1 /* GLIB - Library of useful routines for C programming
2 * Copyright (C) 1995-1997 Peter Mattis, Spencer Kimball and Josh MacDonald
4 * This library is free software; you can redistribute it and/or
5 * modify it under the terms of the GNU Lesser General Public
6 * License as published by the Free Software Foundation; either
7 * version 2.1 of the License, or (at your option) any later version.
9 * This library is distributed in the hope that it will be useful,
10 * but WITHOUT ANY WARRANTY; without even the implied warranty of
11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
12 * Lesser General Public License for more details.
14 * You should have received a copy of the GNU Lesser General Public
15 * License along with this library; if not, see <http://www.gnu.org/licenses/>.
19 * Modified by the GLib Team and others 1997-2000. See the AUTHORS
20 * file for a list of people on the GLib Team. See the ChangeLog
21 * files for a list of changes. These files are distributed with
22 * GLib at ftp://ftp.gtk.org/pub/gtk/.
25 #ifndef __G_MESSAGES_H__
26 #define __G_MESSAGES_H__
28 #if !defined (__GLIB_H_INSIDE__) && !defined (GLIB_COMPILATION)
29 #error "Only <glib.h> can be included directly."
33 #include <glib/gatomic.h>
34 #include <glib/gtypes.h>
35 #include <glib/gmacros.h>
36 #include <glib/gvariant.h>
40 /* calculate a string size, guaranteed to fit format + args.
43 gsize g_printf_string_upper_bound (const gchar* format,
44 va_list args) G_GNUC_PRINTF(1, 0);
46 /* Log level shift offset for user defined
47 * log levels (0-7 are used by GLib).
49 #define G_LOG_LEVEL_USER_SHIFT (8)
51 /* Glib log levels and flags.
56 G_LOG_FLAG_RECURSION = 1 << 0,
57 G_LOG_FLAG_FATAL = 1 << 1,
60 G_LOG_LEVEL_ERROR = 1 << 2, /* always fatal */
61 G_LOG_LEVEL_CRITICAL = 1 << 3,
62 G_LOG_LEVEL_WARNING = 1 << 4,
63 G_LOG_LEVEL_MESSAGE = 1 << 5,
64 G_LOG_LEVEL_INFO = 1 << 6,
65 G_LOG_LEVEL_DEBUG = 1 << 7,
67 G_LOG_LEVEL_MASK = ~(G_LOG_FLAG_RECURSION | G_LOG_FLAG_FATAL)
70 /* GLib log levels that are considered fatal by default */
71 #define G_LOG_FATAL_MASK (G_LOG_FLAG_RECURSION | G_LOG_LEVEL_ERROR)
73 typedef void (*GLogFunc) (const gchar *log_domain,
74 GLogLevelFlags log_level,
81 guint g_log_set_handler (const gchar *log_domain,
82 GLogLevelFlags log_levels,
85 GLIB_AVAILABLE_IN_2_46
86 guint g_log_set_handler_full (const gchar *log_domain,
87 GLogLevelFlags log_levels,
90 GDestroyNotify destroy);
92 void g_log_remove_handler (const gchar *log_domain,
95 void g_log_default_handler (const gchar *log_domain,
96 GLogLevelFlags log_level,
98 gpointer unused_data);
100 GLogFunc g_log_set_default_handler (GLogFunc log_func,
102 GLIB_AVAILABLE_IN_ALL
103 void g_log (const gchar *log_domain,
104 GLogLevelFlags log_level,
106 ...) G_GNUC_PRINTF (3, 4);
107 GLIB_AVAILABLE_IN_ALL
108 void g_logv (const gchar *log_domain,
109 GLogLevelFlags log_level,
111 va_list args) G_GNUC_PRINTF(3, 0);
112 GLIB_AVAILABLE_IN_ALL
113 GLogLevelFlags g_log_set_fatal_mask (const gchar *log_domain,
114 GLogLevelFlags fatal_mask);
115 GLIB_AVAILABLE_IN_ALL
116 GLogLevelFlags g_log_set_always_fatal (GLogLevelFlags fatal_mask);
118 /* Structured logging mechanism. */
122 * @G_LOG_WRITER_HANDLED: Log writer has handled the log entry.
123 * @G_LOG_WRITER_UNHANDLED: Log writer could not handle the log entry.
125 * Return values from #GLogWriterFuncs to indicate whether the given log entry
126 * was successfully handled by the writer, or whether there was an error in
127 * handling it (and hence a fallback writer should be used).
