How to compile LAN Messenger

You need Qt (https://www.qt.io/) to compile.
I built LAN Messenger using Qt 5.11, so you probably need that or a
later version.

You also need OpenSSL (http://www.openssl.org/)
I used version 1.0.2q, so you know what to get.
Please read the OpenSSL section for more information.

The application consists of two projects - lmc and lmcapp. lmcapp is
just an extension of the qtsingleapplication project released by the
Qt people. I have added a few functions to support multilanguage UI.

The main project is lmc which contains the entire application. I have
included the project files for both projects.

Extract both folders. Make sure the directory hierarchy is maintained.
"lmc" and "lmcapp" should be folders at same level. Make sure the
dependency paths of lmc are set to the correct locations. It depends
on lmcapp and openssl, in addition to the standard Qt libraries.

The code is identical for all platforms, but there are a few differences
in the way application is built and run on each platform. Please read
the platform specific notes to know more.

Note: I used Qt Creator IDE with gcc compiler on all platforms. If you
are using any other IDE and/or compiler and run into any issue, I can
only provide generic help.

Important: Its better if your project paths do not contain any white spaces.
Some tools do not work properly with paths containing spaces. Use paths that
do not have spaces to avoid headaches down the lane.
Saving project files to your dektop is a BAD idea.

Compiling/Installing OpenSSL

If precompiled binary distribution of OpenSSL is available for your
platform, you can use it instead of building from source.

The steps for compiling OpenSSL varies depending on your platform.
The package that you get from OpenSSL website gives detailed instructions
on how to compile on all supported platforms. OpenSSL itself may need
additional software packages to compile depending on your system.

Make sure that OpenSSL is built as a shared library.

Windows

Get the precompiled binary distribution of OpenSSL from
http://www.slproweb.com/products/Win32OpenSSL.html

This version of LAN Messenger was built with the package named
"Win32 OpenSSL v1.0.2q". Download the package and install to a folder
called "openssl" which should be at the same level as the folder "lmc".
While installing, make sure that the option to copy DLLs to the OpenSSL
binaries directory is selected in the Additional Tasks page.

Linux/X11

Many Linux distributions come with pre-compiled OpenSSL packages. If your
system has one, you may be able to link the project to it. If your system
lacks the package, or if you are unable to link with it, you need to build
OpenSSL from source.

Specify the "shared" switch to ensure that OpenSSL is built as a shared
library.

Mac OS X

Mac OS X ships with a binary package of OpenSSL, so there is not need to
compile. You can link the project with this package even if it is an older
version than the one found on OpenSSl web site.

Compiling LAN Messenger

Some custom scripts are used for automating part of the compilation and setup
of LAN Messenger. These scripts rely on an environment variable called
QTDIR that should contain the path where Qt libraries are installed. More
specifically, it should point to the parent folder of the bin and lib folders
where Qt binaries reside. Eg: C:\Qt\4.8.0 on Windows.

Refer PLATFORM_SPECIFIC.TXT for additional details about setting up the build
environment on respective platforms.

Compiling LAN Messenger on Windows

Its possible to compile using other build chains/IDEs, but its better
to stick to Qt Creator and gcc tool chain.

OpenSSL should be built/installed first. I recommend using a folder at
the same level as "lmc" folder as the OpenSSL folder.

Next build "lmcapp" project. All the files needed are present inside
lmcapp\src folder. This project should be built as a shared library.
The outputs of this project are lmcapp.dll and lmcapp.a, which will be
created in lmcapp\lib folder. The .dll file should be moved to
lmcapp\bin and the .a file should be left in lmcapp\lib. In case of
debug build, the output files will be lmcappd.dll and lmcappd.a

Finally build "lmc" project. This project references both OpenSSL and
lmcapp, so the correct paths to headers and libraries should be set
first.
The headers of lmcapp should be in lmcapp\include
The libraries of lmcapp should be in lmcapp\lib
The headers of OpenSSL should be in openssl\include
The libraries of OpenSSL should be in openssl\lib
Note: OpenSSL paths may be different depending on how it was built/installed
in your system.

Once you have built lmc, run the "buildwin32.bat" batch file found in
the src\scripts folder. This script compiles the translation files, builds
the resources into a separate binary file and copies the application
dependencies to the output folder. The path of output directory should
be passed as a parameter for this script. The script depends on the QTDIR
environment variable, so make sure it is set correctly. You can probably
add the execution of this script as a custom build step in your IDE. That
way it will be automatically called every time you build the project.

Compiling LAN Messenger on X11/Linux

OpenSSL should be built first. I recommend using a folder at the same
level as "lmc" folder as the OpenSSL folder.

Next build "lmcapp" project. All the files needed are present inside
lmcapp/src folder. This project should be built as a shared library.
The outputs of this project is liblmcapp.1.0.0.so, which will be
created in lmcapp/lib folder.

Finally build "lmc" project. This project references both OpenSSL and
lmcapp, so the correct paths to headers and libraries should be set
first.
The headers of lmcapp should be in lmcapp/include
The libraries of lmcapp should be in lmcapp/lib
The headers of OpenSSL should be in openssl/include
The libraries of OpenSSL should be in openssl/lib
Note: OpenSSL paths may be different depending on how it was built/installed
in your system.

Once you have built lmc, run the "buildx11" shell script found in the
src/scripts folder. This script performs the same actions as its Windows
counterpart. The QTDIR variable defined in the script should contain the
correct path to Qt libraries. You can add the execution of this script as
a custom build step to automate the whole process. If you get an error
while executing the script, edit the script to make sure that the Qt
plugins path in the script is correct.

Compiling LAN Messenger on Mac OS X

Build "lmcapp" project. All the files needed are present inside
lmcapp/src folder. This project should be built as a shared library.
The outputs of this project is liblmcapp.1.0.0.dylib, which will be
created in lmcapp/lib folder.

Finally build "lmc" project. This project references lmcapp, so the
correct paths to headers and libraries should be set first.
The headers of lmcapp should be in lmcapp/include
The libraries of lmcapp should be in lmcapp/lib

Note: There is no need to link to OpenSSL since it is present as a system
library on Mac OS X.

Once you have built lmc, run the "buildmacos" shell script found in the
src/scripts folder. This script performs the same actions as its Windows
counterpart. The script depends on the QTDIR environment variable, so make
sure it is set correctly. You can add the execution of this script as a
custom build step to automate the whole process. If you get an error while
executing the script, edit the script to make sure that the Qt plugins
path in the script is correct.

Note: On Mac OS X, option to start LAN Messenger on startup will not work.
This is a platform dependent function and I have not implemented it.

Audio playback support

LAN Messenger can play sounds to accompany certain events. This behaviour
is customizable in the Preferences dialog. Sound functions are provided
by Qt which in turn depend on different subsystem on each platform. This
should not be a problem in Windows and Mac. However on Linux, Qt needs the
Network Audio System for sound functions. If NAS is not available the
application will not play sounds. Sound options will be grayed out in the
Preferences dialog.

System tray support

On desktops that do not have a system tray, the system tray options will
be grayed out in the Preferences dialog.