2 * Copyright (C) 2004 Internet Systems Consortium, Inc. ("ISC")
3 * Copyright (C) 1999-2003 Internet Software Consortium.
5 * Permission to use, copy, modify, and distribute this software for any
6 * purpose with or without fee is hereby granted, provided that the above
7 * copyright notice and this permission notice appear in all copies.
9 * THE SOFTWARE IS PROVIDED "AS IS" AND ISC DISCLAIMS ALL WARRANTIES WITH
10 * REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY
11 * AND FITNESS. IN NO EVENT SHALL ISC BE LIABLE FOR ANY SPECIAL, DIRECT,
12 * INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM
13 * LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE
14 * OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR
15 * PERFORMANCE OF THIS SOFTWARE.
18 /* $Id: log.h,v 1.39.2.6 2004/04/10 04:30:06 marka Exp $ */
25 #include <syslog.h> /* XXXDCL NT */
27 #include <isc/formatcheck.h>
29 #include <isc/platform.h>
30 #include <isc/types.h>
33 * Severity levels, patterned after Unix's syslog levels.
35 * ISC_LOG_DYNAMIC can only be used for defining channels with
36 * isc_log_createchannel(), not to specify a level in isc_log_write().
38 #define ISC_LOG_DEBUG(level) (level)
39 #define ISC_LOG_DYNAMIC 0
40 #define ISC_LOG_INFO (-1)
41 #define ISC_LOG_NOTICE (-2)
42 #define ISC_LOG_WARNING (-3)
43 #define ISC_LOG_ERROR (-4)
44 #define ISC_LOG_CRITICAL (-5)
49 #define ISC_LOG_TONULL 1
50 #define ISC_LOG_TOSYSLOG 2
51 #define ISC_LOG_TOFILE 3
52 #define ISC_LOG_TOFILEDESC 4
57 #define ISC_LOG_PRINTTIME 0x0001
58 #define ISC_LOG_PRINTLEVEL 0x0002
59 #define ISC_LOG_PRINTCATEGORY 0x0004
60 #define ISC_LOG_PRINTMODULE 0x0008
61 #define ISC_LOG_PRINTTAG 0x0010
62 #define ISC_LOG_PRINTALL 0x001F
63 #define ISC_LOG_DEBUGONLY 0x1000
64 #define ISC_LOG_OPENERR 0x8000 /* internal */
68 * XXXDCL INFINITE doesn't yet work. Arguably it isn't needed, but
69 * since I am intend to make large number of versions work efficiently,
70 * INFINITE is going to be trivial to add to that.
72 #define ISC_LOG_ROLLINFINITE (-1)
73 #define ISC_LOG_ROLLNEVER (-2)
76 * Used to name the categories used by a library. An array of isc_logcategory
77 * structures names each category, and the id value is initialized by calling
78 * isc_log_registercategories.
80 struct isc_logcategory {
86 * Similar to isc_logcategory above, but for all the modules a library defines.
88 struct isc_logmodule {
94 * The isc_logfile structure is initialized as part of an isc_logdestination
95 * before calling isc_log_createchannel(). When defining an ISC_LOG_TOFILE
96 * channel the name, versions and maximum_size should be set before calling
97 * isc_log_createchannel(). To define an ISC_LOG_TOFILEDESC channel set only
98 * the stream before the call.
100 * Setting maximum_size to zero implies no maximum.
102 typedef struct isc_logfile {
103 FILE *stream; /* Initialized to NULL for ISC_LOG_TOFILE. */
104 const char *name; /* NULL for ISC_LOG_TOFILEDESC. */
105 int versions; /* >= 0, ISC_LOG_ROLLNEVER, ISC_LOG_ROLLINFINITE. */
107 * stdio's ftell is standardized to return a long, which may well not
108 * be big enough for the largest file supportable by the operating
109 * system (though it is _probably_ big enough for the largest log
110 * anyone would want). st_size returned by fstat should be typedef'd
111 * to a size large enough for the largest possible file on a system.
113 isc_offset_t maximum_size;
114 isc_boolean_t maximum_reached; /* Private. */
118 * Passed to isc_log_createchannel to define the attributes of either
119 * a stdio or a syslog log.
121 typedef union isc_logdestination {
123 int facility; /* XXXDCL NT */
124 } isc_logdestination_t;
127 * The built-in categories of libisc.
