sd-bus: allow description to be set for system/user busses (#8594)

sd_bus_open/sd_bus_open_system/sd_bus_open_user are convenient, but
don't allow the description to be set. After they return, the bus is
is already started, and sd_bus_set_description() fails with -EBUSY.
It would be possible to allow sd_bus_set_description() to update the
description "live", but messages are already emitted from sd_bus_open
functions, so it's better to allow the description to be set in
sd_bus_open/sd_bus_open_system/sd_bus_open_user.

Fixes message like:
Bus n/a: changing state UNSET → OPENING

diff --git a/src/core/dbus.c b/src/core/dbus.c
index eb9ec44f5b3711c74965db0d0852a585aa5c0d73..ace6ffa8cf3a87a04c5d10878761608b2117ea0c 100644 (file)
--- a/src/core/dbus.c
+++ b/src/core/dbus.c
@@ -895,9 +895,9 @@ int bus_init_api(Manager *m) {
                 bus = sd_bus_ref(m->system_bus);
         else {
                 if (MANAGER_IS_SYSTEM(m))
-                        r = sd_bus_open_system(&bus);
+                        r = sd_bus_open_system_with_description(&bus, "bus-api-system");
                 else
-                        r = sd_bus_open_user(&bus);
+                        r = sd_bus_open_user_with_description(&bus, "bus-api-user");
                 if (r < 0)
                         return log_error_errno(r, "Failed to connect to API bus: %m");
 
@@ -959,7 +959,7 @@ int bus_init_system(Manager *m) {
         if (MANAGER_IS_SYSTEM(m) && m->api_bus)
                 bus = sd_bus_ref(m->api_bus);
         else {
-                r = sd_bus_open_system(&bus);
+                r = sd_bus_open_system_with_description(&bus, "bus-system");
                 if (r < 0)
                         return log_error_errno(r, "Failed to connect to system bus: %m");
 

diff --git a/src/core/main.c b/src/core/main.c
index e80d4645145632fe1955e55f81bfd7b211bf4333..9e95b6f110bd58d3dc1a140376a96ed2c4d062f5 100644 (file)
--- a/src/core/main.c
+++ b/src/core/main.c
@@ -774,7 +774,6 @@ static void set_manager_settings(Manager *m) {
 }
 
 static int parse_argv(int argc, char *argv[]) {
-
         enum {
                 ARG_LOG_LEVEL = 0x100,
                 ARG_LOG_TARGET,

diff --git a/src/libsystemd/libsystemd.sym b/src/libsystemd/libsystemd.sym
index 7ff5816180d6a40006264711bcd4e71f70abf4aa..529f401a84689a0f7a1dae050111bf0615e1281d 100644 (file)
--- a/src/libsystemd/libsystemd.sym
+++ b/src/libsystemd/libsystemd.sym
@@ -555,3 +555,10 @@ global:
         sd_bus_get_n_queued_read;
         sd_bus_get_n_queued_write;
 } LIBSYSTEMD_237;
+
+LIBSYSTEMD_239 {
+global:
+        sd_bus_open_with_description;
+        sd_bus_open_user_with_description;
+        sd_bus_open_system_with_description;
+} LIBSYSTEMD_238;

diff --git a/src/libsystemd/sd-bus/sd-bus.c b/src/libsystemd/sd-bus/sd-bus.c
index 8c022fce1bec2dfc9998611f9fe8c350cc50e1c7..36c866cd8fe103d1d5c311e851db83dbcc2c7999 100644 (file)
--- a/src/libsystemd/sd-bus/sd-bus.c
+++ b/src/libsystemd/sd-bus/sd-bus.c
@@ -1220,7 +1220,7 @@ _public_ int sd_bus_start(sd_bus *bus) {
         return bus_send_hello(bus);
 }
 
-_public_ int sd_bus_open(sd_bus **ret) {
+_public_ int sd_bus_open_with_description(sd_bus **ret, const char *description) {
         const char *e;
         sd_bus *b;
         int r;
@@ -1234,17 +1234,17 @@ _public_ int sd_bus_open(sd_bus **ret) {
         e = secure_getenv("DBUS_STARTER_BUS_TYPE");
         if (e) {
                 if (streq(e, "system"))
-                        return sd_bus_open_system(ret);
+                        return sd_bus_open_system_with_description(ret, description);
                 else if (STR_IN_SET(e, "session", "user"))
-                        return sd_bus_open_user(ret);
+                        return sd_bus_open_user_with_description(ret, description);
         }
 
         e = secure_getenv("DBUS_STARTER_ADDRESS");
         if (!e) {
                 if (cg_pid_get_owner_uid(0, NULL) >= 0)
-                        return sd_bus_open_user(ret);
+                        return sd_bus_open_user_with_description(ret, description);
                 else
-                        return sd_bus_open_system(ret);
+                        return sd_bus_open_system_with_description(ret, description);
         }
 
         r = sd_bus_new(&b);
@@ -1275,6 +1275,10 @@ fail:
         return r;
 }
 
+_public_ int sd_bus_open(sd_bus **ret) {
+        return sd_bus_open_with_description(ret, NULL);
+}
+
 int bus_set_address_system(sd_bus *b) {
         const char *e;
         assert(b);
@@ -1286,7 +1290,7 @@ int bus_set_address_system(sd_bus *b) {
         return sd_bus_set_address(b, DEFAULT_SYSTEM_BUS_ADDRESS);
 }
 
