/** @file log.cpp
 */

/*    Copyright 2009 10gen Inc.
 *
 *    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 "pch.h"
#include "assert_util.h"
#include "assert.h"
#include "file.h"
#include <cmath>
using namespace std;

#ifndef _WIN32
#include <cxxabi.h>
#include <sys/file.h>
#endif

#include "../db/jsobj.h"

namespace mongo {

    Nullstream nullstream;
    vector<Tee*>* Logstream::globalTees = 0;

    thread_specific_ptr<Logstream> Logstream::tsp;

    class LoggingManager {
    public:
        LoggingManager()
            : _enabled(0) , _file(0) {
        }
        
        void start( const string& lp , bool append ){
            uassert( 10268 ,  "LoggingManager already started" , ! _enabled );
            _append = append;

            // test path
            FILE * test = fopen( lp.c_str() , _append ? "a" : "w" );
            if ( ! test ){
                cout << "can't open [" << lp << "] for log file: " << errnoWithDescription() << endl;
                dbexit( EXIT_BADOPTIONS );
                assert( 0 );
            }
            fclose( test );
            
            _path = lp;
            _enabled = 1;
            rotate();
        }
        
        void rotate(){
            if ( ! _enabled ){
                cout << "LoggingManager not enabled" << endl;
                return;
            }

            if ( _file ){
#ifdef _WIN32
                cout << "log rotation doesn't work on windows" << endl;
                return;
#else
                struct tm t;
                localtime_r( &_opened , &t );
                
                stringstream ss;
                ss << _path << "." << terseCurrentTime(false);
                string s = ss.str();
                rename( _path.c_str() , s.c_str() );
#endif
            }
            
            
            FILE* tmp = fopen(_path.c_str(), (_append ? "a" : "w"));
            if (!tmp){
                cerr << "can't open: " << _path.c_str() << " for log file" << endl;
                dbexit( EXIT_BADOPTIONS );
                assert(0);
            }

            Logstream::setLogFile(tmp); // after this point no thread will be using old file

            if (_file){
                fclose(_file);
            }

            _file = tmp;
            _opened = time(0);
        }
        
    private:
        
        bool _enabled;
        string _path;
        bool _append;
        
        FILE * _file;
        time_t _opened;
        
    } loggingManager;

    void initLogging( const string& lp , bool append ){
        cout << "all output going to: " << lp << endl;
        loggingManager.start( lp , append );
    }

    void rotateLogs( int signal ){
        loggingManager.rotate();
    }

    // done *before* static initialization
    FILE* Logstream::logfile = stdout;

}

