+/* obstack.c - subroutines used implicitly by object stack macros
+ Copyright (C) 1988 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 1, 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"
+
+#ifdef __STDC__
+#define POINTER void *
+#else
+#define POINTER char *
+#endif
+
+/* Determine default alignment. */
+struct fooalign {char x; double d;};
+#define DEFAULT_ALIGNMENT ((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;
+\f
+/* 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. */
+
+void
+_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;
+
+ chunk = h->chunk = (*h->chunkfun) (h->chunk_size);
+ h->next_free = h->object_base = chunk->contents;
+ h->chunk_limit = chunk->limit
+ = (char *) chunk + h->chunk_size;
+ chunk->prev = 0;
+}
+
+/* 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 = h->chunk = (*h->chunkfun) (new_size);
+ 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. */
+ if (h->object_base == old_chunk->contents)
+ {
+ new_chunk->prev = old_chunk->prev;
+ (*h->freefun) (old_chunk);
+ }
+
+ h->object_base = new_chunk->contents;
+ h->next_free = h->object_base + obj_size;
+}
+
+/* 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. */
+
+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;
+ 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. */
+
+void
+#ifdef __STDC__
+#undef obstack_free
+obstack_free (struct obstack *h, POINTER obj)
+#else
+_obstack_free (h, obj)
+ struct obstack *h;
+ POINTER obj;
+#endif
+{
+ 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;
+ (*h->freefun) (lp);
+ lp = plp;
+ }
+ 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 ();
+}
+
+/* Let same .o link with output of gcc and other compilers. */
+
+#ifdef __STDC__
+void
+_obstack_free (h, obj)
+ struct obstack *h;
+ POINTER obj;
+{
+ obstack_free (h, obj);
+}
+#endif
+\f
+#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. */
+
+#ifdef __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 */
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