path: root/src/log/log.c

/*
    Copyright (C) 2008 Andreas Baumann <abaumann@yahoo.com>

    This program is free software: you can redistribute it and/or modify
    it under the terms of the GNU General Public License as published by
    the Free Software Foundation, either version 3 of the License, or
    (at your option) any later version.

    This program 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 General Public License for more details.

    You should have received a copy of the GNU General Public License
    along with this program.  If not, see <http://www.gnu.org/licenses/>.
*/

#include "log/log.h"

#include "log/messages.h"		/* for i18n */

#include "port/stdio.h"			/* for vsnprintf, snprintf */
#include "port/string.h"		/* for strcmp, strerror_r, strlen,
					   strlcat */
#include "port/time.h"			/* for localtime_r, strftime, time
					 * time_t, struct tm */
#include "port/stdlib.h"		/* for abort, itoa */
#include "port/unused.h"		/* for WOLF_UNUSED */
#define DEFAULT_TEXT_DOMAIN "libwolf"
#include "port/gettext.h"		/* for i18n */

#include <stdarg.h>			/* for variable arguments */
#include <errno.h>			/* for errno */
#include <assert.h>			/* for assertions */

#if defined HAVE_SYSLOG_H
#include <syslog.h>			/* for syslog, closelog and levels */
#endif /* defined HAVE_SYSLOG_H */

#if defined HAVE_EVENTLOG
#define WIN32_MEAN_AND_LEAN
#include <windows.h>
#endif /* defined HAVE_EVENTLOG */

#if defined HAVE_SYSLOG_H
const char *wolf_log_syslog_facility_to_str( wolf_log_syslog_facility_t facility ) {
	switch( facility ) {
		/* Linux, FreeBSD, OpenBSD, NetBSD */
		case WOLF_LOG_KERN:		return "KERN";
		case WOLF_LOG_USER:		return "USER";
		case WOLF_LOG_MAIL:		return "MAIL";
		case WOLF_LOG_DAEMON:		return "DAEMON";
		case WOLF_LOG_AUTH:		return "AUTH";
		case WOLF_LOG_SYSLOG:		return "SYSLOG";
		case WOLF_LOG_LPR:		return "LPR";
		case WOLF_LOG_NEWS:		return "NEWS";
		case WOLF_LOG_UUCP:		return "UUCP";
		case WOLF_LOG_CRON:		return "CRON";
#if defined LOG_AUTHPRIV
		/* Linux, FreeBSD, OpenBSD, NetBSD */
		case WOLF_LOG_AUTHPRIV:		return "AUTHPRIV";
#else
		case WOLF_LOG_AUTHPRIV:		return "<unknown>";
#endif
#if defined LOG_FTP
		/* Linux, FreeBSD, OpenBSD, NetBSD */
		case WOLF_LOG_FTP:		return "FTP";
#else
		case WOLF_LOG_FTP:		return "<unknown>";
#endif
#if defined LOG_NTP
		/* FreeBSD */
		case WOLF_LOG_NTP:		return "NTP";
#else
		case WOLF_LOG_NTP:		return "<unknown>";
#endif
#if defined LOG_SECURITY
		/* FreeBSD */
		case WOLF_LOG_SECURITY:		return "SECURITY";
#else
		case WOLF_LOG_SECURITY:		return "<unknown>";
#endif
#if defined LOG_CONSOLE
		/* FreeBSD */
		case WOLF_LOG_CONSOLE:		return "CONSOLE";
#else
		case WOLF_LOG_CONSOLE:		return "<unknown>";
#endif
#if defined LOG_AUDIT
		/* Solaris 10 */
		case WOLF_LOG_AUDIT:		return "AUDIT";
#else
		case WOLF_LOG_AUDIT:		return "<unknown>";
#endif
		case WOLF_LOG_LOCAL0:		return "LOCAL0";
		case WOLF_LOG_LOCAL1:		return "LOCAL1";
		case WOLF_LOG_LOCAL2:		return "LOCAL2";
		case WOLF_LOG_LOCAL3:		return "LOCAL3";
		case WOLF_LOG_LOCAL4:		return "LOCAL4";
		case WOLF_LOG_LOCAL5:		return "LOCAL5";
		case WOLF_LOG_LOCAL6:		return "LOCAL6";
		case WOLF_LOG_LOCAL7:		return "LOCAL7";
		default:			return "<unknown>";
	}
}
#endif /* defined HAVE_SYSLOG_H */

