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- /*
- * Copyright (C) 2004, 2005 Internet Systems Consortium, Inc. ("ISC")
- * Copyright (C) 1999-2002 Internet Software Consortium.
- *
- * Permission to use, copy, modify, and distribute this software for any
- * purpose with or without fee is hereby granted, provided that the above
- * copyright notice and this permission notice appear in all copies.
- *
- * THE SOFTWARE IS PROVIDED "AS IS" AND ISC DISCLAIMS ALL WARRANTIES WITH
- * REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY
- * AND FITNESS. IN NO EVENT SHALL ISC BE LIABLE FOR ANY SPECIAL, DIRECT,
- * INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM
- * LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE
- * OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR
- * PERFORMANCE OF THIS SOFTWARE.
- */
-
- /* $Id: log.h,v 1.47.18.3 2005/04/29 00:16:58 marka Exp $ */
-
- #ifndef ISC_LOG_H
- #define ISC_LOG_H 1
-
- /*! \file */
-
- #include <stdio.h>
- #include <stdarg.h>
- #include <syslog.h> /* XXXDCL NT */
-
- #include <isc/formatcheck.h>
- #include <isc/lang.h>
- #include <isc/platform.h>
- #include <isc/types.h>
-
- /*@{*/
- /*!
- * \brief Severity levels, patterned after Unix's syslog levels.
- *
- */
- #define ISC_LOG_DEBUG(level) (level)
- /*!
- * #ISC_LOG_DYNAMIC can only be used for defining channels with
- * isc_log_createchannel(), not to specify a level in isc_log_write().
- */
- #define ISC_LOG_DYNAMIC 0
- #define ISC_LOG_INFO (-1)
- #define ISC_LOG_NOTICE (-2)
- #define ISC_LOG_WARNING (-3)
- #define ISC_LOG_ERROR (-4)
- #define ISC_LOG_CRITICAL (-5)
- /*@}*/
-
- /*@{*/
- /*!
- * \brief Destinations.
- */
- #define ISC_LOG_TONULL 1
- #define ISC_LOG_TOSYSLOG 2
- #define ISC_LOG_TOFILE 3
- #define ISC_LOG_TOFILEDESC 4
- /*@}*/
-
- /*@{*/
- /*%
- * Channel flags.
- */
- #define ISC_LOG_PRINTTIME 0x0001
- #define ISC_LOG_PRINTLEVEL 0x0002
- #define ISC_LOG_PRINTCATEGORY 0x0004
- #define ISC_LOG_PRINTMODULE 0x0008
- #define ISC_LOG_PRINTTAG 0x0010
- #define ISC_LOG_PRINTALL 0x001F
- #define ISC_LOG_DEBUGONLY 0x1000
- #define ISC_LOG_OPENERR 0x8000 /* internal */
- /*@}*/
-
- /*@{*/
- /*!
- * \brief Other options.
- *
- * XXXDCL INFINITE doesn't yet work. Arguably it isn't needed, but
- * since I am intend to make large number of versions work efficiently,
- * INFINITE is going to be trivial to add to that.
- */
- #define ISC_LOG_ROLLINFINITE (-1)
- #define ISC_LOG_ROLLNEVER (-2)
- /*@}*/
-
- /*!
- * \brief Used to name the categories used by a library.
- *
- * An array of isc_logcategory
- * structures names each category, and the id value is initialized by calling
- * isc_log_registercategories.
- */
- struct isc_logcategory {
- const char *name;
- unsigned int id;
- };
-
- /*%
- * Similar to isc_logcategory, but for all the modules a library defines.
- */
- struct isc_logmodule {
- const char *name;
- unsigned int id;
- };
-
- /*%
- * The isc_logfile structure is initialized as part of an isc_logdestination
- * before calling isc_log_createchannel().
- *
- * When defining an #ISC_LOG_TOFILE
- * channel the name, versions and maximum_size should be set before calling
- * isc_log_createchannel(). To define an #ISC_LOG_TOFILEDESC channel set only
- * the stream before the call.
