Emits reload to systemd when needed

The current implementation enforce the reload
when a 'wants' target is created or deleted.
This should work well for system units.
However, for system units, this behaviour isn't
enought when more that a user is active because
only the user that installs the application will
be updated. For this reason, a paralelle mechanism
has to be defined.

Also note that systemd is henceforth required for
tools because wgtpkg-installer needs it now.

Change-Id: I4fc03a44dbc58c2374ea21dbf6b436f646d04e00
Signed-off-by: José Bollo <jose.bollo@iot.bzh>

4 files changed, 133 insertions, 66 deletions

diff --git a/src/CMakeLists.txt b/src/CMakeLists.txt
index f121a62..41c2b1e 100644
--- a/src/CMakeLists.txt
+++ b/src/CMakeLists.txt
@@ -41,7 +41,7 @@ set(CMAKE_C_FLAGS_CCOV         "-g -O2 --coverage")
 
 include(FindPkgConfig)
 
-pkg_check_modules(EXTRAS REQUIRED libxml-2.0 openssl xmlsec1 xmlsec1-openssl json-c)
+pkg_check_modules(EXTRAS REQUIRED libxml-2.0 openssl xmlsec1 xmlsec1-openssl json-c libsystemd>=222)
 add_compile_options(${EXTRAS_CFLAGS})
 include_directories(${EXTRAS_INCLUDE_DIRS})
 link_libraries(${EXTRAS_LIBRARIES})
@@ -100,6 +100,7 @@ add_library(utils STATIC
 	utils-dir.c
 	utils-file.c
 	utils-json.c
+	utils-jbus.c
 	utils-systemd.c
 	verbose.c
 	)
@@ -116,6 +117,13 @@ add_library(secwrp STATIC
 	secmgr-wrap.c
 	)
 
+add_library(afm STATIC
+	afm-db.c
+	afm-launch.c
+	afm-launch-mode.c
+	afm-run.c
+	)
+
 ###########################################################################
 # packaging tools
 
@@ -136,60 +144,38 @@ target_link_libraries(wgtpkg-installer wgtpkg wgt secwrp utils)
 install(TARGETS wgtpkg-sign wgtpkg-pack wgtpkg-info wgtpkg-installer DESTINATION ${CMAKE_INSTALL_BINDIR})
 
