Fredrik Kuivinen | e831171 | 2011-08-21 00:40:40 +0200 | [diff] [blame] | 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 |
Todd Zullinger | 4842579 | 2017-11-07 00:39:33 -0500 | [diff] [blame] | 17 | License along with the GNU C Library; if not, see |
| 18 | <http://www.gnu.org/licenses/>. */ |
Fredrik Kuivinen | e831171 | 2011-08-21 00:40:40 +0200 | [diff] [blame] | 19 | |
Fredrik Kuivinen | d190a08 | 2011-08-28 22:08:46 +0200 | [diff] [blame] | 20 | #include "git-compat-util.h" |
| 21 | #include <gettext.h> |
| 22 | #include "obstack.h" |
Fredrik Kuivinen | e831171 | 2011-08-21 00:40:40 +0200 | [diff] [blame] | 23 | |
| 24 | /* NOTE BEFORE MODIFYING THIS FILE: This version number must be |
| 25 | incremented whenever callers compiled using an old obstack.h can no |
| 26 | longer properly call the functions in this obstack.c. */ |
| 27 | #define OBSTACK_INTERFACE_VERSION 1 |
| 28 | |
| 29 | /* Comment out all this code if we are using the GNU C Library, and are not |
| 30 | actually compiling the library itself, and the installed library |
| 31 | supports the same library interface we do. This code is part of the GNU |
| 32 | C Library, but also included in many other GNU distributions. Compiling |
| 33 | and linking in this code is a waste when using the GNU C library |
| 34 | (especially if it is a shared library). Rather than having every GNU |
| 35 | program understand `configure --with-gnu-libc' and omit the object |
| 36 | files, it is simpler to just do this in the source for each such file. */ |
| 37 | |
| 38 | #include <stdio.h> /* Random thing to get __GNU_LIBRARY__. */ |
| 39 | #if !defined _LIBC && defined __GNU_LIBRARY__ && __GNU_LIBRARY__ > 1 |
| 40 | # include <gnu-versions.h> |
| 41 | # if _GNU_OBSTACK_INTERFACE_VERSION == OBSTACK_INTERFACE_VERSION |
| 42 | # define ELIDE_CODE |
| 43 | # endif |
| 44 | #endif |
| 45 | |
| 46 | #include <stddef.h> |
| 47 | |
| 48 | #ifndef ELIDE_CODE |
| 49 | |
| 50 | |
| 51 | # if HAVE_INTTYPES_H |
| 52 | # include <inttypes.h> |
| 53 | # endif |
| 54 | # if HAVE_STDINT_H || defined _LIBC |
| 55 | # include <stdint.h> |
| 56 | # endif |
| 57 | |
| 58 | /* Determine default alignment. */ |
| 59 | union fooround |
| 60 | { |
| 61 | uintmax_t i; |
| 62 | long double d; |
| 63 | void *p; |
| 64 | }; |
| 65 | struct fooalign |
| 66 | { |
| 67 | char c; |
| 68 | union fooround u; |
| 69 | }; |
| 70 | /* If malloc were really smart, it would round addresses to DEFAULT_ALIGNMENT. |
| 71 | But in fact it might be less smart and round addresses to as much as |
| 72 | DEFAULT_ROUNDING. So we prepare for it to do that. */ |
| 73 | enum |
| 74 | { |
| 75 | DEFAULT_ALIGNMENT = offsetof (struct fooalign, u), |
| 76 | DEFAULT_ROUNDING = sizeof (union fooround) |
| 77 | }; |
| 78 | |
| 79 | /* When we copy a long block of data, this is the unit to do it with. |
| 80 | On some machines, copying successive ints does not work; |
| 81 | in such a case, redefine COPYING_UNIT to `long' (if that works) |
| 82 | or `char' as a last resort. */ |
| 83 | # ifndef COPYING_UNIT |
| 84 | # define COPYING_UNIT int |
