Correct performance regression in a series of short binary reads from a

socket.  Many thanks to Eric Boudaillier for the report and testing support.

1 files changed, 7 insertions, 19 deletions

diff --git a/generic/tclIO.c b/generic/tclIO.c
index 4452ae9..93ac937 100644
--- a/generic/tclIO.c
+++ b/generic/tclIO.c
@@ -8853,34 +8853,22 @@ DoRead(
 	    break;
 	}
 
-	/* If there is no full buffer, attempt to create and/or fill one. */
-
-	while (!IsBufferFull(bufPtr)) {
-	    int code;
+	/*
+	 * If there is not enough data in the buffers to possibly
+	 * complete the read, then go get more.
+	 */
 
+	if (bufPtr == NULL || BytesLeft(bufPtr) < bytesToRead) {
 	moreData:
-	    code = GetInput(chanPtr);
-	    bufPtr = statePtr->inQueueHead;
-
-	    assert (bufPtr != NULL);
-
-	    if (GotFlag(statePtr, CHANNEL_EOF|CHANNEL_BLOCKED)) {
-		/* Further reads cannot do any more */
-		break;
-	    }
-	    
-	    if (code) {
+	    if (GetInput(chanPtr)) {
 		/* Read error */
 		UpdateInterest(chanPtr);
 		TclChannelRelease((Tcl_Channel)chanPtr);
 		return -1;
 	    }
-
-	    assert (IsBufferFull(bufPtr));
+	    bufPtr = statePtr->inQueueHead;
 	}
 
-	assert (bufPtr != NULL);
-
 	bytesRead = BytesLeft(bufPtr);
 	bytesWritten = bytesToRead;