eckpoint cctk_delta_timesvn

the PUGH driver currently did not checkpoint the stepsize which makes using it
with adaptive timestepping hard. Carpet on the other hand checkpoints the
stepsize.

This patch writes cckt_delta_time into checkpoints. When reading a checkpoint
file that does not set the timestep, the user will see level 1 warning that the
attribute cctk_delta_time was not found but the code will not abort and will
behave as it does right now otherwise (which is to use cctk_delta_time based on
the values from parameters/set in basegrid).


git-svn-id: http://svn.cactuscode.org/arrangements/CactusPUGHIO/IOHDF5Util/trunk@174 7842ec3a-9562-4be5-9c5b-06ba18f2b668

2 files changed, 13 insertions, 4 deletions

diff --git a/src/DumpUtils.c b/src/DumpUtils.c
index ad99e00..d559db7 100644
--- a/src/DumpUtils.c
+++ b/src/DumpUtils.c
@@ -429,6 +429,8 @@ void IOHDF5Util_DumpGHExtensions (const cGH *GH, hid_t file)
   WRITE_ATTRIBUTE ("unchunked", &ioUtilGH->unchunked, group, myGH, 0,
                    H5T_NATIVE_INT);
   WRITE_ATTRIBUTE ("cctk_time", &GH->cctk_time, group, myGH, 0, HDF5_REAL);
+  WRITE_ATTRIBUTE ("cctk_delta_time", &GH->cctk_delta_time, group, myGH, 0,
+                   HDF5_REAL);
   WRITE_ATTRIBUTE ("cctk_iteration", &GH->cctk_iteration, group, myGH, 0,
                    H5T_NATIVE_INT);
   version = CCTK_FullVersion ();
diff --git a/src/RecoverVar.c b/src/RecoverVar.c
index 19a6cb3..ace099c 100644
--- a/src/RecoverVar.c
+++ b/src/RecoverVar.c
@@ -193,7 +193,7 @@ int IOHDF5Util_RecoverVariables (cGH *GH, const fileinfo_t *fileinfo)
 int IOHDF5Util_RecoverGHextensions (cGH *GH, const fileinfo_t *fileinfo)
 {
   hid_t group;
-  CCTK_REAL realBuffer;
+  CCTK_REAL realBuffer[2];
   CCTK_INT4 int4Buffer[3];
 
 
@@ -208,7 +208,13 @@ int IOHDF5Util_RecoverGHextensions (cGH *GH, const fileinfo_t *fileinfo)
     {
       READ_ATTRIBUTE (group, "cctk_iteration", HDF5_INT4, &int4Buffer[1]);
       READ_ATTRIBUTE (group, "main_loop_index", HDF5_INT4, &int4Buffer[2]);
-      READ_ATTRIBUTE (group, "cctk_time", HDF5_REAL, &realBuffer);
+      READ_ATTRIBUTE (group, "cctk_time", HDF5_REAL, &realBuffer[0]);
+      // pre rev 173 checkpoints do not contain cctk_delta_time. When reading
+      // such a checkpoint, we output a warning and continue to use the old
+      // cctk_delta_time. For this we need to initialize realBuffer[1] since we
+      // cannot tell if READ_ATTRIBUTE succeeded or not.
+      realBuffer[1] = GH->cctk_delta_time;
+      READ_ATTRIBUTE (group, "cctk_delta_time", HDF5_REAL, &realBuffer[1]);
 
       HDF5_ERROR (H5Gclose (group));
     }
@@ -227,14 +233,15 @@ int IOHDF5Util_RecoverGHextensions (cGH *GH, const fileinfo_t *fileinfo)
   CACTUS_MPI_ERROR (MPI_Bcast (int4Buffer, 3, PUGH_MPI_INT4, 0,MPI_COMM_WORLD));
   if (int4Buffer[0])
   {
-    CACTUS_MPI_ERROR (MPI_Bcast (&realBuffer, 1, PUGH_MPI_REAL, 0,
+    CACTUS_MPI_ERROR (MPI_Bcast (realBuffer, 2, PUGH_MPI_REAL, 0,
                                  MPI_COMM_WORLD));
   }
 #endif
 
   if (int4Buffer[0])
   {
-    GH->cctk_time = realBuffer;
+    GH->cctk_time = realBuffer[0];
+    GH->cctk_delta_time = realBuffer[1];
     GH->cctk_iteration = int4Buffer[1];
     CCTK_SetMainLoopIndex ((int) int4Buffer[2]);
   }