[svn-r596] Added conversion to MPI datatypes.

1 files changed, 210 insertions, 52 deletions

diff --git a/src/H5Fmpio.c b/src/H5Fmpio.c
index f71b653..7647031 100644
--- a/src/H5Fmpio.c
+++ b/src/H5Fmpio.c
@@ -99,10 +99,10 @@ static H5F_low_t *H5F_mpio_open(const char *name,
 				const H5F_access_t *access_parms, uintn flags,
 				H5F_search_t *key/*out*/);
 static herr_t H5F_mpio_close(H5F_low_t *lf, const H5F_access_t *access_parms);
-static herr_t H5F_mpio_read(H5F_low_t *lf, const H5F_access_t *access_parms,
+static herr_t H5F_mpio_read(H5F_low_t *lf, H5F_access_t *access_parms,
 			    const H5D_transfer_t xfer_mode,
 			    const haddr_t *addr, size_t size, uint8 *buf/*out*/);
-static herr_t H5F_mpio_write(H5F_low_t *lf, const H5F_access_t *access_parms,
+static herr_t H5F_mpio_write(H5F_low_t *lf, H5F_access_t *access_parms,
 			     const H5D_transfer_t xfer_mode,
 			     const haddr_t *addr, size_t size, const uint8 *buf);
 static herr_t H5F_mpio_flush(H5F_low_t *lf, const H5F_access_t *access_parms);
@@ -113,8 +113,21 @@ const H5F_low_class_t	H5F_LOW_MPIO_g[1] = {{
     H5F_mpio_access,		/*access method				*/
     H5F_mpio_open,		/*open method				*/
     H5F_mpio_close,		/*close method				*/
+
+    /* rky 980816
+     * this is ugly, but removing the const modifier from access_parms
+     * in the parameter list of the write function in H5F_low_class_t
+     * would propagate to a lot of functions that don't change that param */
+    (int(*)(struct H5F_low_t *lf, const H5F_access_t *access_parms, const H5D_transfer_t xfer_mode, const haddr_t *addr, size_t size, uint8 *buf))
     H5F_mpio_read,		/*read method				*/
+
+    /* rky 980816
+     * this is ugly, but removing the const modifier from access_parms
+     * in the parameter list of the write function in H5F_low_class_t
+     * would propagate to a lot of functions that don't change that param */
+    (int(*)(struct H5F_low_t *lf, const H5F_access_t *access_parms, const H5D_transfer_t xfer_mode, const haddr_t *addr, size_t size, const uint8 *buf))
     H5F_mpio_write,		/*write method				*/
+
     H5F_mpio_flush,		/*flush method				*/
     NULL,			/*extend method				*/
     NULL,			/*alloc method				*/
@@ -207,9 +220,9 @@ H5F_mpio_access(const char *name, const H5F_access_t *access_parms, int mode,
     /* (char*) name is okay since MPI_File_open will not change it. */
     mpierr = MPI_File_open(access_parms->u.mpio.comm, (char*) name,
 			   mpi_mode, access_parms->u.mpio.info, &fh );
-    if (mpierr == MPI_SUCCESS) {
+    if (MPI_SUCCESS == mpierr) {
 	mpierr = MPI_File_close( &fh );
-	if (mpierr != MPI_SUCCESS)
+	if (MPI_SUCCESS != mpierr)
 	    HRETURN_ERROR(H5E_IO, H5E_MPI, FAIL, "MPI_File_close failed");
 	ret_val = TRUE;
     } else if (mode == F_OK) {
@@ -217,9 +230,9 @@ H5F_mpio_access(const char *name, const H5F_access_t *access_parms, int mode,
 	mpierr = MPI_File_open(access_parms->u.mpio.comm, (char*)name,
 			       MPI_MODE_WRONLY, access_parms->u.mpio.info,
 			       &fh );
-	if (mpierr == MPI_SUCCESS) {
+	if (MPI_SUCCESS == mpierr) {
 	    mpierr = MPI_File_close( &fh );
-	    if (mpierr != MPI_SUCCESS)
+	    if (MPI_SUCCESS != mpierr)
 		HRETURN_ERROR(H5E_IO, H5E_MPI, FAIL, "MPI_File_close failed");
 	    ret_val = TRUE;
 	}
@@ -317,7 +330,7 @@ H5F_mpio_open(const char *name, const H5F_access_t *access_parms, uintn flags,
 #endif
 
