/*
 * Copyright 2003,2004 The Apache Software Foundation.
 * 
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 * 
 *      http://www.apache.org/licenses/LICENSE-2.0
 * 
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
 
#include <log4cxx/net/syslogappender.h>
#include <log4cxx/helpers/loglog.h>
#include <log4cxx/helpers/stringhelper.h>
#include <log4cxx/helpers/datagramsocket.h>
#include <log4cxx/spi/loggingevent.h>
#include <log4cxx/level.h>

#ifdef HAVE_SYSLOG
	#include <syslog.h>	
#else
	/* facility codes */
	#define	LOG_KERN	(0<<3)	/* kernel messages */
	#define	LOG_USER	(1<<3)	/* random user-level messages */
	#define	LOG_MAIL	(2<<3)	/* mail system */
	#define	LOG_DAEMON	(3<<3)	/* system daemons */
	#define	LOG_AUTH	(4<<3)	/* security/authorization messages */
	#define	LOG_SYSLOG	(5<<3)	/* messages generated internally by syslogd */
	#define	LOG_LPR		(6<<3)	/* line printer subsystem */
	#define	LOG_NEWS	(7<<3)	/* network news subsystem */
	#define	LOG_UUCP	(8<<3)	/* UUCP subsystem */
	#define	LOG_CRON	(9<<3)	/* clock daemon */
	#define	LOG_AUTHPRIV	(10<<3)	/* security/authorization messages (private) */
	#define	LOG_FTP		(11<<3)	/* ftp daemon */
	
		/* other codes through 15 reserved for system use */
	#define	LOG_LOCAL0	(16<<3)	/* reserved for local use */
	#define	LOG_LOCAL1	(17<<3)	/* reserved for local use */
	#define	LOG_LOCAL2	(18<<3)	/* reserved for local use */
	#define	LOG_LOCAL3	(19<<3)	/* reserved for local use */
	#define	LOG_LOCAL4	(20<<3)	/* reserved for local use */
	#define	LOG_LOCAL5	(21<<3)	/* reserved for local use */
	#define	LOG_LOCAL6	(22<<3)	/* reserved for local use */
	#define	LOG_LOCAL7	(23<<3)	/* reserved for local use */
#endif

#define LOG_UNDEF -1

using namespace log4cxx;
using namespace log4cxx::helpers;
using namespace log4cxx::net;

IMPLEMENT_LOG4CXX_OBJECT(SyslogAppender)

SyslogAppender::SyslogAppender()
: syslogFacility(LOG_USER), facilityPrinting(false), sw(0)
{
	this->initSyslogFacilityStr();

}

SyslogAppender::SyslogAppender(const LayoutPtr& layout,
	int syslogFacility)
: syslogFacility(syslogFacility), facilityPrinting(false), sw(0)
{
	this->layout = layout;
	this->initSyslogFacilityStr();
}

SyslogAppender::SyslogAppender(const LayoutPtr& layout,
	const String& syslogHost, int syslogFacility)
: syslogFacility(syslogFacility), facilityPrinting(false), sw(0)
{
	this->layout = layout;
	this->initSyslogFacilityStr();
	setSyslogHost(syslogHost);
}

SyslogAppender::~SyslogAppender()
{
	finalize();
}

/** Release any resources held by this SyslogAppender.*/
void SyslogAppender::close()
{
	closed = true;
	if (sw != 0)
	{
		delete sw;
		sw = 0;
	}
}

void SyslogAppender::initSyslogFacilityStr()
{
	facilityStr = getFacilityString(this->syslogFacility);

	if (facilityStr.empty())
	{
		LOGLOG_ERROR(_T("\"") << syslogFacility <<
					_T("\" is an unknown syslog facility. Defaulting to \"USER\"."));
		this->syslogFacility = LOG_USER;
		facilityStr = _T("user:");
	}
	else
	{
		facilityStr += _T(":");
	}
}

/**
Returns the specified syslog facility as a lower-case String,
e.g. "kern", "user", etc.
*/
String SyslogAppender::getFacilityString(
	int syslogFacility)
{
	switch(syslogFacility)
	{
	case LOG_KERN:      return _T("kern");
	case LOG_USER:      return _T("user");
	case LOG_MAIL:      return _T("mail");
	case LOG_DAEMON:    return _T("daemon");
	case LOG_AUTH:      return _T("auth");
	case LOG_SYSLOG:    return _T("syslog");
	case LOG_LPR:       return _T("lpr");
	case LOG_NEWS:      return _T("news");
	case LOG_UUCP:      return _T("uucp");
	case LOG_CRON:      return _T("cron");
#ifdef LOG_AUTHPRIV
	case LOG_AUTHPRIV:  return _T("authpriv");
#endif
#ifdef LOG_FTP
	case LOG_FTP:       return _T("ftp");
#endif
	case LOG_LOCAL0:    return _T("local0");
	case LOG_LOCAL1:    return _T("local1");
	case LOG_LOCAL2:    return _T("local2");
	case LOG_LOCAL3:    return _T("local3");
	case LOG_LOCAL4:    return _T("local4");
	case LOG_LOCAL5:    return _T("local5");
	case LOG_LOCAL6:    return _T("local6");
	case LOG_LOCAL7:    return _T("local7");
	default:            return String();
	}
}

