From 03f6a8529c6ac8c9d60eb7e2febe114ba3d22645 Mon Sep 17 00:00:00 2001
From: Brian Barrett <brbarret@open-mpi.org>
Date: Sat, 4 Feb 2006 23:26:58 +0000
Subject: [PATCH] * Fix situation where we were unlocking a mutex we didn't own
 in an error   cleanup code in the signal part of the event library * Only
 attempt to forward standard input if we have a controlling terminal  
 (isatty() returns 1) and we are the foreground process OR we do not have   a
 controlling terminal (isatty() returns 0).  If we have a controlling  
 terminal, check at each SIGCONT if we should change our forwarding,   since
 our foreground / background status may have changed.

  Unfortunately, there isn't a great way in the iof framework to know if
  we are capturing a starter's stdin.  Use the logic that if it's a source
  AND tagged as standard input, it's a starter's stdin.  This seems to
  work for all the common usages.

Both these need to go to the v1.0 branch.

This commit was SVN r8894.
---
 opal/event/signal.c                   |  3 +-
 orte/mca/iof/base/iof_base_endpoint.c | 56 ++++++++++++++++++++++++---
 orte/mca/iof/base/iof_base_endpoint.h |  1 +
 3 files changed, 52 insertions(+), 8 deletions(-)

diff --git a/opal/event/signal.c b/opal/event/signal.c
index 475df73b69..d6796e57fe 100644
--- a/opal/event/signal.c
+++ b/opal/event/signal.c
@@ -127,8 +127,7 @@ opal_evsignal_add(sigset_t *evsigmask, struct opal_event *ev)
            gives a window where a signal handler *should* be installed
            but actually is not. */
         if (opal_evsel->recalc && opal_evsel->recalc(opal_evbase, 0) == -1) {
-            opal_output(0, "opal_event_loop: opal_evsel->recalc() failed.");
-            opal_mutex_unlock(&opal_event_lock);
+            opal_output(0, "opal_evsignal_add: opal_evsel->recalc() failed.");
             return (-1);
         }
 
diff --git a/orte/mca/iof/base/iof_base_endpoint.c b/orte/mca/iof/base/iof_base_endpoint.c
index dc1d33530a..617187da23 100644
--- a/orte/mca/iof/base/iof_base_endpoint.c
+++ b/orte/mca/iof/base/iof_base_endpoint.c
@@ -223,6 +223,31 @@ static void orte_iof_base_endpoint_write_handler(int sd, short flags, void *user
     OPAL_THREAD_UNLOCK(&orte_iof_base.iof_lock);
 }
 
+
+/* return true if we should read stdin from fd, false otherwise */
+static bool orte_iof_base_endpoint_stdin_check(int fd)
+{
+    if (isatty(fd) && (getpgrp() != tcgetpgrp(fd))) {
+        return false;
+    } else {
+        return true;
+    }
+}
+
+
+static void orte_iof_base_endpoint_stdin_cb(int sd, short flags, void *user)
+{
+    orte_iof_base_endpoint_t* endpoint = (orte_iof_base_endpoint_t*)user; 
+    bool should_process = orte_iof_base_endpoint_stdin_check(endpoint->ep_fd);
+
+    if (should_process) {
+        opal_event_add(&endpoint->ep_event, 0);
+    } else {
+        opal_event_del(&endpoint->ep_event);
+    }
+}
+
+
 /*
  * Lookup existing endpoint matching parameters
  * supplied to create.
@@ -289,13 +314,32 @@ int orte_iof_base_endpoint_create(
     /* setup event handler */
     switch(mode) {
         case ORTE_IOF_SOURCE:
+            if (tag == ORTE_IOF_STDIN && isatty(endpoint->ep_fd)) {
+                /* We should avoid trying to read from stdin if we
+                   have a terminal, but are backgrounded.  Catch the
+                   signals that are commonly used when we switch
+                   between being backgrounded and not.  If the
+                   filedescriptor is not a tty, don't worry about it
+                   and always stay connected. */
+                opal_signal_set(&(endpoint->ep_stdin_event),
+                                SIGCONT,
+                                orte_iof_base_endpoint_stdin_cb,
+                                endpoint);
+                opal_signal_add(&(endpoint->ep_stdin_event), NULL);
+            }
+
+            /* always setup the event, but only add it if we should be
+               reading from stdin right now (per rules above) */
             opal_event_set(
-                &endpoint->ep_event,
-                endpoint->ep_fd,
-                OPAL_EV_READ|OPAL_EV_PERSIST,
-                orte_iof_base_endpoint_read_handler,
-                endpoint);
-            opal_event_add(&endpoint->ep_event, 0);
+                           &endpoint->ep_event,
+                           endpoint->ep_fd,
+                           OPAL_EV_READ|OPAL_EV_PERSIST,
+                           orte_iof_base_endpoint_read_handler,
+                           endpoint);
+            if (tag != ORTE_IOF_STDIN || 
+                orte_iof_base_endpoint_stdin_check(endpoint->ep_fd)) {
+                opal_event_add(&endpoint->ep_event, 0);
+            }
             break;
         case ORTE_IOF_SINK:
             opal_event_set(
diff --git a/orte/mca/iof/base/iof_base_endpoint.h b/orte/mca/iof/base/iof_base_endpoint.h
index 16dcffe8dd..8cfbfcdb9e 100644
--- a/orte/mca/iof/base/iof_base_endpoint.h
+++ b/orte/mca/iof/base/iof_base_endpoint.h
@@ -34,6 +34,7 @@ struct orte_iof_base_endpoint_t {
     uint32_t ep_seq;
     uint32_t ep_ack;
     opal_event_t ep_event;
+    opal_event_t ep_stdin_event;
     opal_list_t ep_frags;
     opal_list_t ep_callbacks;
 };