Add master option for subgrid model

Implements #422 (closed).

configure.ac

@@ -41,6 +41,42 @@ AX_CHECK_ENABLE_DEBUG
 AC_PROG_CC
 AM_PROG_CC_C_O
 
+
+# Subgrid options
+# if you add a restriction (e.g. not cooling, chemistry or hydro)
+# you will need to check for overwrite after ready the parameter
+# see AC_ARG_WITH for cooling for an example.
+AC_ARG_WITH([subgrid],
+	[AS_HELP_STRING([--with-subgrid=<subgrid>],
+		[Name of the subgrid methods. Inexperiented user should start from here @<:@none, gear default: none@:>@]
+	)],
+	[with_subgrid="$withval"],
+	[with_subgrid=none]
+)
+
+# default values
+with_subgrid_cooling=none
+with_subgrid_chemistry=none
+with_subgrid_hydro=none
+
+case "$with_subgrid" in
+   none)
+      ;;
+   gear)
+	with_subgrid_cooling=grackle
+	with_subgrid_chemistry=gear
+	with_subgrid_hydro=gadget2
+	;;
+   eagle)
+	with_subgrid_cooling=EAGLE
+	with_subgrid_chemistry=EAGLE
+   *)
+      AC_MSG_ERROR([Unknown subgrid: $with_subgrid])
+      ;;
+esac
+
+
+
 # If debug is selected then we also define SWIFT_DEVELOP_MODE to control
 # any developer code options.
 if test "x$ax_enable_debug" != "xno"; then
@@ -784,6 +820,15 @@ AC_ARG_WITH([hydro],
    [with_hydro="$withval"],
    [with_hydro="gadget2"]
 )
+
+if test "$with_subgrid" != "none"; then
+   if test "$with_hydro" != "gadget2"; then
+      AC_MSG_ERROR([Cannot provide with-subgrid and with-hydro together])
+   else
+      with_hydro="$with_subgrid_hydro"
+   fi
+fi
+
 case "$with_hydro" in
    gadget2)
       AC_DEFINE([GADGET2_SPH], [1], [Gadget-2 SPH])
@@ -967,6 +1012,15 @@ AC_ARG_WITH([cooling],
    [with_cooling="$withval"],
    [with_cooling="none"]
 )
+
+if test "$with_subgrid" != "none"; then
+   if test "$with_cooling" != "none"; then
+      AC_MSG_ERROR([Cannot provide with-subgrid and with-cooling together])
+   else
+      with_cooling="$with_subgrid_cooling"
+   fi
+fi
+
 case "$with_cooling" in
    none)
       AC_DEFINE([COOLING_NONE], [1], [No cooling function])
@@ -996,6 +1050,15 @@ AC_ARG_WITH([chemistry],
    [with_chemistry="$withval"],
    [with_chemistry="none"]
 )
+
+if test "$with_subgrid" != "none"; then
+   if test "$with_chemistry" != "none"; then
+      AC_MSG_ERROR([Cannot provide with-subgrid and with-chemistry together])
+   else
+      with_chemistry="$with_subgrid_chemistry"
+   fi
+fi
+
 case "$with_chemistry" in
    none)
       AC_DEFINE([CHEMISTRY_NONE], [1], [No chemistry function])
@@ -1056,7 +1119,6 @@ AC_ARG_WITH([multipole-order],
 )
 AC_DEFINE_UNQUOTED([SELF_GRAVITY_MULTIPOLE_ORDER], [$with_multipole_order], [Multipole order])
 
-
 # Check for git, needed for revision stamps.
 AC_PATH_PROG([GIT_CMD], [git])
 AC_SUBST([GIT_CMD])