[svn-r161] Changes since 19980121

----------------------

./MANIFEST
./src/H5Psimp.c		[NEW]
./src/Makefile.in
	Added H5Psimp.c and populated it with some conversion
	functions. Eventually the parts of H5P.c that operate on
	simple data spaces will be migrated to H5Psimp.c and other
	files will be created for other types of data spaces.

./src/H5D.c
	The read pipeline, H5Dread(), has been updated to handle data
	space conversion although the actual simple data space
	conversion functions don't do anything yet. But we're getting
	really close!

./src/H5P.c
./src/H5Pprivate.h
	Added H5P_find() to locate data space conversion functions.
	Added typedefs for structs related to data space conversion.

5 files changed, 184 insertions, 83 deletions

diff --git a/MANIFEST b/MANIFEST
index f381227..4b5dda3 100644
--- a/MANIFEST
+++ b/MANIFEST
@@ -90,6 +90,7 @@
 ./src/H5P.c
 ./src/H5Pprivate.h
 ./src/H5Ppublic.h
+./src/H5Psimp.c
 ./src/H5private.h
 ./src/H5public.h
 ./src/H5T.c
diff --git a/src/H5D.c b/src/H5D.c
index dea5d3e..869e79f 100644
--- a/src/H5D.c
+++ b/src/H5D.c
@@ -824,14 +824,12 @@ H5D_read(H5D_t *dataset, const H5T_t *mem_type, const H5P_t *mem_space,
 	 void *buf/*out*/)
 {
     size_t		nelmts, src_size, dst_size;
-    size_t		offset[H5O_LAYOUT_NDIMS];
-    size_t		size[H5O_LAYOUT_NDIMS];
-    size_t		zero[H5O_LAYOUT_NDIMS];
-    intn		i;
     herr_t		ret_value = FAIL;
-    uint8		*conv_buf = NULL;	/*data type conv buffer	*/
-    H5T_conv_t		conv_func = NULL;	/*conversion function	*/
+    uint8		*tconv_buf = NULL;	/*data type conv buffer	*/
+    H5T_conv_t		tconv_func = NULL;	/*conversion function	*/
     hid_t		src_id = -1, dst_id = -1;/*temporary type atoms */
+    const H5P_conv_t	*sconv_func = NULL;	/*space conversion funcs*/
+    H5P_number_t	numbering;		/*element numbering info*/
 
     FUNC_ENTER(H5D_read, FAIL);
 
@@ -840,13 +838,8 @@ H5D_read(H5D_t *dataset, const H5T_t *mem_type, const H5P_t *mem_space,
     assert(mem_type);
     assert(xfer_parms);
     assert(buf);
-
-    if ((mem_space && H5P_cmp(mem_space, dataset->space)) ||
-	(file_space && H5P_cmp(file_space, dataset->space))) {
-	HGOTO_ERROR(H5E_DATASET, H5E_UNSUPPORTED, FAIL,
-		    "space conversion not supported yet");
-    }
-    assert (!mem_space || H5P_SIMPLE==mem_space->type);
+    if (!file_space) file_space = dataset->space;
+    if (!mem_space) mem_space = file_space;
     
     /*
      * Convert data types to atoms because the conversion functions are
@@ -859,6 +852,27 @@ H5D_read(H5D_t *dataset, const H5T_t *mem_type, const H5P_t *mem_space,
     }
 
     /*
+     * Locate the type conversion function, data space conversion, and set up
+     * the element numbering information.
+     */
+    if (NULL == (tconv_func = H5T_find(dataset->type, mem_type))) {
+	HGOTO_ERROR(H5E_DATASET, H5E_UNSUPPORTED, FAIL,
+		    "unable to convert between src and dest data types");
+    }
+    if (NULL==(sconv_func=H5P_find (file_space, mem_space))) {
+	HGOTO_ERROR (H5E_DATASET, H5E_UNSUPPORTED, FAIL,
+		     "unable to convert between src and dest data spaces");
+    }
+    if (sconv_func->init &&
+	(sconv_func->init)(&(dataset->layout), mem_space, file_space,
+			   &numbering/*out*/)<=0) {
+	HGOTO_ERROR (H5E_DATASET, H5E_CANTINIT, FAIL,
+		     "unable to initialize element numbering information");
+    } else {
+	HDmemset (&numbering, 0, sizeof numbering);
+    }
+    
+    /*
      * Compute the size of the request and allocate scratch buffers.
      */
 #ifndef LATER
@@ -869,62 +883,43 @@ H5D_read(H5D_t *dataset, const H5T_t *mem_type, const H5P_t *mem_space,
     nelmts = H5P_get_npoints(dataset->space);
     src_size = nelmts * H5T_get_size(dataset->type);
     dst_size = nelmts * H5T_get_size(mem_type);
-    conv_buf = H5MM_xmalloc(MAX(src_size, dst_size));
+    tconv_buf = H5MM_xmalloc(MAX(src_size, dst_size));
 #endif
 
