summaryrefslogtreecommitdiffstats
diff options
context:
space:
mode:
-rw-r--r--ChangeLog10
-rw-r--r--tests/socket.test67
-rw-r--r--unix/tclUnixSock.c75
3 files changed, 126 insertions, 26 deletions
diff --git a/ChangeLog b/ChangeLog
index f6909b1..de04d25 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,13 @@
+2011-06-28 Reinhard Max <max@suse.de>
+
+ * unix/tclUnixSock.c (CreateClientSocket): Fix and simplify
+ posting of the writable fileevent at the end of an asynchronous
+ connection attempt. Improve comments for some of the trickery
+ around [socket -async]. [Bug 3325339]
+
+ * tests/socket.test: Adjust tests to the async code changes. Add
+ more tests for corner cases of async sockets.
+
2011-06-22 Andreas Kupries <andreask@activestate.com>
* library/platform/pkgIndex.tcl: Updated to platform 1.0.10. Added
diff --git a/tests/socket.test b/tests/socket.test
index 7f5c5c2..363f141 100644
--- a/tests/socket.test
+++ b/tests/socket.test
@@ -1751,21 +1751,23 @@ test socket-14.1 {[socket -async] fileevent while still connecting} \
}
set server [socket -server accept -myaddr 127.0.0.1 0]
set port [lindex [fconfigure $server -sockname] 2]
+ set x ""
} -body {
set client [socket -async localhost $port]
fileevent $client writable {
- lappend x [expr {[fconfigure $client -error] eq ""}]
+ lappend x [fconfigure $client -error]
}
- set after [after 1000 {set x timeout}]
- vwait x
- vwait x
- set x
+ set after [after 1000 {lappend x timeout}]
+ while {[llength $x] < 2 && "timeout" ni $x} {
+ vwait x
+ }
+ lsort $x; # we only want to see both events, the order doesn't matter
} -cleanup {
after cancel $after
close $server
close $client
unset x
- } -result {ok 1}
+ } -result {{} ok}
test socket-14.2 {[socket -async] fileevent connection refused} \
-constraints [list socket supported_any] \
-body {
@@ -1782,7 +1784,58 @@ test socket-14.2 {[socket -async] fileevent connection refused} \
close $client
unset x
} -result "connection refused"
-
+test socket-14.3 {[socket -async] fileevent host unreachable} \
+ -constraints [list socket supported_any] \
+ -body {
+ # address from rfc5737
+ set client [socket -async 192.0.2.42 [randport]]
+ fileevent $client writable {set x [fconfigure $client -error]}
+ set after [after 5000 {set x timeout}]
+ vwait x
+ if {$x eq "timeout"} {
+ append x ": [fconfigure $client -error]"
+ }
+ set x
+ } -cleanup {
+ after cancel $after
+ close $client
+ unset x
+ } -result "host is unreachable"
+test socket-14.4 {[socket -async] and both, readdable and writable fileevents} \
+ -constraints [list socket supported_any] \
+ -setup {
+ proc accept {s a p} {
+ puts $s bye
+ close $s
+ }
+ set server [socket -server accept -myaddr 127.0.0.1 0]
+ set port [lindex [fconfigure $server -sockname] 2]
+ set x ""
+ } -body {
+ set client [socket -async localhost $port]
+ fileevent $client writable {
+ lappend x [fconfigure $client -error]
+ fileevent $client writable {}
+ }
+ fileevent $client readable {lappend x [gets $client]}
+ set after [after 1000 {lappend x timeout}]
+ while {[llength $x] < 2 && "timeout" ni $x} {
+ vwait x
+ }
+ lsort $x
+ } -cleanup {
+ after cancel $after
+ close $client
+ close $server
+ } -result {{} bye}
+test socket-14.5 {[socket -async] which fails before any connect() can be made} \
+ -constraints [list socket supported_any] \
+ -body {
+ # addresses from rfc5737
+ socket -async -myaddr 192.0.2.42 198.51.100.42 [randport]
+ } \
+ -returnCodes 1 \
+ -result {couldn't open socket: cannot assign requested address}
::tcltest::cleanupTests
flush stdout
return
diff --git a/unix/tclUnixSock.c b/unix/tclUnixSock.c
index 5ace251..52b089c 100644
--- a/unix/tclUnixSock.c
+++ b/unix/tclUnixSock.c
@@ -858,6 +858,17 @@ TcpGetHandleProc(
return TCL_OK;
}
+/*
+ *----------------------------------------------------------------------
+ *
+ * TcpAsyncCallback --
+ *
+ * Called by the event handler that CreateClientSocket sets up
+ * internally for [socket -async] to get notified when the
+ * asyncronous connection attempt has succeeded or failed.
