(DoWriteChars): special case for 1-byte channel write.

2 files changed, 12 insertions, 6 deletions

diff --git a/ChangeLog b/ChangeLog
index 1676faa..f3bd07f 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -2,6 +2,7 @@
 
 	* generic/tclIO.c (TclGetsObjBinary): add an efficient binary path
 	for [gets].
+	(DoWriteChars): special case for 1-byte channel write.
 
 2007-11-06  Miguel Sofer  <msofer@users.sf.net>
 
diff --git a/generic/tclIO.c b/generic/tclIO.c
index f157f7e..a7043bb 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 1.125 2007/11/07 19:18:03 hobbs Exp $
+ * RCS: @(#) $Id: tclIO.c,v 1.126 2007/11/07 23:52:21 hobbs Exp $
  */
 
 #include "tclInt.h"
@@ -3232,15 +3232,20 @@ DoWriteChars(
 	/*
 	 * Inefficient way to convert UTF-8 to byte-array, but the code
 	 * parallels the way it is done for objects.
+	 * Special case for 1-byte (used by eg [puts] for the \n) could
+	 * be extended to more efficient translation of the src string.
 	 */
 
-	Tcl_Obj *objPtr;
  	int result;
 
-	objPtr = Tcl_NewStringObj(src, len);
-	src = (char *) Tcl_GetByteArrayFromObj(objPtr, &len);
-	result = WriteBytes(chanPtr, src, len);
-	TclDecrRefCount(objPtr);
+	if ((len == 1) && (UCHAR(*src) < 0xC0)) {
+	    result = WriteBytes(chanPtr, src, len);
+	} else {
+	    Tcl_Obj *objPtr = Tcl_NewStringObj(src, len);
+	    src = (char *) Tcl_GetByteArrayFromObj(objPtr, &len);
+	    result = WriteBytes(chanPtr, src, len);
+	    TclDecrRefCount(objPtr);
+	}
 	return result;
     }
     return WriteChars(chanPtr, src, len);