#if defined HAVE_SYSLOG_H
wolf_log_syslog_facility_t wolf_log_str_to_syslog_facility( const char *facility ) {
	if( strcmp( facility, "KERN" ) == 0 )		return WOLF_LOG_KERN;
	if( strcmp( facility, "USER" ) == 0 )		return WOLF_LOG_USER;
	if( strcmp( facility, "MAIL" ) == 0 )		return WOLF_LOG_MAIL;
	if( strcmp( facility, "DAEMON" ) == 0 )		return WOLF_LOG_DAEMON;
	if( strcmp( facility, "AUTH" ) == 0 )		return WOLF_LOG_AUTH;
	if( strcmp( facility, "SYSLOG" ) == 0 )		return WOLF_LOG_SYSLOG;
	if( strcmp( facility, "LPR" ) == 0 )		return WOLF_LOG_LPR;
	if( strcmp( facility, "NEWS" ) == 0 )		return WOLF_LOG_NEWS;
	if( strcmp( facility, "UUCP" ) == 0 )		return WOLF_LOG_UUCP;
	if( strcmp( facility, "CRON" ) == 0 )		return WOLF_LOG_CRON;
	if( strcmp( facility, "AUTHPRIV" ) == 0 )	return WOLF_LOG_AUTHPRIV;
	if( strcmp( facility, "FTP" ) == 0 )		return WOLF_LOG_FTP;
	if( strcmp( facility, "NTP" ) == 0 )		return WOLF_LOG_NTP;
	if( strcmp( facility, "SECURITY" ) == 0 )	return WOLF_LOG_SECURITY;
	if( strcmp( facility, "CONSOLE" ) == 0 )	return WOLF_LOG_CONSOLE;
	if( strcmp( facility, "AUDIT" ) == 0 )		return WOLF_LOG_AUDIT;
	if( strcmp( facility, "LOCAL0" ) == 0 )		return WOLF_LOG_LOCAL0;
	if( strcmp( facility, "LOCAL1" ) == 0 )		return WOLF_LOG_LOCAL1;
	if( strcmp( facility, "LOCAL2" ) == 0 )		return WOLF_LOG_LOCAL2;
	if( strcmp( facility, "LOCAL3" ) == 0 )		return WOLF_LOG_LOCAL3;
	if( strcmp( facility, "LOCAL4" ) == 0 )		return WOLF_LOG_LOCAL4;
	if( strcmp( facility, "LOCAL5" ) == 0 )		return WOLF_LOG_LOCAL5;
	if( strcmp( facility, "LOCAL6" ) == 0 )		return WOLF_LOG_LOCAL6;
	if( strcmp( facility, "LOCAL7" ) == 0 )		return WOLF_LOG_LOCAL7;

	/* this is a seasonable default if nothing else exists */
	return WOLF_LOG_DAEMON;
}
#endif /* defined HAVE_SYSLOG_H */

