/* -*- c-basic-offset: 4; tab-width: 8; indent-tabs-mode: t -*- */ /* * Copyright (c) 2001-2007 International Computer Science Institute * * Permission is hereby granted, free of charge, to any person obtaining a * copy of this software and associated documentation files (the "Software") * to deal in the Software without restriction, subject to the conditions * listed in the XORP LICENSE file. These conditions include: you must * preserve this copyright notice, and you cannot mention the copyright * holders in advertising related to the Software without their permission. * The Software is provided WITHOUT ANY WARRANTY, EXPRESS OR IMPLIED. This * notice is a summary of the XORP LICENSE file; the license in that file is * legally binding. */ /* * $XORP: xorp/libxorp/xlog.h,v 1.15 2007/02/16 22:46:29 pavlin Exp $ */ #ifndef __LIBXORP_XLOG_H__ #define __LIBXORP_XLOG_H__ #include "libxorp/xorp.h" /* * The following defines and notes we defined __printfike if it does not * already exist. The expansion of this macro uses a gcc extension to * check format strings. */ #ifndef __printflike #ifdef __GNUC__ #define __printflike(fmt,va1) __attribute__((__format__(printf, fmt, va1))) #define __libxorp_xlog_defined_printflike #else #define __printflike(fmt, va1) #define __libxorp_xlog_defined_printflike #endif /* __GNUC__ */ #endif /* __printflike */ /** * @short XORP logging functions. * * The xlog functions provide a similar role to syslog. The log * messages may be output to multiple output streams simulataneously. */ # ifdef __cplusplus extern "C" { # endif /** * The log levels. Typically used only by @ref xlog_enable() * and @ref xlog_disable() */ typedef enum { XLOG_LEVEL_MIN = 0, /* 0 */ XLOG_LEVEL_FATAL = 0, /* 0 */ XLOG_LEVEL_ERROR, /* 1 */ XLOG_LEVEL_WARNING, /* 2 */ XLOG_LEVEL_INFO, /* 3 */ XLOG_LEVEL_TRACE, /* 4 */ XLOG_LEVEL_MAX } xlog_level_t; /** * The messages verbose level. Typically used only by @ref xlog_set_verbose() * and @ref xlog_level_set_verbose() */ typedef enum { XLOG_VERBOSE_LOW = 0, /* 0 */ XLOG_VERBOSE_MEDIUM, /* 1 */ XLOG_VERBOSE_HIGH, /* 2 */ XLOG_VERBOSE_MAX } xlog_verbose_t; /** * The type of add-on functions to process the log messages. */ typedef int (*xlog_output_func_t)(void *obj, const char *msg); /** * A macro used for internal purpose to generate the appropriate xlog code */ #if (!defined XORP_MODULE_NAME) && (!defined XORP_LIBRARY_NAME) #error You MUST have in your local directory a file like #error "foo_module.h" that has defined inside the module #error or library name. E.g.: #define XORP_MODULE_NAME "BGP" #error or #define XORP_LIBRARY_NAME #error This "foo_module.h" must be the first included by #error each *.c and *.cc file. #endif #ifdef XORP_LIBRARY_NAME # define _XLOG_MODULE_NAME XORP_LIBRARY_NAME #else # define _XLOG_MODULE_NAME XORP_MODULE_NAME #endif #define XLOG_FN(fn, fmt...) \ do { \ char xlog_where_buf[8000]; \ sprintf(xlog_where_buf, "+%d %s %s", __LINE__, __FILE__, __FUNCTION__);\ xlog_##fn(_XLOG_MODULE_NAME, xlog_where_buf, fmt); \ } while (0) /** * Initialize the log utility. * * As part of the initialization, the preamble string will be set to * <@ref process_name><@ref preamble_message> * Use in preference to @ref xlog_set_preamble which will be removed. * * @param argv0 the path of the process executable from which the program name * will be extract to become part of the preamble string. * * @param preamble_message a string that will become part of the * preamble string. * * @return 0 on success, otherwise -1. */ int xlog_init(const char *argv0, const char *preamble_message); /** * Gracefully exit logging. * * @return 0 on success, otherwise -1. */ int xlog_exit(void); /** * Start logging. * * @return 0 on success, otherwise -1. */ int xlog_start(void); /** * Stop logging. * * @return 0 on success, otherwise -1. */ int xlog_stop(void); /** * Check if xlog is running. * * @return non-zero if xlog is running, otherwise 0. */ int xlog_is_running(void); /** * Enable logging for messages of a given type (@ref log_level_t). * * By default, all message types are enabled. * * @param log_level the message type @ref xlog_level_t * (e.g., @ref XLOG_LEVEL_WARNING) to enable the logging for. * @return 0 on success, otherwise -1. */ int xlog_enable(xlog_level_t log_level); /** * Disable logging for messages of a given type (@ref log_level_t). * * Note: @ref XLOG_LEVEL_FATAL cannot be disabled. * * @param log_level the message type @ref xlog_level_t * (e.g., @ref XLOG_LEVEL_WARNING) to disable the logging for. * @return 0 on success, otherwise -1. */ int xlog_disable(xlog_level_t log_level); /** * Set the preamble string for the log entries. * * @param text the preamble