* generic/tclZlib.c (ZlibTransformSetOption): [Bug 3517696]: Make

	flushing work correctly in a pushed compressing channel transform.

3 files changed, 39 insertions, 19 deletions

diff --git a/ChangeLog b/ChangeLog
index 06e7d7b..05631c6 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,7 +1,12 @@
+2012-04-15  Donal K. Fellows  <dkf@users.sf.net>
+
+	* generic/tclZlib.c (ZlibTransformSetOption): [Bug 3517696]: Make
+	flushing work correctly in a pushed compressing channel transform.
+
 2012-04-12  Jan Nijtmans  <nijtmans@users.sf.net>
 
-	* generic/tclInt.decls:      [Bug 3514475]: remove TclpGetTimeZone
-	* generic/tclIntDecls.h:     and TclpGetTZName
+	* generic/tclInt.decls:      [Bug 3514475]: Remove TclpGetTimeZone and
+	* generic/tclIntDecls.h:     TclpGetTZName
 	* generic/tclIntPlatDecls.h:
 	* generic/tclStubInit.c:
 	* unix/tclUnixTime.c:
@@ -9,20 +14,21 @@
 
 2012-04-11  Jan Nijtmans  <nijtmans@users.sf.net>
 
-	* win/tclWinInit.c:     [Bug 3448512]: clock scan "1958-01-01" fails only
-	* win/tcl.m4:           in debug compilation.
+	* win/tclWinInit.c:     [Bug 3448512]: clock scan "1958-01-01" fails
+	* win/tcl.m4:           only in debug compilation.
 	* win/configure:
 	* unix/tcl.m4:          Use NDEBUG consistantly meaning: no debugging.
 	* unix/configure:
 	* generic/tclBasic.c:
-	* library/dde/pkgIndex.tcl   Use [::tcl::pkgconfig get debug] in stead
+	* library/dde/pkgIndex.tcl   Use [::tcl::pkgconfig get debug] instead
 	* library/reg/pkgIndex.tcl   of [info exists ::tcl_platform(debug)]
 
 	***POTENTIAL INCOMPATIBILITY***
-	The variables $tcl_platform(debug) and $tcl_platform(threaded) no longer
-	exist. They don't belong in the tcl_platform array, were never documented,
-	disturbed the platform-1.1 test, $tcl_platform(debug) was only available
-	on Windows anyway, and TIP #59 provides a much better alternative.
+	The variables $tcl_platform(debug) and $tcl_platform(threaded) no
+	longer exist. They don't belong in the tcl_platform array, were never
+	documented, disturbed the platform-1.1 test, $tcl_platform(debug) was
+	only available on Windows anyway, and TIP #59 provides a much better
+	alternative.
 
 2012-04-10  Donal K. Fellows  <dkf@users.sf.net>
 
diff --git a/generic/tclZlib.c b/generic/tclZlib.c
index 81012dc..341f8e0 100644
--- a/generic/tclZlib.c
+++ b/generic/tclZlib.c
@@ -2495,27 +2495,29 @@ ZlibTransformSetOption(			/* not used */
 	 */
 
 	cd->outStream.avail_in = 0;
-	do {
+	while (1) {
 	    int e;
 
 	    cd->outStream.next_out = (Bytef *) cd->outBuffer;
 	    cd->outStream.avail_out = cd->outAllocated;
 
 	    e = deflate(&cd->outStream, flushType);
-	    if (e != Z_OK) {
+	    if (e == Z_BUF_ERROR) {
+		break;
+	    } else if (e != Z_OK) {
 		ConvertError(interp, e);
 		return TCL_ERROR;
+	    } else if (cd->outStream.avail_out == 0) {
+		break;
 	    }
 
-	    if (cd->outStream.avail_out > 0) {
-		if (Tcl_WriteRaw(cd->parent, cd->outBuffer,
-			PTR2INT(cd->outStream.next_out)) < 0) {
-		    Tcl_AppendResult(interp, "problem flushing channel: ",
-			    Tcl_PosixError(interp), NULL);
-		    return TCL_ERROR;
-		}
+	    if (Tcl_WriteRaw(cd->parent, cd->outBuffer,
+		    cd->outStream.next_out - (Bytef*)cd->outBuffer) < 0) {
+		Tcl_AppendResult(interp, "problem flushing channel: ",
+			Tcl_PosixError(interp), NULL);
+		return TCL_ERROR;
 	    }
-	} while (cd->outStream.avail_out > 0);
+	}
 	return TCL_OK;
     }
 
diff --git a/tests/zlib.test b/tests/zlib.test
index 236e6b6..3aaca29 100644
--- a/tests/zlib.test
+++ b/tests/zlib.test
@@ -156,6 +156,18 @@ test zlib-8.3 {zlib transformation and fileevent} -constraints zlib -setup {
     close $srv
     removeFile $file
 } -result 81920-->81920
+test zlib-8.4 {transformation and flushing: Bug 3517696} -setup {
+    set file [makeFile {} test.z]
+    set fd [open $file w]
+} -constraints zlib -body {
+    zlib push compress $fd
+    puts $fd "qwertyuiop"
+    fconfigure $fd -flush sync
+    puts $fd "qwertyuiop"
+} -cleanup {
+    catch {close $fd}
+    removeFile $file
+} -result {}
 
 test zlib-9.1 "check fcopy with push" -constraints zlib -setup {
     set sfile [makeFile {} testsrc.gz]