1 | /* |
2 | * Copyright Andrey Semashev 2007 - 2015. |
3 | * Distributed under the Boost Software License, Version 1.0. |
4 | * (See accompanying file LICENSE_1_0.txt or copy at |
5 | * http://www.boost.org/LICENSE_1_0.txt) |
6 | */ |
7 | /*! |
8 | * \file syslog_backend.hpp |
9 | * \author Andrey Semashev |
10 | * \date 08.01.2008 |
11 | * |
12 | * The header contains implementation of a Syslog sink backend along with its setup facilities. |
13 | */ |
14 | |
15 | #ifndef BOOST_LOG_SINKS_SYSLOG_BACKEND_HPP_INCLUDED_ |
16 | #define BOOST_LOG_SINKS_SYSLOG_BACKEND_HPP_INCLUDED_ |
17 | |
18 | #include <boost/log/detail/config.hpp> |
19 | |
20 | #ifdef BOOST_HAS_PRAGMA_ONCE |
21 | #pragma once |
22 | #endif |
23 | |
24 | #ifndef BOOST_LOG_WITHOUT_SYSLOG |
25 | |
26 | #include <string> |
27 | #include <boost/log/detail/asio_fwd.hpp> |
28 | #include <boost/log/detail/light_function.hpp> |
29 | #include <boost/log/detail/parameter_tools.hpp> |
30 | #include <boost/log/sinks/basic_sink_backend.hpp> |
31 | #include <boost/log/sinks/syslog_constants.hpp> |
32 | #include <boost/log/sinks/attribute_mapping.hpp> |
33 | #include <boost/log/attributes/attribute_value_set.hpp> |
34 | #include <boost/log/keywords/facility.hpp> |
35 | #include <boost/log/keywords/use_impl.hpp> |
36 | #include <boost/log/keywords/ident.hpp> |
37 | #include <boost/log/keywords/ip_version.hpp> |
38 | #include <boost/log/detail/header.hpp> |
39 | |
40 | namespace boost { |
41 | |
42 | BOOST_LOG_OPEN_NAMESPACE |
43 | |
44 | namespace sinks { |
45 | |
46 | //! Supported IP protocol versions |
47 | enum ip_versions |
48 | { |
49 | v4, |
50 | v6 |
51 | }; |
52 | |
53 | namespace syslog { |
54 | |
55 | //! The enumeration defined the possible implementation types for the syslog backend |
56 | enum impl_types |
57 | { |
58 | #ifdef BOOST_LOG_USE_NATIVE_SYSLOG |
59 | native = 0 //!< Use native syslog API |
60 | #ifndef BOOST_LOG_NO_ASIO |
61 | , |
62 | #endif |
63 | #endif |
64 | #ifndef BOOST_LOG_NO_ASIO |
65 | udp_socket_based = 1 //!< Use UDP sockets, according to RFC3164 |
66 | #endif |
67 | }; |
68 | |
69 | /*! |
70 | * \brief Straightforward severity level mapping |
71 | * |
72 | * This type of mapping assumes that attribute with a particular name always |
73 | * provides values that map directly onto the Syslog levels. The mapping |
74 | * simply returns the extracted attribute value converted to the Syslog severity level. |
75 | */ |
76 | template< typename AttributeValueT = int > |
77 | class direct_severity_mapping : |
78 | public basic_direct_mapping< level, AttributeValueT > |
79 | { |
80 | //! Base type |
81 | typedef basic_direct_mapping< level, AttributeValueT > base_type; |
82 | |
83 | public: |
84 | /*! |
85 | * Constructor |
86 | * |
87 | * \param name Attribute name |
88 | */ |
89 | explicit direct_severity_mapping(attribute_name const& name) : |
90 | base_type(name, info) |
91 | { |
92 | } |
93 | }; |
94 | |
95 | /*! |
96 | * \brief Customizable severity level mapping |
97 | * |
98 | * The class allows to setup a custom mapping between an attribute and Syslog severity levels. |
99 | * The mapping should be initialized similarly to the standard \c map container, by using |
100 | * indexing operator and assignment. |
101 | */ |
102 | template< typename AttributeValueT = int > |
103 | class custom_severity_mapping : |
104 | public basic_custom_mapping< level, AttributeValueT > |
105 | { |
106 | //! Base type |
107 | typedef basic_custom_mapping< level, AttributeValueT > base_type; |
108 | |
109 | public: |
110 | /*! |
111 | * Constructor |
112 | * |
113 | * \param name Attribute name |
114 | */ |
115 | explicit custom_severity_mapping(attribute_name const& name) : |
116 | base_type(name, info) |
117 | { |
118 | } |
119 | }; |
