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Merge pull request #30594 from yuwata/udev-timeout-cleanups
[thirdparty/systemd.git] / src / basic / log.h
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 "list.h"
11 #include "macro.h"
12 #include "ratelimit.h"
13 #include "stdio-util.h"
14
15 /* Some structures we reference but don't want to pull in headers for */
16 struct iovec;
17 struct signalfd_siginfo;
18
19 typedef enum LogTarget{
20 LOG_TARGET_CONSOLE,
21 LOG_TARGET_CONSOLE_PREFIXED,
22 LOG_TARGET_KMSG,
23 LOG_TARGET_JOURNAL,
24 LOG_TARGET_JOURNAL_OR_KMSG,
25 LOG_TARGET_SYSLOG,
26 LOG_TARGET_SYSLOG_OR_KMSG,
27 LOG_TARGET_AUTO, /* console if stderr is not journal, JOURNAL_OR_KMSG otherwise */
28 LOG_TARGET_NULL,
29 _LOG_TARGET_MAX,
30 _LOG_TARGET_INVALID = -EINVAL,
31 } LogTarget;
32
33 /* This log level disables logging completely. It can only be passed to log_set_max_level() and cannot be
34 * used a regular log level. */
35 #define LOG_NULL (LOG_EMERG - 1)
36
37 /* Note to readers: << and >> have lower precedence (are evaluated earlier) than & and | */
38 #define SYNTHETIC_ERRNO(num) (1 << 30 | (num))
39 #define IS_SYNTHETIC_ERRNO(val) ((val) >> 30 & 1)
40 #define ERRNO_VALUE(val) (abs(val) & ~(1 << 30))
41
42 /* The callback function to be invoked when syntax warnings are seen
43 * in the unit files. */
44 typedef void (*log_syntax_callback_t)(const char *unit, int level, void *userdata);
45 void set_log_syntax_callback(log_syntax_callback_t cb, void *userdata);
46
47 static inline void clear_log_syntax_callback(dummy_t *dummy) {
48 set_log_syntax_callback(/* cb= */ NULL, /* userdata= */ NULL);
49 }
50
51 const char *log_target_to_string(LogTarget target) _const_;
52 LogTarget log_target_from_string(const char *s) _pure_;
53 void log_set_target(LogTarget target);
54 void log_set_target_and_open(LogTarget target);
55 int log_set_target_from_string(const char *e);
56 LogTarget log_get_target(void) _pure_;
57 void log_settle_target(void);
58
59 void log_set_max_level(int level);
60 int log_set_max_level_from_string(const char *e);
61 int log_get_max_level(void) _pure_;
62
63 void log_set_facility(int facility);
64
65 void log_show_color(bool b);
66 bool log_get_show_color(void) _pure_;
67 void log_show_location(bool b);
68 bool log_get_show_location(void) _pure_;
69 void log_show_time(bool b);
70 bool log_get_show_time(void) _pure_;
71 void log_show_tid(bool b);
72 bool log_get_show_tid(void) _pure_;
73
74 int log_show_color_from_string(const char *e);
75 int log_show_location_from_string(const char *e);
76 int log_show_time_from_string(const char *e);
77 int log_show_tid_from_string(const char *e);
78
79 /* Functions below that open and close logs or configure logging based on the
80 * environment should not be called from library code — this is always a job
81 * for the application itself. */
82
83 assert_cc(STRLEN(__FILE__) > STRLEN(RELATIVE_SOURCE_PATH) + 1);
84 #define PROJECT_FILE (&__FILE__[STRLEN(RELATIVE_SOURCE_PATH) + 1])
85
86 int log_open(void);
87 void log_close(void);
88 void log_forget_fds(void);
89
90 void log_parse_environment_variables(void);
91 void log_parse_environment(void);
92
93 int log_dispatch_internal(
94 int level,
95 int error,
96 const char *file,
97 int line,
98 const char *func,
99 const char *object_field,
100 const char *object,
101 const char *extra,
102 const char *extra_field,
103 char *buffer);
