summaryrefslogtreecommitdiff
path: root/src/libnm-systemd-shared/src/basic/log.h
blob: 1b5bc655f83939ece3cbf6ca0faccdbcb793514f (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
/* SPDX-License-Identifier: LGPL-2.1-or-later */
#pragma once

#include <stdarg.h>
#include <stdbool.h>
#include <stdlib.h>
#include <string.h>
#include <syslog.h>

#include "list.h"
#include "macro.h"
#include "ratelimit.h"
#include "stdio-util.h"

/* Some structures we reference but don't want to pull in headers for */
struct iovec;
struct signalfd_siginfo;

typedef enum LogTarget{
        LOG_TARGET_CONSOLE,
        LOG_TARGET_CONSOLE_PREFIXED,
        LOG_TARGET_KMSG,
        LOG_TARGET_JOURNAL,
        LOG_TARGET_JOURNAL_OR_KMSG,
        LOG_TARGET_SYSLOG,
        LOG_TARGET_SYSLOG_OR_KMSG,
        LOG_TARGET_AUTO, /* console if stderr is not journal, JOURNAL_OR_KMSG otherwise */
        LOG_TARGET_NULL,
        _LOG_TARGET_MAX,
        _LOG_TARGET_INVALID = -EINVAL,
} LogTarget;

/* This log level disables logging completely. It can only be passed to log_set_max_level() and cannot be
 * used a regular log level. */
#define LOG_NULL (LOG_EMERG - 1)

/* Note to readers: << and >> have lower precedence (are evaluated earlier) than & and | */
#define SYNTHETIC_ERRNO(num)                (1 << 30 | (num))
#define IS_SYNTHETIC_ERRNO(val)             ((val) >> 30 & 1)
#define ERRNO_VALUE(val)                    (abs(val) & ~(1 << 30))

/* The callback function to be invoked when syntax warnings are seen
 * in the unit files. */
typedef void (*log_syntax_callback_t)(const char *unit, int level, void *userdata);
void set_log_syntax_callback(log_syntax_callback_t cb, void *userdata);

static inline void clear_log_syntax_callback(dummy_t *dummy) {
          set_log_syntax_callback(/* cb= */ NULL, /* userdata= */ NULL);
}

const char *log_target_to_string(LogTarget target) _const_;
LogTarget log_target_from_string(const char *s) _pure_;
void log_set_target(LogTarget target);
void log_set_target_and_open(LogTarget target);
int log_set_target_from_string(const char *e);
LogTarget log_get_target(void) _pure_;
void log_settle_target(void);

void log_set_max_level(int level);
int log_set_max_level_from_string(const char *e);
#if 0 /* NM_IGNORED */
int log_get_max_level(void) _pure_;
#else /* NM_IGNORED */
static inline int
log_get_max_level(void)
{
        return 7 /* LOG_DEBUG */;
}
#endif /* NM_IGNORED */

void log_set_facility(int facility);

void log_show_color(bool b);
bool log_get_show_color(void) _pure_;
void log_show_location(bool b);
bool log_get_show_location(void) _pure_;
void log_show_time(bool b);
bool log_get_show_time(void) _pure_;
void log_show_tid(bool b);
bool log_get_show_tid(void) _pure_;

int log_show_color_from_string(const char *e);
int log_show_location_from_string(const char *e);
int log_show_time_from_string(const char *e);
int log_show_tid_from_string(const char *e);

/* Functions below that open and close logs or configure logging based on the
 * environment should not be called from library code — this is always a job
 * for the application itself. */

#if 0 /* NM_IGNORED */
assert_cc(STRLEN(__FILE__) > STRLEN(RELATIVE_SOURCE_PATH) + 1);
#define PROJECT_FILE (&__FILE__[STRLEN(RELATIVE_SOURCE_PATH) + 1])
#else /* NM_IGNORED */
#define PROJECT_FILE __FILE__
#endif /* NM_IGNORED */

int log_open(void);
void log_close(void);
void log_forget_fds(void);

void log_parse_environment_variables(void);
void log_parse_environment(void);

#if 0 /* NM_IGNORED */
int log_dispatch_internal(
                int level,
                int error,
                const char *file,
                int line,
                const char *func,
                const char *object_field,
                const char *object,
                const char *extra,
                const char *extra_field,
                char *buffer);
#endif /* NM_IGNORED */

#if 0 /* NM_IGNORED */
int log_internal(
                int level,
                int error,
                const char *file,
                int line,
                const char *func,
                const char *format, ...) _printf_(6,7);
#else /* NM_IGNORED */
#define log_internal(level, error, file, line, func, format, ...)                          \
    ({                                                                                     \
        const int        _nm_e = (error);                                                  \
        const NMLogLevel _nm_l = nm_log_level_from_syslog(LOG_PRI(level));                 \
                                                                                           \
        if (_nm_log_enabled_impl(!(NM_THREAD_SAFE_ON_MAIN_THREAD), _nm_l, LOGD_SYSTEMD)) { \
            const char *_nm_location = strrchr(("" file), '/');                            \
                                                                                           \
            _nm_log_full(_nm_location ? _nm_location + 1 : ("" file),                      \
                         (line),                                                           \
                         (func),                                                           \
                         !(NM_THREAD_SAFE_ON_MAIN_THREAD),                                 \
                         _nm_l,                                                            \
                         LOGD_SYSTEMD,                                                     \
                         _nm_e,                                                            \
                         NULL,                                                             \
                         NULL,                                                             \
                         ("%s" format),                                                    \
                         "libsystemd: ",                                                   \
                         ##__VA_ARGS__);                                                   \
        }                                                                                  \
        (_nm_e > 0 ? -_nm_e : _nm_e);                                                      \
    })
#endif /* NM_IGNORED */

#if 0 /* NM_IGNORED */
int log_internalv(
                int level,
                int error,
                const char *file,
                int line,
                const char *func,
                const char *format,
                va_list ap) _printf_(6,0);

int log_object_internalv(
                int level,
                int error,
                const char *file,
                int line,
                const char *func,
                const char *object_field,
                const char *object,
                const char *extra_field,
                const char *extra,
                const char *format,
                va_list ap) _printf_(10,0);
#endif /* NM_IGNORED */

#if 0 /* NM_IGNORED */
int log_object_internal(
                int level,
                int error,
                const char *file,
                int line,
                const char *func,
                const char *object_field,
                const char *object,
                const char *extra_field,
                const char *extra,
                const char *format, ...) _printf_(10,11);
#else /* NM_IGNORED */
#define log_object_internal(level,              \
                            error,              \
                            file,               \
                            line,               \
                            func,               \
                            object_field,       \
                            object,             \
                            extra_field,        \
                            extra,              \
                            format,             \
                            ...)                \
    ({                                          \
        const char *const _object = (object);   \
                                                \
        log_internal((level),                   \
                     (error),                   \
                     file,                      \
                     (line),                    \
                     (func),                    \
                     "%s%s" format,             \
                     _object ?: "",             \
                     _object ? ": " : "",       \
                     ##__VA_ARGS__);            \
    })
#endif /* NM_IGNORED */


#if 0 /* NM_IGNORED */
int log_struct_internal(
                int level,
                int error,
                const char *file,
                int line,
                const char *func,
                const char *format, ...) _printf_(6,0) _sentinel_;
#endif /* NM_IGNORED */

#if 0 /* NM_IGNORED */
int log_oom_internal(
                int level,
                const char *file,
                int line,
                const char *func);
#else /* NM_IGNORED */
#define log_oom_internal(level, file, line, func) \
    log_internal(level, ENOMEM, file, line, func, "Out of memory.")
#endif /* NM_IGNORED */

#if 0 /* NM_IGNORED */
int log_format_iovec(
                struct iovec *iovec,
                size_t iovec_len,
                size_t *n,
                bool newline_separator,
                int error,
                const char *format,
                va_list ap) _printf_(6, 0);

int log_struct_iovec_internal(
                int level,
                int error,
                const char *file,
                int line,
                const char *func,
                const struct iovec *input_iovec,
                size_t n_input_iovec);

