From e94937df954451eb4aa63573f0d7404ed2db987e Mon Sep 17 00:00:00 2001

From: Lukas Nykryn <lnykryn@redhat.com>

Date: Wed, 8 Oct 2014 11:59:46 +0200

Subject: [PATCH] systemctl: add add-wants and add-requires verbs

---

 TODO                                   |   1 -

 man/systemctl.xml                      |  19 ++++++

 src/core/dbus-manager.c                |  83 +++++++++++++++++----------

 src/core/org.freedesktop.systemd1.conf |   4 ++

 src/core/selinux-access.c              |  29 ++++++++++

 src/core/selinux-access.h              |   3 +

 src/shared/install.c                   | 102 ++++++++++++++++++++++++++++++---

 src/shared/install.h                   |   2 +

 src/systemctl/systemctl.c              | 100 ++++++++++++++++++++++++++++++++

 9 files changed, 303 insertions(+), 40 deletions(-)

diff --git a/TODO b/TODO

index 10baa1cec3..b437166273 100644

--- a/TODO

+++ b/TODO

@@ -461,7 +461,6 @@ Features:

   - "systemctl mask" should find all names by which a unit is accessible

     (i.e. by scanning for symlinks to it) and link them all to /dev/null

   - systemctl list-unit-files should list generated files (and probably with a new state "generated" for them, or so)

-  - systemctl: maybe add "systemctl add-wants" or so...

 * timer units:

   - timer units should get the ability to trigger when:

diff --git a/man/systemctl.xml b/man/systemctl.xml

index b28a3b7e8a..b2aa17f22b 100644

--- a/man/systemctl.xml

+++ b/man/systemctl.xml

@@ -1098,6 +1098,25 @@ kobject-uevent 1 systemd-udevd-kernel.socket systemd-udevd.service

         </varlistentry>

         <varlistentry>

+          <term><command>add-wants <replaceable>TARGET</replaceable>

+          <replaceable>NAME</replaceable>...</command></term>

+          <term><command>add-requires <replaceable>TARGET</replaceable>

+          <replaceable>NAME</replaceable>...</command></term>

+

+          <listitem>

+            <para>Adds <literal>Wants=</literal> resp. <literal>Requires=</literal>

+            dependency to the specified <replaceable>TARGET</replaceable> for

+            one or more units. </para>

+

+            <para>This command honors <option>--system</option>,

+            <option>--user</option>, <option>--runtime</option> and

+            <option>--global</option> in a similar way as

+            <command>enable</command>.</para>

+

+          </listitem>

+        </varlistentry>

+

+        <varlistentry>

           <term><command>link <replaceable>FILENAME</replaceable>...</command></term>

           <listitem>

diff --git a/src/core/dbus-manager.c b/src/core/dbus-manager.c

index 533ce439a7..57db1c9f6a 100644

--- a/src/core/dbus-manager.c

+++ b/src/core/dbus-manager.c

@@ -1562,9 +1562,6 @@ static int method_enable_unit_files_generic(

                 sd_bus_error *error) {

         _cleanup_strv_free_ char **l = NULL;

-#ifdef HAVE_SELINUX

-        char **i;

-#endif

         UnitFileChange *changes = NULL;

         unsigned n_changes = 0;

         UnitFileScope scope;

@@ -1588,18 +1585,9 @@ static int method_enable_unit_files_generic(

         if (r < 0)

                 return r;

-#ifdef HAVE_SELINUX

-        STRV_FOREACH(i, l) {

-                Unit *u;

-

-                u = manager_get_unit(m, *i);

-                if (u) {

-                        r = selinux_unit_access_check(u, message, verb, error);

-                        if (r < 0)

-                                return r;

-                }

-        }

-#endif

+        r = selinux_unit_access_check_strv(l, message, m, verb, error);

+        if (r < 0)

+                return r;

         scope = m->running_as == SYSTEMD_SYSTEM ? UNIT_FILE_SYSTEM : UNIT_FILE_USER;

@@ -1637,9 +1625,6 @@ static int method_mask_unit_files(sd_bus *bus, sd_bus_message *message, void *us

 static int method_preset_unit_files_with_mode(sd_bus *bus, sd_bus_message *message, void *userdata, sd_bus_error *error) {

         _cleanup_strv_free_ char **l = NULL;

-#ifdef HAVE_SELINUX

-        char **i;

-#endif

         UnitFileChange *changes = NULL;

         unsigned n_changes = 0;

         Manager *m = userdata;

@@ -1674,18 +1659,9 @@ static int method_preset_unit_files_with_mode(sd_bus *bus, sd_bus_message *messa

