From bc3bc9925bac8831b519bf551f870964ae737fe6 Mon Sep 17 00:00:00 2001
From: Frank Warmerdam <warmerdam@pobox.com>
Date: Fri, 18 Feb 2011 21:54:22 +0000
Subject: [PATCH] added a configure option to enable CHUNKY_STRIP_READ support
 (--enable-chunky-strip-read)

---
 ChangeLog               |  6 +++++-
 configure               | 45 ++++++++++++++++++++++++++++++++++++-----
 configure.ac            | 16 +++++++++++++++
 libtiff/tif_config.h.in |  3 +++
 4 files changed, 64 insertions(+), 6 deletions(-)

diff --git a/ChangeLog b/ChangeLog
index e3436fd9..33050ac8 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,5 +1,9 @@
 2011-02-18  Frank Warmerdam  <warmerdam@pobox.com>
 
+	* configure.ac, configure: Added support for --enable-chunky-strip-read
+	configure option to enable the experimental feature from a couple 
+	months ago for reading big strips in chunks. 
+
 	* configure.ac, tif_read.c, tif_readdir.c, tif_dir.h, tiffiop.h, 
 	tif_write.c, tif_print.c, tif_jpeg.c, tif_dirwrite.c, tif_write.c:
 	Implement optional support for deferring the load of strip/tile 
@@ -38,7 +42,7 @@
 
 	* libtiff/tif_jpeg.c: ensure that rawcc and rawcp are maintained
 	during JPEGPreDecode and JPEGDecode calls.  
-	* libtiff/tif_read.c: arger read ahead for CHUNKY_STRIP_READ_SUPPORT, 
+	* libtiff/tif_read.c: larger read ahead for CHUNKY_STRIP_READ_SUPPORT, 
 	as compression formats like JPEG keep 16 lines interleaved in a sense 
 	and might need to touch	quite a bit of data. 
 	
diff --git a/configure b/configure
index 6d91023b..2b589c82 100755
--- a/configure
+++ b/configure
@@ -784,7 +784,6 @@ enable_fast_install
 with_gnu_ld
 with_sysroot
 enable_libtool_lock
-with_gnu_ld
 enable_silent_rules
 enable_rpath
 enable_largefile
@@ -817,6 +816,8 @@ enable_cxx
 with_x
 enable_strip_chopping
 with_default_strip_size
+enable_defer_strile_load
+enable_chunky_strip_read
 enable_extrasample_as_alpha
 enable_check_ycbcr_subsampling
 '
@@ -829,12 +830,8 @@ LDFLAGS
 LIBS
 CPPFLAGS
 CPP
-CPPFLAGS
 CXX
 CXXFLAGS
-LDFLAGS
-LIBS
-CPPFLAGS
 CCC
 CXXCPP
 XMKMF'
@@ -1504,6 +1501,12 @@ Optional Features:
                           to convert single-strip uncompressed images to
                           mutiple strips of specified size to reduce memory
                           usage)
+  --enable-defer-strile-load
+                          enable deferred strip/tile offset/size loading
+                          (experimental)
+  --enable-chunky-strip-read
+                          enable reading large strips in chunks for
+                          TIFFReadScanline() (experimental)
   --disable-extrasample-as-alpha
                           the RGBA interface will treat a fourth sample with
                           no EXTRASAMPLE_ value as being ASSOCALPHA. Many
@@ -19683,6 +19686,38 @@ _ACEOF
 fi
 
 
+# Check whether --enable-defer-strile-load was given.
+if test "${enable_defer_strile_load+set}" = set; then :
+  enableval=$enable_defer_strile_load; HAVE_DEFER_STRILE_LOAD=$enableval
+else
+  HAVE_DEFER_STRILE_LOAD=no
+fi
+
+
+if test "$HAVE_DEFER_STRILE_LOAD" = "yes" ; then
+
+$as_echo "#define DEFER_STRILE_LOAD 1" >>confdefs.h
+
+
+fi
+
+
+# Check whether --enable-chunky-strip-read was given.
+if test "${enable_chunky_strip_read+set}" = set; then :
+  enableval=$enable_chunky_strip_read; HAVE_CHUNKY_STRIP_READ=$enableval
+else
+  HAVE_CHUNKY_STRIP_READ=no
+fi
+
+
+if test "$HAVE_CHUNKY_STRIP_READ" = "yes" ; then
+
+$as_echo "#define CHUNKY_STRIP_READ 1" >>confdefs.h
+
+
+fi
+
+
 $as_echo "#define SUBIFD_SUPPORT 1" >>confdefs.h
 
 
diff --git a/configure.ac b/configure.ac
index ed398a56..d39aa377 100644
--- a/configure.ac
+++ b/configure.ac
@@ -854,6 +854,22 @@ if test "$HAVE_DEFER_STRILE_LOAD" = "yes" ; then
 
 fi
 
+dnl ---------------------------------------------------------------------------
+dnl Check for support of CHUNKY_STRIP_READ_SUPPORT, a mechanism to allowing
+dnl reading large strips (usually one strip files) in chunks when using
+dnl TIFFReadScanline().  This is an experimental feature in libtiff 4.0.
+dnl ---------------------------------------------------------------------------
+
+AC_ARG_ENABLE(chunky-strip-read,
+	      AS_HELP_STRING([--enable-chunky-strip-read],
+			     [enable reading large strips in chunks for TIFFReadScanline() (experimental)]),
+	      [HAVE_CHUNKY_STRIP_READ=$enableval], [HAVE_CHUNKY_STRIP_READ=no])
+
+if test "$HAVE_CHUNKY_STRIP_READ" = "yes" ; then
+  AC_DEFINE(CHUNKY_STRIP_READ,1,[enable partial strip reading for large strips (experimental)])
+
+fi
+
 dnl ---------------------------------------------------------------------------
 dnl Default subifd support.
 dnl ---------------------------------------------------------------------------
diff --git a/libtiff/tif_config.h.in b/libtiff/tif_config.h.in
index 09a427cb..d13ece67 100644
--- a/libtiff/tif_config.h.in
+++ b/libtiff/tif_config.h.in
@@ -10,6 +10,9 @@
    lacking the tag (default enabled). */
 #undef CHECK_JPEG_YCBCR_SUBSAMPLING
 
+/* enable partial strip reading for large strips (experimental) */
+#undef CHUNKY_STRIP_READ
+
 /* Support C++ stream API (requires C++ compiler) */
 #undef CXX_SUPPORT