Much normalization with develop (#701)

* Brings CMake updates from develop

* Brings reduction in pedantic casts from develop

* Purges UFAIL from the library (#637)

* Committing clang-format changes

* Purges UFAIL from the library

* H5HL_insert change requested in PR

Co-authored-by: github-actions <41898282+github-actions[bot]@users.noreply.github.com>

* Removes gratuitous (double)x.yF casts (#632)

* Committing clang-format changes

* Removes gratuitous (double)x.yF casts

* Committing clang-format changes

Co-authored-by: github-actions <41898282+github-actions[bot]@users.noreply.github.com>

* Committing clang-format changes

* Cleans up a const warning left over from previous constification (#633)

* Committing clang-format changes

* Adds consts to a few global variables

* Cleans up a const warning left over from previous constification

Co-authored-by: github-actions <41898282+github-actions[bot]@users.noreply.github.com>

* Formatted source

* Bring over some VOL registration changes

* VOL cleanup

* H5VL_request_status_t substitutions

* H5F.c cleanup

* Minor API tweaks from develop

* Moves H5G package init/teardown to H5Gint.c

* H5G cleanup

* H5M cleanup

* H5SM cleanup

* H5T cleanup

* H5R cleanup

* H5Lpublic.h cleanup

* H5L cleanup

* H5O cleanup

* H5A, H5CS, and H5AC cleanup

* Moved H5A init/teardown code to H5Aint.c

* Moves H5D I/O functions to H5D.c

* H5D cleanup

* Misc minor cleanup

* H5P close cleanup

* H5Tpublic.h cleanup

* Fixes err_compat test

* H5PLpublic.h cleanup

* Updates H5Ppublic.h

* H5Fpublic.h updates

* H5A.c cleanup

* Brings over H5Aexists and related changes

* Brings CMake shell testing changes from develop

* Close callback changes

* H5R and H5Tcommit normalization

* err_compat test works now

* H5O tweaks

* Updates VOL registration code

* Brings over H5VL_create_object

* H5Tconv.c reformatting

* H5T.c tweaks

* Brings datatype and reference updates from develop

* Brings VOL plugin loading changes from develop

* Brings event sets from develop

* Brings async functions over

* Tools changes

* Brings over many tools changes from develop

* Brings VOL flags from develop

* Fixes h5dump double/float tests

* Updates h5repack tests

* Brings h5diff test changes from develop

* Last h5dump changes

* Brings test changes from develop

* Committing clang-format changes

* Tidied h5_testing()

* Brings chunk iteration code + misc from develop

* Updates vds test

* Enables external link parallel test

* Brings updated property lists from develop

* H5G changes from develop

* H5MF cleanup

* Brings vfd_swmr test back into CMake

* Updates threadsafe test

* Updates plist test

* Brings recent changes from develop

Co-authored-by: github-actions <41898282+github-actions[bot]@users.noreply.github.com>

1 files changed, 530 insertions, 328 deletions

diff --git a/src/H5G.c b/src/H5G.c
index 05fc891..0163d65 100644
--- a/src/H5G.c
+++ b/src/H5G.c
@@ -83,6 +83,7 @@
 #include "H5private.h"   /* Generic Functions                        */
 #include "H5CXprivate.h" /* API Contexts                             */
 #include "H5Eprivate.h"  /* Error handling                           */
+#include "H5ESprivate.h" /* Event Sets                               */
 #include "H5Gpkg.h"      /* Groups                                   */
 #include "H5Iprivate.h"  /* IDs                                      */
 #include "H5Pprivate.h"  /* Property lists                           */
@@ -104,16 +105,24 @@
 /* Local Prototypes */
 /********************/
 
-/* Group close callback */
-static herr_t H5G__close_cb(H5VL_object_t *grp_vol_obj);
+/* Helper routines for sync/async API calls */
+static hid_t  H5G__create_api_common(hid_t loc_id, const char *name, hid_t lcpl_id, hid_t gcpl_id,
+                                     hid_t gapl_id, void **token_ptr, H5VL_object_t **_vol_obj_ptr);
+static hid_t  H5G__open_api_common(hid_t loc_id, const char *name, hid_t gapl_id, void **token_ptr,
+                                   H5VL_object_t **_vol_obj_ptr);
+static herr_t H5G__get_info_api_common(hid_t loc_id, H5G_info_t *group_info /*out*/, void **token_ptr,
+                                       H5VL_object_t **_vol_obj_ptr);
+static herr_t H5G__get_info_by_name_api_common(hid_t loc_id, const char *name, H5G_info_t *group_info /*out*/,
+                                               hid_t lapl_id, void **token_ptr, H5VL_object_t **_vol_obj_ptr);
+static herr_t H5G__get_info_by_idx_api_common(hid_t loc_id, const char *group_name, H5_index_t idx_type,
+                                              H5_iter_order_t order, hsize_t n,
+                                              H5G_info_t *group_info /*out*/, hid_t lapl_id, void **token_ptr,
+                                              H5VL_object_t **_vol_obj_ptr);
 
 /*********************/
 /* Package Variables */
 /*********************/
 
-/* Package initialization variable */
-hbool_t H5_PKG_INIT_VAR = FALSE;
-
 /*****************************/
 /* Library Private Variables */
 /*****************************/
@@ -122,181 +131,70 @@ hbool_t H5_PKG_INIT_VAR = FALSE;
 /* Local Variables */
 /*******************/
 