104
105 int log_internal(
106 int level,
107 int error,
108 const char *file,
109 int line,
110 const char *func,
111 const char *format, ...) _printf_(6,7);
112
113 int log_internalv(
114 int level,
115 int error,
116 const char *file,
117 int line,
118 const char *func,
119 const char *format,
120 va_list ap) _printf_(6,0);
121
122 int log_object_internalv(
123 int level,
124 int error,
125 const char *file,
126 int line,
127 const char *func,
128 const char *object_field,
129 const char *object,
130 const char *extra_field,
131 const char *extra,
132 const char *format,
133 va_list ap) _printf_(10,0);
134
135 int log_object_internal(
136 int level,
137 int error,
138 const char *file,
139 int line,
140 const char *func,
141 const char *object_field,
142 const char *object,
143 const char *extra_field,
144 const char *extra,
145 const char *format, ...) _printf_(10,11);
146
147 int log_struct_internal(
148 int level,
149 int error,
150 const char *file,
151 int line,
152 const char *func,
153 const char *format, ...) _printf_(6,0) _sentinel_;
154
155 int log_oom_internal(
156 int level,
157 const char *file,
158 int line,
159 const char *func);
160
161 int log_format_iovec(
162 struct iovec *iovec,
163 size_t iovec_len,
164 size_t *n,
165 bool newline_separator,
166 int error,
167 const char *format,
168 va_list ap) _printf_(6, 0);
169
170 int log_struct_iovec_internal(
171 int level,
172 int error,
173 const char *file,
174 int line,
175 const char *func,
176 const struct iovec *input_iovec,
177 size_t n_input_iovec);
178
179 /* This modifies the buffer passed! */
180 int log_dump_internal(
181 int level,
182 int error,
183 const char *file,
184 int line,
185 const char *func,
186 char *buffer);
187
188 /* Logging for various assertions */
189 _noreturn_ void log_assert_failed(
190 const char *text,
191 const char *file,
192 int line,
193 const char *func);
194
195 _noreturn_ void log_assert_failed_unreachable(
196 const char *file,
197 int line,
198 const char *func);
199
200 void log_assert_failed_return(
201 const char *text,
202 const char *file,
203 int line,
204 const char *func);
205
206 #define log_dispatch(level, error, buffer) \
207 log_dispatch_internal(level, error, PROJECT_FILE, __LINE__, __func__, NULL, NULL, NULL, NULL, buffer)
208
209 /* Logging with level */
210 #define log_full_errno_zerook(level, error, ...) \
211 ({ \
212 int _level = (level), _e = (error); \
213 _e = (log_get_max_level() >= LOG_PRI(_level)) \
214 ? log_internal(_level, _e, PROJECT_FILE, __LINE__, __func__, __VA_ARGS__) \
215 : -ERRNO_VALUE(_e); \
216 _e < 0 ? _e : -ESTRPIPE; \
217 })
218
219 #if BUILD_MODE_DEVELOPER && !defined(TEST_CODE)
220 # define ASSERT_NON_ZERO(x) assert((x) != 0)
221 #else
222 # define ASSERT_NON_ZERO(x)
223 #endif
224
225 #define log_full_errno(level, error, ...) \
226 ({ \
227 int _error = (error); \
228 ASSERT_NON_ZERO(_error); \
229 log_full_errno_zerook(level, _error, __VA_ARGS__); \
230 })
231
232 #define log_full(level, fmt, ...) \
233 ({ \
234 if (BUILD_MODE_DEVELOPER) \
235 assert(!strstr(fmt, "%m")); \
236 (void) log_full_errno_zerook(level, 0, fmt, ##__VA_ARGS__); \
237 })
238
239 int log_emergency_level(void);
240
241 /* Normal logging */
242 #define log_debug(...) log_full(LOG_DEBUG, __VA_ARGS__)
243 #define log_info(...) log_full(LOG_INFO, __VA_ARGS__)
244 #define log_notice(...) log_full(LOG_NOTICE, __VA_ARGS__)
