Refactor and standardize group VOL callbacks.

4 files changed, 307 insertions, 115 deletions

diff --git a/src/H5G.c b/src/H5G.c
index 3845c7e..ca89993 100644
--- a/src/H5G.c
+++ b/src/H5G.c
@@ -278,7 +278,7 @@ H5G__close_cb(H5VL_object_t *grp_vol_obj)
     HDassert(grp_vol_obj);
 
     /* Close the group */
-    if(H5VL_group_close(grp_vol_obj->data, grp_vol_obj->plugin->cls, H5P_DATASET_XFER_DEFAULT, H5_REQUEST_NULL) < 0)
+    if(H5VL_group_close(grp_vol_obj, H5P_DATASET_XFER_DEFAULT, H5_REQUEST_NULL) < 0)
         HGOTO_ERROR(H5E_SYM, H5E_CLOSEERROR, FAIL, "unable to close group")
 
     /* Free the VOL object */
@@ -321,7 +321,6 @@ H5Gcreate2(hid_t loc_id, const char *name, hid_t lcpl_id, hid_t gcpl_id,
     H5VL_object_t      *vol_obj = NULL;                     /* object token of loc_id */
     H5VL_loc_params_t   loc_params;
     H5P_genplist_t      *plist;                         /* Property list pointer */
-    hbool_t         vol_wrapper_set = FALSE;            /* Whether the VOL object wrapping context was set up */
     hid_t	            ret_value = H5I_INVALID_HID;    /* Return value */
 
     FUNC_ENTER_API(H5I_INVALID_HID)
@@ -365,14 +364,8 @@ H5Gcreate2(hid_t loc_id, const char *name, hid_t lcpl_id, hid_t gcpl_id,
     loc_params.type         = H5VL_OBJECT_BY_SELF;
     loc_params.obj_type     = H5I_get_type(loc_id);
 
-    /* Set wrapper info in API context */
-    if(H5VL_set_vol_wrapper(vol_obj->data, vol_obj->plugin) < 0)
-        HGOTO_ERROR(H5E_SYM, H5E_CANTSET, H5I_INVALID_HID, "can't set VOL wrapper info")
-    vol_wrapper_set = TRUE;
-
     /* Create the group */
-    if(NULL == (grp = H5VL_group_create(vol_obj->data, loc_params, vol_obj->plugin->cls, name, 
-                                        gcpl_id, gapl_id, H5P_DATASET_XFER_DEFAULT, H5_REQUEST_NULL)))
+    if(NULL == (grp = H5VL_group_create(vol_obj, loc_params, name, gcpl_id, gapl_id, H5P_DATASET_XFER_DEFAULT, H5_REQUEST_NULL)))
         HGOTO_ERROR(H5E_SYM, H5E_CANTINIT, H5I_INVALID_HID, "unable to create group")
 
     /* Get an atom for the group */
@@ -380,12 +373,8 @@ H5Gcreate2(hid_t loc_id, const char *name, hid_t lcpl_id, hid_t gcpl_id,
         HGOTO_ERROR(H5E_SYM, H5E_CANTREGISTER, H5I_INVALID_HID, "unable to atomize group handle")
 
 done:
-    /* Reset object wrapping info in API context */
-    if(vol_wrapper_set && H5VL_reset_vol_wrapper() < 0)
-        HDONE_ERROR(H5E_SYM, H5E_CANTSET, H5I_INVALID_HID, "can't reset VOL wrapper info")
-
     if(H5I_INVALID_HID == ret_value)
-        if(grp && H5VL_group_close(grp, vol_obj->plugin->cls, H5P_DATASET_XFER_DEFAULT, H5_REQUEST_NULL) < 0)
+        if(grp && H5VL_group_close(vol_obj, H5P_DATASET_XFER_DEFAULT, H5_REQUEST_NULL) < 0)
             HDONE_ERROR(H5E_SYM, H5E_CLOSEERROR, H5I_INVALID_HID, "unable to release group")
 
     FUNC_LEAVE_API(ret_value)
@@ -455,8 +444,7 @@ H5Gcreate_anon(hid_t loc_id, hid_t gcpl_id, hid_t gapl_id)
         HGOTO_ERROR(H5E_ARGS, H5E_BADTYPE, H5I_INVALID_HID, "invalid location identifier")
 
     /* Create the group */
-    if(NULL == (grp = H5VL_group_create(vol_obj->data, loc_params, vol_obj->plugin->cls, NULL, 
-                                        gcpl_id, gapl_id, H5P_DATASET_XFER_DEFAULT, H5_REQUEST_NULL)))
+    if(NULL == (grp = H5VL_group_create(vol_obj, loc_params, NULL, gcpl_id, gapl_id, H5P_DATASET_XFER_DEFAULT, H5_REQUEST_NULL)))
         HGOTO_ERROR(H5E_SYM, H5E_CANTINIT, H5I_INVALID_HID, "unable to create group")
 
     /* Get an atom for the group */
@@ -466,7 +454,7 @@ H5Gcreate_anon(hid_t loc_id, hid_t gcpl_id, hid_t gapl_id)
 done:
     /* Cleanup on failure */
     if(H5I_INVALID_HID == ret_value)
-        if(grp && H5VL_group_close(grp, vol_obj->plugin->cls, H5P_DATASET_XFER_DEFAULT, H5_REQUEST_NULL) < 0)
+        if(grp && H5VL_group_close(vol_obj, H5P_DATASET_XFER_DEFAULT, H5_REQUEST_NULL) < 0)
             HDONE_ERROR(H5E_SYM, H5E_CLOSEERROR, H5I_INVALID_HID, "unable to release group")
 
     FUNC_LEAVE_API(ret_value)
@@ -492,10 +480,9 @@ hid_t
 H5Gopen2(hid_t loc_id, const char *name, hid_t gapl_id)
 {
     void               *grp = NULL;                     /* Group opened */
-    H5VL_object_t      *vol_obj = NULL;                     /* object token of loc_id */
+    H5VL_object_t      *vol_obj = NULL;                 /* object token of loc_id */
     H5VL_loc_params_t   loc_params;
-    hbool_t             vol_wrapper_set = FALSE;    /* Whether the VOL object wrapping context was set up */
-    hid_t	            ret_value = H5I_INVALID_HID;    /* Return value */
+    hid_t	        ret_value = H5I_INVALID_HID;    /* Return value */
 