| 85 | # endif |
| 86 | |
| 87 | |
| 88 | /* The functions allocating more room by calling `obstack_chunk_alloc' |
| 89 | jump to the handler pointed to by `obstack_alloc_failed_handler'. |
| 90 | This can be set to a user defined function which should either |
| 91 | abort gracefully or use longjump - but shouldn't return. This |
| 92 | variable by default points to the internal function |
| 93 | `print_and_abort'. */ |
| 94 | static void print_and_abort (void); |
| 95 | void (*obstack_alloc_failed_handler) (void) = print_and_abort; |
| 96 | |
Fredrik Kuivinen | e831171 | 2011-08-21 00:40:40 +0200 | [diff] [blame] | 97 | # ifdef _LIBC |
| 98 | # if SHLIB_COMPAT (libc, GLIBC_2_0, GLIBC_2_3_4) |
| 99 | /* A looong time ago (before 1994, anyway; we're not sure) this global variable |
| 100 | was used by non-GNU-C macros to avoid multiple evaluation. The GNU C |
| 101 | library still exports it because somebody might use it. */ |
| 102 | struct obstack *_obstack_compat; |
| 103 | compat_symbol (libc, _obstack_compat, _obstack, GLIBC_2_0); |
| 104 | # endif |
| 105 | # endif |
| 106 | |
| 107 | /* Define a macro that either calls functions with the traditional malloc/free |
| 108 | calling interface, or calls functions with the mmalloc/mfree interface |
| 109 | (that adds an extra first argument), based on the state of use_extra_arg. |
| 110 | For free, do not use ?:, since some compilers, like the MIPS compilers, |
| 111 | do not allow (expr) ? void : void. */ |
| 112 | |
| 113 | # define CALL_CHUNKFUN(h, size) \ |
| 114 | (((h) -> use_extra_arg) \ |
SZEDER Gábor | 764473d | 2019-01-17 02:29:09 +0100 | [diff] [blame] | 115 | ? (*(h)->chunkfun.extra) ((h)->extra_arg, (size)) \ |
| 116 | : (*(h)->chunkfun.plain) ((size))) |
Fredrik Kuivinen | e831171 | 2011-08-21 00:40:40 +0200 | [diff] [blame] | 117 | |
| 118 | # define CALL_FREEFUN(h, old_chunk) \ |
| 119 | do { \ |
| 120 | if ((h) -> use_extra_arg) \ |
SZEDER Gábor | 764473d | 2019-01-17 02:29:09 +0100 | [diff] [blame] | 121 | (*(h)->freefun.extra) ((h)->extra_arg, (old_chunk)); \ |
Fredrik Kuivinen | e831171 | 2011-08-21 00:40:40 +0200 | [diff] [blame] | 122 | else \ |
SZEDER Gábor | 764473d | 2019-01-17 02:29:09 +0100 | [diff] [blame] | 123 | (*(h)->freefun.plain) ((old_chunk)); \ |
Fredrik Kuivinen | e831171 | 2011-08-21 00:40:40 +0200 | [diff] [blame] | 124 | } while (0) |
| 125 | |
| 126 | |
| 127 | /* Initialize an obstack H for use. Specify chunk size SIZE (0 means default). |
| 128 | Objects start on multiples of ALIGNMENT (0 means use default). |
| 129 | CHUNKFUN is the function to use to allocate chunks, |
| 130 | and FREEFUN the function to free them. |
| 131 | |
| 132 | Return nonzero if successful, calls obstack_alloc_failed_handler if |
| 133 | allocation fails. */ |
| 134 | |
| 135 | int |
| 136 | _obstack_begin (struct obstack *h, |
| 137 | int size, int alignment, |
| 138 | void *(*chunkfun) (long), |
| 139 | void (*freefun) (void *)) |
| 140 | { |
| 141 | register struct _obstack_chunk *chunk; /* points to new chunk */ |
| 142 | |
| 143 | if (alignment == 0) |
