Refactor and standarize file object callbacks, including some fixes on the

dataset callbacks.

7 files changed, 312 insertions, 212 deletions

diff --git a/src/H5Dio.c b/src/H5Dio.c
index ed43f8f..f977b0e 100644
--- a/src/H5Dio.c
+++ b/src/H5Dio.c
@@ -242,7 +242,7 @@ H5Dread_chunk(hid_t dset_id, hid_t dxpl_id, const hsize_t *offset, uint32_t *fil
     H5CX_set_dxpl(dxpl_id);
 
     /* Read the raw chunk */
-    if (H5VL_dataset_optional(vol_obj, dxpl_id, H5_REQUEST_NULL, H5VL_DATASET_CHUNK_READ, offset, filters, buf) < 0)
+    if(H5VL_dataset_optional(vol_obj, dxpl_id, H5_REQUEST_NULL, H5VL_DATASET_CHUNK_READ, offset, filters, buf) < 0)
         HGOTO_ERROR(H5E_DATASET, H5E_READERROR, FAIL, "can't read unprocessed chunk data")
 
 done:
@@ -370,7 +370,7 @@ H5Dwrite_chunk(hid_t dset_id, hid_t dxpl_id, uint32_t filters, const hsize_t *of
     H5CX_set_dxpl(dxpl_id);
 
     /* Write chunk */
-    if (H5VL_dataset_optional(vol_obj, dxpl_id, H5_REQUEST_NULL, H5VL_DATASET_CHUNK_WRITE, filters, offset, data_size_32, buf) < 0)
+    if(H5VL_dataset_optional(vol_obj, dxpl_id, H5_REQUEST_NULL, H5VL_DATASET_CHUNK_WRITE, filters, offset, data_size_32, buf) < 0)
         HGOTO_ERROR(H5E_DATASET, H5E_WRITEERROR, FAIL, "can't write unprocessed chunk data")
 
 done:
diff --git a/src/H5F.c b/src/H5F.c
index 75d6c04..ffa2d9a 100644
--- a/src/H5F.c
+++ b/src/H5F.c
@@ -199,7 +199,7 @@ H5F__close_cb(H5VL_object_t *file_vol_obj)
     HDassert(file_vol_obj);
 
     /* Close the file */
-    if(H5VL_file_close(file_vol_obj->data, file_vol_obj->plugin->cls, H5P_DATASET_XFER_DEFAULT, H5_REQUEST_NULL) < 0)
+    if(H5VL_file_close(file_vol_obj, H5P_DATASET_XFER_DEFAULT, H5_REQUEST_NULL) < 0)
         HGOTO_ERROR(H5E_FILE, H5E_CANTCLOSEFILE, FAIL, "unable to close file");
 
     /* Free the VOL object */
@@ -239,8 +239,7 @@ H5Fget_create_plist(hid_t file_id)
         HGOTO_ERROR(H5E_ARGS, H5E_BADTYPE, H5I_INVALID_HID, "invalid file identifier")
 
     /* Retrieve the file creation property list */
-    if(H5VL_file_get(vol_obj->data, vol_obj->plugin->cls, H5VL_FILE_GET_FCPL, 
-                     H5P_DATASET_XFER_DEFAULT, H5_REQUEST_NULL, &ret_value) < 0)
+    if(H5VL_file_get(vol_obj, H5VL_FILE_GET_FCPL, H5P_DATASET_XFER_DEFAULT, H5_REQUEST_NULL, &ret_value) < 0)
         HGOTO_ERROR(H5E_PLIST, H5E_CANTCOPY, H5I_INVALID_HID, "unable to retrieve file creation properties")
 
 done:
@@ -280,8 +279,7 @@ H5Fget_access_plist(hid_t file_id)
         HGOTO_ERROR(H5E_ARGS, H5E_BADTYPE, H5I_INVALID_HID, "invalid file identifier")
 
     /* Retrieve the file's access property list */
-    if(H5VL_file_get(vol_obj->data, vol_obj->plugin->cls, H5VL_FILE_GET_FAPL, 
-                     H5P_DATASET_XFER_DEFAULT, H5_REQUEST_NULL, &ret_value) < 0)
+    if(H5VL_file_get(vol_obj, H5VL_FILE_GET_FAPL, H5P_DATASET_XFER_DEFAULT, H5_REQUEST_NULL, &ret_value) < 0)
         HGOTO_ERROR(H5E_PLIST, H5E_CANTGET, H5I_INVALID_HID, "can't get file access property list")
 
 done:
@@ -350,8 +348,7 @@ H5Fget_obj_count(hid_t file_id, unsigned types)
             HGOTO_ERROR(H5E_ARGS, H5E_BADTYPE, (-1), "not a file id")
 
         /* Get the count */
-        if(H5VL_file_get(vol_obj->data, vol_obj->plugin->cls, H5VL_FILE_GET_OBJ_COUNT, 
-                         H5P_DATASET_XFER_DEFAULT, H5_REQUEST_NULL, types, &ret_value) < 0)
+        if(H5VL_file_get(vol_obj, H5VL_FILE_GET_OBJ_COUNT, H5P_DATASET_XFER_DEFAULT, H5_REQUEST_NULL, types, &ret_value) < 0)
             HGOTO_ERROR(H5E_FILE, H5E_CANTGET, (-1), "unable to get object count in file(s)")
     }
     /* If we passed in the 'special' ID, get the count for everything open in the
@@ -462,8 +459,7 @@ H5Fget_obj_ids(hid_t file_id, unsigned types, size_t max_objs, hid_t *oid_list)
             HGOTO_ERROR(H5E_ARGS, H5E_BADTYPE, (-1), "invalid file identifier")
 
         /* Get the IDs */
-        if(H5VL_file_get(vol_obj->data, vol_obj->plugin->cls, H5VL_FILE_GET_OBJ_IDS, 
-                         H5P_DATASET_XFER_DEFAULT, H5_REQUEST_NULL, types, max_objs, oid_list, &ret_value) < 0)
+        if(H5VL_file_get(vol_obj, H5VL_FILE_GET_OBJ_IDS, H5P_DATASET_XFER_DEFAULT, H5_REQUEST_NULL, types, max_objs, oid_list, &ret_value) < 0)
             HGOTO_ERROR(H5E_FILE, H5E_CANTGET, (-1), "unable to get object ids in file(s)")
     } /* end if */
     /* If we passed in the 'special' ID, get the count for everything open in the
@@ -536,7 +532,7 @@ H5Fget_vfd_handle(hid_t file_id, hid_t fapl_id, void **file_handle)
         HGOTO_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "invalid file identifier")
 
     /* Retrieve the VFD handle for the file */
-    if(H5VL_file_optional(vol_obj->data, vol_obj->plugin->cls, H5P_DATASET_XFER_DEFAULT, H5_REQUEST_NULL, H5VL_FILE_GET_VFD_HANDLE, file_handle, fapl_id) < 0)
+    if(H5VL_file_optional(vol_obj, H5P_DATASET_XFER_DEFAULT, H5_REQUEST_NULL, H5VL_FILE_GET_VFD_HANDLE, file_handle, fapl_id) < 0)
         HGOTO_ERROR(H5E_FILE, H5E_CANTGET, FAIL, "unable to get VFD handle")
 
 done:
@@ -573,7 +569,7 @@ H5Fis_accessible(const char *name, hid_t fapl_id)
             HGOTO_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "not file access property list")
 
     /* Check if file is accessible */
-    if(H5VL_file_specific(NULL, NULL, H5VL_FILE_IS_ACCESSIBLE, H5P_DATASET_XFER_DEFAULT, H5_REQUEST_NULL, fapl_id, name, &ret_value) < 0)
+    if(H5VL_file_specific(NULL, H5VL_FILE_IS_ACCESSIBLE, H5P_DATASET_XFER_DEFAULT, H5_REQUEST_NULL, fapl_id, name, &ret_value) < 0)
         HGOTO_ERROR(H5E_FILE, H5E_NOTHDF5, FAIL, "unable to determine if file is accessible as HDF5")
 
 done:
@@ -776,7 +772,7 @@ H5Fflush(hid_t object_id, H5F_scope_t scope)
         HGOTO_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "invalid object identifier")
 
     /* Flush the object */
-    if(H5VL_file_specific(vol_obj->data, vol_obj->plugin->cls, H5VL_FILE_FLUSH, H5P_DATASET_XFER_DEFAULT, H5_REQUEST_NULL, obj_type, scope) < 0)
+    if(H5VL_file_specific(vol_obj, H5VL_FILE_FLUSH, H5P_DATASET_XFER_DEFAULT, H5_REQUEST_NULL, obj_type, scope) < 0)
         HGOTO_ERROR(H5E_FILE, H5E_CANTFLUSH, FAIL, "unable to flush file")
 
 done:
@@ -851,7 +847,7 @@ H5Freopen(hid_t file_id)
         HGOTO_ERROR(H5E_ARGS, H5E_BADTYPE, H5I_INVALID_HID, "invalid file identifier")
 
     /* Reopen the file */
-    if(H5VL_file_specific(vol_obj->data, vol_obj->plugin->cls, H5VL_FILE_REOPEN, H5P_DATASET_XFER_DEFAULT, H5_REQUEST_NULL, &file) < 0)
+    if(H5VL_file_specific(vol_obj, H5VL_FILE_REOPEN, H5P_DATASET_XFER_DEFAULT, H5_REQUEST_NULL, &file) < 0)
         HGOTO_ERROR(H5E_FILE, H5E_CANTINIT, H5I_INVALID_HID, "unable to reopen file via the VOL plugin")
 
     /* Make sure that worked */
@@ -895,7 +891,7 @@ H5Fget_intent(hid_t file_id, unsigned *intent_flags)
             HGOTO_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "invalid file identifier")
 