- *
- * Setting maximum_size to zero implies no maximum.
- */
- typedef struct isc_logfile {
- FILE *stream; /*%< Initialized to NULL for #ISC_LOG_TOFILE. */
- const char *name; /*%< NULL for #ISC_LOG_TOFILEDESC. */
- int versions; /* >= 0, #ISC_LOG_ROLLNEVER, #ISC_LOG_ROLLINFINITE. */
- /*%
- * stdio's ftell is standardized to return a long, which may well not
- * be big enough for the largest file supportable by the operating
- * system (though it is _probably_ big enough for the largest log
- * anyone would want). st_size returned by fstat should be typedef'd
- * to a size large enough for the largest possible file on a system.
- */
- isc_offset_t maximum_size;
- isc_boolean_t maximum_reached; /*%< Private. */
- } isc_logfile_t;
-
- /*%
- * Passed to isc_log_createchannel to define the attributes of either
- * a stdio or a syslog log.
- */
- typedef union isc_logdestination {
- isc_logfile_t file;
- int facility; /* XXXDCL NT */
- } isc_logdestination_t;
-
- /*@{*/
- /*%
- * The built-in categories of libisc.
- *
- * Each library registering categories should provide library_LOGCATEGORY_name
- * definitions with indexes into its isc_logcategory structure corresponding to
- * the order of the names.
- */
- LIBISC_EXTERNAL_DATA extern isc_logcategory_t isc_categories[];
- LIBISC_EXTERNAL_DATA extern isc_log_t *isc_lctx;
- LIBISC_EXTERNAL_DATA extern isc_logmodule_t isc_modules[];
- /*@}*/
-
- /*@{*/
- /*%
- * Do not log directly to DEFAULT. Use another category. When in doubt,
- * use GENERAL.
- */
- #define ISC_LOGCATEGORY_DEFAULT (&isc_categories[0])
- #define ISC_LOGCATEGORY_GENERAL (&isc_categories[1])
- /*@}*/
-
- #define ISC_LOGMODULE_SOCKET (&isc_modules[0])
- #define ISC_LOGMODULE_TIME (&isc_modules[1])
- #define ISC_LOGMODULE_INTERFACE (&isc_modules[2])
- #define ISC_LOGMODULE_TIMER (&isc_modules[3])
-
- ISC_LANG_BEGINDECLS
-
- isc_result_t
- isc_log_create(isc_mem_t *mctx, isc_log_t **lctxp, isc_logconfig_t **lcfgp);
- /*%<
- * Establish a new logging context, with default channels.
- *
- * Notes:
- *\li isc_log_create() calls isc_logconfig_create(), so see its comment
- * below for more information.
- *
- * Requires:
- *\li mctx is a valid memory context.
- *\li lctxp is not null and *lctxp is null.
- *\li lcfgp is null or lcfgp is not null and *lcfgp is null.
- *
- * Ensures:
- *\li *lctxp will point to a valid logging context if all of the necessary
- * memory was allocated, or NULL otherwise.
- *\li *lcfgp will point to a valid logging configuration if all of the
- * necessary memory was allocated, or NULL otherwise.
- *\li On failure, no additional memory is allocated.
- *
- * Returns:
- *\li #ISC_R_SUCCESS Success
- *\li #ISC_R_NOMEMORY Resource limit: Out of memory
- */
-
- isc_result_t
- isc_logconfig_create(isc_log_t *lctx, isc_logconfig_t **lcfgp);
- /*%<
- * Create the data structure that holds all of the configurable information
- * about where messages are actually supposed to be sent -- the information
- * that could changed based on some configuration file, as opposed to the
- * the category/module specification of isc_log_[v]write[1] that is compiled
- * into a program, or the debug_level which is dynamic state information.
- *
- * Notes:
- *\li It is necessary to specify the logging context the configuration
- * will be used with because the number of categories and modules
- * needs to be known in order to set the configuration. However,
- * the configuration is not used by the logging context until the
- * isc_logconfig_use function is called.