#if defined HAVE_SYSLOG_H
bool wolf_log_platform_has_syslog_facility( wolf_log_syslog_facility_t facility ) {
	switch( facility ) {
		/* Linux, FreeBSD, OpenBSD, NetBSD */
		case WOLF_LOG_KERN:
		case WOLF_LOG_USER:
		case WOLF_LOG_MAIL:
		case WOLF_LOG_DAEMON:
		case WOLF_LOG_AUTH:
		case WOLF_LOG_SYSLOG:
		case WOLF_LOG_LPR:
		case WOLF_LOG_NEWS:
		case WOLF_LOG_UUCP:
		case WOLF_LOG_CRON:
		case WOLF_LOG_LOCAL0:
		case WOLF_LOG_LOCAL1:
		case WOLF_LOG_LOCAL2:
		case WOLF_LOG_LOCAL3:
		case WOLF_LOG_LOCAL4:
		case WOLF_LOG_LOCAL5:
		case WOLF_LOG_LOCAL6:
		case WOLF_LOG_LOCAL7:
						return true;
#if defined LOG_AUTHPRIV
		/* Linux, FreeBSD, OpenBSD, NetBSD */
		case WOLF_LOG_AUTHPRIV:		return true;
#else
		case WOLF_LOG_AUTHPRIV:		return false;
#endif
#if defined LOG_FTP
		/* Linux, FreeBSD, OpenBSD, NetBSD */
		case WOLF_LOG_FTP:		return true;
#else
		case WOLF_LOG_FTP:		return false;
#endif
#if defined LOG_NTP
		/* FreeBSD */
		case WOLF_LOG_NTP:		return true;
#else
		case WOLF_LOG_NTP:		return false;
#endif
#if defined LOG_SECURITY
		/* FreeBSD */
		case WOLF_LOG_SECURITY:		return true;
#else
		case WOLF_LOG_SECURITY:		return false;
#endif
#if defined LOG_CONSOLE
		/* FreeBSD */
		case WOLF_LOG_CONSOLE:		return true;
#else
		case WOLF_LOG_CONSOLE:		return false;
#endif
#if defined LOG_AUDIT
		/* Solaris 10 */
		case WOLF_LOG_AUDIT:		return true;
#else
		case WOLF_LOG_AUDIT:		return false;
#endif
	}

	return false;
}
#endif /* defined HAVE_SYSLOG_H */

wolf_log_level_t wolf_log_str_to_level( const char *level ) {
	if( strcmp( level, "EMERG" ) == 0 )   return WOLF_LOG_EMERG;
	if( strcmp( level, "ALERT" ) == 0 )   return WOLF_LOG_ALERT;
	if( strcmp( level, "CRIT" ) == 0 )    return WOLF_LOG_CRIT;
	if( strcmp( level, "ERR" ) == 0 )     return WOLF_LOG_ERR;
	if( strcmp( level, "WARNING" ) == 0 ) return WOLF_LOG_WARNING;
	if( strcmp( level, "NOTICE" ) == 0 )  return WOLF_LOG_NOTICE;
	if( strcmp( level, "INFO" ) == 0 )    return WOLF_LOG_INFO;
	if( strcmp( level, "DEBUG" ) == 0 )   return WOLF_LOG_DEBUG;
	if( strcmp( level, "DEBUG1" ) == 0 )  return WOLF_LOG_DEBUG1;
	if( strcmp( level, "DEBUG2" ) == 0 )  return WOLF_LOG_DEBUG2;
	if( strcmp( level, "DEBUG3" ) == 0 )  return WOLF_LOG_DEBUG3;
	if( strcmp( level, "DEBUG4" ) == 0 )  return WOLF_LOG_DEBUG4;
	if( strcmp( level, "DEBUG5" ) == 0 )  return WOLF_LOG_DEBUG5;

	return WOLF_LOG_EMERG;
}

#if defined HAVE_SYSLOG_H
static int map_log_to_syslog_level( wolf_log_level_t level ) {
	switch( level ) {
		case WOLF_LOG_EMERG:		return LOG_EMERG;
		case WOLF_LOG_ALERT:		return LOG_ALERT;
		case WOLF_LOG_CRIT:		return LOG_CRIT;
		case WOLF_LOG_ERR:		return LOG_ERR;
		case WOLF_LOG_WARNING:		return LOG_WARNING;
		case WOLF_LOG_NOTICE:		return LOG_NOTICE;
		case WOLF_LOG_INFO:		return LOG_INFO;
		case WOLF_LOG_DEBUG:
		case WOLF_LOG_DEBUG1:
		case WOLF_LOG_DEBUG2:
		case WOLF_LOG_DEBUG3:
		case WOLF_LOG_DEBUG4:
		case WOLF_LOG_DEBUG5:		return LOG_DEBUG;
		default:			return LOG_EMERG;
	}
}
#endif /* defined HAVE_SYSLOG_H */