129 * If a #GLogWriterFunc ignores a log entry, it should return
130 * %G_LOG_WRITER_HANDLED.
136 G_LOG_WRITER_HANDLED = 1,
137 G_LOG_WRITER_UNHANDLED = 0,
142 * @key: field name (UTF-8 string)
143 * @value: field value (arbitrary bytes)
144 * @length: length of @value, in bytes, or -1 if it is nul-terminated
146 * Structure representing a single field in a structured log entry. See
147 * g_log_structured() for details.
149 * Log fields may contain arbitrary values, including binary with embedded nul
150 * bytes. If the field contains a string, the string must be UTF-8 encoded and
151 * have a trailing nul byte. Otherwise, @length must be set to a non-negative
156 typedef struct _GLogField GLogField;
166 * @log_level: log level of the message
167 * @fields: (array length=n_fields): fields forming the message
168 * @n_fields: number of @fields
169 * @user_data: user data passed to g_log_set_writer_func()
171 * Writer function for log entries. A log entry is a collection of one or more
172 * #GLogFields, using the standard [field names from journal
173 * specification](https://www.freedesktop.org/software/systemd/man/systemd.journal-fields.html).
174 * See g_log_structured() for more information.
176 * Writer functions must ignore fields which they do not recognise, unless they
177 * can write arbitrary binary output, as field values may be arbitrary binary.
179 * @log_level is guaranteed to be included in @fields as the `PRIORITY` field,
180 * but is provided separately for convenience of deciding whether or where to
181 * output the log entry.
183 * Writer functions should return %G_LOG_WRITER_HANDLED if they handled the log
184 * message successfully or if they deliberately ignored it. If there was an
185 * error handling the message (for example, if the writer function is meant to
186 * send messages to a remote logging server and there is a network error), it
187 * should return %G_LOG_WRITER_UNHANDLED. This allows writer functions to be
188 * chained and fall back to simpler handlers in case of failure.
190 * Returns: %G_LOG_WRITER_HANDLED if the log entry was handled successfully;
191 * %G_LOG_WRITER_UNHANDLED otherwise
194 typedef GLogWriterOutput (*GLogWriterFunc) (GLogLevelFlags log_level,
195 const GLogField *fields,
199 GLIB_AVAILABLE_IN_2_50
200 void g_log_structured (const gchar *log_domain,
201 GLogLevelFlags log_level,
203 GLIB_AVAILABLE_IN_2_50
204 void g_log_structured_array (GLogLevelFlags log_level,
205 const GLogField *fields,
208 GLIB_AVAILABLE_IN_2_50
209 void g_log_variant (const gchar *log_domain,
210 GLogLevelFlags log_level,
213 GLIB_AVAILABLE_IN_2_50
214 void g_log_set_writer_func (GLogWriterFunc func,
216 GDestroyNotify user_data_free);
218 GLIB_AVAILABLE_IN_2_50
219 gboolean g_log_writer_supports_color (gint output_fd);
220 GLIB_AVAILABLE_IN_2_50
221 gboolean g_log_writer_is_journald (gint output_fd);
223 GLIB_AVAILABLE_IN_2_50
224 gchar *g_log_writer_format_fields (GLogLevelFlags log_level,
225 const GLogField *fields,
229 GLIB_AVAILABLE_IN_2_50
230 GLogWriterOutput g_log_writer_journald (GLogLevelFlags log_level,
231 const GLogField *fields,
234 GLIB_AVAILABLE_IN_2_50
235 GLogWriterOutput g_log_writer_standard_streams (GLogLevelFlags log_level,
236 const GLogField *fields,
239 GLIB_AVAILABLE_IN_2_50
240 GLogWriterOutput g_log_writer_default (GLogLevelFlags log_level,
241 const GLogField *fields,
248 * A convenience form of g_log_structured(), recommended to be added to
249 * functions when debugging. It prints the current monotonic time and the code
250 * location using %G_STRLOC.
