LogXML - A XML Logging Class

/*

~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

                           LogXML 1.0
                       ------------------

  LogXML is a simple and free logging class for all purposes.
  You can use it freely und unlimited but give me credit
  where it's due.

  Source code is ready for DoxyGen (http://www.doxygen.org/).

  Written by Christian Richardt (cr@whizer.net).

  Release history:
    Mai 12, 2003: Version 1.0. First release.

~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

*/

/**
  \file    LogXML.cpp
  \brief   XML log class
  \date    2003-05-12
  \author  Christian Richardt (cr@whizer.net)
**/

#ifndef LOGXML_CPP
#define LOGXML_CPP


  #include <stdio.h>
  #include <string.h>
  #include <sys/timeb.h>
  #include <time.h>

  #include "LogXML.h"


    /**
      \brief   Constructor of LogXML
      \param   filename File name of log file
      \param   appName  Name of Application (optional)

      Opens the log file with specified name and writes the header.

      Attention: Existing files will be overwritten!
    **/
  LogXML::LogXML(char* filename, char* appName)
   {
      // copy filename
    m_strFilename = new char[ strlen(filename) ];
    strncpy(m_strFilename, filename, strlen(filename));

      // Try to open log file
    try
     { LogFile = fopen(filename, "w"); }
    catch(...)
     {
      char buf[200];
      sprintf(buf, "LogXML: Error opening file \"%s\".\n", filename);
      perror(buf);
      return;
     }

    Depth = 0; // root

      // Header
    LogXML::WriteData("<?xml version=\"1.0\" encoding=\"ISO-8859-1\" ?>\n");
    LogXML::WriteData("<?xml-stylesheet href=\"Log.xsl\" type=\"text/xsl\" ?>");
    LogXML::WriteLine("<LogFile>");

    Depth++; // one level down
    LogXML::WriteLine("AppName", appName);

    WriteTimestamp();
    WriteDateTime();
   }


    /**
      \brief   Go one level down.
      \param   message   Log entry
      \param   filename  Source file name (optional)
      \param   funcname  Function name (optional)
      \return  true (if successful)
    **/
  bool LogXML::goDown(char* message, char* filename, char* funcname)
   {
    bool res = true;

    res &= WriteLine("<LogItem>");
    Depth++;
    res &= WriteDateTime();
    if(filename != 0) { res &= WriteLine("Filename", filename); }
    if(funcname != 0) { res &= WriteLine("Function", funcname); }
    if(message  != 0) { res &= WriteLine("Entry", message); }

    return res;
   }


    /**
      \brief   Go one level up (if possible).
    **/
  void LogXML::goUp(void)
   {
    if(Depth > 1)
     {
      Depth--;
      WriteLine("</LogItem>");
     }
   }


    /**
      \brief   Write a log entry.
      \param   message   entry
      \param   filename  Source file name (optional)
      \param   funcname  Function name (optional)
      \return  true (if successful)

      <LogItem>
        <Date>YYYY-MM-DD</Date>
        <Time>HH:MM:SS.mmm</Time>
        <Filename>filename</Filename>
        <Function>function</Function>
        <Entry>message</Entry>
      </LogItem>
    **/
  bool LogXML::Log(char* message, char* filename, char* funcname)
   {
    bool res = true;
    goDown();

    if(filename != 0) { res &= WriteLine("Filename", filename); }
    if(funcname != 0) { res &= WriteLine("Function", funcname); }
    res &= WriteLine("Entry", message);

    goUp();
    return res;
   }



    /**
      \brief   Writes current date and time
      \return  true (if successful)

      <Date>YYYY-MM-DD</Date>
      <Time>HH:MM:SS.mmm</Time>
    **/
  bool LogXML::WriteDateTime(void)
   {
    char buf1[256]; // for strftime
    char buf2[256]; // result

    time_t ltime; time( &ltime );
    short mSec = (short)(long(1000*mtime())%1000);

      // Datum
    strftime( buf2, 255, "<Date>%Y-%m-%d</Date>", localtime(&ltime));
    bool res = LogXML::WriteLine(buf2); // write

      // Uhrzeit ...
      // hier wird der String <buf1> f�r strftime() gebastelt,
      // denn es m�ssen die Millisekunden integriert werden
    sprintf(buf1, "<Time>%%H:%%M:%%S.%03i</Time>", mSec);
    strftime( buf2, 255, buf1, localtime(&ltime)); // Auslesen des Ergebnisses
    res &= LogXML::WriteLine(buf2); // schreiben

    return res;
   }


    /**
      \brief   Writes current UNIX-Timestamp
      \return  true (if successful)
    **/
  bool LogXML::WriteTimestamp(void)
   {
    char buf[256];
    sprintf(buf, "<Timestamp>%.3f</Timestamp>", mtime());
    return LogXML::WriteLine(buf);
   }


    /**
      \brief   Writes a line (raw).
      \return  true (if successful)
    **/
  bool LogXML::WriteLine(char* data)
   {
    bool res = true;

    res &= WriteData("\n");
    for(int i=0; i<Depth; i++)
     { res &= WriteData("  "); }
    res &= WriteData(data);

    return res;
   }


    /**
      \brief   Writes a line: <tagname>contents</tagname>.
      \return  true (if successful)
    **/
  bool LogXML::WriteLine(char* tagname, char* contents)
   {
    char* buf = new char[ 2*strlen(tagname) + strlen(contents) + 10 ];
    sprintf(buf, "<%s>%s</%s>", tagname, contents, tagname);

    bool res = WriteLine(buf);

    delete[] buf;
    return res;
   }


    /**
      \brief   Write to Logfile
      \param   data String to write
      \return  true (if successful)
    **/
  bool LogXML::WriteData(char* data)
   {
    try
     { fwrite(data, strlen(data), 1, LogFile); }
    catch(...)
     {
      char buf[200];
      sprintf("LogXML: Could not write to file \"%s\".\n", m_strFilename);
      perror(buf);
      return false; // Error
     }
    return true; // Successful
   }


    /**
      \brief   Destructor; closes open tags and log file
    **/
  LogXML::~LogXML()
   {
    while(Depth > 1)
     { goUp(); }

    Log("Log File closed", FileName(__FILE__));

    Depth--; // up
    LogXML::WriteLine("</LogFile>"); // Last Line

      // Try to close log file
    try
     { fclose(LogFile); }
    catch(...)
     {
      char buf[200];
      sprintf(buf, "LogXML: Error closing file \"%s\".\n", m_strFilename);
      perror(buf);
     }

    delete[] m_strFilename;
   }



    /// base name of file
  char* FileName(char* strFile)
   {
    char* x = strrchr(strFile, '\\');
    if(x) { return (x+1); }
    else  { return "Error"; }
   }


    /// UNIX timestamp: seconds from 1970-01-01 00:00:00 (UTC)
  double mtime(void)
   {
    _timeb ts;
    _ftime( &ts );
    return (int)ts.time + (ts.millitm/1000.0);
   }



#endif // LOGXML_CPP