/* This modifies the buffer passed! */
int log_dump_internal(
                int level,
                int error,
                const char *file,
                int line,
                const char *func,
                char *buffer);
#endif /* NM_IGNORED */

/* Logging for various assertions */
#if 0 /* NM_IGNORED */
_noreturn_ void log_assert_failed(
                const char *text,
                const char *file,
                int line,
                const char *func);
#else /* NM_IGNORED */
#define log_assert_failed(text, file, line, func)                                \
    G_STMT_START                                                                 \
    {                                                                            \
        log_internal(LOG_CRIT,                                                   \
                     0,                                                          \
                     file,                                                       \
                     line,                                                       \
                     func,                                                       \
                     "Assertion '%s' failed at %s:%u, function %s(). Aborting.", \
                     text,                                                       \
                     file,                                                       \
                     line,                                                       \
                     func);                                                      \
        g_assert_not_reached();                                                  \
    }                                                                            \
    G_STMT_END
#endif /* NM_IGNORED */

#if 0 /* NM_IGNORED */
_noreturn_ void log_assert_failed_unreachable(
                const char *file,
                int line,
                const char *func);
#else /* NM_IGNORED */
#define log_assert_failed_unreachable(file, line, func)                               \
    G_STMT_START                                                                      \
    {                                                                                 \
        log_internal(LOG_CRIT,                                                        \
                     0,                                                               \
                     file,                                                            \
                     line,                                                            \
                     func,                                                            \
                     "Code should not be reached at %s:%u, function %s(). Aborting.", \
                     file,                                                            \
                     line,                                                            \
                     func);                                                           \
        g_assert_not_reached();                                                       \
    }                                                                                 \
    G_STMT_END
#endif /* NM_IGNORED */

#if 0 /* NM_IGNORED */
void log_assert_failed_return(
                const char *text,
                const char *file,
                int line,
                const char *func);
#else /* NM_IGNORED */
#define log_assert_failed_return(text, file, line, func)                         \
    ({                                                                           \
        log_internal(LOG_DEBUG,                                                  \
                     0,                                                          \
                     file,                                                       \
                     line,                                                       \
                     func,                                                       \
                     "Assertion '%s' failed at %s:%u, function %s(). Ignoring.", \
                     text,                                                       \
                     file,                                                       \
                     line,                                                       \
                     func);                                                      \
        g_return_if_fail_warning(G_LOG_DOMAIN, G_STRFUNC, text);                 \
        (void) 0;                                                                \
    })
#endif /* NM_IGNORED */

#if 0 /* NM_IGNORED */
#define log_dispatch(level, error, buffer)                              \
        log_dispatch_internal(level, error, PROJECT_FILE, __LINE__, __func__, NULL, NULL, NULL, NULL, buffer)
#endif /* NM_IGNORED */

/* Logging with level */
#define log_full_errno_zerook(level, error, ...)                        \
        ({                                                              \
                int _level = (level), _e = (error);                     \
                _e = (log_get_max_level() >= LOG_PRI(_level))           \
                        ? log_internal(_level, _e, PROJECT_FILE, __LINE__, __func__, __VA_ARGS__) \
                        : -ERRNO_VALUE(_e);                             \
                _e < 0 ? _e : -ESTRPIPE;                                \
        })

#if BUILD_MODE_DEVELOPER && !defined(TEST_CODE)
#  define ASSERT_NON_ZERO(x) assert((x) != 0)
#else
#  define ASSERT_NON_ZERO(x)
#endif

#define log_full_errno(level, error, ...)                               \
        ({                                                              \
                int _error = (error);                                   \
                ASSERT_NON_ZERO(_error);                                \
                log_full_errno_zerook(level, _error, __VA_ARGS__);      \
        })

#define log_full(level, fmt, ...)                                      \
        ({                                                             \
                if (BUILD_MODE_DEVELOPER)                              \
                        assert(!strstr(fmt, "%m"));                    \
                (void) log_full_errno_zerook(level, 0, fmt, ##__VA_ARGS__); \
        })

int log_emergency_level(void);

