Re: [Qemu-devel] [PATCH V9 5/8] libqblock build system

[Paolo Bonzini <pbonzini@redhat.com>]

Il 16/11/2012 11:12, Wenchao Xia ha scritto:
>   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.
>   For testing, make check-libqblock will build binaries and execute it, make
> clean or make check-clean will delete generated binaries.
>   By default this library will be built and tested, out of tree building is
> supported.
>   Header files added in configure due to install-libqblock from out of tree
> build need these them.

Use $(SRC_PATH) instead in the install rules.

> 
> Signed-off-by: Wenchao Xia <xiawenc@linux.vnet.ibm.com>
> ---
>  .gitignore                        |    2 +
>  Makefile                          |   12 ++++++-
>  configure                         |    4 ++-
>  libqblock/Makefile                |   72 +++++++++++++++++++++++++++++++++++++
>  libqblock/libqblock.pc.in         |   13 +++++++
>  tests/Makefile                    |   29 ++++++++++++++-
>  tests/libqblock/libqblock-qcow2.c |    4 ++
>  7 files changed, 133 insertions(+), 3 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-types.h
>  create mode 100644 libqblock/libqblock.c
>  create mode 100644 libqblock/libqblock.h
>  create mode 100644 libqblock/libqblock.pc.in
>  create mode 100644 tests/libqblock/libqblock-qcow2.c
> 
> diff --git a/.gitignore b/.gitignore
> index bd6ba1c..76207fe 100644
> --- a/.gitignore
> +++ b/.gitignore
> @@ -93,3 +93,5 @@ cscope.*
>  tags
>  TAGS
>  *~
> +tests/libqblock/check-*
> +tests/libqblock/test_images
> diff --git a/Makefile b/Makefile
> index 2cde430..4b0755d 100644
> --- a/Makefile
> +++ b/Makefile
> @@ -189,6 +189,16 @@ 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,)
> +
> +install-libqblock:
> +	$(call quiet-command,$(MAKE) $(SUBDIR_MAKEFLAGS) -C libqblock V="$(V)" TARGET_DIR="$*/" install-libqblock,)

Who calls install-libqblock?

> +###########################################################################
> +
>  vscclient$(EXESUF): $(libcacard-y) $(oslib-obj-y) $(trace-obj-y) libcacard/vscclient.o
>  	$(call quiet-command,$(CC) $(LDFLAGS) -o $@ $^ $(libcacard_libs) $(LIBS),"  LINK  $@")
>  
> @@ -230,7 +240,7 @@ clean:
>  	rm -rf qapi-generated
>  	rm -rf qga/qapi-generated
>  	MAKEFILES=./tests/Makefile $(MAKE) check-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/configure b/configure
> index a18e267..b1a1722 100755
> --- a/configure
> +++ b/configure
> @@ -3099,7 +3099,7 @@ tools=""
>  if test "$want_tools" = "yes" ; then
>    tools="qemu-img\$(EXESUF) qemu-io\$(EXESUF) $tools"
>    if [ "$linux" = "yes" -o "$bsd" = "yes" -o "$solaris" = "yes" ] ; then
> -    tools="qemu-nbd\$(EXESUF) $tools"
> +    tools="libqblock.la qemu-nbd\$(EXESUF) $tools"

Why make this conditional?  (Rather, it should be conditional on the
presence of libtool).

Also, perhaps a separate --enable/disable-libqblock switch is better.
It simplifies testing, at least.

>    fi
>  fi
>  if test "$softmmu" = yes ; then
> @@ -4163,12 +4163,14 @@ DIRS="$DIRS pc-bios/optionrom pc-bios/spapr-rtas"
>  DIRS="$DIRS roms/seabios roms/vgabios"
>  DIRS="$DIRS qapi-generated"
>  DIRS="$DIRS libcacard libcacard/libcacard libcacard/trace"
> +DIRS="$DIRS libqblock tests/libqblock"
>  FILES="Makefile tests/Makefile tests/tcg/Makefile qdict-test-data.txt"
>  FILES="$FILES tests/tcg/cris/Makefile tests/tcg/cris/.gdbinit"
>  FILES="$FILES tests/tcg/lm32/Makefile libcacard/Makefile"
>  FILES="$FILES pc-bios/optionrom/Makefile pc-bios/keymaps"
>  FILES="$FILES pc-bios/spapr-rtas/Makefile"
>  FILES="$FILES roms/seabios/Makefile roms/vgabios/Makefile"
> +FILES="$FILES libqblock/Makefile libqblock/libqblock.h libqblock/libqblock-error.h libqblock/libqblock-types.h"

See above.

