Hi Vegard, I like this idea. With kind regards Thomas > Am 02.01.2016 um 03:31 schrieb Vegard Nossum <vegard.nossum@xxxxxxxxxx>: > > If you don't have libpcap or libvdeplug installed, you will get build > failures when compiling certain files: > > arch/um/drivers/vde_user.c:8:24: fatal error: libvdeplug.h: No such file or directory > #include <libvdeplug.h> > > arch/um/drivers/pcap_user.c:7:18: fatal error: pcap.h: No such file or directory > #include <pcap.h> > > This patch adds a basic pre-build check and defines the kconfig variables > HAVE_LIBPCAP and HAVE_LIBVDEPLUG depending on the result. > > There is a basic disadvantage to this scheme, namely that the user may > never see the options that rely on these libraries if they are not > installed. As a trade-off, we add a brand new option, MISSING_LIBRARIES > (defaulting to 'y'), which allows those options to be visible (and > selectable) anyway. > > [Note: I find this useful personally as I ran into the above build > failures when playing around with UML -- so take this more as a > suggestion on how things MAY be done better than a real patch.] > > Signed-off-by: Vegard Nossum <vegard.nossum@xxxxxxxxxx> > --- > arch/um/Kconfig.common | 18 ++++++++++++++++++ > arch/um/Kconfig.net | 2 ++ > arch/um/Kconfig.um | 13 +++++++++++++ > arch/um/Makefile | 5 +++++ > 4 files changed, 38 insertions(+) > > diff --git a/arch/um/Kconfig.common b/arch/um/Kconfig.common > index d195a87..35ce3a1 100644 > --- a/arch/um/Kconfig.common > +++ b/arch/um/Kconfig.common > @@ -59,3 +59,21 @@ config HZ > config SUBARCH > string > option env="SUBARCH" > + > +# Host libraries; these are defined by arch/um/Makefile > + > +config ENV_HAVE_LIBPCAP > + string > + option env="ENV_HAVE_LIBPCAP" > + > +config HAVE_LIBPCAP > + bool > + default y if ENV_HAVE_LIBPCAP="1" > + > +config ENV_HAVE_LIBVDEPLUG > + string > + option env="ENV_HAVE_LIBVDEPLUG" > + > +config HAVE_LIBVDEPLUG > + bool > + default y if ENV_HAVE_LIBVDEPLUG="1" > diff --git a/arch/um/Kconfig.net b/arch/um/Kconfig.net > index 820a56f..dfa7849 100644 > --- a/arch/um/Kconfig.net > +++ b/arch/um/Kconfig.net > @@ -111,6 +111,7 @@ config UML_NET_DAEMON > config UML_NET_VDE > bool "VDE transport" > depends on UML_NET > + depends on HAVE_LIBVDEPLUG || MISSING_LIBRARIES > help > This User-Mode Linux network transport allows one or more running > UMLs on a single host to communicate with each other and also > @@ -158,6 +159,7 @@ config UML_NET_MCAST > config UML_NET_PCAP > bool "pcap transport" > depends on UML_NET > + depends on HAVE_LIBPCAP || MISSING_LIBRARIES > help > The pcap transport makes a pcap packet stream on the host look > like an ethernet device inside UML. This is useful for making > diff --git a/arch/um/Kconfig.um b/arch/um/Kconfig.um > index 28a9885..15944d9 100644 > --- a/arch/um/Kconfig.um > +++ b/arch/um/Kconfig.um > @@ -9,6 +9,19 @@ config STATIC_LINK > Additionally, this option enables using higher memory spaces (up to > 2.75G) for UML. > > +config MISSING_LIBRARIES > + bool "Prompt for options which require missing host libraries" > + default y > + help > + Certain options rely on host libraries to compile. > + > + If you say N here, then these options will only be available if > + the libraries they require have been detected to be present. > + > + If you say Y, then the options will be available anyway, but > + beware that attempting to build the kernel will most likely > + result in an error. > + > source "mm/Kconfig" > > config LD_SCRIPT_STATIC > diff --git a/arch/um/Makefile b/arch/um/Makefile > index e3abe6f..a8320e6 100644 > --- a/arch/um/Makefile > +++ b/arch/um/Makefile > @@ -166,3 +166,8 @@ include/generated/user_constants.h: $(HOST_DIR)/um/user-offsets.s > $(call filechk,gen-asm-offsets) > > export SUBARCH USER_CFLAGS CFLAGS_NO_HARDENING OS DEV_NULL_PATH > + > +# Host libraries > +has_header = $(shell echo | $(CC) -include $(1) -xc -c - >/dev/null 2>&1 && echo 1) > +export ENV_HAVE_LIBPCAP := $(call has_header,pcap.h) > +export ENV_HAVE_LIBVDEPLUG := $(call has_header,libvdeplug.h) > -- > 1.9.1 > > > ------------------------------------------------------------------------------ > _______________________________________________ > User-mode-linux-devel mailing list > User-mode-linux-devel@xxxxxxxxxxxxxxxxxxxxx > https://lists.sourceforge.net/lists/listinfo/user-mode-linux-devel -- To unsubscribe from this list: send the line "unsubscribe linux-kbuild" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