- *
- *\li The memory context used for operations that allocate memory for
- * the configuration is that of the logging context, as specified
- * in the isc_log_create call.
- *
- *\li Four default channels are established:
- *\verbatim
- * default_syslog
- * - log to syslog's daemon facility #ISC_LOG_INFO or higher
- * default_stderr
- * - log to stderr #ISC_LOG_INFO or higher
- * default_debug
- * - log to stderr #ISC_LOG_DEBUG dynamically
- * null
- * - log nothing
- *\endverbatim
- *
- * Requires:
- *\li lctx is a valid logging context.
- *\li lcftp is not null and *lcfgp is null.
- *
- * Ensures:
- *\li *lcfgp will point to a valid logging context if all of the necessary
- * memory was allocated, or NULL otherwise.
- *\li On failure, no additional memory is allocated.
- *
- * Returns:
- *\li #ISC_R_SUCCESS Success
- *\li #ISC_R_NOMEMORY Resource limit: Out of memory
- */
-
- isc_logconfig_t *
- isc_logconfig_get(isc_log_t *lctx);
- /*%<
- * Returns a pointer to the configuration currently in use by the log context.
- *
- * Requires:
- *\li lctx is a valid context.
- *
- * Ensures:
- *\li The configuration pointer is non-null.
- *
- * Returns:
- *\li The configuration pointer.
- */
-
- isc_result_t
- isc_logconfig_use(isc_log_t *lctx, isc_logconfig_t *lcfg);
- /*%<
- * Associate a new configuration with a logging context.
- *
- * Notes:
- *\li This is thread safe. The logging context will lock a mutex
- * before attempting to swap in the new configuration, and isc_log_doit
- * (the internal function used by all of isc_log_[v]write[1]) locks
- * the same lock for the duration of its use of the configuration.
- *
- * Requires:
- *\li lctx is a valid logging context.
- *\li lcfg is a valid logging configuration.
- *\li lctx is the same configuration given to isc_logconfig_create
- * when the configuration was created.
- *
- * Ensures:
- *\li Future calls to isc_log_write will use the new configuration.
- *
- * Returns:
- *\li #ISC_R_SUCCESS Success
- *\li #ISC_R_NOMEMORY Resource limit: Out of memory
- */
-
- void
- isc_log_destroy(isc_log_t **lctxp);
- /*%<
- * Deallocate the memory associated with a logging context.
- *
- * Requires:
- *\li *lctx is a valid logging context.
- *
- * Ensures:
- *\li All of the memory associated with the logging context is returned
- * to the free memory pool.
- *
- *\li Any open files are closed.
- *
- *\li The logging context is marked as invalid.
- */
-
- void
- isc_logconfig_destroy(isc_logconfig_t **lcfgp);
- /*%<
- * Destroy a logging configuration.
- *
- * Notes:
- *\li This function cannot be used directly with the return value of
- * isc_logconfig_get, because a logging context must always have
- * a valid configuration associated with it.
- *
- * Requires:
- *\li lcfgp is not null and *lcfgp is a valid logging configuration.
- *\li The logging configuration is not in use by an existing logging context.
- *
- * Ensures:
- *\li All memory allocated for the configuration is freed.
- *
- *\li The configuration is marked as invalid.
- */
-
- void
- isc_log_registercategories(isc_log_t *lctx, isc_logcategory_t categories[]);
- /*%<
- * Identify logging categories a library will use.
- *
- * Notes:
- *\li A category should only be registered once, but no mechanism enforces
- * this rule.
- *
- *\li The end of the categories array is identified by a NULL name.
- *
- *\li Because the name is used by #ISC_LOG_PRINTCATEGORY, it should not
- * be altered or destroyed after isc_log_registercategories().
- *
- *\li Because each element of the categories array is used by
- * isc_log_categorybyname, it should not be altered or destroyed
- * after registration.
