-<?xml version='1.0'?> <!--*-nxml-*-->
+<?xml version='1.0'?> <!--*- Mode: nxml; nxml-child-indent: 2; indent-tabs-mode: nil -*-->
<!DOCTYPE refentry PUBLIC "-//OASIS//DTD DocBook XML V4.2//EN"
"http://www.oasis-open.org/docbook/xml/4.2/docbookx.dtd">
<!--
-This file is part of systemd.
+ This file is part of elogind.
-Copyright 2014 Lennart Poettering
+ Copyright 2014 Lennart Poettering
-systemd is free software; you can redistribute it and/or modify it
-under the terms of the GNU Lesser General Public License as published by
-the Free Software Foundation; either version 2.1 of the License, or
-(at your option) any later version.
+ elogind is free software; you can redistribute it and/or modify it
+ under the terms of the GNU Lesser General Public License as published by
+ the Free Software Foundation; either version 2.1 of the License, or
+ (at your option) any later version.
-systemd is distributed in the hope that it will be useful, but
-WITHOUT ANY WARRANTY; without even the implied warranty of
-MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
-Lesser General Public License for more details.
+ elogind is distributed in the hope that it will be useful, but
+ WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ Lesser General Public License for more details.
-You should have received a copy of the GNU Lesser General Public License
-along with systemd; If not, see <http://www.gnu.org/licenses/>.
+ You should have received a copy of the GNU Lesser General Public License
+ along with elogind; If not, see <http://www.gnu.org/licenses/>.
-->
-<refentry id="sd_bus_negotiate_fds" conditional="ENABLE_KDBUS">
+<refentry id="sd_bus_negotiate_fds">
<refentryinfo>
<title>sd_bus_negotiate_fds</title>
- <productname>systemd</productname>
+ <productname>elogind</productname>
<authorgroup>
<author>
<refnamediv>
<refname>sd_bus_negotiate_fds</refname>
- <refname>sd_bus_negotiate_timestamps</refname>
+ <refname>sd_bus_negotiate_timestamp</refname>
<refname>sd_bus_negotiate_creds</refname>
<refpurpose>Control feature negotiation on bus connections</refpurpose>
<refsynopsisdiv>
<funcsynopsis>
- <funcsynopsisinfo>#include <systemd/sd-bus.h></funcsynopsisinfo>
+ <funcsynopsisinfo>#include <elogind/sd-bus.h></funcsynopsisinfo>
<funcprototype>
<funcdef>int <function>sd_bus_negotiate_fds</function></funcdef>
<funcdef>int <function>sd_bus_negotiate_creds</function></funcdef>
<paramdef>sd_bus *<parameter>bus</parameter></paramdef>
<paramdef>int <parameter>b</parameter></paramdef>
+ <paramdef>uint64_t <parameter>mask</parameter></paramdef>
</funcprototype>
</funcsynopsis>
</refsynopsisdiv>
<para><function>sd_bus_negotiate_fds()</function> controls whether
file descriptor passing shall be negotiated for the specified bus
connection. It takes a bus object and a boolean, which, when true,
- enables file descriptor passing, and, when false, disables it. Note
- that not all transports and servers support file descriptor
- passing. To find out whether file descriptor passing is available
- after negotiation, use
+ enables file descriptor passing, and, when false, disables
+ it. Note that not all transports and servers support file
+ descriptor passing. In particular, networked transports generally
+ do not support file descriptor passing. To find out whether file
+ descriptor passing is available after negotiation, use
<citerefentry><refentrytitle>sd_bus_can_send</refentrytitle><manvolnum>3</manvolnum></citerefentry>
and pass <constant>SD_BUS_TYPE_UNIX_FD</constant>. Note that file
descriptor passing is always enabled for both sending and
<para><function>sd_bus_negotiate_timestamps()</function> controls
whether implicit sender timestamps shall be attached automatically
to all incoming messages. Takes a bus object and a boolean, which,
- when true, enables timestamping, and, when false, disables it. If
- this is disabled,
+ when true, enables timestamping, and, when false, disables it.