     mpierr = MPI_File_open(access_parms->u.mpio.comm, (char*)name, mpi_amode, access_parms->u.mpio.info, &fh);
-    if (mpierr != MPI_SUCCESS) {
+    if (MPI_SUCCESS != mpierr) {
         MPI_Error_string( mpierr, mpierrmsg, &msglen );
 	HRETURN_ERROR(H5E_IO, H5E_CANTOPENFILE, NULL, mpierrmsg );
     }
@@ -325,7 +338,7 @@ H5F_mpio_open(const char *name, const H5F_access_t *access_parms, uintn flags,
     /* truncate the file, if requested */
     if (flags&H5F_ACC_TRUNC) {
 	mpierr = MPI_File_set_size( fh, (MPI_Offset)0 );
-	if (mpierr != MPI_SUCCESS) {
+	if (MPI_SUCCESS != mpierr) {
 	    MPI_File_close( &fh );
 	    HRETURN_ERROR(H5E_IO, H5E_CANTOPENFILE, NULL,
 			  "MPI_File_set_size failed trying to truncate file" );
@@ -340,7 +353,7 @@ H5F_mpio_open(const char *name, const H5F_access_t *access_parms, uintn flags,
     lf->u.mpio.f = fh;
     H5F_addr_reset(&(lf->eof));
     mpierr = MPI_File_get_size( fh, &size );
-    if (mpierr != MPI_SUCCESS) {
+    if (MPI_SUCCESS != mpierr) {
 	MPI_File_close( &(lf->u.mpio.f) );
         MPI_Error_string( mpierr, mpierrmsg, &msglen );
 	HRETURN_ERROR(H5E_IO, H5E_CANTOPENFILE, NULL, mpierrmsg );
@@ -411,7 +424,7 @@ H5F_mpio_close(H5F_low_t *lf, const H5F_access_t __unused__ *access_parms)
     mpierr = MPI_File_close( &(lf->u.mpio.f) );
     /* MPI_File_close sets lf->u.mpio.f to MPI_FILE_NULL */
 
-    if (mpierr != MPI_SUCCESS) {
+    if (MPI_SUCCESS != mpierr) {
         MPI_Error_string( mpierr, mpierrmsg, &msglen );
 	HRETURN_ERROR(H5E_IO, H5E_CLOSEERROR, FAIL, mpierrmsg );
     }
@@ -426,20 +439,28 @@ H5F_mpio_close(H5F_low_t *lf, const H5F_access_t __unused__ *access_parms)
 /*-------------------------------------------------------------------------
  * Function:    H5F_mpio_read
  *
- * Purpose:     Reads SIZE bytes beginning at address ADDR in file LF and
- *              places them in buffer BUF.  Reading past the logical or
- *              physical end of file returns zeros instead of failing.
+ * Purpose:     Depending on a field in access params, either:
+ *		- Writes SIZE bytes from the beginning of BUF into file LF
+ *                at file address ADDR.
+ *		- Reads SIZE bytes beginning at address ADDR in file LF
+ *                and places them in buffer BUF.
+ *		- Uses the (potentially complex) file and buffer types
+ *                to effect the transfer.
+ *		  This can allow MPI to coalesce requests from
+ *		  different processes (collective or independent).
+ *
+ *              Reading past the end of the MPI file
+ *		returns zeros instead of failing.
  *
  * Errors:
  *              IO        READERROR     MPI_File_read_at failed. 
  *              IO        READERROR     MPI_Get_count failed
  *
  * Return:      Success:        SUCCEED
- *
  *              Failure:        FAIL
+ *		(use_types and old_use_types in the access params are altered)
  *
- * Programmer:  
- *              January 30, 1998
+ * Programmer:  rky 980130
  *
  * Modifications:
  *
@@ -452,19 +473,24 @@ H5F_mpio_close(H5F_low_t *lf, const H5F_access_t __unused__ *access_parms)
  * 	Albert Cheng, June 1, 1998
  *	Added xfer_mode to control independent or collective MPI read.
  *
+ * 	rky 980816
+ *	Use btype, ftype, and disp from access parms.
+ *	The guts of H5F_mpio_read and H5F_mpio_write
+ *	should be replaced by a single dual-purpose routine.
+ *
  *-------------------------------------------------------------------------
  */
 static herr_t
-H5F_mpio_read(H5F_low_t *lf, const H5F_access_t __unused__ *access_parms,
+H5F_mpio_read(H5F_low_t *lf, H5F_access_t *access_parms,
 	      const H5D_transfer_t xfer_mode,
 	      const haddr_t *addr, size_t size, uint8 *buf/*out*/)
 {
-    MPI_Offset              mpi_off;
-    int                     size_i, bytes_read, n;
-    MPI_Status              mpi_stat;
-    int                     mpierr;
-    char                    mpierrmsg[MPI_MAX_ERROR_STRING];
-    int                     msglen;
+    MPI_Offset  mpi_off, mpi_disp;
+    MPI_Status  mpi_stat;
+    MPI_Datatype buf_type, file_type;
+    int         mpierr, msglen, size_i, bytes_read, n;
+    int		use_types_this_time, used_types_last_time;
+    char        mpierrmsg[MPI_MAX_ERROR_STRING];
 