/* Normal logging */
#define log_debug(...)     log_full(LOG_DEBUG,   __VA_ARGS__)
#define log_info(...)      log_full(LOG_INFO,    __VA_ARGS__)
#define log_notice(...)    log_full(LOG_NOTICE,  __VA_ARGS__)
#define log_warning(...)   log_full(LOG_WARNING, __VA_ARGS__)
#define log_error(...)     log_full(LOG_ERR,     __VA_ARGS__)
#define log_emergency(...) log_full(log_emergency_level(), __VA_ARGS__)

/* Logging triggered by an errno-like error */
#define log_debug_errno(error, ...)     log_full_errno(LOG_DEBUG,   error, __VA_ARGS__)
#define log_info_errno(error, ...)      log_full_errno(LOG_INFO,    error, __VA_ARGS__)
#define log_notice_errno(error, ...)    log_full_errno(LOG_NOTICE,  error, __VA_ARGS__)
#define log_warning_errno(error, ...)   log_full_errno(LOG_WARNING, error, __VA_ARGS__)
#define log_error_errno(error, ...)     log_full_errno(LOG_ERR,     error, __VA_ARGS__)
#define log_emergency_errno(error, ...) log_full_errno(log_emergency_level(), error, __VA_ARGS__)

/* This logs at the specified level the first time it is called, and then
 * logs at debug. If the specified level is debug, this logs only the first
 * time it is called. */
#define log_once(level, ...)                                             \
        ({                                                               \
                if (ONCE)                                                \
                        log_full(level, __VA_ARGS__);                    \
                else if (LOG_PRI(level) != LOG_DEBUG)                    \
                        log_debug(__VA_ARGS__);                          \
        })

#define log_once_errno(level, error, ...)                                \
        ({                                                               \
                int _err = (error);                                      \
                if (ONCE)                                                \
                        _err = log_full_errno(level, _err, __VA_ARGS__); \
                else if (LOG_PRI(level) != LOG_DEBUG)                    \
                        _err = log_debug_errno(_err, __VA_ARGS__);       \
                else                                                     \
                        _err = -ERRNO_VALUE(_err);                       \
                _err;                                                    \
        })

#if LOG_TRACE
#  define log_trace(...)          log_debug(__VA_ARGS__)
#  define log_trace_errno(...)    log_debug_errno(__VA_ARGS__)
#else
#  define log_trace(...)          do {} while (0)
#  define log_trace_errno(e, ...) (-ERRNO_VALUE(e))
#endif

/* Structured logging */
#define log_struct_errno(level, error, ...)                             \
        log_struct_internal(level, error, PROJECT_FILE, __LINE__, __func__, __VA_ARGS__, NULL)
#define log_struct(level, ...) log_struct_errno(level, 0, __VA_ARGS__)

#define log_struct_iovec_errno(level, error, iovec, n_iovec)            \
        log_struct_iovec_internal(level, error, PROJECT_FILE, __LINE__, __func__, iovec, n_iovec)
#define log_struct_iovec(level, iovec, n_iovec) log_struct_iovec_errno(level, 0, iovec, n_iovec)

/* This modifies the buffer passed! */
#define log_dump(level, buffer)                                         \
        log_dump_internal(level, 0, PROJECT_FILE, __LINE__, __func__, buffer)

#define log_oom() log_oom_internal(LOG_ERR, PROJECT_FILE, __LINE__, __func__)
#define log_oom_debug() log_oom_internal(LOG_DEBUG, PROJECT_FILE, __LINE__, __func__)
#define log_oom_warning() log_oom_internal(LOG_WARNING, PROJECT_FILE, __LINE__, __func__)

bool log_on_console(void) _pure_;

/* Helper to wrap the main message in structured logging. The macro doesn't do much,
 * except to provide visual grouping of the format string and its arguments. */
#if LOG_MESSAGE_VERIFICATION || defined(__COVERITY__)
/* Do a fake formatting of the message string to let the scanner verify the arguments against the format
 * message. The variable will never be set to true, but we don't tell the compiler that :) */
extern bool _log_message_dummy;
#  define LOG_MESSAGE(fmt, ...) "MESSAGE=%.0d" fmt, (_log_message_dummy && printf(fmt, ##__VA_ARGS__)), ##__VA_ARGS__
#else
#  define LOG_MESSAGE(fmt, ...) "MESSAGE=" fmt, ##__VA_ARGS__
#endif

void log_received_signal(int level, const struct signalfd_siginfo *si);