                         return -EINVAL;

         }

-#ifdef HAVE_SELINUX

-        STRV_FOREACH(i, l) {

-                Unit *u;

-

-                u = manager_get_unit(m, *i);

-                if (u) {

-                        r = selinux_unit_access_check(u, message, "enable", error);

-                        if (r < 0)

-                                return r;

-                }

-        }

-#endif

+        r = selinux_unit_access_check_strv(l, message, m, "enable", error);

+        if (r < 0)

+                return r;

         scope = m->running_as == SYSTEMD_SYSTEM ? UNIT_FILE_SYSTEM : UNIT_FILE_USER;

@@ -1828,6 +1804,52 @@ static int method_preset_all_unit_files(sd_bus *bus, sd_bus_message *message, vo

         return reply_unit_file_changes_and_free(m, bus, message, -1, changes, n_changes);

 }

+static int method_add_dependency_unit_files(sd_bus *bus, sd_bus_message *message, void *userdata, sd_bus_error *error) {

+        _cleanup_strv_free_ char **l = NULL;

+        Manager *m = userdata;

+        UnitFileChange *changes = NULL;

+        unsigned n_changes = 0;

+        UnitFileScope scope;

+        int runtime, force, r;

+        char *target;

+        char *type;

+        UnitDependency dep;

+

+        assert(bus);

+        assert(message);

+        assert(m);

+

+        r = bus_verify_manage_unit_files_async(m, message, error);

+        if (r < 0)

+                return r;

+        if (r == 0)

+                return 1; /* No authorization for now, but the async polkit stuff will call us again when it has it */

+

+        r = sd_bus_message_read_strv(message, &l);

+        if (r < 0)

+                return r;

+

+        r = sd_bus_message_read(message, "ssbb", &target, &type, &runtime, &force);

+        if (r < 0)

+                return r;

+

+        dep = unit_dependency_from_string(type);

+        if (dep < 0)

+                return -EINVAL;

+

+        r = selinux_unit_access_check_strv(l, message, m, "enable", error);

+        if (r < 0)

+                return r;

+

+        scope = m->running_as == SYSTEMD_SYSTEM ? UNIT_FILE_SYSTEM : UNIT_FILE_USER;

+

+        r = unit_file_add_dependency(scope, runtime, NULL, l, target, dep, force, &changes, &n_changes);

+        if (r < 0)

+                return r;

+

+        return reply_unit_file_changes_and_free(m, bus, message, -1, changes, n_changes);

+}

+

 const sd_bus_vtable bus_manager_vtable[] = {

         SD_BUS_VTABLE_START(0),

@@ -1918,6 +1940,7 @@ const sd_bus_vtable bus_manager_vtable[] = {

         SD_BUS_METHOD("SetDefaultTarget", "sb", "a(sss)", method_set_default_target, SD_BUS_VTABLE_UNPRIVILEGED),

         SD_BUS_METHOD("GetDefaultTarget", NULL, "s", method_get_default_target, SD_BUS_VTABLE_UNPRIVILEGED),

         SD_BUS_METHOD("PresetAllUnitFiles", "sbb", "a(sss)", method_preset_all_unit_files, SD_BUS_VTABLE_UNPRIVILEGED),

+        SD_BUS_METHOD("AddDependencyUnitFiles", "asssbb", "a(sss)", method_add_dependency_unit_files, SD_BUS_VTABLE_UNPRIVILEGED),

         SD_BUS_SIGNAL("UnitNew", "so", 0),

         SD_BUS_SIGNAL("UnitRemoved", "so", 0),

diff --git a/src/core/org.freedesktop.systemd1.conf b/src/core/org.freedesktop.systemd1.conf

index 3e1382524a..6a7a37ee92 100644

--- a/src/core/org.freedesktop.systemd1.conf

+++ b/src/core/org.freedesktop.systemd1.conf

@@ -199,6 +199,10 @@

                        send_member="PresetAllUnitFiles"/>

+                       send_interface="org.freedesktop.systemd1.Manager"

+                       send_member="AddDependencyUnitFiles"/>

+

+                

                        send_interface="org.freedesktop.systemd1.Job"

                        send_member="Cancel"/>

diff --git a/src/core/selinux-access.c b/src/core/selinux-access.c

index cdbfb83a1a..184f202c1e 100644

--- a/src/core/selinux-access.c

+++ b/src/core/selinux-access.c

@@ -250,6 +250,27 @@ finish:

         return r;

 }

+int selinux_unit_access_check_strv(char **units,

+                                sd_bus_message *message,

+                                Manager *m,

+                                const char *permission,

+                                sd_bus_error *error) {

+        char **i;