     FUNC_ENTER(H5F_mpio_read, FAIL);
 #ifdef H5Fmpio_DEBUG
@@ -472,14 +498,14 @@ H5F_mpio_read(H5F_low_t *lf, const H5F_access_t __unused__ *access_parms,
     	fprintf(stdout, "Entering H5F_mpio_read\n" );
 #endif
 
-    /* numeric conversion of offset and size  */
+    /* some numeric conversions */
     if (SUCCEED != H5F_haddr_to_MPIOff( *addr, &mpi_off )) {
-	HRETURN_ERROR(H5E_IO, H5E_READERROR, FAIL,
+	HRETURN_ERROR(H5E_IO, H5E_BADTYPE, FAIL,
 			"couldn't convert addr to MPIOffset" );
     }
     size_i = (int)size;
     if (size_i != size) {	/* check type conversion */
-	HRETURN_ERROR(H5E_IO, H5E_READERROR, FAIL,
+	HRETURN_ERROR(H5E_IO, H5E_BADTYPE, FAIL,
 			"couldn't convert size to int" );
     }
 
@@ -489,12 +515,53 @@ H5F_mpio_read(H5F_low_t *lf, const H5F_access_t __unused__ *access_parms,
                 mpi_off, size_i );
 #endif
 
+    /* Set up for a fancy xfer using complex types, or single byte block.
+     * We wouldn't need to rely on the use_types field
+     * if MPI semantics allowed us to test that btype=ftype=MPI_BYTE
+     * (or even MPI_TYPE_NULL, which could mean "use MPI_BYTE" by convention).
+     */
+    use_types_this_time = access_parms->u.mpio.use_types;
+    if (access_parms->u.mpio.use_types) {
+	/* prepare for a full-blown xfer using btype, ftype, and disp */
+	buf_type = access_parms->u.mpio.btype;
+	file_type = access_parms->u.mpio.ftype;
+	if (SUCCEED !=
+	    H5F_haddr_to_MPIOff( access_parms->u.mpio.disp, &mpi_disp)) {
+	    HRETURN_ERROR(H5E_IO, H5E_BADTYPE, FAIL, "couldn't convert addr to MPIOffset" );
+	}
+    } else {
+	/* Prepare for a simple xfer of a contiguous block of bytes.
+	 * The btype, ftype, and disp fields are not used. */
+	buf_type = MPI_BYTE;
+	file_type = MPI_BYTE;
+	mpi_disp = 0;		/* mpi_off is sufficient */
+    }
+
+    /* Don't bother to reset the view if we're not using the types this time,
+     * and did we didn't use them last time either. */
+    used_types_last_time = access_parms->u.mpio.old_use_types;
+    if (used_types_last_time	/* change to new ftype or MPI_BYTE */
+    ||  use_types_this_time) 	/* almost certainly a different ftype */ {
+	mpierr = MPI_File_set_view( lf->u.mpio.f, mpi_disp,
+				    MPI_BYTE, file_type,
+				    "native",  access_parms->u.mpio.info );
+	if (MPI_SUCCESS != mpierr) {
+	    MPI_Error_string( mpierr, mpierrmsg, &msglen );
+	    HRETURN_ERROR(H5E_IO, H5E_MPI, FAIL, mpierrmsg );
+	}
+    }
+    /* We always set the use_types flag to 0 because the 
+     * default is not to use types next time,
+     * unless someone explicitly requests it by setting this flag to !=0. */
+    access_parms->u.mpio.old_use_types = use_types_this_time;
+    access_parms->u.mpio.use_types = 0;
+
     /* Read the data.  */
     switch (xfer_mode){
     case H5D_XFER_INDEPENDENT:
     case H5D_XFER_DFLT:
 	mpierr = MPI_File_read_at     ( lf->u.mpio.f, mpi_off, (void*) buf,
-					size_i, MPI_BYTE, &mpi_stat );
+					size_i, buf_type, &mpi_stat );
 	break;
 	
