[svn-r706] Added must_convert parameter to sconv->read and sconv->write functions

so that reads/writes can proceed in the unoptimized way if necessary,
rather than simply failing if they can't be optimized.

3 files changed, 78 insertions, 24 deletions

diff --git a/src/H5D.c b/src/H5D.c
index 89526c8..5ad5145 100644
--- a/src/H5D.c
+++ b/src/H5D.c
@@ -1267,6 +1267,9 @@ H5D_close(H5D_t *dataset)
  * 	Robb Matzke, 11 Aug 1998
  *	Added timing calls around all the data space I/O functions.
  *
+ * 	rky 980918
+ *	Added must_convert to do non-optimized read when necessary.
+ *
  *-------------------------------------------------------------------------
  */
 herr_t
@@ -1294,6 +1297,7 @@ H5D_read(H5D_t *dataset, const H5T_t *mem_type, const H5S_t *mem_space,
     size_t		request_nelmts;		/*requested strip mine	*/
     H5T_bkg_t		need_bkg;		/*type of background buf*/
     H5S_t		*free_this_space=NULL;	/*data space to free	*/
+    hbool_t             must_convert;           /*have to xfer the slow way */
 #ifdef H5T_DEBUG
     H5_timer_t		timer;
 #endif
@@ -1390,13 +1394,19 @@ H5D_read(H5D_t *dataset, const H5T_t *mem_type, const H5S_t *mem_space,
 			       &(dataset->create_parms->efl),
 			       H5T_get_size (dataset->type), file_space,
 			       mem_space, xfer_parms->xfer_mode,
-			       buf/*out*/);
-        if (status>=0) goto succeed;
-#ifdef HAVE_PARALLEL
-	/* Supports only no conversion, type or space, for now. */
-	HGOTO_ERROR(H5E_DATASET, H5E_READERROR, FAIL,
-		    "optimized parallel read failed");
-#endif
+			       buf/*out*/, &must_convert );
+        if (status<0) {
+	    /* Supports only no conversion, type or space, for now. */
+	    HGOTO_ERROR(H5E_DATASET, H5E_READERROR, FAIL,
+		        "optimized read failed");
+	}
+	if (must_convert) {
+	    /* sconv->read cannot do a direct transfer;
+	     * fall through and xfer the data in the more roundabout way */
+	} else {
+	    /* direct xfer accomplished successfully */
+	    goto succeed;
+	}
 #ifdef H5D_DEBUG
 	if (H5DEBUG(D)) {
 	    fprintf (H5DEBUG(D), "H5D: data space conversion could not be "
@@ -1613,6 +1623,9 @@ H5D_read(H5D_t *dataset, const H5T_t *mem_type, const H5S_t *mem_space,
  * 	Robb Matzke, 9 Jun 1998
  *	The data space is no longer cached in the dataset struct.
  *
+ * 	rky 980918
+ *	Added must_convert to do non-optimized read when necessary.
+ *
  *-------------------------------------------------------------------------
  */
 herr_t
@@ -1639,6 +1652,7 @@ H5D_write(H5D_t *dataset, const H5T_t *mem_type, const H5S_t *mem_space,
     size_t		request_nelmts;		/*requested strip mine	*/
     H5T_bkg_t		need_bkg;		/*type of background buf*/
     H5S_t		*free_this_space=NULL;	/*data space to free	*/
+    hbool_t             must_convert;           /*have to xfer the slow way */
 #ifdef H5T_DEBUG
     H5_timer_t		timer;
 #endif
@@ -1742,13 +1756,20 @@ H5D_write(H5D_t *dataset, const H5T_t *mem_type, const H5S_t *mem_space,
 				&(dataset->create_parms->pline),
 				&(dataset->create_parms->efl),
 				H5T_get_size (dataset->type), file_space,
-				mem_space, xfer_parms->xfer_mode, buf);
-	if (status>=0) goto succeed;
-#ifdef HAVE_PARALLEL
-	/* Supports only no conversion, type or space, for now. */
-	HGOTO_ERROR(H5E_DATASET, H5E_WRITEERROR, FAIL,
-		    "optimized parallel write failed");
-#endif
+				mem_space, xfer_parms->xfer_mode, buf,
+				&must_convert /*out*/ );
+        if (status<0) {
+	    /* Supports only no conversion, type or space, for now. */
+	    HGOTO_ERROR(H5E_DATASET, H5E_READERROR, FAIL,
+		        "optimized write failed");
+	}
+	if (must_convert) {
+	    /* sconv->write cannot do a direct transfer;
+	     * fall through and xfer the data in the more roundabout way */
+	} else {
+	    /* direct xfer accomplished successfully */
+	    goto succeed;
+	}
 #ifdef H5D_DEBUG
 	if (H5DEBUG(D)) {
 	    fprintf (H5DEBUG(D), "H5D: data space conversion could not be "
diff --git a/src/H5Smpio.c b/src/H5Smpio.c
index 2275120..2610f94 100644
--- a/src/H5Smpio.c
+++ b/src/H5Smpio.c
@@ -55,6 +55,7 @@ H5S_mpio_spaces_xfer (H5F_t *f, const struct H5O_layout_t *layout,
                      const struct H5O_efl_t __unused__ *efl, size_t elmt_size,
                      const H5S_t *file_space, const H5S_t *mem_space,
                      const H5D_transfer_t xfer_mode, void *buf /*out*/,
+		     hbool_t *must_convert /*out*/,
 		     const hbool_t do_write );
 