120 | |
121 | } // namespace syslog |
122 | |
123 | /*! |
124 | * \brief An implementation of a syslog sink backend |
125 | * |
126 | * The backend provides support for the syslog protocol, defined in RFC3164. |
127 | * The backend sends log records to a remote host via UDP. The host name can |
128 | * be specified by calling the \c set_target_address method. By default log |
129 | * records will be sent to localhost:514. The local address can be specified |
130 | * as well, by calling the \c set_local_address method. By default syslog |
131 | * packets will be sent from any local address available. |
132 | * |
133 | * It is safe to create several sink backends with the same local addresses - |
134 | * the backends within the process will share the same socket. The same applies |
135 | * to different processes that use the syslog backends to send records from |
136 | * the same socket. However, it is not guaranteed to work if some third party |
137 | * facility is using the socket. |
138 | * |
139 | * On systems with native syslog implementation it may be preferable to utilize |
140 | * the POSIX syslog API instead of direct socket management in order to bypass |
141 | * possible security limitations that may be in action. To do so one has to pass |
142 | * the <tt>use_impl = native</tt> to the backend constructor. Note, however, |
143 | * that in that case you will only have one chance to specify syslog facility and |
144 | * process identification string - on the first native syslog backend construction. |
145 | * Other native syslog backends will ignore these parameters. |
146 | * Obviously, the \c set_local_address and \c set_target_address |
147 | * methods have no effect for native backends. Using <tt>use_impl = native</tt> |
148 | * on platforms with no native support for POSIX syslog API will have no effect. |
149 | */ |
150 | class syslog_backend : |
151 | public basic_formatted_sink_backend< char > |
152 | { |
153 | //! Base type |
154 | typedef basic_formatted_sink_backend< char > base_type; |
155 | //! Implementation type |
156 | struct implementation; |
157 | |
158 | public: |
159 | //! Character type |
160 | typedef base_type::char_type char_type; |
161 | //! String type that is used to pass message test |
162 | typedef base_type::string_type string_type; |
163 | |
164 | //! Syslog severity level mapper type |
165 | typedef boost::log::aux::light_function< syslog::level (record_view const&) > severity_mapper_type; |
166 | |
167 | private: |
168 | //! Pointer to the implementation |
169 | implementation* m_pImpl; |
170 | |
171 | public: |
172 | /*! |
173 | * Constructor. Creates a UDP socket-based backend with <tt>syslog::user</tt> facility code. |
174 | * IPv4 protocol will be used. |
175 | */ |
176 | BOOST_LOG_API syslog_backend(); |
177 | /*! |
178 | * Constructor. Creates a sink backend with the specified named parameters. |
179 | * The following named parameters are supported: |
180 | * |
181 | * \li \c facility - Specifies the facility code. If not specified, <tt>syslog::user</tt> will be used. |
182 | * \li \c use_impl - Specifies the backend implementation. Can be one of: |
183 | * \li \c native - Use the native syslog API, if available. If no native API |
184 | * is available, it is equivalent to \c udp_socket_based. |
185 | * \li \c udp_socket_based - Use the UDP socket-based implementation, conforming to |
186 | * RFC3164 protocol specification. This is the default. |
187 | * \li \c ip_version - Specifies IP protocol version to use, in case if socket-based implementation |
188 | * is used. Can be either \c v4 (the default one) or \c v6. |
189 | * \li \c ident - Process identification string. This parameter is only supported by native syslog implementation. |
190 | */ |