245 #define log_warning(...) log_full(LOG_WARNING, __VA_ARGS__)
246 #define log_error(...) log_full(LOG_ERR, __VA_ARGS__)
247 #define log_emergency(...) log_full(log_emergency_level(), __VA_ARGS__)
248
249 /* Logging triggered by an errno-like error */
250 #define log_debug_errno(error, ...) log_full_errno(LOG_DEBUG, error, __VA_ARGS__)
251 #define log_info_errno(error, ...) log_full_errno(LOG_INFO, error, __VA_ARGS__)
252 #define log_notice_errno(error, ...) log_full_errno(LOG_NOTICE, error, __VA_ARGS__)
253 #define log_warning_errno(error, ...) log_full_errno(LOG_WARNING, error, __VA_ARGS__)
254 #define log_error_errno(error, ...) log_full_errno(LOG_ERR, error, __VA_ARGS__)
255 #define log_emergency_errno(error, ...) log_full_errno(log_emergency_level(), error, __VA_ARGS__)
256
257 /* This logs at the specified level the first time it is called, and then
258 * logs at debug. If the specified level is debug, this logs only the first
259 * time it is called. */
260 #define log_once(level, ...) \
261 ({ \
262 if (ONCE) \
263 log_full(level, __VA_ARGS__); \
264 else if (LOG_PRI(level) != LOG_DEBUG) \
265 log_debug(__VA_ARGS__); \
266 })
267
268 #define log_once_errno(level, error, ...) \
269 ({ \
270 int _err = (error); \
271 if (ONCE) \
272 _err = log_full_errno(level, _err, __VA_ARGS__); \
273 else if (LOG_PRI(level) != LOG_DEBUG) \
274 _err = log_debug_errno(_err, __VA_ARGS__); \
275 else \
276 _err = -ERRNO_VALUE(_err); \
277 _err; \
278 })
279
280 #if LOG_TRACE
281 # define log_trace(...) log_debug(__VA_ARGS__)
282 # define log_trace_errno(...) log_debug_errno(__VA_ARGS__)
283 #else
284 # define log_trace(...) do {} while (0)
285 # define log_trace_errno(e, ...) (-ERRNO_VALUE(e))
286 #endif
287
288 /* Structured logging */
289 #define log_struct_errno(level, error, ...) \
290 log_struct_internal(level, error, PROJECT_FILE, __LINE__, __func__, __VA_ARGS__, NULL)
291 #define log_struct(level, ...) log_struct_errno(level, 0, __VA_ARGS__)
292
293 #define log_struct_iovec_errno(level, error, iovec, n_iovec) \
294 log_struct_iovec_internal(level, error, PROJECT_FILE, __LINE__, __func__, iovec, n_iovec)
295 #define log_struct_iovec(level, iovec, n_iovec) log_struct_iovec_errno(level, 0, iovec, n_iovec)
296
297 /* This modifies the buffer passed! */
298 #define log_dump(level, buffer) \
299 log_dump_internal(level, 0, PROJECT_FILE, __LINE__, __func__, buffer)
300
301 #define log_oom() log_oom_internal(LOG_ERR, PROJECT_FILE, __LINE__, __func__)
302 #define log_oom_debug() log_oom_internal(LOG_DEBUG, PROJECT_FILE, __LINE__, __func__)
303 #define log_oom_warning() log_oom_internal(LOG_WARNING, PROJECT_FILE, __LINE__, __func__)
304
305 bool log_on_console(void) _pure_;
306
307 /* Helper to wrap the main message in structured logging. The macro doesn't do much,
308 * except to provide visual grouping of the format string and its arguments. */
309 #if LOG_MESSAGE_VERIFICATION || defined(__COVERITY__)
310 /* Do a fake formatting of the message string to let the scanner verify the arguments against the format
311 * message. The variable will never be set to true, but we don't tell the compiler that :) */
312 extern bool _log_message_dummy;
313 # define LOG_MESSAGE(fmt, ...) "MESSAGE=%.0d" fmt, (_log_message_dummy && printf(fmt, ##__VA_ARGS__)), ##__VA_ARGS__
314 #else
315 # define LOG_MESSAGE(fmt, ...) "MESSAGE=" fmt, ##__VA_ARGS__
316 #endif
317