string, or NULL if no preamble. */ void xlog_set_preamble(const char *text); /** * Get process name as set with xlog_init. * * @return pointer to name on success, NULL otherwise. */ const char* xlog_process_name(void); /** * Set the level of verbosity (@ref xlog_verbose_t) for the log entries. * * Applies for all type of messages except for @ref XLOG_LEVEL_FATAL * which always is set to the most verbose level. * * @param verbose_level the level of verbosity @ref xlog_verbose_t * (higher is more verbose). */ void xlog_set_verbose(xlog_verbose_t verbose_level); /** * Set the level of verbosity (@ref xlog_verbose_t) for the log entries * of messages of a given type (@ref xlog_level_t). * * Note: @ref XLOG_LEVEL_FATAL verbosity cannot be changed, and is * always set to the most verbose level. * * @param log_level the message type @ref xlog_level_t to set the * verbosity of. * @param verbose_level the level of verbosity @ref xlog_verbose_t * (higher is more verbose). */ void xlog_level_set_verbose(xlog_level_t log_level, xlog_verbose_t verbose_level); /** * Add a file descriptor to the set of output streams. * * @param fp the file descriptor to add to the set of output streams. * @return 0 on success, otherwise -1. */ int xlog_add_output(FILE *fp); /** * Remove a file descriptor from the set of output streams. * * @param fp the file descriptor to remove from the set of output streams. * @return 0 on success, otherwise -1. */ int xlog_remove_output(FILE *fp); /** * Add a processing function and an object to the set of output streams. * * @param func the function to add to the set of output streams. * @param obj the object to supply @ref func with when called. * * @return 0 on success, otherwise -1. */ int xlog_add_output_func(xlog_output_func_t func, void *obj); /** * Remove a processing function and an object from the set of output streams. * * @param func the function to remove from the set of output streams. * @param obj the object that @ref func was supplied with. * * @return 0 on success, otherwise -1. */ int xlog_remove_output_func(xlog_output_func_t func, void *obj); /** * Add default output stream to list of output streams. * * XXX: right now the default is '/dev/stderr', but it should eventually be: * `/dev/console' if the process has sufficient permissions, * and `/dev/stderr' otherwise. * * @return 0 on success, otherwise -1. */ int xlog_add_default_output(void); /** * Remove the default output stream from the set of output streams. * * @return 0 on success, otherwise -1. */ int xlog_remove_default_output(void); /** * Write a FATAL message to the xlog output streams and aborts the program. * * Note that FATAL messages cannot be disabled by @ref xlog_disable(). * * @param module_name the name of the module this message applies to. * @param format the printf()-style format of the message to write. * Note that a trailing newline is added if none is present. * @param ... the arguments for @ref format. */ void xlog_fatal(const char *module_name, const char *where, const char *format, ...) __printflike(3,4); #define XLOG_FATAL(fmt...) XLOG_FN(fatal, fmt) /** * Write an ERROR message to the xlog output streams. * * @param module_name the name of the module this message applies to. * @param format the printf()-style format of the message to write. * Note that a trailing newline is added if none is present. * @param ... the arguments for @ref format. */ void xlog_error(const char *module_name, const char *where, const char *format, ...) __printflike(3,4); #define XLOG_ERROR(fmt...) XLOG_FN(error, fmt) /** * Write a WARNING message to the xlog output streams. * * @param module_name the name of the module this message applies to. * @param format the printf()-style format of the message to write. * Note that a trailing newline is added if none is present. * @param ... the arguments for @ref format. */ void xlog_warning(const char *module_name, const char *where, const char *format, ...) __printflike(3,4); #define XLOG_WARNING(fmt...) XLOG_FN(warning, fmt) /** * Write an INFO message to the xlog output streams. * * @param module_name the name of the module this message applies to. * @param format the printf()-style format of the message to write. * Note that a trailing newline is added if none is present. * @param ... the arguments for @ref format. */ void xlog_info(const char *module_name, const char *where, const char *format, ...) __printflike(3,4); #define XLOG_INFO(fmt...) XLOG_FN(info, fmt) /** * XORP replacement for assert(3). * * Note that it cannot be conditionally disabled and logs error through * the standard XLOG mechanism. * Calls XLOG_FATAL if assertion fails. * * @param assertion the assertion condition. */ #define XLOG_ASSERT(assertion) \ do { \ if (!