- *
- *\li The value of the id integer in each structure is overwritten
- * by this function, and so id need not be initialized to any particular
- * value prior to the function call.
- *
- *\li A subsequent call to isc_log_registercategories with the same
- * logging context (but new categories) will cause the last
- * element of the categories array from the prior call to have
- * its "name" member changed from NULL to point to the new
- * categories array, and its "id" member set to UINT_MAX.
- *
- * Requires:
- *\li lctx is a valid logging context.
- *\li categories != NULL.
- *\li categories[0].name != NULL.
- *
- * Ensures:
- * \li There are references to each category in the logging context,
- * so they can be used with isc_log_usechannel() and isc_log_write().
- */
-
- void
- isc_log_registermodules(isc_log_t *lctx, isc_logmodule_t modules[]);
- /*%<
- * Identify logging categories a library will use.
- *
- * Notes:
- *\li A module should only be registered once, but no mechanism enforces
- * this rule.
- *
- *\li The end of the modules array is identified by a NULL name.
- *
- *\li Because the name is used by #ISC_LOG_PRINTMODULE, it should not
- * be altered or destroyed after isc_log_registermodules().
- *
- *\li Because each element of the modules array is used by
- * isc_log_modulebyname, it should not be altered or destroyed
- * after registration.
- *
- *\li The value of the id integer in each structure is overwritten
- * by this function, and so id need not be initialized to any particular
- * value prior to the function call.
- *
- *\li A subsequent call to isc_log_registermodules with the same
- * logging context (but new modules) will cause the last
- * element of the modules array from the prior call to have
- * its "name" member changed from NULL to point to the new
- * modules array, and its "id" member set to UINT_MAX.
- *
- * Requires:
- *\li lctx is a valid logging context.
- *\li modules != NULL.
- *\li modules[0].name != NULL;
- *
- * Ensures:
- *\li Each module has a reference in the logging context, so they can be
- * used with isc_log_usechannel() and isc_log_write().
- */
-
- isc_result_t
- isc_log_createchannel(isc_logconfig_t *lcfg, const char *name,
- unsigned int type, int level,
- const isc_logdestination_t *destination,
- unsigned int flags);
- /*%<
- * Specify the parameters of a logging channel.
- *
- * Notes:
- *\li The name argument is copied to memory in the logging context, so
- * it can be altered or destroyed after isc_log_createchannel().
- *
- *\li Defining a very large number of channels will have a performance
- * impact on isc_log_usechannel(), since the names are searched
- * linearly until a match is made. This same issue does not affect
- * isc_log_write, however.
- *
- *\li Channel names can be redefined; this is primarily useful for programs
- * that want their own definition of default_syslog, default_debug
- * and default_stderr.
- *
- *\li Any channel that is redefined will not affect logging that was
- * already directed to its original definition, _except_ for the
- * default_stderr channel. This case is handled specially so that
- * the default logging category can be changed by redefining
- * default_stderr. (XXXDCL Though now that I think of it, the default
- * logging category can be changed with only one additional function
- * call by defining a new channel and then calling isc_log_usechannel()
- * for #ISC_LOGCATEGORY_DEFAULT.)
- *
- *\li Specifying #ISC_LOG_PRINTTIME or #ISC_LOG_PRINTTAG for syslog is allowed,
- * but probably not what you wanted to do.
- *
- * #ISC_LOG_DEBUGONLY will mark the channel as usable only when the
- * debug level of the logging context (see isc_log_setdebuglevel)
- * is non-zero.
- *
- * Requires:
- *\li lcfg is a valid logging configuration.
- *
- *\li name is not NULL.
- *
- *\li type is #ISC_LOG_TOSYSLOG, #ISC_LOG_TOFILE, #ISC_LOG_TOFILEDESC or
- * #ISC_LOG_TONULL.
- *
- *\li destination is not NULL unless type is #ISC_LOG_TONULL.
- *
- *\li level is >= #ISC_LOG_CRITICAL (the most negative logging level).