254 #define G_DEBUG_HERE() \
255 g_log_structured (G_LOG_DOMAIN, G_LOG_LEVEL_DEBUG, \
256 "CODE_FILE", __FILE__, \
257 "CODE_LINE", G_STRINGIFY (__LINE__), \
258 "CODE_FUNC", G_STRFUNC, \
259 "MESSAGE", "%" G_GINT64_FORMAT ": %s", \
260 g_get_monotonic_time (), G_STRLOC)
263 void _g_log_fallback_handler (const gchar *log_domain,
264 GLogLevelFlags log_level,
265 const gchar *message,
266 gpointer unused_data);
268 /* Internal functions, used to implement the following macros */
269 GLIB_AVAILABLE_IN_ALL
270 void g_return_if_fail_warning (const char *log_domain,
271 const char *pretty_function,
272 const char *expression) G_ANALYZER_NORETURN;
273 GLIB_AVAILABLE_IN_ALL
274 void g_warn_message (const char *domain,
278 const char *warnexpr) G_ANALYZER_NORETURN;
280 void g_assert_warning (const char *log_domain,
283 const char *pretty_function,
284 const char *expression) G_GNUC_NORETURN;
286 GLIB_AVAILABLE_IN_2_56
287 void g_log_structured_standard (const gchar *log_domain,
288 GLogLevelFlags log_level,
292 const gchar *message_format,
293 ...) G_GNUC_PRINTF (6, 7);
296 #define G_LOG_DOMAIN ((gchar*) 0)
297 #endif /* G_LOG_DOMAIN */
299 #if defined(G_HAVE_ISO_VARARGS) && !G_ANALYZER_ANALYZING
300 #if defined(G_LOG_USE_STRUCTURED) && GLIB_VERSION_MAX_ALLOWED >= GLIB_VERSION_2_56
301 #define g_error(...) G_STMT_START { \
302 g_log_structured_standard (G_LOG_DOMAIN, G_LOG_LEVEL_ERROR, \
303 __FILE__, G_STRINGIFY (__LINE__), \
304 G_STRFUNC, __VA_ARGS__); \
307 #define g_message(...) g_log_structured_standard (G_LOG_DOMAIN, G_LOG_LEVEL_MESSAGE, \
308 __FILE__, G_STRINGIFY (__LINE__), \
309 G_STRFUNC, __VA_ARGS__)
310 #define g_critical(...) g_log_structured_standard (G_LOG_DOMAIN, G_LOG_LEVEL_CRITICAL, \
311 __FILE__, G_STRINGIFY (__LINE__), \
312 G_STRFUNC, __VA_ARGS__)
313 #define g_warning(...) g_log_structured_standard (G_LOG_DOMAIN, G_LOG_LEVEL_WARNING, \
314 __FILE__, G_STRINGIFY (__LINE__), \
315 G_STRFUNC, __VA_ARGS__)
316 #define g_info(...) g_log_structured_standard (G_LOG_DOMAIN, G_LOG_LEVEL_INFO, \
317 __FILE__, G_STRINGIFY (__LINE__), \
318 G_STRFUNC, __VA_ARGS__)
319 #define g_debug(...) g_log_structured_standard (G_LOG_DOMAIN, G_LOG_LEVEL_DEBUG, \
320 __FILE__, G_STRINGIFY (__LINE__), \
321 G_STRFUNC, __VA_ARGS__)
323 /* for(;;) ; so that GCC knows that control doesn't go past g_error().
324 * Put space before ending semicolon to avoid C++ build warnings.
326 #define g_error(...) G_STMT_START { \
327 g_log (G_LOG_DOMAIN, \
332 #define g_message(...) g_log (G_LOG_DOMAIN, \
333 G_LOG_LEVEL_MESSAGE, \
335 #define g_critical(...) g_log (G_LOG_DOMAIN, \
336 G_LOG_LEVEL_CRITICAL, \
338 #define g_warning(...) g_log (G_LOG_DOMAIN, \
339 G_LOG_LEVEL_WARNING, \
341 #define g_info(...) g_log (G_LOG_DOMAIN, \
344 #define g_debug(...) g_log (G_LOG_DOMAIN, \
348 #elif defined(G_HAVE_GNUC_VARARGS) && !G_ANALYZER_ANALYZING
349 #if defined(G_LOG_USE_STRUCTURED) && GLIB_VERSION_MAX_ALLOWED >= GLIB_VERSION_2_56
350 #define g_error(format...) G_STMT_START { \
351 g_log_structured_standard (G_LOG_DOMAIN, G_LOG_LEVEL_ERROR, \
352 __FILE__, G_STRINGIFY (__LINE__), \
353 G_STRFUNC, format); \
356 #define g_message(format...) g_log_structured_standard (G_LOG_DOMAIN, G_LOG_LEVEL_MESSAGE, \
