CarpetIOHDF5: use simple_extents rather than storage size on disk

storage size is literally the amount of space used on disk, so if eg
compression is used, this is much smaller than the amount of space
required to hold the data in memory.

Also change type of data read in to what the memory dataspace is not
what the dataspace on disk is. This way HDF5 actually converts from the
on-disk representation to the in-memory one.

1 files changed, 10 insertions, 4 deletions

diff --git a/Carpet/CarpetIOHDF5/src/Input.cc b/Carpet/CarpetIOHDF5/src/Input.cc
index 21a855a01..a2e64245d 100644
--- a/Carpet/CarpetIOHDF5/src/Input.cc
+++ b/Carpet/CarpetIOHDF5/src/Input.cc
@@ -993,16 +993,19 @@ static list<fileset_t>::iterator OpenFileSet (const cGH* const cctkGH,
     HDF5_ERROR (datatype = H5Dget_type(dataset));
     HDF5_ERROR (old_data = H5Tequal(datatype, H5T_NATIVE_CHAR));
     if (old_data) {
+        hid_t dataspace;
+        HDF5_ERROR (dataspace = H5Dget_space(dataset));
         /* old data that stored this as an array of chars */
         CCTK_WARN (CCTK_WARN_ALERT, "Old-style checkpoint data found.");
-        HDF5_ERROR (len = H5Dget_storage_size(dataset) + 1);
+        HDF5_ERROR (len = H5Sget_simple_extent_npoints(dataspace) + 1);
+        HDF5_ERROR (H5Sclose(dataspace));
     } else {
         HDF5_ERROR (len = H5Tget_size(datatype));
     }
     vector<char> parameter_buf(len);
     char* parameters = &parameter_buf[0];
 
-    HDF5_ERROR (H5Dread (dataset, datatype, H5S_ALL, H5S_ALL,
+    HDF5_ERROR (H5Dread (dataset, H5T_NATIVE_CHAR, H5S_ALL, H5S_ALL,
                          H5P_DEFAULT, parameters));
     HDF5_ERROR (H5Dclose (dataset));
     HDF5_ERROR (H5Tclose (datatype));
@@ -1096,16 +1099,19 @@ static void ReadMetadata (fileset_t& fileset, hid_t file)
     HDF5_ERROR (datatype = H5Dget_type(dataset));
     HDF5_ERROR (old_data = H5Tequal(datatype, H5T_NATIVE_CHAR));
     if (old_data) {
+        hid_t dataspace;
+        HDF5_ERROR (dataspace = H5Dget_space(dataset));
         /* old data that stored this as an array of chars */
         CCTK_WARN (CCTK_WARN_ALERT, "Old-style checkpoint data found.");
-        HDF5_ERROR (len = H5Dget_storage_size(dataset) + 1);
+        HDF5_ERROR (len = H5Sget_simple_extent_npoints(dataspace) + 1);
+        HDF5_ERROR (H5Sclose(dataspace));
     } else {
         HDF5_ERROR (len = H5Tget_size(datatype));
     }
     vector<char> gs_str_buf(len);
     char* gs_str = &gs_str_buf[0];
 
-    HDF5_ERROR (H5Dread (dataset, datatype, H5S_ALL, H5S_ALL,
+    HDF5_ERROR (H5Dread (dataset, H5T_NATIVE_CHAR, H5S_ALL, H5S_ALL,
                          H5P_DEFAULT, gs_str));
     HDF5_ERROR (H5Dclose (dataset));
     HDF5_ERROR (H5Tclose (datatype));