cmake: improve configuration with templates

 - move cmake configuration from mxe-conf to cmake-conf
 - replace `echo` with templates for readability and maintenance
 - allow packages to set other dep files
 - set CMAKE_POLICY_DEFAULT_CMPNNNN in wrapper since
   `cmake_minimum_required` or `cmake_policy` can't be set in
   toolchain (closes #971)

1 files changed, 67 insertions, 0 deletions

diff --git a/src/cmake/conf/mxe-conf.cmake.in b/src/cmake/conf/mxe-conf.cmake.in
new file mode 100644
index 0000000..d9c6a44
--- /dev/null
+++ b/src/cmake/conf/mxe-conf.cmake.in
@@ -0,0 +1,67 @@
+# This file is part of MXE. See LICENSE.md for licensing information.
+
+# https://cmake.org/cmake/help/latest
+
+# Can't set `cmake_minimum_required` or `cmake_policy` in toolchain
+# since toolchain is read before CMakeLists.txt
+# See `target-cmake.in` for CMAKE_POLICY_DEFAULT_CMPNNNN
+
+# Check if we are using mxe supplied version
+#   - toolchain is included multiple times so set a guard in
+#     environment to suppress duplicate messages
+if(NOT ${CMAKE_COMMAND} STREQUAL @PREFIX@/@BUILD@/bin/cmake AND NOT DEFINED ENV{_MXE_CMAKE_TOOLCHAIN_INCLUDED})
+    message(WARNING "
+** Warning: direct use of toolchain file is deprecated
+** Please use prefixed wrapper script instead:
+     @TARGET@-cmake [options] <path-to-source>
+       - uses mxe supplied cmake version @CMAKE_VERSION@
+       - loads toolchain
+       - loads common run results
+       - sets various policy defaults
+    ")
+    set(ENV{_MXE_CMAKE_TOOLCHAIN_INCLUDED} TRUE)
+endif()
+
+## General configuration
+set(CMAKE_SYSTEM_NAME Windows)
+set(MSYS 1)
+set(CMAKE_BUILD_TYPE Release CACHE STRING "Debug|Release|RelWithDebInfo|MinSizeRel" FORCE)
+set(CMAKE_EXPORT_NO_PACKAGE_REGISTRY ON)
+# Workaround for https://www.cmake.org/Bug/view.php?id=14075
+set(CMAKE_CROSS_COMPILING ON)
+
+
+## Library config
+set(BUILD_SHARED_LIBS @CMAKE_SHARED_BOOL@ CACHE BOOL "BUILD_SHARED_LIBS" FORCE)
+set(BUILD_STATIC_LIBS @CMAKE_STATIC_BOOL@ CACHE BOOL "BUILD_STATIC_LIBS" FORCE)
+set(BUILD_SHARED @CMAKE_SHARED_BOOL@ CACHE BOOL "BUILD_SHARED" FORCE)
+set(BUILD_STATIC @CMAKE_STATIC_BOOL@ CACHE BOOL "BUILD_STATIC" FORCE)
+set(LIBTYPE @LIBTYPE@)
+
+
+## Paths etc.
+set(CMAKE_FIND_ROOT_PATH @PREFIX@/@TARGET@)
+set(CMAKE_FIND_ROOT_PATH_MODE_PROGRAM NEVER)
+set(CMAKE_FIND_ROOT_PATH_MODE_INCLUDE ONLY)
+set(CMAKE_FIND_ROOT_PATH_MODE_LIBRARY ONLY)
+set(CMAKE_PREFIX_PATH @PREFIX@/@TARGET@)
+set(CMAKE_INSTALL_PREFIX @PREFIX@/@TARGET@ CACHE PATH "Installation Prefix")
+# For custom mxe FindPackage scripts
+set(CMAKE_MODULE_PATH "@PREFIX@/share/cmake/modules" ${CMAKE_MODULE_PATH})
+
+
+## Programs
+set(CMAKE_C_COMPILER @PREFIX@/bin/@TARGET@-gcc)
+set(CMAKE_CXX_COMPILER @PREFIX@/bin/@TARGET@-g++)
+set(CMAKE_Fortran_COMPILER @PREFIX@/bin/@TARGET@-gfortran)
+set(CMAKE_RC_COMPILER @PREFIX@/bin/@TARGET@-windres)
+# CMAKE_RC_COMPILE_OBJECT is defined in:
+#     <cmake root>/share/cmake-X.Y/Modules/Platform/Windows-windres.cmake
+
+## Individual package configuration
+file(GLOB mxe_cmake_files
+    "@CMAKE_TOOLCHAIN_DIR@/*.cmake"
+)
+foreach(mxe_cmake_file ${mxe_cmake_files})
+    include(${mxe_cmake_file})
+endforeach()