/* If turned on, any requests for a log target involving "syslog" will be implicitly upgraded to the equivalent journal target */
void log_set_upgrade_syslog_to_journal(bool b);

/* If turned on, and log_open() is called, we'll not use STDERR_FILENO for logging ever, but rather open /dev/console */
void log_set_always_reopen_console(bool b);

/* If turned on, we'll open the log stream implicitly if needed on each individual log call. This is normally not
 * desired as we want to reuse our logging streams. It is useful however  */
void log_set_open_when_needed(bool b);

/* 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
 * stderr, the console or kmsg */
void log_set_prohibit_ipc(bool b);

void log_set_assert_return_is_critical(bool b);
bool log_get_assert_return_is_critical(void) _pure_;

int log_dup_console(void);

#if 0 /* NM_IGNORED */
int log_syntax_internal(
                const char *unit,
                int level,
                const char *config_file,
                unsigned config_line,
                int error,
                const char *file,
                int line,
                const char *func,
                const char *format, ...) _printf_(9, 10);
#else /* NM_IGNORED */
#define log_syntax_internal(unit, level, config_file, config_line, error, file, line, func, format, ...) \
    log_internal((level), (error), file, (line), (func), "syntax[%s]: "format, (config_file), __VA_ARGS__)
#endif /* NM_IGNORED */

int log_syntax_invalid_utf8_internal(
                const char *unit,
                int level,
                const char *config_file,
                unsigned config_line,
                const char *file,
                int line,
                const char *func,
                const char *rvalue);

#define log_syntax(unit, level, config_file, config_line, error, ...)   \
        ({                                                              \
                int _level = (level), _e = (error);                     \
                (log_get_max_level() >= LOG_PRI(_level))                \
                        ? log_syntax_internal(unit, _level, config_file, config_line, _e, PROJECT_FILE, __LINE__, __func__, __VA_ARGS__) \
                        : -ERRNO_VALUE(_e);                             \
        })

#define log_syntax_invalid_utf8(unit, level, config_file, config_line, rvalue) \
        ({                                                              \
                int _level = (level);                                   \
                (log_get_max_level() >= LOG_PRI(_level))                \
                        ? log_syntax_invalid_utf8_internal(unit, _level, config_file, config_line, PROJECT_FILE, __LINE__, __func__, rvalue) \
                        : -EINVAL;                                      \
        })

#define DEBUG_LOGGING _unlikely_(log_get_max_level() >= LOG_DEBUG)

void log_setup(void);

typedef struct LogRateLimit {
        int error;
        int level;
        RateLimit ratelimit;
} LogRateLimit;

#define log_ratelimit_internal(_level, _error, _ratelimit, _file, _line, _func, _format, ...)        \
({                                                                              \
        int _log_ratelimit_error = (_error);                                    \
        int _log_ratelimit_level = (_level);                                    \
        static LogRateLimit _log_ratelimit = {                                  \
                .ratelimit = (_ratelimit),                                      \
        };                                                                      \
        unsigned _num_dropped_errors = ratelimit_num_dropped(&_log_ratelimit.ratelimit); \
        if (_log_ratelimit_error != _log_ratelimit.error || _log_ratelimit_level != _log_ratelimit.level) { \
                ratelimit_reset(&_log_ratelimit.ratelimit);                     \
                _log_ratelimit.error = _log_ratelimit_error;                    \
                _log_ratelimit.level = _log_ratelimit_level;                    \
        }                                                                       \
        if (log_get_max_level() == LOG_DEBUG || ratelimit_below(&_log_ratelimit.ratelimit)) \
                _log_ratelimit_error = _num_dropped_errors > 0                  \
                ? log_internal(_log_ratelimit_level, _log_ratelimit_error, _file, _line, _func, _format " (Dropped %u similar message(s))", ##__VA_ARGS__, _num_dropped_errors) \
                : log_internal(_log_ratelimit_level, _log_ratelimit_error, _file, _line, _func, _format, ##__VA_ARGS__); \
        _log_ratelimit_error;                                                   \
})

