tools: link each shared library or binary only against the libraries it uses

In particular if binary A uses libB and libB uses libC entirely
internally then A does not need to link against libC only libB.

However when linking binary A the linker does need to have visibility
of the libraries which libB links against (libC in this example). For
out of tree uses this is achieved without fuss due because the
libraries are installed in a standard path. However in the case of
in-tree users the linker needs a hint in the form of the -rpath-link
option.  Therefore a new class of build variable, $(SHLIB_FOO), is
introduced which includes the linker options needed to link against a
library which uses libFOO. The intention is that $(LDLIBS_bar) will
include the $(SHLIB_foo)s which it uses where necessary rather
requiring that users are aware of this.

For the python extensions this change appears particularly large since
previously each of python bindings were linked against the union of
all possible libraries used by all bindings instead of just what they
individually needed.

This change removes a dependency on libdl.so from nearly everything
in the system, only libxenctrl actually uses it.

In the context of xl/libxl the intention of libxl is to remove any
need for a user of libxl to know about libxenstore or libxenctrl,
however in the current build it is xl which links against those
libraries rather than libxl (which only links against libc). After
this change libxl correctly depends on the libraries it uses and xl
does not depend on libraries which it is not support to be required to
know about. Note that xl does depend on libxenctrl.so since it uses
xtl_* directly.

Signed-off-by: Ian Campbell <ian.campbell@citrix.com>
Committed-by: Ian Jackson <ian.jackson@eu.citrix.com>

diff --git a/tools/Rules.mk b/tools/Rules.mk
index f7dda356b5c5c82bad110c6f6bf0da5c545f824c..6249573c5bcb1dafd5bbe4dadf9685feb2c21603 100644 (file)
--- a/tools/Rules.mk
+++ b/tools/Rules.mk
@@ -11,6 +11,7 @@ INSTALL = $(XEN_ROOT)/tools/cross-install
 XEN_INCLUDE        = $(XEN_ROOT)/tools/include
 XEN_XC             = $(XEN_ROOT)/tools/python/xen/lowlevel/xc
 XEN_LIBXC          = $(XEN_ROOT)/tools/libxc
+XEN_XENLIGHT       = $(XEN_ROOT)/tools/libxl
 XEN_XENSTORE       = $(XEN_ROOT)/tools/xenstore
 XEN_LIBXENSTAT     = $(XEN_ROOT)/tools/xenstat/libxenstat/src
 XEN_BLKTAP2        = $(XEN_ROOT)/tools/blktap2
@@ -18,13 +19,16 @@ XEN_BLKTAP2        = $(XEN_ROOT)/tools/blktap2
 CFLAGS_include = -I$(XEN_INCLUDE)
 
 CFLAGS_libxenctrl = -I$(XEN_LIBXC) $(CFLAGS_include)
-LDLIBS_libxenctrl = -L$(XEN_LIBXC) -lxenctrl $(DLOPEN_LIBS)
+LDLIBS_libxenctrl = -L$(XEN_LIBXC) -lxenctrl
+SHLIB_libxenctrl  = -Wl,-rpath-link=$(XEN_LIBXC)
 
 CFLAGS_libxenguest = -I$(XEN_LIBXC) $(CFLAGS_include)
 LDLIBS_libxenguest = -L$(XEN_LIBXC) -lxenguest
+SHLIB_libxenguest  = -Wl,-rpath-link=L$(XEN_LIBXC)
 
 CFLAGS_libxenstore = -I$(XEN_XENSTORE) $(CFLAGS_include)
 LDLIBS_libxenstore = -L$(XEN_XENSTORE) -lxenstore
+SHLIB_libxenstore  = -Wl,-rpath-link=$(XEN_XENSTORE)
 
 ifeq ($(CONFIG_Linux),y)
 LIBXL_BLKTAP = y
@@ -35,11 +39,17 @@ endif
 ifeq ($(LIBXL_BLKTAP),y)
 CFLAGS_libblktapctl = -I$(XEN_BLKTAP2)/control -I$(XEN_BLKTAP2)/include $(CFLAGS_include)
 LDLIBS_libblktapctl = -L$(XEN_BLKTAP2)/control -lblktapctl
+SHLIB_libblktapctl  = -Wl,-rpath-link=$(XEN_BLKTAP2)/control
 else
 CFLAGS_libblktapctl =
 LDLIBS_libblktapctl =
+SHLIB_libblktapctl  =
 endif
 