         /* Get the flags */
-        if((ret_value = H5VL_file_get(vol_obj->data, vol_obj->plugin->cls, H5VL_FILE_GET_INTENT, H5P_DATASET_XFER_DEFAULT, H5_REQUEST_NULL, intent_flags)) < 0)
+        if((ret_value = H5VL_file_get(vol_obj, H5VL_FILE_GET_INTENT, H5P_DATASET_XFER_DEFAULT, H5_REQUEST_NULL, intent_flags)) < 0)
             HGOTO_ERROR(H5E_FILE, H5E_CANTGET, FAIL, "unable to get file's intent flags")
     } /* end if */
 
@@ -929,7 +925,7 @@ H5Fget_freespace(hid_t file_id)
         HGOTO_ERROR(H5E_ARGS, H5E_BADTYPE, (-1), "invalid file identifier")
 
     /* Get the amount of free space in the file */
-    if(H5VL_file_optional(vol_obj->data, vol_obj->plugin->cls, H5P_DATASET_XFER_DEFAULT, H5_REQUEST_NULL, H5VL_FILE_GET_FREE_SPACE, &ret_value) < 0)
+    if(H5VL_file_optional(vol_obj, H5P_DATASET_XFER_DEFAULT, H5_REQUEST_NULL, H5VL_FILE_GET_FREE_SPACE, &ret_value) < 0)
         HGOTO_ERROR(H5E_FILE, H5E_CANTGET, (-1), "unable to get file free space")
 
 done:
@@ -964,7 +960,7 @@ H5Fget_filesize(hid_t file_id, hsize_t *size)
         HGOTO_ERROR(H5E_ARGS, H5E_BADVALUE, FAIL, "not a file ID")
 
     /* Get the file size */
-    if(H5VL_file_optional(vol_obj->data, vol_obj->plugin->cls, H5P_DATASET_XFER_DEFAULT, H5_REQUEST_NULL, H5VL_FILE_GET_SIZE, size) < 0)
+    if(H5VL_file_optional(vol_obj, H5P_DATASET_XFER_DEFAULT, H5_REQUEST_NULL, H5VL_FILE_GET_SIZE, size) < 0)
         HGOTO_ERROR(H5E_FILE, H5E_CANTGET, FAIL, "unable to get file size")
 
 done:
@@ -1025,7 +1021,7 @@ H5Fget_file_image(hid_t file_id, void *buf_ptr, size_t buf_len)
         HGOTO_ERROR(H5E_ARGS, H5E_BADVALUE, (-1), "not a file ID")
 
     /* Get the file image */
-    if(H5VL_file_optional(vol_obj->data, vol_obj->plugin->cls, H5P_DATASET_XFER_DEFAULT, H5_REQUEST_NULL, H5VL_FILE_GET_FILE_IMAGE, buf_ptr, &ret_value, buf_len) < 0)
+    if(H5VL_file_optional(vol_obj, H5P_DATASET_XFER_DEFAULT, H5_REQUEST_NULL, H5VL_FILE_GET_FILE_IMAGE, buf_ptr, &ret_value, buf_len) < 0)
         HGOTO_ERROR(H5E_FILE, H5E_CANTGET, (-1), "unable to get file image")
 
 done:
@@ -1065,7 +1061,7 @@ H5Fget_mdc_config(hid_t file_id, H5AC_cache_config_t *config_ptr)
         HGOTO_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "invalid file identifier")
 
     /* Get the metadata cache configuration */
-    if(H5VL_file_optional(vol_obj->data, vol_obj->plugin->cls, H5P_DATASET_XFER_DEFAULT, H5_REQUEST_NULL, H5VL_FILE_GET_MDC_CONF, config_ptr) < 0)
+    if(H5VL_file_optional(vol_obj, H5P_DATASET_XFER_DEFAULT, H5_REQUEST_NULL, H5VL_FILE_GET_MDC_CONF, config_ptr) < 0)
         HGOTO_ERROR(H5E_FILE, H5E_CANTGET, FAIL, "unable to get metadata cache configuration")
 
 done:
@@ -1098,8 +1094,7 @@ H5Fset_mdc_config(hid_t file_id, H5AC_cache_config_t *config_ptr)
         HGOTO_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "invalid file identifier")
 
     /* Set the metadata cache configuration  */
-    if(H5VL_file_optional(vol_obj->data, vol_obj->plugin->cls, H5P_DATASET_XFER_DEFAULT, 
-                          H5_REQUEST_NULL, H5VL_FILE_SET_MDC_CONFIG, config_ptr) < 0)
+    if(H5VL_file_optional(vol_obj, H5P_DATASET_XFER_DEFAULT, H5_REQUEST_NULL, H5VL_FILE_SET_MDC_CONFIG, config_ptr) < 0)
         HGOTO_ERROR(H5E_FILE, H5E_CANTSET, FAIL, "unable to set metadata cache configuration")
 
 done:
@@ -1135,7 +1130,7 @@ H5Fget_mdc_hit_rate(hid_t file_id, double *hit_rate_ptr)
         HGOTO_ERROR(H5E_ARGS, H5E_BADVALUE, FAIL, "not a file ID")
 
     /* Get the current hit rate */
-    if(H5VL_file_optional(vol_obj->data, vol_obj->plugin->cls, H5P_DATASET_XFER_DEFAULT, H5_REQUEST_NULL, H5VL_FILE_GET_MDC_HR, hit_rate_ptr) < 0)
+    if(H5VL_file_optional(vol_obj, H5P_DATASET_XFER_DEFAULT, H5_REQUEST_NULL, H5VL_FILE_GET_MDC_HR, hit_rate_ptr) < 0)
         HGOTO_ERROR(H5E_FILE, H5E_CANTGET, FAIL, "unable to get MDC hit rate")
 
 done:
@@ -1172,7 +1167,7 @@ H5Fget_mdc_size(hid_t file_id, size_t *max_size_ptr, size_t *min_clean_size_ptr,
          HGOTO_ERROR(H5E_ARGS, H5E_BADVALUE, FAIL, "not a file ID")
 
     /* Get the size data */
-    if(H5VL_file_optional(vol_obj->data, vol_obj->plugin->cls, H5P_DATASET_XFER_DEFAULT, H5_REQUEST_NULL, H5VL_FILE_GET_MDC_SIZE, max_size_ptr, min_clean_size_ptr, cur_size_ptr, cur_num_entries_ptr) < 0)
+    if(H5VL_file_optional(vol_obj, H5P_DATASET_XFER_DEFAULT, H5_REQUEST_NULL, H5VL_FILE_GET_MDC_SIZE, max_size_ptr, min_clean_size_ptr, cur_size_ptr, cur_num_entries_ptr) < 0)
         HGOTO_ERROR(H5E_FILE, H5E_CANTGET, FAIL, "unable to get MDC size")
 
 done:
@@ -1210,7 +1205,7 @@ H5Freset_mdc_hit_rate_stats(hid_t file_id)
         HGOTO_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "invalid file identifier")
 
     /* Reset the hit rate statistic */
-    if(H5VL_file_optional(vol_obj->data, vol_obj->plugin->cls, H5P_DATASET_XFER_DEFAULT, H5_REQUEST_NULL, H5VL_FILE_RESET_MDC_HIT_RATE) < 0)
+    if(H5VL_file_optional(vol_obj, H5P_DATASET_XFER_DEFAULT, H5_REQUEST_NULL, H5VL_FILE_RESET_MDC_HIT_RATE) < 0)
         HGOTO_ERROR(H5E_FILE, H5E_CANTSET, FAIL, "can't reset cache hit rate")
 
 done:
@@ -1259,7 +1254,7 @@ H5Fget_name(hid_t obj_id, char *name/*out*/, size_t size)
         HGOTO_ERROR(H5E_ARGS, H5E_BADTYPE, (-1), "invalid file identifier")
 
     /* Get the filename via the VOL */
-    if(H5VL_file_get(vol_obj->data, vol_obj->plugin->cls, H5VL_FILE_GET_NAME, H5P_DATASET_XFER_DEFAULT, H5_REQUEST_NULL, type, size, name, &ret_value) < 0)
+    if(H5VL_file_get(vol_obj, H5VL_FILE_GET_NAME, H5P_DATASET_XFER_DEFAULT, H5_REQUEST_NULL, type, size, name, &ret_value) < 0)
         HGOTO_ERROR(H5E_FILE, H5E_CANTGET, (-1), "unable to get file name")
 
 done:
@@ -1304,7 +1299,7 @@ H5Fget_info2(hid_t obj_id, H5F_info2_t *finfo)
         HGOTO_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "invalid object identifier")
 
     /* Get the file information */
-    if(H5VL_file_optional(vol_obj->data, vol_obj->plugin->cls, H5P_DATASET_XFER_DEFAULT, H5_REQUEST_NULL, H5VL_FILE_GET_INFO, type, finfo) < 0)
+    if(H5VL_file_optional(vol_obj, H5P_DATASET_XFER_DEFAULT, H5_REQUEST_NULL, H5VL_FILE_GET_INFO, type, finfo) < 0)
         HGOTO_ERROR(H5E_FILE, H5E_CANTGET, FAIL, "unable to retrieve file info")
 
 done:
@@ -1340,7 +1335,7 @@ H5Fget_metadata_read_retry_info(hid_t file_id, H5F_retry_info_t *info)
         HGOTO_ERROR(H5E_ARGS, H5E_BADVALUE, FAIL, "not a file ID")
 
     /* Get the retry info */
-    if(H5VL_file_optional(vol_obj->data, vol_obj->plugin->cls, H5P_DATASET_XFER_DEFAULT, H5_REQUEST_NULL, H5VL_FILE_GET_METADATA_READ_RETRY_INFO, info) < 0)
+    if(H5VL_file_optional(vol_obj, H5P_DATASET_XFER_DEFAULT, H5_REQUEST_NULL, H5VL_FILE_GET_METADATA_READ_RETRY_INFO, info) < 0)
         HGOTO_ERROR(H5E_FILE, H5E_CANTRELEASE, FAIL, "can't get metadata read retry info")
 
 done:
@@ -1379,7 +1374,7 @@ H5Fget_free_sections(hid_t file_id, H5F_mem_t type, size_t nsects,
         HGOTO_ERROR(H5E_ARGS, H5E_BADVALUE, (-1), "nsects must be > 0")
 