#if defined HAVE_EVENTLOG
/* TODO: logging of audit success/fail and how to map this to the
 * upper layer (so on Unix things can also go to LOG_SECURITY or
 * LOG_AUDIT on special Unixes. But for this we have to read a
 * log first!
 */
static WORD wolf_log_level_to_eventlog_type(  wolf_log_level_t level ) {
	switch( level ) {
		case WOLF_LOG_EMERG:
		case WOLF_LOG_ALERT:
		case WOLF_LOG_CRIT:
		case WOLF_LOG_ERR:		return EVENTLOG_ERROR_TYPE;
		case WOLF_LOG_WARNING:		return EVENTLOG_WARNING_TYPE;
		case WOLF_LOG_NOTICE:
		case WOLF_LOG_INFO:
		case WOLF_LOG_DEBUG:
		case WOLF_LOG_DEBUG1:
		case WOLF_LOG_DEBUG2:
		case WOLF_LOG_DEBUG3:
		case WOLF_LOG_DEBUG4:
		case WOLF_LOG_DEBUG5:		return EVENTLOG_INFORMATION_TYPE;
		default:			return -1;
	}
}

/*
   Values are 32 bit values layed out as follows:
 
    3 3 2 2 2 2 2 2 2 2 2 2 1 1 1 1 1 1 1 1 1 1
    1 0 9 8 7 6 5 4 3 2 1 0 9 8 7 6 5 4 3 2 1 0 9 8 7 6 5 4 3 2 1 0
   +---+-+-+-----------------------+-------------------------------+
   |Sev|C|R|     Facility          |               Code            |
   +---+-+-+-----------------------+-------------------------------+
 
    1 1 0 0

   where
 
       Sev - is the severity code
 
           00 - Success
           01 - Informational
           10 - Warning
           11 - Error
 
       C - is the Customer code flag
 
       R - is a reserved bit
 
       Facility - is the facility code
 
       Code - is the facility's status code
 
   Define the facility codes

SeverityNames = ( 
	Success		= 0x0	: STATUS_SEVERITY_SUCCESS
	Informational	= 0x1	: STATUS_SEVERITY_INFORMATIONAL
	Warning		= 0x2	: STATUS_SEVERITY_WARNING
	Error		= 0x4	: STATUS_SEVERITY_ERROR
)

;we get a already defined message? but where is Application defined?
;// facility names
;FacilityNames = (
;	System		= 0x0FF
;	Application	= 0xFFF
;)

*/

static DWORD wolf_log_category_to_eventlog_category( int category_id ) {
	return( category_id | 0x0FFF0000L );
}

static DWORD wolf_log_event_id_to_eventlog_event_id( WORD severity, int message_id ) {
	DWORD id;

	/* no clue, why the bitmask has to differ from the EVENTLOG_xxx
	 * constants, but so it is..
	 *
	 * 00 - Success			0
	 * 01 - Informational		4
	 * 10 - Warning			2
	 * 11 - Error			1
	 */
	int s = 0;
	switch( severity ) {
		case EVENTLOG_ERROR_TYPE:	s = 3; break;
		case EVENTLOG_WARNING_TYPE:	s = 2; break;
		case EVENTLOG_INFORMATION_TYPE:	s = 1; break;
	}