 ###########################################################################
-# the targeted
-
-pkg_check_modules(SYSTEMD libsystemd>=222)
-if(SYSTEMD_FOUND)
-	add_compile_options(${SYSTEMD_CFLAGS})
-	include_directories(${SYSTEMD_INCLUDE_DIRS})
-	link_libraries(${SYSTEMD_LIBRARIES})
-
-	add_library(utils2 STATIC
-		utils-jbus.c
-		)
-
-	add_library(afm STATIC
-		afm-db.c
-		afm-launch.c
-		afm-launch-mode.c
-		afm-run.c
-		)
-
-	###########################################################################
-	# the daemons
-	MESSAGE(STATUS "Creating daemons")
-
-	add_executable(afm-user-daemon afm-user-daemon.c)
-	target_link_libraries(afm-user-daemon afm secwrp wgt utils utils2)
-	install(TARGETS afm-user-daemon DESTINATION ${CMAKE_INSTALL_BINDIR})
-
-	add_executable(afm-system-daemon afm-system-daemon.c)
-	target_link_libraries(afm-system-daemon wgtpkg afm secwrp wgt utils utils2)
-	install(TARGETS afm-system-daemon DESTINATION ${CMAKE_INSTALL_BINDIR})
-
-	###########################################################################
-	# the binding for afb
-
-	pkg_check_modules(AFB afb-daemon)
-	if(AFB_FOUND)
-		message(STATUS "Creation afm-main-binding for AFB-DAEMON")
-		###############################################################
-		pkg_get_variable(afb_binding_install_dir afb-daemon binding_install_dir)
-		###############################################################
-		add_library(afm-main-binding MODULE afm-main-binding.c)
-		target_compile_options(afm-main-binding PRIVATE ${AFB_CFLAGS})
-		target_include_directories(afm-main-binding PRIVATE ${AFB_INCLUDE_DIRS})
-		target_link_libraries(afm-main-binding utils utils2 ${AFB_LIBRARIES})
-		set_target_properties(afm-main-binding PROPERTIES
-			PREFIX ""
-			LINK_FLAGS "-Wl,--version-script=${CMAKE_CURRENT_SOURCE_DIR}/afm-main-binding.export-map"
-		)
-		install(TARGETS afm-main-binding LIBRARY DESTINATION ${afb_binding_install_dir})
-	else()
-		message(STATUS "Not creating the binding for AFB-DAEMON")
-	endif()
-
-endif(SYSTEMD_FOUND)
+# the daemons
+MESSAGE(STATUS "Creating daemons")
+
+add_executable(afm-user-daemon afm-user-daemon.c)
+target_link_libraries(afm-user-daemon afm secwrp wgt utils)
+install(TARGETS afm-user-daemon DESTINATION ${CMAKE_INSTALL_BINDIR})
+
+add_executable(afm-system-daemon afm-system-daemon.c)
+target_link_libraries(afm-system-daemon wgtpkg afm secwrp wgt utils)
+install(TARGETS afm-system-daemon DESTINATION ${CMAKE_INSTALL_BINDIR})
+
+###########################################################################
+# the binding for afb
+
+pkg_check_modules(AFB afb-daemon)
+if(AFB_FOUND)
+	message(STATUS "Creation afm-main-binding for AFB-DAEMON")
+	###############################################################
+	pkg_get_variable(afb_binding_install_dir afb-daemon binding_install_dir)
+	###############################################################
+	add_library(afm-main-binding MODULE afm-main-binding.c)
+	target_compile_options(afm-main-binding PRIVATE ${AFB_CFLAGS})
+	target_include_directories(afm-main-binding PRIVATE ${AFB_INCLUDE_DIRS})
+	target_link_libraries(afm-main-binding utils ${AFB_LIBRARIES})
+	set_target_properties(afm-main-binding PROPERTIES
+		PREFIX ""
+		LINK_FLAGS "-Wl,--version-script=${CMAKE_CURRENT_SOURCE_DIR}/afm-main-binding.export-map"
+	)
+	install(TARGETS afm-main-binding LIBRARY DESTINATION ${afb_binding_install_dir})
+else()
+	message(STATUS "Not creating the binding for AFB-DAEMON")
+endif()
 
 ###########################################################################
 # the tests
diff --git a/src/utils-systemd.c b/src/utils-systemd.c
index 757a52c..48fb3d8 100644
--- a/src/utils-systemd.c
+++ b/src/utils-systemd.c
@@ -33,6 +33,35 @@
 # define SYSTEMD_UNITS_ROOT "/usr/local/lib/systemd"
 #endif
 
+static const char sdb_path[] = "/org/freedesktop/systemd1";
+static const char sdb_destination[] = "org.freedesktop.systemd1";
+static const char sdbi_manager[] = "org.freedesktop.systemd1.Manager";
+static const char sdbm_reload[] = "Reload";
+
+static struct sd_bus *sysbus;
+static struct sd_bus *usrbus;
+
+static int get_bus(int isuser, struct sd_bus **ret)
+{
+	int rc;
+	struct sd_bus *bus;
+
+	bus = isuser ? usrbus : sysbus;
+	if (bus) {
+		*ret = bus;
+		rc = 0;
+	} else if (isuser) {
+		rc = sd_bus_open_user(ret);
+		if (!rc)
+			usrbus = *ret;
+	} else {
+		rc = sd_bus_open_system(ret);
+		if (!rc)
+			sysbus = *ret;
+	}
+	return rc;
+}
+
 int systemd_get_unit_path(char *path, size_t pathlen, int isuser, const char *unit, const char *uext)
 {
 	int rc = snprintf(path, pathlen, "%s/%s/%s.%s", 
@@ -75,3 +104,15 @@ int systemd_get_wants_target(char *path, size_t pathlen, const char *unit, const
 	return rc;
 }
 
