shaba/systemd-stable
1
1
Fork 0
mirror of https://github.com/systemd/systemd-stable.git synced 2025-01-11 05:17:44 +03:00
Code

sd-bus: convenience functions to emit a signal to a destination (#25123)

Browse Source 
* sd-bus: convenience functions to emit a signal to a destination
This commit is contained in:
Erik Moqvist 2022-10-31 21:11:48 +01:00 committed by GitHub
parent a0961675d3
commit 85bc6b0549
No known key found for this signature in database
GPG Key ID: 4AEE18F83AFDEB23
8 changed files with 138 additions and 4 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

3
man/sd-bus.xml
View File

@ -68,6 +68,8 @@
<citerefentry><refentrytitle>sd_bus_emit_properties_changed_strv</refentrytitle><manvolnum>3</manvolnum></citerefentry>,
<citerefentry><refentrytitle>sd_bus_emit_signal</refentrytitle><manvolnum>3</manvolnum></citerefentry>,
<citerefentry><refentrytitle>sd_bus_emit_signalv</refentrytitle><manvolnum>3</manvolnum></citerefentry>,
<citerefentry><refentrytitle>sd_bus_emit_signal_to</refentrytitle><manvolnum>3</manvolnum></citerefentry>,
<citerefentry><refentrytitle>sd_bus_emit_signal_tov</refentrytitle><manvolnum>3</manvolnum></citerefentry>,
<citerefentry><refentrytitle>sd-bus-errors</refentrytitle><manvolnum>3</manvolnum></citerefentry>,
<citerefentry><refentrytitle>sd_bus_error</refentrytitle><manvolnum>3</manvolnum></citerefentry>,
<citerefentry><refentrytitle>sd_bus_error_add_map</refentrytitle><manvolnum>3</manvolnum></citerefentry>,
@ -122,6 +124,7 @@
<citerefentry><refentrytitle>sd_bus_message_new_method_call</refentrytitle><manvolnum>3</manvolnum></citerefentry>,
<citerefentry><refentrytitle>sd_bus_message_new_method_error</refentrytitle><manvolnum>3</manvolnum></citerefentry>,
<citerefentry><refentrytitle>sd_bus_message_new_signal</refentrytitle><manvolnum>3</manvolnum></citerefentry>,
<citerefentry><refentrytitle>sd_bus_message_new_signal_to</refentrytitle><manvolnum>3</manvolnum></citerefentry>,
<citerefentry><refentrytitle>sd_bus_message_open_container</refentrytitle><manvolnum>3</manvolnum></citerefentry>,
<citerefentry><refentrytitle>sd_bus_message_peek_type</refentrytitle><manvolnum>3</manvolnum></citerefentry>,
<citerefentry><refentrytitle>sd_bus_message_read</refentrytitle><manvolnum>3</manvolnum></citerefentry>,

29
man/sd_bus_emit_signal.xml
View File

@ -19,6 +19,8 @@
<refnamediv>
<refname>sd_bus_emit_signal</refname>
<refname>sd_bus_emit_signalv</refname>
<refname>sd_bus_emit_signal_to</refname>
<refname>sd_bus_emit_signal_tov</refname>
<refname>sd_bus_emit_interfaces_added</refname>
<refname>sd_bus_emit_interfaces_added_strv</refname>
<refname>sd_bus_emit_interfaces_removed</refname>
@ -55,6 +57,28 @@
<paramdef>va_list <parameter>ap</parameter></paramdef>
</funcprototype>
<funcprototype>
<funcdef>int <function>sd_bus_emit_signal_to</function></funcdef>
<paramdef>sd_bus *<parameter>bus</parameter></paramdef>
<paramdef>const char *<parameter>destination</parameter></paramdef>
<paramdef>const char *<parameter>path</parameter></paramdef>
<paramdef>const char *<parameter>interface</parameter></paramdef>
<paramdef>const char *<parameter>member</parameter></paramdef>
<paramdef>const char *<parameter>types</parameter></paramdef>
<paramdef>...</paramdef>
</funcprototype>
<funcprototype>
<funcdef>int <function>sd_bus_emit_signal_tov</function></funcdef>
<paramdef>sd_bus *<parameter>bus</parameter></paramdef>
<paramdef>const char *<parameter>destination</parameter></paramdef>
<paramdef>const char *<parameter>path</parameter></paramdef>
<paramdef>const char *<parameter>interface</parameter></paramdef>
<paramdef>const char *<parameter>member</parameter></paramdef>
<paramdef>const char *<parameter>types</parameter></paramdef>
<paramdef>va_list <parameter>ap</parameter></paramdef>
</funcprototype>
<funcprototype>
<funcdef>int <function>sd_bus_emit_interfaces_added</function></funcdef>
<paramdef>sd_bus *<parameter>bus</parameter></paramdef>
@ -128,6 +152,11 @@
equivalent to <function>sd_bus_message_append()</function>, except that it is called with a
<literal>va_list</literal> instead of a variable number of arguments.</para>
<para><function>sd_bus_emit_signal_to()</function> and <function>sd_bus_emit_signal_tov()</function> are
identical to <function>sd_bus_emit_signal()</function> and <function>sd_bus_emit_signalv()</function>, except
that they can emit the signal to a single destination. Give <parameter>destination</parameter> as
<constant>NULL</constant> to broadcast the signal.</para>
<para><function>sd_bus_emit_interfaces_added()</function> and
<function>sd_bus_emit_interfaces_removed()</function> are used to implement the
<function>InterfacesAdded</function> and <function>InterfacesRemoved</function> signals of the