129 * Each library registering categories should provide library_LOGCATEGORY_name
130 * definitions with indexes into its isc_logcategory structure corresponding to
131 * the order of the names.
133 LIBISC_EXTERNAL_DATA extern isc_logcategory_t isc_categories[];
134 LIBISC_EXTERNAL_DATA extern isc_log_t *isc_lctx;
135 LIBISC_EXTERNAL_DATA extern isc_logmodule_t isc_modules[];
138 * Do not log directly to DEFAULT. Use another category. When in doubt,
141 #define ISC_LOGCATEGORY_DEFAULT (&isc_categories[0])
142 #define ISC_LOGCATEGORY_GENERAL (&isc_categories[1])
144 #define ISC_LOGMODULE_SOCKET (&isc_modules[0])
145 #define ISC_LOGMODULE_TIME (&isc_modules[1])
150 isc_log_create(isc_mem_t *mctx, isc_log_t **lctxp, isc_logconfig_t **lcfgp);
152 * Establish a new logging context, with default channels.
155 * isc_log_create calls isc_logconfig_create, so see its comment
156 * below for more information.
159 * mctx is a valid memory context.
160 * lctxp is not null and *lctxp is null.
161 * lcfgp is null or lcfgp is not null and *lcfgp is null.
164 * *lctxp will point to a valid logging context if all of the necessary
165 * memory was allocated, or NULL otherwise.
166 * *lcfgp will point to a valid logging configuration if all of the
167 * necessary memory was allocated, or NULL otherwise.
168 * On failure, no additional memory is allocated.
171 * ISC_R_SUCCESS Success
172 * ISC_R_NOMEMORY Resource limit: Out of memory
176 isc_logconfig_create(isc_log_t *lctx, isc_logconfig_t **lcfgp);
178 * Create the data structure that holds all of the configurable information
179 * about where messages are actually supposed to be sent -- the information
180 * that could changed based on some configuration file, as opposed to the
181 * the category/module specification of isc_log_[v]write[1] that is compiled
182 * into a program, or the debug_level which is dynamic state information.
185 * It is necessary to specify the logging context the configuration
186 * will be used with because the number of categories and modules
187 * needs to be known in order to set the configuration. However,
188 * the configuration is not used by the logging context until the
189 * isc_logconfig_use function is called.
191 * The memory context used for operations that allocate memory for
192 * the configuration is that of the logging context, as specified
193 * in the isc_log_create call.
195 * Four default channels are established:
197 * - log to syslog's daemon facility ISC_LOG_INFO or higher
199 * - log to stderr ISC_LOG_INFO or higher
201 * - log to stderr ISC_LOG_DEBUG dynamically
206 * lctx is a valid logging context.
207 * lcftp is not null and *lcfgp is null.
210 * *lcfgp will point to a valid logging context if all of the necessary
211 * memory was allocated, or NULL otherwise.
212 * On failure, no additional memory is allocated.
215 * ISC_R_SUCCESS Success
216 * ISC_R_NOMEMORY Resource limit: Out of memory
220 isc_logconfig_get(isc_log_t *lctx);
222 * Returns a pointer to the configuration currently in use by the log context.
225 * lctx is a valid context.
228 * The configuration pointer is non-null.
231 * The configuration pointer.
235 isc_logconfig_use(isc_log_t *lctx, isc_logconfig_t *lcfg);
237 * Associate a new configuration with a logging context.
240 * This is thread safe. The logging context will lock a mutex
241 * before attempting to swap in the new configuration, and isc_log_doit
242 * (the internal function used by all of isc_log_[v]write[1]) locks
243 * the same lock for the duration of its use of the configuration.
246 * lctx is a valid logging context.
247 * lcfg is a valid logging configuration.
248 * lctx is the same configuration given to isc_logconfig_create
249 * when the configuration was created.
252 * Future calls to isc_log_write will use the new configuration.
255 * ISC_R_SUCCESS Success
256 * ISC_R_NOMEMORY Resource limit: Out of memory
260 isc_log_destroy(isc_log_t **lctxp);
262 * Deallocate the memory associated with a logging context.
265 * *lctx is a valid logging context.
268 * All of the memory associated with the logging context is returned
269 * to the free memory pool.
271 * Any open files are closed.
273 * The logging context is marked as invalid.
277 isc_logconfig_destroy(isc_logconfig_t **lcfgp);
279 * Destroy a logging configuration.