+int systemd_daemon_reload(int isuser)
+{
+	int rc;
+	struct sd_bus *bus;
+
+	rc = get_bus(isuser, &bus);
+	if (!rc) {
+		rc = sd_bus_call_method(bus, sdb_destination, sdb_path, sdbi_manager, sdbm_reload, NULL, NULL, NULL);
+	}
+	return rc;
+}
+
diff --git a/src/utils-systemd.h b/src/utils-systemd.h
index d149309..30f9522 100644
--- a/src/utils-systemd.h
+++ b/src/utils-systemd.h
@@ -21,4 +21,5 @@
 extern int systemd_get_unit_path(char *path, size_t pathlen, int isuser, const char *unit, const char *uext);
 extern int systemd_get_wants_path(char *path, size_t pathlen, int isuser, const char *wanter, const char *unit, const char *uext);
 extern int systemd_get_wants_target(char *path, size_t pathlen, const char *unit, const char *uext);
+extern int systemd_daemon_reload(int isuser);
 
diff --git a/src/wgtpkg-unit.c b/src/wgtpkg-unit.c
index f141766..48cf3bb 100644
--- a/src/wgtpkg-unit.c
+++ b/src/wgtpkg-unit.c
@@ -419,28 +419,63 @@ static int get_wants_target(char *path, size_t pathlen, const struct unitdesc *d
 	return rc;
 }
 
+static int do_send_reload(const struct unitdesc descs[], unsigned count)
+{
+	unsigned i;
+	int reloadsys, reloadusr;
+
+	reloadsys = reloadusr = 0;
+	for (i = 0 ; i < count ; i++) {
+		if (descs[i].wanted_by != NULL) {
+			switch (descs[i].scope) {
+			case unitscope_user:
+				reloadusr = 1;
+				break;
+			case unitscope_system:
+				reloadsys = 1;
+				break;
+			default:
+				break;
+			}
+		}
+	}
+
+	if (reloadusr)
+		reloadusr = systemd_daemon_reload(1);
+	if (reloadsys)
+		reloadsys = systemd_daemon_reload(0);
+	return reloadsys ? : reloadusr ? : 0;
+}
+
 static int do_uninstall_units(void *closure, const struct unitdesc descs[], unsigned count)
 {
 	int rc, rc2;
 	unsigned i;
 	char path[PATH_MAX];
 
+	rc = 0;
 	for (i = 0 ; i < count ; i++) {
-		rc = check_unit_desc(&descs[i], 0);
-		if (rc == 0) {
-			rc = get_unit_path(path, sizeof path, &descs[i]);
-			if (rc >= 0) {
-				rc = unlink(path);
+		rc2 = check_unit_desc(&descs[i], 0);
+		if (rc2 == 0) {
+			rc2 = get_unit_path(path, sizeof path, &descs[i]);
+			if (rc2 >= 0) {
+				rc2 = unlink(path);
 			}
+			if (rc2 < 0 && rc == 0)
+				rc = rc2;
 			if (descs[i].wanted_by != NULL) {
 				rc2 = get_wants_path(path, sizeof path, &descs[i]);
 				if (rc2 >= 0)
 					rc2 = unlink(path);
-				rc = rc < 0 ? rc : rc2;
 			}
 		}
+		if (rc2 < 0 && rc == 0)
+			rc = rc2;
 	}
-	return 0;
+	rc2 = do_send_reload(descs, count);
+	if (rc2 < 0 && rc == 0)
+		rc = rc2;
+	return rc;
 }
 
 static int do_install_units(void *closure, const struct unitdesc descs[], unsigned count)
@@ -469,12 +504,16 @@ static int do_install_units(void *closure, const struct unitdesc descs[], unsign
 				i++;
 			}
 		}
-		if (rc < 0) {
-			do_uninstall_units(closure, descs, i);
-			return rc;
-		}
+		if (rc < 0)
+			goto error;
 	}
+	rc = do_send_reload(descs, count);
+	if (rc < 0)
+		goto error;
 	return 0;
+error:
+	do_uninstall_units(closure, descs, i);
+	return rc;
 }
 
 static int add_metadata(struct json_object *jdesc, const char *installdir, const char *icondir, int port)