From 8b2b03ae112629d3aed9603f6dd7fe27746c2224 Mon Sep 17 00:00:00 2001
From: Frank Warmerdam <warmerdam@pobox.com>
Date: Fri, 24 Aug 2007 20:49:38 +0000
Subject: [PATCH] Write the tif_nextdiroff value instead of a fixed zero when
 writing directory contents to preserve the ability to rewrite directories in
 place, even in the middle of a directory chain.

---
 ChangeLog              | 7 ++++++-
 libtiff/tif_dirwrite.c | 6 +++---
 2 files changed, 9 insertions(+), 4 deletions(-)

diff --git a/ChangeLog b/ChangeLog
index ccc87336..32945c93 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,6 +1,11 @@
 2007-08-24  Frank Warmerdam  <warmerdam@pobox.com>
 
-	* tif_dirinfo.c: _TIFFMergeFields() now only merges in field
+	* tif_dirwrite.c: Write the tif_nextdiroff value instead of a fixed
+	zero when writing directory contents to preserve the ability to 
+	rewrite directories in place, even in the middle of a directory
+	chain.
+
+	* tif_dirinfo.c:  _TIFFMergeFields() now only merges in field
 	definitions that are missing.  Existing definitions are silently
 	ignored. 
 
diff --git a/libtiff/tif_dirwrite.c b/libtiff/tif_dirwrite.c
index 89aeb964..2eb9f74c 100644
--- a/libtiff/tif_dirwrite.c
+++ b/libtiff/tif_dirwrite.c
@@ -1,4 +1,4 @@
-/* $Id: tif_dirwrite.c,v 1.56 2007-07-10 11:52:02 dron Exp $ */
+/* $Id: tif_dirwrite.c,v 1.57 2007-08-24 20:49:38 fwarmerdam Exp $ */
 
 /*
  * Copyright (c) 1988-1997 Sam Leffler
@@ -781,7 +781,7 @@ TIFFWriteDirectorySec(TIFF* tif, int isimage, int imagedone, uint64* pdiroff)
 			n+=4;
 			o++;
 		}
-		*(uint32*)n=0;
+		*(uint32*)n = tif->tif_nextdiroff;
 	}
 	else
 	{
@@ -811,7 +811,7 @@ TIFFWriteDirectorySec(TIFF* tif, int isimage, int imagedone, uint64* pdiroff)
 			n+=8;
 			o++;
 		}
-		*(uint64*)n=0;
+		*(uint64*)n = tif->tif_nextdiroff;
 	}
 	_TIFFfree(dir);
 	dir=NULL;