     FUNC_ENTER_API(H5I_INVALID_HID)
     H5TRACE3("i", "i*si", loc_id, name, gapl_id);
@@ -518,13 +505,7 @@ H5Gopen2(hid_t loc_id, const char *name, hid_t gapl_id)
     loc_params.type = H5VL_OBJECT_BY_SELF;
     loc_params.obj_type = H5I_get_type(loc_id);
 
-    /* Set wrapper info in API context */
-    if(H5VL_set_vol_wrapper(vol_obj->data, vol_obj->plugin) < 0)
-        HGOTO_ERROR(H5E_SYM, H5E_CANTSET, H5I_INVALID_HID, "can't set VOL wrapper info")
-    vol_wrapper_set = TRUE;
-
-    if(NULL == (grp = H5VL_group_open(vol_obj->data, loc_params, vol_obj->plugin->cls, 
-                                      name, gapl_id, H5P_DATASET_XFER_DEFAULT, H5_REQUEST_NULL)))
+    if(NULL == (grp = H5VL_group_open(vol_obj, loc_params, name, gapl_id, H5P_DATASET_XFER_DEFAULT, H5_REQUEST_NULL)))
         HGOTO_ERROR(H5E_SYM, H5E_CANTOPENOBJ, H5I_INVALID_HID, "unable to open group")
 
     /* Register an ID for the group */
@@ -532,12 +513,8 @@ H5Gopen2(hid_t loc_id, const char *name, hid_t gapl_id)
         HGOTO_ERROR(H5E_SYM, H5E_CANTREGISTER, H5I_INVALID_HID, "unable to register group")
 
 done:
-    /* Reset object wrapping info in API context */
-    if(vol_wrapper_set && H5VL_reset_vol_wrapper() < 0)
-        HDONE_ERROR(H5E_SYM, H5E_CANTSET, H5I_INVALID_HID, "can't reset VOL wrapper info")
-
     if(H5I_INVALID_HID == ret_value)
-        if(grp && H5VL_group_close(grp, vol_obj->plugin->cls, H5P_DATASET_XFER_DEFAULT, H5_REQUEST_NULL) < 0)
+        if(grp && H5VL_group_close(vol_obj, H5P_DATASET_XFER_DEFAULT, H5_REQUEST_NULL) < 0)
             HDONE_ERROR(H5E_SYM, H5E_CLOSEERROR, H5I_INVALID_HID, "unable to release group")
 
     FUNC_LEAVE_API(ret_value)
@@ -571,8 +548,7 @@ H5Gget_create_plist(hid_t group_id)
         HGOTO_ERROR(H5E_ARGS, H5E_BADTYPE, H5I_INVALID_HID, "not a group ID")
 
     /* Get the group creation property list for the group */
-    if(H5VL_group_get(vol_obj->data, vol_obj->plugin->cls, H5VL_GROUP_GET_GCPL, 
-                      H5P_DATASET_XFER_DEFAULT, H5_REQUEST_NULL, &ret_value) < 0)
+    if(H5VL_group_get(vol_obj, H5VL_GROUP_GET_GCPL, H5P_DATASET_XFER_DEFAULT, H5_REQUEST_NULL, &ret_value) < 0)
         HGOTO_ERROR(H5E_SYM, H5E_CANTGET, H5I_INVALID_HID, "can't get group's creation property list")
 
 done:
@@ -614,8 +590,7 @@ H5Gget_info(hid_t loc_id, H5G_info_t *group_info)
     /* Retrieve the group's information */
     loc_params.type     = H5VL_OBJECT_BY_SELF;
     loc_params.obj_type = id_type;
-    if((ret_value = H5VL_group_get(vol_obj->data, vol_obj->plugin->cls, H5VL_GROUP_GET_INFO, 
-                                   H5P_DATASET_XFER_DEFAULT, H5_REQUEST_NULL, loc_params, group_info)) < 0)
+    if((ret_value = H5VL_group_get(vol_obj, H5VL_GROUP_GET_INFO, H5P_DATASET_XFER_DEFAULT, H5_REQUEST_NULL, loc_params, group_info)) < 0)
         HGOTO_ERROR(H5E_SYM, H5E_CANTGET, FAIL, "unable to get group info")
 
 done:
@@ -667,8 +642,7 @@ H5Gget_info_by_name(hid_t loc_id, const char *name, H5G_info_t *group_info,
     loc_params.obj_type                         = H5I_get_type(loc_id);
 
     /* Retrieve the group's information */
-    if((ret_value = H5VL_group_get(vol_obj->data, vol_obj->plugin->cls, H5VL_GROUP_GET_INFO, 
-                                   H5P_DATASET_XFER_DEFAULT, H5_REQUEST_NULL, loc_params, group_info)) < 0)
+    if((ret_value = H5VL_group_get(vol_obj, H5VL_GROUP_GET_INFO, H5P_DATASET_XFER_DEFAULT, H5_REQUEST_NULL, loc_params, group_info)) < 0)
         HGOTO_ERROR(H5E_SYM, H5E_CANTGET, FAIL, "can't retrieve group info")
 
 done:
@@ -728,8 +702,7 @@ H5Gget_info_by_idx(hid_t loc_id, const char *group_name, H5_index_t idx_type,
     loc_params.obj_type                     = H5I_get_type(loc_id);
 
     /* Retrieve the group's information */
-    if((ret_value = H5VL_group_get(vol_obj->data, vol_obj->plugin->cls, H5VL_GROUP_GET_INFO, 
-                                   H5P_DATASET_XFER_DEFAULT, H5_REQUEST_NULL, loc_params, group_info)) < 0)
+    if((ret_value = H5VL_group_get(vol_obj, H5VL_GROUP_GET_INFO, H5P_DATASET_XFER_DEFAULT, H5_REQUEST_NULL, loc_params, group_info)) < 0)
         HGOTO_ERROR(H5E_SYM, H5E_CANTGET, FAIL, "can't retrieve group info")
 
 done:
@@ -800,8 +773,7 @@ H5Gflush(hid_t group_id)
         HGOTO_ERROR(H5E_SYM, H5E_CANTSET, FAIL, "can't set collective metadata read info")
 
     /* Flush group's metadata to file */
-    if((ret_value = H5VL_group_specific(vol_obj->data, vol_obj->plugin->cls, H5VL_GROUP_FLUSH, 
-                                          H5P_DATASET_XFER_DEFAULT, H5_REQUEST_NULL, group_id)) < 0)
+    if(H5VL_group_specific(vol_obj, H5VL_GROUP_FLUSH, H5P_DATASET_XFER_DEFAULT, H5_REQUEST_NULL, group_id) < 0)
         HGOTO_ERROR(H5E_SYM, H5E_CANTFLUSH, FAIL, "unable to flush group")
 
 done:
@@ -845,8 +817,7 @@ H5Grefresh(hid_t group_id)
     vol_wrapper_set = TRUE;
 
     /* Refresh group's metadata */
-    if((ret_value = H5VL_group_specific(vol_obj->data, vol_obj->plugin->cls, H5VL_GROUP_REFRESH, 
-                                          H5P_DATASET_XFER_DEFAULT, H5_REQUEST_NULL, group_id)) < 0)
+    if(H5VL_group_specific(vol_obj, H5VL_GROUP_REFRESH, H5P_DATASET_XFER_DEFAULT, H5_REQUEST_NULL, group_id) < 0)
         HGOTO_ERROR(H5E_SYM, H5E_CANTLOAD, FAIL, "unable to refresh group")
 
 done:
diff --git a/src/H5Gdeprec.c b/src/H5Gdeprec.c
index d207bc1..df5a1d8 100644
--- a/src/H5Gdeprec.c
+++ b/src/H5Gdeprec.c
@@ -235,8 +235,7 @@ H5Gcreate1(hid_t loc_id, const char *name, size_t size_hint)
         HGOTO_ERROR(H5E_ARGS, H5E_BADTYPE, H5I_INVALID_HID, "invalid location identifier")
 
     /* Create the group */
-    if(NULL == (grp = H5VL_group_create(vol_obj->data, loc_params, vol_obj->plugin->cls, name, tmp_gcpl, 
-                                        H5P_GROUP_ACCESS_DEFAULT, H5P_DATASET_XFER_DEFAULT, H5_REQUEST_NULL)))
+    if(NULL == (grp = H5VL_group_create(vol_obj, loc_params, name, tmp_gcpl, H5P_GROUP_ACCESS_DEFAULT, H5P_DATASET_XFER_DEFAULT, H5_REQUEST_NULL)))
         HGOTO_ERROR(H5E_SYM, H5E_CANTINIT, H5I_INVALID_HID, "unable to create group")
 
     /* Get an atom for the group */
@@ -249,7 +248,7 @@ done:
             HDONE_ERROR(H5E_SYM, H5E_CLOSEERROR, H5I_INVALID_HID, "unable to release property list")
 
     if(H5I_INVALID_HID == ret_value)
-        if(grp && H5VL_group_close(grp, vol_obj->plugin->cls, H5P_DATASET_XFER_DEFAULT, H5_REQUEST_NULL) < 0)
+        if(grp && H5VL_group_close(vol_obj, H5P_DATASET_XFER_DEFAULT, H5_REQUEST_NULL) < 0)
             HDONE_ERROR(H5E_SYM, H5E_CLOSEERROR, H5I_INVALID_HID, "unable to release group")
 
     FUNC_LEAVE_API(ret_value)
@@ -297,8 +296,7 @@ H5Gopen1(hid_t loc_id, const char *name)
         HGOTO_ERROR(H5E_ARGS, H5E_BADTYPE, H5I_INVALID_HID, "invalid location identifier")
 
     /* Open the group */
-    if(NULL == (grp = H5VL_group_open(vol_obj->data, loc_params, vol_obj->plugin->cls, name, H5P_DEFAULT, 
-                                      H5P_DATASET_XFER_DEFAULT, H5_REQUEST_NULL)))
+    if(NULL == (grp = H5VL_group_open(vol_obj, loc_params, name, H5P_DEFAULT, H5P_DATASET_XFER_DEFAULT, H5_REQUEST_NULL)))
         HGOTO_ERROR(H5E_SYM, H5E_CANTOPENOBJ, H5I_INVALID_HID, "unable to open group")
 
     /* Get an atom for the group */
@@ -307,7 +305,7 @@ H5Gopen1(hid_t loc_id, const char *name)
 
 done:
     if(H5I_INVALID_HID == ret_value)
-        if(grp && H5VL_group_close(grp, vol_obj->plugin->cls, H5P_DATASET_XFER_DEFAULT, H5_REQUEST_NULL) < 0)
+        if(grp && H5VL_group_close(vol_obj, H5P_DATASET_XFER_DEFAULT, H5_REQUEST_NULL) < 0)
             HDONE_ERROR(H5E_SYM, H5E_CLOSEERROR, H5I_INVALID_HID, "unable to release group")
 
     FUNC_LEAVE_API(ret_value)
diff --git a/src/H5VLcallback.c b/src/H5VLcallback.c
index 6d28f83..24d9c5c 100644
--- a/src/H5VLcallback.c
+++ b/src/H5VLcallback.c
@@ -103,6 +103,20 @@ static herr_t H5VL__file_optional(void *obj, const H5VL_class_t *cls, hid_t dxpl
     void **req, va_list arguments);
 static herr_t H5VL__file_close(void *obj, const H5VL_class_t *cls, hid_t dxpl_id,
     void **req);
+static void *H5VL__group_create(void *obj, H5VL_loc_params_t loc_params,
+    const H5VL_class_t *cls, const char *name, hid_t gcpl_id, hid_t gapl_id,
+    hid_t dxpl_id, void **req);
+static void *H5VL__group_open(void *obj, H5VL_loc_params_t loc_params,
+    const H5VL_class_t *cls, const char *name, hid_t gapl_id, hid_t dxpl_id,
+    void **req);
+static herr_t H5VL__group_get(void *obj, const H5VL_class_t *cls, H5VL_group_get_t get_type, 
+    hid_t dxpl_id, void **req, va_list arguments);
+static herr_t H5VL__group_specific(void *obj, const H5VL_class_t *cls, H5VL_group_specific_t specific_type, 
+    hid_t dxpl_id, void **req, va_list arguments);
+static herr_t H5VL__group_optional(void *obj, const H5VL_class_t *cls, hid_t dxpl_id,
+    void **req, va_list arguments);
+static herr_t H5VL__group_close(void *obj, const H5VL_class_t *cls,
+    hid_t dxpl_id, void **req);
 