     /* Get the free-space section information in the file */
-    if(H5VL_file_optional(vol_obj->data, vol_obj->plugin->cls, H5P_DATASET_XFER_DEFAULT, H5_REQUEST_NULL, H5VL_FILE_GET_FREE_SECTIONS, sect_info, &ret_value, type, nsects) < 0)
+    if(H5VL_file_optional(vol_obj, H5P_DATASET_XFER_DEFAULT, H5_REQUEST_NULL, H5VL_FILE_GET_FREE_SECTIONS, sect_info, &ret_value, type, nsects) < 0)
         HGOTO_ERROR(H5E_FILE, H5E_CANTGET, (-1), "unable to get file free sections")
 
 done:
@@ -1412,7 +1407,7 @@ H5Fclear_elink_file_cache(hid_t file_id)
         HGOTO_ERROR(H5E_ARGS, H5E_BADVALUE, FAIL, "not a file ID")
 
     /* Release the EFC */
-    if(H5VL_file_optional(vol_obj->data, vol_obj->plugin->cls, H5P_DATASET_XFER_DEFAULT, H5_REQUEST_NULL, H5VL_FILE_CLEAR_ELINK_CACHE) < 0)
+    if(H5VL_file_optional(vol_obj, H5P_DATASET_XFER_DEFAULT, H5_REQUEST_NULL, H5VL_FILE_CLEAR_ELINK_CACHE) < 0)
         HGOTO_ERROR(H5E_FILE, H5E_CANTRELEASE, FAIL, "can't release external file cache")
 
 done:
@@ -1472,7 +1467,7 @@ H5Fstart_swmr_write(hid_t file_id)
         HGOTO_ERROR(H5E_FILE, H5E_CANTSET, FAIL, "can't set collective metadata read info")
 
     /* Start SWMR writing */
-    if(H5VL_file_optional(vol_obj->data, vol_obj->plugin->cls, H5P_DATASET_XFER_DEFAULT, H5_REQUEST_NULL, H5VL_FILE_START_SWMR_WRITE) < 0)
+    if(H5VL_file_optional(vol_obj, H5P_DATASET_XFER_DEFAULT, H5_REQUEST_NULL, H5VL_FILE_START_SWMR_WRITE) < 0)
         HGOTO_ERROR(H5E_FILE, H5E_SYSTEM, FAIL, "unable to start SWMR writing")
 
 done:
@@ -1504,8 +1499,7 @@ H5Fstart_mdc_logging(hid_t file_id)
         HGOTO_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "hid_t identifier is not a file ID")
 
     /* Call mdc logging function */
-    if(H5VL_file_optional(vol_obj->data, vol_obj->plugin->cls, H5P_DATASET_XFER_DEFAULT, 
-                          H5_REQUEST_NULL, H5VL_FILE_START_MDC_LOGGING) < 0)
+    if(H5VL_file_optional(vol_obj, H5P_DATASET_XFER_DEFAULT, H5_REQUEST_NULL, H5VL_FILE_START_MDC_LOGGING) < 0)
         HGOTO_ERROR(H5E_FILE, H5E_LOGFAIL, FAIL, "unable to start mdc logging")
 
 done:
@@ -1538,7 +1532,7 @@ H5Fstop_mdc_logging(hid_t file_id)
         HGOTO_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "hid_t identifier is not a file ID")
 
     /* Call mdc logging function */
-    if(H5VL_file_optional(vol_obj->data, vol_obj->plugin->cls, H5P_DATASET_XFER_DEFAULT, H5_REQUEST_NULL, H5VL_FILE_STOP_MDC_LOGGING) < 0)
+    if(H5VL_file_optional(vol_obj, H5P_DATASET_XFER_DEFAULT, H5_REQUEST_NULL, H5VL_FILE_STOP_MDC_LOGGING) < 0)
         HGOTO_ERROR(H5E_FILE, H5E_LOGFAIL, FAIL, "unable to stop mdc logging")
 
 done:
@@ -1572,7 +1566,7 @@ H5Fget_mdc_logging_status(hid_t file_id, hbool_t *is_enabled,
         HGOTO_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "hid_t identifier is not a file ID")
 
     /* Call mdc logging function */
-    if(H5VL_file_optional(vol_obj->data, vol_obj->plugin->cls, H5P_DATASET_XFER_DEFAULT, H5_REQUEST_NULL, H5VL_FILE_GET_MDC_LOGGING_STATUS, is_enabled, is_currently_logging) < 0)
+    if(H5VL_file_optional(vol_obj, H5P_DATASET_XFER_DEFAULT, H5_REQUEST_NULL, H5VL_FILE_GET_MDC_LOGGING_STATUS, is_enabled, is_currently_logging) < 0)
         HGOTO_ERROR(H5E_FILE, H5E_LOGFAIL, FAIL, "unable to get logging status")
 
 done:
@@ -1610,7 +1604,7 @@ H5Fset_libver_bounds(hid_t file_id, H5F_libver_t low, H5F_libver_t high)
         HGOTO_ERROR(H5E_FILE, H5E_CANTSET, FAIL, "can't set collective metadata read info")
 
     /* Set the library's version bounds */
-    if(H5VL_file_optional(vol_obj->data, vol_obj->plugin->cls, H5P_DATASET_XFER_DEFAULT, H5_REQUEST_NULL, H5VL_FILE_SET_LIBVER_BOUNDS, low, high) < 0)
+    if(H5VL_file_optional(vol_obj, H5P_DATASET_XFER_DEFAULT, H5_REQUEST_NULL, H5VL_FILE_SET_LIBVER_BOUNDS, low, high) < 0)
         HGOTO_ERROR(H5E_FILE, H5E_CANTSET, FAIL, "can't set library version bounds")
 
 done:
@@ -1647,7 +1641,7 @@ H5Fformat_convert(hid_t file_id)
         HGOTO_ERROR(H5E_FILE, H5E_CANTSET, FAIL, "can't set collective metadata read info")
 
     /* Convert the format */
-    if(H5VL_file_optional(vol_obj->data, vol_obj->plugin->cls, H5P_DATASET_XFER_DEFAULT, H5_REQUEST_NULL, H5VL_FILE_FORMAT_CONVERT) < 0)
+    if(H5VL_file_optional(vol_obj, H5P_DATASET_XFER_DEFAULT, H5_REQUEST_NULL, H5VL_FILE_FORMAT_CONVERT) < 0)
         HGOTO_ERROR(H5E_FILE, H5E_CANTCONVERT, FAIL, "can't convert file format")
 
 done:
@@ -1678,7 +1672,7 @@ H5Freset_page_buffering_stats(hid_t file_id)
         HGOTO_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "invalid file identifier")
 
     /* Reset the statistics */
-    if(H5VL_file_optional(vol_obj->data, vol_obj->plugin->cls, H5P_DATASET_XFER_DEFAULT, H5_REQUEST_NULL, H5VL_FILE_RESET_PAGE_BUFFERING_STATS) < 0)
+    if(H5VL_file_optional(vol_obj, H5P_DATASET_XFER_DEFAULT, H5_REQUEST_NULL, H5VL_FILE_RESET_PAGE_BUFFERING_STATS) < 0)
         HGOTO_ERROR(H5E_FILE, H5E_CANTSET, FAIL, "can't reset stats for page buffering")
 
 done:
@@ -1713,7 +1707,7 @@ H5Fget_page_buffering_stats(hid_t file_id, unsigned accesses[2], unsigned hits[2
         HGOTO_ERROR(H5E_ARGS, H5E_BADVALUE, FAIL, "NULL input parameters for stats")
 
     /* Get the statistics */
-    if(H5VL_file_optional(vol_obj->data, vol_obj->plugin->cls, H5P_DATASET_XFER_DEFAULT, H5_REQUEST_NULL, H5VL_FILE_GET_PAGE_BUFFERING_STATS, accesses, hits, misses, evictions, bypasses) < 0)
+    if(H5VL_file_optional(vol_obj, H5P_DATASET_XFER_DEFAULT, H5_REQUEST_NULL, H5VL_FILE_GET_PAGE_BUFFERING_STATS, accesses, hits, misses, evictions, bypasses) < 0)
         HGOTO_ERROR(H5E_FILE, H5E_CANTGET, FAIL, "can't retrieve stats for page buffering")
 
 done:
@@ -1748,7 +1742,7 @@ H5Fget_mdc_image_info(hid_t file_id, haddr_t *image_addr, hsize_t *image_len)
         HGOTO_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "hid_t identifier is not a file ID")
 
     /* Go get the address and size of the cache image */
-    if(H5VL_file_optional(vol_obj->data, vol_obj->plugin->cls, H5P_DATASET_XFER_DEFAULT, H5_REQUEST_NULL, H5VL_FILE_GET_MDC_IMAGE_INFO, image_addr, image_len) < 0)
+    if(H5VL_file_optional(vol_obj, H5P_DATASET_XFER_DEFAULT, H5_REQUEST_NULL, H5VL_FILE_GET_MDC_IMAGE_INFO, image_addr, image_len) < 0)
         HGOTO_ERROR(H5E_FILE, H5E_CANTGET, FAIL, "can't retrieve cache image info")
 
 done:
@@ -1782,7 +1776,7 @@ H5Fget_eoa(hid_t file_id, haddr_t *eoa)
     /* Only do work if valid pointer to fill in */
     if(eoa) {
         /* Retrieve the EOA for the file */
-        if(H5VL_file_optional(vol_obj->data, vol_obj->plugin->cls, H5P_DATASET_XFER_DEFAULT, H5_REQUEST_NULL, H5VL_FILE_GET_EOA, eoa) < 0)
+        if(H5VL_file_optional(vol_obj, H5P_DATASET_XFER_DEFAULT, H5_REQUEST_NULL, H5VL_FILE_GET_EOA, eoa) < 0)
             HGOTO_ERROR(H5E_FILE, H5E_CANTGET, FAIL, "unable to get EOA")
     } /* end if */
 
@@ -1813,7 +1807,7 @@ H5Fincrement_filesize(hid_t file_id, hsize_t increment)
         HGOTO_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "hid_t identifier is not a file ID")
 