     /*
-     * Locate the type conversion function.
-     */
-    if (NULL == (conv_func = H5T_find(dataset->type, mem_type))) {
-	HGOTO_ERROR(H5E_DATASET, H5E_UNSUPPORTED, FAIL,
-		    "unable to convert between src and dest data types");
-    }
-
-    /*
      * Gather the data from disk into the data type conversion buffer.
      */
-#ifndef LATER
-    /*
-     * Note: We only support complete reads currently.  That is, the
-     *	     hyperslab must begin at zero in memory and on disk and the
-     *	     size of the hyperslab must be the same as the array on disk.
-     */
-    for (i = 0; i < dataset->layout.ndims; i++) {
-	zero[i] = 0;
-	offset[i] = 0;
-    }
-    i = H5P_get_dims (dataset->space, size);
-    assert (i+1==dataset->layout.ndims);
-    size[i] = H5T_get_size (dataset->type);
-#endif
-    if (H5F_arr_read(dataset->ent.file, &(dataset->layout), size, offset,
-		     zero, size, conv_buf) < 0) {
-	HGOTO_ERROR(H5E_IO, H5E_READERROR, FAIL, "read failed");
+    if ((sconv_func->fgath)(dataset->ent.file, &(dataset->layout),
+			    H5T_get_size (dataset->type), file_space,
+			    &numbering, 0, nelmts,
+			    tconv_buf/*out*/)<0) {
+	HGOTO_ERROR(H5E_IO, H5E_READERROR, FAIL, "gather failed");
     }
 
     /*
      * Perform data type conversion.
      */
-    if ((conv_func) (src_id, dst_id, nelmts, conv_buf, NULL) < 0) {
+    if ((tconv_func) (src_id, dst_id, nelmts, tconv_buf, NULL) < 0) {
 	HGOTO_ERROR(H5E_DATASET, H5E_CANTINIT, FAIL,
 		    "data type conversion failed");
     }
 
     /*
-     * Copy conversion buffer into destination.
+     * Scatter the data into memory.
      */
-    HDmemcpy(buf, conv_buf, dst_size);
-
+    if ((sconv_func->mscat)(tconv_buf, H5T_get_size (mem_type), mem_space,
+			    &numbering, 0, nelmts, buf/*out*/)<0) {
+	HGOTO_ERROR (H5E_IO, H5E_WRITEERROR, FAIL, "scatter failed");
+    }
     ret_value = SUCCEED;
+    
   done:
-    if (src_id >= 0)
-	H5A_dec_ref(src_id);
-    if (dst_id >= 0)
-	H5A_dec_ref(dst_id);
-    conv_buf = H5MM_xfree(conv_buf);
+    if (src_id >= 0) H5A_dec_ref(src_id);
+    if (dst_id >= 0) H5A_dec_ref(dst_id);
+    tconv_buf = H5MM_xfree(tconv_buf);
     FUNC_LEAVE(ret_value);
 }
-
+
 /*-------------------------------------------------------------------------
  * Function:	H5D_write
  *
@@ -953,8 +948,8 @@ H5D_write(H5D_t *dataset, const H5T_t *mem_type, const H5P_t *mem_space,
     size_t	zero[H5O_LAYOUT_NDIMS];
     intn	i;
     herr_t	ret_value = FAIL;
-    uint8	*conv_buf = NULL;	/*data type conversion buffer	*/
-    H5T_conv_t	conv_func = NULL;	/*data type conversion function */
+    uint8	*tconv_buf = NULL;	/*data type conversion buffer	*/
+    H5T_conv_t	tconv_func = NULL;	/*data type conversion function */
     hid_t	src_id = -1, dst_id = -1; /*temporary type atoms	*/
 