 /*-------------------------------------------------------------------------
@@ -434,6 +435,9 @@ H5S_mpio_space_type( const H5S_t *space, const size_t elmt_size,
  *
  * Modifications:
  *
+ * rky 980918
+ * Added must_convert parameter to let caller know we can't optimize the xfer.
+ *
  *-------------------------------------------------------------------------
  */
 herr_t
@@ -442,6 +446,7 @@ H5S_mpio_spaces_xfer (H5F_t *f, const struct H5O_layout_t *layout,
                      const struct H5O_efl_t __unused__ *efl, size_t elmt_size,
                      const H5S_t *file_space, const H5S_t *mem_space,
                      const H5D_transfer_t xfer_mode, void *buf /*out*/,
+		     hbool_t *must_convert /*out*/,
 		     const hbool_t do_write )
 {
     herr_t	 ret_value = SUCCEED;
@@ -454,6 +459,8 @@ H5S_mpio_spaces_xfer (H5F_t *f, const struct H5O_layout_t *layout,
 
     FUNC_ENTER (H5S_mpio_spaces_xfer, FAIL);
 
+    *must_convert = 0;	/* means we at least tried to do optimized xfer */
+
     /* Check args */
     assert (f);
     assert (layout);
@@ -466,9 +473,11 @@ H5S_mpio_spaces_xfer (H5F_t *f, const struct H5O_layout_t *layout,
     /* Currently can only handle H5D_CONTIGUOUS layout */
     if (layout->type != H5D_CONTIGUOUS) {
 #ifdef H5S_DEBUG
-        fprintf (stderr, "H5S: can only create MPI datatype for hyperslab selection when layout is contiguous.\n" );
+	if (H5DEBUG(S)) {
+            fprintf (H5DEBUG(S), "H5S: can only create MPI datatype for hyperslab when layout is contiguous.\n" );
+	}
 #endif
-	ret_value = FAIL;
+	*must_convert = 1;      /* can't do optimized xfer; do the old way */
 	goto done;
     }
 
@@ -555,6 +564,9 @@ H5S_mpio_spaces_xfer (H5F_t *f, const struct H5O_layout_t *layout,
  *
  * Modifications:
  *
+ * rky 980918
+ * Added must_convert parameter to let caller know we can't optimize the xfer.
+ *
  *-------------------------------------------------------------------------
  */
 herr_t
@@ -562,7 +574,8 @@ H5S_mpio_spaces_read (H5F_t *f, const struct H5O_layout_t *layout,
                      const struct H5O_pline_t *pline,
                      const struct H5O_efl_t *efl, size_t elmt_size,
                      const H5S_t *file_space, const H5S_t *mem_space,
-                     const H5D_transfer_t xfer_mode, void *buf /*out*/ )
+                     const H5D_transfer_t xfer_mode, void *buf /*out*/,
+		     hbool_t *must_convert /*out*/ )
 {
     herr_t ret_value = FAIL;
 
@@ -570,7 +583,7 @@ H5S_mpio_spaces_read (H5F_t *f, const struct H5O_layout_t *layout,
 
     ret_value = H5S_mpio_spaces_xfer( f, layout, pline, efl, elmt_size,
 			file_space, mem_space, xfer_mode, (void*)buf,
-			0 /*read*/ );
+			must_convert /*out*/, 0 /*read*/ );
 
