build-sys: merge libsystemd-login into libsystemd

A compatibility libsystemd-login library is created which uses
.symver and ifunc magic proposed by Lennart to make programs linked
to the old library name continue to work seamlessly.

Unfortunately the bfd linker crashes:
  https://sourceware.org/bugzilla/show_bug.cgi?id=16467
This will be fixed in binutils 2.25.

As a work-around, gold can be used:
  LDFLAGS=-Wl,-fuse-ld=gold

Unfortunately the switch to pick the linker appeared in gcc 4.8.

This also doesn't work with LLVM:
  http://llvm.org/bugs/show_bug.cgi?id=11897

4 files changed, 120 insertions, 74 deletions

diff --git a/.gitignore b/.gitignore
index b706ab9522..36b91b4a7d 100644
--- a/.gitignore
+++ b/.gitignore
@@ -33,6 +33,7 @@
 /hostnamectl
 /install-tree
 /journalctl
+/libsystemd-login.c
 /libtool
 /localectl
 /loginctl
diff --git a/Makefile.am b/Makefile.am
index 6c4f834344..53707d999e 100644
--- a/Makefile.am
+++ b/Makefile.am
@@ -44,7 +44,7 @@ LIBGUDEV_REVISION=3
 LIBGUDEV_AGE=1
 
 LIBSYSTEMD_LOGIN_CURRENT=9
-LIBSYSTEMD_LOGIN_REVISION=1
+LIBSYSTEMD_LOGIN_REVISION=2
 LIBSYSTEMD_LOGIN_AGE=9
 
 LIBSYSTEMD_DAEMON_CURRENT=0
@@ -1804,14 +1804,7 @@ systemctl_LDADD = \
 	libsystemd-units.la \
 	libsystemd-label.la \
 	libsystemd-internal.la \
-	libsystemd-logs.la
-
-if ENABLE_LOGIND
-systemctl_LDADD += \
-	libsystemd-login-internal.la
-endif
-
-systemctl_LDADD += \
+	libsystemd-logs.la \
 	libsystemd-journal-internal.la \
 	libsystemd-id128-internal.la \
 	libsystemd-daemon-internal.la \
@@ -1986,6 +1979,7 @@ libsystemd_la_SOURCES = \
 	src/systemd/sd-event.h \
 	src/systemd/sd-rtnl.h \
 	src/systemd/sd-resolve.h \
+	src/systemd/sd-login.h \
 	src/libsystemd/sd-bus/sd-bus.c \
 	src/libsystemd/sd-bus/bus-control.c \
 	src/libsystemd/sd-bus/bus-control.h \
@@ -2032,7 +2026,10 @@ libsystemd_la_SOURCES = \
 	src/libsystemd/sd-rtnl/rtnl-util.h \
 	src/libsystemd/sd-rtnl/rtnl-util.c \
 	src/libsystemd/sd-resolve/sd-resolve.c \
-	src/libsystemd/sd-resolve/resolve-util.h
+	src/libsystemd/sd-resolve/resolve-util.h \
+	src/login/sd-login.c \
+	src/login/login-shared.c \
+	src/login/login-shared.h
 
 nodist_libsystemd_la_SOURCES = \
 	src/libsystemd/sd-bus/bus-error-mapping.c
@@ -3272,11 +3269,6 @@ libsystemd_journal_core_la_LIBADD = \
 	libsystemd-id128-internal.la \
 	libsystemd-shared.la
 
-if ENABLE_LOGIND
-libsystemd_journal_core_la_LIBADD += \
-	libsystemd-login-internal.la
-endif
-
 if HAVE_ACL
 libsystemd_journal_core_la_LIBADD += \
 	libsystemd-acl.la
@@ -3474,12 +3466,8 @@ systemd_coredump_SOURCES = \
 systemd_coredump_LDADD = \
 	libsystemd-journal-internal.la \
 	libsystemd-label.la \
-	libsystemd-shared.la
-
-if ENABLE_LOGIND
-systemd_coredump_LDADD += \
-	libsystemd-login-internal.la
-endif
+	libsystemd-shared.la \
+	libsystemd-internal.la
 
 rootlibexec_PROGRAMS += \
 	systemd-coredump
@@ -4242,14 +4230,14 @@ test_login_SOURCES = \
 	src/login/test-login.c
 
 test_login_LDADD = \
-	libsystemd-login-internal.la \
+	libsystemd-internal.la \
 	libsystemd-shared.la
 
 test_login_shared_SOURCES = \
 	src/login/test-login-shared.c
 
 test_login_shared_LDADD = \
-	libsystemd-login-internal.la \
+	libsystemd-internal.la \
 	libsystemd-shared.la
 
 test_inhibit_SOURCES = \
@@ -4275,29 +4263,6 @@ tests += \
 	test-login-tables \
 	test-login-shared
 
