Added methods to return domain/grid shape

- get_global_shape() returns niglobal, njglobal from domain type.
- get_global_grid_shape() returns niglobal, njglobal by calling
  get_global_shape().
- This avoids exposing members inside opaque types otherwise needed
  for initializing under MCT.

src/core/MOM_grid.F90

@@ -5,6 +5,7 @@ module MOM_grid
 
 use MOM_hor_index, only : hor_index_type, hor_index_init
 use MOM_domains, only : MOM_domain_type, get_domain_extent, compute_block_extent
+use MOM_domains, only : get_global_shape
 use MOM_error_handler, only : MOM_error, MOM_mesg, FATAL
 use MOM_file_parser, only : get_param, log_param, log_version, param_file_type
 
@@ -13,7 +14,7 @@ module MOM_grid
 #include <MOM_memory.h>
 
 public MOM_grid_init, MOM_grid_end, set_derived_metrics, set_first_direction
-public isPointInCell, hor_index_type
+public isPointInCell, hor_index_type, get_global_grid_size
 
 !> Ocean grid type. See mom_grid for details.
 type, public :: ocean_grid_type
@@ -443,6 +444,16 @@ subroutine set_first_direction(G, y_first)
   G%first_direction = y_first
 end subroutine set_first_direction
 
+!> Return global shape of horizontal grid
+subroutine get_global_grid_size(G, niglobal, njglobal)
+  type(ocean_grid_type), intent(inout) :: G !< The horizontal grid type
+  integer,               intent(out)   :: niglobal !< i-index global size of grid
+  integer,               intent(out)   :: njglobal !< j-index global size of grid
+
+  call get_global_shape(G%domain, niglobal, njglobal)
+
+end subroutine get_global_grid_size
+
 !> Allocate memory used by the ocean_grid_type and related structures.
 subroutine allocate_metrics(G)
   type(ocean_grid_type), intent(inout) :: G !< The horizontal grid type

src/framework/MOM_domains.F90

@@ -60,7 +60,7 @@ module MOM_domains
 public :: To_East, To_West, To_North, To_South, To_All, Omit_Corners
 public :: create_group_pass, do_group_pass, group_pass_type
 public :: start_group_pass, complete_group_pass
-public :: compute_block_extent
+public :: compute_block_extent, get_global_shape
 
 interface pass_var
   module procedure pass_var_3d, pass_var_2d
@@ -1599,4 +1599,15 @@ subroutine get_domain_extent(Domain, isc, iec, jsc, jec, isd, ied, jsd, jed, &
 
 end subroutine get_domain_extent
 
+!> Returns the global shape of h-point arrays
+subroutine get_global_shape(domain, niglobal, njglobal)
+  type(MOM_domain_type), intent(in)  :: domain !< MOM domain
+  integer,               intent(out) :: niglobal !< i-index global size of h-point arrays
+  integer,               intent(out) :: njglobal !< j-index global size of h-point arrays
+
+  niglobal = domain%niglobal
+  njglobal = domain%njglobal
+
+end subroutine get_global_shape
+
 end module MOM_domains