     FUNC_ENTER(H5D_write, FAIL);
@@ -997,13 +992,13 @@ H5D_write(H5D_t *dataset, const H5T_t *mem_type, const H5P_t *mem_space,
     nelmts = H5P_get_npoints(dataset->space);
     src_size = nelmts * H5T_get_size(mem_type);
     dst_size = nelmts * H5T_get_size(dataset->type);
-    conv_buf = H5MM_xmalloc(MAX(src_size, dst_size));
+    tconv_buf = H5MM_xmalloc(MAX(src_size, dst_size));
 #endif
 
     /*
      * Locate the type conversion function.
      */
-    if (NULL == (conv_func = H5T_find(mem_type, dataset->type))) {
+    if (NULL == (tconv_func = H5T_find(mem_type, dataset->type))) {
 	HGOTO_ERROR(H5E_DATASET, H5E_UNSUPPORTED, FAIL,
 		    "unable to convert between src and dest data types");
     }
@@ -1011,12 +1006,12 @@ H5D_write(H5D_t *dataset, const H5T_t *mem_type, const H5P_t *mem_space,
     /*
      * Gather data into the data type conversion buffer.
      */
-    HDmemcpy(conv_buf, buf, src_size);
+    HDmemcpy(tconv_buf, buf, src_size);
 
     /*
      * Perform data type conversion.
      */
-    if ((conv_func) (src_id, dst_id, nelmts, conv_buf, NULL) < 0) {
+    if ((tconv_func) (src_id, dst_id, nelmts, tconv_buf, NULL) < 0) {
 	HGOTO_ERROR(H5E_DATASET, H5E_CANTINIT, FAIL,
 		    "data type conversion failed");
     }
@@ -1039,7 +1034,7 @@ H5D_write(H5D_t *dataset, const H5T_t *mem_type, const H5P_t *mem_space,
     size[i] = H5T_get_size (dataset->type);
 #endif
     if (H5F_arr_write(dataset->ent.file, &(dataset->layout), size, offset,
-		      zero, size, conv_buf) < 0) {
+		      zero, size, tconv_buf) < 0) {
 	HGOTO_ERROR(H5E_IO, H5E_WRITEERROR, FAIL, "write failed");
     }
     ret_value = SUCCEED;
@@ -1047,6 +1042,6 @@ H5D_write(H5D_t *dataset, const H5T_t *mem_type, const H5P_t *mem_space,
   done:
     if (src_id >= 0) H5A_dec_ref(src_id);
     if (dst_id >= 0) H5A_dec_ref(dst_id);
-    conv_buf = H5MM_xfree(conv_buf);
+    tconv_buf = H5MM_xfree(tconv_buf);
     FUNC_LEAVE(ret_value);
 }
diff --git a/src/H5P.c b/src/H5P.c
index 4ea8117..f6b0ff1 100644
--- a/src/H5P.c
+++ b/src/H5P.c
@@ -23,11 +23,11 @@ static char             RcsId[] = "@(#)$Revision$";
 #include <H5Oprivate.h>         /*object headers                  */
 #include <H5Pprivate.h>         /* Data-space functions                   */
 
-#define PABLO_MASK      H5P_mask
 
 /* Interface initialization */
-static intn             interface_initialize_g = FALSE;
+#define PABLO_MASK      H5P_mask
 #define INTERFACE_INIT  H5P_init_interface
+static intn             interface_initialize_g = FALSE;
 static herr_t           H5P_init_interface(void);
 static void             H5P_term_interface(void);
 