- *
- *\li flags does not include any bits aside from the ISC_LOG_PRINT* bits
- * or #ISC_LOG_DEBUGONLY.
- *
- * Ensures:
- *\li #ISC_R_SUCCESS
- * A channel with the given name is usable with
- * isc_log_usechannel().
- *
- *\li #ISC_R_NOMEMORY or #ISC_R_UNEXPECTED
- * No additional memory is being used by the logging context.
- * Any channel that previously existed with the given name
- * is not redefined.
- *
- * Returns:
- *\li #ISC_R_SUCCESS Success
- *\li #ISC_R_NOMEMORY Resource limit: Out of memory
- *\li #ISC_R_UNEXPECTED type was out of range and REQUIRE()
- * was disabled.
- */
-
- isc_result_t
- isc_log_usechannel(isc_logconfig_t *lcfg, const char *name,
- const isc_logcategory_t *category,
- const isc_logmodule_t *module);
- /*%<
- * Associate a named logging channel with a category and module that
- * will use it.
- *
- * Notes:
- *\li The name is searched for linearly in the set of known channel names
- * until a match is found. (Note the performance impact of a very large
- * number of named channels.) When multiple channels of the same
- * name are defined, the most recent definition is found.
- *
- *\li Specifing a very large number of channels for a category will have
- * a moderate impact on performance in isc_log_write(), as each
- * call looks up the category for the start of a linked list, which
- * it follows all the way to the end to find matching modules. The
- * test for matching modules is integral, though.
- *
- *\li If category is NULL, then the channel is associated with the indicated
- * module for all known categories (including the "default" category).
- *
- *\li If module is NULL, then the channel is associated with every module
- * that uses that category.
- *
- *\li Passing both category and module as NULL would make every log message
- * use the indicated channel.
- *
- * \li Specifying a channel that is #ISC_LOG_TONULL for a category/module pair
- * has no effect on any other channels associated with that pair,
- * regardless of ordering. Thus you cannot use it to "mask out" one
- * category/module pair when you have specified some other channel that
- * is also used by that category/module pair.
- *
- * Requires:
- *\li lcfg is a valid logging configuration.
- *
- *\li category is NULL or has an id that is in the range of known ids.
- *
- * module is NULL or has an id that is in the range of known ids.
- *
- * Ensures:
- *\li #ISC_R_SUCCESS
- * The channel will be used by the indicated category/module
- * arguments.
- *
- *\li #ISC_R_NOMEMORY
- * If assignment for a specific category has been requested,
- * the channel has not been associated with the indicated
- * category/module arguments and no additional memory is
- * used by the logging context.
- * If assignment for all categories has been requested
- * then _some_ may have succeeded (starting with category
- * "default" and progressing through the order of categories
- * passed to isc_log_registercategories()) and additional memory
- * is being used by whatever assignments succeeded.
- *
- * Returns:
- *\li #ISC_R_SUCCESS Success
- *\li #ISC_R_NOMEMORY Resource limit: Out of memory
- */
-
- /* Attention: next four comments PRECEED code */
- /*!
- * \brief
- * Write a message to the log channels.
- *
- * Notes:
- *\li Log messages containing natural language text should be logged with
- * isc_log_iwrite() to allow for localization.
- *
- *\li lctx can be NULL; this is allowed so that programs which use
- * libraries that use the ISC logging system are not required to
- * also use it.
- *
- *\li The format argument is a printf(3) string, with additional arguments
- * as necessary.
- *
- * Requires:
- *\li lctx is a valid logging context.
- *
- *\li The category and module arguments must have ids that are in the
- * range of known ids, as estabished by isc_log_registercategories()
- * and isc_log_registermodules().
- *
- *\li level != #ISC_LOG_DYNAMIC. ISC_LOG_DYNAMIC is used only to define
- * channels, and explicit debugging level must be identified for
- * isc_log_write() via ISC_LOG_DEBUG(level).
- *
- *\li format != NULL.
