path: root/README

yChat; Homepage: www.yChat.org; Version 0.7.1-RELEASE

Copyright (C) 2003 Paul C. Buetow, Volker Richter
Copyright (C) 2004 Paul C. Buetow
-----------------------------------------------------------------

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 2
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, write to the Free Software
Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.
-----------------------------------------------------------------

YCHAT TABLE OF CONTENTS: 

0.0.0 YCHAT FEATURES //<<
1.0.0 REQUIREMENTS
1.1.0 TESTED PLATFORMS
1.2.0 IMPORTANT NOTICES
1.3.0 HOW TO OBTAIN YCHAT
1.3.1 INSTALLATION
1.3.2 INSTALLATION QUICK-START
1.3.3 MYSQL SETUP //<<
1.4.0 HOW TO USE SCREEN WITH YCHAT
1.5.0 CUSTOMIZATION
1.6.0 FILES
1.7.0 WRITING BUG REPORTS
1.8.0 CONTACT
1.9.0 YHTTPD CODE BASE GENERATION //<<

//<<*
0.0.0 YCHAT FEATURES

- Its free & portable -
yChat is developed under the GNU general public license and is based on GNU 
tools (gcc, gmake), other open source library stuff (such as libncurses etc.)
and should run on any POSIX capable operating system (such as all Linux based 
systems, FreeBSD, NetBSD, OpenBSD and other BSD-Systems and on UNICES like 
IRIX, HP-UX, Solaris etc.).

- There is no need for special chat clients -
yChat is web based, that means clients may only connect to the chat server 
with an normal web browser such as Microsoft Internet Explorer or any Gecko-
Engine powerd browsers like Mozilla, Firefox, Camino etc.

- It has features of a real HTTP webserver -
yChat runs completely stand alone and does not need another webserver to build
on like Apache and does not need to be run via any kind of CGI. yChat creates 
its own socket on a customized port (standard port: 2000) and seems to be a full
features HTTP web server to the clients (web browsers). 

The yChat code base can be converted to an yhttpd code base automaticaly. yhttpd
is the webserver subset of yChat which runs completely stand alone and provides
normal websites to the net. It also supports Common Gateway Interface (CGI)
scripting.

- Its fast and secure -
yChat is written in C++ which is faster than any Java based Chat-Server or any
server written in a scripting language like PHP, Python or Perl. As the
internal data structures hash maps are used to garuantee searching certain
values in O(1) amount of time. If a hash maps gets full, it will be rehashed.
The maximum usage in % can be redefined too (standard is 90%). Currently, yChat
has been measured providing over 5000 hits/requests per second (chat message
postings) on a FreeBSD based server box while using less than 2% of CPU usage
on a Athlon XP 1900+. Performance seems to be limited by your bandwith only. 
Also, each user gets its own session id (random string) with a standard length 
of 50 chars to authenticate each logged in user. The length of the session id 
can be redefined as well. Also, the session id will get md5-hashed optionally 
so thats even harder to reverse engineering the session ids of other users.

- Its HTML template based and easy to customize via XML based configuration -
All HTML sites are predefined as HTML-Template files and can be easily modified
to use with an customized web design. Also, a lot of yChat preferences can be
set in the main configuration file (ychat.conf). ychat.conf is completely written
in XML 1.0 which makes it easier to use the configuration options in programs of
3rd persons which may want to write some usefull tools for yChat.
yChat caches all HTML and web images to improve overall performance. If needed, the
cache can be cleared to recache new versions of the template files.

- Its language template based -
The administrator can easily create a new language in which all system messages
appear to the Chat-User. The predefined languages is english but others can be
added easily. The language can be edited in the XML based configuration file.

- MySQL based database -
Registered users are stored in a MySQL database. C++ Programmers may feel free
to replace the database wrapper class (data.h) with another database routines
to use other databases such as PostgreSQL, SQLite or a text based database etc.
If wished, you can disable database support in the pre-compile options.

- It has an administration interface -
yChat includes an ncurses based administration interface which tracks some
interesting statistics and system messages and enables you to do certain
administrative tasks. In addition, you can switch to the CLI (command line
interface) mode of the administration interface in order to be provided with
more available functions (like keeping track of the current system usage etc.).
If you dont like ncurses and/or the CLI you can disable both options in the pre-
compile options. 

