1 /* SPDX-License-Identifier: LGPL-2.1-or-later */
2 #pragma once
3
4 #include <stdarg.h>
5 #include <stdbool.h>
6 #include <stdlib.h>
7 #include <string.h>
8 #include <syslog.h>
9
10 #include "macro.h"
11
12 /* Some structures we reference but don't want to pull in headers for */
13 struct iovec;
14 struct signalfd_siginfo;
15
16 typedef enum LogTarget{
17 LOG_TARGET_CONSOLE,
18 LOG_TARGET_CONSOLE_PREFIXED,
19 LOG_TARGET_KMSG,
20 LOG_TARGET_JOURNAL,
21 LOG_TARGET_JOURNAL_OR_KMSG,
22 LOG_TARGET_SYSLOG,
23 LOG_TARGET_SYSLOG_OR_KMSG,
24 LOG_TARGET_AUTO, /* console if stderr is not journal, JOURNAL_OR_KMSG otherwise */
25 LOG_TARGET_NULL,
26 _LOG_TARGET_MAX,
27 _LOG_TARGET_INVALID = -EINVAL,
28 } LogTarget;
29
30 /* This log level disables logging completely. It can only be passed to log_set_max_level() and cannot be
31 * used a regular log level. */
32 #define LOG_NULL (LOG_EMERG - 1)
33
34 /* Note to readers: << and >> have lower precedence (are evaluated earlier) than & and | */
35 #define SYNTHETIC_ERRNO(num) (1 << 30 | (num))
36 #define IS_SYNTHETIC_ERRNO(val) ((val) >> 30 & 1)
37 #define ERRNO_VALUE(val) (abs(val) & ~(1 << 30))
38
39 /* The callback function to be invoked when syntax warnings are seen
40 * in the unit files. */
41 typedef void (*log_syntax_callback_t)(const char *unit, int level, void *userdata);
42 void set_log_syntax_callback(log_syntax_callback_t cb, void *userdata);
43
clear_log_syntax_callback(dummy_t * dummy)44 static inline void clear_log_syntax_callback(dummy_t *dummy) {
45 set_log_syntax_callback(/* cb= */ NULL, /* userdata= */ NULL);
46 }
47
48 const char *log_target_to_string(LogTarget target) _const_;
49 LogTarget log_target_from_string(const char *s) _pure_;
50 void log_set_target(LogTarget target);
51 int log_set_target_from_string(const char *e);
52 LogTarget log_get_target(void) _pure_;
53
54 void log_set_max_level(int level);
55 int log_set_max_level_from_string(const char *e);
56 int log_get_max_level(void) _pure_;
57
58 void log_set_facility(int facility);
59
60 void log_show_color(bool b);
61 bool log_get_show_color(void) _pure_;
62 void log_show_location(bool b);
63 bool log_get_show_location(void) _pure_;
64 void log_show_time(bool b);
65 bool log_get_show_time(void) _pure_;
66 void log_show_tid(bool b);
67 bool log_get_show_tid(void) _pure_;
68
69 int log_show_color_from_string(const char *e);
70 int log_show_location_from_string(const char *e);
71 int log_show_time_from_string(const char *e);
72 int log_show_tid_from_string(const char *e);
73
74 /* Functions below that open and close logs or configure logging based on the
75 * environment should not be called from library code — this is always a job
76 * for the application itself. */
77
78 assert_cc(STRLEN(__FILE__) > STRLEN(RELATIVE_SOURCE_PATH) + 1);
79 #define PROJECT_FILE (&__FILE__[STRLEN(RELATIVE_SOURCE_PATH) + 1])
80
81 int log_open(void);
82 void log_close(void);
83 void log_forget_fds(void);
84
85 void log_parse_environment_variables(void);
86 void log_parse_environment(void);
87
88 int log_dispatch_internal(
89 int level,
90 int error,
91 const char *file,
92 int line,
93 const char *func,
94 const char *object_field,
95 const char *object,
96 const char *extra,
97 const char *extra_field,
98 char *buffer);
99
100 int log_internal(
101 int level,
102 int error,
103 const char *file,
104 int line,
105 const char *func,
106 const char *format, ...) _printf_(6,7);
107
108 int log_internalv(
109 int level,
110 int error,
111 const char *file,
112 int line,
113 const char *func,
114 const char *format,
115 va_list ap) _printf_(6,0);
116
117 int log_object_internalv(
118 int level,
119 int error,
120 const char *file,
121 int line,
122 const char *func,
123 const char *object_field,
124 const char *object,
125 const char *extra_field,
126 const char *extra,
127 const char *format,
128 va_list ap) _printf_(10,0);
129
130 int log_object_internal(
131 int level,
132 int error,
133 const char *file,
134 int line,
135 const char *func,
136 const char *object_field,