-/* Group ID class */
-static const H5I_class_t H5I_GROUP_CLS[1] = {{
-    H5I_GROUP,                /* ID class value */
-    0,                        /* Class flags */
-    0,                        /* # of reserved IDs for class */
-    (H5I_free_t)H5G__close_cb /* Callback routine for closing objects of this class */
-}};
-
-/* Flag indicating "top" of interface has been initialized */
-static hbool_t H5G_top_package_initialize_s = FALSE;
-
-/*-------------------------------------------------------------------------
- * Function: H5G_init
- *
- * Purpose:  Initialize the interface from some other layer.
- *
- * Return:   Success:    non-negative
- *
- *           Failure:    negative
- *-------------------------------------------------------------------------
- */
-herr_t
-H5G_init(void)
-{
-    herr_t ret_value = SUCCEED; /* Return value */
-
-    FUNC_ENTER_NOAPI(FAIL)
-    /* FUNC_ENTER() does all the work */
-
-done:
-    FUNC_LEAVE_NOAPI(ret_value)
-} /* end H5G_init() */
-
 /*-------------------------------------------------------------------------
- * Function:	H5G__init_package
- *
- * Purpose:	Initializes the H5G interface.
+ * Function:    H5G__create_api_common
  *
- * Return:	Non-negative on success/Negative on failure
+ * Purpose:     This is the common function for creating HDF5 groups.
  *
- * Programmer:	Robb Matzke
- *		Monday, January	 5, 1998
- *
- * Notes:       The group creation properties are registered in the property
- *              list interface initialization routine (H5P_init_package)
- *              so that the file creation property class can inherit from it
- *              correctly. (Which allows the file creation property list to
- *              control the group creation properties of the root group of
- *              a file) QAK - 24/10/2005
- *
- *-------------------------------------------------------------------------
- */
-herr_t
-H5G__init_package(void)
-{
-    herr_t ret_value = SUCCEED; /* Return value */
-
-    FUNC_ENTER_PACKAGE
-
-    /* Initialize the atom group for the group IDs */
-    if (H5I_register_type(H5I_GROUP_CLS) < 0)
-        HGOTO_ERROR(H5E_SYM, H5E_CANTINIT, FAIL, "unable to initialize interface")
-
-    /* Mark "top" of interface as initialized, too */
-    H5G_top_package_initialize_s = TRUE;
-
-done:
-    FUNC_LEAVE_NOAPI(ret_value)
-} /* end H5G__init_package() */
-
-/*-------------------------------------------------------------------------
- * Function:	H5G_top_term_package
- *
- * Purpose:	Close the "top" of the interface, releasing IDs, etc.
- *
- * Return:	Success:	Positive if anything is done that might
- *				affect other interfaces; zero otherwise.
- * 		Failure:	Negative.
- *
- * Programmer:	Quincey Koziol
- *		Sunday, September	13, 2015
- *
- *-------------------------------------------------------------------------
- */
-int
-H5G_top_term_package(void)
-{
-    int n = 0;
-
-    FUNC_ENTER_NOAPI_NOINIT_NOERR
-
-    if (H5G_top_package_initialize_s) {
-        if (H5I_nmembers(H5I_GROUP) > 0) {
-            (void)H5I_clear_type(H5I_GROUP, FALSE, FALSE);
-            n++; /*H5I*/
-        }        /* end if */
-
-        /* Mark closed */
-        if (0 == n)
-            H5G_top_package_initialize_s = FALSE;
-    } /* end if */
-
-    FUNC_LEAVE_NOAPI(n)
-} /* end H5G_top_term_package() */
-
-/*-------------------------------------------------------------------------
- * Function:	H5G_term_package
- *
- * Purpose:	Terminates the H5G interface
- *
- * Note:	Finishes shutting down the interface, after
- *		H5G_top_term_package() is called
- *
- * Return:	Success:	Positive if anything is done that might
- *				affect other interfaces; zero otherwise.
- * 		Failure:	Negative.
- *
- * Programmer:	Robb Matzke
- *		Monday, January	 5, 1998
+ * Return:      Success:    A group ID
+ *              Failure:    H5I_INVALID_HID
  *
  *-------------------------------------------------------------------------
  */
-int
-H5G_term_package(void)
+static hid_t
+H5G__create_api_common(hid_t loc_id, const char *name, hid_t lcpl_id, hid_t gcpl_id, hid_t gapl_id,
+                       void **token_ptr, H5VL_object_t **_vol_obj_ptr)
 {
-    int n = 0;
-
-    FUNC_ENTER_NOAPI_NOINIT_NOERR
+    void *          grp         = NULL; /* Structure for new group */
+    H5VL_object_t * tmp_vol_obj = NULL; /* Object for loc_id */
+    H5VL_object_t **vol_obj_ptr =
+        (_vol_obj_ptr ? _vol_obj_ptr : &tmp_vol_obj); /* Ptr to object ptr for loc_id */
+    H5VL_loc_params_t loc_params;                     /* Location parameters for object access */
+    hid_t             ret_value = H5I_INVALID_HID;    /* Return value */
 
-    if (H5_PKG_INIT_VAR) {
-        /* Sanity checks */
-        HDassert(0 == H5I_nmembers(H5I_GROUP));
-        HDassert(FALSE == H5G_top_package_initialize_s);
-
-        /* Destroy the group object id group */
-        n += (H5I_dec_type_ref(H5I_GROUP) > 0);
+    FUNC_ENTER_STATIC
 
-        /* Mark closed */
-        if (0 == n)
-            H5_PKG_INIT_VAR = FALSE;
-    } /* end if */
+    /* Check arguments */
+    if (!name)
+        HGOTO_ERROR(H5E_ARGS, H5E_BADVALUE, H5I_INVALID_HID, "name parameter cannot be NULL")
+    if (!*name)
+        HGOTO_ERROR(H5E_ARGS, H5E_BADVALUE, H5I_INVALID_HID, "name parameter cannot be an empty string")
 
-    FUNC_LEAVE_NOAPI(n)
-} /* end H5G_term_package() */
+    /* Set up object access arguments */
+    if (H5VL_setup_acc_args(loc_id, H5P_CLS_GACC, TRUE, &gapl_id, vol_obj_ptr, &loc_params) < 0)
+        HGOTO_ERROR(H5E_SYM, H5E_CANTSET, H5I_INVALID_HID, "can't set object access arguments")
 
-/*-------------------------------------------------------------------------
- * Function:    H5G__close_cb
- *
- * Purpose:     Called when the ref count reaches zero on the group's ID
- *
- * Return:      SUCCEED/FAIL
- *
- *-------------------------------------------------------------------------
- */
-static herr_t
-H5G__close_cb(H5VL_object_t *grp_vol_obj)
-{
-    herr_t ret_value = SUCCEED; /* Return value */
+    /* Check link creation property list */
+    if (H5P_DEFAULT == lcpl_id)
+        lcpl_id = H5P_LINK_CREATE_DEFAULT;
+    else if (TRUE != H5P_isa_class(lcpl_id, H5P_LINK_CREATE))
+        HGOTO_ERROR(H5E_ARGS, H5E_BADTYPE, H5I_INVALID_HID, "not a link creation property list")
 
-    FUNC_ENTER_STATIC
+    /* Check group creation property list */
+    if (H5P_DEFAULT == gcpl_id)
+        gcpl_id = H5P_GROUP_CREATE_DEFAULT;
+    else if (TRUE != H5P_isa_class(gcpl_id, H5P_GROUP_CREATE))
+        HGOTO_ERROR(H5E_ARGS, H5E_BADTYPE, H5I_INVALID_HID, "not a group creation property list")
 
-    /* Sanity check */
-    HDassert(grp_vol_obj);
+    /* Set the LCPL for the API context */
+    H5CX_set_lcpl(lcpl_id);
 
-    /* Close the group */
-    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")
+    /* Create the group */
+    if (NULL == (grp = H5VL_group_create(*vol_obj_ptr, &loc_params, name, lcpl_id, gcpl_id, gapl_id,
+                                         H5P_DATASET_XFER_DEFAULT, token_ptr)))
+        HGOTO_ERROR(H5E_SYM, H5E_CANTINIT, H5I_INVALID_HID, "unable to create group")
 
-    /* Free the VOL object */
-    if (H5VL_free_object(grp_vol_obj) < 0)
-        HGOTO_ERROR(H5E_SYM, H5E_CANTDEC, FAIL, "unable to free VOL object")
+    /* Get an ID for the group */
+    if ((ret_value = H5VL_register(H5I_GROUP, grp, (*vol_obj_ptr)->connector, TRUE)) < 0)
+        HGOTO_ERROR(H5E_SYM, H5E_CANTREGISTER, H5I_INVALID_HID, "unable to get ID for group handle")
 
 done:
+    if (H5I_INVALID_HID == ret_value)
+        if (grp && H5VL_group_close(*vol_obj_ptr, H5P_DATASET_XFER_DEFAULT, H5_REQUEST_NULL) < 0)
+            HDONE_ERROR(H5E_SYM, H5E_CLOSEERROR, H5I_INVALID_HID, "unable to release group")
+
     FUNC_LEAVE_NOAPI(ret_value)
-} /* end H5G__close_cb() */
+} /* end H5G__create_api_common() */
 
