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Diffstat (limited to 'libiberty/obstack.c')
| -rw-r--r-- | libiberty/obstack.c | 514 |
1 files changed, 514 insertions, 0 deletions
diff --git a/libiberty/obstack.c b/libiberty/obstack.c new file mode 100644 index 00000000000..a6880caaa6c --- /dev/null +++ b/libiberty/obstack.c @@ -0,0 +1,514 @@ +/* obstack.c - subroutines used implicitly by object stack macros + Copyright (C) 1988, 89, 90, 91, 92, 93, 94, 95, 96 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 2, 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, write to the Free Software +Foundation, 675 Mass Ave, Cambridge, MA 02139, USA. */ + +#include "obstack.h" + +/* 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 + +/* CYGNUS LOCAL (not to be elided!) */ + +int +_obstack_memory_used (h) + 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; +} + +/* END CYGNUS LOCAL */ + +#ifndef ELIDE_CODE + + +#if defined (__STDC__) && __STDC__ +#define POINTER void * +#else +#define POINTER char * +#endif + +/* Determine default alignment. */ +struct fooalign {char x; double d;}; +#define DEFAULT_ALIGNMENT \ + ((PTR_INT_TYPE) ((char *) &((struct fooalign *) 0)->d - (char *) 0)) +/* 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. */ +union fooround {long x; double d;}; +#define 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 non-GNU-C macros copy the obstack into this global variable + to avoid multiple evaluation. */ + +struct obstack *_obstack; + +/* 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 *(*) ()) (h)->chunkfun) ((size))) + +#define CALL_FREEFUN(h, old_chunk) \ + do { \ + if ((h) -> use_extra_arg) \ + (*(h)->freefun) ((h)->extra_arg, (old_chunk)); \ + else \ + (*(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, zero if out of memory. + To recover from an out of memory error, + free up some memory, then call this again. */ + +int +_obstack_begin (h, size, alignment, chunkfun, freefun) + struct obstack *h; + int size; + int alignment; + POINTER (*chunkfun) (); + void (*freefun) (); +{ + 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 * (*)()) chunkfun; + h->freefun = 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) + { + h->alloc_failed = 1; + return 0; + } + h->alloc_failed = 0; + h->next_free = h->object_base = chunk->contents; + 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; + return 1; +} + +int +_obstack_begin_1 (h, size, alignment, chunkfun, freefun, arg) + struct obstack *h; + int size; + int alignment; + POINTER (*chunkfun) (); + void (*freefun) (); + POINTER 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 * (*)()) chunkfun; + h->freefun = 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) + { + h->alloc_failed = 1; + return 0; + } + h->alloc_failed = 0; + h->next_free = h->object_base = chunk->contents; + 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; + 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 (h, length) + struct obstack *h; + int length; +{ + register struct _obstack_chunk *old_chunk = h->chunk; + register struct _obstack_chunk *new_chunk; + register long new_size; + register int obj_size = h->next_free - h->object_base; + register int i; + int already; + + /* Compute size for new chunk. */ + new_size = (obj_size + length) + (obj_size >> 3) + 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) + { + h->alloc_failed = 1; + return; + } + h->alloc_failed = 0; + h->chunk = new_chunk; + new_chunk->prev = old_chunk; + new_chunk->limit = h->chunk_limit = (char *) new_chunk + new_size; + + /* 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 *)new_chunk->contents)[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++) + new_chunk->contents[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->object_base == old_chunk->contents && ! h->maybe_empty_object) + { + new_chunk->prev = old_chunk->prev; + CALL_FREEFUN (h, old_chunk); + } + + h->object_base = new_chunk->contents; + h->next_free = h->object_base + obj_size; + /* The new chunk certainly contains no empty object yet. */ + h->maybe_empty_object = 0; +} + +/* 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. */ + +#if defined (__STDC__) && __STDC__ +/* 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, POINTER obj); +#endif + +int +_obstack_allocated_p (h, obj) + struct obstack *h; + POINTER 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 && ((POINTER) lp >= obj || (POINTER) (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 + +/* This function has two names with identical definitions. + This is the first one, called from non-ANSI code. */ + +void +_obstack_free (h, obj) + struct obstack *h; + POINTER 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 && ((POINTER) lp >= obj || (POINTER) (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 (); +} + +/* This function is used from ANSI code. */ + +void +obstack_free (h, obj) + struct obstack *h; + POINTER 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 && ((POINTER) lp >= obj || (POINTER) (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 (); +} + +#if 0 +/* These are now turned off because the applications do not use it + and it uses bcopy via obstack_grow, which causes trouble on sysV. */ + +/* Now define the functional versions of the obstack macros. + Define them to simply use the corresponding macros to do the job. */ + +#if defined (__STDC__) && __STDC__ +/* These function definitions do not work with non-ANSI preprocessors; + they won't pass through the macro names in parentheses. */ + +/* The function names appear in parentheses in order to prevent + the macro-definitions of the names from being expanded there. */ + +POINTER (obstack_base) (obstack) + struct obstack *obstack; +{ + return obstack_base (obstack); +} + +POINTER (obstack_next_free) (obstack) + struct obstack *obstack; +{ + return obstack_next_free (obstack); +} + +int (obstack_object_size) (obstack) + struct obstack *obstack; +{ + return obstack_object_size (obstack); +} + +int (obstack_room) (obstack) + struct obstack *obstack; +{ + return obstack_room (obstack); +} + +void (obstack_grow) (obstack, pointer, length) + struct obstack *obstack; + POINTER pointer; + int length; +{ + obstack_grow (obstack, pointer, length); +} + +void (obstack_grow0) (obstack, pointer, length) + struct obstack *obstack; + POINTER pointer; + int length; +{ + obstack_grow0 (obstack, pointer, length); +} + +void (obstack_1grow) (obstack, character) + struct obstack *obstack; + int character; +{ + obstack_1grow (obstack, character); +} + +void (obstack_blank) (obstack, length) + struct obstack *obstack; + int length; +{ + obstack_blank (obstack, length); +} + +void (obstack_1grow_fast) (obstack, character) + struct obstack *obstack; + int character; +{ + obstack_1grow_fast (obstack, character); +} + +void (obstack_blank_fast) (obstack, length) + struct obstack *obstack; + int length; +{ + obstack_blank_fast (obstack, length); +} + +POINTER (obstack_finish) (obstack) + struct obstack *obstack; +{ + return obstack_finish (obstack); +} + +POINTER (obstack_alloc) (obstack, length) + struct obstack *obstack; + int length; +{ + return obstack_alloc (obstack, length); +} + +POINTER (obstack_copy) (obstack, pointer, length) + struct obstack *obstack; + POINTER pointer; + int length; +{ + return obstack_copy (obstack, pointer, length); +} + +POINTER (obstack_copy0) (obstack, pointer, length) + struct obstack *obstack; + POINTER pointer; + int length; +{ + return obstack_copy0 (obstack, pointer, length); +} + +#endif /* __STDC__ */ + +#endif /* 0 */ + +#endif /* !ELIDE_CODE */ |