+ *
+ *----------------------------------------------------------------------
+ */
static void
TcpAsyncCallback(
ClientData clientData, /* The socket state. */
@@ -883,6 +894,18 @@ TcpAsyncCallback(
* Side effects:
* Opens a socket.
*
+ * Remarks:
+ * A single host name may resolve to more than one IP address, e.g. for
+ * an IPv4/IPv6 dual stack host. For handling asyncronously connecting
+ * sockets in the background for such hosts, this function can act as a
+ * coroutine. On the first call, it sets up the control variables for the
+ * two nested loops over the local and remote addresses. Once the first
+ * connection attempt is in progress, it sets up itself as a writable
+ * event handler for that socket, and returns. When the callback occurs,
+ * control is transferred to the "reenter" label, right after the initial
+ * return and the loops resume as if they had never been interrupted.
+ * For syncronously connecting sockets, the loops work the usual way.
+ *
*----------------------------------------------------------------------
*/
@@ -892,14 +915,14 @@ CreateClientSocket(
TcpState *state)
{
socklen_t optlen;
- int in_coro = (state->addr != NULL);
+ int async_callback = (state->addr != NULL);
int status;
int async = state->flags & TCP_ASYNC_CONNECT;
- if (in_coro) {
- goto coro_continue;
+ if (async_callback) {
+ goto reenter;
}
-
+
for (state->addr = state->addrlist; state->addr != NULL;
state->addr = state->addr->ai_next) {
@@ -976,12 +999,13 @@ CreateClientSocket(
TcpAsyncCallback, state);
return TCL_OK;
- coro_continue:
+ reenter:
Tcl_DeleteFileHandler(state->fds.fd);
/*
- * Read the error state from the socket, to see if the async
- * connection has succeeded or failed and store the status in
- * the socket state for later retrieval by [fconfigure -error]
+ * Read the error state from the socket to see if the async
+ * connection has succeeded or failed. As this clears the
+ * error condition, we cache the status in the socket state
+ * struct for later retrieval by [fconfigure -error].
*/
optlen = sizeof(int);
getsockopt(state->fds.fd, SOL_SOCKET, SO_ERROR,
@@ -996,22 +1020,35 @@ CreateClientSocket(
out:
- if (async) {
+ if (async_callback) {
+ /*
+ * An asynchonous connection has finally succeeded or failed.
+ */
CLEAR_BITS(state->flags, TCP_ASYNC_CONNECT);
TcpWatchProc(state, state->filehandlers);
TclUnixSetBlockingMode(state->fds.fd, TCL_MODE_BLOCKING);
- }
- if (status < 0) {
- if (in_coro) {
- Tcl_NotifyChannel(state->channel, TCL_WRITABLE);
- } else {
- if (interp != NULL) {
- Tcl_AppendResult(interp, "couldn't open socket: ",
- Tcl_PosixError(interp), NULL);
- }
- return TCL_ERROR;
+ /*
+ * We need to forward the writable event that brought us here, bcasue
+ * upon reading of getsockopt(SO_ERROR), at least some OSes clear the
+ * writable state from the socket, and so a subsequent select() on
+ * behalf of a script level [fileevent] would not fire. It doesn't
+ * hurt that this is also called in the successful case and will save
+ * the event mechanism one roundtrip through select().
+ */
+ Tcl_NotifyChannel(state->channel, TCL_WRITABLE);
+
+ } else if (status != 0) {
+ /*
+ * Failure for either a synchronous connection, or an async one that
+ * failed before it could enter background mode, e.g. because an
+ * invalid -myaddr was given.
+ */
+ if (interp != NULL) {
+ Tcl_AppendResult(interp, "couldn't open socket: ",
+ Tcl_PosixError(interp), NULL);
}
+ return TCL_ERROR;
}
return TCL_OK;
}