 /*-------------------------------------------------------------------------
  * Function:    H5Gcreate2
@@ -324,63 +222,65 @@ done:
 hid_t
 H5Gcreate2(hid_t loc_id, const char *name, hid_t lcpl_id, hid_t gcpl_id, hid_t gapl_id)
 {
-    void *            grp     = NULL; /* Structure for new group */
-    H5VL_object_t *   vol_obj = NULL; /* object of loc_id */
-    H5VL_loc_params_t loc_params;
-    hid_t             ret_value = H5I_INVALID_HID; /* Return value */
+    hid_t ret_value = H5I_INVALID_HID; /* Return value */
 
     FUNC_ENTER_API(H5I_INVALID_HID)
     H5TRACE5("i", "i*siii", loc_id, name, lcpl_id, gcpl_id, gapl_id);
 
-    /* Check arguments */
-    if (!name)
-        HGOTO_ERROR(H5E_ARGS, H5E_BADVALUE, H5I_INVALID_HID, "name parameter cannot be NULL")
-    if (!*name)
-        HGOTO_ERROR(H5E_ARGS, H5E_BADVALUE, H5I_INVALID_HID, "name parameter cannot be an empty string")
-
-    /* Check link creation property list */
-    if (H5P_DEFAULT == lcpl_id)
-        lcpl_id = H5P_LINK_CREATE_DEFAULT;
-    else if (TRUE != H5P_isa_class(lcpl_id, H5P_LINK_CREATE))
-        HGOTO_ERROR(H5E_ARGS, H5E_BADTYPE, H5I_INVALID_HID, "not a link creation property list")
-
-    /* Check group creation property list */
-    if (H5P_DEFAULT == gcpl_id)
-        gcpl_id = H5P_GROUP_CREATE_DEFAULT;
-    else if (TRUE != H5P_isa_class(gcpl_id, H5P_GROUP_CREATE))
-        HGOTO_ERROR(H5E_ARGS, H5E_BADTYPE, H5I_INVALID_HID, "not a group creation property list")
-
-    /* Set the LCPL for the API context */
-    H5CX_set_lcpl(lcpl_id);
+    /* Create the group synchronously */
+    if ((ret_value = H5G__create_api_common(loc_id, name, lcpl_id, gcpl_id, gapl_id, NULL, NULL)) < 0)
+        HGOTO_ERROR(H5E_SYM, H5E_CANTCREATE, H5I_INVALID_HID, "unable to synchronously create group")
 
-    /* Verify access property list and set up collective metadata if appropriate */
-    if (H5CX_set_apl(&gapl_id, H5P_CLS_GACC, loc_id, TRUE) < 0)
-        HGOTO_ERROR(H5E_SYM, H5E_CANTSET, H5I_INVALID_HID, "can't set access property list info")
+done:
+    FUNC_LEAVE_API(ret_value)
+} /* end H5Gcreate2() */
 
-    /* Get the location object */
-    if (NULL == (vol_obj = (H5VL_object_t *)H5I_object(loc_id)))
-        HGOTO_ERROR(H5E_ARGS, H5E_BADTYPE, H5I_INVALID_HID, "invalid location identifier")
+/*-------------------------------------------------------------------------
+ * Function:    H5Gcreate_async
+ *
+ * Purpose:     Asynchronous version of H5Gcreate
+ *
+ * Return:      Success:    A group ID
+ *              Failure:    H5I_INVALID_HID
+ *
+ *-------------------------------------------------------------------------
+ */
+hid_t
+H5Gcreate_async(const char *app_file, const char *app_func, unsigned app_line, hid_t loc_id, const char *name,
+                hid_t lcpl_id, hid_t gcpl_id, hid_t gapl_id, hid_t es_id)
+{
+    H5VL_object_t *vol_obj   = NULL;            /* Object for loc_id */
+    void *         token     = NULL;            /* Request token for async operation        */
+    void **        token_ptr = H5_REQUEST_NULL; /* Pointer to request token for async operation        */
+    hid_t          ret_value = H5I_INVALID_HID; /* Return value */
 
-    /* Set the location parameters */
-    loc_params.type     = H5VL_OBJECT_BY_SELF;
-    loc_params.obj_type = H5I_get_type(loc_id);
+    FUNC_ENTER_API(H5I_INVALID_HID)
+    H5TRACE9("i", "*s*sIui*siiii", app_file, app_func, app_line, loc_id, name, lcpl_id, gcpl_id, gapl_id,
+             es_id);
 
-    /* Create the group */
-    if (NULL == (grp = H5VL_group_create(vol_obj, &loc_params, name, lcpl_id, gcpl_id, gapl_id,
-                                         H5P_DATASET_XFER_DEFAULT, H5_REQUEST_NULL)))
-        HGOTO_ERROR(H5E_SYM, H5E_CANTINIT, H5I_INVALID_HID, "unable to create group")
+    /* Set up request token pointer for asynchronous operation */
+    if (H5ES_NONE != es_id)
+        token_ptr = &token; /* Point at token for VOL connector to set up */
 
-    /* Get an atom for the group */
-    if ((ret_value = H5VL_register(H5I_GROUP, grp, vol_obj->connector, TRUE)) < 0)
-        HGOTO_ERROR(H5E_SYM, H5E_CANTREGISTER, H5I_INVALID_HID, "unable to atomize group handle")
+    /* Create the group asynchronously */
+    if ((ret_value = H5G__create_api_common(loc_id, name, lcpl_id, gcpl_id, gapl_id, token_ptr, &vol_obj)) <
+        0)
+        HGOTO_ERROR(H5E_SYM, H5E_CANTCREATE, H5I_INVALID_HID, "unable to asynchronously create group")
+
+    /* If a token was created, add the token to the event set */
+    if (NULL != token)
+        /* clang-format off */
+        if (H5ES_insert(es_id, vol_obj->connector, token,
+                        H5ARG_TRACE9(FUNC, "*s*sIui*siiii", app_file, app_func, app_line, loc_id, name, lcpl_id, gcpl_id, gapl_id, es_id)) < 0) {
+            /* clang-format on */
+            if (H5I_dec_app_ref_always_close(ret_value) < 0)
+                HDONE_ERROR(H5E_SYM, H5E_CANTDEC, H5I_INVALID_HID, "can't decrement count on group ID")
+            HGOTO_ERROR(H5E_SYM, H5E_CANTINSERT, H5I_INVALID_HID, "can't insert token into event set")
+        } /* end if */
 
 done:
-    if (H5I_INVALID_HID == ret_value)
-        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)
-} /* end H5Gcreate2() */
+} /* end H5Gcreate_async() */
 