+CFLAGS_libxenlight = -I$(XEN_XENLIGHT) $(CFLAGS_include)
+LDLIBS_libxenlight = -L$(XEN_XENLIGHT) $(SHLIB_libxenctrl) $(SHLIB_libxenstore) $(SHLIB_libblktapctl) -lxenlight
+SHLIB_libxenlight  = -Wl,-rpath-link=$(XEN_XENLIGHT)
+
 X11_LDPATH = -L/usr/X11R6/$(LIBLEAFDIR)
 
 CFLAGS += -D__XEN_TOOLS__

diff --git a/tools/blktap2/drivers/Makefile b/tools/blktap2/drivers/Makefile
index b718c0839fef609a685bc3447403e75b4660d4fa..33a33d36065d13f63d3edb996b0f3bf7f1cf2b67 100644 (file)
--- a/tools/blktap2/drivers/Makefile
+++ b/tools/blktap2/drivers/Makefile
@@ -29,10 +29,6 @@ LBLIBS_img := $(LDLIBS_libxenctrl) $(CRYPT_LIB) -lpthread -lz -lm
 
 LIBS += -L$(LIBVHDDIR) -lvhd
 
-ifeq ($(CONFIG_Linux),y)
-LIBS += -luuid
-endif
-
 REMUS-OBJS  := block-remus.o
 REMUS-OBJS  += hashtable.o
 REMUS-OBJS  += hashtable_itr.o

diff --git a/tools/blktap2/vhd/Makefile b/tools/blktap2/vhd/Makefile
index cb5e14593ddc2ab69a5f538855136d40cb94b701..1dcf9a549253efdfe4a8a40552fd53b0dac36499 100644 (file)
--- a/tools/blktap2/vhd/Makefile
+++ b/tools/blktap2/vhd/Makefile
@@ -22,9 +22,6 @@ CFLAGS            += -static
 endif
 
 LIBS              := -Llib -lvhd
-ifeq ($(CONFIG_Linux),y)
-LIBS              += -luuid
-endif
 
 # Get gcc to generate the dependencies for us.
 CFLAGS            += -Wp,-MD,.$(@F).d

diff --git a/tools/libxl/Makefile b/tools/libxl/Makefile
index 725d5d1491b5c53957e45096b3764c51cd2311ea..62020ed31b09c0b5335a20cd554d71d82bf4107a 100644 (file)
--- a/tools/libxl/Makefile
+++ b/tools/libxl/Makefile
@@ -15,11 +15,17 @@ CFLAGS += -Werror -Wno-format-zero-length -Wmissing-declarations
 CFLAGS += -I. -fPIC
 CFLAGS += $(CFLAGS_libxenctrl) $(CFLAGS_libxenguest) $(CFLAGS_libxenstore) $(CFLAGS_libblktapctl)
 
-LIBS = $(LDLIBS_libxenctrl) $(LDLIBS_libxenguest) $(LDLIBS_libxenstore) $(LDLIBS_libblktapctl) $(UTIL_LIBS)
 ifeq ($(CONFIG_Linux),y)
-LIBS += -luuid
+LIBUUID_LIBS += -luuid
 endif
 
+LIBXL_LIBS =
+LIBXL_LIBS = $(LDLIBS_libxenctrl) $(LDLIBS_libxenguest) $(LDLIBS_libxenstore) $(LDLIBS_libblktapctl) $(UTIL_LIBS) $(LIBUUID_LIBS)
+
+LIBXLU_LIBS =
+
+CLIENT_LIBS = $(LDLIBS_libxenlight)
+
 LIBXL_OBJS-y = osdeps.o libxl_paths.o libxl_bootloader.o flexarray.o
 ifeq ($(LIBXL_BLKTAP),y)
 LIBXL_OBJS-y += libxl_blktap2.o
@@ -81,7 +87,7 @@ libxenlight.so.$(MAJOR): libxenlight.so.$(MAJOR).$(MINOR)
        ln -sf $< $@
 