137 const char *object,
138 const char *extra_field,
139 const char *extra,
140 const char *format, ...) _printf_(10,11);
141
142 int log_struct_internal(
143 int level,
144 int error,
145 const char *file,
146 int line,
147 const char *func,
148 const char *format, ...) _printf_(6,0) _sentinel_;
149
150 int log_oom_internal(
151 int level,
152 const char *file,
153 int line,
154 const char *func);
155
156 int log_format_iovec(
157 struct iovec *iovec,
158 size_t iovec_len,
159 size_t *n,
160 bool newline_separator,
161 int error,
162 const char *format,
163 va_list ap) _printf_(6, 0);
164
165 int log_struct_iovec_internal(
166 int level,
167 int error,
168 const char *file,
169 int line,
170 const char *func,
171 const struct iovec *input_iovec,
172 size_t n_input_iovec);
173
174 /* This modifies the buffer passed! */
175 int log_dump_internal(
176 int level,
177 int error,
178 const char *file,
179 int line,
180 const char *func,
181 char *buffer);
182
183 /* Logging for various assertions */
184 _noreturn_ void log_assert_failed(
185 const char *text,
186 const char *file,
187 int line,
188 const char *func);
189
190 _noreturn_ void log_assert_failed_unreachable(
191 const char *file,
192 int line,
193 const char *func);
194
195 void log_assert_failed_return(
196 const char *text,
197 const char *file,
198 int line,
199 const char *func);
200
201 #define log_dispatch(level, error, buffer) \
202 log_dispatch_internal(level, error, PROJECT_FILE, __LINE__, __func__, NULL, NULL, NULL, NULL, buffer)
203
204 /* Logging with level */
205 #define log_full_errno_zerook(level, error, ...) \
206 ({ \
207 int _level = (level), _e = (error); \
208 _e = (log_get_max_level() >= LOG_PRI(_level)) \
209 ? log_internal(_level, _e, PROJECT_FILE, __LINE__, __func__, __VA_ARGS__) \
210 : -ERRNO_VALUE(_e); \
211 _e < 0 ? _e : -ESTRPIPE; \
212 })
213
214 #if BUILD_MODE_DEVELOPER && !defined(TEST_CODE)
215 # define ASSERT_NON_ZERO(x) assert((x) != 0)
216 #else
217 # define ASSERT_NON_ZERO(x)
218 #endif
219
220 #define log_full_errno(level, error, ...) \
221 ({ \
222 int _error = (error); \
223 ASSERT_NON_ZERO(_error); \
224 log_full_errno_zerook(level, _error, __VA_ARGS__); \
225 })
226
227 #define log_full(level, fmt, ...) \
228 ({ \
229 if (BUILD_MODE_DEVELOPER) \
230 assert(!strstr(fmt, "%m")); \
231 (void) log_full_errno_zerook(level, 0, fmt, ##__VA_ARGS__); \
232 })
233
234 int log_emergency_level(void);
235
236 /* Normal logging */
237 #define log_debug(...) log_full(LOG_DEBUG, __VA_ARGS__)
238 #define log_info(...) log_full(LOG_INFO, __VA_ARGS__)
239 #define log_notice(...) log_full(LOG_NOTICE, __VA_ARGS__)
240 #define log_warning(...) log_full(LOG_WARNING, __VA_ARGS__)
241 #define log_error(...) log_full(LOG_ERR, __VA_ARGS__)
242 #define log_emergency(...) log_full(log_emergency_level(), __VA_ARGS__)
243
244 /* Logging triggered by an errno-like error */
245 #define log_debug_errno(error, ...) log_full_errno(LOG_DEBUG, error, __VA_ARGS__)
246 #define log_info_errno(error, ...) log_full_errno(LOG_INFO, error, __VA_ARGS__)
247 #define log_notice_errno(error, ...) log_full_errno(LOG_NOTICE, error, __VA_ARGS__)
248 #define log_warning_errno(error, ...) log_full_errno(LOG_WARNING, error, __VA_ARGS__)
249 #define log_error_errno(error, ...) log_full_errno(LOG_ERR, error, __VA_ARGS__)
250 #define log_emergency_errno(error, ...) log_full_errno(log_emergency_level(), error, __VA_ARGS__)
251
252 /* This logs at the specified level the first time it is called, and then
253 * logs at debug. If the specified level is debug, this logs only the first
254 * time it is called. */
255 #define log_once(level, ...) \
256 ({ \
257 if (ONCE) \
258 log_full(level, __VA_ARGS__); \
259 else if (LOG_PRI(level) != LOG_DEBUG) \
260 log_debug(__VA_ARGS__); \
261 })
262
263 #define log_once_errno(level, error, ...) \
264 ({ \
265 int _err = (error); \
266 if (ONCE) \
267 _err = log_full_errno(level, _err, __VA_ARGS__); \
268 else if (LOG_PRI(level) != LOG_DEBUG) \
269 _err = log_debug_errno(_err, __VA_ARGS__); \