	return( message_id | 0x0FFF0000L | ( s << 30 ) );
}

#endif /* defined HAVE_EVENTLOG */

#if defined HAVE_SYSLOG_H
static int map_log_facility_to_syslog_facility( int facility ) {
	switch( facility ) {
		case WOLF_LOG_KERN:		return LOG_KERN;
		case WOLF_LOG_USER:		return LOG_USER;
		case WOLF_LOG_MAIL:		return LOG_MAIL;
		case WOLF_LOG_DAEMON:		return LOG_DAEMON;
		case WOLF_LOG_AUTH:		return LOG_AUTH;
		case WOLF_LOG_SYSLOG:		return LOG_SYSLOG;
		case WOLF_LOG_LPR:		return LOG_LPR;
		case WOLF_LOG_NEWS:		return LOG_NEWS;
		case WOLF_LOG_UUCP:		return LOG_UUCP;
		case WOLF_LOG_CRON:		return LOG_CRON;
#if defined LOG_AUTHPRIV
		case WOLF_LOG_AUTHPRIV:		return LOG_AUTHPRIV;
#else
		case WOLF_LOG_AUTHPRIV:		return LOG_DAEMON;
#endif
#if defined LOG_FTP
		case WOLF_LOG_FTP:		return LOG_FTP;
#else
		case WOLF_LOG_FTP:		return LOG_DAEMON;
#endif
#if defined LOG_NTP
		case WOLF_LOG_NTP:		return LOG_NTP;
#else
		case WOLF_LOG_NTP:		return LOG_DAEMON;
#endif
#if defined LOG_SECURITY
		case WOLF_LOG_SECURITY:		return LOG_SECURITY;
#else
		case WOLF_LOG_SECURITY:		return LOG_DAEMON;
#endif
#if defined LOG_CONSOLE
		case WOLF_LOG_CONSOLE:		return LOG_CONSOLE;
#else
		case WOLF_LOG_CONSOLE:		return LOG_DAEMON;
#endif
#if defined LOG_AUDIT
		case WOLF_LOG_AUDIT:		return LOG_AUDIT;
#else
		case WOLF_LOG_AUDIT:		return LOG_DAEMON;
#endif
		case WOLF_LOG_LOCAL0:		return LOG_LOCAL0;
		case WOLF_LOG_LOCAL1:		return LOG_LOCAL1;
		case WOLF_LOG_LOCAL2:		return LOG_LOCAL2;
		case WOLF_LOG_LOCAL3:		return LOG_LOCAL3;
		case WOLF_LOG_LOCAL4:		return LOG_LOCAL4;
		case WOLF_LOG_LOCAL5:		return LOG_LOCAL5;
		case WOLF_LOG_LOCAL6:		return LOG_LOCAL6;
		case WOLF_LOG_LOCAL7:		return LOG_LOCAL7;
		default:		return LOG_DAEMON;
	}
}
#endif /* defined HAVE_SYSLOG_H */

const char *wolf_log_level_to_str( wolf_log_level_t level ) {
	switch( level ) {
		case WOLF_LOG_EMERG:	return "EMERG";
		case WOLF_LOG_ALERT:	return "ALERT";
		case WOLF_LOG_CRIT:	return "CRIT";
		case WOLF_LOG_ERR:	return "ERR";
		case WOLF_LOG_WARNING:	return "WARNING";
		case WOLF_LOG_NOTICE:	return "NOTICE";
		case WOLF_LOG_INFO:	return "INFO";
		case WOLF_LOG_DEBUG:	return "DEBUG";
		case WOLF_LOG_DEBUG1:	return "DEBUG1";
		case WOLF_LOG_DEBUG2:	return "DEBUG2";
		case WOLF_LOG_DEBUG3:	return "DEBUG3";
		case WOLF_LOG_DEBUG4:	return "DEBUG4";
		case WOLF_LOG_DEBUG5:	return "DEBUG5";
		default:		return "<unknown>";
	}
}

static const char *log_logfile_filename;
static FILE *log_file = NULL;
static wolf_log_level_t log_logfile_level;
static wolf_log_level_t log_stderr_level;
#if defined HAVE_SYSLOG_H
static const char *syslog_ident;
static int syslog_facility;
static int syslog_level;
static int syslog_options;
#endif /* defined HAVE_SYSLOG_H */
#if defined HAVE_EVENTLOG
static HANDLE event_source = 0;
static int eventlog_level;
static const char *eventlog_server;
static const char *eventlog_log;
static const char *eventlog_source;
static PSID sid = NULL;
#endif /* defined HAVE_EVENTLOG */

void wolf_log_openlogtofile( const char *filename, wolf_log_level_t level ) {
	log_logfile_filename = filename;
	log_logfile_level = level;
	wolf_log_reopenlogtofile( );
}

