mgmt/Glusterd: Implementation volume set help/help-xml

Signed-off-by: Kaushik BV <kaushikbv@gluster.com>
Signed-off-by: Anand Avati <avati@gluster.com>

BUG: 2041 (volume set help option)
URL: http://bugs.gluster.com/cgi-bin/bugzilla3/show_bug.cgi?id=2041

2 files changed, 113 insertions, 0 deletions

diff --git a/libglusterfs/src/xlator.c b/libglusterfs/src/xlator.c
index d38754ecdd4..3674bddd97e 100644
--- a/libglusterfs/src/xlator.c
+++ b/libglusterfs/src/xlator.c
@@ -569,6 +569,65 @@ xlator_set_type_virtual (xlator_t *xl, const char *type)
                 return -1;
 }
 
+int32_t
+xlator_volopt_dynload (char *xlator_type, void **dl_handle,
+                    volume_opt_list_t *opt_list)
+{
+        int                     ret = -1;
+        char                    *name = NULL;
+        void                    *handle = NULL;
+        volume_opt_list_t       *vol_opt = NULL;
+
+        GF_VALIDATE_OR_GOTO ("xlator", xlator_type, out);
+
+        GF_ASSERT (dl_handle);
+
+        if (*dl_handle)
+                if (dlclose (*dl_handle))
+                        gf_log ("xlator", GF_LOG_WARNING, "Unable to close "
+                                  "previously opened handle( may be stale)."
+                                  "Ignoring the invalid handle");
+
+        ret = gf_asprintf (&name, "%s/%s.so", XLATORDIR, xlator_type);
+        if (-1 == ret) {
+                gf_log ("xlator", GF_LOG_ERROR, "asprintf failed");
+                goto out;
+        }
+
+        ret = -1;
+
+        gf_log ("xlator", GF_LOG_TRACE, "attempt to load file %s", name);
+
+        handle = dlopen (name, RTLD_NOW|RTLD_GLOBAL);
+        if (!handle) {
+                gf_log ("xlator", GF_LOG_WARNING, "%s", dlerror ());
+                goto out;
+        }
+        *dl_handle = handle;
+
+        INIT_LIST_HEAD (&opt_list->list);
+
+        vol_opt = GF_CALLOC (1, sizeof (volume_opt_list_t),
+                         gf_common_mt_volume_opt_list_t);
+
+        if (!vol_opt) {
+                goto out;
+        }
+
+        if (!(vol_opt->given_opt = dlsym (handle, "options"))) {
+                dlerror ();
+                gf_log ("xlator", GF_LOG_DEBUG,
+                         "Strict option validation not enforced -- neglecting");
+        }
+        list_add_tail (&vol_opt->list, &opt_list->list);
+
+        ret = 0;
+ out:
+        gf_log ("xlator", GF_LOG_DEBUG, "Returning %d", ret);
+        return ret;
+
+}
+
 
 int32_t
 xlator_dynload (xlator_t *xl)
@@ -1226,3 +1285,51 @@ glusterd_check_log_level (const char *value)
 
         return log_level;
 }
+
+int
+xlator_get_volopt_info (struct list_head *opt_list, char *key, char **def_val,
+                         char **descr)
+{
+
+        int                     index = 0;
+        int                     ret = -1;
+        volume_opt_list_t       *vol_list = NULL;
+        volume_option_t         *opt = NULL;
+
+        if (!opt_list || !key || !def_val ) {
+                gf_log ("", GF_LOG_WARNING, " Parameters to the function not "
+                         "valid");
+                ret = -1;
+                goto out;
+        }
+
+        if (list_empty (opt_list)) {
+                gf_log ("xlator", GF_LOG_WARNING, "No elements in Volume option"
+                         " list");
+                ret = -1;
+                goto out;
+        }
+
+
+        vol_list = list_entry (opt_list->next, volume_opt_list_t, list);
+
+        opt = vol_list->given_opt;
+
+        for (index = 0; opt[index].key && opt[index].key[0] ; index++) {
+                if (strncmp (key, opt[index].key[0], strlen (key)))
+                        continue;
+
+                *def_val = opt[index].default_value;
+                if (descr)
+                        *descr = opt[index].description;
+                ret = 0;
+                goto out;
+        }
+
+        ret = -1;
+
+out:
+        gf_log ("", GF_LOG_DEBUG, "Returning %d", ret);
+        return ret;
+
+}
diff --git a/libglusterfs/src/xlator.h b/libglusterfs/src/xlator.h
index 0a2dcbafd76..2af1012ab2d 100644
--- a/libglusterfs/src/xlator.h
+++ b/libglusterfs/src/xlator.h
@@ -787,6 +787,7 @@ typedef struct volume_options {
         char                *value[ZR_OPTION_MAX_ARRAY_SIZE];
                                    /* If specified, will check for one of
 				      the value from this array */
+        char                *default_value;
 	char                *description; /* about the key */
 } volume_option_t;
 
@@ -876,6 +877,11 @@ int is_gf_log_command (xlator_t *trans, const char *name, char *value);
 int xlator_validate_rec (xlator_t *xlator, char **op_errstr);
 int graph_reconf_validateopt (glusterfs_graph_t *graph, char **op_errstr);
 int glusterd_check_log_level (const char *value);
+int32_t xlator_volopt_dynload (char *xlator_type, void **dl_handle,
+                    volume_opt_list_t *vol_opt_handle);
+int xlator_get_volopt_info (struct list_head *opt_list, char *key,
+                            char **def_val, char **descr);
+
 
 #define GF_STAT_PRINT_FMT_STR "%"PRIx64",%"PRIx64",%"PRIx32",%"PRIx32",%"PRIx32",%"PRIx32",%"PRIx64",%"PRIx64",%"PRIx32",%"PRIx64",%"PRIx32",%"PRIx32",%"PRIx32",%"PRIx32",%"PRIx32",%"PRIx32"\n"