| 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 */ |