318 void log_received_signal(int level, const struct signalfd_siginfo *si);
319
320 /* If turned on, any requests for a log target involving "syslog" will be implicitly upgraded to the equivalent journal target */
321 void log_set_upgrade_syslog_to_journal(bool b);
322
323 /* If turned on, and log_open() is called, we'll not use STDERR_FILENO for logging ever, but rather open /dev/console */
324 void log_set_always_reopen_console(bool b);
325
326 /* If turned on, we'll open the log stream implicitly if needed on each individual log call. This is normally not
327 * desired as we want to reuse our logging streams. It is useful however */
328 void log_set_open_when_needed(bool b);
329
330 /* 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
331 * stderr, the console or kmsg */
332 void log_set_prohibit_ipc(bool b);
333
334 void log_set_assert_return_is_critical(bool b);
335 bool log_get_assert_return_is_critical(void) _pure_;
336
337 int log_dup_console(void);
338
339 int log_syntax_internal(
340 const char *unit,
341 int level,
342 const char *config_file,
343 unsigned config_line,
344 int error,
345 const char *file,
346 int line,
347 const char *func,
348 const char *format, ...) _printf_(9, 10);
349
350 int log_syntax_invalid_utf8_internal(
351 const char *unit,
352 int level,
353 const char *config_file,
354 unsigned config_line,
355 const char *file,
356 int line,
357 const char *func,
358 const char *rvalue);
359
360 #define log_syntax(unit, level, config_file, config_line, error, ...) \
361 ({ \
362 int _level = (level), _e = (error); \
363 (log_get_max_level() >= LOG_PRI(_level)) \
364 ? log_syntax_internal(unit, _level, config_file, config_line, _e, PROJECT_FILE, __LINE__, __func__, __VA_ARGS__) \
365 : -ERRNO_VALUE(_e); \
366 })
367
368 #define log_syntax_invalid_utf8(unit, level, config_file, config_line, rvalue) \
369 ({ \
370 int _level = (level); \
371 (log_get_max_level() >= LOG_PRI(_level)) \
372 ? log_syntax_invalid_utf8_internal(unit, _level, config_file, config_line, PROJECT_FILE, __LINE__, __func__, rvalue) \
373 : -EINVAL; \
374 })
375
376 #define DEBUG_LOGGING _unlikely_(log_get_max_level() >= LOG_DEBUG)
377
378 void log_setup(void);
379
380 typedef struct LogRateLimit {
381 int error;
382 int level;
383 RateLimit ratelimit;
384 } LogRateLimit;
385
386 #define log_ratelimit_internal(_level, _error, _ratelimit, _format, _file, _line, _func, ...) \
387 ({ \
388 int _log_ratelimit_error = (_error); \
389 int _log_ratelimit_level = (_level); \
390 static LogRateLimit _log_ratelimit = { \
391 .ratelimit = (_ratelimit), \
392 }; \
393 unsigned _num_dropped_errors = ratelimit_num_dropped(&_log_ratelimit.ratelimit); \
394 if (_log_ratelimit_error != _log_ratelimit.error || _log_ratelimit_level != _log_ratelimit.level) { \
395 ratelimit_reset(&_log_ratelimit.ratelimit); \
396 _log_ratelimit.error = _log_ratelimit_error; \
397 _log_ratelimit.level = _log_ratelimit_level; \
398 } \
399 if (log_get_max_level() == LOG_DEBUG || ratelimit_below(&_log_ratelimit.ratelimit)) \
400 _log_ratelimit_error = _num_dropped_errors > 0 \
401 ? log_internal(_log_ratelimit_level, _log_ratelimit_error, _file, _line, _func, _format " (Dropped %u similar message(s))", ##__VA_ARGS__, _num_dropped_errors) \
402 : log_internal(_log_ratelimit_level, _log_ratelimit_error, _file, _line, _func, _format, ##__VA_ARGS__); \
403 _log_ratelimit_error; \
404 })
405