     case H5D_XFER_COLLECTIVE:
@@ -502,13 +569,13 @@ H5F_mpio_read(H5F_low_t *lf, const H5F_access_t __unused__ *access_parms,
 	printf("%s: using MPIO collective mode\n", FUNC);
 #endif
 	mpierr = MPI_File_read_at_all ( lf->u.mpio.f, mpi_off, (void*) buf,
-					size_i, MPI_BYTE, &mpi_stat );
+					size_i, buf_type, &mpi_stat );
 	break;
 
     default:
 	HRETURN_ERROR(H5E_IO, H5E_BADVALUE, FAIL, "invalid file access mode");
     }
-    if (mpierr != MPI_SUCCESS) {
+    if (MPI_SUCCESS != mpierr) {
         MPI_Error_string( mpierr, mpierrmsg, &msglen );
 	HRETURN_ERROR(H5E_IO, H5E_READERROR, FAIL, mpierrmsg );
     }
@@ -521,9 +588,9 @@ H5F_mpio_read(H5F_low_t *lf, const H5F_access_t __unused__ *access_parms,
 	    "In H5F_mpio_read after Get_count size_i=%d bytes_read=%d\n",
 	    size_i, bytes_read );
 #endif
-    if (mpierr != MPI_SUCCESS) {
+    if (MPI_SUCCESS != mpierr) {
         MPI_Error_string( mpierr, mpierrmsg, &msglen );
-	HRETURN_ERROR(H5E_IO, H5E_READERROR, FAIL, mpierrmsg );
+	HRETURN_ERROR(H5E_IO, H5E_MPI, FAIL, mpierrmsg );
     }
 
 #define MPI_KLUGE0202
@@ -538,9 +605,18 @@ H5F_mpio_read(H5F_low_t *lf, const H5F_access_t __unused__ *access_parms,
 			"MPI_Get_count returned invalid count" );
     }
 
-    /* read zeroes past the end of the file */
-    if ((n=(size_i-bytes_read)) > 0) {
-        HDmemset( buf+bytes_read, 0, (size_t)n );
+    /* beyond end of file, pretend we're reading zeroes */
+    if (use_types_this_time) {
+	/* BUG rky 980816  Not implemented yet.  How to do it??? */
+	HRETURN_ERROR(H5E_IO, H5E_UNSUPPORTED, FAIL,
+		"haven't implemented reading zeroes beyond end of file" );
+    } else {
+	/* BUG??? rky 980816
+	 * This gives us zeroes beyond end of physical MPI file.
+	 * What about reading past logical end of HDF5 file??? */
+	if ((n=(size_i-bytes_read)) > 0) {
+	    HDmemset( buf+bytes_read, 0, (size_t)n );
+	}
     }
 
 #ifdef H5Fmpio_DEBUG
@@ -548,20 +624,25 @@ H5F_mpio_read(H5F_low_t *lf, const H5F_access_t __unused__ *access_parms,
     	fprintf(stdout, "Leaving H5F_mpio_read\n" );
 #endif
     FUNC_LEAVE(SUCCEED);
-}
+} /* H5F_mpio_read */
 