     FUNC_LEAVE (ret_value);
 } /* H5S_mpio_spaces_read() */
@@ -586,6 +599,9 @@ H5S_mpio_spaces_read (H5F_t *f, const struct H5O_layout_t *layout,
  *
  * Modifications:
  *
+ * rky 980918
+ * Added must_convert parameter to let caller know we can't optimize the xfer.
+ *
  *-------------------------------------------------------------------------
  */
 herr_t
@@ -593,7 +609,8 @@ H5S_mpio_spaces_write(H5F_t *f, const struct H5O_layout_t *layout,
                      const struct H5O_pline_t *pline,
                      const struct H5O_efl_t *efl, size_t elmt_size,
                      const H5S_t *file_space, const H5S_t *mem_space,
-                     const H5D_transfer_t xfer_mode, const void *buf )
+                     const H5D_transfer_t xfer_mode, const void *buf,
+		     hbool_t *must_convert /*out*/ )
 {
     herr_t ret_value = FAIL;
 
@@ -601,7 +618,7 @@ H5S_mpio_spaces_write(H5F_t *f, const struct H5O_layout_t *layout,
 
     ret_value = H5S_mpio_spaces_xfer( f, layout, pline, efl, elmt_size,
 			file_space, mem_space, xfer_mode, (void*)buf,
-			1 /*write*/ );
+			must_convert /*out*/, 1 /*write*/ );
 
     FUNC_LEAVE (ret_value);
 } /* H5S_mpio_spaces_write() */
diff --git a/src/H5Sprivate.h b/src/H5Sprivate.h
index c66f27d..862de9a 100644
--- a/src/H5Sprivate.h
+++ b/src/H5Sprivate.h
@@ -223,6 +223,17 @@ typedef struct H5S_conv_t {
      * If there is no data type conversion then it might be possible to
      * transfer data points between application memory and the file in one
      * step without going through the data type conversion buffer.
+     *
+     * rky 980918
+     * If the direct read or write function determines that the transfer
+     * must be done indirectly, i.e., through the conversion buffer or
+     * (in the case of parallel MPI-IO) in block-by-block transfers
+     * then the function returns with the value of must_convert!=0,
+     * the function's return value is SUCCEED,
+     * and no transfer of data is attempted.
+     * Otherwise the direct read or write function returns must_convert 0,
+     * with the function's return value being SUCCEED or FAIL
+     * depending on whether or not the transfer of data was successful.
      */
     
     /* Read from file to application w/o intermediate scratch buffer */
@@ -230,14 +241,17 @@ typedef struct H5S_conv_t {
 		   const struct H5O_pline_t *pline,
 		   const struct H5O_efl_t *efl, size_t elmt_size,
 		   const H5S_t *file_space, const H5S_t *mem_space,
-		   const H5D_transfer_t xfer_mode, void *buf/*out*/);
+		   const H5D_transfer_t xfer_mode, void *buf/*out*/,
+		   hbool_t *must_convert/*out*/ );
+
 
     /* Write directly from app buffer to file */
     herr_t (*write)(H5F_t *f, const struct H5O_layout_t *layout,
 		    const struct H5O_pline_t *pline,
 		    const struct H5O_efl_t *efl, size_t elmt_size,
 		    const H5S_t *file_space, const H5S_t *mem_space,
-		    const H5D_transfer_t xfer_mode, const void *buf);
+		    const H5D_transfer_t xfer_mode, const void *buf,
+		    hbool_t *must_convert/*out*/ );
     
 #ifdef H5S_DEBUG
     struct {
@@ -332,14 +346,16 @@ hbool_t H5S_hyper_select_valid (const H5S_t *space);
 		   const struct H5O_pline_t *pline,
 		   const struct H5O_efl_t *efl, size_t elmt_size,
 		   const H5S_t *file_space, const H5S_t *mem_space,
-		   const H5D_transfer_t xfer_mode, void *buf/*out*/);
+		   const H5D_transfer_t xfer_mode, void *buf/*out*/,
+                   hbool_t *must_convert /*out*/ );
 
     /* MPI-IO function to write directly from app buffer to file rky980813 */
     herr_t H5S_mpio_spaces_write(H5F_t *f, const struct H5O_layout_t *layout,
 		    const struct H5O_pline_t *pline,
 		    const struct H5O_efl_t *efl, size_t elmt_size,
 		    const H5S_t *file_space, const H5S_t *mem_space,
-		    const H5D_transfer_t xfer_mode, const void *buf);
+		    const H5D_transfer_t xfer_mode, const void *buf,
+                    hbool_t *must_convert /*out*/ );
 
 #ifndef _H5S_IN_H5S_C
     /* Global var whose value comes from environment variable */