| 144 | alignment = DEFAULT_ALIGNMENT; |
| 145 | if (size == 0) |
| 146 | /* Default size is what GNU malloc can fit in a 4096-byte block. */ |
| 147 | { |
| 148 | /* 12 is sizeof (mhead) and 4 is EXTRA from GNU malloc. |
| 149 | Use the values for range checking, because if range checking is off, |
| 150 | the extra bytes won't be missed terribly, but if range checking is on |
| 151 | and we used a larger request, a whole extra 4096 bytes would be |
| 152 | allocated. |
| 153 | |
| 154 | These number are irrelevant to the new GNU malloc. I suspect it is |
| 155 | less sensitive to the size of the request. */ |
| 156 | int extra = ((((12 + DEFAULT_ROUNDING - 1) & ~(DEFAULT_ROUNDING - 1)) |
| 157 | + 4 + DEFAULT_ROUNDING - 1) |
| 158 | & ~(DEFAULT_ROUNDING - 1)); |
| 159 | size = 4096 - extra; |
| 160 | } |
| 161 | |
SZEDER Gábor | 764473d | 2019-01-17 02:29:09 +0100 | [diff] [blame] | 162 | h->chunkfun.plain = chunkfun; |
| 163 | h->freefun.plain = freefun; |
Fredrik Kuivinen | e831171 | 2011-08-21 00:40:40 +0200 | [diff] [blame] | 164 | h->chunk_size = size; |
| 165 | h->alignment_mask = alignment - 1; |
| 166 | h->use_extra_arg = 0; |
| 167 | |
| 168 | chunk = h->chunk = CALL_CHUNKFUN (h, h -> chunk_size); |
| 169 | if (!chunk) |
| 170 | (*obstack_alloc_failed_handler) (); |
| 171 | h->next_free = h->object_base = __PTR_ALIGN ((char *) chunk, chunk->contents, |
| 172 | alignment - 1); |
| 173 | h->chunk_limit = chunk->limit |
| 174 | = (char *) chunk + h->chunk_size; |
Ramsay Jones | 3254310 | 2011-09-11 20:26:53 +0100 | [diff] [blame] | 175 | chunk->prev = NULL; |
Fredrik Kuivinen | e831171 | 2011-08-21 00:40:40 +0200 | [diff] [blame] | 176 | /* The initial chunk now contains no empty object. */ |
| 177 | h->maybe_empty_object = 0; |
| 178 | h->alloc_failed = 0; |
| 179 | return 1; |
| 180 | } |
| 181 | |
| 182 | int |
| 183 | _obstack_begin_1 (struct obstack *h, int size, int alignment, |
| 184 | void *(*chunkfun) (void *, long), |
| 185 | void (*freefun) (void *, void *), |
| 186 | void *arg) |
| 187 | { |
| 188 | register struct _obstack_chunk *chunk; /* points to new chunk */ |
| 189 | |
| 190 | if (alignment == 0) |
| 191 | alignment = DEFAULT_ALIGNMENT; |
| 192 | if (size == 0) |
| 193 | /* Default size is what GNU malloc can fit in a 4096-byte block. */ |
| 194 | { |
| 195 | /* 12 is sizeof (mhead) and 4 is EXTRA from GNU malloc. |
| 196 | Use the values for range checking, because if range checking is off, |
| 197 | the extra bytes won't be missed terribly, but if range checking is on |
| 198 | and we used a larger request, a whole extra 4096 bytes would be |
| 199 | allocated. |
| 200 | |
| 201 | These number are irrelevant to the new GNU malloc. I suspect it is |
| 202 | less sensitive to the size of the request. */ |
| 203 | int extra = ((((12 + DEFAULT_ROUNDING - 1) & ~(DEFAULT_ROUNDING - 1)) |
| 204 | + 4 + DEFAULT_ROUNDING - 1) |
| 205 | & ~(DEFAULT_ROUNDING - 1)); |
| 206 | size = 4096 - extra; |
| 207 | } |
| 208 | |
SZEDER Gábor | 764473d | 2019-01-17 02:29:09 +0100 | [diff] [blame] | 209 | h->chunkfun.extra = (struct _obstack_chunk * (*)(void *,long)) chunkfun; |
