Detect/warn of illegal node names

If we detect that someone has given us an incorrect node name, provide a helpful message telling them as it is almost certainly a typo.

Signed-off-by: Ralph Castain <[email protected]>
(cherry picked from commit 3269f2d)

Author: Ralph Castain

orte/util/help-regex.txt

@@ -12,6 +12,7 @@
 #                         All rights reserved.
 # Copyright (c) 2014      Research Organization for Information Science
 #                         and Technology (RIST). All rights reserved.
+# Copyright (c) 2017      Intel, Inc. All rights reserved.
 # $COPYRIGHT$
 #
 # Additional copyrights may follow
@@ -68,3 +69,18 @@ digits in the names:
    regexp: %s
 
 Please contact the Open MPI help list for assistance.
+#
+[regex:invalid-name]
+While trying to create a regular expression of the node names
+used in this application, the regex parser has detected the
+presence of an illegal character in the following node name:
+
+  node:  %s
+
+Node names must be composed of a combination of ascii letters,
+digits, dots, and the hyphen ('-') character. See the following
+for an explanation:
+
+  https://en.wikipedia.org/wiki/Hostname
+
+Please correct the error and try again.

orte/util/nidmap.c

@@ -209,7 +209,7 @@ int orte_util_nidmap_create(opal_pointer_array_t *pool, char **regex)
     char *node;
     char prefix[ORTE_MAX_NODE_PREFIX];
     int i, j, n, len, startnum, nodenum, numdigits;
-    bool found, fullname;
+    bool found;
     char *suffix, *sfx, *nodenames;
     orte_regex_node_t *ndreg;
     orte_regex_range_t *range, *rng;
@@ -271,7 +271,6 @@ int orte_util_nidmap_create(opal_pointer_array_t *pool, char **regex)
         }
         node = nptr->name;
         /* determine this node's prefix by looking for first digit char */
-        fullname = false;
         len = strlen(node);
         startnum = -1;
         memset(prefix, 0, ORTE_MAX_NODE_PREFIX);
@@ -289,18 +288,16 @@ int orte_util_nidmap_create(opal_pointer_array_t *pool, char **regex)
                 }
                 continue;
             }
-            if ('.' == node[i]) {
-                /* just use the entire name */
-                fullname = true;
-                break;
+            /* this must be either an alpha, a '.', or '-' */
+            if (!isalpha(node[i]) && '-' != node[i] && '.' != node[i]) {
+                orte_show_help("help-regex.txt", "regex:invalid-name", true, node);
+                return ORTE_ERR_SILENT;
             }
-            /* this is either an alpha or '-' */
-            assert(isalpha(node[i]) || '-' == node[i]);
             if (startnum < 0) {
                 prefix[j++] = node[i];
             }
         }
-        if (fullname || startnum < 0) {
+        if (startnum < 0) {
             /* can't compress this name - just add it to the list */
             ndreg = OBJ_NEW(orte_regex_node_t);
             ndreg->prefix = strdup(node);