Add a new API to the show_help system that allows external users (e.g., libraries built upon OMPI) to define their own locations for show_help files. This allows such users to exploit the rather nice features of the OPAL show_help system -without- interfering with the ability of the ORTE and OMPI layers to use show_help themselves.

Reviewed by Jeff to protect toes...and to get some good comments :-)

This commit was SVN r22026.

opal/runtime/opal_init.c

@@ -195,6 +195,13 @@ opal_init_util(void)
     /* initialize the output system */
     opal_output_init();
 
+    /* initialize install dirs code */
+    if (OPAL_SUCCESS != (ret = opal_installdirs_base_open())) {
+        fprintf(stderr, "opal_installdirs_base_open() failed -- process will likely abort (%s:%d, returned %d instead of OPAL_INIT)\n",
+                __FILE__, __LINE__, ret);
+        return ret;
+    }
+    
     /* initialize the help system */
     opal_show_help_init();
 
@@ -206,13 +213,6 @@ opal_init_util(void)
         goto return_error;
     }
 
-    /* initialize install dirs code */
-    if (OPAL_SUCCESS != (ret = opal_installdirs_base_open())) {
-        fprintf(stderr, "opal_installdirs_base_open() failed -- process will likely abort (%s:%d, returned %d instead of OPAL_INIT)\n",
-                __FILE__, __LINE__, ret);
-        return ret;
-    }
-
     /* init the trace function */
     opal_trace_init();
 

opal/util/show_help.c

@@ -40,16 +40,18 @@
 static const char *default_filename = "help-messages";
 static const char *dash_line = "--------------------------------------------------------------------------\n";
 static int output_stream = -1;
-
+static char **search_dirs = NULL;
 
 int opal_show_help_init(void)
 {
     opal_output_stream_t lds;
-
+    
     OBJ_CONSTRUCT(&lds, opal_output_stream_t);
     lds.lds_want_stderr = true;
     output_stream = opal_output_open(&lds);
-
+    
+    opal_argv_append_nosize(&search_dirs, opal_install_dirs.pkgdatadir);
+    
     return OPAL_SUCCESS;
 }
 
@@ -57,6 +59,12 @@ int opal_show_help_finalize(void)
 {
     opal_output_close(output_stream);
     output_stream = -1;
+    
+    /* destruct the search list */
+    if (NULL != search_dirs) {
+        opal_argv_free(search_dirs);
+    };
+    
     return OPAL_SUCCESS;
 }
 
@@ -118,32 +126,36 @@ static int open_file(const char *base, const char *topic)
     char *filename;
     char *err_msg = NULL;
     size_t base_len;
-
+    int i;
+    
     /* If no filename was supplied, use the default */
 
     if (NULL == base) {
         base = default_filename;
     }
-
+    
     /* Try to open the file.  If we can't find it, try it with a .txt
-       extension. */
+     * extension.
-
+     */
-    filename = opal_os_path( false, opal_install_dirs.pkgdatadir, base, NULL );
+    for (i=0; NULL != search_dirs[i]; i++) {
-    opal_show_help_yyin = fopen(filename, "r");
+        filename = opal_os_path( false, search_dirs[i], base, NULL );
-    if (NULL == opal_show_help_yyin) {
+        opal_show_help_yyin = fopen(filename, "r");
-        asprintf(&err_msg, "%s: %s", filename, strerror(errno));
+        if (NULL == opal_show_help_yyin) {
-        base_len = strlen(base);
+            asprintf(&err_msg, "%s: %s", filename, strerror(errno));
-        if (4 > base_len || 0 != strcmp(base + base_len - 4, ".txt")) {
+            base_len = strlen(base);
-            free(filename);
+            if (4 > base_len || 0 != strcmp(base + base_len - 4, ".txt")) {
-            asprintf(&filename, "%s%s%s.txt", opal_install_dirs.pkgdatadir,
+                free(filename);
-                     OPAL_PATH_SEP, base);
+                asprintf(&filename, "%s%s%s.txt", search_dirs[i], OPAL_PATH_SEP, base);
-            opal_show_help_yyin = fopen(filename, "r");
+                opal_show_help_yyin = fopen(filename, "r");
+            }
+        }
+        free(filename);
+        if (NULL != opal_show_help_yyin) {
+            break;
         }
     }
-    free(filename);
 
     /* If we still couldn't open it, then something is wrong */
-
     if (NULL == opal_show_help_yyin) {
         opal_output(output_stream, "%sSorry!  You were supposed to get help about:\n    %s\nBut I couldn't open the help file:\n    %s.  Sorry!\n%s", dash_line, topic, err_msg, dash_line);
         free(err_msg);
@@ -330,3 +342,9 @@ int opal_show_help(const char *filename, const char *topic,
 
     return rc;
 }
+
+int opal_show_help_add_dir(const char *directory)
+{
+    opal_argv_append_nosize(&search_dirs, directory);
+    return OPAL_SUCCESS;
+}

opal/util/show_help.h

@@ -154,6 +154,21 @@ OPAL_DECLSPEC char* opal_show_help_vstring(const char *filename,
                                           const char *topic, 
                                           bool want_error_header, va_list ap);
 
+/**
+ * This function adds another search location for the files that
+ * back show_help messages. Locations will be searched starting
+ * with the prefix installation directory, then cycled through
+ * any additional directories in the order they were added
+ *
+ * This interface allows libraries that use OMPI to take advantage
+ * of the show_help functionality. OMPI defines the show_help directory
+ * based on where OMPI was installed. However, if the library wants to
+ * use show_help to provide error output specific to itself, then it
+ * nees to tell show_help how to find its own show_help files - without
+ * interfering with the linked ORTE libs when they need to do show_help.
+ */
+OPAL_DECLSPEC int opal_show_help_add_dir(const char *directory);
+
 /** 
  * \internal
  *