     /* Increment the file size */
-    if(H5VL_file_optional(vol_obj->data, vol_obj->plugin->cls, H5P_DATASET_XFER_DEFAULT, H5_REQUEST_NULL, H5VL_FILE_INCR_FILESIZE, increment) < 0)
+    if(H5VL_file_optional(vol_obj, H5P_DATASET_XFER_DEFAULT, H5_REQUEST_NULL, H5VL_FILE_INCR_FILESIZE, increment) < 0)
         HGOTO_ERROR(H5E_FILE, H5E_CANTSET, FAIL, "unable to increment file size")
 
 done:
diff --git a/src/H5Fdeprec.c b/src/H5Fdeprec.c
index da47e45..dfc1441 100644
--- a/src/H5Fdeprec.c
+++ b/src/H5Fdeprec.c
@@ -118,7 +118,7 @@ H5Fget_info1(hid_t obj_id, H5F_info1_t *finfo)
         HGOTO_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "invalid object identifier")
 
     /* Get the file information */
-    if(H5VL_file_optional(vol_obj->data, vol_obj->plugin->cls, H5P_DATASET_XFER_DEFAULT, H5_REQUEST_NULL, H5VL_FILE_GET_INFO, type, &finfo2) < 0)
+    if(H5VL_file_optional(vol_obj, H5P_DATASET_XFER_DEFAULT, H5_REQUEST_NULL, H5VL_FILE_GET_INFO, type, &finfo2) < 0)
         HGOTO_ERROR(H5E_FILE, H5E_CANTGET, FAIL, "unable to retrieve file info")
 
     /* Copy the compatible fields into the older struct */
@@ -157,7 +157,7 @@ H5Fis_hdf5(const char *name)
         HGOTO_ERROR(H5E_ARGS, H5E_BADRANGE, (-1), "no file name specified")
 
     /* Check if file is accessible */
-    if(H5VL_file_specific(NULL, NULL, H5VL_FILE_IS_ACCESSIBLE, H5P_DATASET_XFER_DEFAULT, H5_REQUEST_NULL, H5P_FILE_ACCESS_DEFAULT, name, &ret_value) < 0)
+    if(H5VL_file_specific(NULL, H5VL_FILE_IS_ACCESSIBLE, H5P_DATASET_XFER_DEFAULT, H5_REQUEST_NULL, H5P_FILE_ACCESS_DEFAULT, name, &ret_value) < 0)
         HGOTO_ERROR(H5E_FILE, H5E_NOTHDF5, (-1), "unable to determine if file is accessible as HDF5")
 
 done:
@@ -225,7 +225,7 @@ H5Fset_latest_format(hid_t file_id, hbool_t latest_format)
         low = H5F_LIBVER_EARLIEST;
 
     /* Set the library's version bounds */
-    if(H5VL_file_optional(vol_obj->data, vol_obj->plugin->cls, H5P_DATASET_XFER_DEFAULT, H5_REQUEST_NULL, H5VL_FILE_SET_LIBVER_BOUNDS, low, high) < 0)
+    if(H5VL_file_optional(vol_obj, H5P_DATASET_XFER_DEFAULT, H5_REQUEST_NULL, H5VL_FILE_SET_LIBVER_BOUNDS, low, high) < 0)
         HGOTO_ERROR(H5E_FILE, H5E_CANTSET, FAIL, "can't set library version bounds")
 
 done:
diff --git a/src/H5Fint.c b/src/H5Fint.c
index 0e35bea..fe387a5 100644
--- a/src/H5Fint.c
+++ b/src/H5Fint.c
@@ -3529,14 +3529,8 @@ H5F_get_file_id(hid_t obj_id, H5I_type_t type)
     if(NULL == (vol_obj = H5VL_vol_object(obj_id)))
         HGOTO_ERROR(H5E_ARGS, H5E_BADTYPE, H5I_INVALID_HID, "invalid identifier")
 
-    /* Set wrapper info in API context */
-    if(H5VL_set_vol_wrapper(vol_obj->data, vol_obj->plugin) < 0)
-        HGOTO_ERROR(H5E_FILE, H5E_CANTSET, H5I_INVALID_HID, "can't set VOL wrapper info")
-    vol_wrapper_set = TRUE;
-
     /* Get the file through the VOL */
-    if(H5VL_file_optional(vol_obj->data, vol_obj->plugin->cls, H5P_DATASET_XFER_DEFAULT,
-            H5_REQUEST_NULL, H5VL_FILE_GET_FILE, type, &file) < 0)
+    if(H5VL_file_optional(vol_obj, H5P_DATASET_XFER_DEFAULT, H5_REQUEST_NULL, H5VL_FILE_GET_FILE, type, &file) < 0)
         HGOTO_ERROR(H5E_FILE, H5E_CANTINIT, H5I_INVALID_HID, "unable to get file")
     if(NULL == file)
         HGOTO_ERROR(H5E_FILE, H5E_CANTINIT, H5I_INVALID_HID, "unable to get the file through the VOL")
@@ -3547,6 +3541,11 @@ H5F_get_file_id(hid_t obj_id, H5I_type_t type)
 
     /* If the ID does not exist, register it with the VOL plugin */
     if(H5I_INVALID_HID == ret_value) {
+        /* Set wrapper info in API context */
+        if(H5VL_set_vol_wrapper(vol_obj->data, vol_obj->plugin) < 0)
+            HGOTO_ERROR(H5E_FILE, H5E_CANTSET, H5I_INVALID_HID, "can't set VOL wrapper info")
+        vol_wrapper_set = TRUE;
+
 {
 void *vol_wrap_ctx = NULL;       /* Object wrapping context */
 
diff --git a/src/H5Fmount.c b/src/H5Fmount.c
index 0e3c06d..4a67cc2 100644
--- a/src/H5Fmount.c
+++ b/src/H5Fmount.c
@@ -443,7 +443,6 @@ H5Fmount(hid_t loc_id, const char *name, hid_t child_id, hid_t plist_id)
     H5VL_object_t  *child_vol_obj = NULL;       /* Child object         */
     H5I_type_t      loc_type;                   /* ID type of location  */
     H5I_type_t      child_type;                 /* ID type of child     */
-    hbool_t         vol_wrapper_set = FALSE;            /* Whether the VOL object wrapping context was set up */
     herr_t          ret_value = SUCCEED;        /* Return value         */
 
     FUNC_ENTER_API(FAIL)
@@ -482,21 +481,11 @@ H5Fmount(hid_t loc_id, const char *name, hid_t child_id, hid_t plist_id)
     if(loc_vol_obj->plugin->cls->value != child_vol_obj->plugin->cls->value)
         HGOTO_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "Can't mount file onto object from different VOL plugin")
 
-    /* Set wrapper info in API context */
-    if(H5VL_set_vol_wrapper(loc_vol_obj->data, loc_vol_obj->plugin) < 0)
-        HGOTO_ERROR(H5E_OHDR, H5E_CANTSET, H5I_INVALID_HID, "can't set VOL wrapper info")
-    vol_wrapper_set = TRUE;
-
     /* Perform the mount operation */
-    if(H5VL_file_specific(loc_vol_obj->data, loc_vol_obj->plugin->cls, H5VL_FILE_MOUNT, H5P_DATASET_XFER_DEFAULT, 
-                          H5_REQUEST_NULL, loc_type, name, child_vol_obj->data, plist_id) < 0)
+    if(H5VL_file_specific(loc_vol_obj, H5VL_FILE_MOUNT, H5P_DATASET_XFER_DEFAULT, H5_REQUEST_NULL, loc_type, name, child_vol_obj->data, plist_id) < 0)
         HGOTO_ERROR(H5E_FILE, H5E_MOUNT, FAIL, "unable to mount file")
 
 done:
-    /* Reset object wrapping info in API context */
-    if(vol_wrapper_set && H5VL_reset_vol_wrapper() < 0)
-        HDONE_ERROR(H5E_OHDR, H5E_CANTSET, H5I_INVALID_HID, "can't reset VOL wrapper info")
-
     FUNC_LEAVE_API(ret_value)
 } /* end H5Fmount() */
 
@@ -522,7 +511,6 @@ H5Funmount(hid_t loc_id, const char *name)
 {
     H5VL_object_t  *vol_obj = NULL;             /* Parent object        */
     H5I_type_t      loc_type;                   /* ID type of location  */
-    hbool_t         vol_wrapper_set = FALSE;        /* Whether the VOL object wrapping context was set up */
     herr_t          ret_value = SUCCEED;        /* Return value         */
 
     FUNC_ENTER_API(FAIL)
@@ -545,21 +533,11 @@ H5Funmount(hid_t loc_id, const char *name)
     if(NULL == (vol_obj = (H5VL_object_t *)H5I_object(loc_id)))
         HGOTO_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "could not get location object")
 
-    /* Set wrapper info in API context */
-    if(H5VL_set_vol_wrapper(vol_obj->data, vol_obj->plugin) < 0)
-        HGOTO_ERROR(H5E_OHDR, H5E_CANTSET, H5I_INVALID_HID, "can't set VOL wrapper info")
-    vol_wrapper_set = TRUE;
-
     /* Perform the unmount operation */
-    if(H5VL_file_specific(vol_obj->data, vol_obj->plugin->cls, H5VL_FILE_UNMOUNT, 
-                          H5P_DATASET_XFER_DEFAULT, H5_REQUEST_NULL, loc_type, name) < 0)
+    if(H5VL_file_specific(vol_obj, H5VL_FILE_UNMOUNT, H5P_DATASET_XFER_DEFAULT, H5_REQUEST_NULL, loc_type, name) < 0)
         HGOTO_ERROR(H5E_FILE, H5E_MOUNT, FAIL, "unable to unmount file")
 
 done:
-    /* Reset object wrapping info in API context */
-    if(vol_wrapper_set && H5VL_reset_vol_wrapper() < 0)
-        HDONE_ERROR(H5E_OHDR, H5E_CANTSET, H5I_INVALID_HID, "can't reset VOL wrapper info")
-
     FUNC_LEAVE_API(ret_value)
 } /* end H5Funmount() */
 
diff --git a/src/H5VLcallback.c b/src/H5VLcallback.c
index a543379..6d28f83 100644
--- a/src/H5VLcallback.c
+++ b/src/H5VLcallback.c
@@ -95,6 +95,14 @@ static herr_t H5VL__dataset_optional(void *obj, const H5VL_class_t *cls,
     hid_t dxpl_id, void **req, va_list arguments);
 static herr_t H5VL__dataset_close(void *obj, const H5VL_class_t *cls, hid_t dxpl_id,
     void **req);
+static herr_t H5VL__file_get(void *obj, const H5VL_class_t *cls, H5VL_file_get_t get_type, 
+    hid_t dxpl_id, void **req, va_list arguments);
+static herr_t H5VL__file_specific(void *obj, const H5VL_class_t *cls, H5VL_file_specific_t specific_type, 
+    hid_t dxpl_id, void **req, va_list arguments);
+static herr_t H5VL__file_optional(void *obj, const H5VL_class_t *cls, hid_t dxpl_id,
+    void **req, va_list arguments);
+static herr_t H5VL__file_close(void *obj, const H5VL_class_t *cls, hid_t dxpl_id,
+    void **req);
 
