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Diffstat (limited to 'gcc-4.6/include/objalloc.h')
| -rw-r--r-- | gcc-4.6/include/objalloc.h | 115 |
1 files changed, 115 insertions, 0 deletions
diff --git a/gcc-4.6/include/objalloc.h b/gcc-4.6/include/objalloc.h new file mode 100644 index 000000000..36772d17b --- /dev/null +++ b/gcc-4.6/include/objalloc.h @@ -0,0 +1,115 @@ +/* objalloc.h -- routines to allocate memory for objects + Copyright 1997, 2001 Free Software Foundation, Inc. + Written by Ian Lance Taylor, Cygnus Solutions. + +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, 51 Franklin Street - Fifth Floor, +Boston, MA 02110-1301, USA. */ + +#ifndef OBJALLOC_H +#define OBJALLOC_H + +#include "ansidecl.h" + +/* These routines allocate space for an object. The assumption is + that the object will want to allocate space as it goes along, but + will never want to free any particular block. There is a function + to free a block, which also frees all more recently allocated + blocks. There is also a function to free all the allocated space. + + This is essentially a specialization of obstacks. The main + difference is that a block may not be allocated a bit at a time. + Another difference is that these routines are always built on top + of malloc, and always pass an malloc failure back to the caller, + unlike more recent versions of obstacks. */ + +/* This is what an objalloc structure looks like. Callers should not + refer to these fields, nor should they allocate these structure + themselves. Instead, they should only create them via + objalloc_init, and only access them via the functions and macros + listed below. The structure is only defined here so that we can + access it via macros. */ + +struct objalloc +{ + char *current_ptr; + unsigned int current_space; + void *chunks; +}; + +/* Work out the required alignment. */ + +struct objalloc_align { char x; double d; }; + +#if defined (__STDC__) && __STDC__ +#ifndef offsetof +#include <stddef.h> +#endif +#endif +#ifndef offsetof +#define offsetof(TYPE, MEMBER) ((unsigned long) &((TYPE *)0)->MEMBER) +#endif +#define OBJALLOC_ALIGN offsetof (struct objalloc_align, d) + +/* Create an objalloc structure. Returns NULL if malloc fails. */ + +extern struct objalloc *objalloc_create (void); + +/* Allocate space from an objalloc structure. Returns NULL if malloc + fails. */ + +extern void *_objalloc_alloc (struct objalloc *, unsigned long); + +/* The macro version of objalloc_alloc. We only define this if using + gcc, because otherwise we would have to evaluate the arguments + multiple times, or use a temporary field as obstack.h does. */ + +#if defined (__GNUC__) && defined (__STDC__) && __STDC__ + +/* NextStep 2.0 cc is really gcc 1.93 but it defines __GNUC__ = 2 and + does not implement __extension__. But that compiler doesn't define + __GNUC_MINOR__. */ +#if __GNUC__ < 2 || (__NeXT__ && !__GNUC_MINOR__) +#define __extension__ +#endif + +#define objalloc_alloc(o, l) \ + __extension__ \ + ({ struct objalloc *__o = (o); \ + unsigned long __len = (l); \ + if (__len == 0) \ + __len = 1; \ + __len = (__len + OBJALLOC_ALIGN - 1) &~ (OBJALLOC_ALIGN - 1); \ + (__len <= __o->current_space \ + ? (__o->current_ptr += __len, \ + __o->current_space -= __len, \ + (void *) (__o->current_ptr - __len)) \ + : _objalloc_alloc (__o, __len)); }) + +#else /* ! __GNUC__ */ + +#define objalloc_alloc(o, l) _objalloc_alloc ((o), (l)) + +#endif /* ! __GNUC__ */ + +/* Free an entire objalloc structure. */ + +extern void objalloc_free (struct objalloc *); + +/* Free a block allocated by objalloc_alloc. This also frees all more + recently allocated blocks. */ + +extern void objalloc_free_block (struct objalloc *, void *); + +#endif /* OBJALLOC_H */ |