>  for bios_file in \
>      $source_path/pc-bios/*.bin \
>      $source_path/pc-bios/*.rom \
> diff --git a/libqblock/Makefile b/libqblock/Makefile
> new file mode 100644
> index 0000000..190ffb4
> --- /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)

This should be done by Makefile.objs already.

> +#library objects
> +libqblock-y=libqblock/libqblock.o libqblock/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

Are all of these really needed?  (In fact, after some of the recent
changes none of these should be needed).

> +
> +QEMU_OBJS= $(libqblock-y) $(block-obj-y) $(tools-obj-y)
> +QEMU_OBJS_LIB=$(patsubst %.o, %.lo, $(QEMU_OBJS))
> +
> +QEMU_CFLAGS+= -I$(SRC_PATH) -I$(SRC_PATH)/include -I../
> +#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 libqblock
> +
> +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)$(libqblock_includedir)"
> diff --git a/libqblock/libqblock-error.c b/libqblock/libqblock-error.c
> new file mode 100644
> index 0000000..e69de29
> diff --git a/libqblock/libqblock-error.h b/libqblock/libqblock-error.h
> new file mode 100644
> index 0000000..e69de29
> diff --git a/libqblock/libqblock-types.h b/libqblock/libqblock-types.h
> new file mode 100644
> index 0000000..e69de29
> diff --git a/libqblock/libqblock.c b/libqblock/libqblock.c
> new file mode 100644
> index 0000000..e69de29
> diff --git a/libqblock/libqblock.h b/libqblock/libqblock.h
> new file mode 100644
> index 0000000..e69de29
> diff --git a/libqblock/libqblock.pc.in b/libqblock/libqblock.pc.in
> new file mode 100644
> index 0000000..d2a7d06
> --- /dev/null
> +++ b/libqblock/libqblock.pc.in
> @@ -0,0 +1,13 @@
> +prefix=@PREFIX@
> +exec_prefix=${prefix}
> +libdir=@LIBDIR@
> +includedir=@INCLUDEDIR@
> +
> +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}
> diff --git a/tests/Makefile b/tests/Makefile
> index a286622..ee26ba5 100644
> --- a/tests/Makefile
> +++ b/tests/Makefile
> @@ -84,6 +84,22 @@ check-qtest-$(CONFIG_POSIX)=$(foreach TARGET,$(TARGETS), $(check-qtest-$(TARGET)
>  qtest-obj-y = tests/libqtest.o $(oslib-obj-y)
>  $(check-qtest-y): $(qtest-obj-y)
>  
> +#libqblock test rules
> +
> +LIBQBLOCK_TEST_DIR= tests/libqblock/test_images
> +LIBQBLOCK_DIR = libqblock
> +LIBQBLOCK_SO = $(LIBQBLOCK_DIR)/.libs/libqblock.so
> +LIBQBLOCK_SO_LINK_FLAG= -Wl,-rpath,$(LIBQBLOCK_DIR)/.libs

Not portable.  Please use libtool to link the program:

LTLINK = $(call quiet-command,$(LIBTOOL) --mode=link --quiet --tag=CC
$(CC) $(QEMU_CFLAGS) $(CFLAGS) $(LDFLAGS) -o $@ $(sort $(1)) $(LIBS),"lt
LINK $(TARGET_DIR)$@")

and then

$(check-libqblock-y): %$(EXESUF): %.o
	$(call LTLINK,$^)

> +tests/libqblock/%.o: QEMU_CFLAGS:= $(subst -fPIE,-fPIC, $(QEMU_CFLAGS))
> +tests/libqblock/%.o: QEMU_CFLAGS:= $(subst -DPIE,-DPIC, $(QEMU_CFLAGS))

Why?

