2001-07-18 Andreas Kupries <andreas_kupries@users.sourceforge.net>

	* generic/tclIO.c: Aftermath to [SF #427196]. Squash empty buffers
	  if they are smaller than the requested buffersize, to prevent
	  reusage of old buffers and to honor changes in the requested
	  buffersize made by the user.

2 files changed, 32 insertions, 1 deletions

diff --git a/ChangeLog b/ChangeLog
index 079bd62..e0e03fd 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,10 @@
+2001-07-18  Andreas Kupries <andreas_kupries@users.sourceforge.net>
+
+	* generic/tclIO.c: Aftermath to [SF #427196]. Squash empty buffers
+	  if they are smaller than the requested buffersize, to prevent
+	  reusage of old buffers and to honor changes in the requested
+	  buffersize made by the user.
+
 2001-07-17  Mo DeJong  <mdejong@redhat.com>
 
 	* win/tclWinFile.c (TclpReadlink): Add Cygwin specific definition
diff --git a/generic/tclIO.c b/generic/tclIO.c
index fe233ad..7bd0938 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 1.31 2001/07/17 17:53:43 andreas_kupries Exp $
+ * RCS: @(#) $Id: tclIO.c,v 1.32 2001/07/18 17:13:25 andreas_kupries Exp $
  */
 
 #include "tclInt.h"
@@ -1701,6 +1701,17 @@ RecycleBuffer(statePtr, bufPtr, mustDiscard)
     }
 
     /*
+     * Only save buffers which are at least as big as the requested
+     * buffersize for the channel. This is to honor dynamic changes
+     * of the buffersize made by the user.
+     */
+
+    if ((bufPtr->bufLength - BUFFER_PADDING) < statePtr->bufSize) {
+        ckfree((char *) bufPtr);
+        return;
+    }
+
+    /*
      * Only save buffers for the input queue if the channel is readable.
      */
     
@@ -4994,6 +5005,19 @@ GetInput(chanPtr)
     } else {
 	bufPtr = statePtr->saveInBufPtr;
 	statePtr->saveInBufPtr = NULL;
+
+	/*
+	 * Check the actual buffersize against the requested
+	 * buffersize. Buffers which are smaller than requested aare
+	 * squashed. This is done to honor dynamic changes of the
+	 * buffersize made by the user.
+	 */
+
+	if ((bufPtr != NULL) && ((bufPtr->bufLength - BUFFER_PADDING) < statePtr->bufSize)) {
+	  ckfree((char *) bufPtr);
+	  bufPtr = NULL;
+	}
+
 	if (bufPtr == NULL) {
 	    bufPtr = AllocChannelBuffer(statePtr->bufSize);
 	}