[Bug 2946474] Consistently resume backgrounded flushes+closes when exiting.

3 files changed, 39 insertions, 2 deletions

diff --git a/ChangeLog b/ChangeLog
index 4126cee..6ebfce0 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,5 +1,10 @@
 2011-08-17  Alexandre Ferrieux  <ferrieux@users.sourceforge.net>
 
+	* generic/tclIO.c:  [Bug 2946474] Consistently resume backgrounded
+	* tests/ioCmd.test: flushes+closes when exiting.
+
+2011-08-17  Alexandre Ferrieux  <ferrieux@users.sourceforge.net>
+
 	* doc/interp.n: Document TIP 378's one-way-ness.
 	
 2011-08-17  Don Porter  <dgp@users.sourceforge.net>
diff --git a/generic/tclIO.c b/generic/tclIO.c
index 78c1dc0..a19fde8 100644
--- a/generic/tclIO.c
+++ b/generic/tclIO.c
@@ -414,8 +414,8 @@ TclFinalizeIOSubsystem(void)
 		statePtr != NULL;
 		statePtr = statePtr->nextCSPtr) {
 	    chanPtr = statePtr->topChanPtr;
-	    if (!GotFlag(statePtr, CHANNEL_INCLOSE | CHANNEL_CLOSED |
-		    CHANNEL_DEAD)) {
+            if (!GotFlag(statePtr, CHANNEL_INCLOSE | CHANNEL_CLOSED | CHANNEL_DEAD)
+                || GotFlag(statePtr, BG_FLUSH_SCHEDULED)) {
 		active = 1;
 		break;
 	    }
@@ -458,6 +458,7 @@ TclFinalizeIOSubsystem(void)
 		 * The refcount is greater than zero, so flush the channel.
 		 */
 
+                ResetFlag(statePtr, BG_FLUSH_SCHEDULED);
 		Tcl_Flush((Tcl_Channel) chanPtr);
 
 		/*
diff --git a/tests/ioCmd.test b/tests/ioCmd.test
index 82f83db..6536072 100644
--- a/tests/ioCmd.test
+++ b/tests/ioCmd.test
@@ -2592,9 +2592,40 @@ test iocmd.tf-24.15 {chan write, EAGAIN means that writing is not allowed at thi
 } -cleanup {
     rename foo {}
     unset res
+    update
 } -result {{write rc* ABC} {watch rc* write} {}} \
     -constraints {testchannel testthread}
 
+test iocmd.tf-24.16 {chan write, note the background flush setup by close due to the EAGAIN leaving data in buffers.} -match glob -setup {
+    set res {}
+    proc foo {args} {
+	oninit; onfinal; track
+	# Note: The EAGAIN signals that the channel cannot accept
+	# write requests right now, this in turn causes the IO core to
+	# request the generation of writable events (see expected
+	# result below, and compare to case 24.14 above).
+	error EAGAIN
+    }
+    set c [chan create {r w} foo]
+} -body {
+    notes [inthread $c {
+	note [puts -nonewline $c ABC ; flush $c]
+	close $c
+	notes
+    } c]
+    # Replace handler with all-tracking one which doesn't error.
+    # This will tell us if a write-due-flush is there.
+    proc foo {args} { note BG ; track }
+    # Flush (sic!) the event-queue to capture the write from a
+    # BG-flush.
+    update
+    set res
+} -cleanup {
+    rename foo {}
+    unset res
+} -result {{write rc* ABC} {watch rc* write} {} BG {write rc* ABC}} \
+    -constraints {testchannel testthread}
+
 # --- === *** ###########################
 # method cgetall