16
man/sd_bus_message_new_signal.xml
View File

@ -18,6 +18,7 @@
<refnamediv>
<refname>sd_bus_message_new_signal</refname>
<refname>sd_bus_message_new_signal_to</refname>
<refpurpose>Create a signal message</refpurpose>
</refnamediv>
@ -34,6 +35,16 @@
<paramdef>const char *<parameter>interface</parameter></paramdef>
<paramdef>const char *<parameter>member</parameter></paramdef>
</funcprototype>
<funcprototype>
<funcdef>int sd_bus_message_new_signal_to</funcdef>
<paramdef>sd_bus *<parameter>bus</parameter></paramdef>
<paramdef>sd_bus_message **<parameter>m</parameter></paramdef>
<paramdef>const char *<parameter>destination</parameter></paramdef>
<paramdef>const char *<parameter>path</parameter></paramdef>
<paramdef>const char *<parameter>interface</parameter></paramdef>
<paramdef>const char *<parameter>member</parameter></paramdef>
</funcprototype>
</funcsynopsis>
</refsynopsisdiv>
@ -49,6 +60,10 @@
for a short description of the meaning of the <parameter>path</parameter>,
<parameter>interface</parameter>, and <parameter>member</parameter> parameters.
</para>
<para><function>sd_bus_message_new_signal_to()</function> is a shorthand for creating a new bus message
to a specific destination. It's behavior is similar to calling <function>sd_bus_message_new_signal()</function>
followed by calling <citerefentry><refentrytitle>sd_bus_message_set_destination()</refentrytitle><manvolnum>3</manvolnum></citerefentry>.</para>
</refsect1>
<refsect1>
@ -115,6 +130,7 @@
<citerefentry><refentrytitle>systemd</refentrytitle><manvolnum>1</manvolnum></citerefentry>,
<citerefentry><refentrytitle>sd-bus</refentrytitle><manvolnum>3</manvolnum></citerefentry>,
<citerefentry><refentrytitle>sd_bus_emit_signal</refentrytitle><manvolnum>3</manvolnum></citerefentry>
<citerefentry><refentrytitle>sd_bus_message_set_destination</refentrytitle><manvolnum>3</manvolnum></citerefentry>
</para>
</refsect1>

7
src/libsystemd/libsystemd.sym
View File

@ -796,3 +796,10 @@ global:
sd_hwdb_new_from_path;
} LIBSYSTEMD_251;
LIBSYSTEMD_253 {
global:
sd_bus_emit_signal_to;
sd_bus_emit_signal_tov;
sd_bus_message_new_signal_to;
} LIBSYSTEMD_252;

33
src/libsystemd/sd-bus/bus-convenience.c
View File

@ -17,8 +17,9 @@ _public_ int sd_bus_message_send(sd_bus_message *reply) {
return sd_bus_send(reply->bus, reply, NULL);
}
_public_ int sd_bus_emit_signalv(
_public_ int sd_bus_emit_signal_tov(
sd_bus *bus,
const char *destination,
const char *path,
const char *interface,
const char *member,
@ -34,7 +35,7 @@ _public_ int sd_bus_emit_signalv(
if (!BUS_IS_OPEN(bus->state))
return -ENOTCONN;
r = sd_bus_message_new_signal(bus, &m, path, interface, member);
r = sd_bus_message_new_signal_to(bus, &m, destination, path, interface, member);
if (r < 0)
return r;
@ -47,6 +48,34 @@ _public_ int sd_bus_emit_signalv(
return sd_bus_send(bus, m, NULL);
}
_public_ int sd_bus_emit_signal_to(
sd_bus *bus,
const char *destination,
const char *path,
const char *interface,
const char *member,
const char *types, ...) {
va_list ap;
int r;
va_start(ap, types);
r = sd_bus_emit_signal_tov(bus, destination, path, interface, member, types, ap);
va_end(ap);
return r;
}
_public_ int sd_bus_emit_signalv(
sd_bus *bus,
const char *path,
const char *interface,
const char *member,
const char *types, va_list ap) {
return sd_bus_emit_signal_tov(bus, NULL, path, interface, member, types, ap);
}
_public_ int sd_bus_emit_signal(
sd_bus *bus,
const char *path,

