Changes to m4/lib/obstack.c [branch-1_4]

[Gary V . Vaughan]

Index: m4/lib/obstack.c
diff -u /dev/null m4/lib/obstack.c:1.1.1.1.2.1
--- /dev/null   Sun May  1 11:54:14 2005
+++ m4/lib/obstack.c    Sun May  1 11:54:12 2005
@@ -0,0 +1,489 @@
+/* obstack.c - subroutines used implicitly by object stack macros
+
+   Copyright (C) 1988, 1989, 1990, 1991, 1992, 1993, 1994
+   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 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, write to the Free Software
+   Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
+   02110-1301  USA
+*/
+
+#include "obstack.h"
+
+/* This is just to get __GNU_LIBRARY__ defined.  */
+#include <stdio.h>
+
+/* Comment out all this code if we are using the GNU C Library, and are not
+   actually compiling the library itself.  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.  */
+
+#if defined (_LIBC) || !defined (__GNU_LIBRARY__)
+
+
+#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)) \
+   : (*(h)->chunkfun) ((size)))
+
+#define CALL_FREEFUN(h, old_chunk) \
+  do { \
+    if ((h) -> use_extra_arg) \
+      (*(h)->freefun) ((h)->extra_arg, (old_chunk)); \
+    else \
+      (*(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 /* _LIBC or not __GNU_LIBRARY__.  */