+        Unit *u;

+        int r;

+

+        STRV_FOREACH(i, units) {

+                u = manager_get_unit(m, *i);

+                if (u) {

+                        r = selinux_unit_access_check(u, message, permission, error);

+                        if (r < 0)

+                                return r;

+                }

+        }

+

+        return 0;

+}

+

 #else

 int selinux_generic_access_check(

@@ -264,4 +285,12 @@ int selinux_generic_access_check(

 void selinux_access_free(void) {

 }

+int selinux_unit_access_check_strv(char **units,

+                                sd_bus_message *message,

+                                Manager *m,

+                                const char *permission,

+                                sd_bus_error *error) {

+        return 0;

+}

+

 #endif

diff --git a/src/core/selinux-access.h b/src/core/selinux-access.h

index 27d9e14591..6a4362a73c 100644

--- a/src/core/selinux-access.h

+++ b/src/core/selinux-access.h

@@ -24,11 +24,14 @@

 #include "sd-bus.h"

 #include "bus-error.h"

 #include "bus-util.h"

+#include "manager.h"

 void selinux_access_free(void);

 int selinux_generic_access_check(sd_bus_message *message, const char *path, const char *permission, sd_bus_error *error);

+int selinux_unit_access_check_strv(char **units, sd_bus_message *message, Manager *m, const char *permission, sd_bus_error *error);

+

 #ifdef HAVE_SELINUX

 #define selinux_access_check(message, permission, error) \

diff --git a/src/shared/install.c b/src/shared/install.c

index 945bb2748d..ff5dcbac15 100644

--- a/src/shared/install.c

+++ b/src/shared/install.c

@@ -1042,7 +1042,8 @@ static int unit_file_load(

                 InstallInfo *info,

                 const char *path,

                 const char *root_dir,

-                bool allow_symlink) {

+                bool allow_symlink,

+                bool load) {

         const ConfigTableItem items[] = {

                 { "Install", "Alias",           config_parse_strv,             0, &info->aliases           },

@@ -1064,6 +1065,11 @@ static int unit_file_load(

         if (!isempty(root_dir))

                 path = strappenda(root_dir, "/", path);

+        if (!load) {

+                r = access(path, F_OK) ? -errno : 0;

+                return r;

+        }

+

         fd = open(path, O_RDONLY|O_CLOEXEC|O_NOCTTY|(allow_symlink ? 0 : O_NOFOLLOW));

         if (fd < 0)

                 return -errno;

@@ -1092,7 +1098,8 @@ static int unit_file_search(

                 InstallInfo *info,

                 LookupPaths *paths,

                 const char *root_dir,

-                bool allow_symlink) {

+                bool allow_symlink,

+                bool load) {

         char **p;

         int r;

@@ -1102,7 +1109,7 @@ static int unit_file_search(

         assert(paths);

         if (info->path)

-                return unit_file_load(c, info, info->path, root_dir, allow_symlink);

+                return unit_file_load(c, info, info->path, root_dir, allow_symlink, load);

         assert(info->name);

@@ -1113,7 +1120,7 @@ static int unit_file_search(

                 if (!path)

                         return -ENOMEM;

-                r = unit_file_load(c, info, path, root_dir, allow_symlink);

+                r = unit_file_load(c, info, path, root_dir, allow_symlink, load);

                 if (r >= 0) {

                         info->path = path;

                         path = NULL;

@@ -1142,7 +1149,7 @@ static int unit_file_search(

                         if (!path)

                                 return -ENOMEM;

-                        r = unit_file_load(c, info, path, root_dir, allow_symlink);

+                        r = unit_file_load(c, info, path, root_dir, allow_symlink, load);

                         if (r >= 0) {

                                 info->path = path;

                                 path = NULL;

@@ -1175,7 +1182,7 @@ static int unit_file_can_install(

         assert_se(i = hashmap_first(c.will_install));

-        r = unit_file_search(&c, i, paths, root_dir, allow_symlink);

+        r = unit_file_search(&c, i, paths, root_dir, allow_symlink, true);

         if (r >= 0)

                 r =

@@ -1402,7 +1409,7 @@ static int install_context_apply(

                 assert_se(hashmap_move_one(c->have_installed, c->will_install, i->name) == 0);

-                q = unit_file_search(c, i, paths, root_dir, false);

+                q = unit_file_search(c, i, paths, root_dir, false, true);

                 if (q < 0) {

                         if (r >= 0)

                                 r = q;