270 else \
271 _err = -ERRNO_VALUE(_err); \
272 _err; \
273 })
274
275 #if LOG_TRACE
276 # define log_trace(...) log_debug(__VA_ARGS__)
277 # define log_trace_errno(...) log_debug_errno(__VA_ARGS__)
278 #else
279 # define log_trace(...) do {} while (0)
280 # define log_trace_errno(e, ...) (-ERRNO_VALUE(e))
281 #endif
282
283 /* Structured logging */
284 #define log_struct_errno(level, error, ...) \
285 log_struct_internal(level, error, PROJECT_FILE, __LINE__, __func__, __VA_ARGS__, NULL)
286 #define log_struct(level, ...) log_struct_errno(level, 0, __VA_ARGS__)
287
288 #define log_struct_iovec_errno(level, error, iovec, n_iovec) \
289 log_struct_iovec_internal(level, error, PROJECT_FILE, __LINE__, __func__, iovec, n_iovec)
290 #define log_struct_iovec(level, iovec, n_iovec) log_struct_iovec_errno(level, 0, iovec, n_iovec)
291
292 /* This modifies the buffer passed! */
293 #define log_dump(level, buffer) \
294 log_dump_internal(level, 0, PROJECT_FILE, __LINE__, __func__, buffer)
295
296 #define log_oom() log_oom_internal(LOG_ERR, PROJECT_FILE, __LINE__, __func__)
297 #define log_oom_debug() log_oom_internal(LOG_DEBUG, PROJECT_FILE, __LINE__, __func__)
298
299 bool log_on_console(void) _pure_;
300
301 /* Helper to wrap the main message in structured logging. The macro doesn't do much,
302 * except to provide visual grouping of the format string and its arguments. */
303 #if LOG_MESSAGE_VERIFICATION || defined(__COVERITY__)
304 /* Do a fake formatting of the message string to let the scanner verify the arguments against the format
305 * message. The variable will never be set to true, but we don't tell the compiler that :) */
306 extern bool _log_message_dummy;
307 # define LOG_MESSAGE(fmt, ...) "MESSAGE=%.0d" fmt, (_log_message_dummy && printf(fmt, ##__VA_ARGS__)), ##__VA_ARGS__
308 #else
309 # define LOG_MESSAGE(fmt, ...) "MESSAGE=" fmt, ##__VA_ARGS__
310 #endif
311
312 void log_received_signal(int level, const struct signalfd_siginfo *si);
313
314 /* If turned on, any requests for a log target involving "syslog" will be implicitly upgraded to the equivalent journal target */
315 void log_set_upgrade_syslog_to_journal(bool b);
316
317 /* If turned on, and log_open() is called, we'll not use STDERR_FILENO for logging ever, but rather open /dev/console */
318 void log_set_always_reopen_console(bool b);
319
320 /* If turned on, we'll open the log stream implicitly if needed on each individual log call. This is normally not
321 * desired as we want to reuse our logging streams. It is useful however */
322 void log_set_open_when_needed(bool b);
323
324 /* If turned on, then we'll never use IPC-based logging, i.e. never log to syslog or the journal. We'll only log to
325 * stderr, the console or kmsg */
326 void log_set_prohibit_ipc(bool b);
327
328 int log_dup_console(void);
329
330 int log_syntax_internal(
331 const char *unit,
332 int level,
333 const char *config_file,
334 unsigned config_line,
335 int error,
336 const char *file,
337 int line,
338 const char *func,
339 const char *format, ...) _printf_(9, 10);
340
341 int log_syntax_invalid_utf8_internal(
342 const char *unit,
343 int level,
344 const char *config_file,
345 unsigned config_line,
346 const char *file,
347 int line,
348 const char *func,
349 const char *rvalue);
350
351 #define log_syntax(unit, level, config_file, config_line, error, ...) \
352 ({ \
353 int _level = (level), _e = (error); \
354 (log_get_max_level() >= LOG_PRI(_level)) \
355 ? log_syntax_internal(unit, _level, config_file, config_line, _e, PROJECT_FILE, __LINE__, __func__, __VA_ARGS__) \
356 : -ERRNO_VALUE(_e); \
357 })
358
359 #define log_syntax_invalid_utf8(unit, level, config_file, config_line, rvalue) \
360 ({ \
361 int _level = (level); \
362 (log_get_max_level() >= LOG_PRI(_level)) \
363 ? log_syntax_invalid_utf8_internal(unit, _level, config_file, config_line, PROJECT_FILE, __LINE__, __func__, rvalue) \
364 : -EINVAL; \
365 })
366
367 #define DEBUG_LOGGING _unlikely_(log_get_max_level() >= LOG_DEBUG)
368
369 void log_setup(void);
370