A hint: if you have to do something that is not done anywhere else in
the tree, do not do it.

> +tests/libqblock/%.o: QEMU_INCLUDES += -I$(SRC_PATH)/tests -I$(SRC_PATH)/$(LIBQBLOCK_DIR)
> +
> +check-libqblock-y = tests/libqblock/check-libqblock-qcow2$(EXESUF)

Please use something like check-libqblock-$(CONFIG_LIBQBLOCK) so that it
works even if libqblock is not compiled in.

Also, I'm not sure we need a completely separate subdirectory for one
file only.  You can just use

$(check-libqblock-y): QEMU_INCLUDES += ...

Paolo

> +tests/libqblock/check-libqblock-qcow2$(EXESUF): tests/libqblock/libqblock-qcow2.o $(LIBQBLOCK_SO)
> +	$(call quiet-command,$(CC) $(LDFLAGS) -o $@ $^ $(LIBS) $(LIBQBLOCK_SO_LINK_FLAG),"  LINK  $@")
> +
>  .PHONY: check-help
>  check-help:
>  	@echo "Regression testing targets:"
> @@ -94,6 +110,7 @@ check-help:
>  	@echo " make check-unit           Run qobject tests"
>  	@echo " make check-block          Run block tests"
>  	@echo " make check-report.html    Generates an HTML test report"
> +	@echo " make check-libqblock      Run libqblock tests"
>  	@echo " make check-clean          Clean the tests"
>  	@echo
>  	@echo "Please note that HTML reports do not regenerate if the unit tests"
> @@ -126,6 +143,12 @@ $(patsubst %, check-report-qtest-%.xml, $(QTEST_TARGETS)): check-report-qtest-%.
>  check-report-unit.xml: $(check-unit-y)
>  	$(call quiet-command,gtester -q $(GTESTER_OPTIONS) -o $@ -m=$(SPEED) $^, "GTESTER $@")
>  
> +# gtester tests with libqblock
> +
> +.PHONY: $(patsubst %, check-%, $(check-libqblock-y))
> +$(patsubst %, check-%, $(check-libqblock-y)): check-%: %
> +	$(call quiet-command, LIBQBLOCK_TEST_DIR=$(LIBQBLOCK_TEST_DIR) gtester $(GTESTER_OPTIONS) -m=$(SPEED) $*,"GTESTER $*")
> +
>  # Reports and overall runs
>  
>  check-report.xml: $(patsubst %,check-report-qtest-%.xml, $(QTEST_TARGETS)) check-report-unit.xml
> @@ -147,12 +170,16 @@ check-tests/qemu-iotests-quick.sh: tests/qemu-iotests-quick.sh qemu-img$(EXESUF)
>  check-qtest: $(patsubst %,check-qtest-%, $(QTEST_TARGETS))
>  check-unit: $(patsubst %,check-%, $(check-unit-y))
>  check-block: $(patsubst %,check-%, $(check-block-y))
> -check: check-unit check-qtest
> +check-libqblock: $(patsubst %,check-%, $(check-libqblock-y))
> +check: check-unit check-qtest check-libqblock
>  
>  check-clean:
>  	$(MAKE) -C tests/tcg clean
>  	rm -f $(check-unit-y)
>  	rm -f $(check-qtest-i386-y) $(check-qtest-x86_64-y) $(check-qtest-sparc64-y) $(check-qtest-sparc-y)
>  	rm -f tests/*.o
> +	rm -f tests/libqblock/*.o
> +	rm -f $(check-libqblock-y)
> +	rm -rf $(LIBQBLOCK_TEST_DIR)
>  
>  -include $(wildcard tests/*.d)
> diff --git a/tests/libqblock/libqblock-qcow2.c b/tests/libqblock/libqblock-qcow2.c
> new file mode 100644
> index 0000000..c05c0c4
> --- /dev/null
> +++ b/tests/libqblock/libqblock-qcow2.c
> @@ -0,0 +1,4 @@
> +int main(int argc, char **argv)
> +{
> +    return 0;
> +}
>