DEV: poll: make the connect() step an action as well

Now the connect() step becomes an action. It's still implicit before
any -c/-s but it allows the listener to close() before connect()
happens, showing the polling status for this condition:

  $ dev/poll/poll -v -l clo -c pol
  #### BEGIN ####
  cmd #1 stp #1: do_clo(3): ret=0
  cmd #2 stp #0: do_con(4): ret=-1 (Connection refused)
  cmd #2 stp #1: do_pol(4): ret=1 ev=0x14 (OUT HUP)
  #### END ####

which differs from a case where the server closes the just accepted
connection:

  $ dev/poll/poll -v -s clo -c pol
  #### BEGIN ####
  cmd #1 stp #0: do_con(4): ret=0
  cmd #1 stp #0: do_acc(3): ret=5
  cmd #1 stp #1: do_clo(5): ret=0
  cmd #2 stp #1: do_pol(4): ret=1 ev=0x2005 (IN OUT RDHUP)
  #### END ####

It's interesting to see OUT+HUP since HUP indicates that both directions
were closed, hence nothing may be written now, thus OUT just wants the
write handler to be notified.
diff --git a/dev/poll/poll.c b/dev/poll/poll.c
index 55f922a..91db039 100644
--- a/dev/poll/poll.c
+++ b/dev/poll/poll.c
@@ -32,6 +32,7 @@
 int lfd = -1;
 int cfd = -1;
 int sfd = -1;
+int connected = 0;
 struct sockaddr_in saddr, caddr;
 socklen_t salen, calen;
 
@@ -46,6 +47,7 @@
 	       "    -l <actions>  perform <action> on listening socket\n"
 	       "\n"
 	       "actions for -c/-s/-l (multiple may be delimited by commas) :\n"
+	       "    con           connect to listener, implicit before first -c/-s\n"
 	       "    acc           accept on listener, implicit before first -s\n"
 	       "    snd           send a few bytes of data\n"
 	       "    mor           send a few bytes of data with MSG_MORE\n"
@@ -90,6 +92,16 @@
 		printf("cmd #%d stp #%d: %s(%d): ret=%d%s\n", cmd, cmdstep, __FUNCTION__, fd, ret, get_errno(ret));
 }
 
+void do_con(int fd)
+{
+	int ret;
+
+        ret = connect(cfd, (const struct sockaddr*)&saddr, salen);
+	if (verbose)
+		printf("cmd #%d stp #%d: %s(%d): ret=%d%s\n", cmd, cmdstep, __FUNCTION__, fd, ret, get_errno(ret));
+	connected = 1;
+}
+
 void do_snd(int fd)
 {
 	int ret;
@@ -251,13 +263,6 @@
 	if (cfd < 0)
 		die("socket(c)");
 
-        if (connect(cfd, (const struct sockaddr*)&saddr, salen) == -1)
-		die("connect()");
-
-	/* connection is pending in accept queue, accept() will either be
-	 * explicit with "-l acc" below, or implicit on "-s <cmd>"
-	 */
-
 	arg0 = argv[0];
 	if (argc < 2) {
 		usage(arg0);
@@ -284,10 +289,18 @@
 			break;
 		case 'c' :
 			cmd++; cmdstep = 0;
+			if (!connected) {
+				do_con(cfd);
+				/* connection is pending in accept queue, accept() will either be
+				 * explicit with "-l acc" below, or implicit on "-s <cmd>"
+				 */
+			}
 			fd = cfd;
 			break;
 		case 's' :
 			cmd++; cmdstep = 0;
+			if (!connected)
+				do_con(cfd);
 			if (sfd < 0)
 				do_acc(lfd);
 			if (sfd < 0)
@@ -315,6 +328,9 @@
 				if (strcmp(word, "acc") == 0) {
 					do_acc(fd);
 				}
+				else if (strcmp(word, "con") == 0) {
+					do_con(fd);
+				}
 				else if (strcmp(word, "snd") == 0) {
 					do_snd(fd);
 				}