-libsystemd_login_la_SOURCES = \
-	src/login/libsystemd-login.sym \
-	src/login/sd-login.c \
-	src/systemd/sd-login.h \
-	src/login/login-shared.c \
-	src/login/login-shared.h
-
-libsystemd_login_la_CFLAGS = \
-	$(AM_CFLAGS) \
-	-fvisibility=hidden
-
-libsystemd_login_la_LDFLAGS = \
-	$(AM_LDFLAGS) \
-	-version-info $(LIBSYSTEMD_LOGIN_CURRENT):$(LIBSYSTEMD_LOGIN_REVISION):$(LIBSYSTEMD_LOGIN_AGE) \
-	-Wl,--version-script=$(top_srcdir)/src/login/libsystemd-login.sym
-
-libsystemd_login_la_LIBADD = \
-	libsystemd-daemon-internal.la \
-	libsystemd-shared.la
-
-libsystemd_login_internal_la_SOURCES = \
-	$(libsystemd_login_la_SOURCES)
-
 if HAVE_PAM
 pam_systemd_la_SOURCES = \
 	src/login/pam-module.c
@@ -4330,16 +4295,6 @@ dist_pamconf_DATA = \
 	src/login/systemd-user
 endif
 
-# move lib from $(libdir) to $(rootlibdir) and update devel link, if needed
-libsystemd-login-install-hook:
-	libname=libsystemd-login.so && $(move-to-rootlibdir)
-
-libsystemd-login-uninstall-hook:
-	rm -f $(DESTDIR)$(rootlibdir)/libsystemd-login.so*
-
-INSTALL_EXEC_HOOKS += libsystemd-login-install-hook
-UNINSTALL_EXEC_HOOKS += libsystemd-login-uninstall-hook
-
 nodist_systemunit_DATA += \
 	units/systemd-logind.service \
 	units/systemd-user-sessions.service
@@ -4360,15 +4315,6 @@ dist_pkgsysconf_DATA += \
 pkginclude_HEADERS += \
 	src/systemd/sd-login.h
 
-lib_LTLIBRARIES += \
-	libsystemd-login.la
-
-noinst_LTLIBRARIES += \
-	libsystemd-login-internal.la
-
-pkgconfiglib_DATA += \
-	src/login/libsystemd-login.pc
-
 polkitpolicy_files += \
 	src/login/org.freedesktop.login1.policy
 
@@ -4536,7 +4482,7 @@ login_la_LDFLAGS = \
 login_la_LIBADD = \
 	$(PYTHON_DEVEL_LIBS) \
 	libsystemd-journal.la \
-	libsystemd-login.la \
+	libsystemd.la \
 	libsystemd-daemon-internal.la \
 	libsystemd-shared.la
 
@@ -4581,6 +4527,50 @@ clean-python:
 	-rm -f _daemon.la id128.la _journal.la login.la _reader.la
 
 # ------------------------------------------------------------------------------
+define generate-fake-lib
+	$(AM_V_at)$(MKDIR_P) $(dir $@)
+	$(AM_V_GEN)sed -r -n 's/^ +(sd_.*);/void new_\1(void);\n__asm__(".symver new_\1,\1@LIBSYSTEMD_209");\nstatic void (*resolve_\1(void)) (void) {\n\treturn new_\1;\n}\nvoid \1(void) __attribute__((ifunc("resolve_\1")));\n/p' <$< >$@
+endef
+
+libsystemd_login_la_SOURCES = \
+	libsystemd-login.c \
+	src/login/libsystemd-login.sym
+
+libsystemd_login_la_CFLAGS = \
+	$(AM_CFLAGS) \
+	-fvisibility=default
+
+libsystemd_login_la_LDFLAGS = \
+	$(AM_LDFLAGS) \
+	-version-info $(LIBSYSTEMD_LOGIN_CURRENT):$(LIBSYSTEMD_LOGIN_REVISION):$(LIBSYSTEMD_LOGIN_AGE) \
+	-Wl,--version-script=$(top_srcdir)/src/login/libsystemd-login.sym
+
+libsystemd_login_la_LIBADD = \
+	libsystemd.la
+
+BUILT_SOURCES += \
+	libsystemd-login.c
+
+libsystemd-login.c: src/login/libsystemd-login.sym
+	$(generate-fake-lib)
+
+lib_LTLIBRARIES += \
+	libsystemd-login.la
+
+pkgconfiglib_DATA += \
+	src/login/libsystemd-login.pc
+
+# move lib from $(libdir) to $(rootlibdir) and update devel link, if needed
+libsystemd-login-install-hook:
+	libname=libsystemd-login.so && $(move-to-rootlibdir)
+
+libsystemd-login-uninstall-hook:
+	rm -f $(DESTDIR)$(rootlibdir)/libsystemd-login.so*
+
+INSTALL_EXEC_HOOKS += libsystemd-login-install-hook
+UNINSTALL_EXEC_HOOKS += libsystemd-login-uninstall-hook
+
+# ------------------------------------------------------------------------------
 substitutions = \
        '|rootlibexecdir=$(rootlibexecdir)|' \
        '|rootbindir=$(rootbindir)|' \
@@ -4996,7 +4986,8 @@ endef
 test-libsystemd-sym.c: \
 	src/libsystemd/libsystemd.sym \
 	src/systemd/sd-bus.h \
-	src/systemd/sd-utf8.h
+	src/systemd/sd-utf8.h \
+	src/systemd/sd-login.h
 	$(generate-sym-test)
 