- *
- * Ensures:
- *\li The log message is written to every channel associated with the
- * indicated category/module pair.
- *
- * Returns:
- *\li Nothing. Failure to log a message is not construed as a
- * meaningful error.
- */
- void
- isc_log_write(isc_log_t *lctx, isc_logcategory_t *category,
- isc_logmodule_t *module, int level,
- const char *format, ...)
-
- ISC_FORMAT_PRINTF(5, 6);
-
- /*%
- * Write a message to the log channels.
- *
- * Notes:
- *\li lctx can be NULL; this is allowed so that programs which use
- * libraries that use the ISC logging system are not required to
- * also use it.
- *
- *\li The format argument is a printf(3) string, with additional arguments
- * as necessary.
- *
- * Requires:
- *\li lctx is a valid logging context.
- *
- *\li The category and module arguments must have ids that are in the
- * range of known ids, as estabished by isc_log_registercategories()
- * and isc_log_registermodules().
- *
- *\li level != #ISC_LOG_DYNAMIC. ISC_LOG_DYNAMIC is used only to define
- * channels, and explicit debugging level must be identified for
- * isc_log_write() via ISC_LOG_DEBUG(level).
- *
- *\li format != NULL.
- *
- * Ensures:
- *\li The log message is written to every channel associated with the
- * indicated category/module pair.
- *
- * Returns:
- *\li Nothing. Failure to log a message is not construed as a
- * meaningful error.
- */
- void
- isc_log_vwrite(isc_log_t *lctx, isc_logcategory_t *category,
- isc_logmodule_t *module, int level,
- const char *format, va_list args)
-
- ISC_FORMAT_PRINTF(5, 0);
-
- /*%
- * Write a message to the log channels, pruning duplicates that occur within
- * a configurable amount of seconds (see isc_log_[sg]etduplicateinterval).
- * This function is otherwise identical to isc_log_write().
- */
- void
- isc_log_write1(isc_log_t *lctx, isc_logcategory_t *category,
- isc_logmodule_t *module, int level, const char *format, ...)
-
- ISC_FORMAT_PRINTF(5, 6);
-
- /*%
- * Write a message to the log channels, pruning duplicates that occur within
- * a configurable amount of seconds (see isc_log_[sg]etduplicateinterval).
- * This function is otherwise identical to isc_log_vwrite().
- */
- void
- isc_log_vwrite1(isc_log_t *lctx, isc_logcategory_t *category,
- isc_logmodule_t *module, int level, const char *format,
- va_list args)
-
- ISC_FORMAT_PRINTF(5, 0);
-
- /*%
- * These are four internationalized versions of the the isc_log_[v]write[1]
- * functions.
- *
- * The only difference is that they take arguments for a message
- * catalog, message set, and message number, all immediately preceding the
- * format argument. The format argument becomes the default text, a la
- * isc_msgcat_get. If the message catalog is NULL, no lookup is attempted
- * for a message -- which makes the message set and message number irrelevant,
- * and the non-internationalized call should have probably been used instead.
- *
- * Yes, that means there are now *eight* interfaces to logging a message.
- * Sheesh. Make the madness stop!
- */
- /*@{*/
- void
- isc_log_iwrite(isc_log_t *lctx, isc_logcategory_t *category,
- isc_logmodule_t *module, int level,
- isc_msgcat_t *msgcat, int msgset, int message,
- const char *format, ...)
- ISC_FORMAT_PRINTF(8, 9);
-
- void
- isc_log_ivwrite(isc_log_t *lctx, isc_logcategory_t *category,
- isc_logmodule_t *module, int level,
- isc_msgcat_t *msgcat, int msgset, int message,
- const char *format, va_list args)
- ISC_FORMAT_PRINTF(8, 0);
-
- void
- isc_log_iwrite1(isc_log_t *lctx, isc_logcategory_t *category,
- isc_logmodule_t *module, int level,
- isc_msgcat_t *msgcat, int msgset, int message,
- const char *format, ...)
