--- /dev/null
+/* objalloc.h -- routines to allocate memory for objects
+ Copyright 1997 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, 675 Mass Ave, Cambridge, MA 02139, 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;
+ PTR chunks;
+};
+
+/* Work out the required alignment. */
+
+struct objalloc_align { char x; double d; };
+
+#if defined (__STDC__) && __STDC__
+#ifndef offsetof
+#include <stddef.h>
+#endif
+#define OBJALLOC_ALIGN \
+ ((ptrdiff_t) ((char *) &((struct objalloc_align *) 0)->d - (char *) 0))
+#else
+#define OBJALLOC_ALIGN \
+ ((long) ((char *) &((struct objalloc_align *) 0)->d - (char *) 0))
+#endif
+
+/* Create an objalloc structure. Returns NULL if malloc fails. */
+
+extern struct objalloc *objalloc_create PARAMS ((void));
+
+/* Allocate space from an objalloc structure. Returns NULL if malloc
+ fails. */
+
+extern PTR _objalloc_alloc PARAMS ((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, \
+ (PTR) (__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 PARAMS ((struct objalloc *));
+
+/* Free a block allocated by objalloc_alloc. This also frees all more
+ recently allocated blocks. */
+
+extern void objalloc_free_block PARAMS ((struct objalloc *, PTR));
+
+#endif /* OBJALLOC_H */
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