 /*-------------------------------------------------------------------------
  * Function:    H5Gcreate_anon
@@ -417,9 +317,9 @@ done:
 hid_t
 H5Gcreate_anon(hid_t loc_id, hid_t gcpl_id, hid_t gapl_id)
 {
-    void *            grp     = NULL; /* Structure for new group */
-    H5VL_object_t *   vol_obj = NULL; /* Object for loc_id */
-    H5VL_loc_params_t loc_params;
+    void *            grp     = NULL;              /* Structure for new group */
+    H5VL_object_t *   vol_obj = NULL;              /* Object for loc_id */
+    H5VL_loc_params_t loc_params;                  /* Location parameters for object access */
     hid_t             ret_value = H5I_INVALID_HID; /* Return value */
 
     FUNC_ENTER_API(H5I_INVALID_HID)
@@ -448,9 +348,9 @@ H5Gcreate_anon(hid_t loc_id, hid_t gcpl_id, hid_t gapl_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 */
+    /* Get an ID for the group */
     if ((ret_value = H5VL_register(H5I_GROUP, grp, vol_obj->connector, TRUE)) < 0)
-        HGOTO_ERROR(H5E_SYM, H5E_CANTREGISTER, H5I_INVALID_HID, "unable to atomize group handle")
+        HGOTO_ERROR(H5E_SYM, H5E_CANTREGISTER, H5I_INVALID_HID, "unable to get ID for group handle")
 
 done:
     /* Cleanup on failure */
@@ -462,30 +362,27 @@ done:
 } /* end H5Gcreate_anon() */
 
 /*-------------------------------------------------------------------------
- * Function:    H5Gopen2
- *
- * Purpose:     Opens an existing group for modification.  When finished,
- *              call H5Gclose() to close it and release resources.
- *
- *              This function allows the user the pass in a Group Access
- *              Property List, which H5Gopen1() does not.
+ * Function:    H5G__open_api_common
  *
- * Return:      Success:    Object ID of the group
+ * Purpose:     This is the common function for opening HDF5 groups.
  *
+ * Return:      Success:    A group ID
  *              Failure:    H5I_INVALID_HID
  *
  *-------------------------------------------------------------------------
  */
-hid_t
-H5Gopen2(hid_t loc_id, const char *name, hid_t gapl_id)
+static hid_t
+H5G__open_api_common(hid_t loc_id, const char *name, hid_t gapl_id, void **token_ptr,
+                     H5VL_object_t **_vol_obj_ptr)
 {
-    void *            grp     = NULL; /* Group opened */
-    H5VL_object_t *   vol_obj = NULL; /* object of loc_id */
-    H5VL_loc_params_t loc_params;
-    hid_t             ret_value = H5I_INVALID_HID; /* Return value */
+    void *          grp         = NULL; /* Group opened */
+    H5VL_object_t * tmp_vol_obj = NULL; /* Object for loc_id */
+    H5VL_object_t **vol_obj_ptr =
+        (_vol_obj_ptr ? _vol_obj_ptr : &tmp_vol_obj); /* Ptr to object ptr for loc_id */
+    H5VL_loc_params_t loc_params;                     /* Location parameters for object access */
+    hid_t             ret_value = H5I_INVALID_HID;    /* Return value */
 
-    FUNC_ENTER_API(H5I_INVALID_HID)
-    H5TRACE3("i", "i*si", loc_id, name, gapl_id);
+    FUNC_ENTER_STATIC
 
     /* Check args */
     if (!name)
@@ -493,35 +390,103 @@ H5Gopen2(hid_t loc_id, const char *name, hid_t gapl_id)
     if (!*name)
         HGOTO_ERROR(H5E_ARGS, H5E_BADVALUE, H5I_INVALID_HID, "name parameter cannot be an empty string")
 
-    /* Verify access property list and set up collective metadata if appropriate */
-    if (H5CX_set_apl(&gapl_id, H5P_CLS_GACC, loc_id, FALSE) < 0)
-        HGOTO_ERROR(H5E_SYM, H5E_CANTSET, H5I_INVALID_HID, "can't set access property list info")
-
-    /* Get the location object */
-    if (NULL == (vol_obj = (H5VL_object_t *)H5I_object(loc_id)))
-        HGOTO_ERROR(H5E_ARGS, H5E_BADTYPE, H5I_INVALID_HID, "invalid location identifier")
-
-    /* Open the group */
-    loc_params.type     = H5VL_OBJECT_BY_SELF;
-    loc_params.obj_type = H5I_get_type(loc_id);
+    /* Set up object access arguments */
+    if (H5VL_setup_acc_args(loc_id, H5P_CLS_GACC, FALSE, &gapl_id, vol_obj_ptr, &loc_params) < 0)
+        HGOTO_ERROR(H5E_SYM, H5E_CANTSET, H5I_INVALID_HID, "can't set object access arguments")
 
-    if (NULL == (grp = H5VL_group_open(vol_obj, &loc_params, name, gapl_id, H5P_DATASET_XFER_DEFAULT,
-                                       H5_REQUEST_NULL)))
+    if (NULL == (grp = H5VL_group_open(*vol_obj_ptr, &loc_params, name, gapl_id, H5P_DATASET_XFER_DEFAULT,
+                                       token_ptr)))
         HGOTO_ERROR(H5E_SYM, H5E_CANTOPENOBJ, H5I_INVALID_HID, "unable to open group")
 
     /* Register an ID for the group */
-    if ((ret_value = H5VL_register(H5I_GROUP, grp, vol_obj->connector, TRUE)) < 0)
+    if ((ret_value = H5VL_register(H5I_GROUP, grp, (*vol_obj_ptr)->connector, TRUE)) < 0)
         HGOTO_ERROR(H5E_SYM, H5E_CANTREGISTER, H5I_INVALID_HID, "unable to register group")
 
 done:
     if (H5I_INVALID_HID == ret_value)
-        if (grp && H5VL_group_close(vol_obj, H5P_DATASET_XFER_DEFAULT, H5_REQUEST_NULL) < 0)
+        if (grp && H5VL_group_close(*vol_obj_ptr, H5P_DATASET_XFER_DEFAULT, H5_REQUEST_NULL) < 0)
             HDONE_ERROR(H5E_SYM, H5E_CLOSEERROR, H5I_INVALID_HID, "unable to release group")
 
+    FUNC_LEAVE_NOAPI(ret_value)
+} /* H5G__open_api_common() */
+
+/*-------------------------------------------------------------------------
+ * Function:    H5Gopen2
+ *
+ * Purpose:     Opens an existing group for modification.  When finished,
+ *              call H5Gclose() to close it and release resources.
+ *
+ *              This function allows the user the pass in a Group Access
+ *              Property List, which H5Gopen1() does not.
+ *
+ * Return:      Success:    Object ID of the group
+ *
+ *              Failure:    H5I_INVALID_HID
+ *
+ *-------------------------------------------------------------------------
+ */
+hid_t
+H5Gopen2(hid_t loc_id, const char *name, hid_t gapl_id)
+{
+    hid_t ret_value = H5I_INVALID_HID; /* Return value */
+
+    FUNC_ENTER_API(H5I_INVALID_HID)
+    H5TRACE3("i", "i*si", loc_id, name, gapl_id);
+
+    /* Open the group synchronously */
+    if ((ret_value = H5G__open_api_common(loc_id, name, gapl_id, NULL, NULL)) < 0)
+        HGOTO_ERROR(H5E_SYM, H5E_CANTCREATE, H5I_INVALID_HID, "unable to synchronously open group")
+
+done:
     FUNC_LEAVE_API(ret_value)
 } /* end H5Gopen2() */
 
