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Diffstat (limited to 'lib/obstack.c')
| -rw-r--r-- | lib/obstack.c | 428 |
1 files changed, 428 insertions, 0 deletions
diff --git a/lib/obstack.c b/lib/obstack.c new file mode 100644 index 0000000..f31a2e9 --- /dev/null +++ b/lib/obstack.c @@ -0,0 +1,428 @@ +/* obstack.c - subroutines used implicitly by object stack macros + + Copyright (C) 1988-1994, 1996-2006, 2009-2011 Free Software Foundation, Inc. + + This program is free software: you can redistribute it and/or modify + it under the terms of the GNU General Public License as published by + the Free Software Foundation; either version 3 of the License, or + (at your option) any later version. + + This program is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + GNU General Public License for more details. + + You should have received a copy of the GNU General Public License + along with this program. If not, see <http://www.gnu.org/licenses/>. */ + +#ifdef _LIBC +# include <obstack.h> +# include <shlib-compat.h> +#else +# include <config.h> +# include "obstack.h" +#endif + +/* NOTE BEFORE MODIFYING THIS FILE: This version number must be + incremented whenever callers compiled using an old obstack.h can no + longer properly call the functions in this obstack.c. */ +#define OBSTACK_INTERFACE_VERSION 1 + +/* Comment out all this code if we are using the GNU C Library, and are not + actually compiling the library itself, and the installed library + supports the same library interface we do. This code is part of the GNU + C Library, but also included in many other GNU distributions. Compiling + and linking in this code is a waste when using the GNU C library + (especially if it is a shared library). Rather than having every GNU + program understand `configure --with-gnu-libc' and omit the object + files, it is simpler to just do this in the source for each such file. */ + +#include <stdio.h> /* Random thing to get __GNU_LIBRARY__. */ +#if !defined _LIBC && defined __GNU_LIBRARY__ && __GNU_LIBRARY__ > 1 +# include <gnu-versions.h> +# if _GNU_OBSTACK_INTERFACE_VERSION == OBSTACK_INTERFACE_VERSION +# define ELIDE_CODE +# endif +#endif + +#include <stddef.h> + +#ifndef ELIDE_CODE + +# include <stdint.h> + +/* Determine default alignment. */ +union fooround +{ + uintmax_t i; + long double d; + void *p; +}; +struct fooalign +{ + char c; + union fooround u; +}; +/* If malloc were really smart, it would round addresses to DEFAULT_ALIGNMENT. + But in fact it might be less smart and round addresses to as much as + DEFAULT_ROUNDING. So we prepare for it to do that. */ +enum + { + DEFAULT_ALIGNMENT = offsetof (struct fooalign, u), + DEFAULT_ROUNDING = sizeof (union fooround) + }; + +/* When we copy a long block of data, this is the unit to do it with. + On some machines, copying successive ints does not work; + in such a case, redefine COPYING_UNIT to `long' (if that works) + or `char' as a last resort. */ +# ifndef COPYING_UNIT +# define COPYING_UNIT int +# endif + + +/* The functions allocating more room by calling `obstack_chunk_alloc' + jump to the handler pointed to by `obstack_alloc_failed_handler'. + This can be set to a user defined function which should either + abort gracefully or use longjump - but shouldn't return. This + variable by default points to the internal function + `print_and_abort'. */ +static void print_and_abort (void); +void (*obstack_alloc_failed_handler) (void) = print_and_abort; + +/* Exit value used when `print_and_abort' is used. */ +# include <stdlib.h> +# ifdef _LIBC +int obstack_exit_failure = EXIT_FAILURE; +# else +# include "exitfail.h" +# define obstack_exit_failure exit_failure +# endif + +# ifdef _LIBC +# if SHLIB_COMPAT (libc, GLIBC_2_0, GLIBC_2_3_4) +/* A looong time ago (before 1994, anyway; we're not sure) this global variable + was used by non-GNU-C macros to avoid multiple evaluation. The GNU C + library still exports it because somebody might use it. */ +struct obstack *_obstack_compat; +compat_symbol (libc, _obstack_compat, _obstack, GLIBC_2_0); +# endif +# endif + +/* Define a macro that either calls functions with the traditional malloc/free + calling interface, or calls functions with the mmalloc/mfree interface + (that adds an extra first argument), based on the state of use_extra_arg. + For free, do not use ?:, since some compilers, like the MIPS compilers, + do not allow (expr) ? void : void. */ + +# define CALL_CHUNKFUN(h, size) \ + (((h) -> use_extra_arg) \ + ? (*(h)->chunkfun) ((h)->extra_arg, (size)) \ + : (*(struct _obstack_chunk *(*) (long)) (h)->chunkfun) ((size))) + +# define CALL_FREEFUN(h, old_chunk) \ + do { \ + if ((h) -> use_extra_arg) \ + (*(h)->freefun) ((h)->extra_arg, (old_chunk)); \ + else \ + (*(void (*) (void *)) (h)->freefun) ((old_chunk)); \ + } while (0) + + +/* Initialize an obstack H for use. Specify chunk size SIZE (0 means default). + Objects start on multiples of ALIGNMENT (0 means use default). + CHUNKFUN is the function to use to allocate chunks, + and FREEFUN the function to free them. + + Return nonzero if successful, calls obstack_alloc_failed_handler if + allocation fails. */ + +int +_obstack_begin (struct obstack *h, + int size, int alignment, + void *(*chunkfun) (long), + void (*freefun) (void *)) +{ + register struct _obstack_chunk *chunk; /* points to new chunk */ + + if (alignment == 0) + alignment = DEFAULT_ALIGNMENT; + if (size == 0) + /* Default size is what GNU malloc can fit in a 4096-byte block. */ + { + /* 12 is sizeof (mhead) and 4 is EXTRA from GNU malloc. + Use the values for range checking, because if range checking is off, + the extra bytes won't be missed terribly, but if range checking is on + and we used a larger request, a whole extra 4096 bytes would be + allocated. + + These number are irrelevant to the new GNU malloc. I suspect it is + less sensitive to the size of the request. */ + int extra = ((((12 + DEFAULT_ROUNDING - 1) & ~(DEFAULT_ROUNDING - 1)) + + 4 + DEFAULT_ROUNDING - 1) + & ~(DEFAULT_ROUNDING - 1)); + size = 4096 - extra; + } + + h->chunkfun = (struct _obstack_chunk * (*)(void *, long)) chunkfun; + h->freefun = (void (*) (void *, struct _obstack_chunk *)) freefun; + h->chunk_size = size; + h->alignment_mask = alignment - 1; + h->use_extra_arg = 0; + + chunk = h->chunk = CALL_CHUNKFUN (h, h -> chunk_size); + if (!chunk) + (*obstack_alloc_failed_handler) (); + h->next_free = h->object_base = __PTR_ALIGN ((char *) chunk, chunk->contents, + alignment - 1); + h->chunk_limit = chunk->limit + = (char *) chunk + h->chunk_size; + chunk->prev = 0; + /* The initial chunk now contains no empty object. */ + h->maybe_empty_object = 0; + h->alloc_failed = 0; + return 1; +} + +int +_obstack_begin_1 (struct obstack *h, int size, int alignment, + void *(*chunkfun) (void *, long), + void (*freefun) (void *, void *), + void *arg) +{ + register struct _obstack_chunk *chunk; /* points to new chunk */ + + if (alignment == 0) + alignment = DEFAULT_ALIGNMENT; + if (size == 0) + /* Default size is what GNU malloc can fit in a 4096-byte block. */ + { + /* 12 is sizeof (mhead) and 4 is EXTRA from GNU malloc. + Use the values for range checking, because if range checking is off, + the extra bytes won't be missed terribly, but if range checking is on + and we used a larger request, a whole extra 4096 bytes would be + allocated. + + These number are irrelevant to the new GNU malloc. I suspect it is + less sensitive to the size of the request. */ + int extra = ((((12 + DEFAULT_ROUNDING - 1) & ~(DEFAULT_ROUNDING - 1)) + + 4 + DEFAULT_ROUNDING - 1) + & ~(DEFAULT_ROUNDING - 1)); + size = 4096 - extra; + } + + h->chunkfun = (struct _obstack_chunk * (*)(void *,long)) chunkfun; + h->freefun = (void (*) (void *, struct _obstack_chunk *)) freefun; + h->chunk_size = size; + h->alignment_mask = alignment - 1; + h->extra_arg = arg; + h->use_extra_arg = 1; + + chunk = h->chunk = CALL_CHUNKFUN (h, h -> chunk_size); + if (!chunk) + (*obstack_alloc_failed_handler) (); + h->next_free = h->object_base = __PTR_ALIGN ((char *) chunk, chunk->contents, + alignment - 1); + h->chunk_limit = chunk->limit + = (char *) chunk + h->chunk_size; + chunk->prev = 0; + /* The initial chunk now contains no empty object. */ + h->maybe_empty_object = 0; + h->alloc_failed = 0; + return 1; +} + +/* Allocate a new current chunk for the obstack *H + on the assumption that LENGTH bytes need to be added + to the current object, or a new object of length LENGTH allocated. + Copies any partial object from the end of the old chunk + to the beginning of the new one. */ + +void +_obstack_newchunk (struct obstack *h, int length) +{ + register struct _obstack_chunk *old_chunk = h->chunk; + register struct _obstack_chunk *new_chunk; + register long new_size; + register long obj_size = h->next_free - h->object_base; + register long i; + long already; + char *object_base; + + /* Compute size for new chunk. */ + new_size = (obj_size + length) + (obj_size >> 3) + h->alignment_mask + 100; + if (new_size < h->chunk_size) + new_size = h->chunk_size; + + /* Allocate and initialize the new chunk. */ + new_chunk = CALL_CHUNKFUN (h, new_size); + if (!new_chunk) + (*obstack_alloc_failed_handler) (); + h->chunk = new_chunk; + new_chunk->prev = old_chunk; + new_chunk->limit = h->chunk_limit = (char *) new_chunk + new_size; + + /* Compute an aligned object_base in the new chunk */ + object_base = + __PTR_ALIGN ((char *) new_chunk, new_chunk->contents, h->alignment_mask); + + /* Move the existing object to the new chunk. + Word at a time is fast and is safe if the object + is sufficiently aligned. */ + if (h->alignment_mask + 1 >= DEFAULT_ALIGNMENT) + { + for (i = obj_size / sizeof (COPYING_UNIT) - 1; + i >= 0; i--) + ((COPYING_UNIT *)object_base)[i] + = ((COPYING_UNIT *)h->object_base)[i]; + /* We used to copy the odd few remaining bytes as one extra COPYING_UNIT, + but that can cross a page boundary on a machine + which does not do strict alignment for COPYING_UNITS. */ + already = obj_size / sizeof (COPYING_UNIT) * sizeof (COPYING_UNIT); + } + else + already = 0; + /* Copy remaining bytes one by one. */ + for (i = already; i < obj_size; i++) + object_base[i] = h->object_base[i]; + + /* If the object just copied was the only data in OLD_CHUNK, + free that chunk and remove it from the chain. + But not if that chunk might contain an empty object. */ + if (! h->maybe_empty_object + && (h->object_base + == __PTR_ALIGN ((char *) old_chunk, old_chunk->contents, + h->alignment_mask))) + { + new_chunk->prev = old_chunk->prev; + CALL_FREEFUN (h, old_chunk); + } + + h->object_base = object_base; + h->next_free = h->object_base + obj_size; + /* The new chunk certainly contains no empty object yet. */ + h->maybe_empty_object = 0; +} +# ifdef _LIBC +libc_hidden_def (_obstack_newchunk) +# endif + +/* Return nonzero if object OBJ has been allocated from obstack H. + This is here for debugging. + If you use it in a program, you are probably losing. */ + +/* Suppress -Wmissing-prototypes warning. We don't want to declare this in + obstack.h because it is just for debugging. */ +int _obstack_allocated_p (struct obstack *h, void *obj); + +int +_obstack_allocated_p (struct obstack *h, void *obj) +{ + register struct _obstack_chunk *lp; /* below addr of any objects in this chunk */ + register struct _obstack_chunk *plp; /* point to previous chunk if any */ + + lp = (h)->chunk; + /* We use >= rather than > since the object cannot be exactly at + the beginning of the chunk but might be an empty object exactly + at the end of an adjacent chunk. */ + while (lp != 0 && ((void *) lp >= obj || (void *) (lp)->limit < obj)) + { + plp = lp->prev; + lp = plp; + } + return lp != 0; +} + +/* Free objects in obstack H, including OBJ and everything allocate + more recently than OBJ. If OBJ is zero, free everything in H. */ + +# undef obstack_free + +void +__obstack_free (struct obstack *h, void *obj) +{ + register struct _obstack_chunk *lp; /* below addr of any objects in this chunk */ + register struct _obstack_chunk *plp; /* point to previous chunk if any */ + + lp = h->chunk; + /* We use >= because there cannot be an object at the beginning of a chunk. + But there can be an empty object at that address + at the end of another chunk. */ + while (lp != 0 && ((void *) lp >= obj || (void *) (lp)->limit < obj)) + { + plp = lp->prev; + CALL_FREEFUN (h, lp); + lp = plp; + /* If we switch chunks, we can't tell whether the new current + chunk contains an empty object, so assume that it may. */ + h->maybe_empty_object = 1; + } + if (lp) + { + h->object_base = h->next_free = (char *) (obj); + h->chunk_limit = lp->limit; + h->chunk = lp; + } + else if (obj != 0) + /* obj is not in any of the chunks! */ + abort (); +} + +# ifdef _LIBC +/* Older versions of libc used a function _obstack_free intended to be + called by non-GCC compilers. */ +strong_alias (obstack_free, _obstack_free) +# endif + +int +_obstack_memory_used (struct obstack *h) +{ + register struct _obstack_chunk* lp; + register int nbytes = 0; + + for (lp = h->chunk; lp != 0; lp = lp->prev) + { + nbytes += lp->limit - (char *) lp; + } + return nbytes; +} + +/* Define the error handler. */ +# ifdef _LIBC +# include <libintl.h> +# else +# include "gettext.h" +# endif +# ifndef _ +# define _(msgid) gettext (msgid) +# endif + +# ifdef _LIBC +# include <libio/iolibio.h> +# endif + +# ifndef __attribute__ +/* This feature is available in gcc versions 2.5 and later. */ +# if __GNUC__ < 2 || (__GNUC__ == 2 && __GNUC_MINOR__ < 5) +# define __attribute__(Spec) /* empty */ +# endif +# endif + +static void +__attribute__ ((noreturn)) +print_and_abort (void) +{ + /* Don't change any of these strings. Yes, it would be possible to add + the newline to the string and use fputs or so. But this must not + happen because the "memory exhausted" message appears in other places + like this and the translation should be reused instead of creating + a very similar string which requires a separate translation. */ +# ifdef _LIBC + (void) __fxprintf (NULL, "%s\n", _("memory exhausted")); +# else + fprintf (stderr, "%s\n", _("memory exhausted")); +# endif + exit (obstack_exit_failure); +} + +#endif /* !ELIDE_CODE */ |