- It has logging capabilities -
The logging manager keeps track to all yChat system messages (such as users 
wich log in and out, modules which are loaded, MySQL queries etc.). Also, an
Apache-Style combined log file format is created by yChat (you can parse this
logfile with any Apache logfile parser like awstats etc.). And last but not
least, all public messages of all available rooms will be logged to disk as 
well . To improve performance, you can define the logging puffer (standardly
new logs will be written to disk after each 20 lines). If you want to log
everything immediately, you can reset this option to 1 in ychat.conf.

- Its modular -
All chat commands are realized through dynamic loadable module files which can
be recompiled and reloaded without restarting the whole yChat server. Also 
HTML-Sites with certain tasks can be compiled as a module like 
mods/html/yc_register.so, mods/html/yc_options.so and mods/html/yc_colors.so
etc. so you can also program your dynamic yChat websites in C++.

- Its multi threaded (POSIX threads) -
There is only one main process which spawns several threads, each for its own
unique task. For example one thread is used to handle the socket manager which
waits for incoming TCP/IP requests, another thread schedules the system timer
which proves if clients are still active or frees not needed memory in certain
time intervals (see also "Garbage collector"). Also, each Chat-User gets it own
thread. There is no need of memory wastage by creating for each task a new
process. All User-Threads are managed by a thread pool to avoid CPU wastage
creating every time a new thread by reusing thread objects which have done its
jobs already and have been readded into the queue of the thread pool. The 
standard sizes of the queue and the total pool size can be set in ychat.conf.

- Its using a smart garbage collection engine -
All users and rooms which dont have to be kept in the main memory (because the
user has logged out or the room has been destroyed because it was empty) will
not be deleted immediately but be placed for about 10 minutes in the yChat
garbage collector. Each time a new room is created the systems checks the
garbage to reuse an inactive room object. If a certain user wants to log in, the
system checks if he is already present in the garbage collector. If yes, he will
be reactivated without wasting expensive database queries to fetch the user's
options. This improves overall performance on heavily loaded yChat servers if a
lot of user and room objects are created and destroyed frequently.
//*>>

1.0.0 REQUIREMENTS: 

- GNU GCC G++ 3.4 or 3.3 or 3.2 or 3.1 
  The GNU C++ compiler. G++ version 3.0 or 2.x does NOT work.

- GNU make 3.80 (gmake) or higher
  If you dont have a gmake executable but make is gnu make then you need
  to add a symlink or alias from gmake to make.
  yChat Makefiles only have been tested with GNU make and may not work with
  other make versions.

//<<*
- mysql-client 4.x (3.x may do too but is not supported)
  Includes libmysqlclient and the mysql.h header files.

//*>>
- ncurses 5.x   
  Includes libncurses and the ncurses.h header files.

- Screen
  Only needed if yChat should run in background with
  ncurses or CLI enabled.

- Perl 5.x
  Is needed for some scripts. Is not needed if you use precompiled binaries.

1.1.0 TESTED PLATFORMS:

The following platforms have been tested with success. If you find out that
a listed platform did not work at all please contact me:

  Operating system (arch)	GNU G++		GNU make
- FreeBSD 5.2.1-RELEASE (i386)	3.3.3 		3.80		
- FreeBSD 4.9-RELEASE (i386)	3.3.4		3.80
- FreeBSD 4.10-RELEASE (i386)	3.4.1		3.80
- Gentoo Linux 2004.2 (i386)	3.3.2		3.80
- OpenBSD 3.6 MP (i386)		3.3.2		3.80
- Slackware Linux 10.0 (i386)	3.4.0		3.80 
- SUSE Linux 8.0, G (i386)	3.3.1		3.80

Other platforms like Linux based systems, other BSD-Systems or UNICES
are very likely to work too. 

1.2.0 IMPORTANT NOTICES:

Before you compile the source you have to be sure to use at least GCC
version 3.1 with pthreads enabled. ( Type gcc -v to check it ).
GCC 2.95 and 3.0 did not work while testing and WON'T BE SUPPORTED!
If you like to support yChat++, please write us an email and tell what 
you can/like/would help ;-]. Please also take a look at the yChat++
homepage which is located at http://www.yChat.org.

1.3.0 HOW TO OBTAIN YCHAT++:

yChat can be downloaded as a source package or through CVS. 

