# CMake support for large files # # Copyright (C) 2016 Julian Andres Klode <jak@debian.org>. # # Permission is hereby granted, free of charge, to any person # obtaining a copy of this software and associated documentation files # (the "Software"), to deal in the Software without restriction, # including without limitation the rights to use, copy, modify, merge, # publish, distribute, sublicense, and/or sell copies of the Software, # and to permit persons to whom the Software is furnished to do so, # subject to the following conditions: # # The above copyright notice and this permission notice shall be # included in all copies or substantial portions of the Software. # # THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, # EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF # MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND # NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS # BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN # ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN # CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE # SOFTWARE. # # This defines the following variables # # LFS_DEFINITIONS - List of definitions to pass to add_definitions() # LFS_COMPILE_OPTIONS - List of definitions to pass to add_compile_options() # LFS_LIBRARIES - List of libraries and linker flags # LFS_FOUND - If there is Large files support # include(CheckCXXSourceCompiles) include(FindPackageHandleStandardArgs) # Test program to check for LFS. Requires that off_t has at least 8 byte large set(_lfs_test_source " #include <sys/types.h> typedef char my_static_assert[sizeof(off_t) >= 8 ? 1 : -1]; int main(void) { return 0; } " ) # Check if the given options are needed # # This appends to the variables _lfs_cppflags, _lfs_cflags, and _lfs_ldflags, # it also sets LFS_FOUND to 1 if it works. function(_lfs_check_compiler_option var options definitions libraries) set(CMAKE_REQUIRED_QUIET 1) set(CMAKE_REQUIRED_FLAGS ${CMAKE_REQUIRED_FLAGS} ${options}) set(CMAKE_REQUIRED_DEFINITIONS ${CMAKE_REQUIRED_DEFINITIONS} ${definitions}) set(CMAKE_REQUIRED_LIBRARIES ${CMAKE_REQUIRED_DEFINITIONS} ${libraries}) message(STATUS "Looking for LFS support using ${options} ${definitions} ${libraries}") check_cxx_source_compiles("${_lfs_test_source}" ${var}) if(${var}) message(STATUS "Looking for LFS support using ${options} ${definitions} ${libraries} - found") set(_lfs_cppflags ${_lfs_cppflags} ${definitions} PARENT_SCOPE) set(_lfs_cflags ${_lfs_cflags} ${options} PARENT_SCOPE) set(_lfs_ldflags ${_lfs_ldflags} ${libraries} PARENT_SCOPE) set(LFS_FOUND TRUE PARENT_SCOPE) else() message(STATUS "Looking for LFS support using ${options} ${definitions} ${libraries} - not found") endif() endfunction() # Check for the availability of LFS. # The cases handled are: # # * Native LFS # * Output of getconf LFS_CFLAGS; getconf LFS_LIBS; getconf LFS_LDFLAGS # * Preprocessor flag -D_FILE_OFFSET_BITS=64 # * Preprocessor flag -D_LARGE_FILES # function(_lfs_check) set(_lfs_cflags) set(_lfs_cppflags) set(_lfs_ldflags) set(_lfs_libs) set(CMAKE_REQUIRED_QUIET 1) message(STATUS "Looking for native LFS support") check_cxx_source_compiles("${_lfs_test_source}" lfs_native) if (lfs_native) message(STATUS "Looking for native LFS support - found") set(LFS_FOUND TRUE) else() message(STATUS "Looking for native LFS support - not found") endif() if (NOT LFS_FOUND) # Check using getconf. If getconf fails, don't worry, the check in # _lfs_check_compiler_option will fail as well. execute_process(COMMAND getconf LFS_CFLAGS OUTPUT_VARIABLE _lfs_cflags_raw OUTPUT_STRIP_TRAILING_WHITESPACE ERROR_QUIET) execute_process(COMMAND getconf LFS_LIBS OUTPUT_VARIABLE _lfs_libs_tmp OUTPUT_STRIP_TRAILING_WHITESPACE ERROR_QUIET) execute_process(COMMAND getconf LFS_LDFLAGS OUTPUT_VARIABLE _lfs_ldflags_tmp OUTPUT_STRIP_TRAILING_WHITESPACE ERROR_QUIET) separate_arguments(_lfs_cflags_raw) separate_arguments(_lfs_ldflags_tmp) separate_arguments(_lfs_libs_tmp) # Move -D flags to the place they are supposed to be foreach(flag ${_lfs_cflags_raw}) if (flag MATCHES "-D.*") list(APPEND _lfs_cppflags_tmp ${flag}) else() list(APPEND _lfs_cflags_tmp ${flag}) endif() endforeach() # Check if the flags we received (if any) produce working LFS support _lfs_check_compiler_option(lfs_getconf_works "${_lfs_cflags_tmp}" "${_lfs_cppflags_tmp}" "${_lfs_libs_tmp};${_lfs_ldflags_tmp}") endif() if(NOT LFS_FOUND) # IRIX stuff _lfs_check_compiler_option(lfs_need_n32 "-n32" "" "") endif() if(NOT LFS_FOUND) # Linux and friends _lfs_check_compiler_option(lfs_need_file_offset_bits "" "-D_FILE_OFFSET_BITS=64" "") endif() if(NOT LFS_FOUND) # AIX _lfs_check_compiler_option(lfs_need_large_files "" "-D_LARGE_FILES=1" "") endif() set(LFS_DEFINITIONS ${_lfs_cppflags} CACHE STRING "Extra definitions for large file support") set(LFS_COMPILE_OPTIONS ${_lfs_cflags} CACHE STRING "Extra definitions for large file support") set(LFS_LIBRARIES ${_lfs_libs} ${_lfs_ldflags} CACHE STRING "Extra definitions for large file support") set(LFS_FOUND ${LFS_FOUND} CACHE INTERNAL "Found LFS") endfunction() if (NOT LFS_FOUND) _lfs_check() endif() find_package_handle_standard_args(LFS "Could not find LFS. Set LFS_DEFINITIONS, LFS_COMPILE_OPTIONS, LFS_LIBRARIES." LFS_FOUND)