openjpeg/cmake/TestLargeFiles.cmake

135 lines
5.4 KiB
CMake

# - Define macro to check large file support
#
# OPJ_TEST_LARGE_FILES(VARIABLE)
#
# VARIABLE will be set to true if off_t is 64 bits, and fseeko/ftello present.
# This macro will also defines the necessary variable enable large file support, for instance
# _LARGE_FILES
# _LARGEFILE_SOURCE
# _FILE_OFFSET_BITS 64
# HAVE_FSEEKO
#
# However, it is YOUR job to make sure these defines are set in a #cmakedefine so they
# end up in a config.h file that is included in your source if necessary!
#
# Adapted from Gromacs project (http://www.gromacs.org/)
# by Julien Malik
#
macro(OPJ_TEST_LARGE_FILES VARIABLE)
if("${VARIABLE}" MATCHES "^${VARIABLE}$")
# On most platforms it is probably overkill to first test the flags for 64-bit off_t,
# and then separately fseeko. However, in the future we might have 128-bit filesystems
# (ZFS), so it might be dangerous to indiscriminately set e.g. _FILE_OFFSET_BITS=64.
message(STATUS "Checking for 64-bit off_t")
# First check without any special flags
try_compile(FILE64_OK "${PROJECT_BINARY_DIR}"
"${PROJECT_SOURCE_DIR}/cmake/TestFileOffsetBits.c")
if(FILE64_OK)
message(STATUS "Checking for 64-bit off_t - present")
endif()
if(NOT FILE64_OK)
# Test with _FILE_OFFSET_BITS=64
try_compile(FILE64_OK "${PROJECT_BINARY_DIR}"
"${PROJECT_SOURCE_DIR}/cmake/TestFileOffsetBits.c"
COMPILE_DEFINITIONS "-D_FILE_OFFSET_BITS=64" )
if(FILE64_OK)
message(STATUS "Checking for 64-bit off_t - present with _FILE_OFFSET_BITS=64")
set(_FILE_OFFSET_BITS 64)
endif()
endif()
if(NOT FILE64_OK)
# Test with _LARGE_FILES
try_compile(FILE64_OK "${PROJECT_BINARY_DIR}"
"${PROJECT_SOURCE_DIR}/cmake/TestFileOffsetBits.c"
COMPILE_DEFINITIONS "-D_LARGE_FILES" )
if(FILE64_OK)
message(STATUS "Checking for 64-bit off_t - present with _LARGE_FILES")
set(_LARGE_FILES 1)
endif()
endif()
if(NOT FILE64_OK)
# Test with _LARGEFILE_SOURCE
try_compile(FILE64_OK "${PROJECT_BINARY_DIR}"
"${PROJECT_SOURCE_DIR}/cmake/TestFileOffsetBits.c"
COMPILE_DEFINITIONS "-D_LARGEFILE_SOURCE" )
if(FILE64_OK)
message(STATUS "Checking for 64-bit off_t - present with _LARGEFILE_SOURCE")
set(_LARGEFILE_SOURCE 1)
endif()
endif()
#if(NOT FILE64_OK)
# # now check for Windows stuff
# try_compile(FILE64_OK "${PROJECT_BINARY_DIR}"
# "${PROJECT_SOURCE_DIR}/cmake/TestWindowsFSeek.c")
# if(FILE64_OK)
# message(STATUS "Checking for 64-bit off_t - present with _fseeki64")
# set(HAVE__FSEEKI64 1)
# endif()
#endif()
if(NOT FILE64_OK)
message(STATUS "Checking for 64-bit off_t - not present")
endif()
set(_FILE_OFFSET_BITS ${_FILE_OFFSET_BITS} CACHE INTERNAL "Result of test for needed _FILE_OFFSET_BITS=64")
set(_LARGE_FILES ${_LARGE_FILES} CACHE INTERNAL "Result of test for needed _LARGE_FILES")
set(_LARGEFILE_SOURCE ${_LARGEFILE_SOURCE} CACHE INTERNAL "Result of test for needed _LARGEFILE_SOURCE")
# Set the flags we might have determined to be required above
configure_file("${PROJECT_SOURCE_DIR}/cmake/TestLargeFiles.c.cmake.in"
"${PROJECT_BINARY_DIR}${CMAKE_FILES_DIRECTORY}/TestLargeFiles.c")
message(STATUS "Checking for fseeko/ftello")
# Test if ftello/fseeko are available
try_compile(FSEEKO_COMPILE_OK
"${PROJECT_BINARY_DIR}"
"${PROJECT_BINARY_DIR}${CMAKE_FILES_DIRECTORY}/TestLargeFiles.c")
if(FSEEKO_COMPILE_OK)
message(STATUS "Checking for fseeko/ftello - present")
endif()
if(NOT FSEEKO_COMPILE_OK)
# glibc 2.2 needs _LARGEFILE_SOURCE for fseeko (but not for 64-bit off_t...)
try_compile(FSEEKO_COMPILE_OK
"${PROJECT_BINARY_DIR}"
"${PROJECT_BINARY_DIR}${CMAKE_FILES_DIRECTORY}/TestLargeFiles.c"
COMPILE_DEFINITIONS "-D_LARGEFILE_SOURCE" )
if(FSEEKO_COMPILE_OK)
message(STATUS "Checking for fseeko/ftello - present with _LARGEFILE_SOURCE")
set(_LARGEFILE_SOURCE ${_LARGEFILE_SOURCE} CACHE INTERNAL "Result of test for needed _LARGEFILE_SOURCE")
endif()
endif()
if(FSEEKO_COMPILE_OK)
set(HAVE_FSEEKO ON CACHE INTERNAL "Result of test for fseeko/ftello")
else()
message(STATUS "Checking for fseeko/ftello - not found")
set(HAVE_FSEEKO OFF CACHE INTERNAL "Result of test for fseeko/ftello")
endif()
if(FILE64_OK AND FSEEKO_COMPILE_OK)
message(STATUS "Large File support - found")
set(${VARIABLE} ON CACHE INTERNAL "Result of test for large file support")
else()
message(STATUS "Large File support - not found")
set(${VARIABLE} OFF CACHE INTERNAL "Result of test for large file support")
endif()
endif()
endmacro()