PyFCGI/include/logger.h

/*
 * Copyright (C) 2019 Weber Yann
 * 
 * This file is part of PyFCGI.
 * 
 * PyFCGI is free software: you can redistribute it and/or modify
 * it under the terms of the GNU Affero General Public License as published by
 * the Free Software Foundation, either version 3 of the License, or
 * any later version.
 * 
 * PyFCGI is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU Affero General Public License for more details.
 * 
 * You should have received a copy of the GNU Affero General Public License
 * along with PyFCGI.  If not, see <http://www.gnu.org/licenses/>.
 */
#ifndef __LOGGER_H___
#define __LOGGER_H___

#include "config.h"
#include <syslog.h>
#include <stdlib.h>
#include <errno.h>
#include <string.h>
#include <stdarg.h>
#include <unistd.h>
#include <fcntl.h>
#include <stdio.h>
#include <sys/types.h>
#include <sys/stat.h>

/**@file logger.h
 * @brief PyFCGI logging facility
 * @ingroup conf_logger
 */
/**@defgroup conf_logger Logging configuration
 * @ingroup conf_internal
 */

/**@defgroup log_facility Logger custom facilities */
/**@ingroup log_facility */
#define LOG_GLOBAL 0
/**@ingroup log_facility */
#define LOG_ACCESS 1
/**@ingroup log_facility */
#define LOG_INTERN 2
/**@ingroup log_facility */
#define LOG_WORKER 4
/**@ingroup log_facility */
#define LOG_MASTER 8

#define SYSLOG_syslog syslog
#define SYSLOG_vsyslog vsyslog
#define SYSLOG_EMERG   LOG_EMERG
#define SYSLOG_ALERT   LOG_ALERT
#define SYSLOG_CRIT    LOG_CRIT
#define SYSLOG_ERR     LOG_ERR
#define SYSLOG_WARNING LOG_WARNING
#define SYSLOG_NOTICE  LOG_NOTICE
#define SYSLOG_INFO    LOG_INFO
#define SYSLOG_DEBUG   LOG_DEBUG
const short SYSLOG_LVLS[8] = {LOG_EMERG, LOG_ALERT, LOG_CRIT, LOG_ERR,
                              LOG_WARNING, LOG_NOTICE, LOG_INFO, LOG_DEBUG};

#undef LOG_EMERG
#undef LOG_ALERT
#undef LOG_CRIT
#undef LOG_ERR
#undef LOG_WARNING
#undef LOG_NOTICE
#undef LOG_INFO
#undef LOG_DEBUG

/* This way we can mimic syslog and the or'ed level | facility */
//#define LOG_EMERG (1 << 4)
#define LOG_EMERG (2 << 4)
#define LOG_ALERT (2 << 4)
#define LOG_CRIT (3 << 4)
#define LOG_ERR (4 << 4)
#define LOG_WARNING (5 << 4)
#define LOG_NOTICE (6 << 4)
#define LOG_INFO (7 << 4)
#define LOG_DEBUG (8 << 4)

/**@brief Convert a PyFCGI loglevel in a syslog one */
#define PYFCGI_SYSLOG_LVL(lvl) (SYSLOG_LVLS[(lvl & 0xF0) >> 4])

/**@brief Macro checking if syslog is activated and log a message
 * @params int lvl the PyFCGI log level
 * @param char* fmt the message format
 * @see _vsyslog syslog
 */
#define _syslog(lvl, ...) if(conf->flags & PYFCGI_LOG_FSYSLOG) { \
	syslog(PYFCGI_SYSLOG_LVL(lvl), __VA_ARGS__);\
}
#define _vsyslog(lvl, fmt, ap) if(conf->flags & PYFCGI_LOG_FSYSLOG) { \
	vsyslog(PYFCGI_SYSLOG_LVL(lvl), fmt, ap);\
}

/**@brief Macro checking if syslog is activated and log a message using PyFCGI
 * loglevels
 * @params int lvl the PyFCGI log level
 * @param char* fmt the message format
 * @see vsyslog _syslog
 */


/**@defgroup conf_logger_flags Logger confifurations flags
 * @ingroup conf_logger */
/**@ingroup cong_logger_flags */
#define PYFCGI_LOG_FSYSLOG 1
/**@brief Indicate if the logger should try to reopen on failure
 * @ingroup cong_logger_flags */
#define PYFCGI_LOG_FRETRY 2
/**@brief Exit if failure
 * @ingroup cong_logger_flags */
#define PYFCG_LOG_FEXIT_ONFAIL 4

/**@brief Log level mask
 * @ingroup conf_logger
 * Allow selection of loglevels using a bitwise mask 1 << LEVEL
 */
typedef unsigned char logmask_t;
typedef unsigned char loglvl_t;
typedef struct pyfcgi_logger_s pyfcgi_logger_t;

/**@brief Logger configuration
 * @ingroup conf_logger
 */
struct pyfcgi_conf_logger_s
{
	/**@brief Or combination of @ref PYFCGI_LOG_SYSLOG or
	 * @ref PYFCGI_LOG_RETRY */
	short flags;
	char *syslog_ident;
	int syslog_facility;
	logmask_t syslog_loglvl;
	logmask_t syslog_logtyp;

	/**@brief PyFCGI internal ident, prefixes all log messages */
	char *ident;
	logmask_t facility;

	pyfcgi_logger_t *loggers;
	unsigned char logger_sz;

	char **format;
	unsigned char format_sz;

	/**@brief Internal pipe to tee(2) the message on loggers */
	int pipes[2];
};

/**@brief Informations on a logger
 * @ingroup conf_logger
 */
struct pyfcgi_logger_s
{
	char *filename;
	int fd;
	logmask_t loglvl;
	logmask_t logtyp;

	size_t fmt_id;
};

#include "conf.h"

/**@brief Add a new logger
 * @param char* filename
 * @param logmask_t loglvl a mask indicating wich loglevels should be logged
 * @param logmask_t typemask a mask indicating wich facility should be logged
 * @param char* log format (or NULL for default format)
 */
int pyfcgi_logger_add(const char*, logmask_t, logmask_t, const char*);

/**@brief Add a new format
 * @param char *format
 * @param size_t* idx if not NULL, will contain the format index
 * @return 0 if OK
 */
int pyfcgi_logger_add_format(const char*, size_t*);

/**@brief Open a logger
 * @param pyfcgi_logger_t*
 * @return 0 if no errors
 */
int pyfcgi_logger_open(pyfcgi_logger_t*);

int pyfcgi_logger_set_ident(const char*);

int pyfcgi_log(loglvl_t, const char*, ...);
int vpyfcgi_log(loglvl_t, const char*, va_list);

#endif