Refactor all the 'H5VL_*_optional' callbacks to move the type of operation out

of the va_list, so it's at least possible for another connector to know what
the operation is and decide whether to implement it or not.

Added a new VOL sub-class called "introspect" where callbacks that report
information about the connector or container can be placed.  Added an
'opt_query' callback to this sub-class, for a connector to report back
to the library whether a particular optional callback operation is supported.
Also added a 'get_conn_cls' introspection callback, to retrieve the H5VL_class_t
of a connector (either the "current" connector, H5VL_GET_CONN_LVL_CURR, or
the terminal connector, H5VL_GET_CONN_LVL_TERM).

Moved the "post open" operation from a file 'specific' operation to a file
'optional' operation, now that it's possible to detect (with the 'opt_query'
introspection callback) whether a VOL connector implements an optional
operation, without just returning an error.

Added new internal VOL helper routines: H5VL_object_is_native, to determine
if an object is in (or is a) native file, and H5VL_file_is_same, to determine
if two objects are in (or are) the same terminal VOL connector's container.
(And moved the special handling for FILE_IS_EQUAL operation out of internal VOL
callback routine into H5VL_file_is_same)

Made new dataset 'get' operation for H5Dvlen_get_buf_size, aligning it better
with other 'get' operations in API.

Fixed several issues with pass-through connectors, which are now passing the
'make check-passthrough-vol' tests again.

A bunch of warning and style cleanups as well.

1 files changed, 5 insertions, 5 deletions

diff --git a/src/H5Fdeprec.c b/src/H5Fdeprec.c
index 18e915f..a047161 100644
--- a/src/H5Fdeprec.c
+++ b/src/H5Fdeprec.c
@@ -120,7 +120,7 @@ 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, H5P_DATASET_XFER_DEFAULT, H5_REQUEST_NULL, H5VL_NATIVE_FILE_GET_INFO, type, &finfo2) < 0)
+    if(H5VL_file_optional(vol_obj, H5VL_NATIVE_FILE_GET_INFO, H5P_DATASET_XFER_DEFAULT, H5_REQUEST_NULL, type, &finfo2) < 0)
         HGOTO_ERROR(H5E_FILE, H5E_CANTGET, FAIL, "unable to retrieve file info")
 
     /* Copy the compatible fields into the older struct */
@@ -177,10 +177,10 @@ done:
  *              bounds.
  *
  *              Before release 1.10.2, the library supports only two
- *              combinations of low/high bounds: 
+ *              combinations of low/high bounds:
  *                  (earliest, latest)
  *                  (latest, latest)
- *              Thus, this public routine does the job in switching 
+ *              Thus, this public routine does the job in switching
  *              between the two combinations listed above.
  *
  *              Starting release 1.10.2, we add v18 to the enumerated
@@ -198,7 +198,7 @@ done:
  * Return:      Non-negative on success/Negative on failure
  *
  * Programmer:  Vailin Choi; December 2017
- *             
+ *
  *-------------------------------------------------------------------------
  */
 herr_t
@@ -227,7 +227,7 @@ 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, H5P_DATASET_XFER_DEFAULT, H5_REQUEST_NULL, H5VL_NATIVE_FILE_SET_LIBVER_BOUNDS, (int)low, (int)high) < 0)
+    if(H5VL_file_optional(vol_obj, H5VL_NATIVE_FILE_SET_LIBVER_BOUNDS, H5P_DATASET_XFER_DEFAULT, H5_REQUEST_NULL, (int)low, (int)high) < 0)
         HGOTO_ERROR(H5E_FILE, H5E_CANTSET, FAIL, "can't set library version bounds")
 
 done: