]>
Commit | Line | Data |
---|---|---|
9c920791 | 1 | <?xml version='1.0'?> <!--*-nxml-*--> |
3a54a157 | 2 | <!DOCTYPE refentry PUBLIC "-//OASIS//DTD DocBook XML V4.5//EN" |
eea10b26 | 3 | "http://www.oasis-open.org/docbook/xml/4.5/docbookx.dtd"> |
db9ecf05 | 4 | <!-- SPDX-License-Identifier: LGPL-2.1-or-later --> |
9c920791 ZJS |
5 | |
6 | <refentry id="sd_bus_message_get_type" xmlns:xi="http://www.w3.org/2001/XInclude"> | |
7 | ||
8 | <refentryinfo> | |
9 | <title>sd_bus_message_get_type</title> | |
10 | <productname>systemd</productname> | |
11 | </refentryinfo> | |
12 | ||
13 | <refmeta> | |
14 | <refentrytitle>sd_bus_message_get_type</refentrytitle> | |
15 | <manvolnum>3</manvolnum> | |
16 | </refmeta> | |
17 | ||
18 | <refnamediv> | |
19 | <refname>sd_bus_message_get_type</refname> | |
0076098b DDM |
20 | <refname>sd_bus_message_get_error</refname> |
21 | <refname>sd_bus_message_get_errno</refname> | |
68b5003b | 22 | <refname>sd_bus_message_get_creds</refname> |
9c920791 ZJS |
23 | <refname>sd_bus_message_is_signal</refname> |
24 | <refname>sd_bus_message_is_method_call</refname> | |
25 | <refname>sd_bus_message_is_method_error</refname> | |
26 | ||
68b5003b | 27 | <refpurpose>Query bus message addressing/credentials metadata</refpurpose> |
9c920791 ZJS |
28 | </refnamediv> |
29 | ||
30 | <refsynopsisdiv> | |
31 | <funcsynopsis> | |
32 | <funcsynopsisinfo>#include <systemd/sd-bus.h></funcsynopsisinfo> | |
33 | ||
34 | <funcprototype> | |
35 | <funcdef>int <function>sd_bus_message_get_type</function></funcdef> | |
0076098b | 36 | <paramdef>sd_bus_message *<parameter>m</parameter></paramdef> |
9c920791 ZJS |
37 | <paramdef>uint8_t *<parameter>type</parameter></paramdef> |
38 | </funcprototype> | |
39 | ||
0076098b DDM |
40 | <funcprototype> |
41 | <funcdef>sd_bus_error* <function>sd_bus_message_get_error</function></funcdef> | |
42 | <paramdef>sd_bus_message *<parameter>m</parameter></paramdef> | |
43 | </funcprototype> | |
44 | ||
45 | <funcprototype> | |
46 | <funcdef>int <function>sd_bus_message_get_errno</function></funcdef> | |
47 | <paramdef>sd_bus_message *<parameter>m</parameter></paramdef> | |
48 | </funcprototype> | |
49 | ||
68b5003b DDM |
50 | <funcprototype> |
51 | <funcdef>sd_bus_creds* <function>sd_bus_message_get_creds</function></funcdef> | |
52 | <paramdef>sd_bus_message *<parameter>m</parameter></paramdef> | |
53 | </funcprototype> | |
54 | ||
9c920791 ZJS |
55 | <funcprototype> |
56 | <funcdef>int <function>sd_bus_message_is_signal</function></funcdef> | |
0076098b | 57 | <paramdef>sd_bus_message *<parameter>m</parameter></paramdef> |
9c920791 ZJS |
58 | <paramdef>const char *<parameter>interface</parameter></paramdef> |
59 | <paramdef>const char *<parameter>member</parameter></paramdef> | |
60 | </funcprototype> | |
61 | ||
62 | <funcprototype> | |
63 | <funcdef>int <function>sd_bus_message_is_method_call</function></funcdef> | |
0076098b | 64 | <paramdef>sd_bus_message *<parameter>m</parameter></paramdef> |
9c920791 ZJS |
65 | <paramdef>const char *<parameter>interface</parameter></paramdef> |
66 | <paramdef>const char *<parameter>member</parameter></paramdef> | |
67 | </funcprototype> | |
68 | ||
69 | <funcprototype> | |
70 | <funcdef>int <function>sd_bus_message_is_method_error</function></funcdef> | |
0076098b | 71 | <paramdef>sd_bus_message *<parameter>m</parameter></paramdef> |
9c920791 ZJS |
72 | <paramdef>const char *<parameter>name</parameter></paramdef> |
73 | </funcprototype> | |
74 | </funcsynopsis> | |
75 | ||
76 | </refsynopsisdiv> | |
77 | ||
78 | <refsect1> | |
79 | <title>Description</title> | |
80 | ||
81 | <para><function>sd_bus_message_get_type()</function> returns the type of a message in the output | |
82 | parameter <parameter>type</parameter>, one of <constant>SD_BUS_MESSAGE_METHOD_CALL</constant>, | |
0076098b DDM |
83 | <constant>SD_BUS_MESSAGE_METHOD_RETURN</constant>, <constant>SD_BUS_MESSAGE_METHOD_ERROR</constant>, |
84 | <constant>SD_BUS_MESSAGE_SIGNAL</constant>. This type is either specified as a parameter when the message | |
85 | is created using | |
55cf7779 | 86 | <citerefentry><refentrytitle>sd_bus_message_new</refentrytitle><manvolnum>3</manvolnum></citerefentry>, |
9c920791 | 87 | or is set automatically when the message is created using |
55cf7779 ZJS |
88 | <citerefentry><refentrytitle>sd_bus_message_new_signal</refentrytitle><manvolnum>3</manvolnum></citerefentry>, |
89 | <citerefentry><refentrytitle>sd_bus_message_new_method_call</refentrytitle><manvolnum>3</manvolnum></citerefentry>, | |
90 | <citerefentry><refentrytitle>sd_bus_message_new_method_error</refentrytitle><manvolnum>3</manvolnum></citerefentry> | |
0076098b DDM |
91 | and similar functions.</para> |
92 | ||
93 | <para><function>sd_bus_message_get_error()</function> returns the error stored in the message | |
94 | <parameter>m</parameter>, if there is any. Otherwise, it returns <constant>NULL</constant>. | |
95 | <function>sd_bus_message_get_errno()</function> returns the error stored in the message | |
96 | <parameter>m</parameter> as a positive errno-style value, if there is any. Otherwise, it returns zero. | |
97 | Errors are mapped to errno values according to the default and any additional registered error mappings. | |
98 | See <citerefentry><refentrytitle>sd-bus-errors</refentrytitle><manvolnum>3</manvolnum></citerefentry> and | |
99 | <citerefentry><refentrytitle>sd_bus_error_add_map</refentrytitle><manvolnum>3</manvolnum></citerefentry>. | |
9c920791 ZJS |
100 | </para> |
101 | ||
68b5003b DDM |
102 | <para><function>sd_bus_message_get_creds()</function> returns the message credentials attached to the |
103 | message <parameter>m</parameter>. If no credentials are attached to the message, it returns | |
104 | <constant>NULL</constant>. Ownership of the credentials instance is not transferred to the caller and | |
105 | hence should not be freed.</para> | |
106 | ||
0076098b DDM |
107 | <para><function>sd_bus_message_is_signal()</function> checks if message <parameter>m</parameter> is a |
108 | signal message. If <parameter>interface</parameter> is non-null, it also checks if the message has the | |
109 | same interface set. If <parameter>member</parameter> is non-null, it also checks if the message has the | |
110 | same member set. Also see | |
55cf7779 | 111 | <citerefentry><refentrytitle>sd_bus_message_new_signal</refentrytitle><manvolnum>3</manvolnum></citerefentry>. |
0076098b | 112 | It returns true when all checks pass.</para> |
9c920791 ZJS |
113 | |
114 | <para><function>sd_bus_message_is_method_call()</function> checks if message <parameter>m</parameter> | |
0076098b DDM |
115 | is a method call message. If <parameter>interface</parameter> is non-null, it also checks if the message |
116 | has the same interface set. If <parameter>member</parameter> is non-null, it also checks if the message | |
117 | has the same member set. Also see | |
55cf7779 | 118 | <citerefentry><refentrytitle>sd_bus_message_new_method_call</refentrytitle><manvolnum>3</manvolnum></citerefentry>. |
0076098b | 119 | It returns true when all checks pass.</para> |
9c920791 ZJS |
120 | |
121 | <para><function>sd_bus_message_is_method_error()</function> checks if message <parameter>m</parameter> | |
0076098b DDM |
122 | is an error reply message. If <parameter>name</parameter> is non-null, it also checks if the message has |
123 | the same error identifier set. Also see | |
55cf7779 | 124 | <citerefentry><refentrytitle>sd_bus_message_new_method_error</refentrytitle><manvolnum>3</manvolnum></citerefentry>. |
0076098b DDM |
125 | It returns true when all checks pass.</para> |
126 | </refsect1> | |
9c920791 ZJS |
127 | |
128 | <refsect1> | |
129 | <title>Return Value</title> | |
130 | ||
68b5003b DDM |
131 | <para>On success, these functions (except <function>sd_bus_message_get_error()</function> and |
132 | <function>sd_bus_message_get_creds()</function>) return a non-negative integer. On failure, they return a | |
133 | negative errno-style error code. <function>sd_bus_message_get_errno()</function> always returns a | |
134 | non-negative integer, even on failure.</para> | |
9c920791 | 135 | |
b1de39de ZJS |
136 | <refsect2> |
137 | <title>Errors</title> | |
9c920791 | 138 | |
b1de39de | 139 | <para>Returned errors may indicate the following problems:</para> |
9c920791 | 140 | |
b1de39de ZJS |
141 | <variablelist> |
142 | <varlistentry> | |
143 | <term><constant>-EINVAL</constant></term> | |
9c920791 | 144 | |
0076098b | 145 | <listitem><para>The message parameter <parameter>m</parameter> or an output parameter is |
b1de39de ZJS |
146 | <constant>NULL</constant>.</para></listitem> |
147 | </varlistentry> | |
148 | </variablelist> | |
149 | </refsect2> | |
9c920791 ZJS |
150 | </refsect1> |
151 | ||
152 | <xi:include href="libsystemd-pkgconfig.xml" /> | |
153 | ||
69106f47 AK |
154 | <refsect1> |
155 | <title>History</title> | |
00f95506 AK |
156 | <para><function>sd_bus_message_get_type()</function>, |
157 | <function>sd_bus_message_is_signal()</function>, | |
158 | <function>sd_bus_message_is_method_call()</function>, and | |
159 | <function>sd_bus_message_is_method_error()</function> were added in version 240.</para> | |
160 | <para><function>sd_bus_message_get_error()</function>, | |
161 | <function>sd_bus_message_get_errno()</function>, and | |
162 | <function>sd_bus_message_get_creds()</function> were added in version 246.</para> | |
69106f47 AK |
163 | </refsect1> |
164 | ||
9c920791 ZJS |
165 | <refsect1> |
166 | <title>See Also</title> | |
167 | ||
13a69c12 DT |
168 | <para><simplelist type="inline"> |
169 | <member><citerefentry><refentrytitle>systemd</refentrytitle><manvolnum>1</manvolnum></citerefentry></member> | |
170 | <member><citerefentry><refentrytitle>sd-bus</refentrytitle><manvolnum>3</manvolnum></citerefentry></member> | |
171 | <member><citerefentry><refentrytitle>sd_bus_message_new</refentrytitle><manvolnum>3</manvolnum></citerefentry></member> | |
172 | <member><citerefentry><refentrytitle>sd_bus_message_set_destination</refentrytitle><manvolnum>3</manvolnum></citerefentry></member> | |
173 | <member><citerefentry><refentrytitle>sd-bus-errors</refentrytitle><manvolnum>3</manvolnum></citerefentry></member> | |
174 | <member><citerefentry><refentrytitle>sd_bus_error_add_map</refentrytitle><manvolnum>3</manvolnum></citerefentry></member> | |
175 | </simplelist></para> | |
9c920791 ZJS |
176 | </refsect1> |
177 | ||
178 | </refentry> |