1 files changed, 16 insertions, 13 deletions

diff --git a/gl/xalloc.h b/gl/xalloc.h
index 17ab514..40dcf4b 100644
--- a/gl/xalloc.h
+++ b/gl/xalloc.h
@@ -1,12 +1,12 @@
 /* xalloc.h -- malloc with out-of-memory checking
 
    Copyright (C) 1990, 1991, 1992, 1993, 1994, 1995, 1996, 1997, 1998,
-   1999, 2000, 2003, 2004, 2006 Free Software Foundation, Inc.
+   1999, 2000, 2003, 2004, 2006, 2007, 2008 Free Software Foundation, Inc.
 
-   This program is free software; you can redistribute it and/or modify
+   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.
+   the Free Software Foundation; either version 3 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
@@ -14,8 +14,7 @@
    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.  */
+   along with this program.  If not, see <http://www.gnu.org/licenses/>.  */
 
 #ifndef XALLOC_H_
 # define XALLOC_H_
@@ -29,7 +28,7 @@ extern "C" {
 
 
 # ifndef __attribute__
-#  if __GNUC__ < 2 || (__GNUC__ == 2 && __GNUC_MINOR__ < 8) || __STRICT_ANSI__
+#  if __GNUC__ < 2 || (__GNUC__ == 2 && __GNUC_MINOR__ < 8)
 #   define __attribute__(x)
 #  endif
 # endif
@@ -139,10 +138,10 @@ xnrealloc (void *p, size_t n, size_t s)
    allocating an initial block with a nonzero size, or by allocating a
    larger block.
 
-   In the following implementation, nonzero sizes are doubled so that
-   repeated reallocations have O(N log N) overall cost rather than
-   O(N**2) cost, but the specification for this function does not
-   guarantee that sizes are doubled.
+   In the following implementation, nonzero sizes are increased by a
+   factor of approximately 1.5 so that repeated reallocations have
+   O(N) overall cost rather than O(N**2) cost, but the
+   specification for this function does not guarantee that rate.
 
    Here is an example of use:
 
@@ -204,9 +203,13 @@ x2nrealloc (void *p, size_t *pn, size_t s)
     }
   else
     {
-      if (((size_t) -1) / 2 / s < n)
+      /* Set N = ceil (1.5 * N) so that progress is made if N == 1.
+         Check for overflow, so that N * S stays in size_t range.
+         The check is slightly conservative, but an exact check isn't
+         worth the trouble.  */
+      if ((size_t) -1 / 3 * 2 / s <= n)
         xalloc_die ();
-      n *= 2;
+      n += (n + 1) / 2;
     }
 
   *pn = n;