@@ -1443,7 +1450,7 @@ static int install_context_mark_for_removal(

                 assert_se(hashmap_move_one(c->have_installed, c->will_install, i->name) == 0);

-                q = unit_file_search(c, i, paths, root_dir, false);

+                q = unit_file_search(c, i, paths, root_dir, false, true);

                 if (q == -ENOENT) {

                         /* do nothing */

                 } else if (q < 0) {

@@ -1489,6 +1496,83 @@ static int install_context_mark_for_removal(

         return r;

 }

+int unit_file_add_dependency(

+                UnitFileScope scope,

+                bool runtime,

+                const char *root_dir,

+                char **files,

+                char *target,

+                UnitDependency dep,

+                bool force,

+                UnitFileChange **changes,

+                unsigned *n_changes) {

+

+        _cleanup_lookup_paths_free_ LookupPaths paths = {};

+        _cleanup_(install_context_done) InstallContext c = {};

+        _cleanup_free_ char *config_path = NULL;

+        char **i;

+        int r;

+        InstallInfo *info;

+

+        assert(scope >= 0);

+        assert(scope < _UNIT_FILE_SCOPE_MAX);

+

+        r = lookup_paths_init_from_scope(&paths, scope, root_dir);

+        if (r < 0)

+                return r;

+

+        r = get_config_path(scope, runtime, root_dir, &config_path);

+        if (r < 0)

+                return r;

+

+        STRV_FOREACH(i, files) {

+                UnitFileState state;

+

+                state = unit_file_get_state(scope, root_dir, *i);

+                if (state < 0) {

+                        log_error("Failed to get unit file state for %s: %s", *i, strerror(-state));

+                        return state;

+                }

+

+                if (state == UNIT_FILE_MASKED || state == UNIT_FILE_MASKED_RUNTIME) {

+                        log_error("Failed to enable unit: Unit %s is masked", *i);

+                        return -ENOTSUP;

+                }

+

+                r = install_info_add_auto(&c, *i);

+                if (r < 0)

+                        return r;

+        }

+

+        while ((info = hashmap_first(c.will_install))) {

+                r = hashmap_ensure_allocated(&c.have_installed, &string_hash_ops);

+                if (r < 0)

+                        return r;

+

+                assert_se(hashmap_move_one(c.have_installed, c.will_install, info->name) == 0);

+

+                r = unit_file_search(&c, info, &paths, root_dir, false, false);

+                if (r < 0)

+                        return r;

+

+                if (dep == UNIT_WANTS)

+                        r = strv_extend(&info->wanted_by, target);

+                else if (dep == UNIT_REQUIRES)

+                        r = strv_extend(&info->required_by, target);

+                else

+                        r = -EINVAL;

+

+                if (r < 0)

+                        return r;

+

+                r = install_info_apply(info, &paths, config_path, root_dir, force, changes, n_changes);

+                if (r < 0)

+                        return r;

+        }

+

+        return 0;

+}

+

 int unit_file_enable(

                 UnitFileScope scope,

                 bool runtime,

@@ -1638,7 +1722,7 @@ int unit_file_set_default(

         assert_se(i = hashmap_first(c.will_install));

-        r = unit_file_search(&c, i, &paths, root_dir, false);

+        r = unit_file_search(&c, i, &paths, root_dir, false, true);

         if (r < 0)

                 return r;

diff --git a/src/shared/install.h b/src/shared/install.h

index ff16d9f681..c0b4df69d5 100644

--- a/src/shared/install.h

+++ b/src/shared/install.h

@@ -22,6 +22,7 @@

 ***/

 #include "hashmap.h"

+#include "unit-name.h"

 typedef enum UnitFileScope {

         UNIT_FILE_SYSTEM,

@@ -93,6 +94,7 @@ int unit_file_mask(UnitFileScope scope, bool runtime, const char *root_dir, char

 int unit_file_unmask(UnitFileScope scope, bool runtime, const char *root_dir, char **files, UnitFileChange **changes, unsigned *n_changes);

 int unit_file_set_default(UnitFileScope scope, const char *root_dir, const char *file, bool force, UnitFileChange **changes, unsigned *n_changes);

 int unit_file_get_default(UnitFileScope scope, const char *root_dir, char **name);

+int unit_file_add_dependency(UnitFileScope scope, bool runtime, const char *root_dir, char **files, char *target, UnitDependency dep, bool force, UnitFileChange **changes, unsigned *n_changes);