 
 /*********************/
@@ -3012,7 +3026,7 @@ done:
 
 
 /*-------------------------------------------------------------------------
- * Function:	H5VL_group_create
+ * Function:	H5VL__group_create
  *
  * Purpose:	Creates a group through the VOL
  *
@@ -3021,13 +3035,13 @@ done:
  *
  *-------------------------------------------------------------------------
  */
-void *
-H5VL_group_create(void *obj, H5VL_loc_params_t loc_params, const H5VL_class_t *cls,
+static void *
+H5VL__group_create(void *obj, H5VL_loc_params_t loc_params, const H5VL_class_t *cls,
     const char *name, hid_t gcpl_id, hid_t gapl_id, hid_t dxpl_id, void **req)
 {
     void *ret_value = NULL;     /* Return value */
 
-    FUNC_ENTER_NOAPI(NULL)
+    FUNC_ENTER_STATIC
 
     /* Check if the corresponding VOL callback exists */
     if(NULL == cls->group_cls.create)
@@ -3039,6 +3053,43 @@ H5VL_group_create(void *obj, H5VL_loc_params_t loc_params, const H5VL_class_t *c
 
 done:
     FUNC_LEAVE_NOAPI(ret_value)
+} /* end H5VL__group_create() */
+
+
+/*-------------------------------------------------------------------------
+ * Function:	H5VL_group_create
+ *
+ * Purpose:	Creates a group through the VOL
+ *
+ * Return:      Success: Pointer to new group
+ *		Failure: NULL
+ *
+ *-------------------------------------------------------------------------
+ */
+void *
+H5VL_group_create(const H5VL_object_t *vol_obj, H5VL_loc_params_t loc_params,
+    const char *name, hid_t gcpl_id, hid_t gapl_id, hid_t dxpl_id, void **req)
+{
+    hbool_t vol_wrapper_set = FALSE;    /* Whether the VOL object wrapping context was set up */
+    void *ret_value = NULL;     /* Return value */
+
+    FUNC_ENTER_NOAPI(NULL)
+
+    /* Set wrapper info in API context */
+    if(H5VL_set_vol_wrapper(vol_obj->data, vol_obj->plugin) < 0)
+        HGOTO_ERROR(H5E_VOL, H5E_CANTSET, NULL, "can't set VOL wrapper info")
+    vol_wrapper_set = TRUE;
+
+    /* Call the corresponding internal VOL routine */
+    if(NULL == (ret_value = H5VL__group_create(vol_obj->data, loc_params, vol_obj->plugin->cls, name, gcpl_id, gapl_id, dxpl_id, req)))
+        HGOTO_ERROR(H5E_VOL, H5E_CANTCREATE, NULL, "group create failed")
+
+done:
+    /* Reset object wrapping info in API context */
+    if(vol_wrapper_set && H5VL_reset_vol_wrapper() < 0)
+        HDONE_ERROR(H5E_VOL, H5E_CANTRESET, NULL, "can't reset VOL wrapper info")
+
+    FUNC_LEAVE_NOAPI(ret_value)
 } /* end H5VL_group_create() */
 
 
@@ -3070,7 +3121,7 @@ H5VLgroup_create(void *obj, H5VL_loc_params_t loc_params, hid_t plugin_id, const
         HGOTO_ERROR(H5E_ARGS, H5E_BADTYPE, NULL, "not a VOL plugin ID")
 
     /* Call the corresponding internal VOL routine */
-    if(NULL == (ret_value = H5VL_group_create(obj, loc_params, cls, name, gcpl_id, gapl_id, dxpl_id, req)))
+    if(NULL == (ret_value = H5VL__group_create(obj, loc_params, cls, name, gcpl_id, gapl_id, dxpl_id, req)))
         HGOTO_ERROR(H5E_VOL, H5E_CANTCREATE, NULL, "unable to create group")
 
 done:
@@ -3079,7 +3130,7 @@ done:
 
 
 /*-------------------------------------------------------------------------
- * Function:	H5VL_group_open
+ * Function:	H5VL__group_open
  *
  * Purpose:	Opens a group through the VOL
  *
@@ -3088,13 +3139,13 @@ done:
  *
  *-------------------------------------------------------------------------
  */
-void *
-H5VL_group_open(void *obj, H5VL_loc_params_t loc_params, const H5VL_class_t *cls,
+static void *
+H5VL__group_open(void *obj, H5VL_loc_params_t loc_params, const H5VL_class_t *cls,
     const char *name, hid_t gapl_id, hid_t dxpl_id, void **req)
 {
-    void *ret_value = NULL;     /* Return value */
+    void *ret_value = NULL;             /* Return value */
 
-    FUNC_ENTER_NOAPI(NULL)
+    FUNC_ENTER_STATIC
 
     /* Check if the corresponding VOL callback exists */
     if(NULL == cls->group_cls.open)
@@ -3106,6 +3157,43 @@ H5VL_group_open(void *obj, H5VL_loc_params_t loc_params, const H5VL_class_t *cls
 