(assertion)) \ XLOG_FATAL("Assertion (%s) failed", #assertion); \ } while (0) /** * A marker that can be used to indicate code that should never be executed. * * Note that it cannot be conditionally disabled and logs error through * the standard XLOG mechanism. * Always calls XLOG_FATAL. */ #define XLOG_UNREACHABLE() \ do { \ XLOG_FATAL("Internal fatal error: unreachable code reached"); \ exit(1); /* unreached: keep the compiler happy */ \ } while (0) /** * A marker that can be used to indicate code that is not yet * implemented and hence should not be run. * * Note that it cannot be conditionally disabled and logs error through * the standard XLOG mechanism. * Always calls XLOG_FATAL. */ #define XLOG_UNFINISHED() \ do { \ XLOG_FATAL("Internal fatal error: unfinished code reached"); \ exit(1); /* unreached: keep the compiler happy */ \ } while (0) /* * The macros below define the XLOG_TRACE(), the macro responsible for * generating trace messages. It takes the same arguments as * printf(), except that the very first argument is a boolean * that defines whether the trace message will be output. * Note that a trailing newline is added if none is present. * E.g., * * XLOG_TRACE(cond_variable, "The number is %d", 5); * * There is some additional unpleasantness in this header for * `configure' related magic. * * The macro CPP_SUPPORTS_VA_ARGS is defined by `configure' tests if the * C preprocessor supports macros with variable length arguments. We * use the GNU specific (args...) syntax for variable length arguments * as the c9x standard (__VA_ARGS__) breaks when the preprocessor is * invoked via g++. * TODO: the magic below should be used for the other XLOG_* entries * as well. */ #ifdef CPP_SUPPORTS_GNU_VA_ARGS # define XLOG_TRACE(args...) \ _xcond_trace_msg_long(XORP_MODULE_NAME, __FILE__, __LINE__, __FUNCTION__, args) #else # define XLOG_TRACE \ _xcond_trace_entry(XORP_MODULE_NAME, __FILE__, __LINE__, __FUNCTION__), \ _xcond_trace_msg_short #endif /* Function for systems with variable argument macros */ void _xcond_trace_msg_long(const char *module_name, const char *file, int line, const char *fn, int flag, const char *format, ...) __printflike(6,7); /* Functions for systems without variable argument macros */ void _xcond_trace_entry(const char *module_name, const char *file, int line, const char *fn); void _xcond_trace_msg_short(int flag, const char *format, ...) __printflike(2,3); /** * Compute the current local time and return it as a string. * * The return string has the format: * Year/Month/Day Hour:Minute:Second.Microsecond * Example: 2002/02/05 20:22:09.808632 * Note that the returned string uses statically allocated memory, * and does not need to be de-allocated. * * @return a statically allocated string with the local time using * the format described above. */ const char *xlog_localtime2string(void); /** * A local implementation of vasprintf(3). * * If vasprintf(3) is available, it is called instead. * * @param ret a pointer to the string pointer to store the result. * @param format the printf(3)-style format. * @param ap the variable arguments for @ref format. * * @return (From FreeBSD vasprintf(3) manual page): * The number of characters printed (not including the trailing '\0' * used to end output to strings). Also, set the value pointed to by * ret to be a pointer to a buffer sufficiently large to hold the * formatted string. This pointer should be passed to free(3) to * release the allocated storage when it is no longer needed. If * sufficient space cannot be allocated, will return -1 and set @ref ret * to be a NULL pointer. */ int x_vasprintf(char **ret, const char *format, va_list ap); /** * A local implementation of asprintf(3). * * @param ret a pointer to the string pointer to store the result. * @param format the printf(3)-style format. * @param ... the variable arguments for @ref format. * * @return (From FreeBSD asprintf(3) manual page): * The number of characters printed (not including the * trailing '\0' used to end output to strings). Also, set ret to be * a pointer to a buffer sufficiently large to hold the formatted string. * This pointer should be passed to free(3) to release the allocated * storage when it is no longer needed. If sufficient space cannot * be allocated, will return -1 and set @ref ret to be a NULL pointer. */ int x_asprintf(char **ret, const char *format, ...); /* Undefine __printflike if we defined it */ #ifdef __libxorp_xlog_defined_printflike #undef __libxorp_xlog_defined_printflike #undef __printflike #endif /* __libxorp_xlog_defined_printflike */ # ifdef __cplusplus } # endif #endif /* __LIBXORP_XLOG_H__ */