The packages are located at http://www.yChat.org -> Sourcecode -> 
Packages or go to http://pub.buetow.org/yChat/CPP-yChat .

For CVS download type:

cvs -d:pserver:anonymous@buetow.org:/usr/home/cvs/cvsroot login
( You will be asked for a password. Use "just enter" ).

vs -z3 -d:pserver:anonymous@buetow.org:/usr/home/cvs/cvsroot co ychat
( The sources will be copied into your local folder )

cvs -d:pserver:anonymous@buetow.org:/usr/home/cvs/cvsroot logout
( Logs your CVS session out ).

Now you may continue with the installation.

1.3.1 INSTALLATION:

Invoke "./configure". Afterwards you will get prompted with the before-compile
options of yChat. After choosing those options you are ready to type "gmake"
afterwards. 

//<<*
If you have choosen MySQL database support, then take a look at section 1.3.2 
how to setup a valid database table. Be also sure to enter the valid MySQL 
accessing data in the yChat configuration file which is normally located in 
the etc/ychat.conf file if not changed by you with the yChat configurator.
//*>>

You may also invoke gmake with the following options (the PREFIX can be set
in the yChat configurator which will be launched by the top configure script
or gmake config):

 gmake or gmake all (compiles everything, also modules)
 gmake base (only compiles the base)
 gmake base_start (only compiles the base and starts the server)
 gmake clean (cleans everything)
 gmake clean_base (only cleans the base obj and rpo files)
 gmake clean_modules (only cleans the modules .so files) 
 gmake config (runs yChat configurator)
 gmake deinstall (deinstalls ychat from PREFIX)
 gmake gpl (shows the GNU General Public License)		
 gmake help (shows all available ychat gmake targets)
 gmake install (installs ychat to PREFIX)
 gmake modules (only compiles modules)
 gmake mrproper (same as gmake clean plus removing all temp files) 
 gmake setup (runs all configure scripts and afterwards gmake all)
 gmake start (compiles everything and starts the server)
 gmake stats (generates ychat statistics)
 gmake uninstall (same as deinstall)
 gmake version (shows the current version of yChat)
//<<*
 gmake yhttpdbase (generates an yhttpd code base)
//*>> (See section 1.9 to read about this marks)

Example: "gmake all install clean" compiles everything, installs it to PREFIX
and cleans the source directories.

Now its time to run the server with ./bin/ychat.

Aferwards point your webbrowser to http://yourip:port !

... have fun :-).

1.3.2 INSTALLATION QUICK START:

If you in hury, then you may just type gmake setup. In the yChat configurator
you may just choose all the default values. If done, yChat will get compiled
and is ready to run with ./bin/ychat! 

//<<*
1.3.3 MYSQL SETUP

If you chose to use MySQL database support you have to create a valid database
to use with yChat.

Create a new MySQL database called 'ychat' and type the following command into
a MySQL command line client of your choice:

USE ychat
CREATE TABLE `user` ( 
  `uid` int(10) NOT NULL auto_increment, 
  `nick` varchar(30) NOT NULL default '', 
  `password` varchar(30) NOT NULL default '', 
  `color1` varchar(30),
  `color2` varchar(30),
  `email` varchar(50) default '-', 
  `registerdate` varchar(30) default '-', 
  `logincounter` varchar(10) default '0', 
  `status` char(1) default '3', 
  PRIMARY KEY  (`uid`), 
  KEY `uid` (`uid`) 
) TYPE=MyISAM;
GRANT ALL PRIVILEGES ON ychat.* to ychat@localhost IDENTIFIED BY "yctest";

This database uses the default MySQL access informations which are stored in the
ychat.conf file.
//*>>

1.4.0 HOW TO USE SCREEN WITH YCHAT:

If you are running yChat in ncurses mode you might want to install
the tool which is called "screen". This will enable you putting the
ncurses interface into the background, closing the terminal session
and reusing the interface later through another terminal. 

Just do:
 
 screen -S ychat ./bin/ychat ( creates a new session and starts yChat in it )
 ctrl+d+a ( will detach the yChat session )
 ( closing the terminal )
 ( opening a new terminal )
 screen -r ychat ( will return you to the yChat process )

Screen will terminate automaticaly if all processes in its sessions are 
terminated.