357 __FILE__, G_STRINGIFY (__LINE__), \
359 #define g_critical(format...) g_log_structured_standard (G_LOG_DOMAIN, G_LOG_LEVEL_CRITICAL, \
360 __FILE__, G_STRINGIFY (__LINE__), \
362 #define g_warning(format...) g_log_structured_standard (G_LOG_DOMAIN, G_LOG_LEVEL_WARNING, \
363 __FILE__, G_STRINGIFY (__LINE__), \
365 #define g_info(format...) g_log_structured_standard (G_LOG_DOMAIN, G_LOG_LEVEL_INFO, \
366 __FILE__, G_STRINGIFY (__LINE__), \
368 #define g_debug(format...) g_log_structured_standard (G_LOG_DOMAIN, G_LOG_LEVEL_DEBUG, \
369 __FILE__, G_STRINGIFY (__LINE__), \
372 #define g_error(format...) G_STMT_START { \
373 g_log (G_LOG_DOMAIN, \
379 #define g_message(format...) g_log (G_LOG_DOMAIN, \
380 G_LOG_LEVEL_MESSAGE, \
382 #define g_critical(format...) g_log (G_LOG_DOMAIN, \
383 G_LOG_LEVEL_CRITICAL, \
385 #define g_warning(format...) g_log (G_LOG_DOMAIN, \
386 G_LOG_LEVEL_WARNING, \
388 #define g_info(format...) g_log (G_LOG_DOMAIN, \
391 #define g_debug(format...) g_log (G_LOG_DOMAIN, \
395 #else /* no varargs macros */
396 static void g_error (const gchar *format, ...) G_GNUC_NORETURN G_ANALYZER_NORETURN;
397 static void g_critical (const gchar *format, ...) G_ANALYZER_NORETURN;
400 g_error (const gchar *format,
404 va_start (args, format);
405 g_logv (G_LOG_DOMAIN, G_LOG_LEVEL_ERROR, format, args);
411 g_message (const gchar *format,
415 va_start (args, format);
416 g_logv (G_LOG_DOMAIN, G_LOG_LEVEL_MESSAGE, format, args);
420 g_critical (const gchar *format,
424 va_start (args, format);
425 g_logv (G_LOG_DOMAIN, G_LOG_LEVEL_CRITICAL, format, args);
429 g_warning (const gchar *format,
433 va_start (args, format);
434 g_logv (G_LOG_DOMAIN, G_LOG_LEVEL_WARNING, format, args);
438 g_info (const gchar *format,
442 va_start (args, format);
443 g_logv (G_LOG_DOMAIN, G_LOG_LEVEL_INFO, format, args);
447 g_debug (const gchar *format,
451 va_start (args, format);
452 g_logv (G_LOG_DOMAIN, G_LOG_LEVEL_DEBUG, format, args);
455 #endif /* !__GNUC__ */
459 * @...: format string, followed by parameters to insert
460 * into the format string (as with printf())
462 * Logs a warning only once.
464 * g_warning_once() calls g_warning() with the passed message the first time
465 * the statement is executed; subsequent times it is a no-op.
467 * Note! On platforms where the compiler doesn't support variadic macros, the
468 * warning is printed each time instead of only once.
472 #if defined(G_HAVE_ISO_VARARGS) && !G_ANALYZER_ANALYZING
473 #define g_warning_once(...) \
475 static volatile int G_PASTE (_GWarningOnceBoolean, __LINE__) = 0; \
476 if (g_atomic_int_compare_and_exchange (&G_PASTE (_GWarningOnceBoolean, __LINE__), \
478 g_warning (__VA_ARGS__); \
480 GLIB_AVAILABLE_MACRO_IN_2_64
481 #elif defined(G_HAVE_GNUC_VARARGS) && !G_ANALYZER_ANALYZING
482 #define g_warning_once(format...) \
484 static volatile int G_PASTE (_GWarningOnceBoolean, __LINE__) = 0; \
485 if (g_atomic_int_compare_and_exchange (&G_PASTE (_GWarningOnceBoolean, __LINE__), \
487 g_warning (format); \
489 GLIB_AVAILABLE_MACRO_IN_2_64
491 #define g_warning_once g_warning
496 * @string: the message to output
498 * Specifies the type of the print handler functions.
499 * These are called with the complete formatted string to output.