282 * This function cannot be used directly with the return value of
283 * isc_logconfig_get, because a logging context must always have
284 * a valid configuration associated with it.
287 * lcfgp is not null and *lcfgp is a valid logging configuration.
288 * The logging configuration is not in use by an existing logging context.
291 * All memory allocated for the configuration is freed.
293 * The configuration is marked as invalid.
297 isc_log_registercategories(isc_log_t *lctx, isc_logcategory_t categories[]);
299 * Identify logging categories a library will use.
302 * A category should only be registered once, but no mechanism enforces
305 * The end of the categories array is identified by a NULL name.
307 * Because the name is used by ISC_LOG_PRINTCATEGORY, it should not
308 * be altered or destroyed after isc_log_registercategories().
310 * Because each element of the categories array is used by
311 * isc_log_categorybyname, it should not be altered or destroyed
312 * after registration.
314 * The value of the id integer in each structure is overwritten
315 * by this function, and so id need not be initialized to any particular
316 * value prior to the function call.
318 * A subsequent call to isc_log_registercategories with the same
319 * logging context (but new categories) will cause the last
320 * element of the categories array from the prior call to have
321 * its "name" member changed from NULL to point to the new
322 * categories array, and its "id" member set to UINT_MAX.
325 * lctx is a valid logging context.
326 * categories != NULL.
327 * categories[0].name != NULL.
330 * There are references to each category in the logging context,
331 * so they can be used with isc_log_usechannel() and isc_log_write().
335 isc_log_registermodules(isc_log_t *lctx, isc_logmodule_t modules[]);
337 * Identify logging categories a library will use.
340 * A module should only be registered once, but no mechanism enforces
343 * The end of the modules array is identified by a NULL name.
345 * Because the name is used by ISC_LOG_PRINTMODULE, it should not
346 * be altered or destroyed after isc_log_registermodules().
348 * Because each element of the modules array is used by
349 * isc_log_modulebyname, it should not be altered or destroyed
350 * after registration.
352 * The value of the id integer in each structure is overwritten
353 * by this function, and so id need not be initialized to any particular
354 * value prior to the function call.
356 * A subsequent call to isc_log_registermodules with the same
357 * logging context (but new modules) will cause the last
358 * element of the modules array from the prior call to have
359 * its "name" member changed from NULL to point to the new
360 * modules array, and its "id" member set to UINT_MAX.
363 * lctx is a valid logging context.
365 * modules[0].name != NULL;
368 * Each module has a reference in the logging context, so they can be
369 * used with isc_log_usechannel() and isc_log_write().
373 isc_log_createchannel(isc_logconfig_t *lcfg, const char *name,
374 unsigned int type, int level,
375 const isc_logdestination_t *destination,
378 * Specify the parameters of a logging channel.
381 * The name argument is copied to memory in the logging context, so
382 * it can be altered or destroyed after isc_log_createchannel().
384 * Defining a very large number of channels will have a performance
385 * impact on isc_log_usechannel(), since the names are searched
386 * linearly until a match is made. This same issue does not affect
387 * isc_log_write, however.
389 * Channel names can be redefined; this is primarily useful for programs
390 * that want their own definition of default_syslog, default_debug
391 * and default_stderr.
393 * Any channel that is redefined will not affect logging that was
394 * already directed to its original definition, _except_ for the
395 * default_stderr channel. This case is handled specially so that
396 * the default logging category can be changed by redefining
397 * default_stderr. (XXXDCL Though now that I think of it, the default
398 * logging category can be changed with only one additional function
399 * call by defining a new channel and then calling isc_log_usechannel()
400 * for ISC_LOGCATEGORY_DEFAULT.)
402 * Specifying ISC_LOG_PRINTTIME or ISC_LOG_PRINTTAG for syslog is allowed,
403 * but probably not what you wanted to do.
405 * ISC_LOG_DEBUGONLY will mark the channel as usable only when the
406 * debug level of the logging context (see isc_log_setdebuglevel)
410 * lcfg is a valid logging configuration.
414 * type is ISC_LOG_TOSYSLOG, ISC_LOG_TOFILE, ISC_LOG_TOFILEDESC or
417 * destination is not NULL unless type is ISC_LOG_TONULL.
419 * level is >= ISC_LOG_CRITICAL (the most negative logging level).
421 * flags does not include any bits aside from the ISC_LOG_PRINT* bits
422 * or ISC_LOG_DEBUGONLY.