 /*-------------------------------------------------------------------------
+ * Function:    H5Gopen_async
+ *
+ * Purpose:     Asynchronous version of H5Gopen2
+ *
+ * Return:      Success:    A group ID
+ *              Failure:    H5I_INVALID_HID
+ *
+ *-------------------------------------------------------------------------
+ */
+hid_t
+H5Gopen_async(const char *app_file, const char *app_func, unsigned app_line, hid_t loc_id, const char *name,
+              hid_t gapl_id, hid_t es_id)
+{
+    H5VL_object_t *vol_obj   = NULL;            /* Object for loc_id */
+    void *         token     = NULL;            /* Request token for async operation        */
+    void **        token_ptr = H5_REQUEST_NULL; /* Pointer to request token for async operation        */
+    hid_t          ret_value = H5I_INVALID_HID; /* Return value */
+
+    FUNC_ENTER_API(H5I_INVALID_HID)
+    H5TRACE7("i", "*s*sIui*sii", app_file, app_func, app_line, loc_id, name, gapl_id, es_id);
+
+    /* Set up request token pointer for asynchronous operation */
+    if (H5ES_NONE != es_id)
+        token_ptr = &token; /* Point at token for VOL connector to set up */
+
+    /* Open the group asynchronously */
+    if ((ret_value = H5G__open_api_common(loc_id, name, gapl_id, token_ptr, &vol_obj)) < 0)
+        HGOTO_ERROR(H5E_SYM, H5E_CANTCREATE, H5I_INVALID_HID, "unable to asynchronously open group")
+
+    /* If a token was created, add the token to the event set */
+    if (NULL != token)
+        /* clang-format off */
+        if (H5ES_insert(es_id, vol_obj->connector, token,
+                        H5ARG_TRACE7(FUNC, "*s*sIui*sii", app_file, app_func, app_line, loc_id, name, gapl_id, es_id)) < 0) {
+            /* clang-format on */
+            if (H5I_dec_app_ref_always_close(ret_value) < 0)
+                HDONE_ERROR(H5E_SYM, H5E_CANTDEC, H5I_INVALID_HID, "can't decrement count on group ID")
+            HGOTO_ERROR(H5E_SYM, H5E_CANTINSERT, H5I_INVALID_HID, "can't insert token into event set")
+        } /* end if */
+
+done:
+    FUNC_LEAVE_API(ret_value)
+} /* end H5Gopen_async() */
+
+/*-------------------------------------------------------------------------
  * Function:    H5Gget_create_plist
  *
  * Purpose:     Returns a copy of the group creation property list.
@@ -557,24 +522,27 @@ done:
 } /* end H5Gget_create_plist() */
 
 /*-------------------------------------------------------------------------
- * Function:    H5Gget_info
+ * Function:    H5G__get_info_api_common
  *
- * Purpose:     Retrieve information about a group.
+ * Purpose:     This is the common function for retrieving information
+ *              about a group.
  *
  * Return:      SUCCEED/FAIL
  *
  *-------------------------------------------------------------------------
  */
-herr_t
-H5Gget_info(hid_t loc_id, H5G_info_t *group_info)
+static herr_t
+H5G__get_info_api_common(hid_t loc_id, H5G_info_t *group_info /*out*/, void **token_ptr,
+                         H5VL_object_t **_vol_obj_ptr)
 {
-    H5VL_object_t *   vol_obj;
-    H5I_type_t        id_type; /* Type of ID */
-    H5VL_loc_params_t loc_params;
-    herr_t            ret_value = SUCCEED; /* Return value */
+    H5VL_object_t * tmp_vol_obj = NULL; /* Object for loc_id */
+    H5VL_object_t **vol_obj_ptr =
+        (_vol_obj_ptr ? _vol_obj_ptr : &tmp_vol_obj); /* Ptr to object ptr for loc_id */
+    H5VL_loc_params_t loc_params;                     /* Location parameters for object access */
+    H5I_type_t        id_type;                        /* Type of ID */
+    herr_t            ret_value = SUCCEED;            /* Return value */
 
-    FUNC_ENTER_API(FAIL)
-    H5TRACE2("e", "i*!", loc_id, group_info);
+    FUNC_ENTER_STATIC
 
     /* Check args */
     id_type = H5I_get_type(loc_id);
@@ -583,132 +551,305 @@ H5Gget_info(hid_t loc_id, H5G_info_t *group_info)
     if (!group_info)
         HGOTO_ERROR(H5E_ARGS, H5E_BADVALUE, FAIL, "group_info parameter cannot be NULL")
 
-    /* Get group location */
-    if (NULL == (vol_obj = (H5VL_object_t *)H5I_object(loc_id)))
-        HGOTO_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "invalid location identifier")
+    /* Set up object access arguments */
+    if (H5VL_setup_self_args(loc_id, vol_obj_ptr, &loc_params) < 0)
+        HGOTO_ERROR(H5E_SYM, H5E_CANTSET, FAIL, "can't set object access arguments")
 
-    /* Retrieve the group's information */
-    loc_params.type     = H5VL_OBJECT_BY_SELF;
-    loc_params.obj_type = id_type;
-    if (H5VL_group_get(vol_obj, H5VL_GROUP_GET_INFO, H5P_DATASET_XFER_DEFAULT, H5_REQUEST_NULL, &loc_params,
+    /* Retrieve group information */
+    if (H5VL_group_get(*vol_obj_ptr, H5VL_GROUP_GET_INFO, H5P_DATASET_XFER_DEFAULT, token_ptr, &loc_params,
                        group_info) < 0)
         HGOTO_ERROR(H5E_SYM, H5E_CANTGET, FAIL, "unable to get group info")
 
 done:
+    FUNC_LEAVE_NOAPI(ret_value)
+} /* H5G__get_info_api_common() */
+
+/*-------------------------------------------------------------------------
+ * Function:    H5Gget_info
+ *
+ * Purpose:     Retrieve information about a group.
+ *
+ * Return:      SUCCEED/FAIL
+ *
+ *-------------------------------------------------------------------------
+ */
+herr_t
+H5Gget_info(hid_t loc_id, H5G_info_t *group_info /*out*/)
+{
+    herr_t ret_value = SUCCEED; /* Return value */
+
+    FUNC_ENTER_API(FAIL)
+    H5TRACE2("e", "ix", loc_id, group_info);
+
+    /* Retrieve group information synchronously */
+    if (H5G__get_info_api_common(loc_id, group_info, NULL, NULL) < 0)
+        HGOTO_ERROR(H5E_SYM, H5E_CANTGET, FAIL, "unable to synchronously get group info")
+
+done:
     FUNC_LEAVE_API(ret_value)
 } /* end H5Gget_info() */
 