#if defined HAVE_SYSLOG_H
static int map_log_options_to_syslog_options( int opts ) {
	int syslog_opts = LOG_NDELAY;

	if( ( opts & WOLF_LOG_SYSLOG_PID ) == WOLF_LOG_SYSLOG_PID ) {
		syslog_opts |= LOG_PID;
	}
	if( ( opts & WOLF_LOG_SYSLOG_CONS ) == WOLF_LOG_SYSLOG_CONS ) {
		syslog_opts |= LOG_CONS;
	}

	return syslog_opts;
}
#endif /* defined HAVE_SYSLOG_H */

#if defined HAVE_SYSLOG_H
void wolf_log_openlogtosyslog(	const char *ident,
				wolf_log_syslog_facility_t facility,
				wolf_log_level_t level,
				int options ) {
	syslog_ident = ident;
	syslog_facility = map_log_facility_to_syslog_facility( facility );
	syslog_level = map_log_to_syslog_level( level );
	syslog_options = map_log_options_to_syslog_options( options );

	openlog( ident, LOG_CONS | LOG_NDELAY, facility );
	setlogmask( LOG_UPTO( level ) );
}
#endif /* defined HAVE_SYSLOG_H */

#if defined HAVE_EVENTLOG

static void registry_set_expandable_string( HKEY h, TCHAR *name, TCHAR *value ) {
	RegSetValueEx( h, name, 0, REG_EXPAND_SZ, (LPBYTE)value, strlen( value ) );
}

static void registry_set_word( HKEY h, TCHAR *name, DWORD value ) {
	RegSetValueEx( h, name, 0, REG_DWORD, (LPBYTE)&value, sizeof( DWORD ) );
}

static void register_event_source( const char *log, const char *source, const char *path_to_dll, int nof_categories ) {
	char key[256];
	HKEY h = 0;
	DWORD disposition;

	/* compose the registry key and simply overwrite the values there, we know */
	snprintf( key, 256, "SYSTEM\\CurrentControlSet\\Services\\EventLog\\%s\\%s", log, source );
	RegCreateKeyEx( HKEY_LOCAL_MACHINE, key, 0, NULL, REG_OPTION_NON_VOLATILE,
		KEY_SET_VALUE, NULL, &h, &disposition );

	/* make sure not to have hard-coded pathes here, otherwise remote
	 * event logging will not work! */
	registry_set_expandable_string( h, "EventMessageFile", (char *)path_to_dll );
	registry_set_expandable_string( h, "CategoryMessageFile", (char *)path_to_dll );
	registry_set_word( h, "TypesSupported", (DWORD)7 );
	registry_set_word( h, "CategoryCount", (DWORD)nof_categories );
	RegCloseKey( h );
}

static PSID get_current_sid( void ) {
	HANDLE process = NULL;
	HANDLE token = NULL;
	DWORD token_user_size = 0;
	PTOKEN_USER token_user;
	PSID token_sid = NULL;
	DWORD sid_size = 0;
	PSID sid = NULL;

	/* get the token for the current process */
	process = GetCurrentProcess( );
	if( process == NULL ) {
		fprintf( stderr, "%s: Unable to get current process handle\n",
			wolf_log_level_to_str( WOLF_LOG_ALERT ) );
		abort( );
	}
	if( !OpenProcessToken( process, TOKEN_QUERY, &token ) ) {
		fprintf( stderr, "%s: Unable to get process token of current process\n",
			wolf_log_level_to_str( WOLF_LOG_ALERT ) );
		abort( );
	}

	/* get the required size to store the user token and allocate memory for it */
	(void)GetTokenInformation( token, TokenUser, NULL, 0, &token_user_size );
	token_user = (PTOKEN_USER)malloc( token_user_size * sizeof( BYTE ) );
	if( token_user == NULL ) {
		fprintf( stderr, "%s: Unable to get memory to store user token\n",
			wolf_log_level_to_str( WOLF_LOG_ALERT ) );
		CloseHandle( token );
		abort( );
	}

	/* get the user token */
	if( !GetTokenInformation( token, TokenUser, (LPVOID)token_user, token_user_size, &token_user_size ) ) {
		fprintf( stderr, "%s: Unable to get user token\n",
			wolf_log_level_to_str( WOLF_LOG_ALERT ) );
		free( token_user );
		CloseHandle( token );
		abort( );
	}