 done:
     FUNC_LEAVE_NOAPI(ret_value)
+} /* end H5VL__group_open() */
+
+
+/*-------------------------------------------------------------------------
+ * Function:	H5VL_group_open
+ *
+ * Purpose:	Opens a group through the VOL
+ *
+ * Return:      Success: Pointer to group
+ *		Failure: NULL
+ *
+ *-------------------------------------------------------------------------
+ */
+void *
+H5VL_group_open(const H5VL_object_t *vol_obj, H5VL_loc_params_t loc_params,
+    const char *name, hid_t gapl_id, hid_t dxpl_id, void **req)
+{
+    hbool_t vol_wrapper_set = FALSE;    /* Whether the VOL object wrapping context was set up */
+    void *ret_value = NULL;             /* Return value */
+
+    FUNC_ENTER_NOAPI(NULL)
+
+    /* Set wrapper info in API context */
+    if(H5VL_set_vol_wrapper(vol_obj->data, vol_obj->plugin) < 0)
+        HGOTO_ERROR(H5E_VOL, H5E_CANTSET, NULL, "can't set VOL wrapper info")
+    vol_wrapper_set = TRUE;
+
+    /* Call the corresponding internal VOL routine */
+    if(NULL == (ret_value = H5VL__group_open(vol_obj->data, loc_params, vol_obj->plugin->cls, name, gapl_id, dxpl_id, req)))
+        HGOTO_ERROR(H5E_VOL, H5E_CANTOPENOBJ, NULL, "group open failed")
+
+done:
+    /* Reset object wrapping info in API context */
+    if(vol_wrapper_set && H5VL_reset_vol_wrapper() < 0)
+        HDONE_ERROR(H5E_VOL, H5E_CANTRESET, NULL, "can't reset VOL wrapper info")
+
+    FUNC_LEAVE_NOAPI(ret_value)
 } /* end H5VL_group_open() */
 
 
@@ -3137,7 +3225,7 @@ H5VLgroup_open(void *obj, H5VL_loc_params_t loc_params, hid_t plugin_id, const c
         HGOTO_ERROR(H5E_ARGS, H5E_BADTYPE, NULL, "not a VOL plugin ID")
 
     /* Call the corresponding internal VOL routine */
-    if(NULL == (ret_value = H5VL_group_open(obj, loc_params, cls, name, gapl_id, dxpl_id, req)))
+    if(NULL == (ret_value = H5VL__group_open(obj, loc_params, cls, name, gapl_id, dxpl_id, req)))
         HGOTO_ERROR(H5E_VOL, H5E_CANTINIT, NULL, "unable to open group")
 
 done:
@@ -3146,6 +3234,37 @@ done:
 
 
 /*-------------------------------------------------------------------------
+ * Function:	H5VL__group_get
+ *
+ * Purpose:	Get specific information about the group through the VOL
+ *
+ * Return:      Success:    Non-negative
+ *              Failure:    Negative
+ *
+ *-------------------------------------------------------------------------
+ */
+static herr_t
+H5VL__group_get(void *obj, const H5VL_class_t *cls, H5VL_group_get_t get_type, 
+    hid_t dxpl_id, void **req, va_list arguments)
+{
+    herr_t ret_value = SUCCEED;         /* Return value */
+
+    FUNC_ENTER_STATIC
+
+    /* Check if the corresponding VOL callback exists */
+    if(NULL == cls->group_cls.get)
+        HGOTO_ERROR(H5E_VOL, H5E_UNSUPPORTED, FAIL, "VOL plugin has no 'group get' method")
+
+    /* Call the corresponding VOL callback */
+    if((cls->group_cls.get)(obj, get_type, dxpl_id, req, arguments) < 0)
+        HGOTO_ERROR(H5E_VOL, H5E_CANTGET, FAIL, "group get failed")
+
+done:
+    FUNC_LEAVE_NOAPI(ret_value)
+} /* end H5VL__group_get() */
+
+
+/*-------------------------------------------------------------------------
  * Function:	H5VL_group_get
  *
  * Purpose:	Get specific information about the group through the VOL
@@ -3156,23 +3275,25 @@ done:
  *-------------------------------------------------------------------------
  */
 herr_t
-H5VL_group_get(void *obj, const H5VL_class_t *cls, H5VL_group_get_t get_type, 
+H5VL_group_get(const H5VL_object_t *vol_obj, H5VL_group_get_t get_type, 
     hid_t dxpl_id, void **req, ...)
 {
     va_list arguments;                  /* Argument list passed from the API call */
     hbool_t arg_started = FALSE;        /* Whether the va_list has been started */
+    hbool_t vol_wrapper_set = FALSE;    /* Whether the VOL object wrapping context was set up */
     herr_t ret_value = SUCCEED;         /* Return value */
 
     FUNC_ENTER_NOAPI(FAIL)
 
-    /* Check if the corresponding VOL callback exists */
-    if(NULL == cls->group_cls.get)
-        HGOTO_ERROR(H5E_VOL, H5E_UNSUPPORTED, FAIL, "VOL plugin has no 'group get' method")
+    /* Set wrapper info in API context */
+    if(H5VL_set_vol_wrapper(vol_obj->data, vol_obj->plugin) < 0)
+        HGOTO_ERROR(H5E_VOL, H5E_CANTSET, FAIL, "can't set VOL wrapper info")
+    vol_wrapper_set = TRUE;
 
-    /* Call the corresponding VOL callback */
+    /* Call the corresponding internal VOL routine */
     va_start(arguments, req);
     arg_started = TRUE;
-    if((cls->group_cls.get)(obj, get_type, dxpl_id, req, arguments) < 0)
+    if(H5VL__group_get(vol_obj->data, vol_obj->plugin->cls, get_type, dxpl_id, req, arguments) < 0)
         HGOTO_ERROR(H5E_VOL, H5E_CANTGET, FAIL, "group get failed")
 
 done:
@@ -3180,6 +3301,10 @@ done:
     if(arg_started)
         va_end(arguments);
 
+    /* Reset object wrapping info in API context */
+    if(vol_wrapper_set && H5VL_reset_vol_wrapper() < 0)
+        HDONE_ERROR(H5E_VOL, H5E_CANTRESET, FAIL, "can't reset VOL wrapper info")
+
     FUNC_LEAVE_NOAPI(ret_value)
 } /* end H5VL_group_get() */
 
@@ -3210,12 +3335,8 @@ H5VLgroup_get(void *obj, hid_t plugin_id, H5VL_group_get_t get_type,
     if(NULL == (cls = (H5VL_class_t *)H5I_object_verify(plugin_id, H5I_VOL)))
         HGOTO_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "not a VOL plugin ID")
 
