1 /*
2  * libwebsockets - small server side websockets and web server implementation
3  *
4  * Copyright (C) 2010 - 2019 Andy Green <andy@warmcat.com>
5  *
6  * Permission is hereby granted, free of charge, to any person obtaining a copy
7  * of this software and associated documentation files (the "Software"), to
8  * deal in the Software without restriction, including without limitation the
9  * rights to use, copy, modify, merge, publish, distribute, sublicense, and/or
10  * sell copies of the Software, and to permit persons to whom the Software is
11  * furnished to do so, subject to the following conditions:
12  *
13  * The above copyright notice and this permission notice shall be included in
14  * all copies or substantial portions of the Software.
15  *
16  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
17  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
18  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
19  * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
20  * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
21  * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
22  * IN THE SOFTWARE.
23  */
24 
25 /** \defgroup log Logging
26  *
27  * ##Logging
28  *
29  * Lws provides flexible and filterable logging facilities, which can be
30  * used inside lws and in user code.
31  *
32  * Log categories may be individually filtered bitwise, and directed to built-in
33  * sinks for syslog-compatible logging, or a user-defined function.
34  */
35 ///@{
36 
37 enum lws_log_levels {
38 	LLL_ERR		= 1 << 0,
39 	LLL_WARN	= 1 << 1,
40 	LLL_NOTICE	= 1 << 2,
41 	LLL_INFO	= 1 << 3,
42 	LLL_DEBUG	= 1 << 4,
43 	LLL_PARSER	= 1 << 5,
44 	LLL_HEADER	= 1 << 6,
45 	LLL_EXT		= 1 << 7,
46 	LLL_CLIENT	= 1 << 8,
47 	LLL_LATENCY	= 1 << 9,
48 	LLL_USER	= 1 << 10,
49 	LLL_THREAD	= 1 << 11,
50 
51 	LLL_COUNT	= 12 /* set to count of valid flags */
52 };
53 
54 /**
55  * lwsl_timestamp: generate logging timestamp string
56  *
57  * \param level:	logging level
58  * \param p:		char * buffer to take timestamp
59  * \param len:	length of p
60  *
61  * returns length written in p
62  */
63 LWS_VISIBLE LWS_EXTERN int
64 lwsl_timestamp(int level, char *p, int len);
65 
66 #if defined(LWS_PLAT_OPTEE) && !defined(LWS_WITH_NETWORK)
67 #define _lws_log(aaa, ...) SMSG(__VA_ARGS__)
68 #else
69 LWS_VISIBLE LWS_EXTERN void _lws_log(int filter, const char *format, ...) LWS_FORMAT(2);
70 LWS_VISIBLE LWS_EXTERN void _lws_logv(int filter, const char *format, va_list vl);
71 #endif
72 
73 /* these guys are unconditionally included */
74 
75 #define lwsl_err(...) _lws_log(LLL_ERR, __VA_ARGS__)
76 #define lwsl_user(...) _lws_log(LLL_USER, __VA_ARGS__)
77 
78 #if !defined(LWS_WITH_NO_LOGS)
79 /* notice and warn are usually included by being compiled in */
80 #define lwsl_warn(...) _lws_log(LLL_WARN, __VA_ARGS__)
81 #define lwsl_notice(...) _lws_log(LLL_NOTICE, __VA_ARGS__)
82 #endif
83 /*
84  *  weaker logging can be deselected by telling CMake to build in RELEASE mode
85  *  that gets rid of the overhead of checking while keeping _warn and _err
86  *  active
87  */
88 
89 #if defined(_DEBUG)
90 #if defined(LWS_WITH_NO_LOGS)
91 /* notice, warn and log are always compiled in */
92 #define lwsl_warn(...) _lws_log(LLL_WARN, __VA_ARGS__)
93 #define lwsl_notice(...) _lws_log(LLL_NOTICE, __VA_ARGS__)
94 #endif
95 #define lwsl_info(...) _lws_log(LLL_INFO, __VA_ARGS__)
96 #define lwsl_debug(...) _lws_log(LLL_DEBUG, __VA_ARGS__)
97 #define lwsl_parser(...) _lws_log(LLL_PARSER, __VA_ARGS__)
98 #define lwsl_header(...)  _lws_log(LLL_HEADER, __VA_ARGS__)
99 #define lwsl_ext(...)  _lws_log(LLL_EXT, __VA_ARGS__)
100 #define lwsl_client(...) _lws_log(LLL_CLIENT, __VA_ARGS__)
101 #define lwsl_latency(...) _lws_log(LLL_LATENCY, __VA_ARGS__)
102 #define lwsl_thread(...) _lws_log(LLL_THREAD, __VA_ARGS__)
103 
104 #else /* no debug */
105 #if defined(LWS_WITH_NO_LOGS)
106 #define lwsl_warn(...) do {} while(0)
107 #define lwsl_notice(...) do {} while(0)
108 #endif
109 #define lwsl_info(...) do {} while(0)
110 #define lwsl_debug(...) do {} while(0)
111 #define lwsl_parser(...) do {} while(0)
112 #define lwsl_header(...) do {} while(0)
113 #define lwsl_ext(...) do {} while(0)
114 #define lwsl_client(...) do {} while(0)
115 #define lwsl_latency(...) do {} while(0)
116 #define lwsl_thread(...) do {} while(0)
117 
118 #endif
119 
120 
121 #define lwsl_hexdump_err(...) lwsl_hexdump_level(LLL_ERR, __VA_ARGS__)
122 #define lwsl_hexdump_warn(...) lwsl_hexdump_level(LLL_WARN, __VA_ARGS__)
123 #define lwsl_hexdump_notice(...) lwsl_hexdump_level(LLL_NOTICE, __VA_ARGS__)
124 #define lwsl_hexdump_info(...) lwsl_hexdump_level(LLL_INFO, __VA_ARGS__)
125 #define lwsl_hexdump_debug(...) lwsl_hexdump_level(LLL_DEBUG, __VA_ARGS__)
126 
127 /**
128  * lwsl_hexdump_level() - helper to hexdump a buffer at a selected debug level
129  *
130  * \param level: one of LLL_ constants
131  * \param vbuf: buffer start to dump
132  * \param len: length of buffer to dump
133  *
134  * If \p level is visible, does a nice hexdump -C style dump of \p vbuf for
135  * \p len bytes.  This can be extremely convenient while debugging.
