src/h5core/private/h5_init.{c,h}

- initialize MPI if not yet done

src/h5core/private/h5_init.c

@@ -666,11 +666,17 @@ h5_err_t
 h5priv_initialize (
         void
         ) {
-	h5_initialized = 1;
 	memset (&h5_call_stack, 0, sizeof (h5_call_stack));
+	// must be set here, otherwise next statement will fail!
+	h5_initialized = 1;
 	H5_CORE_API_ENTER (h5_err_t, "%s", "void");
 	ret_value = H5_SUCCESS;
 #ifdef PARALLEL_IO
+	int mpi_is_initialized;
+	MPI_Initialized (&mpi_is_initialized);
+	if (!mpi_is_initialized) {
+		MPI_Init (NULL, NULL);
+	}
 	if (h5priv_mpi_comm_rank (MPI_COMM_WORLD, &h5_myproc) < 0) {
 		exit (42);
 	}

src/h5core/private/h5_init.h

@@ -19,6 +19,7 @@
 #if !defined (PARALLEL_IO)
 typedef int MPI_Comm;
 #define MPI_Init(argc, argv)
+#define MPI_Initialized () (1)
 #define MPI_Comm_size(comm, nprocs) {(void)comm; *nprocs = 1; }
 #define MPI_Comm_rank(comm, myproc) {(void)comm; *myproc = 0; }
 #define MPI_Finalize()