 /*-------------------------------------------------------------------------
- * Function:    H5Gget_info_by_name
+ * Function:    H5Gget_info_async
  *
- * Purpose:     Retrieve information about a group, where the group is
- *              identified by name instead of ID.
+ * Purpose:     Asynchronous version of H5Gget_info
  *
  * Return:      SUCCEED/FAIL
  *
  *-------------------------------------------------------------------------
  */
 herr_t
-H5Gget_info_by_name(hid_t loc_id, const char *name, H5G_info_t *group_info, hid_t lapl_id)
+H5Gget_info_async(const char *app_file, const char *app_func, unsigned app_line, hid_t loc_id,
+                  H5G_info_t *group_info /*out*/, hid_t es_id)
 {
-    H5VL_object_t *   vol_obj;
-    H5VL_loc_params_t loc_params;
-    herr_t            ret_value = SUCCEED; /* Return value */
+    H5VL_object_t *vol_obj   = NULL;            /* Object for loc_id */
+    void *         token     = NULL;            /* Request token for async operation        */
+    void **        token_ptr = H5_REQUEST_NULL; /* Pointer to request token for async operation        */
+    herr_t         ret_value = SUCCEED;         /* Return value */
 
     FUNC_ENTER_API(FAIL)
-    H5TRACE4("e", "i*s*!i", loc_id, name, group_info, lapl_id);
+    H5TRACE6("e", "*s*sIuixi", app_file, app_func, app_line, loc_id, group_info, es_id);
+
+    /* Set up request token pointer for asynchronous operation */
+    if (H5ES_NONE != es_id)
+        token_ptr = &token; /* Point at token for VOL connector to set up */
+
+    /* Retrieve group information asynchronously */
+    if (H5G__get_info_api_common(loc_id, group_info, token_ptr, &vol_obj) < 0)
+        HGOTO_ERROR(H5E_SYM, H5E_CANTGET, FAIL, "unable to asynchronously get group info")
+
+    /* If a token was created, add the token to the event set */
+    if (NULL != token)
+        /* clang-format off */
+        if (H5ES_insert(es_id, vol_obj->connector, token,
+                H5ARG_TRACE6(FUNC, "*s*sIuixi", app_file, app_func, app_line, loc_id, group_info, es_id)) < 0)
+            /* clang-format on */
+            HGOTO_ERROR(H5E_SYM, H5E_CANTINSERT, FAIL, "can't insert token into event set")
+
+done:
+    FUNC_LEAVE_API(ret_value)
+} /* H5Gget_info_async() */
+
+/*-------------------------------------------------------------------------
+ * Function:    H5G__get_info_by_name_api_common
+ *
+ * Purpose:     This is the common function for retrieving information
+ *              about a group.
+ *
+ * Return:      SUCCEED/FAIL
+ *
+ *-------------------------------------------------------------------------
+ */
+static herr_t
+H5G__get_info_by_name_api_common(hid_t loc_id, const char *name, H5G_info_t *group_info /*out*/,
+                                 hid_t lapl_id, void **token_ptr, H5VL_object_t **_vol_obj_ptr)
+{
+    H5VL_object_t * tmp_vol_obj = NULL; /* Object for loc_id */
+    H5VL_object_t **vol_obj_ptr =
+        (_vol_obj_ptr ? _vol_obj_ptr : &tmp_vol_obj); /* Ptr to object ptr for loc_id */
+    H5VL_loc_params_t loc_params;                     /* Location parameters for object access */
+    herr_t            ret_value = SUCCEED;            /* Return value */
+
+    FUNC_ENTER_STATIC
 
     /* Check args */
-    if (!name)
-        HGOTO_ERROR(H5E_ARGS, H5E_BADVALUE, FAIL, "name parameter cannot be NULL")
-    if (!*name)
-        HGOTO_ERROR(H5E_ARGS, H5E_BADVALUE, FAIL, "name parameter cannot be an empty string")
     if (!group_info)
         HGOTO_ERROR(H5E_ARGS, H5E_BADVALUE, FAIL, "group_info parameter cannot be NULL")
 
-    /* Verify access property list and set up collective metadata if appropriate */
-    if (H5CX_set_apl(&lapl_id, H5P_CLS_LACC, loc_id, FALSE) < 0)
-        HGOTO_ERROR(H5E_SYM, H5E_CANTSET, FAIL, "can't set access property list info")
+    /* Set up object access arguments */
+    if (H5VL_setup_name_args(loc_id, name, H5P_CLS_LACC, FALSE, lapl_id, vol_obj_ptr, &loc_params) < 0)
+        HGOTO_ERROR(H5E_SYM, H5E_CANTSET, FAIL, "can't set object access arguments")
 
-    /* Get the location object */
-    if (NULL == (vol_obj = (H5VL_object_t *)H5I_object(loc_id)))
-        HGOTO_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "invalid location identifier")
+    /* Retrieve group information */
+    if (H5VL_group_get(*vol_obj_ptr, H5VL_GROUP_GET_INFO, H5P_DATASET_XFER_DEFAULT, token_ptr, &loc_params,
+                       group_info) < 0)
+        HGOTO_ERROR(H5E_SYM, H5E_CANTGET, FAIL, "unable to get group info")
 
-    /* Set up location parameters */
-    loc_params.type                         = H5VL_OBJECT_BY_NAME;
-    loc_params.loc_data.loc_by_name.name    = name;
-    loc_params.loc_data.loc_by_name.lapl_id = lapl_id;
-    loc_params.obj_type                     = H5I_get_type(loc_id);
+done:
+    FUNC_LEAVE_NOAPI(ret_value)
+} /* H5G__get_info_by_name_api_common() */
 
-    /* Retrieve the group's information */
-    if (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")
+/*-------------------------------------------------------------------------
+ * Function:    H5Gget_info_by_name
+ *
+ * Purpose:     Retrieve information about a group, where the group is
+ *              identified by name instead of ID.
+ *
+ * Return:      SUCCEED/FAIL
+ *
+ *-------------------------------------------------------------------------
+ */
+herr_t
+H5Gget_info_by_name(hid_t loc_id, const char *name, H5G_info_t *group_info /*out*/, hid_t lapl_id)
+{
+    herr_t ret_value = SUCCEED; /* Return value */
+
+    FUNC_ENTER_API(FAIL)
+    H5TRACE4("e", "i*sxi", loc_id, name, group_info, lapl_id);
+
+    /* Retrieve group information synchronously */
+    if (H5G__get_info_by_name_api_common(loc_id, name, group_info, lapl_id, NULL, NULL) < 0)
+        HGOTO_ERROR(H5E_SYM, H5E_CANTGET, FAIL, "can't synchronously retrieve group info")
 
 done:
     FUNC_LEAVE_API(ret_value)
 } /* end H5Gget_info_by_name() */
 
 /*-------------------------------------------------------------------------
- * Function:    H5Gget_info_by_idx
+ * Function:    H5Gget_info_by_name_async
  *
- * Purpose:     Retrieve information about a group, according to the order
- *              of an index.
+ * Purpose:     Asynchronous version of H5Gget_info_by_name
  *
  * Return:      SUCCEED/FAIL
  *
  *-------------------------------------------------------------------------
  */
 herr_t
-H5Gget_info_by_idx(hid_t loc_id, const char *group_name, H5_index_t idx_type, H5_iter_order_t order,
-                   hsize_t n, H5G_info_t *group_info, hid_t lapl_id)
+H5Gget_info_by_name_async(const char *app_file, const char *app_func, unsigned app_line, hid_t loc_id,
+                          const char *name, H5G_info_t *group_info /*out*/, hid_t lapl_id, hid_t es_id)
 {
-    H5VL_object_t *   vol_obj;
-    H5VL_loc_params_t loc_params;
-    herr_t            ret_value = SUCCEED; /* Return value */
+    H5VL_object_t *vol_obj   = NULL;            /* Object for loc_id */
+    void *         token     = NULL;            /* Request token for async operation        */
+    void **        token_ptr = H5_REQUEST_NULL; /* Pointer to request token for async operation        */
+    herr_t         ret_value = SUCCEED;         /* Return value */
 