 
 /*********************/
@@ -1195,7 +1203,7 @@ H5VLattr_get(void *obj, hid_t plugin_id, H5VL_attr_get_t get_type, hid_t dxpl_id
 
     /* Call the corresponding internal VOL routine */
     if(H5VL__attr_get(obj, cls, get_type, dxpl_id, req, arguments) < 0)
-        HGOTO_ERROR(H5E_VOL, H5E_CANTGET, FAIL, "Unable to get attribute information")
+        HGOTO_ERROR(H5E_VOL, H5E_CANTGET, FAIL, "unable to get attribute information")
 
 done:
     FUNC_LEAVE_API_NOINIT(ret_value)
@@ -1227,7 +1235,7 @@ H5VL__attr_specific(void *obj, H5VL_loc_params_t loc_params, const H5VL_class_t
 
     /* Call the corresponding VOL callback */
     if((ret_value = (cls->attr_cls.specific)(obj, loc_params, specific_type, dxpl_id, req, arguments)) < 0)
-        HGOTO_ERROR(H5E_VOL, H5E_CANTOPERATE, FAIL, "Unable to execute attribute specific callback")
+        HGOTO_ERROR(H5E_VOL, H5E_CANTOPERATE, FAIL, "unable to execute attribute specific callback")
 
 done:
     FUNC_LEAVE_NOAPI(ret_value)
@@ -1264,7 +1272,7 @@ H5VL_attr_specific(const H5VL_object_t *vol_obj, H5VL_loc_params_t loc_params,
     va_start(arguments, req);
     arg_started = TRUE;
     if((ret_value = H5VL__attr_specific(vol_obj->data, loc_params, vol_obj->plugin->cls, specific_type, dxpl_id, req, arguments)) < 0)
-        HGOTO_ERROR(H5E_VOL, H5E_CANTOPERATE, FAIL, "Unable to execute attribute specific callback")
+        HGOTO_ERROR(H5E_VOL, H5E_CANTOPERATE, FAIL, "unable to execute attribute specific callback")
 
 done:
     /* End access to the va_list, if we started it */
@@ -1308,7 +1316,7 @@ H5VLattr_specific(void *obj, H5VL_loc_params_t loc_params, hid_t plugin_id,
 
     /* Call the corresponding internal VOL routine */
     if((ret_value = H5VL__attr_specific(obj, loc_params, cls, specific_type, dxpl_id, req, arguments)) < 0)
-        HGOTO_ERROR(H5E_VOL, H5E_CANTOPERATE, FAIL, "Unable to execute attribute specific callback")
+        HGOTO_ERROR(H5E_VOL, H5E_CANTOPERATE, FAIL, "unable to execute attribute specific callback")
 
 done:
     FUNC_LEAVE_API_NOINIT(ret_value)
@@ -1339,7 +1347,7 @@ H5VL__attr_optional(void *obj, const H5VL_class_t *cls, hid_t dxpl_id,
 
     /* Call the corresponding VOL callback */
     if((cls->attr_cls.optional)(obj, dxpl_id, req, arguments) < 0)
-        HGOTO_ERROR(H5E_VOL, H5E_CANTOPERATE, FAIL, "Unable to execute attribute optional callback")
+        HGOTO_ERROR(H5E_VOL, H5E_CANTOPERATE, FAIL, "unable to execute attribute optional callback")
 
 done:
     FUNC_LEAVE_NOAPI(ret_value)
@@ -1375,7 +1383,7 @@ H5VL_attr_optional(const H5VL_object_t *vol_obj, hid_t dxpl_id, void **req, ...)
     va_start(arguments, req);
     arg_started = TRUE;
     if(H5VL__attr_optional(vol_obj->data, vol_obj->plugin->cls, dxpl_id, req, arguments) < 0)
-        HGOTO_ERROR(H5E_VOL, H5E_CANTOPERATE, FAIL, "Unable to execute attribute optional callback")
+        HGOTO_ERROR(H5E_VOL, H5E_CANTOPERATE, FAIL, "unable to execute attribute optional callback")
 
 done:
     /* End access to the va_list, if we started it */
@@ -1417,7 +1425,7 @@ H5VLattr_optional(void *obj, hid_t plugin_id, hid_t dxpl_id, void **req, va_list
 
     /* Call the corresponding internal VOL routine */
     if(H5VL__attr_optional(obj, cls, dxpl_id, req, arguments) < 0)
-        HGOTO_ERROR(H5E_VOL, H5E_CANTOPERATE, FAIL, "Unable to execute attribute optional callback")
+        HGOTO_ERROR(H5E_VOL, H5E_CANTOPERATE, FAIL, "unable to execute attribute optional callback")
 
 done:
     FUNC_LEAVE_API_NOINIT(ret_value)
@@ -2041,7 +2049,7 @@ H5VLdataset_get(void *obj, hid_t plugin_id, H5VL_dataset_get_t get_type,
 
     /* Call the corresponding internal VOL routine */
     if(H5VL__dataset_get(obj, cls, get_type, dxpl_id, req, arguments) < 0)
-        HGOTO_ERROR(H5E_VOL, H5E_CANTGET, FAIL, "Unable to execute dataset get callback")
+        HGOTO_ERROR(H5E_VOL, H5E_CANTGET, FAIL, "unable to execute dataset get callback")
 
 done:
     FUNC_LEAVE_API_NOINIT(ret_value)
@@ -2214,7 +2222,7 @@ H5VL_dataset_optional(const H5VL_object_t *vol_obj, hid_t dxpl_id,
 
     /* Call the corresponding VOL callback */
     /* Set wrapper info in API context */
-    if(H5VL_set_vol_wrapper(vol_obj->data, vol_obj->plugin) < 1)
+    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;
 
@@ -2387,6 +2395,9 @@ done:
  *
  * Purpose:	Creates a file through the VOL
  *
+ * Note:	Does not have a 'static' version of the routine, since there's
+ *		no objects in the container before this operation completes.
+ *
  * Return:      Success: Pointer to new file
  *		Failure: NULL
  *
@@ -2459,6 +2470,9 @@ done:
  *
  * Purpose:	Opens a file through the VOL.
  *
+ * Note:	Does not have a 'static' version of the routine, since there's
+ *		no objects in the container before this operation completes.
+ *
  * Return:      Success: Pointer to file. 
  *		Failure: NULL
  *
@@ -2527,6 +2541,37 @@ done:
 
 
 /*-------------------------------------------------------------------------
+ * Function:	H5VL__file_get
+ *
+ * Purpose:	Get specific information about the file through the VOL
+ *
+ * Return:      Success:    Non-negative
+ *              Failure:    Negative
+ *
+ *-------------------------------------------------------------------------
+ */
+static herr_t
+H5VL__file_get(void *obj, const H5VL_class_t *cls, H5VL_file_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->file_cls.get)
+        HGOTO_ERROR(H5E_VOL, H5E_UNSUPPORTED, FAIL, "VOL plugin has no 'file get' method")
+
+    /* Call the corresponding VOL callback */
+    if((cls->file_cls.get)(obj, get_type, dxpl_id, req, arguments) < 0)
+        HGOTO_ERROR(H5E_VOL, H5E_CANTGET, FAIL, "file get failed")
+
+done:
+    FUNC_LEAVE_NOAPI(ret_value)
+} /* end H5VL__file_get() */
+
+
+/*-------------------------------------------------------------------------
  * Function:	H5VL_file_get
  *
  * Purpose:	Get specific information about the file through the VOL
@@ -2537,30 +2582,36 @@ done:
  *-------------------------------------------------------------------------
  */
 herr_t
-H5VL_file_get(void *file, const H5VL_class_t *cls, H5VL_file_get_t get_type, 
+H5VL_file_get(const H5VL_object_t *vol_obj, H5VL_file_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->file_cls.get)
-        HGOTO_ERROR(H5E_VOL, H5E_UNSUPPORTED, FAIL, "VOL plugin has no 'file 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->file_cls.get)(file, get_type, dxpl_id, req, arguments) < 0)
-        HGOTO_ERROR(H5E_VOL, H5E_CANTGET, FAIL, "get failed")
+    if(H5VL__file_get(vol_obj->data, vol_obj->plugin->cls, get_type, dxpl_id, req, arguments) < 0)
+        HGOTO_ERROR(H5E_VOL, H5E_CANTGET, FAIL, "file get failed")
 
 done:
     /* End access to the va_list, if we started it */
     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_file_get() */
 
@@ -2576,28 +2627,24 @@ done:
  *-------------------------------------------------------------------------
  */
 herr_t
-H5VLfile_get(void *file, hid_t plugin_id, H5VL_file_get_t get_type,
+H5VLfile_get(void *obj, hid_t plugin_id, H5VL_file_get_t get_type,
     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 */
 
     FUNC_ENTER_API_NOINIT
-    H5TRACE6("e", "*xiVgi**xx", file, plugin_id, get_type, dxpl_id, req, arguments);
+    H5TRACE6("e", "*xiVgi**xx", obj, plugin_id, get_type, dxpl_id, req, arguments);
 