 /*-------------------------------------------------------------------------
  * Function:    H5F_mpio_write
  *
- * Purpose:     Writes SIZE bytes from the beginning of BUF into file LF at
- *              file address ADDR.
+ * Purpose:     Depending on a field in access params, either:
+ *		- Writes SIZE bytes from the beginning of BUF into file LF
+ *                at file address ADDR.
+ *		- Uses the (potentially complex) file and buffer types
+ *                to effect the transfer.
+ *		  This can allow MPI to coalesce requests from
+ *		  different processes (collective or independent).
  *
  * Errors:
  *              IO        WRITEERROR    MPI_File_write_at failed. 
  *
  * Return:      Success:        SUCCEED
- *
  *              Failure:        FAIL
+ *		(use_types and old_use_types in the access params are altered)
  *
  * Programmer:  
  *              January 30, 1998
@@ -580,17 +661,24 @@ H5F_mpio_read(H5F_low_t *lf, const H5F_access_t __unused__ *access_parms,
  * 	Albert Cheng, June 1, 1998
  *	Added xfer_mode to control independent or collective MPI write.
  *
+ * 	rky 980816
+ *	Use btype, ftype, and disp from access parms.
+ *	The guts of H5F_mpio_read and H5F_mpio_write
+ *	should be replaced by a single dual-purpose routine.
+ *
  *-------------------------------------------------------------------------
  */
 static herr_t
-H5F_mpio_write(H5F_low_t *lf, const H5F_access_t __unused__ *access_parms,
+H5F_mpio_write(H5F_low_t *lf, H5F_access_t *access_parms,
 	       const H5D_transfer_t xfer_mode,
 	       const haddr_t *addr, size_t size, const uint8 *buf)
 {
-    MPI_Offset              mpi_off;
-    MPI_Status              mpi_stat;
-    int                     mpierr, msglen, size_i;
-    char                    mpierrmsg[MPI_MAX_ERROR_STRING];
+    MPI_Offset  mpi_off, mpi_disp;
+    MPI_Status  mpi_stat;
+    MPI_Datatype buf_type, file_type;
+    int         mpierr, msglen, size_i, bytes_written;
+    int		use_types_this_time, used_types_last_time;
+    char        mpierrmsg[MPI_MAX_ERROR_STRING];
 
     FUNC_ENTER(H5F_mpio_write, FAIL);
 #ifdef H5Fmpio_DEBUG
@@ -598,14 +686,18 @@ H5F_mpio_write(H5F_low_t *lf, const H5F_access_t __unused__ *access_parms,
     	fprintf(stdout, "Entering H5F_mpio_write\n" );
 #endif
 
-    /* numeric conversion of offset and size  */
+    /* some numeric conversions */
     if (SUCCEED != H5F_haddr_to_MPIOff( *addr, &mpi_off )) {
-	HRETURN_ERROR(H5E_IO, H5E_READERROR, FAIL,
+	HRETURN_ERROR(H5E_IO, H5E_BADTYPE, FAIL,
+			"couldn't convert addr to MPIOffset" );
+    }
+    if (SUCCEED!=H5F_haddr_to_MPIOff( access_parms->u.mpio.disp, &mpi_disp)) {
+	HRETURN_ERROR(H5E_IO, H5E_BADTYPE, FAIL,
 			"couldn't convert addr to MPIOffset" );
     }
     size_i = (int)size;
     if (size_i != size) {	/* check type conversion */
-	HRETURN_ERROR(H5E_IO, H5E_READERROR, FAIL,
+	HRETURN_ERROR(H5E_IO, H5E_BADTYPE, FAIL,
 			"couldn't convert size to int" );
     }
 
@@ -615,12 +707,53 @@ H5F_mpio_write(H5F_low_t *lf, const H5F_access_t __unused__ *access_parms,
                 mpi_off, size_i );
 #endif
 
+    /* Set up for a fancy xfer using complex types, or single byte block.
+     * We wouldn't need to rely on the use_types field
+     * if MPI semantics allowed us to test that btype=ftype=MPI_BYTE
+     * (or even MPI_TYPE_NULL, which could mean "use MPI_BYTE" by convention).
+     */
+    use_types_this_time = access_parms->u.mpio.use_types;
+    if (use_types_this_time) {
+	/* prepare for a full-blown xfer using btype, ftype, and disp */
+	buf_type = access_parms->u.mpio.btype;
+	file_type = access_parms->u.mpio.ftype;
+	if (SUCCEED !=
+	    H5F_haddr_to_MPIOff( access_parms->u.mpio.disp, &mpi_disp)) {
+	    HRETURN_ERROR(H5E_IO, H5E_BADTYPE, FAIL, "couldn't convert addr to MPIOffset" );
+	}
+    } else {
+	/* Prepare for a simple xfer of a contiguous block of bytes.
+	 * The btype, ftype, and disp fields are not used. */
+	buf_type = MPI_BYTE;
+	file_type = MPI_BYTE;
+	mpi_disp = 0;		/* mpi_off is sufficient */
+    }
+
+    /* Don't bother to reset the view if we're not using the types this time,
+     * and did we didn't use them last time either. */
+    used_types_last_time = access_parms->u.mpio.old_use_types;
+    if (used_types_last_time	/* change to new ftype or MPI_BYTE */
+    ||  use_types_this_time) 	/* almost certainly a different ftype */ {
+	mpierr = MPI_File_set_view( lf->u.mpio.f, mpi_disp,
+				    MPI_BYTE, file_type,
+				    "native",  access_parms->u.mpio.info );
+	if (MPI_SUCCESS != mpierr) {
+	    MPI_Error_string( mpierr, mpierrmsg, &msglen );
+	    HRETURN_ERROR(H5E_IO, H5E_MPI, FAIL, mpierrmsg );
+	}
+    }
+    /* We always set the use_types flag to 0 because the 
+     * default is not to use types next time,
+     * unless someone explicitly requests it by setting this flag to !=0. */
+    access_parms->u.mpio.old_use_types = use_types_this_time;
+    access_parms->u.mpio.use_types = 0;
+
     /* Write the data.  */
     switch (xfer_mode){
     case H5D_XFER_INDEPENDENT:
     case H5D_XFER_DFLT:
 	mpierr = MPI_File_write_at    ( lf->u.mpio.f, mpi_off, (void*) buf,
-					size_i, MPI_BYTE, &mpi_stat );
+					size_i, buf_type, &mpi_stat );
 	break;
 	
