From 8339de0c86602b9b9aeea1efb6245c4e47411884 Mon Sep 17 00:00:00 2001 From: dgp Date: Wed, 20 Aug 2014 17:50:41 +0000 Subject: Docs for Tcl_CreateChannelHandler() state that the registered handler proc will be called back with a mask value. "Mask is an integer mask indicating which of the requested conditions actually exists for the channel; it will contain ***a subset of the bits from the mask argument*** to Tcl_CreateChannelHandler when the handler was created." (emhpasis added). Tcl_NotifyChannel is not honoring this. It passes a mask value that may contain bits not in common with the mask argument to T_CCH(). This commit is a one-liner patch adding in the masking step to make things behave as documented. Thanks to apn for digging this out. (In combination with other questionable code, this led to a hang in test http-4.6 on Windows) Tcl_NotifyChannel() has had this error in all of recorded Tcl history. It's hard to imagine any code dependent on it though. If any exists, it can be revised to pass the mask value it truly needs to T_CCH() and end up with code suitable both before and after this change. If you concur, please merge to core-8-5-branch, and I'll take it from there. --- generic/tclIO.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/generic/tclIO.c b/generic/tclIO.c index afffeb8..4452ae9 100644 --- a/generic/tclIO.c +++ b/generic/tclIO.c @@ -7716,7 +7716,7 @@ Tcl_NotifyChannel( if ((chPtr->mask & mask) != 0) { nh.nextHandlerPtr = chPtr->nextPtr; - (*(chPtr->proc))(chPtr->clientData, mask); + (*(chPtr->proc))(chPtr->clientData, chPtr->mask & mask); chPtr = nh.nextHandlerPtr; } else { chPtr = chPtr->nextPtr; -- cgit v0.12