426 * A channel with the given name is usable with
427 * isc_log_usechannel().
429 * ISC_R_NOMEMORY or ISC_R_UNEXPECTED
430 * No additional memory is being used by the logging context.
432 * Any channel that previously existed with the given name
436 * ISC_R_SUCCESS Success
437 * ISC_R_NOMEMORY Resource limit: Out of memory
438 * ISC_R_UNEXPECTED type was out of range and REQUIRE()
443 isc_log_usechannel(isc_logconfig_t *lcfg, const char *name,
444 const isc_logcategory_t *category,
445 const isc_logmodule_t *module);
447 * Associate a named logging channel with a category and module that
451 * The name is searched for linearly in the set of known channel names
452 * until a match is found. (Note the performance impact of a very large
453 * number of named channels.) When multiple channels of the same
454 * name are defined, the most recent definition is found.
456 * Specifing a very large number of channels for a category will have
457 * a moderate impact on performance in isc_log_write(), as each
458 * call looks up the category for the start of a linked list, which
459 * it follows all the way to the end to find matching modules. The
460 * test for matching modules is integral, though.
462 * If category is NULL, then the channel is associated with the indicated
463 * module for all known categories (including the "default" category).
465 * If module is NULL, then the channel is associated with every module
466 * that uses that category.
468 * Passing both category and module as NULL would make every log message
469 * use the indicated channel.
471 * Specifying a channel that is ISC_LOG_TONULL for a category/module pair
472 * has no effect on any other channels associated with that pair,
473 * regardless of ordering. Thus you cannot use it to "mask out" one
474 * category/module pair when you have specified some other channel that
475 * is also used by that category/module pair.
478 * lcfg is a valid logging configuration.
480 * category is NULL or has an id that is in the range of known ids.
482 * module is NULL or has an id that is in the range of known ids.
486 * The channel will be used by the indicated category/module
490 * If assignment for a specific category has been requested,
491 * the channel has not been associated with the indicated
492 * category/module arguments and no additional memory is
493 * used by the logging context.
495 * If assignment for all categories has been requested
496 * then _some_ may have succeeded (starting with category
497 * "default" and progressing through the order of categories
498 * passed to isc_log_registercategories) and additional memory
499 * is being used by whatever assignments succeeded.
502 * ISC_R_SUCCESS Success
503 * ISC_R_NOMEMORY Resource limit: Out of memory
507 isc_log_write(isc_log_t *lctx, isc_logcategory_t *category,
508 isc_logmodule_t *module, int level,
509 const char *format, ...)
510 ISC_FORMAT_PRINTF(5, 6);
512 * Write a message to the log channels.
515 * Log messages containing natural language text should be logged with
516 * isc_log_iwrite() to allow for localization.
518 * lctx can be NULL; this is allowed so that programs which use
519 * libraries that use the ISC logging system are not required to
522 * The format argument is a printf(3) string, with additional arguments
526 * lctx is a valid logging context.
528 * The category and module arguments must have ids that are in the
529 * range of known ids, as estabished by isc_log_registercategories()
530 * and isc_log_registermodules().
532 * level != ISC_LOG_DYNAMIC. ISC_LOG_DYNAMIC is used only to define
533 * channels, and explicit debugging level must be identified for
534 * isc_log_write() via ISC_LOG_DEBUG(level).
539 * The log message is written to every channel associated with the
540 * indicated category/module pair.
543 * Nothing. Failure to log a message is not construed as a
548 isc_log_vwrite(isc_log_t *lctx, isc_logcategory_t *category,
549 isc_logmodule_t *module, int level,
550 const char *format, va_list args)
551 ISC_FORMAT_PRINTF(5, 0);
553 * Write a message to the log channels.
556 * lctx can be NULL; this is allowed so that programs which use
557 * libraries that use the ISC logging system are not required to
560 * The format argument is a printf(3) string, with additional arguments
564 * lctx is a valid logging context.
566 * The category and module arguments must have ids that are in the
567 * range of known ids, as estabished by isc_log_registercategories()
568 * and isc_log_registermodules().
570 * level != ISC_LOG_DYNAMIC. ISC_LOG_DYNAMIC is used only to define
571 * channels, and explicit debugging level must be identified for
572 * isc_log_write() via ISC_LOG_DEBUG(level).
577 * The log message is written to every channel associated with the
578 * indicated category/module pair.