     FUNC_ENTER_API(FAIL)
-    H5TRACE7("e", "i*sIiIoh*!i", loc_id, group_name, idx_type, order, n, group_info, lapl_id);
+    H5TRACE8("e", "*s*sIui*sxii", app_file, app_func, app_line, loc_id, name, group_info, lapl_id, es_id);
+
+    /* Set up request token pointer for asynchronous operation */
+    if (H5ES_NONE != es_id)
+        token_ptr = &token; /* Point at token for VOL connector to set up */
+
+    /* Retrieve group information asynchronously */
+    if (H5G__get_info_by_name_api_common(loc_id, name, group_info, lapl_id, token_ptr, &vol_obj) < 0)
+        HGOTO_ERROR(H5E_SYM, H5E_CANTGET, FAIL, "can't asynchronously retrieve group info")
+
+    /* If a token was created, add the token to the event set */
+    if (NULL != token)
+        /* clang-format off */
+        if (H5ES_insert(es_id, vol_obj->connector, token,
+                        H5ARG_TRACE8(FUNC, "*s*sIui*sxii", app_file, app_func, app_line, loc_id, name, group_info, lapl_id, es_id)) < 0)
+            /* clang-format on */
+            HGOTO_ERROR(H5E_SYM, H5E_CANTINSERT, FAIL, "can't insert token into event set")
+
+done:
+    FUNC_LEAVE_API(ret_value)
+} /* H5Gget_info_by_name_async() */
+
+/*-------------------------------------------------------------------------
+ * Function:    H5G__get_info_by_idx_api_common
+ *
+ * Purpose:     This is the common function for retrieving information
+ *              about a group.
+ *
+ * Return:      SUCCEED/FAIL
+ *
+ *-------------------------------------------------------------------------
+ */
+static herr_t
+H5G__get_info_by_idx_api_common(hid_t loc_id, const char *group_name, H5_index_t idx_type,
+                                H5_iter_order_t order, hsize_t n, H5G_info_t *group_info /*out*/,
+                                hid_t lapl_id, void **token_ptr, H5VL_object_t **_vol_obj_ptr)
+{
+    H5VL_object_t * tmp_vol_obj = NULL; /* Object for loc_id */
+    H5VL_object_t **vol_obj_ptr =
+        (_vol_obj_ptr ? _vol_obj_ptr : &tmp_vol_obj); /* Ptr to object ptr for loc_id */
+    H5VL_loc_params_t loc_params;                     /* Location parameters for object access */
+    herr_t            ret_value = SUCCEED;            /* Return value */
+
+    FUNC_ENTER_STATIC
 
     /* Check args */
-    if (!group_name)
-        HGOTO_ERROR(H5E_ARGS, H5E_BADVALUE, FAIL, "group_name parameter cannot be NULL")
-    if (!*group_name)
-        HGOTO_ERROR(H5E_ARGS, H5E_BADVALUE, FAIL, "group_name parameter cannot be an empty string")
-    if (idx_type <= H5_INDEX_UNKNOWN || idx_type >= H5_INDEX_N)
-        HGOTO_ERROR(H5E_ARGS, H5E_BADVALUE, FAIL, "invalid index type specified")
-    if (order <= H5_ITER_UNKNOWN || order >= H5_ITER_N)
-        HGOTO_ERROR(H5E_ARGS, H5E_BADVALUE, FAIL, "invalid iteration order specified")
     if (!group_info)
         HGOTO_ERROR(H5E_ARGS, H5E_BADVALUE, FAIL, "group_info parameter cannot be NULL")
 
-    /* Verify access property list and set up collective metadata if appropriate */
-    if (H5CX_set_apl(&lapl_id, H5P_CLS_LACC, loc_id, FALSE) < 0)
-        HGOTO_ERROR(H5E_SYM, H5E_CANTSET, FAIL, "can't set access property list info")
+    /* Set up object access arguments */
+    if (H5VL_setup_idx_args(loc_id, group_name, idx_type, order, n, H5P_CLS_LACC, FALSE, lapl_id, vol_obj_ptr,
+                            &loc_params) < 0)
+        HGOTO_ERROR(H5E_SYM, H5E_CANTSET, FAIL, "can't set object access arguments")
 
-    /* Get the location object */
-    if (NULL == (vol_obj = (H5VL_object_t *)H5I_object(loc_id)))
-        HGOTO_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "invalid location identifier")
-
-    /* Set location parameters */
-    loc_params.type                         = H5VL_OBJECT_BY_IDX;
-    loc_params.loc_data.loc_by_idx.name     = group_name;
-    loc_params.loc_data.loc_by_idx.idx_type = idx_type;
-    loc_params.loc_data.loc_by_idx.order    = order;
-    loc_params.loc_data.loc_by_idx.n        = n;
-    loc_params.loc_data.loc_by_idx.lapl_id  = lapl_id;
-    loc_params.obj_type                     = H5I_get_type(loc_id);
-
-    /* Retrieve the group's information */
-    if (H5VL_group_get(vol_obj, H5VL_GROUP_GET_INFO, H5P_DATASET_XFER_DEFAULT, H5_REQUEST_NULL, &loc_params,
+    /* Retrieve group information */
+    if (H5VL_group_get(*vol_obj_ptr, H5VL_GROUP_GET_INFO, H5P_DATASET_XFER_DEFAULT, token_ptr, &loc_params,
                        group_info) < 0)
-        HGOTO_ERROR(H5E_SYM, H5E_CANTGET, FAIL, "can't retrieve group info")
+        HGOTO_ERROR(H5E_SYM, H5E_CANTGET, FAIL, "unable to get group info")
+
+done:
+    FUNC_LEAVE_NOAPI(ret_value)
+} /* H5G__get_info_by_idx_api_common() */
+
+/*-------------------------------------------------------------------------
+ * Function:    H5Gget_info_by_idx
+ *
+ * Purpose:     Retrieve information about a group, according to the order
+ *              of an index.
+ *
+ * Return:      SUCCEED/FAIL
+ *
+ *-------------------------------------------------------------------------
+ */
+herr_t
+H5Gget_info_by_idx(hid_t loc_id, const char *group_name, H5_index_t idx_type, H5_iter_order_t order,
+                   hsize_t n, H5G_info_t *group_info /*out*/, hid_t lapl_id)
+{
+    herr_t ret_value = SUCCEED; /* Return value */
+
+    FUNC_ENTER_API(FAIL)
+    H5TRACE7("e", "i*sIiIohxi", loc_id, group_name, idx_type, order, n, group_info, lapl_id);
+
+    /* Retrieve group information synchronously */
+    if (H5G__get_info_by_idx_api_common(loc_id, group_name, idx_type, order, n, group_info, lapl_id, NULL,
+                                        NULL) < 0)
+        HGOTO_ERROR(H5E_SYM, H5E_CANTGET, FAIL, "can't synchronously retrieve group info")
 