#define log_ratelimit_full_errno(level, error, _ratelimit, format, ...)             \
        ({                                                              \
                int _level = (level), _e = (error);                     \
                _e = (log_get_max_level() >= LOG_PRI(_level))           \
                        ? log_ratelimit_internal(_level, _e, _ratelimit, PROJECT_FILE, __LINE__, __func__, format, ##__VA_ARGS__) \
                        : -ERRNO_VALUE(_e);                             \
                _e < 0 ? _e : -ESTRPIPE;                                \
        })

#define log_ratelimit_full(level, _ratelimit, format, ...)                          \
        log_ratelimit_full_errno(level, 0, _ratelimit, format, ##__VA_ARGS__)

/* Normal logging */
#define log_ratelimit_info(...)      log_ratelimit_full(LOG_INFO,    __VA_ARGS__)
#define log_ratelimit_notice(...)    log_ratelimit_full(LOG_NOTICE,  __VA_ARGS__)
#define log_ratelimit_warning(...)   log_ratelimit_full(LOG_WARNING, __VA_ARGS__)
#define log_ratelimit_error(...)     log_ratelimit_full(LOG_ERR,     __VA_ARGS__)
#define log_ratelimit_emergency(...) log_ratelimit_full(log_emergency_level(), __VA_ARGS__)

/* Logging triggered by an errno-like error */
#define log_ratelimit_info_errno(error, ...)      log_ratelimit_full_errno(LOG_INFO,    error, __VA_ARGS__)
#define log_ratelimit_notice_errno(error, ...)    log_ratelimit_full_errno(LOG_NOTICE,  error, __VA_ARGS__)
#define log_ratelimit_warning_errno(error, ...)   log_ratelimit_full_errno(LOG_WARNING, error, __VA_ARGS__)
#define log_ratelimit_error_errno(error, ...)     log_ratelimit_full_errno(LOG_ERR,     error, __VA_ARGS__)
#define log_ratelimit_emergency_errno(error, ...) log_ratelimit_full_errno(log_emergency_level(), error, __VA_ARGS__)

const char *_log_set_prefix(const char *prefix, bool force);
static inline const char *_log_unset_prefixp(const char **p) {
        assert(p);
        _log_set_prefix(*p, true);
        return NULL;
}

#define LOG_SET_PREFIX(prefix) \
        _cleanup_(_log_unset_prefixp) _unused_ const char *CONCATENATE(_cleanup_log_unset_prefix_, UNIQ) = _log_set_prefix(prefix, false);

/*
 * The log context allows attaching extra metadata to log messages written to the journal via log.h. We keep
 * track of a thread local log context onto which we can push extra metadata fields that should be logged.
 *
 * LOG_CONTEXT_PUSH() will add the provided field to the log context and will remove it again when the
 * current block ends. LOG_CONTEXT_PUSH_STRV() will do the same but for all fields in the given strv.
 * LOG_CONTEXT_PUSHF() is like LOG_CONTEXT_PUSH() but takes a format string and arguments.
 *
 * Using the macros is as simple as putting them anywhere inside a block to add a field to all following log
 * messages logged from inside that block.
 *
 * void myfunction(...) {
 *         ...
 *
 *         LOG_CONTEXT_PUSHF("MYMETADATA=%s", "abc");
 *
 *         // Every journal message logged will now have the MYMETADATA=abc
 *         // field included.
 * }
 *
 * One special case to note is async code, where we use callbacks that are invoked to continue processing
 * when some event occurs. For async code, there's usually an associated "userdata" struct containing all the
 * information associated with the async operation. In this "userdata" struct, we can store a log context
 * allocated with log_context_new() and freed with log_context_free(). We can then add and remove fields to
 * the `fields` member of the log context object and all those fields will be logged along with each log
 * message.
 */

typedef struct LogContext LogContext;

bool log_context_enabled(void);

LogContext* log_context_new(const char *key, const char *value);
LogContext* log_context_new_strv(char **fields, bool owned);
LogContext* log_context_new_iov(struct iovec *input_iovec, size_t n_input_iovec, bool owned);