 UnitFileState unit_file_get_state(UnitFileScope scope, const char *root_dir, const char *filename);

diff --git a/src/systemctl/systemctl.c b/src/systemctl/systemctl.c

index 1c6fef484e..12175923e9 100644

--- a/src/systemctl/systemctl.c

+++ b/src/systemctl/systemctl.c

@@ -5288,6 +5288,100 @@ finish:

         return r;

 }

+static int add_dependency(sd_bus *bus, char **args) {

+        _cleanup_strv_free_ char **names = NULL;

+        _cleanup_free_ char *target = NULL;

+        const char *verb = args[0];

+        UnitDependency dep;

+        int r = 0;

+

+        if (!args[1])

+                return 0;

+

+        target = unit_name_mangle_with_suffix(args[1], MANGLE_NOGLOB, ".target");

+        if (!target)

+                return log_oom();

+

+        r = mangle_names(args+2, &names);

+        if (r < 0)

+                return r;

+

+        if (streq(verb, "add-wants"))

+                dep = UNIT_WANTS;

+        else if (streq(verb, "add-requires"))

+                dep = UNIT_REQUIRES;

+        else

+                assert_not_reached("Unknown verb");

+

+        if (!bus || avoid_bus()) {

+                UnitFileChange *changes = NULL;

+                unsigned n_changes = 0;

+

+                r = unit_file_add_dependency(arg_scope, arg_runtime, arg_root, names, target, dep, arg_force, &changes, &n_changes);

+

+                if (r < 0) {

+                        log_error("Can't add dependency: %s", strerror(-r));

+                        return r;

+                }

+

+                if (!arg_quiet)

+                        dump_unit_file_changes(changes, n_changes);

+

+                unit_file_changes_free(changes, n_changes);

+

+        } else {

+                _cleanup_bus_message_unref_ sd_bus_message *reply = NULL, *m = NULL;

+                _cleanup_bus_error_free_ sd_bus_error error = SD_BUS_ERROR_NULL;

+

+                r = sd_bus_message_new_method_call(

+                                bus,

+                                &m,

+                                "org.freedesktop.systemd1",

+                                "/org/freedesktop/systemd1",

+                                "org.freedesktop.systemd1.Manager",

+                                "AddDependencyUnitFiles");

+                if (r < 0)

+                        return bus_log_create_error(r);

+

+                r = sd_bus_message_append_strv(m, names);

+                if (r < 0)

+                        return bus_log_create_error(r);

+

+                r = sd_bus_message_append(m, "s", target);

+                if (r < 0)

+                        return bus_log_create_error(r);

+

+                r = sd_bus_message_append(m, "s", unit_dependency_to_string(dep));

+                if (r < 0)

+                        return bus_log_create_error(r);

+

+                r = sd_bus_message_append(m, "b", arg_runtime);

+                if (r < 0)

+                        return bus_log_create_error(r);

+

+                r = sd_bus_message_append(m, "b", arg_force);

+                if (r < 0)

+                        return bus_log_create_error(r);

+

+                r = sd_bus_call(bus, m, 0, &error, &reply);

+                if (r < 0) {

+                        log_error("Failed to execute operation: %s", bus_error_message(&error, r));

+                        return r;

+                }

+

+                r = deserialize_and_dump_unit_file_changes(reply);

+                if (r < 0)

+                        return r;

+

+                if (!arg_no_reload)

+                        r = daemon_reload(bus, args);

+                else

+                        r = 0;

+        }

+

+        return r;

+}

+

 static int preset_all(sd_bus *bus, char **args) {

         UnitFileChange *changes = NULL;

         unsigned n_changes = 0;

@@ -5533,6 +5627,10 @@ static void systemctl_help(void) {

                "  unmask NAME...                  Unmask one or more units\n"

                "  link PATH...                    Link one or more units files into\n"

                "                                  the search path\n"

+               "  add-wants TARGET NAME...        Add 'Wants' dependency for the target\n"

+               "                                  on specified one or more units\n"

+               "  add-requires TARGET NAME...     Add 'Requires' dependency for the target\n"

+               "                                  on specified one or more units\n"

                "  get-default                     Get the name of the default target\n"

                "  set-default NAME                Set the default target\n\n"

                "Machine Commands:\n"

@@ -6543,6 +6641,8 @@ static int systemctl_main(sd_bus *bus, int argc, char *argv[], int bus_error) {

                 { "get-default",           EQUAL, 1, get_default,      NOBUS },

                 { "set-property",          MORE,  3, set_property      },

                 { "is-system-running",     EQUAL, 1, is_system_running },

+                { "add-wants",             MORE,  3, add_dependency,        NOBUS },

+                { "add-requires",          MORE,  3, add_dependency,        NOBUS },

                 {}

         }, *verb = verbs;