     case H5D_XFER_COLLECTIVE:
@@ -628,15 +761,40 @@ H5F_mpio_write(H5F_low_t *lf, const H5F_access_t __unused__ *access_parms,
 	printf("%s: using MPIO collective mode\n", FUNC);
 #endif
 	mpierr = MPI_File_write_at_all( lf->u.mpio.f, mpi_off, (void*) buf,
-					size_i, MPI_BYTE, &mpi_stat );
+					size_i, buf_type, &mpi_stat );
 	break;
 
     default:
 	HRETURN_ERROR(H5E_IO, H5E_BADVALUE, FAIL, "invalid file access mode");
     }
-    if (mpierr != MPI_SUCCESS) {
+    if (MPI_SUCCESS != mpierr) {
         MPI_Error_string( mpierr, mpierrmsg, &msglen );
-	HRETURN_ERROR(H5E_IO, H5E_READERROR, FAIL, mpierrmsg );
+	HRETURN_ERROR(H5E_IO, H5E_WRITEERROR, FAIL, mpierrmsg );
+    }
+
+    /* How many bytes were actually written? */
+    mpierr = MPI_Get_count( &mpi_stat, MPI_BYTE, &bytes_written );
+#ifdef H5Fmpio_DEBUG
+    if (H5F_mpio_Debug[(int)'c'])
+    	fprintf(stdout,
+	    "In H5F_mpio_write after Get_count size_i=%d bytes_written=%d\n",
+	    size_i, bytes_written );
+#endif
+    if (MPI_SUCCESS != mpierr) {
+        MPI_Error_string( mpierr, mpierrmsg, &msglen );
+	HRETURN_ERROR(H5E_IO, H5E_MPI, FAIL, mpierrmsg );
+    }
+
+#define MPI_KLUGE0202
+#ifdef MPI_KLUGE0202
+    /* KLUGE rky 980202 MPI_Get_count incorrectly returns negative count;
+       fake a complete write */
+    bytes_written = size_i;	/* KLUGE rky 980202 */
+#endif
+
+    if ((bytes_written<0) || (bytes_written > size_i)) {
+	HRETURN_ERROR(H5E_IO, H5E_WRITEERROR, FAIL,
+			"MPI_Get_count returned invalid count" );
     }
 
 #ifdef H5Fmpio_DEBUG
@@ -644,7 +802,7 @@ H5F_mpio_write(H5F_low_t *lf, const H5F_access_t __unused__ *access_parms,
     	fprintf(stdout, "Leaving H5F_mpio_write\n" );
 #endif
     FUNC_LEAVE(SUCCEED);
-}
+} /* H5F_mpio_write */
 
 /*-------------------------------------------------------------------------
  * Function:    H5F_mpio_flush
@@ -682,7 +840,7 @@ H5F_mpio_flush(H5F_low_t *lf, const H5F_access_t __unused__ *access_parms)
 #endif
 
     mpierr = MPI_File_sync( lf->u.mpio.f );
-    if (mpierr != MPI_SUCCESS) {
+    if (MPI_SUCCESS != mpierr) {
         MPI_Error_string( mpierr, mpierrmsg, &msglen );
 	HRETURN_ERROR(H5E_IO, H5E_WRITEERROR, FAIL, mpierrmsg );
     }