-    /* Check if the corresponding VOL callback exists */
-    if(NULL == cls->group_cls.get)
-        HGOTO_ERROR(H5E_VOL, H5E_UNSUPPORTED, FAIL, "VOL plugin has no `group get' method")
-
-    /* Bypass the H5VLint layer, calling the VOL callback directly */
-    if((cls->group_cls.get)(obj, get_type, dxpl_id, req, arguments) < 0)
+    /* Call the corresponding internal VOL routine */
+    if(H5VL__group_get(obj, cls, get_type, dxpl_id, req, arguments) < 0)
         HGOTO_ERROR(H5E_VOL, H5E_CANTGET, FAIL, "unable to execute group get callback")
 
 done:
@@ -3224,6 +3345,37 @@ done:
 
 
 /*-------------------------------------------------------------------------
+ * Function:	H5VL__group_specific
+ *
+ * Purpose:	Specific operation on groups through the VOL
+ *
+ * Return:      Success:    Non-negative
+ *              Failure:    Negative
+ *
+ *-------------------------------------------------------------------------
+ */
+static herr_t
+H5VL__group_specific(void *obj, const H5VL_class_t *cls, H5VL_group_specific_t specific_type, 
+    hid_t dxpl_id, void **req, va_list arguments)
+{
+    herr_t ret_value = SUCCEED;         /* Return value */
+
+    FUNC_ENTER_STATIC
+
+    /* Check if the corresponding VOL callback exists */
+    if(NULL == cls->group_cls.specific)
+        HGOTO_ERROR(H5E_VOL, H5E_UNSUPPORTED, FAIL, "VOL plugin has no 'group specific' method")
+
+    /* Call the corresponding VOL callback */
+    if((cls->group_cls.specific)(obj, specific_type, dxpl_id, req, arguments) < 0)
+        HGOTO_ERROR(H5E_VOL, H5E_CANTOPERATE, FAIL, "unable to execute group specific callback")
+
+done:
+    FUNC_LEAVE_NOAPI(ret_value)
+} /* end H5VL__group_specific() */
+
+
+/*-------------------------------------------------------------------------
  * Function:	H5VL_group_specific
  *
  * Purpose:	Specific operation on groups through the VOL
@@ -3234,23 +3386,25 @@ done:
  *-------------------------------------------------------------------------
  */
 herr_t
-H5VL_group_specific(void *obj, const H5VL_class_t *cls, H5VL_group_specific_t specific_type, 
+H5VL_group_specific(const H5VL_object_t *vol_obj, H5VL_group_specific_t specific_type, 
     hid_t dxpl_id, void **req, ...)
 {
     va_list arguments;                  /* Argument list passed from the API call */
     hbool_t arg_started = FALSE;        /* Whether the va_list has been started */
+    hbool_t vol_wrapper_set = FALSE;    /* Whether the VOL object wrapping context was set up */
     herr_t ret_value = SUCCEED;         /* Return value */
 
     FUNC_ENTER_NOAPI(FAIL)
 
-    /* Check if the corresponding VOL callback exists */
-    if(NULL == cls->group_cls.specific)
-        HGOTO_ERROR(H5E_VOL, H5E_UNSUPPORTED, FAIL, "VOL plugin has no 'group specific' method")
+    /* Set wrapper info in API context */
+    if(H5VL_set_vol_wrapper(vol_obj->data, vol_obj->plugin) < 0)
+        HGOTO_ERROR(H5E_VOL, H5E_CANTSET, FAIL, "can't set VOL wrapper info")
+    vol_wrapper_set = TRUE;
 
-    /* Call the corresponding VOL callback */
+    /* Call the corresponding internal VOL routine */
     va_start(arguments, req);
     arg_started = TRUE;
-    if((cls->group_cls.specific)(obj, specific_type, dxpl_id, req, arguments) < 0)
+    if(H5VL__group_specific(vol_obj->data, vol_obj->plugin->cls, specific_type, dxpl_id, req, arguments) < 0)
         HGOTO_ERROR(H5E_VOL, H5E_CANTOPERATE, FAIL, "unable to execute group specific callback")
 
 done:
@@ -3258,6 +3412,10 @@ done:
     if(arg_started)
         va_end(arguments);
 
+    /* Reset object wrapping info in API context */
+    if(vol_wrapper_set && H5VL_reset_vol_wrapper() < 0)
+        HDONE_ERROR(H5E_VOL, H5E_CANTRESET, FAIL, "can't reset VOL wrapper info")
+
     FUNC_LEAVE_NOAPI(ret_value)
 } /* end H5VL_group_specific() */
 
@@ -3289,12 +3447,8 @@ H5VLgroup_specific(void *obj, hid_t plugin_id, H5VL_group_specific_t specific_ty
     if(NULL == (cls = (H5VL_class_t *)H5I_object_verify(plugin_id, H5I_VOL)))
         HGOTO_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "not a VOL plugin ID")
 
-    /* Check if the corresponding VOL callback exists */
-    if(NULL == cls->group_cls.specific)
-        HGOTO_ERROR(H5E_VOL, H5E_UNSUPPORTED, FAIL, "VOL plugin has no `group specific' method")
-
-    /* Bypass the H5VLint layer, calling the VOL callback directly */
-    if((cls->group_cls.specific)(obj, specific_type, dxpl_id, req, arguments) < 0)
+    /* Call the corresponding internal VOL routine */
+    if(H5VL__group_specific(obj, cls, specific_type, dxpl_id, req, arguments) < 0)
         HGOTO_ERROR(H5E_VOL, H5E_CANTOPERATE, FAIL, "unable to execute group specific callback")
 
 done:
@@ -3303,6 +3457,37 @@ done:
 