581 * Nothing. Failure to log a message is not construed as a
586 isc_log_write1(isc_log_t *lctx, isc_logcategory_t *category,
587 isc_logmodule_t *module, int level, const char *format, ...)
588 ISC_FORMAT_PRINTF(5, 6);
590 * Write a message to the log channels, pruning duplicates that occur within
591 * a configurable amount of seconds (see isc_log_[sg]etduplicateinterval).
592 * This function is otherwise identical to isc_log_write().
596 isc_log_vwrite1(isc_log_t *lctx, isc_logcategory_t *category,
597 isc_logmodule_t *module, int level, const char *format,
599 ISC_FORMAT_PRINTF(5, 0);
601 * Write a message to the log channels, pruning duplicates that occur within
602 * a configurable amount of seconds (see isc_log_[sg]etduplicateinterval).
603 * This function is otherwise identical to isc_log_vwrite().
607 isc_log_iwrite(isc_log_t *lctx, isc_logcategory_t *category,
608 isc_logmodule_t *module, int level,
609 isc_msgcat_t *msgcat, int msgset, int message,
610 const char *format, ...)
611 ISC_FORMAT_PRINTF(8, 9);
614 isc_log_ivwrite(isc_log_t *lctx, isc_logcategory_t *category,
615 isc_logmodule_t *module, int level,
616 isc_msgcat_t *msgcat, int msgset, int message,
617 const char *format, va_list args)
618 ISC_FORMAT_PRINTF(8, 0);
621 isc_log_iwrite1(isc_log_t *lctx, isc_logcategory_t *category,
622 isc_logmodule_t *module, int level,
623 isc_msgcat_t *msgcat, int msgset, int message,
624 const char *format, ...)
625 ISC_FORMAT_PRINTF(8, 9);
628 isc_log_ivwrite1(isc_log_t *lctx, isc_logcategory_t *category,
629 isc_logmodule_t *module, int level,
630 isc_msgcat_t *msgcat, int msgset, int message,
631 const char *format, va_list args)
632 ISC_FORMAT_PRINTF(8, 0);
634 * These are four internationalized versions of the the isc_log_[v]write[1]
635 * functions. The only difference is that they take arguments for a message
636 * catalog, message set, and message number, all immediately preceding the
637 * format argument. The format argument becomes the default text, a la
638 * isc_msgcat_get. If the message catalog is NULL, no lookup is attempted
639 * for a message -- which makes the message set and message number irrelevant,
640 * and the non-internationalized call should have probably been used instead.
642 * Yes, that means there are now *eight* interfaces to logging a message.
643 * Sheesh. Make the madness stop!
647 isc_log_setdebuglevel(isc_log_t *lctx, unsigned int level);
649 * Set the debugging level used for logging.
652 * Setting the debugging level to 0 disables debugging log messages.
655 * lctx is a valid logging context.
658 * The debugging level is set to the requested value.
662 isc_log_getdebuglevel(isc_log_t *lctx);
664 * Get the current debugging level.
667 * This is provided so that a program can have a notion of
668 * "increment debugging level" or "decrement debugging level"
669 * without needing to keep track of what the current level is.
671 * A return value of 0 indicates that debugging messages are disabled.
674 * lctx is a valid logging context.
677 * The current logging debugging level is returned.
681 isc_log_wouldlog(isc_log_t *lctx, int level);
683 * Determine whether logging something to 'lctx' at 'level' would
684 * actually cause something to be logged somewhere.
686 * If ISC_FALSE is returned, it is guaranteed that nothing would
687 * be logged, allowing the caller to omit unnecessary
688 * isc_log_write() calls and possible message preformatting.
692 isc_log_setduplicateinterval(isc_logconfig_t *lcfg, unsigned int interval);
694 * Set the interval over which duplicate log messages will be ignored
695 * by isc_log_[v]write1(), in seconds.
698 * Increasing the duplicate interval from X to Y will not necessarily
699 * filter out duplicates of messages logged in Y - X seconds since the
700 * increase. (Example: Message1 is logged at midnight. Message2
701 * is logged at 00:01:00, when the interval is only 30 seconds, causing
702 * Message1 to be expired from the log message history. Then the interval
703 * is increased to 3000 (five minutes) and at 00:04:00 Message1 is logged
704 * again. It will appear the second time even though less than five
705 * passed since the first occurrence.
