1*e415196aSJoakim Soderberg# - Check if _FILE_OFFSET_BITS macro needed for large files
2*e415196aSJoakim Soderberg# CHECK_FILE_OFFSET_BITS ()
3*e415196aSJoakim Soderberg#
4*e415196aSJoakim Soderberg# The following variables may be set before calling this macro to
5*e415196aSJoakim Soderberg# modify the way the check is run:
6*e415196aSJoakim Soderberg#
7*e415196aSJoakim Soderberg#  CMAKE_REQUIRED_FLAGS = string of compile command line flags
8*e415196aSJoakim Soderberg#  CMAKE_REQUIRED_DEFINITIONS = list of macros to define (-DFOO=bar)
9*e415196aSJoakim Soderberg#  CMAKE_REQUIRED_INCLUDES = list of include directories
10*e415196aSJoakim Soderberg# Copyright (c) 2009, Michihiro NAKAJIMA
11*e415196aSJoakim Soderberg#
12*e415196aSJoakim Soderberg# Redistribution and use is allowed according to the terms of the BSD license.
13*e415196aSJoakim Soderberg# For details see the accompanying COPYING-CMAKE-SCRIPTS file.
14*e415196aSJoakim Soderberg
15*e415196aSJoakim Soderberg#INCLUDE(CheckCSourceCompiles)
16*e415196aSJoakim Soderberg
17*e415196aSJoakim SoderbergGET_FILENAME_COMPONENT(_selfdir_CheckFileOffsetBits
18*e415196aSJoakim Soderberg	 "${CMAKE_CURRENT_LIST_FILE}" PATH)
19*e415196aSJoakim Soderberg
20*e415196aSJoakim SoderbergMACRO (CHECK_FILE_OFFSET_BITS)
21*e415196aSJoakim Soderberg  IF(NOT DEFINED _FILE_OFFSET_BITS)
22*e415196aSJoakim Soderberg    MESSAGE(STATUS "Cheking _FILE_OFFSET_BITS for large files")
23*e415196aSJoakim Soderberg    TRY_COMPILE(__WITHOUT_FILE_OFFSET_BITS_64
24*e415196aSJoakim Soderberg      ${CMAKE_CURRENT_BINARY_DIR}
25*e415196aSJoakim Soderberg      ${_selfdir_CheckFileOffsetBits}/CheckFileOffsetBits.c
26*e415196aSJoakim Soderberg      COMPILE_DEFINITIONS ${CMAKE_REQUIRED_DEFINITIONS})
27*e415196aSJoakim Soderberg    IF(NOT __WITHOUT_FILE_OFFSET_BITS_64)
28*e415196aSJoakim Soderberg      TRY_COMPILE(__WITH_FILE_OFFSET_BITS_64
29*e415196aSJoakim Soderberg        ${CMAKE_CURRENT_BINARY_DIR}
30*e415196aSJoakim Soderberg        ${_selfdir_CheckFileOffsetBits}/CheckFileOffsetBits.c
31*e415196aSJoakim Soderberg        COMPILE_DEFINITIONS ${CMAKE_REQUIRED_DEFINITIONS} -D_FILE_OFFSET_BITS=64)
32*e415196aSJoakim Soderberg    ENDIF(NOT __WITHOUT_FILE_OFFSET_BITS_64)
33*e415196aSJoakim Soderberg
34*e415196aSJoakim Soderberg    IF(NOT __WITHOUT_FILE_OFFSET_BITS_64 AND __WITH_FILE_OFFSET_BITS_64)
35*e415196aSJoakim Soderberg      SET(_FILE_OFFSET_BITS 64 CACHE INTERNAL "_FILE_OFFSET_BITS macro needed for large files")
36*e415196aSJoakim Soderberg      MESSAGE(STATUS "Cheking _FILE_OFFSET_BITS for large files - needed")
37*e415196aSJoakim Soderberg    ELSE(NOT __WITHOUT_FILE_OFFSET_BITS_64 AND __WITH_FILE_OFFSET_BITS_64)
38*e415196aSJoakim Soderberg      SET(_FILE_OFFSET_BITS "" CACHE INTERNAL "_FILE_OFFSET_BITS macro needed for large files")
39*e415196aSJoakim Soderberg      MESSAGE(STATUS "Cheking _FILE_OFFSET_BITS for large files - not needed")
40*e415196aSJoakim Soderberg    ENDIF(NOT __WITHOUT_FILE_OFFSET_BITS_64 AND __WITH_FILE_OFFSET_BITS_64)
41*e415196aSJoakim Soderberg  ENDIF(NOT DEFINED _FILE_OFFSET_BITS)
42*e415196aSJoakim Soderberg
43*e415196aSJoakim SoderbergENDMACRO (CHECK_FILE_OFFSET_BITS)
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