For a closer look read the screen manual page ( man screen ). 

1.5.0 CUSTOMIZATION:

If you like to customize the design/layout/language of yChat, you will have 
to edit src/msgs.h and src/glob.h before you compile the sources. Afterwards 
you can change the html-template files which are placed in the html/ 
subdirectory and the language-templates which are placed in the XML config 
file (etc/ychat.conf).

Notice, that you dont have to edit the src/glob.h file by hand any more, its
already done by the top ./configure script for you.

You can edit the etc/ychat.conf to fit your needs. If you dont want to change
the config file, then you also can use ychat start parameters.

Exmpl: ./bin/ychat -o chat.database.password secretpassword

You can also use multiple words for a specific option.

Exmpl: ./bin/ychat -o ychat.version "word1 word2 word3"

will overwrite the default database password value of the ychat.conf. You can
do this with every configuration element by adding several -o option value 
arguments to the start command.

Dynamic loadable modules can be found in the mods/ subdirectory. (chat 
commands are realized through modules too). Sources of modules can be found
in src/mods instead. If you want to create a new module just create a new
.cpp file and run in src/mods the ./configure script again. Next time
you run gmake your new module gets compiled.

All messages defined in the msgs.h file contain server messages only ( a chat
user never wont read them, only the administrator will get to see them ).

1.6.0 FILES:

etc/ychat.conf  - The yChat configuration file
html/*		- The html template files
src/*		- The yChat base sources
src/mods/*	- The dynamic loadable modules sources
scripts/*	- Some nice scripts needed for building & co.

The following is created by building yChat:
obj/*		- The object files of the compiled yChat base 
mods/*		- The compiled dynamic loadable modules
bin/ychat	- The yChat binary (linked by the object files)

Customizable source files (if changed you need to run gmake clean all) 
src/glob.h	- Contains some global building options
src/msgs.h	- Defines some server side messages


1.7 WRITING BUG REPORTS

How to submit a good bug report?

Send them to Bug@yChat.org.

First you should give the following information:
- yChat version, if CVS (or devel. tarball) then which day?
- operating system / distribution and it's version
- when did it crash? did you do something? can you reproduce the crash?

Getting backtrace of the crash also helps a lot, especially if yChat crashes 
randomly. If after crash you see text:

 "segmentation fault (core dumped)" 

It writes a file named "core" or "ychat.core" depending on your OS to directory
where you started yChat. If it doesn't print the "(core dumped)" or you can't
find the core file, you'll have to raise the limit for max. core file size
before running yChat. To do this, say:

 ulimit -c unlimited 

So, if you have the core file and GNU debugger (gdb), you can get the 
backtrace with:

 gdb ./bin/ychat ychat.core 
 bt 

Paste all the lines starting from line having #0 at the beginning.

Here's an example session:

 in reqp::parse(thrd*, std::string, std::map<std::string, std::string, 
 std::less<std::string>, std::allocator<std::pair<std::string const, std::string> > >&) ()
 (gdb) bt
 #0 0x0805c287 in reqp::parse(thrd*, std::string, std::map<std::string, 
 std::string, std::less<std::string>, std::allocator<std::pair<std::string
 const, std::string> > >&) ()
 #1 0x0806060f in sock::read_write(thrd*, int) ()
 #2 0x080612ba in thrd::run() ()
 #3 0x0805a3b8 in pool::run_func(void*) ()
 #4 0x0805a375 in pool::tpool_thread(void*) ()
 #5 0x281d44ae in _thread_start () from /usr/lib/libc_r.so.5
 (gdb) 

If you dont get such a gdb output, you need to recompile the yChat using
debuggig symbols. You can do it this way:

cd ychat
gmake mrproper
./configure -g3 -ggdb
gmake start

1.8 CONTACT:

You may contact us through the following addresses:

- Homepage
  The yChat homepage is located at http://www.yChat.org

- E-Mail
  Paul C. Buetow: Snooper at yChat point org ( core developer )
  Volker Richter: Rover at yChat dot org ( core developer )
  Mail at yChat dot org ( reaches everybody of yChat )
 
- ICQ
  Paul C. Buetow: 11655527

- IRC
  #Ychat and #Coding at irc.german-elite.net  

//<<*
1.9 YHTTPD CODE BASE GENERATION

See docs/yhttpd.txt
//*>>