 
 /*-------------------------------------------------------------------------
+ * Function:	H5VL__group_optional
+ *
+ * Purpose:	Optional operation specific to plugins.
+ *
+ * Return:      Success:    Non-negative
+ *              Failure:    Negative
+ *
+ *-------------------------------------------------------------------------
+ */
+static herr_t
+H5VL__group_optional(void *obj, const H5VL_class_t *cls, hid_t dxpl_id,
+    void **req, va_list arguments)
+{
+    herr_t ret_value = SUCCEED;         /* Return value */
+
+    FUNC_ENTER_STATIC
+
+    /* Check if the corresponding VOL callback exists */
+    if(NULL == cls->group_cls.optional)
+        HGOTO_ERROR(H5E_VOL, H5E_UNSUPPORTED, FAIL, "VOL plugin has no 'group optional' method")
+
+    /* Call the corresponding VOL callback */
+    if((cls->group_cls.optional)(obj, dxpl_id, req, arguments) < 0)
+        HGOTO_ERROR(H5E_VOL, H5E_CANTOPERATE, FAIL, "unable to execute group optional callback")
+
+done:
+    FUNC_LEAVE_NOAPI(ret_value)
+} /* end H5VL__group_optional() */
+
+
+/*-------------------------------------------------------------------------
  * Function:	H5VL_group_optional
  *
  * Purpose:	Optional operation specific to plugins.
@@ -3313,23 +3498,24 @@ done:
  *-------------------------------------------------------------------------
  */
 herr_t
-H5VL_group_optional(void *obj, const H5VL_class_t *cls, hid_t dxpl_id,
-    void **req, ...)
+H5VL_group_optional(const H5VL_object_t *vol_obj, hid_t dxpl_id, void **req, ...)
 {
     va_list arguments;                  /* Argument list passed from the API call */
     hbool_t arg_started = FALSE;        /* Whether the va_list has been started */
+    hbool_t vol_wrapper_set = FALSE;    /* Whether the VOL object wrapping context was set up */
     herr_t ret_value = SUCCEED;         /* Return value */
 
     FUNC_ENTER_NOAPI(FAIL)
 
-    /* Check if the corresponding VOL callback exists */
-    if(NULL == cls->group_cls.optional)
-        HGOTO_ERROR(H5E_VOL, H5E_UNSUPPORTED, FAIL, "VOL plugin has no 'group optional' method")
+    /* Set wrapper info in API context */
+    if(H5VL_set_vol_wrapper(vol_obj->data, vol_obj->plugin) < 0)
+        HGOTO_ERROR(H5E_VOL, H5E_CANTSET, FAIL, "can't set VOL wrapper info")
+    vol_wrapper_set = TRUE;
 
-    /* Call the corresponding VOL callback */
+    /* Call the corresponding internal VOL routine */
     va_start(arguments, req);
     arg_started = TRUE;
-    if((cls->group_cls.optional)(obj, dxpl_id, req, arguments) < 0)
+    if(H5VL__group_optional(vol_obj->data, vol_obj->plugin->cls, dxpl_id, req, arguments) < 0)
         HGOTO_ERROR(H5E_VOL, H5E_CANTOPERATE, FAIL, "unable to execute group optional callback")
 
 done:
@@ -3337,6 +3523,10 @@ done:
     if(arg_started)
         va_end(arguments);
 
+    /* Reset object wrapping info in API context */
+    if(vol_wrapper_set && H5VL_reset_vol_wrapper() < 0)
+        HDONE_ERROR(H5E_VOL, H5E_CANTRESET, FAIL, "can't reset VOL wrapper info")
+
     FUNC_LEAVE_NOAPI(ret_value)
 } /* end H5VL_group_optional() */
 
@@ -3352,7 +3542,8 @@ done:
  *-------------------------------------------------------------------------
  */
 herr_t
-H5VLgroup_optional(void *obj, hid_t plugin_id, hid_t dxpl_id, void **req, va_list arguments)
+H5VLgroup_optional(void *obj, hid_t plugin_id, hid_t dxpl_id, void **req,
+    va_list arguments)
 {
     H5VL_class_t *cls;                  /* VOL plugin's class struct */
     herr_t ret_value = SUCCEED;         /* Return value */
@@ -3366,12 +3557,8 @@ H5VLgroup_optional(void *obj, hid_t plugin_id, hid_t dxpl_id, void **req, va_lis
     if(NULL == (cls = (H5VL_class_t *)H5I_object_verify(plugin_id, H5I_VOL)))
         HGOTO_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "not a VOL plugin ID")
 
-    /* Check if the corresponding VOL callback exists */
-    if(NULL == cls->group_cls.optional)
-        HGOTO_ERROR(H5E_VOL, H5E_UNSUPPORTED, FAIL, "VOL plugin has no `group optional' method")
-
-    /* Bypass the H5VLint layer, calling the VOL callback directly */
-    if((cls->group_cls.optional)(obj, dxpl_id, req, arguments) < 0)
+    /* Call the corresponding internal VOL routine */
+    if(H5VL__group_optional(obj, cls, dxpl_id, req, arguments) < 0)
         HGOTO_ERROR(H5E_VOL, H5E_CANTOPERATE, FAIL, "unable to execute group optional callback")
 
 done:
@@ -3380,7 +3567,7 @@ done:
 
 
 /*-------------------------------------------------------------------------
- * Function:    H5VL_group_close
+ * Function:    H5VL__group_close
  *
  * Purpose:     Closes a group through the VOL
  *
@@ -3389,27 +3576,63 @@ done:
  *
  *-------------------------------------------------------------------------
  */
-herr_t
-H5VL_group_close(void *grp, const H5VL_class_t *cls, hid_t dxpl_id, void **req)
+static herr_t
+H5VL__group_close(void *obj, const H5VL_class_t *cls, hid_t dxpl_id, void **req)
 {
     herr_t ret_value = SUCCEED;         /* Return value */
 
     /* Sanity check */
-    HDassert(grp);
+    HDassert(obj);
     HDassert(cls);
 
-    FUNC_ENTER_NOAPI(FAIL)
+    FUNC_ENTER_STATIC
 
     /* Check if the corresponding VOL callback exists */
     if(NULL == cls->group_cls.close)
         HGOTO_ERROR(H5E_VOL, H5E_UNSUPPORTED, FAIL, "VOL plugin has no 'group close' method")
 
