Add GitHub actions for testing VOL connectors (#3849)

* Fix issue with HDF5_VOL_ALLOW_EXTERNAL CMake variable

* Add initial API test workflow

* Initialize parallel testing with MPI_THREAD_MULTIPLE when testing API

* Add CMake variable to allow specifying a VOL connector's package name

* Remove call to MPI_Init in serial API tests

While previously necessary, it now interferes with VOL connectors that
may need to be initialized with MPI_THREAD_MULTIPLE

1 files changed, 36 insertions, 3 deletions

diff --git a/testpar/t_bigio.c b/testpar/t_bigio.c
index 910c7a2..068e3aa 100644
--- a/testpar/t_bigio.c
+++ b/testpar/t_bigio.c
@@ -1867,6 +1867,11 @@ main(int argc, char **argv)
     /* Set the bigio processing limit to be 'newsize' bytes */
     hsize_t oldsize   = H5_mpi_set_bigio_count(newsize);
     hid_t   acc_plist = H5I_INVALID_HID;
+#ifdef H5_HAVE_TEST_API
+    int required = MPI_THREAD_MULTIPLE;
+    int provided;
+#endif
+    int mpi_code;
 
     /* Having set the bigio handling to a size that is manageable,
      * we'll set our 'bigcount' variable to be 2X that limit so
@@ -1876,9 +1881,37 @@ main(int argc, char **argv)
     if (newsize != oldsize)
         bigcount = newsize * 2;
 
-    MPI_Init(&argc, &argv);
-    MPI_Comm_size(MPI_COMM_WORLD, &mpi_size_g);
-    MPI_Comm_rank(MPI_COMM_WORLD, &mpi_rank_g);
+#ifdef H5_HAVE_TEST_API
+    /* Attempt to initialize with MPI_THREAD_MULTIPLE if possible */
+    if (MPI_SUCCESS != (mpi_code = MPI_Init_thread(&argc, &argv, required, &provided))) {
+        printf("MPI_Init_thread failed with error code %d\n", mpi_code);
+        return -1;
+    }
+#else
+    if (MPI_SUCCESS != (mpi_code = MPI_Init(&argc, &argv))) {
+        printf("MPI_Init failed with error code %d\n", mpi_code);
+        return -1;
+    }
+#endif
+
+    if (MPI_SUCCESS != (mpi_code = MPI_Comm_rank(MPI_COMM_WORLD, &mpi_rank_g))) {
+        printf("MPI_Comm_rank failed with error code %d\n", mpi_code);
+        MPI_Finalize();
+        return -1;
+    }
+
+#ifdef H5_HAVE_TEST_API
+    /* Warn about missing MPI_THREAD_MULTIPLE support */
+    if ((provided < required) && MAIN_PROCESS)
+        printf("** MPI doesn't support MPI_Init_thread with MPI_THREAD_MULTIPLE **\n");
+#endif
+
+    if (MPI_SUCCESS != (mpi_code = MPI_Comm_size(MPI_COMM_WORLD, &mpi_size_g))) {
+        if (MAIN_PROCESS)
+            printf("MPI_Comm_size failed with error code %d\n", mpi_code);
+        MPI_Finalize();
+        return -1;
+    }
 
     /* Attempt to turn off atexit post processing so that in case errors
      * happen during the test and the process is aborted, it will not get