- ISC_FORMAT_PRINTF(8, 9);
-
- void
- isc_log_ivwrite1(isc_log_t *lctx, isc_logcategory_t *category,
- isc_logmodule_t *module, int level,
- isc_msgcat_t *msgcat, int msgset, int message,
- const char *format, va_list args)
- ISC_FORMAT_PRINTF(8, 0);
- /*@}*/
-
- void
- isc_log_setdebuglevel(isc_log_t *lctx, unsigned int level);
- /*%<
- * Set the debugging level used for logging.
- *
- * Notes:
- *\li Setting the debugging level to 0 disables debugging log messages.
- *
- * Requires:
- *\li lctx is a valid logging context.
- *
- * Ensures:
- *\li The debugging level is set to the requested value.
- */
-
- unsigned int
- isc_log_getdebuglevel(isc_log_t *lctx);
- /*%<
- * Get the current debugging level.
- *
- * Notes:
- *\li This is provided so that a program can have a notion of
- * "increment debugging level" or "decrement debugging level"
- * without needing to keep track of what the current level is.
- *
- *\li A return value of 0 indicates that debugging messages are disabled.
- *
- * Requires:
- *\li lctx is a valid logging context.
- *
- * Ensures:
- *\li The current logging debugging level is returned.
- */
-
- isc_boolean_t
- isc_log_wouldlog(isc_log_t *lctx, int level);
- /*%<
- * Determine whether logging something to 'lctx' at 'level' would
- * actually cause something to be logged somewhere.
- *
- * If #ISC_FALSE is returned, it is guaranteed that nothing would
- * be logged, allowing the caller to omit unnecessary
- * isc_log_write() calls and possible message preformatting.
- */
-
- void
- isc_log_setduplicateinterval(isc_logconfig_t *lcfg, unsigned int interval);
- /*%<
- * Set the interval over which duplicate log messages will be ignored
- * by isc_log_[v]write1(), in seconds.
- *
- * Notes:
- *\li Increasing the duplicate interval from X to Y will not necessarily
- * filter out duplicates of messages logged in Y - X seconds since the
- * increase. (Example: Message1 is logged at midnight. Message2
- * is logged at 00:01:00, when the interval is only 30 seconds, causing
- * Message1 to be expired from the log message history. Then the interval
- * is increased to 3000 (five minutes) and at 00:04:00 Message1 is logged
- * again. It will appear the second time even though less than five
- * passed since the first occurrence.
- *
- * Requires:
- *\li lctx is a valid logging context.
- */
-
- unsigned int
- isc_log_getduplicateinterval(isc_logconfig_t *lcfg);
- /*%<
- * Get the current duplicate filtering interval.
- *
- * Requires:
- *\li lctx is a valid logging context.
- *
- * Returns:
- *\li The current duplicate filtering interval.
- */
-
- isc_result_t
- isc_log_settag(isc_logconfig_t *lcfg, const char *tag);
- /*%<
- * Set the program name or other identifier for #ISC_LOG_PRINTTAG.
- *
- * Requires:
- *\li lcfg is a valid logging configuration.
- *
- * Notes:
- *\li If this function has not set the tag to a non-NULL, non-empty value,
- * then the #ISC_LOG_PRINTTAG channel flag will not print anything.
- * Unlike some implementations of syslog on Unix systems, you *must* set
- * the tag in order to get it logged. It is not implicitly derived from
- * the program name (which is pretty impossible to infer portably).
- *
- *\li Setting the tag to NULL or the empty string will also cause the
- * #ISC_LOG_PRINTTAG channel flag to not print anything. If tag equals the
- * empty string, calls to isc_log_gettag will return NULL.
- *
- * Returns:
- *\li #ISC_R_SUCCESS Success
- *\li #ISC_R_NOMEMORY Resource Limit: Out of memory
- *
- * XXXDCL when creating a new isc_logconfig_t, it might be nice if the tag
- * of the currently active isc_logconfig_t was inherited. this does not
- * currently happen.
