking is on | |
635 | and we used a larger request, a whole extra 4096 bytes would be | |
636 | allocated. | |
637 | These number are irrelevant to the new GNU malloc. I suspect it is | |
638 | less sensitive to the size of the request. */ | |
639 | int extra = ((((12 + DEFAULT_ROUNDING - 1) & ~(DEFAULT_ROUNDING - 1)) | |
640 | + 4 + DEFAULT_ROUNDING - 1) | |
641 | & ~(DEFAULT_ROUNDING - 1)); | |
642 | size = 4096 - extra; | |
643 | } | |
644 | ||
645 | h->chunkfun = (struct _obstack_chunk * (*)(void *,long)) chunkfun; | |
646 | h->freefun = (void (*) (void *, struct _obstack_chunk *)) freefun; | |
647 | h->chunk_size = size; | |
648 | h->alignment_mask = alignment - 1; | |
649 | h->extra_arg = arg; | |
650 | h->use_extra_arg = 1; | |
651 | ||
652 | chunk = h->chunk = CALL_CHUNKFUN (h, h -> chunk_size); | |
653 | if (!chunk) print_and_abort(); | |
654 | h->next_free = h->object_base = __PTR_ALIGN ((char *) chunk, chunk->contents, | |
655 | alignment - 1); | |
656 | h->chunk_limit = chunk->limit | |
657 | = (char *) chunk + h->chunk_size; | |
658 | chunk->prev = 0; | |
659 | /* The initial chunk now contains no empty object. */ | |
660 | h->maybe_empty_object = 0; | |
661 | h->alloc_failed = 0; | |
662 | return 1; | |
663 | } | |
664 | ||
665 | /* Allocate a new current chunk for the obstack *H | |
666 | on the assumption that LENGTH bytes need to be added | |
667 | to the current object, or a new object of length LENGTH allocated. | |
668 | Copies any partial object from the end of the old chunk | |
669 | to the beginning of the new one. */ | |
670 | ||
671 | static void _obstack_newchunk (struct obstack *h, int length) | |
672 | { | |
673 | register struct _obstack_chunk *old_chunk = h->chunk; | |
674 | register struct _obstack_chunk *new_chunk; | |
675 | register long new_size; | |
676 | register long obj_size = h->next_free - h->object_base; | |
677 | register long i; | |
678 | long already; | |
679 | char *object_base; | |
680 | ||
681 | /* Compute size for new chunk. */ | |
682 | new_size = (obj_size + length) + (obj_size >> 3) + h->alignment_mask + 100; | |
683 | if (new_size < h->chunk_size) | |
684 | new_size = h->chunk_size; | |
685 | ||
686 | /* Allocate and initialize the new chunk. */ | |
687 | new_chunk = CALL_CHUNKFUN (h, new_size); | |
688 | if (!new_chunk) print_and_abort(); | |
689 | h->chunk = new_chunk; | |
690 | new_chunk->prev = old_chunk; | |
691 | new_chunk->limit = h->chunk_limit = (char *) new_chunk + new_size; | |
692 | ||
693 | /* Compute an aligned object_base in the new chunk */ | |
694 | object_base = | |
695 | __PTR_ALIGN ((char *) new_chunk, new_chunk->contents, h->alignment_mask); | |
696 | ||
697 | /* Move the existing object to the new chunk. | |
698 | Word at a time is fast and is safe if the object | |
699 | is sufficiently aligned. */ | |
700 | if (h->alignment_mask + 1 >= DEFAULT_ALIGNMENT) | |
701 | { | |
702 | for (i = obj_size / sizeof (COPYING_UNIT) - 1; | |
703 | i >= 0; i--) | |
704 | ((COPYING_UNIT *)object_base)[i] | |
705 | = ((COPYING_UNIT *)h->object_base)[i]; | |
706 | /* We used to copy the odd few remaining bytes as one extra COPYING_UNIT, | |
707 | but that can cross a page boundary on a machine | |
708 | which does not do strict alignment for COPYING_UNITS. */ | |
709 | already = obj_size / sizeof (COPYING_UNIT) * sizeof (COPYING_UNIT); | |
710 | } | |
711 | else | |
712 | already = 0; | |
713 | /* Copy remaining bytes one by one. */ | |
714 | for (i = already; i < obj_size; i++) | |
715 | object_base[i] = h->object_base[i]; | |
716 | ||
717 | /* If the object just copied was the only data in OLD_CHUNK, | |
718 | free that chunk and remove it from the chain. | |
719 | But not if that chunk might contain an empty object. */ | |
720 | if (! h->maybe_empty_object | |
721 | && (h->object_base | |
722 | == __PTR_ALIGN ((char *) old_chunk, old_chunk->contents, | |
723 | h->alignment_mask))) | |
724 | { | |
725 | new_chunk->prev = old_chunk->prev; | |
726 | CALL_FREEFUN (h, old_chunk); | |
727 | } | |
728 | ||
729 | h->object_base = object_base; | |
730 | h->next_free = h->object_base + obj_size; | |
731 | /* The new chunk certainly contains no empty object yet. */ | |
732 | h->maybe_empty_object = 0; | |
733 | } | |
734 | ||
735 | /* Return nonzero if object OBJ has been allocated from obstack H. | |
736 | This is here for debugging. | |
737 | If you use it in a program, you are probably losing. */ | |
738 | ||
739 | /* Free objects in obstack H, including OBJ and everything allocate | |
740 | more recently than OBJ. If OBJ is zero, free everything in H. */ | |
741 | static void obstack_free_func (struct obstack *h, void *obj) | |
742 | { | |
743 | register struct _obstack_chunk *lp; /* below addr of any objects in this chunk */ | |
744 | register struct _obstack_chunk *plp; /* point to previous chunk if any */ | |
745 | ||
746 | lp = h->chunk; | |
747 | /* We use >= because there cannot be an object at the beginning of a chunk. | |
748 | But there can be an empty object at that address | |
749 | at the end of another chunk. */ | |
750 | while (lp != 0 && ((void *) lp >= obj || (void *) (lp)->limit < obj)) | |
751 | { | |
752 | plp = lp->prev; | |
753 | CALL_FREEFUN (h, lp); | |
754 | lp = plp; | |
755 | /* If we switch chunks, we can't tell whether the new current | |
756 | chunk contains an empty object, so assume that it may. */ | |
757 | h->maybe_empty_object = 1; | |
758 | } | |
759 | if (lp) | |
760 | { | |
761 | h->object_base = h->next_free = (char *) (obj); | |
762 | h->chunk_limit = lp->limit; | |
763 | h->chunk = lp; | |
764 | } | |
765 | else if (obj != 0) | |
766 | /* obj is not in any of the chunks! */ | |
767 | abort (); | |
768 | } | |
769 | ||
770 | static int _obstack_memory_used (struct obstack *h) | |
771 | { | |
772 | register struct _obstack_chunk* lp; | |
773 | register int nbytes = 0; | |
774 | ||
775 | for (lp = h->chunk; lp != 0; lp = lp->prev) | |
776 | { | |
777 | nbytes += lp->limit - (char *) lp; | |
778 | } | |
779 | return nbytes; | |
780 | } | |
781 | ||
782 | static void __attribute__ ((noreturn)) print_and_abort (void) | |
783 | { | |
784 | fprintf(stderr, "%s\n", "memory exhausted"); | |
785 | exit(1); | |
786 | } | |
787 | ||
788 | /* END LOCAL ADDITION */ | |
789 | ||
790 | #ifdef __cplusplus | |
791 | } /* C++ */ | |
792 | #endif | |
793 | ||
794 | #endif /* obstack.h */ |