* generic/tclIO.c (CopyData): [Bug 2895565]. Dropped bogosity

	* tests/io.test: which used the number of _written_ bytes or
	character to update the counters for the read bytes/characters.
	New test io-53.11. This is a backward port from the 8.5 branch.

3 files changed, 52 insertions, 7 deletions

diff --git a/ChangeLog b/ChangeLog
index aa1f3ac..40bda77 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,10 @@
+2009-11-12  Andreas Kupries  <andreask@activestate.com>
+
+	* generic/tclIO.c (CopyData): [Bug 2895565]. Dropped bogosity
+	* tests/io.test: which used the number of _written_ bytes or
+	character to update the counters for the read bytes/characters.
+	New test io-53.11. This is a backward port from the 8.5 branch.
+
 2009-11-10  Pat Thoyts  <patthoyts@users.sourceforge.net>
 
 	* tests/fCmd.test:     Fixed a number of issues for Vista
@@ -11,7 +18,7 @@
 
 2009-11-10  Andreas Kupries  <andreask@activestate.com>
 
-	* generic/tclObj.c: Plus memory leak in TclContinuationsEnter().
+	* generic/tclObj.c: Plug memory leak in TclContinuationsEnter().
 	[Bug 2895323]. Backport from Tcl 8.5 branch, change by Don Porter.
 
 2009-11-09  Andreas Kupries  <andreask@activestate.com>
diff --git a/generic/tclIO.c b/generic/tclIO.c
index 11cb205..c6d5c36 100644
--- a/generic/tclIO.c
+++ b/generic/tclIO.c
@@ -10,7 +10,7 @@
  * See the file "license.terms" for information on usage and redistribution
  * of this file, and for a DISCLAIMER OF ALL WARRANTIES.
  *
- * RCS: @(#) $Id: tclIO.c,v 1.61.2.33 2009/10/23 19:08:45 andreas_kupries Exp $
+ * RCS: @(#) $Id: tclIO.c,v 1.61.2.34 2009/11/12 17:41:30 andreas_kupries Exp $
  */
 
 #include "tclInt.h"
@@ -7936,10 +7936,17 @@ CopyData(csPtr, mask)
 	    sizeb = DoWriteChars(outStatePtr->topChanPtr, buffer, sizeb);
 	}
 
-	if (inBinary || sameEncoding) {
-	    /* Both read and write counted bytes */
-	    size = sizeb;
-	} /* else : Read counted characters, write counted bytes, i.e. size != sizeb */
+	/*
+	 * [Bug 2895565]. At this point 'size' still contains the number of
+	 * bytes or characters which have been read. We keep this to later to
+	 * update the totals and toRead information, see marker (UP) below. We
+	 * must not overwrite it with 'sizeb', which is the number of written
+	 * bytes or characters, and both EOL translation and encoding
+	 * conversion may have changed this number unpredictably in relation
+	 * to 'size' (It can be smaller or larger, in the latter case able to
+	 * drive toRead below -1, causing infinite looping). Completely
+	 * unsuitable for updating totals and toRead.
+	 */
 
 	if (sizeb < 0) {
 	    writeError:
diff --git a/tests/io.test b/tests/io.test
index 1a0f72e..9c94864 100644
--- a/tests/io.test
+++ b/tests/io.test
@@ -13,7 +13,7 @@
 # See the file "license.terms" for information on usage and redistribution
 # of this file, and for a DISCLAIMER OF ALL WARRANTIES.
 #
-# RCS: @(#) $Id: io.test,v 1.40.2.23 2008/06/20 16:49:11 dgp Exp $
+# RCS: @(#) $Id: io.test,v 1.40.2.24 2009/11/12 17:41:31 andreas_kupries Exp $
 
 if {[catch {package require tcltest 2}]} {
     puts stderr "Skipping tests in [info script].  tcltest 2 required."
@@ -7158,6 +7158,37 @@ test io-53.10 {Bug 1350564, multi-directional fcopy} -setup {
     removeFile err
     catch {unset ::forever}
 } -result {AB BA}
+test io-53.11 {Bug 2895565} -setup {
+    set in [makeFile {} in]
+    set f [open $in w]
+    fconfigure $f -encoding utf-8 -translation binary
+    puts -nonewline $f [string repeat "Ho hum\n" 11]
+    close $f
+    set inChan [open $in r]
+    fconfigure $inChan -translation binary
+    set out [makeFile {} out]
+    set outChan [open $out w]
+    fconfigure $outChan -encoding cp1252 -translation crlf
+    proc CopyDone {bytes args} {
+	variable done
+	if {[llength $args]} {
+	    set done "Error: '[lindex $args 0]' after $bytes bytes copied"
+	} else {
+	    set done "$bytes bytes copied"
+	}
+    }
+} -body {
+    variable done
+    after 2000 [list set [namespace which -variable done] timeout]
+    fcopy $inChan $outChan -size 40 -command [namespace which CopyDone]
+    vwait [namespace which -variable done]
+    set done
+} -cleanup {
+    close $outChan
+    close $inChan
+    removeFile out
+    removeFile in
+} -result {40 bytes copied}
 
 test io-54.1 {Recursive channel events} {socket fileevent} {
     # This test checks to see if file events are delivered during recursive