Don't hyperslab/output zero-sized grid variables.

Finally closes PR CactusPUGH/1243: "Segmentation fault in PUGHSlab".


git-svn-id: http://svn.cactuscode.org/arrangements/CactusBase/IOASCII/trunk@177 94b1c47f-dcfd-45ef-a468-0854c0e9e350

1 files changed, 15 insertions, 9 deletions

diff --git a/src/Write2D.c b/src/Write2D.c
index 66e25f3..4c7db4d 100644
--- a/src/Write2D.c
+++ b/src/Write2D.c
@@ -219,23 +219,31 @@ int IOASCII_Write2D (const cGH *GH, int vindex, const char *alias)
   sprintf (format[2], "\t\t%%%s", out_format);
 
   /* processor 0 opens the files on the first trip through */
+  fileset = NULL;
   myproc = CCTK_MyProc (GH);
   if (myproc == 0)
   {
     fileset = OpenFile (GH, fullname, alias, gdata.dim,
                         have_coords ? coord_lower : NULL, maxdir);
   }
-  else
-  {
-    fileset = NULL;
-  }
 
   /* get the extents of the variable */
   CCTK_GroupgshVI (GH, gdata.dim, extent_int, vindex);
 
+  /* get the total number of grid points to check for zero-sized variables */
+  for (dir = 0, hsize[0] = 1; dir < gdata.dim; dir++)
+  {
+    hsize[0] *= extent_int[dir];
+  }
+
   /* now do the actual I/O looping over all directions */
   for (dir = 0; dir < maxdir; dir++)
   {
+    if (hsize[0] <= 0)
+    {
+      continue;
+    }
+
     /* get the directions to span the hyperslab */
     if (dir == 0)
     {
@@ -288,6 +296,7 @@ int IOASCII_Write2D (const cGH *GH, int vindex, const char *alias)
       continue;
     }
 
+    hdata[0] = hdata[1] = hdata[2];
     if (myproc == 0)
     {
       /* allocate hyperslab buffers */
@@ -309,7 +318,7 @@ int IOASCII_Write2D (const cGH *GH, int vindex, const char *alias)
     Hyperslab_FreeMapping (mapping);
 
     /* and dump the data to file */
-    if (myproc == 0 && fileset)
+    if (fileset)
     {
       if (num_returned_hslabs == num_requested_hslabs)
       {
@@ -338,10 +347,7 @@ int IOASCII_Write2D (const cGH *GH, int vindex, const char *alias)
 
       /* clean up */
       free (hdata[0]);
-      if (hdata[1])
-      {
-        free (hdata[1]);
-      }
+      free (hdata[1]);
 
     } /* end of outputting the data by processor 0 */