 libxenlight.so.$(MAJOR).$(MINOR): $(LIBXL_OBJS)
-       $(CC) $(CFLAGS) $(LDFLAGS) -Wl,$(SONAME_LDFLAG) -Wl,libxenlight.so.$(MAJOR) $(SHLIB_LDFLAGS) -o $@ $^
+       $(CC) $(CFLAGS) -Wl,-rpath-link -Wl,$(XEN_ROOT)/tools/libxc $(LDFLAGS) -Wl,$(SONAME_LDFLAG) -Wl,libxenlight.so.$(MAJOR) $(SHLIB_LDFLAGS) -o $@ $^ $(LIBXL_LIBS)
 
 libxenlight.a: $(LIBXL_OBJS)
        $(AR) rcs libxenlight.a $^
@@ -93,13 +99,13 @@ libxlutil.so.$(XLUMAJOR): libxlutil.so.$(XLUMAJOR).$(XLUMINOR)
        ln -sf $< $@
 
 libxlutil.so.$(XLUMAJOR).$(XLUMINOR): $(LIBXLU_OBJS)
-       $(CC) $(CFLAGS) $(LDFLAGS) -Wl,$(SONAME_LDFLAG) -Wl,libxlutil.so.$(XLUMAJOR) $(SHLIB_LDFLAGS) -o $@ $^
+       $(CC) $(CFLAGS) $(LDFLAGS) -Wl,$(SONAME_LDFLAG) -Wl,libxlutil.so.$(XLUMAJOR) $(SHLIB_LDFLAGS) -o $@ $^ $(LIBXLU_LIBS)
 
 libxlutil.a: $(LIBXLU_OBJS)
        $(AR) rcs libxlutil.a $^
 
 $(CLIENTS): $(XL_OBJS) libxlutil.so libxenlight.so
-       $(CC) $(LDFLAGS) -o $@ $^ $(LIBS)
+       $(CC) $(LDFLAGS) -o $@ $(XL_OBJS) libxlutil.so libxenlight.so $(CLIENT_LIBS)
 
 .PHONY: install
 install: all

diff --git a/tools/python/setup.py b/tools/python/setup.py
index 28c4d85e6724ebac5455030a9a84b0ca7e4382ba..f803632d3b13a3cee5043d010719681e2def2a14 100644 (file)
--- a/tools/python/setup.py
+++ b/tools/python/setup.py
@@ -6,119 +6,98 @@ XEN_ROOT = "../.."
 
 extra_compile_args  = [ "-fno-strict-aliasing", "-Werror" ]
 
-include_dirs = [ XEN_ROOT + "/tools/libxc",
-                 XEN_ROOT + "/tools/xenstore",
-                 XEN_ROOT + "/tools/include",
-                 XEN_ROOT + "/tools/libxl",
-                 ]
-
-library_dirs = [ XEN_ROOT + "/tools/libxc",
-                 XEN_ROOT + "/tools/xenstore",
-                 XEN_ROOT + "/tools/libxl"
-                 ]
-
-libraries = [ "xenctrl", "xenguest", "xenstore" ]
-
-depends = [ XEN_ROOT + "/tools/libxc/libxenctrl.so",
-            XEN_ROOT + "/tools/libxc/libxenguest.so",
-            XEN_ROOT + "/tools/xenstore/libxenstore.so"
-            ]
-
-plat = os.uname()[0]
-if plat == 'Linux':
-    uuid_libs = ["uuid"]
-    blktap_ctl_libs = ["blktapctl"]
-    library_dirs.append(XEN_ROOT + "/tools/blktap2/control")
-    blktab_ctl_depends = [ XEN_ROOT + "/tools/blktap2/control/libblktapctl.so" ]
-else:
-    uuid_libs = []
-    blktap_ctl_libs = []
-    blktab_ctl_depends = []
+PATH_XEN      = XEN_ROOT + "/tools/include"
+PATH_LIBXC    = XEN_ROOT + "/tools/libxc"
+PATH_LIBXL    = XEN_ROOT + "/tools/libxl"
+PATH_XENSTORE = XEN_ROOT + "/tools/xenstore"
 
