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diff --git a/man/sd_bus_negotiate_fds.xml b/man/sd_bus_negotiate_fds.xml new file mode 100644 index 0000000..d7d3a51 --- /dev/null +++ b/man/sd_bus_negotiate_fds.xml @@ -0,0 +1,177 @@ +<?xml version='1.0'?> +<!DOCTYPE refentry PUBLIC "-//OASIS//DTD DocBook XML V4.5//EN" + "http://www.oasis-open.org/docbook/xml/4.2/docbookx.dtd"> +<!-- SPDX-License-Identifier: LGPL-2.1-or-later --> + +<refentry id="sd_bus_negotiate_fds" xmlns:xi="http://www.w3.org/2001/XInclude"> + + <refentryinfo> + <title>sd_bus_negotiate_fds</title> + <productname>systemd</productname> + </refentryinfo> + + <refmeta> + <refentrytitle>sd_bus_negotiate_fds</refentrytitle> + <manvolnum>3</manvolnum> + </refmeta> + + <refnamediv> + <refname>sd_bus_negotiate_fds</refname> + <refname>sd_bus_negotiate_timestamp</refname> + <refname>sd_bus_negotiate_creds</refname> + <refname>sd_bus_get_creds_mask</refname> + + <refpurpose>Control feature negotiation on bus connections</refpurpose> + </refnamediv> + + <refsynopsisdiv> + <funcsynopsis> + <funcsynopsisinfo>#include <systemd/sd-bus.h></funcsynopsisinfo> + + <funcprototype> + <funcdef>int <function>sd_bus_negotiate_fds</function></funcdef> + <paramdef>sd_bus *<parameter>bus</parameter></paramdef> + <paramdef>int <parameter>b</parameter></paramdef> + </funcprototype> + + <funcprototype> + <funcdef>int <function>sd_bus_negotiate_timestamp</function></funcdef> + <paramdef>sd_bus *<parameter>bus</parameter></paramdef> + <paramdef>int <parameter>b</parameter></paramdef> + </funcprototype> + + <funcprototype> + <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> + + <funcprototype> + <funcdef>int <function>sd_bus_get_creds_mask</function></funcdef> + <paramdef>sd_bus *<parameter>bus</parameter></paramdef> + <paramdef>uint64_t *<parameter>mask</parameter></paramdef> + </funcprototype> + </funcsynopsis> + </refsynopsisdiv> + + <refsect1> + <title>Description</title> + + <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. 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 receiving or for neither, but never only in one direction. By default, file + descriptor passing is negotiated for all connections.</para> + + <para><function>sd_bus_negotiate_timestamp()</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. 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_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 currently no transports support timestamping of + messages. By default, message timestamping is not negotiated for connections.</para> + + <para><function>sd_bus_negotiate_creds()</function> controls whether and which implicit sender + credentials shall be attached automatically to all incoming messages. Takes a bus object and a 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, dbus1 only supports <constant>SD_BUS_CREDS_UNIQUE_NAME</constant>. The sender credentials + are 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><function>sd_bus_get_creds_mask()</function> returns the set of sender credentials that was + negotiated to be attached to all incoming messages in <parameter>mask</parameter>. This value is an + upper boundary only. Hence, always make sure to explicitly check which credentials are attached to a + specific message before using it.</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 return a non-negative integer. On failure, they return a negative + errno-style error code.</para> + + <refsect2> + <title>Errors</title> + + <para>Returned errors may indicate the following problems:</para> + + <variablelist> + <varlistentry> + <term><constant>-EPERM</constant></term> + + <listitem><para>The bus connection has already been started.</para></listitem> + </varlistentry> + + <varlistentry> + <term><constant>-EINVAL</constant></term> + + <listitem><para>An argument is invalid.</para> + + <xi:include href="version-info.xml" xpointer="v246"/></listitem> + </varlistentry> + + <varlistentry> + <term><constant>-ENOPKG</constant></term> + + <listitem><para>The bus cannot be resolved.</para> + + <xi:include href="version-info.xml" xpointer="v246"/></listitem> + </varlistentry> + + <varlistentry> + <term><constant>-ECHILD</constant></term> + + <listitem><para>The bus was created in a different process, library or module instance.</para> + + <xi:include href="version-info.xml" xpointer="v246"/></listitem> + </varlistentry> + </variablelist> + </refsect2> + </refsect1> + + <xi:include href="libsystemd-pkgconfig.xml" /> + + <refsect1> + <title>History</title> + <para><function>sd_bus_negotiate_fds()</function>, + <function>sd_bus_negotiate_timestamp()</function>, and + <function>sd_bus_negotiate_creds()</function> were added in version 212.</para> + <para><function>sd_bus_get_creds_mask()</function> was added in version 246.</para> + </refsect1> + + <refsect1> + <title>See Also</title> + + <para> + <citerefentry><refentrytitle>systemd</refentrytitle><manvolnum>1</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_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_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> + </para> + </refsect1> + +</refentry> |