	/* finally we made our way to the SID. Make a local copy of it because it and return that one */
	token_sid = (PSID)token_user->User.Sid;
	sid_size = GetLengthSid( token_sid );
	sid = (PSID)malloc( sid_size );
	if( sid != NULL ) {
		if( !CopySid( sid_size, sid, token_sid ) ) {
			fprintf( stderr, "%s: Unable to make a copy of the current SID\n",
				wolf_log_level_to_str( WOLF_LOG_ALERT ) );
			free( sid );
			free( token_user );
			CloseHandle( token );
			abort( );
		}
	}

	/* process handle is a pseudo handle which doesn't need closing */
	free( token_user );
	CloseHandle( token );

	return sid;
}

/* FIXME: those two functions are really bad and must be fixed together
 * with a POSIX-positional C-sprintf. For now we should be careful that
 * we log simple things..
 */

static int compute_nof_placeholders( 		const char *format ) {
	const char *c;
	int nof_placeholders;

	for( c = format, nof_placeholders = 0; *c != '\0'; c++ )
		if( *c == '%' && *(c+1) != '%' )
			nof_placeholders++;

	return nof_placeholders;
}

static void map_placeholders_to_strings( 	char **msg_arr,
						const char *format,
						va_list ap ) {
	const char *c;
	int field;
	int i;
	int size;
	char *s;

	for( c = format, field = 0; *c != '\0'; c++ ) {
		if( *c == '%' && *(c+1) != '%' ) {
			switch( *(c+1) ) {
				case 'd':
					i = va_arg( ap, int );
					msg_arr[field] = (char *)malloc( 20 );
					snprintf( msg_arr[field], 20, "%d", i );
					field++;
					break;

				case 's':
					s = va_arg( ap, char * );
					msg_arr[field] = (char *)malloc( 512 );
					snprintf( msg_arr[field], 512, "%s", s );
					field++;
					break;
			}
			c++;
		}
	}
}

void wolf_log_openlogtoeventlog(	const char *server,
					const char *log,
					const char *source,
					const char *path_to_dll,
					int nof_categories,
					wolf_log_level_t level ) {
	eventlog_server = server;
	eventlog_log = log;
	eventlog_source = source;
	eventlog_level = level;

	/* fiddle in the registry and register the location of the
	 * message DLL, how many categories we define and what types
	 * of events we are supporting
	 */
	register_event_source( log, source, path_to_dll, nof_categories );

	/* for logging the user of the process into the event log */	
	sid = get_current_sid( );

	/* TODO: remote machine and event log source should be in the API,
	 * but we have Windows localized strings which are hard to unify
	 * with Unix. We also don't want to have a stupid string wrapper
	 * on top.. No clue for now
	 */
        event_source = RegisterEventSource( server, source );
	if( event_source == NULL ) {
		/* TODO: add GetLastError here! */
		fprintf( stderr, "%s: Unable to register event source\n",
			wolf_log_level_to_str( WOLF_LOG_ALERT ) );
	}
}
#endif /* defined HAVE_EVENTLOG */

void wolf_log_openlogtostderr( wolf_log_level_t level ) {
	log_stderr_level = level;
}

void wolf_log_closelogtofile( void ) {
	if( log_file != NULL ) {
		fclose( log_file );
		log_file = NULL;
	}
}

#if defined HAVE_SYSLOG_H
void wolf_log_closelogtosyslog( void ) {
	closelog( );
}
#endif /* defined HAVE_SYSLOG_H */