 xc = Extension("xc",
                extra_compile_args = extra_compile_args,
-               include_dirs       = include_dirs + [ "xen/lowlevel/xc" ],
-               library_dirs       = library_dirs,
-               libraries          = libraries,
-               depends            = depends,
+               include_dirs       = [ PATH_XEN, PATH_LIBXC, "xen/lowlevel/xc" ],
+               library_dirs       = [ PATH_LIBXC ],
+               libraries          = [ "xenctrl", "xenguest" ],
+               depends            = [ PATH_LIBXC + "/libxenctrl.so", PATH_LIBXC + "/libxenguest.so" ],
                sources            = [ "xen/lowlevel/xc/xc.c" ])
 
 xs = Extension("xs",
                extra_compile_args = extra_compile_args,
-               include_dirs       = include_dirs + [ "xen/lowlevel/xs" ],
-               library_dirs       = library_dirs,
-               libraries          = libraries,
-               depends            = depends,
+               include_dirs       = [ PATH_XEN, PATH_XENSTORE, "xen/lowlevel/xs" ],
+               library_dirs       = [ PATH_XENSTORE ],
+               libraries          = [ "xenstore" ],
+               depends            = [ PATH_XENSTORE + "/libxenstore.so" ],
                sources            = [ "xen/lowlevel/xs/xs.c" ])
 
 scf = Extension("scf",
                extra_compile_args = extra_compile_args,
-               include_dirs       = include_dirs + [ "xen/lowlevel/scf" ],
-               library_dirs       = library_dirs,
-               libraries          = libraries,
-               depends            = depends,
+               include_dirs       = [ "xen/lowlevel/scf" ],
+               library_dirs       = [ ],
+               libraries          = [ ],
+               depends            = [ ],
                sources            = [ "xen/lowlevel/scf/scf.c" ])
-             
+
 process = Extension("process",
                extra_compile_args = extra_compile_args,
-               include_dirs       = include_dirs + [ "xen/lowlevel/process" ],
-               library_dirs       = library_dirs,
-               libraries          = libraries + [ "contract" ],
-               depends            = depends,
+               include_dirs       = [ "xen/lowlevel/process" ],
+               library_dirs       = [ ],
+               libraries          = [ "contract" ],
+               depends            = [ ],
                sources            = [ "xen/lowlevel/process/process.c" ])
 
 acm = Extension("acm",
                extra_compile_args = extra_compile_args,
-               include_dirs       = include_dirs + [ "xen/lowlevel/acm" ],
-               library_dirs       = library_dirs,
-               libraries          = libraries,
-               depends            = depends,
+               include_dirs       = [ PATH_XEN, PATH_LIBXC, "xen/lowlevel/acm" ],
+               library_dirs       = [ PATH_LIBXC ],
+               libraries          = [ "xenctrl" ],
+               depends            = [ PATH_LIBXC + "/libxenctrl.so" ],
                sources            = [ "xen/lowlevel/acm/acm.c" ])
 
 flask = Extension("flask",
                extra_compile_args = extra_compile_args,
-               include_dirs       = include_dirs + [ "xen/lowlevel/flask" ] + 
-                                        [ "../flask/libflask/include" ],
-               library_dirs       = library_dirs + [ "../flask/libflask" ],
-               libraries          = libraries + [ "flask" ],
-               depends            = depends + [ XEN_ROOT + "/tools/flask/libflask/libflask.so" ],
+               include_dirs       = [ PATH_XEN, PATH_LIBXC, "xen/lowlevel/flask",
+                                      "../flask/libflask/include" ],
+               library_dirs       = [ PATH_LIBXC, "../flask/libflask" ],
+               libraries          = [ "xenctrl", "flask" ],
+               depends            = [ PATH_LIBXC + "/libxenctrl.so",
+                                      XEN_ROOT + "/tools/flask/libflask/libflask.so" ],
                sources            = [ "xen/lowlevel/flask/flask.c" ])
 
 ptsname = Extension("ptsname",
                extra_compile_args = extra_compile_args,
-               include_dirs       = include_dirs + [ "ptsname" ],
-               library_dirs       = library_dirs,
-               libraries          = libraries,
-               depends            = depends,
+               include_dirs       = [ "ptsname" ],
+               library_dirs       = [ ],
+               libraries          = [ ],
+               depends            = [ ],
                sources            = [ "ptsname/ptsname.c" ])
 