-_public_ int sd_bus_open_system(sd_bus **ret) {
+_public_ int sd_bus_open_system_with_description(sd_bus **ret, const char *description) {
         sd_bus *b;
         int r;
 
@@ -1296,6 +1300,12 @@ _public_ int sd_bus_open_system(sd_bus **ret) {
         if (r < 0)
                 return r;
 
+        if (description) {
+                r = sd_bus_set_description(b, description);
+                if (r < 0)
+                        goto fail;
+        }
+
         r = bus_set_address_system(b);
         if (r < 0)
                 goto fail;
@@ -1321,6 +1331,10 @@ fail:
         return r;
 }
 
+_public_ int sd_bus_open_system(sd_bus **ret) {
+        return sd_bus_open_system_with_description(ret, NULL);
+}
+
 int bus_set_address_user(sd_bus *b) {
         const char *e;
         _cleanup_free_ char *ee = NULL, *s = NULL;
@@ -1347,7 +1361,7 @@ int bus_set_address_user(sd_bus *b) {
         return 0;
 }
 
-_public_ int sd_bus_open_user(sd_bus **ret) {
+_public_ int sd_bus_open_user_with_description(sd_bus **ret, const char *description) {
         sd_bus *b;
         int r;
 
@@ -1357,6 +1371,12 @@ _public_ int sd_bus_open_user(sd_bus **ret) {
         if (r < 0)
                 return r;
 
+        if (description) {
+                r = sd_bus_set_description(b, description);
+                if (r < 0)
+                        goto fail;
+        }
+
         r = bus_set_address_user(b);
         if (r < 0)
                 goto fail;
@@ -1381,6 +1401,10 @@ fail:
         return r;
 }
 
+_public_ int sd_bus_open_user(sd_bus **ret) {
+        return sd_bus_open_user_with_description(ret, NULL);
+}
+
 int bus_set_address_system_remote(sd_bus *b, const char *host) {
         _cleanup_free_ char *e = NULL;
         char *m = NULL, *c = NULL, *a;

diff --git a/src/libsystemd/sd-bus/test-bus-chat.c b/src/libsystemd/sd-bus/test-bus-chat.c
index bd6721946ae636d20fc111c9e027429fb2a7340f..fb748c95c8e6830bf0a80de46a15d5bb418d2b4b 100644 (file)
--- a/src/libsystemd/sd-bus/test-bus-chat.c
+++ b/src/libsystemd/sd-bus/test-bus-chat.c
@@ -64,11 +64,11 @@ static int server_init(sd_bus **_bus) {
         sd_bus *bus = NULL;
         sd_id128_t id;
         int r;
-        const char *unique;
+        const char *unique, *desc;
 
         assert_se(_bus);
 
-        r = sd_bus_open_user(&bus);
+        r = sd_bus_open_user_with_description(&bus, "my bus!");
         if (r < 0) {
                 log_error_errno(r, "Failed to connect to user bus: %m");
                 goto fail;
@@ -86,6 +86,9 @@ static int server_init(sd_bus **_bus) {
                 goto fail;
         }
 
+        r = sd_bus_get_description(bus, &desc);
+        assert_se(streq(desc, "my bus!"));
+
         log_info("Peer ID is " SD_ID128_FORMAT_STR ".", SD_ID128_FORMAT_VAL(id));
         log_info("Unique ID: %s", unique);
         log_info("Can send file handles: %i", sd_bus_can_send(bus, 'h'));

diff --git a/src/systemd/sd-bus.h b/src/systemd/sd-bus.h
index fff6798d0f3c4eaeb9b25d78491bac8c5e0deb10..90b9dd84c2ed4e8a82600b6f19317b9f7ef21c53 100644 (file)
--- a/src/systemd/sd-bus.h
+++ b/src/systemd/sd-bus.h
@@ -122,8 +122,11 @@ int sd_bus_default_user(sd_bus **ret);
 int sd_bus_default_system(sd_bus **ret);
 
 int sd_bus_open(sd_bus **ret);
+int sd_bus_open_with_description(sd_bus **ret, const char *description);
 int sd_bus_open_user(sd_bus **ret);
+int sd_bus_open_user_with_description(sd_bus **ret, const char *description);
 int sd_bus_open_system(sd_bus **ret);
+int sd_bus_open_system_with_description(sd_bus **ret, const char *description);
 int sd_bus_open_system_remote(sd_bus **ret, const char *host);
 int sd_bus_open_system_machine(sd_bus **ret, const char *machine);