136  */
137 LWS_VISIBLE LWS_EXTERN void
138 lwsl_hexdump_level(int level, const void *vbuf, size_t len);
139 
140 /**
141  * lwsl_hexdump() - helper to hexdump a buffer (DEBUG builds only)
142  *
143  * \param buf: buffer start to dump
144  * \param len: length of buffer to dump
145  *
146  * Calls through to lwsl_hexdump_level(LLL_DEBUG, ... for compatability.
147  * It's better to use lwsl_hexdump_level(level, ... directly so you can control
148  * the visibility.
149  */
150 LWS_VISIBLE LWS_EXTERN void
151 lwsl_hexdump(const void *buf, size_t len);
152 
153 /**
154  * lws_is_be() - returns nonzero if the platform is Big Endian
155  */
lws_is_be(void)156 static LWS_INLINE int lws_is_be(void) {
157 	const int probe = ~0xff;
158 
159 	return *(const char *)&probe;
160 }
161 
162 /**
163  * lws_set_log_level() - Set the logging bitfield
164  * \param level:	OR together the LLL_ debug contexts you want output from
165  * \param log_emit_function:	NULL to leave it as it is, or a user-supplied
166  *			function to perform log string emission instead of
167  *			the default stderr one.
168  *
169  *	log level defaults to "err", "warn" and "notice" contexts enabled and
170  *	emission on stderr.  If stderr is a tty (according to isatty()) then
171  *	the output is coloured according to the log level using ANSI escapes.
172  */
173 LWS_VISIBLE LWS_EXTERN void
174 lws_set_log_level(int level,
175 		  void (*log_emit_function)(int level, const char *line));
176 
177 /**
178  * lwsl_emit_syslog() - helper log emit function writes to system log
179  *
180  * \param level: one of LLL_ log level indexes
181  * \param line: log string
182  *
183  * You use this by passing the function pointer to lws_set_log_level(), to set
184  * it as the log emit function, it is not called directly.
185  */
186 LWS_VISIBLE LWS_EXTERN void
187 lwsl_emit_syslog(int level, const char *line);
188 
189 /**
190  * lwsl_emit_stderr() - helper log emit function writes to stderr
191  *
192  * \param level: one of LLL_ log level indexes
193  * \param line: log string
194  *
195  * You use this by passing the function pointer to lws_set_log_level(), to set
196  * it as the log emit function, it is not called directly.
197  *
198  * It prepends a system timestamp like [2018/11/13 07:41:57:3989]
199  *
200  * If stderr is a tty, then ansi colour codes are added.
201  */
202 LWS_VISIBLE LWS_EXTERN void
203 lwsl_emit_stderr(int level, const char *line);
204 
205 /**
206  * lwsl_emit_stderr_notimestamp() - helper log emit function writes to stderr
207  *
208  * \param level: one of LLL_ log level indexes
209  * \param line: log string
210  *
211  * You use this by passing the function pointer to lws_set_log_level(), to set
212  * it as the log emit function, it is not called directly.
213  *
214  * If stderr is a tty, then ansi colour codes are added.
215  */
216 LWS_VISIBLE LWS_EXTERN void
217 lwsl_emit_stderr_notimestamp(int level, const char *line);
218 
219 /**
220  * lwsl_visible() - returns true if the log level should be printed
221  *
222  * \param level: one of LLL_ log level indexes
223  *
224  * This is useful if you have to do work to generate the log content, you
225  * can skip the work if the log level used to print it is not actually
226  * enabled at runtime.
227  */
228 LWS_VISIBLE LWS_EXTERN int
229 lwsl_visible(int level);
230 
231 ///@}
232