From 3da1787c062ff366d16267b888bd5a518d788410 Mon Sep 17 00:00:00 2001
From: Ralph Castain <rhc@open-mpi.org>
Date: Wed, 15 Feb 2012 04:16:05 +0000
Subject: [PATCH] Allow there to be no default hostfile without generating an
 error

This commit was SVN r25930.
---
 orte/runtime/orte_globals.c    |  1 +
 orte/runtime/orte_globals.h    |  1 +
 orte/runtime/orte_mca_params.c | 18 +++++++++++++-----
 orte/util/hostfile/hostfile.c  | 21 +++++++++++++++++++--
 4 files changed, 34 insertions(+), 7 deletions(-)

diff --git a/orte/runtime/orte_globals.c b/orte/runtime/orte_globals.c
index fa920f5aca..733f58f93c 100644
--- a/orte/runtime/orte_globals.c
+++ b/orte/runtime/orte_globals.c
@@ -150,6 +150,7 @@ bool orte_report_launch_progress = false;
 
 /* allocation specification */
 char *orte_default_hostfile = NULL;
+bool orte_default_hostfile_given = false;
 char *orte_rankfile = NULL;
 #ifdef __WINDOWS__
 char *orte_ccp_headnode;
diff --git a/orte/runtime/orte_globals.h b/orte/runtime/orte_globals.h
index 93cc06ea38..c2f71ed2f2 100644
--- a/orte/runtime/orte_globals.h
+++ b/orte/runtime/orte_globals.h
@@ -615,6 +615,7 @@ ORTE_DECLSPEC extern bool orte_report_launch_progress;
 
 /* allocation specification */
 ORTE_DECLSPEC extern char *orte_default_hostfile;
+ORTE_DECLSPEC extern bool orte_default_hostfile_given;
 ORTE_DECLSPEC extern char *orte_rankfile;
 #ifdef __WINDOWS__
 ORTE_DECLSPEC extern char *orte_ccp_headnode;
diff --git a/orte/runtime/orte_mca_params.c b/orte/runtime/orte_mca_params.c
index 95af9231e8..a55b594546 100644
--- a/orte/runtime/orte_mca_params.c
+++ b/orte/runtime/orte_mca_params.c
@@ -251,15 +251,23 @@ int orte_register_params(void)
                                 false, false, 1000, &orte_timeout_usec_per_proc);
     
     /* default hostfile */
-    asprintf(&orte_default_hostfile, "%s/etc/openmpi-default-hostfile", opal_install_dirs.prefix);
     mca_base_param_reg_string_name("orte", "default_hostfile",
                                    "Name of the default hostfile (relative or absolute path, \"none\" to ignore environmental or default MCA param setting)",
-                                   false, false, orte_default_hostfile, &orte_default_hostfile);
-    if (0 == strcmp(orte_default_hostfile, "none")) {
-        free(orte_default_hostfile);
+                                   false, false, NULL, &strval);
+    if (NULL == strval) {
+        /* nothing was given, so define the default */
+        asprintf(&orte_default_hostfile, "%s/etc/openmpi-default-hostfile", opal_install_dirs.prefix);
+        /* flag that nothing was given */
+        orte_default_hostfile_given = false;
+    } else if (0 == strcmp(orte_default_hostfile, "none")) {
         orte_default_hostfile = NULL;
+        /* flag that it was given */
+        orte_default_hostfile_given = true;
+    } else {
+        orte_default_hostfile = strval;
+        /* flag that it was given */
+        orte_default_hostfile_given = true;
     }
-
     
 #ifdef __WINDOWS__
     mca_base_param_reg_string_name("orte", "ccp_headnode",
diff --git a/orte/util/hostfile/hostfile.c b/orte/util/hostfile/hostfile.c
index 87eb5413da..aec28395b9 100644
--- a/orte/util/hostfile/hostfile.c
+++ b/orte/util/hostfile/hostfile.c
@@ -419,8 +419,25 @@ static int hostfile_parse(const char *hostfile, opal_list_t* updates, opal_list_
     orte_util_hostfile_done = false;
     orte_util_hostfile_in = fopen(hostfile, "r");
     if (NULL == orte_util_hostfile_in) {
-        orte_show_help("help-hostfile.txt", "no-hostfile", true, hostfile);
-        rc = ORTE_ERR_NOT_FOUND;
+        if (NULL == orte_default_hostfile ||
+            0 != strcmp(orte_default_hostfile, hostfile)) {
+            /* not the default hostfile, so not finding it
+             * is an error
+             */
+            orte_show_help("help-hostfile.txt", "no-hostfile", true, hostfile);
+            rc = ORTE_ERR_SILENT;
+            goto unlock;
+        }
+        /* if this is the default hostfile and it was given,
+         * then it's an error
+         */
+        if (orte_default_hostfile_given) {
+            orte_show_help("help-hostfile.txt", "no-hostfile", true, hostfile);
+            rc = ORTE_ERR_NOT_FOUND;
+            goto unlock;
+        }
+        /* otherwise, not finding it is okay */
+        rc = ORTE_SUCCESS;
         goto unlock;
     }