20
src/libsystemd/sd-bus/bus-message.c
View File

@ -483,9 +483,10 @@ _public_ int sd_bus_message_new(
return 0;
}
_public_ int sd_bus_message_new_signal(
_public_ int sd_bus_message_new_signal_to(
sd_bus *bus,
sd_bus_message **m,
const char *destination,
const char *path,
const char *interface,
const char *member) {
@ -496,6 +497,7 @@ _public_ int sd_bus_message_new_signal(
assert_return(bus, -ENOTCONN);
assert_return(bus = bus_resolve(bus), -ENOPKG);
assert_return(bus->state != BUS_UNSET, -ENOTCONN);
assert_return(!destination || service_name_is_valid(destination), -EINVAL);
assert_return(object_path_is_valid(path), -EINVAL);
assert_return(interface_name_is_valid(interface), -EINVAL);
assert_return(member_name_is_valid(member), -EINVAL);
@ -519,10 +521,26 @@ _public_ int sd_bus_message_new_signal(
if (r < 0)
return r;
if (destination) {
r = message_append_field_string(t, BUS_MESSAGE_HEADER_DESTINATION, SD_BUS_TYPE_STRING, destination, &t->destination);
if (r < 0)
return r;
}
*m = TAKE_PTR(t);
return 0;
}
_public_ int sd_bus_message_new_signal(
sd_bus *bus,
sd_bus_message **m,
const char *path,
const char *interface,
const char *member) {
return sd_bus_message_new_signal_to(bus, m, NULL, path, interface, member);
}
_public_ int sd_bus_message_new_method_call(
sd_bus *bus,
sd_bus_message **m,

31
src/libsystemd/sd-bus/test-bus-chat.c
View File

@ -21,7 +21,10 @@
#include "util.h"
static int match_callback(sd_bus_message *m, void *userdata, sd_bus_error *ret_error) {
log_info("Match triggered! interface=%s member=%s", strna(sd_bus_message_get_interface(m)), strna(sd_bus_message_get_member(m)));
log_info("Match triggered! destination=%s interface=%s member=%s",
strna(sd_bus_message_get_destination(m)),
strna(sd_bus_message_get_interface(m)),
strna(sd_bus_message_get_member(m)));
return 0;
}
@ -95,6 +98,12 @@ static int server_init(sd_bus **_bus) {
goto fail;
}
r = sd_bus_match_signal(bus, NULL, NULL, NULL, "foo.bar", "NotifyTo", match_callback, NULL);
if (r < 0) {
log_error_errno(r, "Failed to request match: %m");
goto fail;
}
r = sd_bus_add_match(bus, NULL, "type='signal',interface='org.freedesktop.DBus',member='NameOwnerChanged'", match_callback, NULL);
if (r < 0) {
log_error_errno(r, "Failed to add match: %m");
@ -397,6 +406,26 @@ static void* client2(void *p) {
m = sd_bus_message_unref(m);
r = sd_bus_message_new_signal_to(
bus,
&m,
"org.freedesktop.systemd.test",
"/foobar",
"foo.bar",
"NotifyTo");
if (r < 0) {
log_error_errno(r, "Failed to allocate signal to: %m");
goto finish;
}
r = sd_bus_send(bus, m, NULL);
if (r < 0) {
log_error("Failed to issue signal to: %s", bus_error_message(&error, r));
goto finish;
}
m = sd_bus_message_unref(m);
r = sd_bus_message_new_method_call(
bus,
&m,

3
src/systemd/sd-bus.h
View File

@ -260,6 +260,7 @@ void* sd_bus_slot_get_current_userdata(sd_bus_slot *slot);
int sd_bus_message_new(sd_bus *bus, sd_bus_message **m, uint8_t type);
int sd_bus_message_new_signal(sd_bus *bus, sd_bus_message **m, const char *path, const char *interface, const char *member);
int sd_bus_message_new_signal_to(sd_bus *bus, sd_bus_message **m, const char *destination, const char *path, const char *interface, const char *member);
int sd_bus_message_new_method_call(sd_bus *bus, sd_bus_message **m, const char *destination, const char *path, const char *interface, const char *member);
int sd_bus_message_new_method_return(sd_bus_message *call, sd_bus_message **m);
int sd_bus_message_new_method_error(sd_bus_message *call, sd_bus_message **m, const sd_bus_error *e);
@ -379,6 +380,8 @@ int sd_bus_reply_method_errnof(sd_bus_message *call, int error, const char *form
int sd_bus_emit_signalv(sd_bus *bus, const char *path, const char *interface, const char *member, const char *types, va_list ap);
int sd_bus_emit_signal(sd_bus *bus, const char *path, const char *interface, const char *member, const char *types, ...);
int sd_bus_emit_signal_tov(sd_bus *bus, const char *destination, const char *path, const char *interface, const char *member, const char *types, va_list ap);
int sd_bus_emit_signal_to(sd_bus *bus, const char *destination, const char *path, const char *interface, const char *member, const char *types, ...);
int sd_bus_emit_properties_changed_strv(sd_bus *bus, const char *path, const char *interface, char **names);
int sd_bus_emit_properties_changed(sd_bus *bus, const char *path, const char *interface, const char *name, ...) _sd_sentinel_;