Find Modbus in your file system with CMake

FindModbus.cmake

# - Find Modbus library
# Find the Modbus headers and libraries.
#
#  MODBUS_INCLUDE_DIRS - where to find modbus.h
#  MODBUS_LIBRARIES    - List of libraries when using modbus.
#  MODBUS_FOUND        - True if modbus library found.
#

# Based on Findquatlib.cmake, Original Author:
# 2009-2010 Ryan Pavlik <rpavlik@iastate.edu> <abiryan@ryand.net>
# http://academic.cleardefinition.com
# Iowa State University HCI Graduate Program/VRAC
#
# Copyright Iowa State University 2009-2010.
# Distributed under the Boost Software License, Version 1.0.
# (See accompanying file LICENSE_1_0.txt or copy at
# http://www.boost.org/LICENSE_1_0.txt)

set(MODBUS_ROOT_DIR
	"${MODBUS_ROOT_DIR}"
	CACHE
	PATH
	"Root directory to search for libmodbus")

# Look for the header file.
find_path(MODBUS_INCLUDE_DIR
	NAMES
	modbus.h
	HINTS
	"${MODBUS_ROOT_DIR}"
	PATH_SUFFIXES
	include
	PATHS
	/usr/local
	/usr/include/modbus
	/usr/local/include/modbus)

# Look for the library.
find_library(MODBUS_LIBRARY
	NAMES
	libmodbus.a
	modbus.a
	modbus
	PATH_SUFFIXES
	lib
	PATHS
	/usr
	/usr/local)

message(STATUS "Here" ${MODBUS_LIBRARY})

# handle the QUIETLY and REQUIRED arguments and set MODBUS_FOUND to TRUE if
# all listed variables are TRUE
include(FindPackageHandleStandardArgs)
find_package_handle_standard_args(Modbus
	DEFAULT_MSG
	MODBUS_LIBRARY
	MODBUS_INCLUDE_DIR)

if(MODBUS_FOUND)
	set(MODBUS_LIBRARIES ${MODBUS_LIBRARY})
	set(MODBUS_INCLUDE_DIRS ${MODBUS_INCLUDE_DIR})

	mark_as_advanced(MODBUS_ROOT_DIR)
else()
	set(MODBUS_LIBRARIES)
	set(MODBUS_INCLUDE_DIRS)
endif()

mark_as_advanced(MODBUS_LIBRARY MODBUS_INCLUDE_DIR)