Extend the dstore framework to include a new "update_handle" API so the attributes of an existing handle can be changed. We can't just open a new handle as the upper layers won't know where to find the info. :-(

opal/mca/dstore/base/base.h

@@ -80,6 +80,7 @@ typedef struct {
 OBJ_CLASS_DECLARATION(opal_dstore_proc_data_t);
 
 OPAL_DECLSPEC int opal_dstore_base_open(const char *name, opal_list_t *attrs);
+OPAL_DECLSPEC int opal_dstore_base_update(int dstorehandle, opal_list_t *attrs);
 OPAL_DECLSPEC int opal_dstore_base_close(int dstorehandle);
 OPAL_DECLSPEC int opal_dstore_base_store(int dstorehandle,
                                          const opal_identifier_t *id,

opal/mca/dstore/base/dstore_base_frame.c

@@ -31,6 +31,7 @@
 
 opal_dstore_base_API_t opal_dstore = {
     opal_dstore_base_open,
+    opal_dstore_base_update,
     opal_dstore_base_close,
     opal_dstore_base_store,
     opal_dstore_base_fetch,

opal/mca/dstore/base/dstore_base_stubs.c

@@ -49,6 +49,25 @@ int opal_dstore_base_open(const char *name, opal_list_t *attrs)
     return OPAL_ERROR;
 }
 
+int opal_dstore_base_update(int dstorehandle, opal_list_t *attrs)
+{
+    int rc;
+
+    if (dstorehandle < 0) {
+        return OPAL_ERR_NOT_INITIALIZED;
+    }
+
+    if (NULL == opal_dstore_base.storage_component->update_handle) {
+        return OPAL_SUCCESS;
+    }
+
+    if (OPAL_SUCCESS != (rc = opal_dstore_base.storage_component->update_handle(dstorehandle, attrs))) {
+        OPAL_ERROR_LOG(rc);
+    }
+
+    return rc;
+}
+
 int opal_dstore_base_close(int dstorehandle)
 {
     opal_dstore_handle_t *hdl;

opal/mca/dstore/dstore.h

@@ -66,6 +66,15 @@ OPAL_DECLSPEC extern int opal_dstore_nonpeer;
 typedef int (*opal_dstore_base_API_open_fn_t)(const char *name,
                                               opal_list_t *attributes);
 
+/*
+ * Update an existing handle
+ *
+ * Sometimes an existing handle requires an update to its attributes, so
+ * provide an API for doing so
+ */
+typedef int (*opal_dstore_base_API_update_fn_t)(int dstorehandle,
+                                                opal_list_t *attributes);
+
 /*
  * Close a database handle
  *
@@ -110,6 +119,7 @@ typedef int (*opal_dstore_base_API_remove_fn_t)(int dstorehandle,
  */
 typedef struct {
     opal_dstore_base_API_open_fn_t           open;
+    opal_dstore_base_API_update_fn_t         update;
     opal_dstore_base_API_close_fn_t          close;
     opal_dstore_base_API_store_fn_t          store;
     opal_dstore_base_API_fetch_fn_t          fetch;
@@ -174,6 +184,9 @@ typedef struct {
 /* create and return a datastore module */
 typedef opal_dstore_base_module_t* (*mca_dstore_base_component_create_hdl_fn_t)(opal_list_t *attributes);
 
+/* update an existing handle */
+typedef int (*mca_dstore_base_component_update_hdl_fn_t)(int hdl, opal_list_t *attributes);
+
 /* provide a chance for the component to finalize */
 typedef void (*mca_dstore_base_component_finalize_fn_t)(void);
 
@@ -181,6 +194,7 @@ typedef struct {
     mca_base_component_t                      base_version;
     mca_base_component_data_t                 base_data;
     mca_dstore_base_component_create_hdl_fn_t create_handle;
+    mca_dstore_base_component_update_hdl_fn_t update_handle;
     mca_dstore_base_component_finalize_fn_t   finalize;
 } opal_dstore_base_component_t;
 

opal/mca/dstore/hash/dstore_hash_component.c

@@ -53,6 +53,7 @@ opal_dstore_base_component_t mca_dstore_hash_component = {
         MCA_BASE_METADATA_PARAM_CHECKPOINT
     },
     component_create,
+    NULL,
     NULL
 };