- */
-
- char *
- isc_log_gettag(isc_logconfig_t *lcfg);
- /*%<
- * Get the current identifier printed with #ISC_LOG_PRINTTAG.
- *
- * Requires:
- *\li lcfg is a valid logging configuration.
- *
- * Notes:
- *\li Since isc_log_settag() will not associate a zero-length string
- * with the logging configuration, attempts to do so will cause
- * this function to return NULL. However, a determined programmer
- * will observe that (currently) a tag of length greater than zero
- * could be set, and then modified to be zero length.
- *
- * Returns:
- *\li A pointer to the current identifier, or NULL if none has been set.
- */
-
- void
- isc_log_opensyslog(const char *tag, int options, int facility);
- /*%<
- * Initialize syslog logging.
- *
- * Notes:
- *\li XXXDCL NT
- * This is currently equivalent to openlog(), but is not going to remain
- * that way. In the meantime, the arguments are all identical to
- * those used by openlog(3), as follows:
- *
- * \code
- * tag: The string to use in the position of the program
- * name in syslog messages. Most (all?) syslogs
- * will use basename(argv[0]) if tag is NULL.
- *
- * options: LOG_CONS, LOG_PID, LOG_NDELAY ... whatever your
- * syslog supports.
- *
- * facility: The default syslog facility. This is irrelevant
- * since isc_log_write will ALWAYS use the channel's
- * declared facility.
- * \endcode
- *
- *\li Zero effort has been made (yet) to accomodate systems with openlog()
- * that only takes two arguments, or to identify valid syslog
- * facilities or options for any given architecture.
- *
- *\li It is necessary to call isc_log_opensyslog() to initialize
- * syslogging on machines which do not support network connections to
- * syslogd because they require a Unix domain socket to be used. Since
- * this is a chore to determine at run-time, it is suggested that it
- * always be called by programs using the ISC logging system.
- *
- * Requires:
- *\li Nothing.
- *
- * Ensures:
- *\li openlog() is called to initialize the syslog system.
- */
-
- void
- isc_log_closefilelogs(isc_log_t *lctx);
- /*%<
- * Close all open files used by #ISC_LOG_TOFILE channels.
- *
- * Notes:
- *\li This function is provided for programs that want to use their own
- * log rolling mechanism rather than the one provided internally.
- * For example, a program that wanted to keep daily logs would define
- * a channel which used #ISC_LOG_ROLLNEVER, then once a day would
- * rename the log file and call isc_log_closefilelogs().
- *
- *\li #ISC_LOG_TOFILEDESC channels are unaffected.
- *
- * Requires:
- *\li lctx is a valid context.
- *
- * Ensures:
- *\li The open files are closed and will be reopened when they are
- * next needed.
- */
-
- isc_logcategory_t *
- isc_log_categorybyname(isc_log_t *lctx, const char *name);
- /*%<
- * Find a category by its name.
- *
- * Notes:
- *\li The string name of a category is not required to be unique.
- *
- * Requires:
- *\li lctx is a valid context.
- *\li name is not NULL.
- *
- * Returns:
- *\li A pointer to the _first_ isc_logcategory_t structure used by "name".
- *
- *\li NULL if no category exists by that name.
- */
-
- isc_logmodule_t *
- isc_log_modulebyname(isc_log_t *lctx, const char *name);
- /*%<
- * Find a module by its name.
- *
- * Notes:
- *\li The string name of a module is not required to be unique.
- *
- * Requires:
- *\li lctx is a valid context.
- *\li name is not NULL.
- *
- * Returns:
- *\li A pointer to the _first_ isc_logmodule_t structure used by "name".
- *
- *\li NULL if no module exists by that name.
- */
-
- void
- isc_log_setcontext(isc_log_t *lctx);
- /*%<
- * Sets the context used by the libisc for logging.
- *
- * Requires:
- *\li lctx be a valid context.
- */
-
- ISC_LANG_ENDDECLS
-
- #endif /* ISC_LOG_H */
-