 test-libsystemd-daemon-sym.c: \
diff --git a/src/libsystemd/libsystemd.sym b/src/libsystemd/libsystemd.sym
index e2e917e00e..9b10604b53 100644
--- a/src/libsystemd/libsystemd.sym
+++ b/src/libsystemd/libsystemd.sym
@@ -9,6 +9,67 @@
 
 LIBSYSTEMD_209 {
 global:
+
+        /* originally LIBSYSTEMD_LOGIN_31 */
+        sd_get_seats;
+        sd_get_sessions;
+        sd_get_uids;
+        sd_login_monitor_flush;
+        sd_login_monitor_get_fd;
+        sd_login_monitor_new;
+        sd_login_monitor_unref;
+        sd_pid_get_owner_uid;
+        sd_pid_get_session;
+        sd_seat_can_multi_session;
+        sd_seat_get_active;
+        sd_seat_get_sessions;
+        sd_session_get_seat;
+        sd_session_get_uid;
+        sd_session_is_active;
+        sd_uid_get_seats;
+        sd_uid_get_sessions;
+        sd_uid_get_state;
+        sd_uid_is_on_seat;
+
+        /* originally LIBSYSTEMD_LOGIN_38 */
+        sd_pid_get_unit;
+        sd_session_get_service;
+
+        /* originally LIBSYSTEMD_LOGIN_43 */
+        sd_session_get_type;
+        sd_session_get_class;
+        sd_session_get_display;
+
+        /* originally LIBSYSTEMD_LOGIN_186 */
+        sd_session_get_state;
+        sd_seat_can_tty;
+        sd_seat_can_graphical;
+
+        /* originally LIBSYSTEMD_LOGIN_198 */
+        sd_session_get_tty;
+
+        /* originally LIBSYSTEMD_LOGIN_201 */
+        sd_login_monitor_get_events;
+        sd_login_monitor_get_timeout;
+
+        /* originally LIBSYSTEMD_LOGIN_202 */
+        sd_pid_get_user_unit;
+        sd_pid_get_machine_name;
+
+        /* originally LIBSYSTEMD_LOGIN_203 */
+        sd_get_machine_names;
+
+        /* originally LIBSYSTEMD_LOGIN_205 */
+        sd_pid_get_slice;
+
+        /* originally LIBSYSTEMD_LOGIN_207 */
+        sd_session_get_vt;
+
+        /* new in LIBSYSTEMD_LOGIN_209 */
+        sd_session_is_remote;
+        sd_session_get_remote_user;
+        sd_session_get_remote_host;
+
         /* Same order as in sd-bus.h should be used */
 
         /* Connections */
diff --git a/src/login/libsystemd-login.sym b/src/login/libsystemd-login.sym
index 1d3398253c..54aa91c609 100644
--- a/src/login/libsystemd-login.sym
+++ b/src/login/libsystemd-login.sym
@@ -85,10 +85,3 @@ LIBSYSTEMD_LOGIN_207 {
 global:
         sd_session_get_vt;
 } LIBSYSTEMD_LOGIN_205;
-
-LIBSYSTEMD_LOGIN_209 {
-global:
-        sd_session_is_remote;
-        sd_session_get_remote_user;
-        sd_session_get_remote_host;
-} LIBSYSTEMD_LOGIN_207;