501 typedef void (*GPrintFunc) (const gchar *string);
502 GLIB_AVAILABLE_IN_ALL
503 void g_print (const gchar *format,
504 ...) G_GNUC_PRINTF (1, 2);
505 GLIB_AVAILABLE_IN_ALL
506 GPrintFunc g_set_print_handler (GPrintFunc func);
507 GLIB_AVAILABLE_IN_ALL
508 void g_printerr (const gchar *format,
509 ...) G_GNUC_PRINTF (1, 2);
510 GLIB_AVAILABLE_IN_ALL
511 GPrintFunc g_set_printerr_handler (GPrintFunc func);
520 #define g_warn_if_reached() \
522 g_warn_message (G_LOG_DOMAIN, __FILE__, __LINE__, G_STRFUNC, NULL); \
527 * @expr: the expression to check
529 * Logs a warning if the expression is not true.
533 #define g_warn_if_fail(expr) \
535 if G_LIKELY (expr) ; \
536 else g_warn_message (G_LOG_DOMAIN, __FILE__, __LINE__, G_STRFUNC, #expr); \
539 #ifdef G_DISABLE_CHECKS
543 * @expr: the expression to check
545 * Verifies that the expression @expr, usually representing a precondition,
546 * evaluates to %TRUE. If the function returns a value, use
547 * g_return_val_if_fail() instead.
549 * If @expr evaluates to %FALSE, the current function should be considered to
550 * have undefined behaviour (a programmer error). The only correct solution
551 * to such an error is to change the module that is calling the current
552 * function, so that it avoids this incorrect call.
554 * To make this undefined behaviour visible, if @expr evaluates to %FALSE,
555 * the result is usually that a critical message is logged and the current
558 * If `G_DISABLE_CHECKS` is defined then the check is not performed. You
559 * should therefore not depend on any side effects of @expr.
561 * To debug failure of a g_return_if_fail() check, run the code under a debugger
562 * with `G_DEBUG=fatal-criticals` or `G_DEBUG=fatal-warnings` defined in the
563 * environment (see [Running GLib Applications](glib-running.html)):
566 * G_DEBUG=fatal-warnings gdb ./my-program
569 * Any unrelated failures can be skipped over in
570 * [gdb](https://www.gnu.org/software/gdb/) using the `continue` command.
572 #define g_return_if_fail(expr) G_STMT_START{ (void)0; }G_STMT_END
575 * g_return_val_if_fail:
576 * @expr: the expression to check
577 * @val: the value to return from the current function
578 * if the expression is not true
580 * Verifies that the expression @expr, usually representing a precondition,
581 * evaluates to %TRUE. If the function does not return a value, use
582 * g_return_if_fail() instead.
584 * If @expr evaluates to %FALSE, the current function should be considered to
585 * have undefined behaviour (a programmer error). The only correct solution
586 * to such an error is to change the module that is calling the current
587 * function, so that it avoids this incorrect call.
589 * To make this undefined behaviour visible, if @expr evaluates to %FALSE,
590 * the result is usually that a critical message is logged and @val is
591 * returned from the current function.
593 * If `G_DISABLE_CHECKS` is defined then the check is not performed. You
594 * should therefore not depend on any side effects of @expr.
596 * See g_return_if_fail() for guidance on how to debug failure of this check.
598 #define g_return_val_if_fail(expr,val) G_STMT_START{ (void)0; }G_STMT_END
601 * g_return_if_reached:
603 * Logs a critical message and returns from the current function.
604 * This can only be used in functions which do not return a value.
606 * See g_return_if_fail() for guidance on how to debug failure of this check.
608 #define g_return_if_reached() G_STMT_START{ return; }G_STMT_END
611 * g_return_val_if_reached:
612 * @val: the value to return from the current function
614 * Logs a critical message and returns @val.
616 * See g_return_if_fail() for guidance on how to debug failure of this check.
618 #define g_return_val_if_reached(val) G_STMT_START{ return (val); }G_STMT_END
620 #else /* !G_DISABLE_CHECKS */
622 #define g_return_if_fail(expr) \
624 if (G_LIKELY (expr)) \
628 g_return_if_fail_warning (G_LOG_DOMAIN, \
635 #define g_return_val_if_fail(expr, val) \
637 if (G_LIKELY (expr)) \
641 g_return_if_fail_warning (G_LOG_DOMAIN, \
648 #define g_return_if_reached() \
650 g_log (G_LOG_DOMAIN, \
651 G_LOG_LEVEL_CRITICAL, \
652 "file %s: line %d (%s): should not be reached", \
659 #define g_return_val_if_reached(val) \
661 g_log (G_LOG_DOMAIN, \
662 G_LOG_LEVEL_CRITICAL, \
663 "file %s: line %d (%s): should not be reached", \
670 #endif /* !G_DISABLE_CHECKS */
674 #endif /* __G_MESSAGES_H__ */