 checkpoint = Extension("checkpoint",
-                       extra_compile_args = extra_compile_args,
-                       include_dirs       = include_dirs,
-                       library_dirs       = library_dirs,
-                       libraries          = libraries + [ "rt" ],
-                       depends            = depends,
-                       sources            = [ "xen/lowlevel/checkpoint/checkpoint.c",
-                                              "xen/lowlevel/checkpoint/libcheckpoint.c"])
+               extra_compile_args = extra_compile_args,
+               include_dirs       = [ PATH_XEN, PATH_LIBXC, PATH_XENSTORE ],
+               library_dirs       = [ PATH_LIBXC, PATH_XENSTORE ],
+               libraries          = [ "xenctrl", "xenguest", "xenstore", "rt" ],
+               depends            = [ PATH_LIBXC + "/libxenctrl.so",
+                                      PATH_LIBXC + "/libxenguest.so",
+                                      PATH_XENSTORE + "/libxenstore.so" ],
+               sources            = [ "xen/lowlevel/checkpoint/checkpoint.c",
+                                      "xen/lowlevel/checkpoint/libcheckpoint.c"])
 
 netlink = Extension("netlink",
-                    extra_compile_args = extra_compile_args,
-                    include_dirs       = include_dirs,
-                    library_dirs       = library_dirs,
-                    libraries          = libraries,
-                    depends            = depends,
-                    sources            = [ "xen/lowlevel/netlink/netlink.c",
-                                           "xen/lowlevel/netlink/libnetlink.c"])
+               extra_compile_args = extra_compile_args,
+               include_dirs       = [ ],
+               library_dirs       = [ ],
+               libraries          = [ ],
+               depends            = [ ],
+               sources            = [ "xen/lowlevel/netlink/netlink.c",
+                                      "xen/lowlevel/netlink/libnetlink.c"])
 
 xl = Extension("xl",
                extra_compile_args = extra_compile_args,
-               include_dirs       = include_dirs + [ "xen/lowlevel/xl" ],
-               library_dirs       = library_dirs,
-               libraries          = libraries + ["xenlight" ] + blktap_ctl_libs + uuid_libs,
-               depends            = depends + blktab_ctl_depends +
-                                    [ XEN_ROOT + "/tools/libxl/libxenlight.so" ],
+               include_dirs       = [ PATH_XEN, PATH_LIBXL, PATH_LIBXC, PATH_XENSTORE, "xen/lowlevel/xl" ],
+               library_dirs       = [ PATH_LIBXL ],
+               libraries          = [ "xenlight" ],
+               depends            = [ PATH_LIBXL + "/libxenlight.so" ],
                sources            = [ "xen/lowlevel/xl/xl.c", "xen/lowlevel/xl/_pyxl_types.c" ])
 
+plat = os.uname()[0]
 modules = [ xc, xs, ptsname, acm, flask, xl ]
 if plat == 'SunOS':
     modules.extend([ scf, process ])
@@ -143,7 +122,6 @@ setup(name            = 'xen',
                          'xen.sv',
                          'xen.xsview',
                          'xen.remus',
-
                          'xen.xend.tests',
                          'xen.xend.server.tests',
                          'xen.xend.xenstore.tests',

diff --git a/tools/python/xen/lowlevel/xl/xl.c b/tools/python/xen/lowlevel/xl/xl.c
index 14ad809f0f7603ea5b16e78e2671ff8b13a94e1f..07c29d4a25d9b1fe3a14d8da190bf860cdd831de 100644 (file)
--- a/tools/python/xen/lowlevel/xl/xl.c
+++ b/tools/python/xen/lowlevel/xl/xl.c
@@ -35,7 +35,6 @@
 #include <sys/socket.h>
 #include <sys/select.h>
 #include <arpa/inet.h>
-#include <xenctrl.h>
 #include <ctype.h>
 #include <inttypes.h>
 

diff --git a/tools/python/xen/lowlevel/xs/xs.c b/tools/python/xen/lowlevel/xs/xs.c
index 7f28aa291a8fdbb82bca9374ebecbd451170ce6d..76a00a42a24ca97786bc070da0650c1c2053bb7f 100644 (file)
--- a/tools/python/xen/lowlevel/xs/xs.c
+++ b/tools/python/xen/lowlevel/xs/xs.c
@@ -30,7 +30,6 @@
 #include <fcntl.h>
 #include <errno.h>
 
-#include <xenctrl.h>
 #include "xs.h"
 
 /** @file