| 210 | h->freefun.extra = (void (*) (void *, struct _obstack_chunk *)) freefun; |
| 211 | |
Fredrik Kuivinen | e831171 | 2011-08-21 00:40:40 +0200 | [diff] [blame] | 212 | h->chunk_size = size; |
| 213 | h->alignment_mask = alignment - 1; |
| 214 | h->extra_arg = arg; |
| 215 | h->use_extra_arg = 1; |
| 216 | |
| 217 | chunk = h->chunk = CALL_CHUNKFUN (h, h -> chunk_size); |
| 218 | if (!chunk) |
| 219 | (*obstack_alloc_failed_handler) (); |
| 220 | h->next_free = h->object_base = __PTR_ALIGN ((char *) chunk, chunk->contents, |
| 221 | alignment - 1); |
| 222 | h->chunk_limit = chunk->limit |
| 223 | = (char *) chunk + h->chunk_size; |
Ramsay Jones | 3254310 | 2011-09-11 20:26:53 +0100 | [diff] [blame] | 224 | chunk->prev = NULL; |
Fredrik Kuivinen | e831171 | 2011-08-21 00:40:40 +0200 | [diff] [blame] | 225 | /* The initial chunk now contains no empty object. */ |
| 226 | h->maybe_empty_object = 0; |
| 227 | h->alloc_failed = 0; |
| 228 | return 1; |
| 229 | } |
| 230 | |
| 231 | /* Allocate a new current chunk for the obstack *H |
| 232 | on the assumption that LENGTH bytes need to be added |
| 233 | to the current object, or a new object of length LENGTH allocated. |
| 234 | Copies any partial object from the end of the old chunk |
| 235 | to the beginning of the new one. */ |
| 236 | |
| 237 | void |
| 238 | _obstack_newchunk (struct obstack *h, int length) |
| 239 | { |
| 240 | register struct _obstack_chunk *old_chunk = h->chunk; |
| 241 | register struct _obstack_chunk *new_chunk; |
| 242 | register long new_size; |
| 243 | register long obj_size = h->next_free - h->object_base; |
| 244 | register long i; |
| 245 | long already; |
| 246 | char *object_base; |
| 247 | |
| 248 | /* Compute size for new chunk. */ |
| 249 | new_size = (obj_size + length) + (obj_size >> 3) + h->alignment_mask + 100; |
| 250 | if (new_size < h->chunk_size) |
| 251 | new_size = h->chunk_size; |
| 252 | |
| 253 | /* Allocate and initialize the new chunk. */ |
| 254 | new_chunk = CALL_CHUNKFUN (h, new_size); |
| 255 | if (!new_chunk) |
| 256 | (*obstack_alloc_failed_handler) (); |
| 257 | h->chunk = new_chunk; |
| 258 | new_chunk->prev = old_chunk; |
| 259 | new_chunk->limit = h->chunk_limit = (char *) new_chunk + new_size; |
| 260 | |
| 261 | /* Compute an aligned object_base in the new chunk */ |
| 262 | object_base = |
| 263 | __PTR_ALIGN ((char *) new_chunk, new_chunk->contents, h->alignment_mask); |
| 264 | |
| 265 | /* Move the existing object to the new chunk. |
| 266 | Word at a time is fast and is safe if the object |
| 267 | is sufficiently aligned. */ |
| 268 | if (h->alignment_mask + 1 >= DEFAULT_ALIGNMENT) |
| 269 | { |
| 270 | for (i = obj_size / sizeof (COPYING_UNIT) - 1; |
| 271 | i >= 0; i--) |
| 272 | ((COPYING_UNIT *)object_base)[i] |
| 273 | = ((COPYING_UNIT *)h->object_base)[i]; |
| 274 | /* We used to copy the odd few remaining bytes as one extra COPYING_UNIT, |
| 275 | but that can cross a page boundary on a machine |
| 276 | which does not do strict alignment for COPYING_UNITS. */ |