191 | #ifndef BOOST_LOG_DOXYGEN_PASS |
192 | BOOST_LOG_PARAMETRIZED_CONSTRUCTORS_CALL(syslog_backend, construct) |
193 | #else |
194 | template< typename... ArgsT > |
195 | explicit syslog_backend(ArgsT... const& args); |
196 | #endif |
197 | |
198 | /*! |
199 | * Destructor |
200 | */ |
201 | BOOST_LOG_API ~syslog_backend(); |
202 | |
203 | /*! |
204 | * The method installs the function object that maps application severity levels to syslog levels |
205 | */ |
206 | BOOST_LOG_API void set_severity_mapper(severity_mapper_type const& mapper); |
207 | |
208 | #if !defined(BOOST_LOG_NO_ASIO) |
209 | |
210 | /*! |
211 | * The method sets the local host name which log records will be sent from. The host name |
212 | * is resolved to obtain the final IP address. |
213 | * |
214 | * \note Does not have effect if the backend was constructed to use native syslog API |
215 | * |
216 | * \param addr The local address |
217 | * \param port The local port number |
218 | */ |
219 | BOOST_LOG_API void set_local_address(std::string const& addr, unsigned short port = 514); |
220 | /*! |
221 | * The method sets the local address which log records will be sent from. |
222 | * |
223 | * \note Does not have effect if the backend was constructed to use native syslog API |
224 | * |
225 | * \param addr The local address |
226 | * \param port The local port number |
227 | */ |
228 | BOOST_LOG_API void set_local_address(boost::asio::ip::address const& addr, unsigned short port = 514); |
229 | |
230 | /*! |
231 | * The method sets the remote host name where log records will be sent to. The host name |
232 | * is resolved to obtain the final IP address. |
233 | * |
234 | * \note Does not have effect if the backend was constructed to use native syslog API |
235 | * |
236 | * \param addr The remote host address |
237 | * \param port The port number on the remote host |
238 | */ |
239 | BOOST_LOG_API void set_target_address(std::string const& addr, unsigned short port = 514); |
240 | /*! |
241 | * The method sets the address of the remote host where log records will be sent to. |
242 | * |
243 | * \note Does not have effect if the backend was constructed to use native syslog API |
244 | * |
245 | * \param addr The remote host address |
246 | * \param port The port number on the remote host |
247 | */ |
248 | BOOST_LOG_API void set_target_address(boost::asio::ip::address const& addr, unsigned short port = 514); |
249 | |
250 | #endif // !defined(BOOST_LOG_NO_ASIO) |
251 | |
252 | /*! |
253 | * The method passes the formatted message to the syslog API or sends to a syslog server |
254 | */ |
255 | BOOST_LOG_API void consume(record_view const& rec, string_type const& formatted_message); |
256 | |
257 | private: |
258 | #ifndef BOOST_LOG_DOXYGEN_PASS |
259 | //! The method creates the backend implementation |
260 | template< typename ArgsT > |
261 | void construct(ArgsT const& args) |
262 | { |
263 | construct( |
264 | args[keywords::facility | syslog::user], |
265 | #if !defined(BOOST_LOG_NO_ASIO) |
266 | args[keywords::use_impl | syslog::udp_socket_based], |
267 | #else |
268 | args[keywords::use_impl | syslog::native], |
269 | #endif |
270 | args[keywords::ip_version | v4], |
271 | args[keywords::ident | std::string()]); |
272 | } |
273 | BOOST_LOG_API void construct( |
274 | syslog::facility facility, syslog::impl_types use_impl, ip_versions ip_version, std::string const& ident); |
275 | #endif // BOOST_LOG_DOXYGEN_PASS |
276 | }; |
277 | |
278 | } // namespace sinks |
279 | |
280 | BOOST_LOG_CLOSE_NAMESPACE // namespace log |
281 | |
282 | } // namespace boost |
283 | |
284 | #include <boost/log/detail/footer.hpp> |
285 | |
286 | #endif // BOOST_LOG_WITHOUT_SYSLOG |
287 | |
288 | #endif // BOOST_LOG_SINKS_SYSLOG_BACKEND_HPP_INCLUDED_ |
289 | |