     /* Check args and get class pointer */
-    if(NULL == file)
+    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")
 
-    /* Check if the corresponding VOL callback exists */
-    if(NULL == cls->file_cls.get)
-        HGOTO_ERROR(H5E_VOL, H5E_UNSUPPORTED, FAIL, "VOL plugin has no `file get' method")
-
-    /* Bypass the H5VLint layer, calling the VOL callback directly */
-    if((cls->file_cls.get)(file, get_type, dxpl_id, req, arguments) < 0)
-        HGOTO_ERROR(H5E_VOL, H5E_CANTGET, FAIL, "Unable to execute file get callback")
+    /* Call the corresponding internal VOL routine */
+    if(H5VL__file_get(obj, cls, get_type, dxpl_id, req, arguments) < 0)
+        HGOTO_ERROR(H5E_VOL, H5E_CANTGET, FAIL, "unable to execute file get callback")
 
 done:
     FUNC_LEAVE_API_NOINIT(ret_value)
@@ -2605,9 +2652,40 @@ done:
 
 
 /*-------------------------------------------------------------------------
+ * Function:	H5VL__file_specific
+ *
+ * Purpose:	Perform File specific operations through the VOL
+ *
+ * Return:      Success:    Non-negative
+ *              Failure:    Negative
+ *
+ *-------------------------------------------------------------------------
+ */
+static herr_t
+H5VL__file_specific(void *obj, const H5VL_class_t *cls, H5VL_file_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->file_cls.specific)
+        HGOTO_ERROR(H5E_VOL, H5E_UNSUPPORTED, FAIL, "VOL plugin has no 'file specific' method")
+
+    /* Call the corresponding VOL callback */
+    if((cls->file_cls.specific)(obj, specific_type, dxpl_id, req, arguments) < 0)
+        HGOTO_ERROR(H5E_VOL, H5E_CANTOPERATE, FAIL, "file specific failed")
+
+done:
+    FUNC_LEAVE_NOAPI(ret_value)
+} /* end H5VL__file_specific() */
+
+
+/*-------------------------------------------------------------------------
  * Function:	H5VL_file_specific
  *
- * Purpose:	perform File specific operations through the VOL
+ * Purpose:	Perform File specific operations through the VOL
  *
  * Return:      Success:    Non-negative
  *              Failure:    Negative
@@ -2615,28 +2693,34 @@ done:
  *-------------------------------------------------------------------------
  */
 herr_t
-H5VL_file_specific(void *file, const H5VL_class_t *cls, H5VL_file_specific_t specific_type, 
+H5VL_file_specific(const H5VL_object_t *vol_obj, H5VL_file_specific_t specific_type, 
     hid_t dxpl_id, void **req, ...)
 {
+    const H5VL_class_t *cls;            /* VOL plugin's class struct */
     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)
 
+    /* Start access to the varargs, so they are available in all situations below */
+    va_start(arguments, req);
+    arg_started = TRUE;
+
     /* Special treatment of file access check */
     if(specific_type == H5VL_FILE_IS_ACCESSIBLE) {
         H5P_genplist_t     *plist;          /* Property list pointer */
         H5VL_plugin_prop_t  plugin_prop;    /* Property for VOL plugin ID & info */
         va_list             tmp_args;       /* argument list passed from the API call */
-        hid_t               fapl_id;
+        hid_t               fapl_id;        /* File access property list for accessing the file */
 
-        /* Get the file access property list */
-        va_start(tmp_args, req);
+        /* Get the file access property list to access the file */
+        va_copy(tmp_args, arguments);
         fapl_id = va_arg(tmp_args, hid_t);
         va_end(tmp_args);
 
-        /* Get the VOL info from the fapl */
+        /* Get the VOL info from the FAPL */
         if(NULL == (plist = (H5P_genplist_t *)H5I_object(fapl_id)))
             HGOTO_ERROR(H5E_VOL, H5E_BADTYPE, FAIL, "not a file access property list")
         if(H5P_peek(plist, H5F_ACS_VOL_DRV_NAME, &plugin_prop) < 0)
@@ -2645,30 +2729,34 @@ H5VL_file_specific(void *file, const H5VL_class_t *cls, H5VL_file_specific_t spe
         /* Get class pointer */
         if(NULL == (cls = (H5VL_class_t *)H5I_object_verify(plugin_prop.plugin_id, H5I_VOL)))
             HGOTO_ERROR(H5E_VOL, H5E_BADTYPE, FAIL, "not a VOL plugin ID")
-
-        /* Call the corresponding VOL callback */
-        va_start(arguments, req);
-        arg_started = TRUE;
-        if((cls->file_cls.specific)(file, specific_type, dxpl_id, req, arguments) < 0)
-            HGOTO_ERROR(H5E_VOL, H5E_CANTOPERATE, FAIL, "file specific failed")
     } /* end if */
+    /* Set wrapper info in API context, for all other operations */
     else {
-        /* Check if the corresponding VOL callback exists */
-        if(NULL == cls->file_cls.specific)
-            HGOTO_ERROR(H5E_VOL, H5E_UNSUPPORTED, FAIL, "VOL plugin has no 'file specific' method")
-
-        /* Call the corresponding VOL callback */
-        va_start(arguments, req);
-        arg_started = TRUE;
-        if((cls->file_cls.specific)(file, specific_type, dxpl_id, req, arguments) < 0)
-            HGOTO_ERROR(H5E_VOL, H5E_CANTOPERATE, FAIL, "file specific failed")
+        /* Sanity check */
+        HDassert(vol_obj);
+
+        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;
+
+        /* Set the VOL plugin class pointer */
+        cls = vol_obj->plugin->cls;
     } /* end else */
 
+
+    /* Call the corresponding internal VOL routine */
+    if(H5VL__file_specific(vol_obj ? vol_obj->data : NULL, cls, specific_type, dxpl_id, req, arguments) < 0)
+        HGOTO_ERROR(H5E_VOL, H5E_CANTOPERATE, FAIL, "file specific failed")
+
 done:
     /* End access to the va_list, if we started it */
     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_file_specific() */
 
@@ -2678,69 +2766,72 @@ done:
  *
  * Purpose:     Performs a plugin-specific operation on a file
  *
+ * Note:	The 'obj' parameter is allowed to be NULL
+ *
  * Return:      Success:    Non-negative
  *              Failure:    Negative
  *
  *-------------------------------------------------------------------------
  */
 herr_t
-H5VLfile_specific(void *file, hid_t plugin_id, H5VL_file_specific_t specific_type,
+H5VLfile_specific(void *obj, hid_t plugin_id, H5VL_file_specific_t specific_type,
     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 */
 
     FUNC_ENTER_API_NOINIT
-    H5TRACE6("e", "*xiVhi**xx", file, plugin_id, specific_type, dxpl_id, req,
+    H5TRACE6("e", "*xiVhi**xx", obj, plugin_id, specific_type, dxpl_id, req,
              arguments);
 
-    /* Special treatment of file access check */
-    if(specific_type == H5VL_FILE_IS_ACCESSIBLE) {
-        H5P_genplist_t     *plist;          /* Property list pointer */
-        H5VL_plugin_prop_t  plugin_prop;            /* Property for VOL plugin ID & info */
-        hid_t               fapl_id;
+    /* Check args and get class pointer */
+    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")
 
-        fapl_id = va_arg(arguments, hid_t);
+    /* Call the corresponding internal VOL routine */
+    if(H5VL__file_specific(obj, cls, specific_type, dxpl_id, req, arguments) < 0)
+        HGOTO_ERROR(H5E_VOL, H5E_CANTOPERATE, FAIL, "unable to execute file specific callback")
 
-        /* Get the VOL info from the fapl */
-        if(NULL == (plist = (H5P_genplist_t *)H5I_object(fapl_id)))
-            HGOTO_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "not a file access property list")
-        if(H5P_peek(plist, H5F_ACS_VOL_DRV_NAME, &plugin_prop) < 0)
-            HGOTO_ERROR(H5E_PLIST, H5E_CANTGET, FAIL, "can't get VOL plugin info")
+done:
+    FUNC_LEAVE_API_NOINIT(ret_value)
+} /* end H5VLfile_specific() */
 
-        /* Get class pointer */
-        if(NULL == (cls = (H5VL_class_t *)H5I_object_verify(plugin_prop.plugin_id, H5I_VOL)))
-            HGOTO_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "not a VOL plugin ID")
+
+/*-------------------------------------------------------------------------
+ * Function:	H5VL__file_optional
+ *
+ * Purpose:	Perform a plugin specific operation
+ *
+ * Return:      Success:    Non-negative
+ *              Failure:    Negative
+ *
+ *-------------------------------------------------------------------------
+ */
+static herr_t
+H5VL__file_optional(void *obj, const H5VL_class_t *cls, hid_t dxpl_id,
+    void **req, va_list arguments)
+{
+    herr_t ret_value = SUCCEED;         /* Return value */
 
-        /* Bypass the H5VLint layer, calling the VOL callback directly */
-        if((cls->file_cls.specific)(file, specific_type, dxpl_id, req, arguments) < 0)
-            HGOTO_ERROR(H5E_VOL, H5E_CANTOPERATE, FAIL, "file specific failed")
-    } /* end if */
-    else {
-        /* Check args and get class pointer */
-        if(NULL == file)
-            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")
-
-        /* Check if the corresponding VOL callback exists */
-        if(NULL == cls->file_cls.specific)
-            HGOTO_ERROR(H5E_VOL, H5E_UNSUPPORTED, FAIL, "VOL plugin has no `file specific' method")
-
-        /* Bypass the H5VLint layer, calling the VOL callback directly */
-        if((cls->file_cls.specific)(file, specific_type, dxpl_id, req, arguments) < 0)
-            HGOTO_ERROR(H5E_VOL, H5E_CANTOPERATE, FAIL, "Unable to execute file specific callback")
-    } /* end else */
+    FUNC_ENTER_STATIC
+
+    /* Check if the corresponding VOL callback exists */
+    if(NULL == cls->file_cls.optional)
+        HGOTO_ERROR(H5E_VOL, H5E_UNSUPPORTED, FAIL, "VOL plugin has no 'file optional' method")
+
+    /* Call the corresponding VOL callback */
+    if((cls->file_cls.optional)(obj, dxpl_id, req, arguments) < 0)
+        HGOTO_ERROR(H5E_VOL, H5E_CANTOPERATE, FAIL, "file optional failed")
 
 done:
-    FUNC_LEAVE_API_NOINIT(ret_value)
-} /* end H5VLfile_specific() */
+    FUNC_LEAVE_NOAPI(ret_value)
+} /* end H5VL__file_optional() */
 