#if defined HAVE_EVENTLOG
void wolf_log_closelogtoeventlog( void ) {
	if( sid != NULL ) {
		free( sid );
		sid = NULL;
	}

	if( !DeregisterEventSource( event_source ) ) {
		/* TODO: add GetLastError here! */
		fprintf( stderr, "%s: Unable to deregister event source handle\n",
			wolf_log_level_to_str( WOLF_LOG_ALERT ) );
	}
}
#endif /* defined HAVE_EVENTLOG */

void wolf_log_closelogtostderr( void ) {
	/* do nothing here */
}

void wolf_log_reopenlogtofile( void ) {
	if( log_file != NULL ) {
		fclose( log_file );
	}
	log_file = fopen( log_logfile_filename, "a" );
	if( log_file == NULL ) {
		char errmsg[255];
		strerror_r( errno, errmsg, 255 );
		fprintf( stderr, "%s: Unable to open logfile '%s': %s\n",
			wolf_log_level_to_str( WOLF_LOG_ALERT ),
			log_logfile_filename, errmsg );
	}
}

#if defined HAVE_SYSLOG_H
void wolf_log_reopenlogtosyslog( void ) {
	openlog( syslog_ident, syslog_options, syslog_facility );
	setlogmask( LOG_UPTO( syslog_level ) );
}
#endif /* defined HAVE_SYSLOG_H */

#if defined HAVE_EVENTLOG
void wolf_log_reopenlogtoeventlog( void ) {
	/* TODO: close and open? */
}
#endif /* defined HAVE_EVENTLOG */

static void wolf_log_ap( wolf_log_level_t level, int category_id, int message_id, const char *format, va_list ap );

void wolf_log( wolf_log_level_t level, int category_id, int message_id, const char *format, ... ) {
	va_list ap;

	va_start( ap, format );
	wolf_log_ap( level, category_id, message_id, format, ap );
	va_end( ap );
}

static void wolf_log_ap( wolf_log_level_t level, int category_id, int message_id, const char *format, va_list ap ) {
	char s[1024];

	vsnprintf( s, 1024, format, ap );

	if( level <= log_stderr_level )
		fprintf( stderr, "%s: %s\n",wolf_log_level_to_str( level ), s );
	
	if( level <= log_logfile_level && log_file != NULL ) {
		time_t t;
		struct tm local_time;
		char date_str[100];

		time( &t );
		assert( t >= 0 ); /* actually the only error known is an illegal buffer */
		if( localtime_r( &t, &local_time ) == NULL ) {
			char errmsg[512];
			strerror_r( errno, errmsg, 512 );
			fprintf( stderr, _( "%s: localtime_r failed: %s\n" ),
				 wolf_log_level_to_str( WOLF_LOG_ALERT ), errmsg );
			abort( );
		}
		
		strftime( date_str, 100, "%b %d %H:%M:%S", &local_time );

		fprintf( log_file, "%s %s %d-%d: %s\n",
			date_str, wolf_log_level_to_str( level ), category_id, message_id, s );
		fflush( log_file );
	}

#if defined HAVE_SYSLOG_H
	syslog( map_log_to_syslog_level( level ), "%s", s );
#endif /* defined HAVE_SYSLOG_H */

#if defined HAVE_EVENTLOG
	if( level <= eventlog_level && event_source != 0 ) {
		/* parse C-snprintf-like format string, map the placeholders
		 * there to normal strings, then add them to a string array
		 */
		int nof_placeholders = compute_nof_placeholders( format );
		LPSTR *msg_arr = (LPSTR *)malloc( sizeof( LPCTSTR ) * nof_placeholders );

		map_placeholders_to_strings( msg_arr, format, ap );

		if( !ReportEvent(
			event_source,	/* event source handle */
			wolf_log_level_to_eventlog_type( level ),
			wolf_log_category_to_eventlog_category( category_id ),
			wolf_log_event_id_to_eventlog_event_id( 
				wolf_log_level_to_eventlog_type( level ),
				message_id ),
			sid,			/* the security identifier */
			nof_placeholders,	/* at the moment only one string */
			0,			/* no binary raw data */
			msg_arr,		/* the array of strings */
			NULL 			/* no binary raw data */
			) ) {
			/* TODO: add GetLastError here! */
			fprintf( stderr, "%s: Unable to log to event log\n",
				wolf_log_level_to_str( WOLF_LOG_ALERT ) );
		}

		free( (LPSTR *)msg_arr );
	}
#endif /* defined HAVE_EVENTLOG */
}