abort if boundary width is very large, which is most likely an error

Currently if a user schedules the routine calling Boundary_RegisterGroupForBC
in LEVEL mode (which is the correct mode), cctk_nghostzones is undefined and
Carpet fills it with the deadbeef value (666). Passing 666 to
Boundary_RegisterGroupForBC leads to silently incorrect results as it often
prevents the BC from being applied at all (there is a check in many boundary
routines that returns if the domain is too small, presumably to support 1 point
wide 1d domains).

This patch checks the boundary width requested and aborts if the width is
larger than 100. This is the same threshold that the symmetry thorns already
use to abort a run.

This prevents a user error (seen it twice so far) and should not as far as I
can tell affect any correct code (unless we ever actually encounter a boundary
wider than 100 points in which case we are in trouble anyway).

This patch resulted from ticket #1508 "abort if boundary widht is very wide
(>100 points)"


git-svn-id: http://svn.cactuscode.org/arrangements/CactusBase/Boundary/trunk@321 6a38eb6e-646e-4a02-a296-d141613ad6c4

1 files changed, 3 insertions, 0 deletions

diff --git a/src/RobinBoundary.c b/src/RobinBoundary.c
index 46c08d5..3ca194d 100644
--- a/src/RobinBoundary.c
+++ b/src/RobinBoundary.c
@@ -914,6 +914,9 @@ static int ApplyBndRobin (const cGH *GH,
     }
   }
 
+  /* sanity check on width of boundary,  */
+  BndSanityCheckWidths(GH, first_var, gdim, in_widths, "Robin");
+
   /* Robin boundaries need the underlying grid coordinates */
   sprintf (coord_system_name, "cart%dd", gdim);
   if (CCTK_CoordSystemHandle (coord_system_name) < 0)