Re: [Qemu-devel] [PATCH V6 1/5] libqblock build system

[wenchao xia]

> On Sun, Oct 7, 2012 at 5:32 AM, Wenchao Xia <address@hidden> wrote:
> > From: Wenchao Xia <address@hidden>
> >
> >    Libqblock was placed in new directory ./libqblock, libtool will build
> > dynamic library there, source files of block layer remains in ./block.
> > So block related source code will generate 3 sets of binary, first is old
> > ones used in qemu, second and third are non PIC and PIC ones in ./libqblock.
> >    GCC compiler flag visibility=hidden was used with special macro, to export
> > only symbols that was marked as PUBLIC.
> >
> > Signed-off-by: Wenchao Xia <address@hidden>
> > ---
> >   Makefile                       |   11 +++++-
> >   libqblock/Makefile             |   72 ++++++++++++++++++++++++++++++++++++++++
> >   libqblock/libqblock.pc.in      |   13 +++++++
> >   3 files changed, 95 insertions(+), 1 deletions(-)
> >   create mode 100644 libqblock/Makefile
> >   create mode 100644 libqblock/libqblock-error.c
> >   create mode 100644 libqblock/libqblock-error.h
> >   create mode 100644 libqblock/libqblock-internal.h
> >   create mode 100644 libqblock/libqblock-types.h
> >   create mode 100644 libqblock/libqblock.c
> >   create mode 100644 libqblock/libqblock.h
> >   create mode 100644 libqblock/libqblock.pc.in
> >
> > diff --git a/Makefile b/Makefile
> > index a9c22bf..53006c1 100644
> > --- a/Makefile
> > +++ b/Makefile
> > @@ -169,6 +169,15 @@ qemu-io$(EXESUF): qemu-io.o cmd.o $(tools-obj-y) 
> > $(block-obj-y)
> >
> >   qemu-bridge-helper$(EXESUF): qemu-bridge-helper.o
> >
> > +######################################################################
> > +# Support building shared library libqblock
> > +libqblock.la:
> > +       $(call quiet-command,$(MAKE) $(SUBDIR_MAKEFLAGS) -C libqblock V="$(V)" 
> > TARGET_DIR="$*/" libqblock.la,)
>
> Does not work for out of tree build:
> $ make -C obj-amd64 libqblock.la
> make: Entering directory `/src/qemu/obj-amd64'
> make: Entering an unknown directory
> make: *** libqblock: No such file or directory.  Stop.
> make: Leaving an unknown directory
> make: *** [libqblock.la] Error 2
> make: Leaving directory `/src/qemu/obj-amd64'
>
> If I fake what 'configure' should be doing and add the directory and
> link to Makefile, there are still problems:
> $ make -C obj-amd64 libqblock.la
> make: Entering directory `/src/qemu/obj-amd64'
> make[1]: *** No rule to make target `libqblock.lo', needed by
> `libqblock.la'.  Stop.
> make: *** [libqblock.la] Error 2
  Could u give more tip about this error? what is obj-amd64?
My understanding is you tried to build the library from another
directory similar as:
/extend_disk/xiawenc/qemu/qemu have the qemu source code, then
address@hidden xiawenc]$ pwd
/extend_disk/xiawenc
address@hidden xiawenc]$ make -C qemu/qemu libqblock.la
failed.
Please correct me.

> I think the library should be built by default, like vscclient which
> probably nobody uses.
  libvirt can't link to it now for OOM issue, but I will wrapper the
APIs with RPC later.

