#============================================================================
# Rules for specifying compiler and linker flags
#============================================================================

##  LinkWith target : libs [ : options ]
##    Link a target with libraries. The specified libraries should have
##    build rules in the same project. For external libraries use the
##    ExternalLibs rule. Specify the library names without any extensions or
##    the leading "lib".
rule LinkWith
{
    local i libs sharedlib ;

    for i in $(>) {
        if $($(i)_TYPE) = "library" {
            if [ IsElem shared : $($(i)_OPTIONS) ] {
                libs += $(i) ;
                sharedlib = true ;
            } else {
                # for non shared libs add inherit the compile flags and libs
                libs += $(i) $($(i)_LIBRARIES) ;
                # inherit the exported flags
                CppFlags $(<) : $($(i)_CPPFLAGS) : $(3) ;
                CFlags $(<) : $($(i)_CFLAGS) : $(3) ;
                C++Flags $(<) : $($(i)_C++FLAGS) : $(3) ;
                LFlags $(<) : $($(i)_LFLAGS) : $(3) ;
            }
        } else {
            echo "WARNING: Trying to link" $(i)
                "with" $(<) "which is not a library." ;
        }
    }
    # resolve library dependencies
    libs = [ RemoveDups $(libs) ] ;    
    $(<)_LIBRARIES = $(libs) ;

    local libfiles ;
    for i in $(libs) {
        libfiles += $($(i)_TARGET) ;
    }

    DEPENDS $($(<)_TARGET) : $(libfiles) ;
    NEEDLIBS on $($(<)_TARGET) += $(libfiles) ;
    # the usual libtool hack...
    if $(sharedlib) {
        LINK on $($(<)_TARGET) = "$(LIBTOOL) $(LINK)" ;
        INSTALL on $($(<)_INSTALLTARGET) = "$(LIBTOOL) --mode=install $(INSTALL)" ;
    }
}

rule CppFlags
{
    CPPFLAGS on $($(<)_OBJECTS) += $(>) ;

    if [ IsElem export : $(3) ] {
	$(<)_CPPFLAGS = $(>) ;
    }
}

##  CFlags target : flags [ : options ]
##    Sets cflags on all sourcefiles of a target
##    This rule affects c++ and c compiler flags. Options:
##      export - export the cflags to dependent targets (for example in
##              a library context this will inherit the cflags to the apps using
##              the library)
rule CFlags
{
    CFLAGS on $($(<)_OBJECTS) += $(>) ;

    if [ IsElem export : $(3) ] {
        $(<)_CFLAGS = $(>) ;
    }
}

rule C++Flags
{
    C++FLAGS on $($(<)_OBJECTS) += $(>) ;

    if [ IsElem export : $(3) ] {
	$(<)_C++FLAGS = $(>) ;
    }
}

##  LFlags target : flags [ : options ]
##    Sets linker flags for a library, plugin or application target
rule LFlags
{
    LFLAGS on $($(<)_TARGET) += $(>) ;

    if [ IsElem export : $(3) ] {
        $(<)_LFLAGS = $(>) ;
    }
}

##  ExternalLibs appname : linkerflags [ : options ]
##    Link an application/library/plugin with external libraries. It is
##    possible to give a set of flags which will be passed to the linker when
##    building the application (typically -L and -l flags).
rule ExternalLibs
{
    local i ;
  
    for i in $(>)
    {
        CppFlags $(<) : $($(i)_CFLAGS) : $(3) ;
        LFlags $(<) : $($(i)_LIBS) : $(3) ;
    }
}

##  ExtraObjects target : objectfiles
##    Link additional object files with a target
rule ExtraObjects
{
    EXTRAOBJECTS on $($(<)_TARGET) += $(>) ;
    Depends $($(<)_TARGET) : $(>) ;
    Clean $(<)clean : $(>) ;
    Clean clean : $(>) ;
}

##  IncludeDir [target : ] directories
##    Description: Is used to specify the location of header files for a
##    target or the whole project if no target is given.
##    This rule will automatically generate the -I compiler flags and makes
##    sure the dependency scanner is able to locate your header files. The
##    directories are relative to the current subdir specified with the SubDir
##    rule.
##    Implementation: The directories are simply added to the HDRSEARCH variable
##    which is respected by all jam rules.
rule IncludeDir
{
    local dir i ;
    
    if $(>) {
        for i in $(>) {
            dir = [ ConcatDirs $(SUBDIR) $(i) ] ;
            CppFlags $(<) : [ CreateIncludeFlags $(dir) ] ;

            # needed for header scanning
            HDRSEARCH on $($(<)_SOURCES) += $(dir) ;
        }
    } else {
        for i in $(<) {
            dir = [ ConcatDirs $(SUBDIR) $(i) ] ;
            CPPFLAGS += [ CreateIncludeFlags $(dir) ] ;
            # needed for header scanning
            HDRSEARCH += $(dir) ;
        }
    }
}

rule DefineConst
{
    if $(>) {
        CppFlags $(<) : [ CreateDefineFlags $(>) ] ;
    } else {
        CPPFLAGS += [ CreateDefineFlags $(<) ] ;
    }
}