     /* Call the corresponding VOL callback */
-    if((cls->group_cls.close)(grp, dxpl_id, req) < 0)
+    if((cls->group_cls.close)(obj, dxpl_id, req) < 0)
         HGOTO_ERROR(H5E_VOL, H5E_CANTCLOSEOBJ, FAIL, "group close failed")
 
 done:
     FUNC_LEAVE_NOAPI(ret_value)
+} /* end H5VL__group_close() */
+
+
+/*-------------------------------------------------------------------------
+ * Function:    H5VL_group_close
+ *
+ * Purpose:     Closes a group through the VOL
+ *
+ * Return:      Success:    Non-negative
+ *              Failure:    Negative
+ *
+ *-------------------------------------------------------------------------
+ */
+herr_t
+H5VL_group_close(const H5VL_object_t *vol_obj, hid_t dxpl_id, void **req)
+{
+    hbool_t vol_wrapper_set = FALSE;    /* Whether the VOL object wrapping context was set up */
+    herr_t ret_value = SUCCEED;         /* Return value */
+
+    FUNC_ENTER_NOAPI(FAIL)
+
+    /* Set wrapper info in API context */
+    if(H5VL_set_vol_wrapper(vol_obj->data, vol_obj->plugin) < 0)
+        HGOTO_ERROR(H5E_VOL, H5E_CANTSET, FAIL, "can't set VOL wrapper info")
+    vol_wrapper_set = TRUE;
+
+    /* Call the corresponding internal VOL routine */
+    if(H5VL__group_close(vol_obj->data, vol_obj->plugin->cls, dxpl_id, req) < 0)
+        HGOTO_ERROR(H5E_VOL, H5E_CANTCLOSEOBJ, FAIL, "group close failed")
+
+done:
+    /* Reset object wrapping info in API context */
+    if(vol_wrapper_set && H5VL_reset_vol_wrapper() < 0)
+        HDONE_ERROR(H5E_VOL, H5E_CANTRESET, FAIL, "can't reset VOL wrapper info")
+
+    FUNC_LEAVE_NOAPI(ret_value)
 } /* end H5VL_group_close() */
 
 
@@ -3424,22 +3647,22 @@ done:
  *-------------------------------------------------------------------------
  */
 herr_t
-H5VLgroup_close(void *grp, hid_t plugin_id, hid_t dxpl_id, void **req)
+H5VLgroup_close(void *obj, hid_t plugin_id, hid_t dxpl_id, void **req)
 {
     H5VL_class_t *cls;                  /* VOL plugin's class struct */
     herr_t ret_value = SUCCEED;         /* Return value */
 
     FUNC_ENTER_API_NOINIT
-    H5TRACE4("e", "*xii**x", grp, plugin_id, dxpl_id, req);
+    H5TRACE4("e", "*xii**x", obj, plugin_id, dxpl_id, req);
 
     /* Check args and get class pointer */
-    if(NULL == grp)
+    if(NULL == obj)
         HGOTO_ERROR(H5E_ARGS, H5E_BADVALUE, FAIL, "invalid object")
     if(NULL == (cls = (H5VL_class_t *)H5I_object_verify(plugin_id, H5I_VOL)))
         HGOTO_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "not a VOL plugin ID")
 
     /* Call the corresponding internal VOL routine */
-    if(H5VL_group_close(grp, cls, dxpl_id, req) < 0)
+    if(H5VL__group_close(obj, cls, dxpl_id, req) < 0)
         HGOTO_ERROR(H5E_VOL, H5E_CANTCLOSEOBJ, FAIL, "unable to close group")
 
 done:
diff --git a/src/H5VLprivate.h b/src/H5VLprivate.h
index 1e91523..fab4bbf 100644
--- a/src/H5VLprivate.h
+++ b/src/H5VLprivate.h
@@ -131,12 +131,12 @@ H5_DLL herr_t H5VL_file_optional(const H5VL_object_t *vol_obj, hid_t dxpl_id, vo
 H5_DLL herr_t H5VL_file_close(const H5VL_object_t *vol_obj, hid_t dxpl_id, void **req);
 
 /* Group functions */
-H5_DLL void *H5VL_group_create(void *obj, H5VL_loc_params_t loc_params, const H5VL_class_t *cls, const char *name, hid_t gcpl_id, hid_t gapl_id, hid_t dxpl_id, void **req);
-H5_DLL void *H5VL_group_open(void *obj, H5VL_loc_params_t loc_params, const H5VL_class_t *cls, const char *name, hid_t gapl_id, hid_t dxpl_id, void **req);
-H5_DLL herr_t H5VL_group_get(void *obj, const H5VL_class_t *cls, H5VL_group_get_t get_type, hid_t dxpl_id, void **req, ...);
-H5_DLL herr_t H5VL_group_specific(void *obj, const H5VL_class_t *cls, H5VL_group_specific_t specific_type, hid_t dxpl_id, void **req, ...);
-H5_DLL herr_t H5VL_group_optional(void *obj, const H5VL_class_t *cls, hid_t dxpl_id, void **req, ...);
-H5_DLL herr_t H5VL_group_close(void *grp, const H5VL_class_t *cls, hid_t dxpl_id, void **req);
+H5_DLL void *H5VL_group_create(const H5VL_object_t *vol_obj, H5VL_loc_params_t loc_params, const char *name, hid_t gcpl_id, hid_t gapl_id, hid_t dxpl_id, void **req);
+H5_DLL void * H5VL_group_open(const H5VL_object_t *vol_obj, H5VL_loc_params_t loc_params, const char *name, hid_t gapl_id, hid_t dxpl_id, void **req);
+H5_DLL herr_t H5VL_group_get(const H5VL_object_t *vol_obj, H5VL_group_get_t get_type, hid_t dxpl_id, void **req, ...);
+H5_DLL herr_t H5VL_group_specific(const H5VL_object_t *vol_obj, H5VL_group_specific_t specific_type, hid_t dxpl_id, void **req, ...);
+H5_DLL herr_t H5VL_group_optional(const H5VL_object_t *vol_obj, hid_t dxpl_id, void **req, ...);
+H5_DLL herr_t H5VL_group_close(const H5VL_object_t *vol_obj, hid_t dxpl_id, void **req);
 
 /* Link functions */
 H5_DLL herr_t H5VL_link_create(H5VL_link_create_type_t create_type, void *obj, H5VL_loc_params_t loc_params, const H5VL_class_t *cls, hid_t lcpl_id, hid_t lapl_id, hid_t dxpl_id, void **req);