H5D.write/read: test reference read and write

Author: pantxo

src/__H5D__.cc

@@ -506,6 +506,9 @@ See original function at \
 %!test
 %! h5ex_t_cmpd ()
 
+%!test
+%! h5ex_t_objref ()
+
 */
 
 // PKG_ADD: autoload ("__H5D_write__", "__H5D__.oct");

test/hdf5_matlab_examples/h5ex_t_objref.m

@@ -0,0 +1,129 @@
+function h5ex_t_objref
+  %%**************************************************************************
+  %%  This example is adapted from the original file generously provided
+  %%  by a user to the HDFGroup examples.
+  %%
+  %% This example shows how to read and write object references
+  %% to a dataset.  The program first creates objects in the
+  %% file and writes references to those objects to a dataset
+  %% with a dataspace of DIM0, then closes the file.  Next, it
+  %% reopens the file, dereferences the references, and outputs
+  %% the names of their targets to the screen.
+  %%
+  %%  This file is intended for use with HDF5 Library version 1.8
+  %%  EDIT: Also tested with version 1.10.
+  %%**************************************************************************
+
+  fileName       = tempname ();
+  DATASET        = 'DS1';
+  DIM0           = 2;
+
+  dims  =DIM0;
+
+  %%
+  %% Create a new file using the default properties.
+  %%
+  file = H5F.create (fileName, 'H5F_ACC_TRUNC', 'H5P_DEFAULT', 'H5P_DEFAULT');
+
+  %%
+%%%% Create a dataset with a scalar dataspace.
+  %%
+  space = H5S.create ('H5S_NULL');
+  obj = H5D.create (file, 'DS2', 'H5T_STD_I32LE', space, 'H5P_DEFAULT');
+  H5D.close (obj);
+  H5S.close (space);
+
+  %%
+  %% Create a group.
+  %%
+  size_hint=H5ML.get_constant_value('H5P_DEFAULT');
+  obj = H5G.create (file, 'G1', size_hint);
+  H5G.close (obj);
+
+  %%
+  %% Create references to the previously created objects.  Passing -1
+  %% as space_id causes this parameter to be ignored.  Other values
+  %% besides valid dataspaces result in an error.
+  %%
+  wdata(1) = H5R.create (file, 'G1', 'H5R_OBJECT', -1);
+  wdata(2) = H5R.create (file, 'DS2', 'H5R_OBJECT', -1);
+
+  %%
+  %% Create dataspace.  Setting maximum size to [] sets the maximum
+  %% size to be the current size.
+  %%
+  space = H5S.create_simple (1,fliplr(dims), []);
+
+  %%
+  %% Create the dataset and write the object references to it.
+  %%
+  dset = H5D.create (file, DATASET, 'H5T_STD_REF_OBJ', space, 'H5P_DEFAULT');
+  H5D.write (dset, 'H5T_STD_REF_OBJ', 'H5S_ALL', 'H5S_ALL', 'H5P_DEFAULT',wdata);
+
+  %%
+  %% Close and release resources.
+  %%
+  H5D.close (dset);
+  H5S.close (space);
+  H5F.close (file);
+
+  %%
+  %% Now we begin the read section of this example.  Here we assume
+  %% the dataset has the same name and rank, but can have any size.
+  %%
+
+  %%
+  %% Open file and dataset.
+  %%
+  file = H5F.open (fileName, 'H5F_ACC_RDONLY', 'H5P_DEFAULT');
+  dset = H5D.open (file, DATASET);
+
+  %%
+  %% Get dataspace.
+  %%
+  space = H5D.get_space (dset);
+  [~, dims] = H5S.get_simple_extent_dims (space);
+  dims = fliplr(dims);
+
+  %%
+  %% Read the data.
+  %%
+  rdata = H5D.read (dset, 'H5T_STD_REF_OBJ', 'H5S_ALL', 'H5S_ALL', 'H5P_DEFAULT');
+
+  %%
+  %% Output the data to the screen.
+  %%
+  links = {};
+  for i=1: dims(1)
+    obj = H5R.dereference (dset, 'H5R_OBJECT', rdata(i));
+    objtype = H5R.get_obj_type (dset, 'H5R_OBJECT', rdata(i));
+    
+    %%
+    %% Retrieve the name.
+    %%
+    name = H5I.get_name(obj);
+    
+    switch (objtype)
+      case H5ML.get_constant_value('H5O_TYPE_GROUP')
+        links = [links ["Group " name]];
+      case H5ML.get_constant_value('H5O_TYPE_DATASET')
+        links = [links ["Dataset " name]];
+      case H5ML.get_constant_value('H5O_TYPE_TYPE')
+        links = [links ["Type " name]];
+    end
+    H5O.close (obj);
+  end
+
+  %%
+  %% Close and release resources.
+  %%
+  H5D.close (dset);
+  H5S.close (space);
+  H5F.close (file);
+  delete (fileName);
+
+  ## FIXME: we shouldn't have to transpose here
+  assert (rdata', wdata);
+  
+  assert (links, {"Group /G1", "Dataset /DS2"});
+endfunction