VFD plugins (#602)

* Implement support for loading of Virtual File Drivers as plugins

Fix plugin caching for VOL connector and VFD plugins

Fix plugin iteration to skip paths that can't be opened

* Enable dynamic loading of VFDs with HDF5_DRIVER environment variable

* Temporarily disable error reporting during H5F_open double file open

* Default to using HDstat in h5_get_file_size for unknown VFDs

* Use macros for some environment variables that HDF5 interprets

* Update "null" and "ctl testing" VFDs

1 files changed, 19 insertions, 5 deletions

diff --git a/test/app_ref.c b/test/app_ref.c
index 09cfb72..2777dc0 100644
--- a/test/app_ref.c
+++ b/test/app_ref.c
@@ -79,11 +79,12 @@ Abrt_Handler(int H5_ATTR_UNUSED sig)
 int
 main(void)
 {
-    hid_t ids[T_NUMCLASSES];
-    hid_t fapl; /* File Access Property List */
-    int   ninc;
-    int   i;
-    char  filename[1024];
+    const char *env_h5_drvr; /* File Driver value from environment */
+    hid_t       ids[T_NUMCLASSES];
+    hid_t       fapl; /* File Access Property List */
+    int         ninc;
+    int         i;
+    char        filename[1024];
 
     h5_reset();
     h5_fixname(FILENAME[0], H5P_DEFAULT, filename, sizeof filename);
@@ -92,6 +93,19 @@ main(void)
 
     TESTING("library shutdown with reference count > 1");
 
+    /* Get the VFD to use */
+    env_h5_drvr = HDgetenv(HDF5_DRIVER);
+    if (env_h5_drvr == NULL)
+        env_h5_drvr = "nomatch";
+
+    /* Don't run this test with the multi/split VFD. A bug in library shutdown
+     * ordering causes problems with the multi VFD when IDs are left dangling.
+     */
+    if (!HDstrcmp(env_h5_drvr, "multi") || !HDstrcmp(env_h5_drvr, "split")) {
+        HDputs("\n -- SKIPPED for incompatible VFD --");
+        return 0;
+    }
+
     /* Create the file */
     if ((ids[T_FILE] = H5Fcreate(filename, H5F_ACC_TRUNC, H5P_DEFAULT, H5P_DEFAULT)) < 0)
         TEST_ERROR