708 * lctx is a valid logging context.
712 isc_log_getduplicateinterval(isc_logconfig_t *lcfg);
714 * Get the current duplicate filtering interval.
717 * lctx is a valid logging context.
720 * The current duplicate filtering interval.
724 isc_log_settag(isc_logconfig_t *lcfg, const char *tag);
726 * Set the program name or other identifier for ISC_LOG_PRINTTAG.
729 * lcfg is a valid logging configuration.
732 * If this function has not set the tag to a non-NULL, non-empty value,
733 * then the ISC_LOG_PRINTTAG channel flag will not print anything.
734 * Unlike some implementations of syslog on Unix systems, you *must* set
735 * the tag in order to get it logged. It is not implicitly derived from
736 * the program name (which is pretty impossible to infer portably).
738 * Setting the tag to NULL or the empty string will also cause the
739 * ISC_LOG_PRINTTAG channel flag to not print anything. If tag equals the
740 * empty string, calls to isc_log_gettag will return NULL.
742 * Because the name is used by ISC_LOG_PRINTTAG, it should not be
743 * altered or destroyed after isc_log_settag().
746 * ISC_R_SUCCESS Success
747 * ISC_R_NOMEMORY Resource Limit: Out of memory
749 * XXXDCL when creating a new isc_logconfig_t, it might be nice if the tag
750 * of the currently active isc_logconfig_t was inherited. this does not
755 isc_log_gettag(isc_logconfig_t *lcfg);
757 * Get the current identifier printed with ISC_LOG_PRINTTAG.
760 * lcfg is a valid logging configuration.
763 * Since isc_log_settag() will not associate a zero-length string
764 * with the logging configuration, attempts to do so will cause
765 * this function to return NULL. However, a determined programmer
766 * will observe that (currently) a tag of length greater than zero
767 * could be set, and then modified to be zero length.
770 * A pointer to the current identifier, or NULL if none has been set.
774 isc_log_opensyslog(const char *tag, int options, int facility);
776 * Initialize syslog logging.
780 * This is currently equivalent to openlog(), but is not going to remain
781 * that way. In the meantime, the arguments are all identical to
782 * those used by openlog(3), as follows:
783 * tag: The string to use in the position of the program
784 * name in syslog messages. Most (all?) syslogs
785 * will use basename(argv[0]) if tag is NULL.
787 * options: LOG_CONS, LOG_PID, LOG_NDELAY ... whatever your
790 * facility: The default syslog facility. This is irrelevant
791 * since isc_log_write will ALWAYS use the channel's
794 * Zero effort has been made (yet) to accomodate systems with openlog()
795 * that only takes two arguments, or to identify valid syslog
796 * facilities or options for any given architecture.
798 * It is necessary to call isc_log_opensyslog() to initialize
799 * syslogging on machines which do not support network connections to
800 * syslogd because they require a Unix domain socket to be used. Since
801 * this is a chore to determine at run-time, it is suggested that it
802 * always be called by programs using the ISC logging system.
808 * openlog() is called to initialize the syslog system.
812 isc_log_closefilelogs(isc_log_t *lctx);
814 * Close all open files used by ISC_LOG_TOFILE channels.
817 * This function is provided for programs that want to use their own
818 * log rolling mechanism rather than the one provided internally.
819 * For example, a program that wanted to keep daily logs would define
820 * a channel which used ISC_LOG_ROLLNEVER, then once a day would
821 * rename the log file and call isc_log_closefilelogs().
823 * ISC_LOG_TOFILEDESC channels are unaffected.
826 * lctx is a valid context.
829 * The open files are closed and will be reopened when they are
834 isc_log_categorybyname(isc_log_t *lctx, const char *name);
836 * Find a category by its name.
839 * The string name of a category is not required to be unique.
842 * lctx is a valid context.
846 * A pointer to the _first_ isc_logcategory_t structure used by "name".
848 * NULL if no category exists by that name.
852 isc_log_modulebyname(isc_log_t *lctx, const char *name);
854 * Find a module by its name.
857 * The string name of a module is not required to be unique.
860 * lctx is a valid context.
864 * A pointer to the _first_ isc_logmodule_t structure used by "name".
866 * NULL if no module exists by that name.
870 isc_log_setcontext(isc_log_t *lctx);
872 * Sets the context used by the libisc for logging.
875 * lctx be a valid context.
880 #endif /* ISC_LOG_H */