/* Same as log_context_new(), but frees the given fields strv/iovec on failure. */
LogContext* log_context_new_strv_consume(char **fields);
LogContext* log_context_new_iov_consume(struct iovec *input_iovec, size_t n_input_iovec);

LogContext *log_context_ref(LogContext *c);
LogContext *log_context_unref(LogContext *c);

DEFINE_TRIVIAL_CLEANUP_FUNC(LogContext*, log_context_unref);

/* Returns the number of attached log context objects. */
size_t log_context_num_contexts(void);
/* Returns the number of fields in all attached log contexts. */
size_t log_context_num_fields(void);

#define LOG_CONTEXT_PUSH(...) \
        LOG_CONTEXT_PUSH_STRV(STRV_MAKE(__VA_ARGS__))

#define LOG_CONTEXT_PUSHF(...) \
        LOG_CONTEXT_PUSH(snprintf_ok((char[LINE_MAX]) {}, LINE_MAX, __VA_ARGS__))

#define _LOG_CONTEXT_PUSH_KEY_VALUE(key, value, c) \
        _unused_ _cleanup_(log_context_unrefp) LogContext *c = log_context_new(key, value);

#define LOG_CONTEXT_PUSH_KEY_VALUE(key, value) \
        _LOG_CONTEXT_PUSH_KEY_VALUE(key, value, UNIQ_T(c, UNIQ))

#define _LOG_CONTEXT_PUSH_STRV(strv, c) \
        _unused_ _cleanup_(log_context_unrefp) LogContext *c = log_context_new_strv(strv, /*owned=*/ false);

#define LOG_CONTEXT_PUSH_STRV(strv) \
        _LOG_CONTEXT_PUSH_STRV(strv, UNIQ_T(c, UNIQ))

#define _LOG_CONTEXT_PUSH_IOV(input_iovec, n_input_iovec, c) \
        _unused_ _cleanup_(log_context_unrefp) LogContext *c = log_context_new_iov(input_iovec, n_input_iovec, /*owned=*/ false);

#define LOG_CONTEXT_PUSH_IOV(input_iovec, n_input_iovec) \
        _LOG_CONTEXT_PUSH_IOV(input_iovec, n_input_iovec, UNIQ_T(c, UNIQ))

/* LOG_CONTEXT_CONSUME_STR()/LOG_CONTEXT_CONSUME_STRV()/LOG_CONTEXT_CONSUME_IOV() are identical to
 * LOG_CONTEXT_PUSH_STR()/LOG_CONTEXT_PUSH_STRV()/LOG_CONTEXT_PUSH_IOV() except they take ownership of the
 * given str/strv argument.
 */

#define _LOG_CONTEXT_CONSUME_STR(s, c, strv) \
        _unused_ _cleanup_strv_free_ strv = strv_new(s);                                                \
        if (!strv)                                                                                      \
                free(s);                                                                                \
        _unused_ _cleanup_(log_context_unrefp) LogContext *c = log_context_new_strv_consume(TAKE_PTR(strv))

#define LOG_CONTEXT_CONSUME_STR(s) \
        _LOG_CONTEXT_CONSUME_STR(s, UNIQ_T(c, UNIQ), UNIQ_T(sv, UNIQ))

#define _LOG_CONTEXT_CONSUME_STRV(strv, c) \
        _unused_ _cleanup_(log_context_unrefp) LogContext *c = log_context_new_strv_consume(strv);

#define LOG_CONTEXT_CONSUME_STRV(strv) \
        _LOG_CONTEXT_CONSUME_STRV(strv, UNIQ_T(c, UNIQ))

#define _LOG_CONTEXT_CONSUME_IOV(input_iovec, n_input_iovec, c) \
        _unused_ _cleanup_(log_context_unrefp) LogContext *c = log_context_new_iov_consume(input_iovec, n_input_iovec);

#define LOG_CONTEXT_CONSUME_IOV(input_iovec, n_input_iovec) \
        _LOG_CONTEXT_CONSUME_IOV(input_iovec, n_input_iovec, UNIQ_T(c, UNIQ))