> > +
> > +install-libqblock:
> > +       $(call quiet-command,$(MAKE) $(SUBDIR_MAKEFLAGS) -C libqblock V="$(V)" 
> > TARGET_DIR="$*/" install-libqblock,)
> > +###########################################################################
> > +
> >   vscclient$(EXESUF): $(libcacard-y) $(oslib-obj-y) $(trace-obj-y) 
> > $(tools-obj-y) qemu-timer-common.o libcacard/vscclient.o
> >          $(call quiet-command,$(CC) $(LDFLAGS) -o $@ $^ $(libcacard_libs) $(LIBS),"  
> > LINK  $@")
> >
> > @@ -232,7 +241,7 @@ clean:
> >          rm -rf qapi-generated
> >          rm -rf qga/qapi-generated
> >          $(MAKE) -C tests/tcg clean
> > -       for d in $(ALL_SUBDIRS) $(QEMULIBS) libcacard; do \
> > +       for d in $(ALL_SUBDIRS) $(QEMULIBS) libcacard libqblock; do \
> >          if test -d $$d; then $(MAKE) -C $$d $@ || exit 1; fi; \
> >          rm -f $$d/qemu-options.def; \
> >           done
> > diff --git a/libqblock/Makefile b/libqblock/Makefile
> > new file mode 100644
> > index 0000000..cd5f4c1
> > --- /dev/null
> > +++ b/libqblock/Makefile
> > @@ -0,0 +1,72 @@
> > +###########################################################################
> > +# libqblock Makefile
> > +# Todo:
> > +#    1 trace related files is generated in this directory, move
> > +#  them to the root directory.
> > +##########################################################################
> > +-include ../config-host.mak
> > +-include $(SRC_PATH)/Makefile.objs
> > +-include $(SRC_PATH)/rules.mak
> > +
> > +#############################################################################
> > +# Library settings
> > +#############################################################################
> > +$(call set-vpath, $(SRC_PATH))
> > +
> > +#expand the foldered vars,especially ./block
> > +dummy := $(call unnest-vars)
> > +
> > +#library objects
> > +libqblock-y=libqblock.o libqblock-error.o
> > +tools-obj-y =  $(oslib-obj-y) $(trace-obj-y) qemu-tool.o qemu-timer.o \
> > +       qemu-timer-common.o main-loop.o notify.o \
> > +       iohandler.o cutils.o iov.o async.o
> > +tools-obj-$(CONFIG_POSIX) += compatfd.o
> > +
> > +
> > +QEMU_OBJS= $(libqblock-y) $(block-obj-y) $(tools-obj-y)
> > +QEMU_OBJS_LIB=$(patsubst %.o, %.lo, $(QEMU_OBJS))
> > +
> > +QEMU_CFLAGS+= -I../ -I../include
> > +#adding magic macro define for symbol hiding and exposing
> > +QEMU_CFLAGS+= -fvisibility=hidden -D LIBQB_BUILD
> > +
> > +#dependency libraries
> > +LIBS+=-lz $(LIBS_TOOLS)
> > +
> > +#header files to be installed
> > +libqblock-pub-headers=libqblock.h libqblock-types.h libqblock-error.h
> > +libqblock_includedir=$(includedir)/qblock
> > +libqblock_srcpath=$(SRC_PATH)/libqblock
> > +
> > +#################################################################
> > +# Runtime rules
> > +#################################################################
> > +clean:
> > +       rm -f *.lo *.o *.d *.la libqblock-test trace.c trace.c-timestamp *.pc
> > +       rm -rf .libs block trace audio fsdev hw net qapi qga qom slirp ui
> > +
> > +all: libqblock.la libqblock.pc
> > +# Dummy command so that make thinks it has done something
> > +       @true
> > +
> > +libqblock.la: $(QEMU_OBJS_LIB)
> > +       $(call quiet-command,$(LIBTOOL) --mode=link --quiet --tag=CC $(CC) -rpath 
> > $(libdir) -o $@ $^ $(LIBS),"  lt LINK $@")
> > +
> > +libqblock.pc: $(libqblock_srcpath)/libqblock.pc.in
> > +       $(call quiet-command,sed -e 's|@LIBDIR@|$(libdir)|' \
> > +               -e 's|@INCLUDEDIR@|$(libqblock_includedir)|' \
> > +           -e 's|@VERSION@|$(shell cat $(SRC_PATH)/VERSION)|' \
> > +               -e 's|@PREFIX@|$(prefix)|' \
> > +               < $(libqblock_srcpath)/libqblock.pc.in > libqblock.pc,\
> > +       "  GEN   $@")
> > +
> > +.PHONY: install-libqblock
> > +
> > +install-libqblock: libqblock.la libqblock.pc
> > +       $(INSTALL_DIR) "$(DESTDIR)$(libdir)"
> > +       $(INSTALL_DIR) "$(DESTDIR)$(libdir)/pkgconfig"
> > +       $(INSTALL_DIR) "$(DESTDIR)$(libqblock_includedir)"
> > +       $(LIBTOOL) --mode=install $(INSTALL_DATA) libqblock.la 
> > "$(DESTDIR)$(libdir)"
> > +       $(LIBTOOL) --mode=install $(INSTALL_DATA) libqblock.pc 
> > "$(DESTDIR)$(libdir)/pkgconfig"
> > +       $(LIBTOOL) --mode=install $(INSTALL_DATA) $(libqblock-pub-headers) 
> > "$(DESTDIR)$(libqblock_includedir)"
> > diff --git a/libqblock/libqblock-error.c b/libqblock/libqblock-error.c
> > new file mode 100644
> > index 0000000..e69de29
> > diff --git a/libqblock/libqblock-error.h b/libqblock/libqblock-error.h
> > new file mode 100644
> > index 0000000..e69de29
> > diff --git a/libqblock/libqblock-internal.h b/libqblock/libqblock-internal.h
> > new file mode 100644
> > index 0000000..e69de29
> > diff --git a/libqblock/libqblock-types.h b/libqblock/libqblock-types.h
> > new file mode 100644
> > index 0000000..e69de29
> > diff --git a/libqblock/libqblock.c b/libqblock/libqblock.c
> > new file mode 100644
> > index 0000000..e69de29
> > diff --git a/libqblock/libqblock.h b/libqblock/libqblock.h
> > new file mode 100644
> > index 0000000..e69de29
> > diff --git a/libqblock/libqblock.pc.in b/libqblock/libqblock.pc.in
> > new file mode 100644
> > index 0000000..d2a7d06
> > --- /dev/null
> > +++ b/libqblock/libqblock.pc.in
> > @@ -0,0 +1,13 @@
> > address@hidden@
> > +exec_prefix=${prefix}
> > address@hidden@
> > address@hidden@
> > +
> > +Name: qblock
> > +Description: QEMU block layer library
> > +Version: @VERSION@
> > +
> > +Requires:  rt gthread-2.0 glib-2.0 z curl cap-ng uuid
> > +Libs: -L${libdir} -lqblock
> > +Libs.private:
> > +Cflags: -I${includedir}
> > --
> > 1.7.1