 done:
     FUNC_LEAVE_API(ret_value)
 } /* end H5Gget_info_by_idx() */
 
 /*-------------------------------------------------------------------------
+ * Function:    H5Gget_info_by_idx_async
+ *
+ * Purpose:     Asynchronous version of H5Gget_info_by_idx
+ *
+ * Return:      SUCCEED/FAIL
+ *
+ *-------------------------------------------------------------------------
+ */
+herr_t
+H5Gget_info_by_idx_async(const char *app_file, const char *app_func, unsigned app_line, hid_t loc_id,
+                         const char *group_name, H5_index_t idx_type, H5_iter_order_t order, hsize_t n,
+                         H5G_info_t *group_info /*out*/, hid_t lapl_id, hid_t es_id)
+{
+    H5VL_object_t *vol_obj   = NULL;            /* Object for loc_id */
+    void *         token     = NULL;            /* Request token for async operation        */
+    void **        token_ptr = H5_REQUEST_NULL; /* Pointer to request token for async operation        */
+    herr_t         ret_value = SUCCEED;         /* Return value */
+
+    FUNC_ENTER_API(FAIL)
+    H5TRACE11("e", "*s*sIui*sIiIohxii", app_file, app_func, app_line, loc_id, group_name, idx_type, order, n,
+              group_info, lapl_id, es_id);
+
+    /* Set up request token pointer for asynchronous operation */
+    if (H5ES_NONE != es_id)
+        token_ptr = &token; /* Point at token for VOL connector to set up */
+
+    /* Retrieve group information asynchronously */
+    if (H5G__get_info_by_idx_api_common(loc_id, group_name, idx_type, order, n, group_info, lapl_id,
+                                        token_ptr, &vol_obj) < 0)
+        HGOTO_ERROR(H5E_SYM, H5E_CANTGET, FAIL, "can't asynchronously retrieve group info")
+
+    /* If a token was created, add the token to the event set */
+    if (NULL != token)
+        /* clang-format off */
+        if (H5ES_insert(es_id, vol_obj->connector, token,
+                        H5ARG_TRACE11(FUNC, "*s*sIui*sIiIohxii", app_file, app_func, app_line, loc_id, group_name, idx_type, order, n, group_info, lapl_id, es_id)) < 0)
+            /* clang-format on */
+            HGOTO_ERROR(H5E_SYM, H5E_CANTINSERT, FAIL, "can't insert token into event set")
+
+done:
+    FUNC_LEAVE_API(ret_value)
+} /* H5Gget_info_by_idx_async() */
+
+/*-------------------------------------------------------------------------
  * Function:    H5Gclose
  *
  * Purpose:     Closes the specified group. The group ID will no longer be
@@ -726,21 +867,82 @@ H5Gclose(hid_t group_id)
     FUNC_ENTER_API(FAIL)
     H5TRACE1("e", "i", group_id);
 
-    /* Check args */
-    if (NULL == H5I_object_verify(group_id, H5I_GROUP))
-        HGOTO_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "not a group")
+    /* Check arguments */
+    if (H5I_GROUP != H5I_get_type(group_id))
+        HGOTO_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "not a group ID")
 
-    /* Decrement the counter on the group atom. It will be freed if the count
+    /* Decrement the counter on the group ID. It will be freed if the count
      * reaches zero.
      */
     if (H5I_dec_app_ref(group_id) < 0)
-        HGOTO_ERROR(H5E_SYM, H5E_CANTRELEASE, FAIL, "unable to close group")
+        HGOTO_ERROR(H5E_SYM, H5E_CANTDEC, FAIL, "decrementing group ID failed")
 
 done:
     FUNC_LEAVE_API(ret_value)
 } /* end H5Gclose() */
 
 /*-------------------------------------------------------------------------
+ * Function:    H5Gclose_async
+ *
+ * Purpose:     Asynchronous version of H5Gclose
+ *
+ * Return:      SUCCEED/FAIL
+ *
+ *-------------------------------------------------------------------------
+ */
+herr_t
+H5Gclose_async(const char *app_file, const char *app_func, unsigned app_line, hid_t group_id, hid_t es_id)
+{
+    H5VL_object_t *vol_obj   = NULL;            /* Object for loc_id */
+    H5VL_t *       connector = NULL;            /* VOL connector */
+    void *         token     = NULL;            /* Request token for async operation        */
+    void **        token_ptr = H5_REQUEST_NULL; /* Pointer to request token for async operation        */
+    herr_t         ret_value = SUCCEED;         /* Return value                     */
+
+    FUNC_ENTER_API(FAIL)
+    H5TRACE5("e", "*s*sIuii", app_file, app_func, app_line, group_id, es_id);
+
+    /* Check arguments */
+    if (H5I_GROUP != H5I_get_type(group_id))
+        HGOTO_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "not a group ID")
+
+    /* Prepare for possible asynchronous operation */
+    if (H5ES_NONE != es_id) {
+        /* Get group object's connector */
+        if (NULL == (vol_obj = H5VL_vol_object(group_id)))
+            HGOTO_ERROR(H5E_SYM, H5E_CANTGET, FAIL, "can't get VOL object for group")
+
+        /* Increase connector's refcount, so it doesn't get closed if closing
+         * the group closes the file */
+        connector = vol_obj->connector;
+        H5VL_conn_inc_rc(connector);
+
+        /* Point at token for operation to set up */
+        token_ptr = &token;
+    } /* end if */
+
+    /* Decrement the counter on the group ID. It will be freed if the count
+     * reaches zero.
+     */
+    if (H5I_dec_app_ref_async(group_id, token_ptr) < 0)
+        HGOTO_ERROR(H5E_SYM, H5E_CANTDEC, FAIL, "decrementing group ID failed")
+
+    /* If a token was created, add the token to the event set */
+    if (NULL != token)
+        /* clang-format off */
+        if (H5ES_insert(es_id, vol_obj->connector, token,
+                        H5ARG_TRACE5(FUNC, "*s*sIuii", app_file, app_func, app_line, group_id, es_id)) < 0)
+            /* clang-format on */
+            HGOTO_ERROR(H5E_SYM, H5E_CANTINSERT, FAIL, "can't insert token into event set")
+
+done:
+    if (connector && H5VL_conn_dec_rc(connector) < 0)
+        HDONE_ERROR(H5E_SYM, H5E_CANTDEC, FAIL, "can't decrement ref count on connector")
+
+    FUNC_LEAVE_API(ret_value)
+} /* end H5Gclose_async() */
+
+/*-------------------------------------------------------------------------
  * Function:    H5Gflush
  *
  * Purpose:     Flushes all buffers associated with a group to disk.