| 277 | already = obj_size / sizeof (COPYING_UNIT) * sizeof (COPYING_UNIT); |
| 278 | } |
| 279 | else |
| 280 | already = 0; |
| 281 | /* Copy remaining bytes one by one. */ |
| 282 | for (i = already; i < obj_size; i++) |
| 283 | object_base[i] = h->object_base[i]; |
| 284 | |
| 285 | /* If the object just copied was the only data in OLD_CHUNK, |
| 286 | free that chunk and remove it from the chain. |
| 287 | But not if that chunk might contain an empty object. */ |
| 288 | if (! h->maybe_empty_object |
| 289 | && (h->object_base |
| 290 | == __PTR_ALIGN ((char *) old_chunk, old_chunk->contents, |
| 291 | h->alignment_mask))) |
| 292 | { |
| 293 | new_chunk->prev = old_chunk->prev; |
| 294 | CALL_FREEFUN (h, old_chunk); |
| 295 | } |
| 296 | |
| 297 | h->object_base = object_base; |
| 298 | h->next_free = h->object_base + obj_size; |
| 299 | /* The new chunk certainly contains no empty object yet. */ |
| 300 | h->maybe_empty_object = 0; |
| 301 | } |
| 302 | # ifdef _LIBC |
| 303 | libc_hidden_def (_obstack_newchunk) |
| 304 | # endif |
| 305 | |
| 306 | /* Return nonzero if object OBJ has been allocated from obstack H. |
| 307 | This is here for debugging. |
| 308 | If you use it in a program, you are probably losing. */ |
| 309 | |
| 310 | /* Suppress -Wmissing-prototypes warning. We don't want to declare this in |
| 311 | obstack.h because it is just for debugging. */ |
| 312 | int _obstack_allocated_p (struct obstack *h, void *obj); |
| 313 | |
| 314 | int |
| 315 | _obstack_allocated_p (struct obstack *h, void *obj) |
| 316 | { |
| 317 | register struct _obstack_chunk *lp; /* below addr of any objects in this chunk */ |
| 318 | register struct _obstack_chunk *plp; /* point to previous chunk if any */ |
| 319 | |
| 320 | lp = (h)->chunk; |
| 321 | /* We use >= rather than > since the object cannot be exactly at |
| 322 | the beginning of the chunk but might be an empty object exactly |
| 323 | at the end of an adjacent chunk. */ |
Ramsay Jones | 3254310 | 2011-09-11 20:26:53 +0100 | [diff] [blame] | 324 | while (lp != NULL && ((void *) lp >= obj || (void *) (lp)->limit < obj)) |
Fredrik Kuivinen | e831171 | 2011-08-21 00:40:40 +0200 | [diff] [blame] | 325 | { |
| 326 | plp = lp->prev; |
| 327 | lp = plp; |
| 328 | } |
Ramsay Jones | 3254310 | 2011-09-11 20:26:53 +0100 | [diff] [blame] | 329 | return lp != NULL; |
Fredrik Kuivinen | e831171 | 2011-08-21 00:40:40 +0200 | [diff] [blame] | 330 | } |
| 331 | |
| 332 | /* Free objects in obstack H, including OBJ and everything allocate |
| 333 | more recently than OBJ. If OBJ is zero, free everything in H. */ |
| 334 | |
| 335 | # undef obstack_free |
| 336 | |
| 337 | void |
| 338 | obstack_free (struct obstack *h, void *obj) |
| 339 | { |
| 340 | register struct _obstack_chunk *lp; /* below addr of any objects in this chunk */ |
| 341 | register struct _obstack_chunk *plp; /* point to previous chunk if any */ |
| 342 | |
| 343 | lp = h->chunk; |
| 344 | /* We use >= because there cannot be an object at the beginning of a chunk. |