406 #define log_ratelimit_full_errno(level, error, _ratelimit, format, ...) \
407 ({ \
408 int _level = (level), _e = (error); \
409 _e = (log_get_max_level() >= LOG_PRI(_level)) \
410 ? log_ratelimit_internal(_level, _e, _ratelimit, format, PROJECT_FILE, __LINE__, __func__, ##__VA_ARGS__) \
411 : -ERRNO_VALUE(_e); \
412 _e < 0 ? _e : -ESTRPIPE; \
413 })
414
415 #define log_ratelimit_full(level, _ratelimit, format, ...) \
416 log_ratelimit_full_errno(level, 0, _ratelimit, format, ##__VA_ARGS__)
417
418 /* Normal logging */
419 #define log_ratelimit_info(...) log_ratelimit_full(LOG_INFO, __VA_ARGS__)
420 #define log_ratelimit_notice(...) log_ratelimit_full(LOG_NOTICE, __VA_ARGS__)
421 #define log_ratelimit_warning(...) log_ratelimit_full(LOG_WARNING, __VA_ARGS__)
422 #define log_ratelimit_error(...) log_ratelimit_full(LOG_ERR, __VA_ARGS__)
423 #define log_ratelimit_emergency(...) log_ratelimit_full(log_emergency_level(), __VA_ARGS__)
424
425 /* Logging triggered by an errno-like error */
426 #define log_ratelimit_info_errno(error, ...) log_ratelimit_full_errno(LOG_INFO, error, __VA_ARGS__)
427 #define log_ratelimit_notice_errno(error, ...) log_ratelimit_full_errno(LOG_NOTICE, error, __VA_ARGS__)
428 #define log_ratelimit_warning_errno(error, ...) log_ratelimit_full_errno(LOG_WARNING, error, __VA_ARGS__)
429 #define log_ratelimit_error_errno(error, ...) log_ratelimit_full_errno(LOG_ERR, error, __VA_ARGS__)
430 #define log_ratelimit_emergency_errno(error, ...) log_ratelimit_full_errno(log_emergency_level(), error, __VA_ARGS__)
431
432 const char *_log_set_prefix(const char *prefix, bool force);
433 static inline const char *_log_unset_prefixp(const char **p) {
434 assert(p);
435 _log_set_prefix(*p, true);
436 return NULL;
437 }
438
439 #define LOG_SET_PREFIX(prefix) \
440 _cleanup_(_log_unset_prefixp) _unused_ const char *CONCATENATE(_cleanup_log_unset_prefix_, UNIQ) = _log_set_prefix(prefix, false);
441
442 /*
443 * The log context allows attaching extra metadata to log messages written to the journal via log.h. We keep
444 * track of a thread local log context onto which we can push extra metadata fields that should be logged.
445 *
446 * LOG_CONTEXT_PUSH() will add the provided field to the log context and will remove it again when the
447 * current block ends. LOG_CONTEXT_PUSH_STRV() will do the same but for all fields in the given strv.
448 * LOG_CONTEXT_PUSHF() is like LOG_CONTEXT_PUSH() but takes a format string and arguments.
449 *
450 * Using the macros is as simple as putting them anywhere inside a block to add a field to all following log
451 * messages logged from inside that block.
452 *
453 * void myfunction(...) {
454 * ...
455 *
456 * LOG_CONTEXT_PUSHF("MYMETADATA=%s", "abc");
457 *
458 * // Every journal message logged will now have the MYMETADATA=abc
459 * // field included.
460 * }
461 *
462 * One special case to note is async code, where we use callbacks that are invoked to continue processing
463 * when some event occurs. For async code, there's usually an associated "userdata" struct containing all the
464 * information associated with the async operation. In this "userdata" struct, we can store a log context
465 * allocated with log_context_new() and freed with log_context_free(). We can then add and remove fields to
466 * the `fields` member of the log context object and all those fields will be logged along with each log
467 * message.