int SyslogAppender::getFacility(
	const String &facilityName)
{
	String s = StringHelper::toUpperCase(StringHelper::trim(facilityName));

	if (s == _T("KERN"))
	{
		return LOG_KERN;
	}
	else if (s == _T("USER"))
	{
		return LOG_USER;
	}
	else if (s == _T("MAIL"))
	{
		return LOG_MAIL;
	}
	else if (s == _T("DAEMON"))
	{
		return LOG_DAEMON;
	}
	else if (s == _T("AUTH"))
	{
		return LOG_AUTH;
	}
	else if (s == _T("SYSLOG"))
	{
		return LOG_SYSLOG;
	}
	else if (s == _T("LPR"))
	{
		return LOG_LPR;
	}
	else if (s == _T("NEWS"))
	{
		return LOG_NEWS;
	}
	else if (s == _T("UUCP"))
	{
		return LOG_UUCP;
	}
	else if (s == _T("CRON"))
	{
		return LOG_CRON;
	}
#ifdef LOG_AUTHPRIV
	else if (s == _T("AUTHPRIV"))
	{
		return LOG_AUTHPRIV;
	}
#endif
#ifdef LOG_FTP
	else if (s == _T("FTP"))
	{
		return LOG_FTP;
	}
#endif
	else if (s == _T("LOCAL0"))
	{
		return LOG_LOCAL0;
	}
	else if (s == _T("LOCAL1"))
	{
		return LOG_LOCAL1;
	}
	else if (s == _T("LOCAL2"))
	{
		return LOG_LOCAL2;
	}
	else if (s == _T("LOCAL3"))
	{
		return LOG_LOCAL3;
	}
	else if (s == _T("LOCAL4"))
	{
		return LOG_LOCAL4;
	}
	else if (s == _T("LOCAL5"))
	{
		return LOG_LOCAL5;
	}
	else if (s == _T("LOCAL6"))
	{
		return LOG_LOCAL6;
	}
	else if (s == _T("LOCAL7"))
	{
		return LOG_LOCAL7;
	}
	else
	{
		return LOG_UNDEF;
	}
}

void SyslogAppender::append(const spi::LoggingEventPtr& event)
{
	if	(!isAsSevereAsThreshold(event->getLevel()))
		return;

// On the local host, we can directly use the system function 'syslog'
// if it is available
#ifdef HAVE_SYSLOG	
	if (sw == 0)
	{
  		StringBuffer sbuf;
 		layout->format(sbuf, event);
		USES_CONVERSION;
		
		// use of "%s" to avoid a security hole
        ::syslog(syslogFacility | event->getLevel()->getSyslogEquivalent(), 
			"%s", T2A(sbuf.str().c_str()));
			
		return;
	}
#endif

	// We must not attempt to append if sw is null.
	if(sw == 0)
	{
		errorHandler->error(_T("No syslog host is set for SyslogAppedender named \"")+
			this->name+_T("\"."));
		return;
	}

	StringBuffer sbuf;

	sbuf << _T("<") << (syslogFacility | event->getLevel()->getSyslogEquivalent()) << _T(">");
	if (facilityPrinting)
	{
		sbuf << facilityStr;
	}
	layout->format(sbuf, event);
	//LogLog::debug(sbuf.str());
	sw->write(sbuf.str());
}

void SyslogAppender::activateOptions()
{
}

void SyslogAppender::setOption(const String& option, const String& value)
{
	if (StringHelper::equalsIgnoreCase(option, _T("sysloghost")))
	{
		setSyslogHost(value);
	}
	else if (StringHelper::equalsIgnoreCase(option, _T("facility")))
	{
		setFacility(value);
	}
	else
	{
		AppenderSkeleton::setOption(name, value);
	}
}

void SyslogAppender::setSyslogHost(const String& syslogHost)
{
	if (this->sw != 0)
	{
		delete this->sw;
		this->sw = 0;
	}
	
// On the local host, we can directly use the system function 'syslog'
// if it is available (cf. append)
#ifdef HAVE_SYSLOG	
	if (syslogHost != _T("localhost") && syslogHost != _T("127.0.0.1")
	&& !syslogHost.empty())
#endif		
		this->sw = new SyslogWriter(syslogHost);
		
	this->syslogHost = syslogHost;
}


void SyslogAppender::setFacility(const String& facilityName)
{
	if (facilityName.empty())
	{
		return;
	}

	syslogFacility = getFacility(facilityName);
	if (syslogFacility == LOG_UNDEF)
	{
		LogLog::error(_T("[")+facilityName +
				_T("] is an unknown syslog facility. Defaulting to [USER]."));
		syslogFacility = LOG_USER;
	}

	this->initSyslogFacilityStr();
}