 
 /*-------------------------------------------------------------------------
  * Function:	H5VL_file_optional
  *
- * Purpose:	perform a plugin specific operation
+ * Purpose:	Perform a plugin specific operation
  *
  * Return:      Success:    Non-negative
  *              Failure:    Negative
@@ -2748,23 +2839,24 @@ done:
  *-------------------------------------------------------------------------
  */
 herr_t
-H5VL_file_optional(void *file, const H5VL_class_t *cls, hid_t dxpl_id,
-    void **req, ...)
+H5VL_file_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->file_cls.optional)
-        HGOTO_ERROR(H5E_VOL, H5E_UNSUPPORTED, FAIL, "VOL plugin has no 'file 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->file_cls.optional)(file, dxpl_id, req, arguments) < 0)
+    if(H5VL__file_optional(vol_obj->data, vol_obj->plugin->cls, dxpl_id, req, arguments) < 0)
         HGOTO_ERROR(H5E_VOL, H5E_CANTOPERATE, FAIL, "file optional failed")
 
 done:
@@ -2772,6 +2864,10 @@ 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_file_optional() */
 
@@ -2787,28 +2883,24 @@ done:
  *-------------------------------------------------------------------------
  */
 herr_t
-H5VLfile_optional(void *file, hid_t plugin_id, hid_t dxpl_id, void **req,
+H5VLfile_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 */
 
     FUNC_ENTER_API_NOINIT
-    H5TRACE5("e", "*xii**xx", file, plugin_id, dxpl_id, req, arguments);
+    H5TRACE5("e", "*xii**xx", obj, plugin_id, dxpl_id, req, arguments);
 
     /* Check args and get class pointer */
-    if(NULL == file)
+    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")
 
-    /* Check if the corresponding VOL callback exists */
-    if(NULL == cls->file_cls.optional)
-        HGOTO_ERROR(H5E_VOL, H5E_UNSUPPORTED, FAIL, "VOL plugin has no `file optional' method")
-
-    /* Bypass the H5VLint layer, calling the VOL callback directly */
-    if((cls->file_cls.optional)(file, dxpl_id, req, arguments) < 0)
-        HGOTO_ERROR(H5E_VOL, H5E_CANTOPERATE, FAIL, "Unable to execute file optional callback")
+    /* Call the corresponding internal VOL routine */
+    if(H5VL__file_optional(obj, cls, dxpl_id, req, arguments) < 0)
+        HGOTO_ERROR(H5E_VOL, H5E_CANTOPERATE, FAIL, "unable to execute file optional callback")
 
 done:
     FUNC_LEAVE_API_NOINIT(ret_value)
@@ -2816,7 +2908,7 @@ done:
 
 
 /*-------------------------------------------------------------------------
- * Function:    H5VL_file_close
+ * Function:    H5VL__file_close
  *
  * Purpose:     Closes a file through the VOL
  *
@@ -2825,14 +2917,15 @@ done:
  *
  *-------------------------------------------------------------------------
  */
-herr_t
-H5VL_file_close(void *file, const H5VL_class_t *cls, hid_t dxpl_id, void **req)
+static herr_t
+H5VL__file_close(void *obj, const H5VL_class_t *cls, hid_t dxpl_id, void **req)
 {
     herr_t ret_value = SUCCEED;         /* Return value */
 
-    FUNC_ENTER_NOAPI(FAIL)
+    FUNC_ENTER_STATIC
 
-    HDassert(file);
+    /* Sanity check */
+    HDassert(obj);
     HDassert(cls);
 
     /* Check if the corresponding VOL callback exists */
@@ -2840,11 +2933,47 @@ H5VL_file_close(void *file, const H5VL_class_t *cls, hid_t dxpl_id, void **req)
         HGOTO_ERROR(H5E_VOL, H5E_UNSUPPORTED, FAIL, "VOL plugin has no 'file close' method")
 
     /* Call the corresponding VOL callback */
-    if((cls->file_cls.close)(file, dxpl_id, req) < 0)
-        HGOTO_ERROR(H5E_VOL, H5E_CANTCLOSEFILE, FAIL, "close failed")
+    if((cls->file_cls.close)(obj, dxpl_id, req) < 0)
+        HGOTO_ERROR(H5E_VOL, H5E_CANTCLOSEFILE, FAIL, "file close failed")
 
 done:
     FUNC_LEAVE_NOAPI(ret_value)
+} /* end H5VL__file_close() */
+
+
+/*-------------------------------------------------------------------------
+ * Function:    H5VL_file_close
+ *
+ * Purpose:     Closes a file through the VOL
+ *
+ * Return:      Success:    Non-negative
+ *              Failure:    Negative
+ *
+ *-------------------------------------------------------------------------
+ */
+herr_t
+H5VL_file_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__file_close(vol_obj->data, vol_obj->plugin->cls, dxpl_id, req) < 0)
+        HGOTO_ERROR(H5E_VOL, H5E_CANTCLOSEFILE, FAIL, "file 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_file_close() */
 
 
@@ -2859,22 +2988,22 @@ done:
  *-------------------------------------------------------------------------
  */
 herr_t
-H5VLfile_close(void *file, hid_t plugin_id, hid_t dxpl_id, void **req)
+H5VLfile_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", file, plugin_id, dxpl_id, req);
+    H5TRACE4("e", "*xii**x", obj, plugin_id, dxpl_id, req);
 
     /* Check args and get class pointer */
-    if(NULL == file)
+    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_file_close(file, cls, dxpl_id, req) < 0)
+    if(H5VL__file_close(obj, cls, dxpl_id, req) < 0)
         HGOTO_ERROR(H5E_VOL, H5E_CANTCLOSEFILE, FAIL, "unable to close file")
 
 done:
@@ -3087,7 +3216,7 @@ H5VLgroup_get(void *obj, hid_t plugin_id, H5VL_group_get_t get_type,
 
     /* Bypass the H5VLint layer, calling the VOL callback directly */
     if((cls->group_cls.get)(obj, get_type, dxpl_id, req, arguments) < 0)
-        HGOTO_ERROR(H5E_VOL, H5E_CANTGET, FAIL, "Unable to execute group get callback")
+        HGOTO_ERROR(H5E_VOL, H5E_CANTGET, FAIL, "unable to execute group get callback")
 
 done:
     FUNC_LEAVE_API_NOINIT(ret_value)
@@ -3122,7 +3251,7 @@ H5VL_group_specific(void *obj, const H5VL_class_t *cls, H5VL_group_specific_t sp
     va_start(arguments, req);
     arg_started = TRUE;
     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")
+        HGOTO_ERROR(H5E_VOL, H5E_CANTOPERATE, FAIL, "unable to execute group specific callback")
 
 done:
     /* End access to the va_list, if we started it */
@@ -3166,7 +3295,7 @@ H5VLgroup_specific(void *obj, hid_t plugin_id, H5VL_group_specific_t specific_ty
 
     /* Bypass the H5VLint layer, calling the VOL callback directly */
     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")
+        HGOTO_ERROR(H5E_VOL, H5E_CANTOPERATE, FAIL, "unable to execute group specific callback")
 
 done:
     FUNC_LEAVE_API_NOINIT(ret_value)
@@ -3201,7 +3330,7 @@ H5VL_group_optional(void *obj, const H5VL_class_t *cls, hid_t dxpl_id,
     va_start(arguments, req);
     arg_started = TRUE;
     if((cls->group_cls.optional)(obj, dxpl_id, req, arguments) < 0)
-        HGOTO_ERROR(H5E_VOL, H5E_CANTOPERATE, FAIL, "Unable to execute group optional callback")
+        HGOTO_ERROR(H5E_VOL, H5E_CANTOPERATE, FAIL, "unable to execute group optional callback")
 
 done:
     /* End access to the va_list, if we started it */
@@ -3243,7 +3372,7 @@ H5VLgroup_optional(void *obj, hid_t plugin_id, hid_t dxpl_id, void **req, va_lis
 
     /* Bypass the H5VLint layer, calling the VOL callback directly */
     if((cls->group_cls.optional)(obj, dxpl_id, req, arguments) < 0)
-        HGOTO_ERROR(H5E_VOL, H5E_CANTOPERATE, FAIL, "Unable to execute group optional callback")
+        HGOTO_ERROR(H5E_VOL, H5E_CANTOPERATE, FAIL, "unable to execute group optional callback")
 
 done:
     FUNC_LEAVE_API_NOINIT(ret_value)
@@ -3595,7 +3724,7 @@ H5VLlink_get(void *obj, H5VL_loc_params_t loc_params, hid_t plugin_id, H5VL_link
 
     /* Bypass the H5VLint layer, calling the VOL callback directly */
     if((cls->link_cls.get)(obj, loc_params, get_type, dxpl_id, req, arguments) < 0)
-        HGOTO_ERROR(H5E_VOL, H5E_CANTGET, FAIL, "Unable to execute link get callback")
+        HGOTO_ERROR(H5E_VOL, H5E_CANTGET, FAIL, "unable to execute link get callback")
 
 done:
     FUNC_LEAVE_API_NOINIT(ret_value)
@@ -3630,7 +3759,7 @@ H5VL_link_specific(void *obj, H5VL_loc_params_t loc_params, const H5VL_class_t *
     va_start(arguments, req);
     arg_started = TRUE;
     if((ret_value = (cls->link_cls.specific)(obj, loc_params, specific_type, dxpl_id, req, arguments)) < 0)
-        HGOTO_ERROR(H5E_VOL, H5E_CANTOPERATE, FAIL, "Unable to execute link specific callback")
+        HGOTO_ERROR(H5E_VOL, H5E_CANTOPERATE, FAIL, "unable to execute link specific callback")
 
 done:
     /* End access to the va_list, if we started it */
@@ -3674,7 +3803,7 @@ H5VLlink_specific(void *obj, H5VL_loc_params_t loc_params, hid_t plugin_id,
 
