ENH: Support to find CABLE utility if it is installed.

Modules/FindCABLE.cmake

@@ -0,0 +1,36 @@
+#
+# This module finds if CABLE is installed and determines where the
+# include files and libraries are.  This code sets the following variables:
+#
+#  CABLE              = the full path to the cable executable
+#  CABLE_TCL_LIBRARY  = the full path to the Tcl wrapper facility library
+#  CABLE_ROOT         = the full path to the root of the cable installation
+#
+#  To build Tcl wrappers, you should add shared library and link it to
+#  ${CABLE_TCL_LIBRARY}.  You should also add ${CABLE_ROOT}/include as
+#  an include directory.
+#
+
+# Use some tricks to find the cable executable relative to somewhere
+# in the system search path.  CMake will collapse the relative paths
+# automatically.
+FIND_PROGRAM(CABLE
+  NAMES cable
+        ../share/Cable/bin/cable
+        ../Cable/bin/cable
+  PATHS /usr/share/Cable/bin
+        /usr/local/share/Cable/bin
+        "C:/Program Files/Cable/bin"
+)
+
+# Get the path where the executable sits, but without the executable
+# name on it.
+GET_FILENAME_COMPONENT(CABLE_ROOT_BIN ${CABLE} PATH)
+
+# Find the root of the CABLE installation based on the executable's
+# location.
+FIND_PATH(CABLE_ROOT include/wrapCalls.h ${CABLE_ROOT_BIN}/..)
+
+# Find the WrapTclFacility library in a path relative to the root of
+# the CABLE installation.
+FIND_LIBRARY(CABLE_TCL_LIBRARY NAMES WrapTclFacility PATHS ${CABLE_ROOT}/lib)