468 */
469
470 typedef struct LogContext LogContext;
471
472 bool log_context_enabled(void);
473
474 LogContext* log_context_new(const char *key, const char *value);
475 LogContext* log_context_new_strv(char **fields, bool owned);
476 LogContext* log_context_new_iov(struct iovec *input_iovec, size_t n_input_iovec, bool owned);
477
478 /* Same as log_context_new(), but frees the given fields strv/iovec on failure. */
479 LogContext* log_context_new_strv_consume(char **fields);
480 LogContext* log_context_new_iov_consume(struct iovec *input_iovec, size_t n_input_iovec);
481
482 LogContext *log_context_ref(LogContext *c);
483 LogContext *log_context_unref(LogContext *c);
484
485 DEFINE_TRIVIAL_CLEANUP_FUNC(LogContext*, log_context_unref);
486
487 /* Returns the number of attached log context objects. */
488 size_t log_context_num_contexts(void);
489 /* Returns the number of fields in all attached log contexts. */
490 size_t log_context_num_fields(void);
491
492 #define LOG_CONTEXT_PUSH(...) \
493 LOG_CONTEXT_PUSH_STRV(STRV_MAKE(__VA_ARGS__))
494
495 #define LOG_CONTEXT_PUSHF(...) \
496 LOG_CONTEXT_PUSH(snprintf_ok((char[LINE_MAX]) {}, LINE_MAX, __VA_ARGS__))
497
498 #define _LOG_CONTEXT_PUSH_KEY_VALUE(key, value, c) \
499 _unused_ _cleanup_(log_context_unrefp) LogContext *c = log_context_new(key, value);
500
501 #define LOG_CONTEXT_PUSH_KEY_VALUE(key, value) \
502 _LOG_CONTEXT_PUSH_KEY_VALUE(key, value, UNIQ_T(c, UNIQ))
503
504 #define _LOG_CONTEXT_PUSH_STRV(strv, c) \
505 _unused_ _cleanup_(log_context_unrefp) LogContext *c = log_context_new_strv(strv, /*owned=*/ false);
506
507 #define LOG_CONTEXT_PUSH_STRV(strv) \
508 _LOG_CONTEXT_PUSH_STRV(strv, UNIQ_T(c, UNIQ))
509
510 #define _LOG_CONTEXT_PUSH_IOV(input_iovec, n_input_iovec, c) \
511 _unused_ _cleanup_(log_context_unrefp) LogContext *c = log_context_new_iov(input_iovec, n_input_iovec, /*owned=*/ false);
512
513 #define LOG_CONTEXT_PUSH_IOV(input_iovec, n_input_iovec) \
514 _LOG_CONTEXT_PUSH_IOV(input_iovec, n_input_iovec, UNIQ_T(c, UNIQ))
515
516 /* LOG_CONTEXT_CONSUME_STR()/LOG_CONTEXT_CONSUME_STRV()/LOG_CONTEXT_CONSUME_IOV() are identical to
517 * LOG_CONTEXT_PUSH_STR()/LOG_CONTEXT_PUSH_STRV()/LOG_CONTEXT_PUSH_IOV() except they take ownership of the
518 * given str/strv argument.
519 */
520
521 #define _LOG_CONTEXT_CONSUME_STR(s, c, strv) \
522 _unused_ _cleanup_strv_free_ strv = strv_new(s); \
523 if (!strv) \
524 free(s); \
525 _unused_ _cleanup_(log_context_unrefp) LogContext *c = log_context_new_strv_consume(TAKE_PTR(strv))
526
527 #define LOG_CONTEXT_CONSUME_STR(s) \
528 _LOG_CONTEXT_CONSUME_STR(s, UNIQ_T(c, UNIQ), UNIQ_T(sv, UNIQ))
529
530 #define _LOG_CONTEXT_CONSUME_STRV(strv, c) \
531 _unused_ _cleanup_(log_context_unrefp) LogContext *c = log_context_new_strv_consume(strv);
532
533 #define LOG_CONTEXT_CONSUME_STRV(strv) \
534 _LOG_CONTEXT_CONSUME_STRV(strv, UNIQ_T(c, UNIQ))
535
536 #define _LOG_CONTEXT_CONSUME_IOV(input_iovec, n_input_iovec, c) \
537 _unused_ _cleanup_(log_context_unrefp) LogContext *c = log_context_new_iov_consume(input_iovec, n_input_iovec);
538
539 #define LOG_CONTEXT_CONSUME_IOV(input_iovec, n_input_iovec) \
540 _LOG_CONTEXT_CONSUME_IOV(input_iovec, n_input_iovec, UNIQ_T(c, UNIQ))