     /* Bypass the H5VLint layer, calling the VOL callback directly */
     if((ret_value = (cls->link_cls.specific)(obj, loc_params, specific_type, dxpl_id, req, arguments)) < 0)
-        HGOTO_ERROR(H5E_VOL, H5E_CANTOPERATE, FAIL, "Unable to execute link specific callback")
+        HGOTO_ERROR(H5E_VOL, H5E_CANTOPERATE, FAIL, "unable to execute link specific callback")
 
 done:
     FUNC_LEAVE_API_NOINIT(ret_value)
@@ -3709,7 +3838,7 @@ H5VL_link_optional(void *obj, const H5VL_class_t *cls, hid_t dxpl_id,
     va_start(arguments, req);
     arg_started = TRUE;
     if((cls->link_cls.optional)(obj, dxpl_id, req, arguments) < 0)
-        HGOTO_ERROR(H5E_VOL, H5E_CANTOPERATE, FAIL, "Unable to execute link optional callback")
+        HGOTO_ERROR(H5E_VOL, H5E_CANTOPERATE, FAIL, "unable to execute link optional callback")
 
 done:
     /* End access to the va_list, if we started it */
@@ -3751,7 +3880,7 @@ H5VLlink_optional(void *obj, hid_t plugin_id, hid_t dxpl_id, void **req, va_list
 
     /* Bypass the H5VLint layer, calling the VOL callback directly */
     if((cls->link_cls.optional)(obj, dxpl_id, req, arguments) < 0)
-        HGOTO_ERROR(H5E_VOL, H5E_CANTOPERATE, FAIL, "Unable to execute link optional callback")
+        HGOTO_ERROR(H5E_VOL, H5E_CANTOPERATE, FAIL, "unable to execute link optional callback")
 
 done:
     FUNC_LEAVE_API_NOINIT(ret_value)
@@ -3975,7 +4104,7 @@ H5VLobject_get(void *obj, H5VL_loc_params_t loc_params, hid_t plugin_id, H5VL_ob
 
     /* Bypass the H5VLint layer, calling the VOL callback directly */
     if((cls->object_cls.get)(obj, loc_params, get_type, dxpl_id, req, arguments) < 0)
-        HGOTO_ERROR(H5E_VOL, H5E_CANTGET, FAIL, "Unable to execute object get callback")
+        HGOTO_ERROR(H5E_VOL, H5E_CANTGET, FAIL, "unable to execute object get callback")
 
 done:
     FUNC_LEAVE_API_NOINIT(ret_value)
@@ -4054,7 +4183,7 @@ H5VLobject_specific(void *obj, H5VL_loc_params_t loc_params, hid_t plugin_id,
 
     /* Bypass the H5VLint layer, calling the VOL callback directly */
     if((ret_value = (cls->object_cls.specific)(obj, loc_params, specific_type, dxpl_id, req, arguments)) < 0)
-        HGOTO_ERROR(H5E_VOL, H5E_CANTOPERATE, FAIL, "Unable to execute object specific callback")
+        HGOTO_ERROR(H5E_VOL, H5E_CANTOPERATE, FAIL, "unable to execute object specific callback")
 
 done:
     FUNC_LEAVE_API_NOINIT(ret_value)
@@ -4089,7 +4218,7 @@ H5VL_object_optional(void *obj, const H5VL_class_t *cls, hid_t dxpl_id,
     va_start(arguments, req);
     arg_started = TRUE;
     if((cls->object_cls.optional)(obj, dxpl_id, req, arguments) < 0)
-        HGOTO_ERROR(H5E_VOL, H5E_CANTOPERATE, FAIL, "Unable to execute object optional callback")
+        HGOTO_ERROR(H5E_VOL, H5E_CANTOPERATE, FAIL, "unable to execute object optional callback")
 
 done:
     /* End access to the va_list, if we started it */
@@ -4131,7 +4260,7 @@ H5VLobject_optional(void *obj, hid_t plugin_id, hid_t dxpl_id, void **req, va_li
 
     /* Bypass the H5VLint layer, calling the VOL callback directly */
     if((cls->object_cls.optional)(obj, dxpl_id, req, arguments) < 0)
-        HGOTO_ERROR(H5E_VOL, H5E_CANTOPERATE, FAIL, "Unable to execute object optional callback")
+        HGOTO_ERROR(H5E_VOL, H5E_CANTOPERATE, FAIL, "unable to execute object optional callback")
 
 done:
     FUNC_LEAVE_API_NOINIT(ret_value)
@@ -4345,7 +4474,7 @@ H5VLdatatype_get(void *obj, hid_t plugin_id, H5VL_datatype_get_t get_type,
 
     /* Bypass the H5VLint layer, calling the VOL callback directly */
     if((cls->datatype_cls.get)(obj, get_type, dxpl_id, req, arguments) < 0)
-        HGOTO_ERROR(H5E_VOL, H5E_CANTGET, FAIL, "Unable to execute datatype get callback")
+        HGOTO_ERROR(H5E_VOL, H5E_CANTGET, FAIL, "unable to execute datatype get callback")
 
 done:
     FUNC_LEAVE_API_NOINIT(ret_value)
@@ -4380,7 +4509,7 @@ H5VL_datatype_specific(void *obj, const H5VL_class_t *cls, H5VL_datatype_specifi
     va_start(arguments, req);
     arg_started = TRUE;
     if((cls->datatype_cls.specific)(obj, specific_type, dxpl_id, req, arguments) < 0)
-        HGOTO_ERROR(H5E_VOL, H5E_CANTOPERATE, FAIL, "Unable to execute datatype specific callback")
+        HGOTO_ERROR(H5E_VOL, H5E_CANTOPERATE, FAIL, "unable to execute datatype specific callback")
 
 done:
     /* End access to the va_list, if we started it */
@@ -4424,7 +4553,7 @@ H5VLdatatype_specific(void *obj, hid_t plugin_id, H5VL_datatype_specific_t speci
 
     /* Bypass the H5VLint layer, calling the VOL callback directly */
     if((cls->datatype_cls.specific)(obj, specific_type, dxpl_id, req, arguments) < 0)
-        HGOTO_ERROR(H5E_VOL, H5E_CANTOPERATE, FAIL, "Unable to execute datatype specific callback")
+        HGOTO_ERROR(H5E_VOL, H5E_CANTOPERATE, FAIL, "unable to execute datatype specific callback")
 
 done:
     FUNC_LEAVE_API_NOINIT(ret_value)
@@ -4459,7 +4588,7 @@ H5VL_datatype_optional(void *obj, const H5VL_class_t *cls, hid_t dxpl_id,
     va_start(arguments, req);
     arg_started = TRUE;
     if((cls->datatype_cls.optional)(obj, dxpl_id, req, arguments) < 0)
-        HGOTO_ERROR(H5E_VOL, H5E_CANTOPERATE, FAIL, "Unable to execute datatype optional callback")
+        HGOTO_ERROR(H5E_VOL, H5E_CANTOPERATE, FAIL, "unable to execute datatype optional callback")
 
 done:
     /* End access to the va_list, if we started it */
@@ -4502,7 +4631,7 @@ H5VLdatatype_optional(void *obj, hid_t plugin_id, hid_t dxpl_id, void **req,
 
     /* Bypass the H5VLint layer, calling the VOL callback directly */
     if((cls->datatype_cls.optional)(obj, dxpl_id, req, arguments) < 0)
-        HGOTO_ERROR(H5E_VOL, H5E_CANTOPERATE, FAIL, "Unable to execute datatype optional callback")
+        HGOTO_ERROR(H5E_VOL, H5E_CANTOPERATE, FAIL, "unable to execute datatype optional callback")
 
 done:
     FUNC_LEAVE_API_NOINIT(ret_value)
diff --git a/src/H5VLprivate.h b/src/H5VLprivate.h
index 51d99b4..1e91523 100644
--- a/src/H5VLprivate.h
+++ b/src/H5VLprivate.h
@@ -125,10 +125,10 @@ H5_DLL herr_t H5VL_dataset_close(const H5VL_object_t *vol_obj, hid_t dxpl_id, vo
 /* File functions */
 H5_DLL void *H5VL_file_create(const H5VL_class_t *cls, const char *name, unsigned flags, hid_t fcpl_id, hid_t fapl_id, hid_t dxpl_id, void **req);
 H5_DLL void *H5VL_file_open(const H5VL_class_t *cls, const char *name, unsigned flags, hid_t fapl_id, hid_t dxpl_id, void **req);
-H5_DLL herr_t H5VL_file_get(void *file, const H5VL_class_t *cls, H5VL_file_get_t get_type, hid_t dxpl_id, void **req, ...);
-H5_DLL herr_t H5VL_file_specific(void *obj, const H5VL_class_t *cls, H5VL_file_specific_t specific_type, hid_t dxpl_id, void **req, ...);
-H5_DLL herr_t H5VL_file_optional(void *obj, const H5VL_class_t *cls, hid_t dxpl_id, void **req, ...);
-H5_DLL herr_t H5VL_file_close(void *file, const H5VL_class_t *cls, hid_t dxpl_id, void **req);
+H5_DLL herr_t H5VL_file_get(const H5VL_object_t *vol_obj, H5VL_file_get_t get_type, hid_t dxpl_id, void **req, ...);
+H5_DLL herr_t H5VL_file_specific(const H5VL_object_t *vol_obj, H5VL_file_specific_t specific_type, hid_t dxpl_id, void **req, ...);
+H5_DLL herr_t H5VL_file_optional(const H5VL_object_t *vol_obj, hid_t dxpl_id, void **req, ...);
+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);