| 345 | But there can be an empty object at that address |
| 346 | at the end of another chunk. */ |
Ramsay Jones | 3254310 | 2011-09-11 20:26:53 +0100 | [diff] [blame] | 347 | while (lp != NULL && ((void *) lp >= obj || (void *) (lp)->limit < obj)) |
Fredrik Kuivinen | e831171 | 2011-08-21 00:40:40 +0200 | [diff] [blame] | 348 | { |
| 349 | plp = lp->prev; |
| 350 | CALL_FREEFUN (h, lp); |
| 351 | lp = plp; |
| 352 | /* If we switch chunks, we can't tell whether the new current |
| 353 | chunk contains an empty object, so assume that it may. */ |
| 354 | h->maybe_empty_object = 1; |
| 355 | } |
| 356 | if (lp) |
| 357 | { |
| 358 | h->object_base = h->next_free = (char *) (obj); |
| 359 | h->chunk_limit = lp->limit; |
| 360 | h->chunk = lp; |
| 361 | } |
Ramsay Jones | 3254310 | 2011-09-11 20:26:53 +0100 | [diff] [blame] | 362 | else if (obj != NULL) |
Fredrik Kuivinen | e831171 | 2011-08-21 00:40:40 +0200 | [diff] [blame] | 363 | /* obj is not in any of the chunks! */ |
| 364 | abort (); |
| 365 | } |
| 366 | |
| 367 | # ifdef _LIBC |
| 368 | /* Older versions of libc used a function _obstack_free intended to be |
| 369 | called by non-GCC compilers. */ |
| 370 | strong_alias (obstack_free, _obstack_free) |
| 371 | # endif |
| 372 | |
| 373 | int |
| 374 | _obstack_memory_used (struct obstack *h) |
| 375 | { |
| 376 | register struct _obstack_chunk* lp; |
| 377 | register int nbytes = 0; |
| 378 | |
Ramsay Jones | 3254310 | 2011-09-11 20:26:53 +0100 | [diff] [blame] | 379 | for (lp = h->chunk; lp != NULL; lp = lp->prev) |
Fredrik Kuivinen | e831171 | 2011-08-21 00:40:40 +0200 | [diff] [blame] | 380 | { |
| 381 | nbytes += lp->limit - (char *) lp; |
| 382 | } |
| 383 | return nbytes; |
| 384 | } |
| 385 | |
Fredrik Kuivinen | e831171 | 2011-08-21 00:40:40 +0200 | [diff] [blame] | 386 | # ifdef _LIBC |
| 387 | # include <libio/iolibio.h> |
| 388 | # endif |
| 389 | |
| 390 | # ifndef __attribute__ |
| 391 | /* This feature is available in gcc versions 2.5 and later. */ |
| 392 | # if __GNUC__ < 2 || (__GNUC__ == 2 && __GNUC_MINOR__ < 5) |
| 393 | # define __attribute__(Spec) /* empty */ |
| 394 | # endif |
| 395 | # endif |
| 396 | |
| 397 | static void |
Fredrik Kuivinen | e831171 | 2011-08-21 00:40:40 +0200 | [diff] [blame] | 398 | print_and_abort (void) |
| 399 | { |
| 400 | /* Don't change any of these strings. Yes, it would be possible to add |
| 401 | the newline to the string and use fputs or so. But this must not |
| 402 | happen because the "memory exhausted" message appears in other places |
| 403 | like this and the translation should be reused instead of creating |
| 404 | a very similar string which requires a separate translation. */ |
| 405 | # ifdef _LIBC |
| 406 | (void) __fxprintf (NULL, "%s\n", _("memory exhausted")); |
| 407 | # else |
| 408 | fprintf (stderr, "%s\n", _("memory exhausted")); |
| 409 | # endif |
Fredrik Kuivinen | d190a08 | 2011-08-28 22:08:46 +0200 | [diff] [blame] | 410 | exit (1); |
Fredrik Kuivinen | e831171 | 2011-08-21 00:40:40 +0200 | [diff] [blame] | 411 | } |
| 412 | |
| 413 | #endif /* !ELIDE_CODE */ |