@@ -892,3 +892,60 @@ H5Pset_space(hid_t sid, intn rank, const size_t *dims)
     /* Normal function cleanup */
     FUNC_LEAVE(ret_value);
 }
+
+/*-------------------------------------------------------------------------
+ * Function:	H5P_find
+ *
+ * Purpose:	Given source and destination data spaces (SRC and DST) this
+ *		function locates the data space conversion functions and
+ *		initializes CONV to point to them.
+ *
+ * Return:	Success:	Pointer to a data space conversion callback
+ *				list.
+ *
+ *		Failure:	NULL
+ *
+ * Programmer:	Robb Matzke
+ *              Wednesday, January 21, 1998
+ *
+ * Modifications:
+ *
+ *-------------------------------------------------------------------------
+ */
+const H5P_conv_t *
+H5P_find (const H5P_t *src, const H5P_t *dst)
+{
+    static H5P_conv_t		_conv;
+    static const H5P_conv_t 	*conv = NULL;
+    
+    FUNC_ENTER (H5P_find, NULL);
+
+    /* Check args */
+    assert (src && H5P_SIMPLE==src->type);
+    assert (dst && H5P_SIMPLE==dst->type);
+
+    /*
+     * We can't do conversion if the source and destination select a
+     * different number of data points.
+     */
+    if (H5P_get_npoints (src) != H5P_get_npoints (dst)) {
+	HRETURN_ERROR (H5E_DATASPACE, H5E_BADRANGE, NULL,
+		       "src and dest data spaces are different sizes");
+    }
+
+    /*
+     * Initialize pointers.  This will eventually be a table lookup based
+     * on the source and destination data spaces, similar to H5T_find(), but
+     * for now we only support simple data spaces.
+     */
+    if (!conv) {
+	_conv.init = H5P_simp_init;
+	_conv.fgath = H5P_simp_fgath;
+	_conv.mscat = H5P_simp_mscat;
+	_conv.mgath = H5P_simp_mgath;
+	_conv.fscat = H5P_simp_fscat;
+	conv = &_conv;
+    }
+    
+    FUNC_LEAVE (conv);
+}
diff --git a/src/H5Pprivate.h b/src/H5Pprivate.h
index 3a2f804..e5dca7e 100644
--- a/src/H5Pprivate.h
+++ b/src/H5Pprivate.h
@@ -10,51 +10,98 @@
  *                                                                          *
  ****************************************************************************/
 
-/* $Id$ */
-
 /*
  * This file contains private information about the H5P module
  */
-
 #ifndef _H5Pprivate_H
 #define _H5Pprivate_H
+
 #include <H5Ppublic.h>
 
 /* Private headers needed by this file */
 #include <H5private.h>
-#include <H5Gprivate.h>         /*for H5G_entry_t */
+#include <H5Gprivate.h>         /*for H5G_entry_t                            */
+#include <H5Oprivate.h>
+
+#define H5P_RESERVED_ATOMS  2
 
 /* Flags to indicate special dataspace features are active */
 #define H5P_VALID_MAX   0x01
 #define H5P_VALID_PERM  0x02
 
 typedef struct H5P_simple_t {
-    intn                    rank;       /*number of dimensions                  */
-    intn                    dim_flags;  /*dimension flags                       */
-    size_t                 *size;       /*dimension sizes                       */
-    size_t                 *max;        /*maximum dimension sizes               */
-    intn                   *perm;       /*dimension permutations                */
+    intn        rank;                   /*number of dimensions               */
+    intn        dim_flags;              /*dimension flags                    */
+    size_t      *size;                  /*dimension sizes                    */
+    size_t      *max;                   /*maximum dimension sizes            */
+    intn        *perm;                  /*dimension permutations             */
 } H5P_simple_t;
 
 typedef struct {
-    H5P_class_t             type;       /*type of dimensionality object         */
+    H5P_class_t         type;           /*type of dimensionality object      */
     union {
-        H5P_simple_t            simple;         /*simple dimensionality information   */
+        H5P_simple_t    simple;         /*simple dimensionality information  */
     } u;
 } H5P_t;
 
