Building a library using autotools from cmake
I think that you'd be better off using the ExternalProject feature of cmake. I guess you have your project and have libantrl in a sub directory?
project
+- libantlr
+- mysrc
---- etc ----
If that's the case, you can do something like this in the top level CMakeLists.txt:
cmake_minimum_required(VERSION 2.8)
project(test)
include(ExternalProject)
ExternalProject_Add(libantlr
SOURCE_DIR ${CMAKE_CURRENT_SOURCE_DIR}/libantlr
CONFIGURE_COMMAND ${CMAKE_CURRENT_SOURCE_DIR}/libantlr/configure --prefix=<INSTALL_DIR>
BUILD_COMMAND ${MAKE})
The <INSTALL_DIR>
is expanded to something like libantlr-prefix, so things are installed in your build tree rather than in /usr/local, which is what autotools would do without a prefix.
I needed to do something similar but found it surprisingly difficult to get a working solution, despite the example provided here with the accepted answer, and code snippets provided in several other blog posts, the CMake support email listserv archives, etc. For the benefit of others who come across this question, here is my solution.
The external project we wanted to use is libmodbus
, though I believe my solution is general enough to work with any project configured with the standard autoconf
recipe of ./autoconf.sh && configure.sh && make && make install
.
We wanted to add libmodbus
as a submodule of our git repository. We added to our repository at the path <root>/opt/libmodbus
. The CMake
code to configure it is located in <root>/cmake/modbus.cmake
, which is included from our root CMakeLists.txt
using
# libmodbus
include(cmake/modbus.cmake)
The content of cmake/modbus.cmake
is:
include(ExternalProject)
set(MODBUS_DIR ${CMAKE_CURRENT_SOURCE_DIR}/opt/libmodbus)
set(MODBUS_BIN ${CMAKE_CURRENT_BINARY_DIR}/libmodbus)
set(MODBUS_STATIC_LIB ${MODBUS_BIN}/lib/libmodbus.a)
set(MODBUS_INCLUDES ${MODBUS_BIN}/include)
file(MAKE_DIRECTORY ${MODBUS_INCLUDES})
ExternalProject_Add(
libmodbus
PREFIX ${MODBUS_BIN}
SOURCE_DIR ${MODBUS_DIR}
DOWNLOAD_COMMAND cd ${MODBUS_DIR} && git clean -dfX && ${MODBUS_DIR}/autogen.sh
CONFIGURE_COMMAND ${MODBUS_DIR}/configure --srcdir=${MODBUS_DIR} --prefix=${MODBUS_BIN} --enable-static=yes --disable-shared
BUILD_COMMAND make
INSTALL_COMMAND make install
BUILD_BYPRODUCTS ${MODBUS_STATIC_LIB}
)
add_library(modbus STATIC IMPORTED GLOBAL)
add_dependencies(modbus libmodbus)
set_target_properties(modbus PROPERTIES IMPORTED_LOCATION ${MODBUS_STATIC_LIB})
set_target_properties(modbus PROPERTIES INTERFACE_INCLUDE_DIRECTORIES ${MODBUS_INCLUDES})
A component that uses libmodbus
can declare its dependency as usual:
add_executable(hello_modbus main.cpp)
target_link_libraries(hello_modbus modbus)
A few notes:
- This abuses the
DOWNLOAD_COMMAND
to perform theautogen.sh
step. Thegit clean -dfX
is probably not necessary (it is a leftover from an earlier version that used theBUILD_IN_SOURCE
option. If you really want to download the code instead of using a git submodule, you'll need to modify this line appropriately. - We go to the trouble to force a static-only build of the library. Adjust your
configure
command line if you want shared libraries. - The
set_target_properties
command to set theIMPORTED_LOCATION
will fail without theBUILD_BYPRODUCTS ${MODBUS_STATIC_LIB}
declaration. - Likewise, the
set_target_properties
command to set theINTERFACE_INCLUDE_DIRECTORIES
will fail without thefile(MAKE_DIRECTORY ${MODBUS_INCLUDES})
.