+ Use
<citerefentry><refentrytitle>sd_bus_message_get_monotonic_usec</refentrytitle><manvolnum>3</manvolnum></citerefentry>,
<citerefentry><refentrytitle>sd_bus_message_get_realtime_usec</refentrytitle><manvolnum>3</manvolnum></citerefentry>,
- <citerefentry><refentrytitle>sd_bus_message_get_seqno</refentrytitle><manvolnum>3</manvolnum></citerefentry>
- fail with <constant>-ENODATA</constant> on incoming messages. Note
- that not all transports support timestamping of messages. On local
- transports, the timestamping is applied by the kernel and cannot be
- manipulated by userspace.</para>
+ <citerefentry><refentrytitle>sd_bus_message_get_seqnum</refentrytitle><manvolnum>3</manvolnum></citerefentry>
+ to query the timestamps of incoming messages. If negotiation is
+ disabled or not supported, these calls will fail with
+ <constant>-ENODATA</constant>. Note that not all transports
+ support timestamping of messages. Specifically, timestamping is
+ only available on the kdbus transport, but not on dbus1. The
+ timestamping is applied by the kernel and cannot be manipulated by
+ userspace. By default, message timestamping is not negotiated for
+ connections.</para>
<para><function>sd_bus_negotiate_creds()</function> controls
- whether implicit sender credentials shall be attached
+ whether and which implicit sender credentials shall be attached
automatically to all incoming messages. Takes a bus object and a
- bit mask value, which controls which credential parameters are
- attached. If this is not used,
- <citerefentry><refentrytitle>sd_bus_message_get_creds</refentrytitle><manvolnum>3</manvolnum></citerefentry>
- fails with <constant>-ENODATA</constant> on incoming
- messages. Note that not all transports support attaching sender
- credentials to messages, or do not support all types of sender
- credential parameters. On local transports, the sender credentials
- are attached by the kernel and cannot be manipulated by
- userspace. By default, no sender credentials are attached.</para>
-
- <para>These functions may be called only before the connection has
- been started with
- <citerefentry><refentrytitle>sd_bus_start</refentrytitle><manvolnum>3</manvolnum></citerefentry>.</para>
+ boolean indicating whether to enable or disable the credential
+ parts encoded in the bit mask value argument. Note that not all
+ transports support attaching sender credentials to messages, or do
+ not support all types of sender credential parameters, or might
+ suppress them under certain circumstances for individual
+ messages. Specifically, implicit sender credentials on messages
+ are only fully supported on kdbus transports, and dbus1 only
+ supports <constant>SD_BUS_CREDS_UNIQUE_NAME</constant>. The sender
+ credentials are attached by the kernel and cannot be manipulated
+ by userspace, and are thus suitable for authorization
+ decisions. By default, only
+ <constant>SD_BUS_CREDS_WELL_KNOWN_NAMES</constant> and
+ <constant>SD_BUS_CREDS_UNIQUE_NAME</constant> are enabled. In
+ fact, these two credential fields are always sent along and cannot
+ be turned off.</para>
+
+ <para>The <function>sd_bus_negotiate_fds()</function> function may
+ be called only before the connection has been started with
+ <citerefentry><refentrytitle>sd_bus_start</refentrytitle><manvolnum>3</manvolnum></citerefentry>. Both
+ <function>sd_bus_negotiate_timestamp()</function> and
+ <function>sd_bus_negotiate_creds()</function> may also be called
+ after a connection has been set up. Note that, when operating on a
+ connection that is shared between multiple components of the same
+ program (for example via
+ <citerefentry><refentrytitle>sd_bus_default</refentrytitle><manvolnum>3</manvolnum></citerefentry>),
+ it is highly recommended to only enable additional per message
+ metadata fields, but never disable them again, in order not to
+ disable functionality needed by other components.</para>
</refsect1>
<refsect1>
<title>Return Value</title>
- <para>On success, these functions returns 0 or a
+ <para>On success, these functions return 0 or a
positive integer. On failure, they return a negative errno-style
error code.</para>
</refsect1>
<variablelist>
<varlistentry>
- <term><varname>-EPERM</varname></term>
+ <term><constant>-EPERM</constant></term>
<listitem><para>The bus connection has already been started.</para></listitem>
</varlistentry>
<refsect1>
<title>Notes</title>
- <para><function>sd_bus_negotiate_fs()</function> and the other
+ <para><function>sd_bus_negotiate_fds()</function> and the other
functions described here are available as a shared library, which
can be compiled and linked to with the
- <constant>libsystemd</constant> <citerefentry project='die-net'><refentrytitle>pkg-config</refentrytitle><manvolnum>1</manvolnum></citerefentry>
+ <constant>libelogind</constant> <citerefentry project='die-net'><refentrytitle>pkg-config</refentrytitle><manvolnum>1</manvolnum></citerefentry>
file.</para>
</refsect1>
<title>See Also</title>
<para>
- <citerefentry><refentrytitle>systemd</refentrytitle><manvolnum>1</manvolnum></citerefentry>,
+ <citerefentry><refentrytitle>elogind</refentrytitle><manvolnum>8</manvolnum></citerefentry>,
<citerefentry><refentrytitle>sd-bus</refentrytitle><manvolnum>3</manvolnum></citerefentry>,
<citerefentry><refentrytitle>sd_bus_start</refentrytitle><manvolnum>3</manvolnum></citerefentry>,
<citerefentry><refentrytitle>sd_bus_message_can_send</refentrytitle><manvolnum>3</manvolnum></citerefentry>,
<citerefentry><refentrytitle>sd_bus_message_get_monotonic_usec</refentrytitle><manvolnum>3</manvolnum></citerefentry>,
- <citerefentry><refentrytitle>sd_bus_message_get_creds</refentrytitle><manvolnum>3</manvolnum></citerefentry>
+ <citerefentry><refentrytitle>sd_bus_message_get_realtime_usec</refentrytitle><manvolnum>3</manvolnum></citerefentry>,
+ <citerefentry><refentrytitle>sd_bus_message_get_seqnum</refentrytitle><manvolnum>3</manvolnum></citerefentry>,
+ <citerefentry><refentrytitle>sd_bus_message_get_creds</refentrytitle><manvolnum>3</manvolnum></citerefentry>,
+ <citerefentry><refentrytitle>elogind.busname</refentrytitle><manvolnum>5</manvolnum></citerefentry>
</para>
</refsect1>