-#define H5P_RESERVED_ATOMS  2
+/*
+ * This structure contains information about how the elements of a data space
+ * are numbered.
+ */
+typedef struct H5P_number_t {
+    int		_place_holder;		/*remove this field!*/
+} H5P_number_t;
+
+/*
+ * Callbacks for data space conversion.
+ */
+typedef struct H5P_tconv_t {
+    /* Initialize element numbering information */
+    size_t (*init)(const struct H5O_layout_t *layout, const H5P_t *mem_space,
+		   const H5P_t *file_space, H5P_number_t *numbering/*out*/);
+
+    /* Gather elements from disk to type conversion buffer */
+    size_t (*fgath)(H5F_t *f, const struct H5O_layout_t *layout,
+		    size_t elmt_size, const H5P_t *file_space,
+		    const H5P_number_t *numbering, intn start, intn nelmts,
+		    void *tconv_buf/*out*/);
+
+    /* Scatter elements from type conversion buffer to application buffer */
+    herr_t (*mscat)(const void *tconv_buf, size_t elmt_size,
+		    const H5P_t *mem_space, const H5P_number_t *numbering,
+		    intn start, intn nelmts, void *buf/*out*/);
+
+    /* Gather elements from app buffer to type conversion buffer */
+    size_t (*mgath)(void /*fill out later*/);
+
+    /* Scatter elements from type conversion buffer to disk */
+    herr_t (*fscat)(void /*fill out later*/);
+} H5P_conv_t;
+
+H5P_t *H5P_copy (const H5P_t *src);
+herr_t H5P_close (H5P_t *ds);
+size_t H5P_get_npoints (const H5P_t *ds);
+intn H5P_get_ndims (const H5P_t *ds);
+intn H5P_get_dims (const H5P_t *ds, size_t dims[]/*out*/);
+herr_t H5P_modify (H5F_t *f, H5G_entry_t *ent, const H5P_t *space);
+H5P_t *H5P_read (H5F_t *f, H5G_entry_t *ent);
+intn H5P_cmp (const H5P_t *ds1, const H5P_t *ds2);
+hbool_t H5P_is_simple (const H5P_t *sdim);
+uintn H5P_nelem (const H5P_t *space);
+const H5P_conv_t *H5P_find (const H5P_t *src, const H5P_t *dst);
 
-H5P_t                  *H5P_copy(const H5P_t *src);
-herr_t                  H5P_close(H5P_t *ds);
-size_t                  H5P_get_npoints(const H5P_t *ds);
-intn                    H5P_get_ndims(const H5P_t *ds);
-intn                    H5P_get_dims(const H5P_t *ds, size_t dims[] /*out */ );
-herr_t                  H5P_modify(H5F_t *f, H5G_entry_t *ent, const H5P_t *space);
-H5P_t                  *H5P_read(H5F_t *f, H5G_entry_t *ent);
-intn                    H5P_cmp(const H5P_t *ds1, const H5P_t *ds2);
-
-hbool_t                 H5P_is_simple(const H5P_t *sdim);
-uintn                   H5P_nelem(const H5P_t *space);
+/* Conversion functions for simple data spaces */
+size_t H5P_simp_init (const struct H5O_layout_t *layout,
+		      const H5P_t *mem_space, const H5P_t *file_space,
+		      H5P_number_t *numbering/*out*/);
+size_t H5P_simp_fgath (H5F_t *f, const struct H5O_layout_t *layout,
+		       size_t elmt_size, const H5P_t *file_space,
+		       const H5P_number_t *numbering, intn start, intn nelmts,
+		       void *tconv_buf/*out*/);
+herr_t H5P_simp_mscat (const void *tconv_buf, size_t elmt_size,
+		       const H5P_t *mem_space, const H5P_number_t *numbering,
+		       intn start, intn nelmts, void *buf/*out*/);
+size_t H5P_simp_mgath (void);
+herr_t H5P_simp_fscat (void);
 
 #endif
diff --git a/src/Makefile.in b/src/Makefile.in
index 7bb2f81..912a901 100644
--- a/src/Makefile.in
+++ b/src/Makefile.in
@@ -18,7 +18,8 @@ LIB_SRC=H5.c H5A.c H5AC.c H5B.c H5C.c H5D.c H5E.c H5F.c H5Farray.c H5Fcore.c  \
 	H5Ffamily.c H5Fistore.c H5Flow.c H5Fsec2.c H5Fsplit.c H5Fstdio.c      \
         H5G.c H5Gent.c H5Gnode.c H5Gstab.c H5H.c H5M.c H5MF.c H5MM.c H5O.c    \
         H5Ocont.c H5Odtype.c H5Oefl.c H5Olayout.c H5Oname.c H5Onull.c         \
-	H5Osdspace.c H5Ostab.c H5P.c H5T.c H5Tconv.c H5Tinit.c H5V.c
+	H5Osdspace.c H5Ostab.c H5P.c H5Psimp.c H5T.c H5Tconv.c H5Tinit.c      \
+	H5V.c
 
 LIB_OBJ=$(LIB_SRC:.c=.o)