Add tde_setup_largefiles macro.

The macro sets the necessary definitions so that the default libc
filesystem interface will be for large files on all architectures.

Signed-off-by: Slávek Banko <slavek.banko@axis.cz>

modules/TDEMacros.cmake

@@ -1927,6 +1927,92 @@ macro( tde_setup_msgfmt )
 endmacro( )
 
 
+################################################
+#####
+##### tde_setup_largefiles
+
+macro( tde_setup_largefiles )
+  if( NOT DEFINED HAVE_LARGEFILES )
+    message( STATUS "Check support for large files" )
+    unset( LARGEFILES_DEFINITIONS )
+
+    # check without special definitions
+    unset( HAVE_SIZEOF_T CACHE )
+    check_type_size( off_t SIZEOF_OFF_T )
+    if( SIZEOF_OFF_T GREATER 7 )
+      set( HAVE_LARGEFILES 1 )
+    endif( )
+
+    # check with definition _FILE_OFFSET_BITS=64
+    if( NOT HAVE_LARGEFILES )
+      unset( HAVE_SIZEOF_OFF_T CACHE )
+      tde_save_and_set( CMAKE_REQUIRED_DEFINITIONS "${CMAKE_REQUIRED_DEFINITIONS} -D_FILE_OFFSET_BITS=64" )
+      check_type_size( off_t SIZEOF_OFF_T )
+      tde_restore( CMAKE_REQUIRED_DEFINITIONS )
+      if( SIZEOF_OFF_T GREATER 7 )
+        set( LARGEFILES_DEFINITIONS "-D_FILE_OFFSET_BITS=64" )
+        set( HAVE_LARGEFILES 1 )
+      endif( )
+    endif( )
+
+    # check with definition _LARGE_FILES
+    if( NOT HAVE_LARGEFILES )
+      unset( HAVE_SIZEOF_OFF_T CACHE )
+      tde_save_and_set( CMAKE_REQUIRED_DEFINITIONS "${CMAKE_REQUIRED_DEFINITIONS} -D_LARGE_FILES" )
+      check_type_size( off_t SIZEOF_OFF_T )
+      tde_restore( CMAKE_REQUIRED_DEFINITIONS )
+      if( SIZEOF_OFF_T GREATER 7 )
+        set( LARGEFILES_DEFINITIONS "-D_LARGE_FILES" )
+        set( HAVE_LARGEFILES 1 )
+      endif( )
+    endif( )
+
+    # check with definition _LARGEFILE_SOURCE
+    if( NOT HAVE_LARGEFILES )
+      unset( HAVE_SIZEOF_OFF_T CACHE )
+      tde_save_and_set( CMAKE_REQUIRED_DEFINITIONS "${CMAKE_REQUIRED_DEFINITIONS} -D_LARGEFILE_SOURCE" )
+      check_type_size( off_t SIZEOF_OFF_T )
+      tde_restore( CMAKE_REQUIRED_DEFINITIONS )
+      if( SIZEOF_OFF_T GREATER 7 )
+        set( LARGEFILES_DEFINITIONS "-D_LARGEFILE_SOURCE" )
+        set( HAVE_LARGEFILES 1 )
+      endif( )
+    endif( )
+
+    # check for fseeko/ftello
+    if( HAVE_LARGEFILES )
+      tde_save_and_set( CMAKE_REQUIRED_DEFINITIONS "${CMAKE_REQUIRED_DEFINITIONS} ${LARGEFILES_DEFINITIONS}" )
+      check_symbol_exists( "fseeko" "stdio.h" HAVE_FSEEKO )
+      tde_restore( CMAKE_REQUIRED_DEFINITIONS )
+      if( NOT HAVE_FSEEKO )
+        tde_save_and_set( CMAKE_REQUIRED_DEFINITIONS "${CMAKE_REQUIRED_DEFINITIONS} ${LARGEFILES_DEFINITIONS} -D_LARGEFILE_SOURCE" )
+        check_symbol_exists( "fseeko" "stdio.h" HAVE_FSEEKO )
+        tde_restore( CMAKE_REQUIRED_DEFINITIONS )
+        if( HAVE_FSEEKO )
+          set( LARGEFILES_DEFINITIONS "${LARGEFILES_DEFINITIONS} -D_LARGEFILE_SOURCE" )
+        else( )
+          unset( HAVE_LARGEFILES )
+        endif( )
+      endif( )
+    endif( )
+
+    # check results
+    if( HAVE_LARGEFILES )
+      if( "${LARGEFILES_DEFINITIONS}" STREQUAL "" )
+        message( STATUS "Check support for large files - Success" )
+      else( )
+        add_definitions( ${LARGEFILES_DEFINITIONS} )
+        message( STATUS "Check support for large files - Success with ${LARGEFILES_DEFINITIONS}" )
+      endif( )
+      set( HAVE_LARGEFILES 1 CACHE INTERNAL "Support for large files enabled" )
+    else( )
+      message( STATUS "Check support for large files - Failed" )
+      tde_message_fatal( "Cannot find a way to enable support for large files." )
+    endif( )
+  endif( )
+endmacro( )
+
+
 ################################################
 #####
 ##### Restore CMP0026 policy