RaptorQ is a Forward Error Correction algorithm designed to deliver your data
efficiently and without retransmissions for lost packets.

After sending K packets of your data as-is, RaptorQ generates as many repair
symbols as you need. Once the receiver has at least K symbols, be it the source
symbols, repair symbols or any combination of the two, it can reconstruct the
whole input it was meant to receive.

This is called a Fountain code, and RaptorQ is the latest and most efficient
code in this category.


libRaptorQ implements RFC6330, which specifies the RaptorQ algorithm.
NOTE: heavy cluster testing is needed to claim compliance with the
RFC. As we do not have the resources, we do not make such a claim.

libRaptorQ is entirely written in C++11, and uses eigen to handle matrix
manipulation.


Currently it's only been tested under Linux, but should work well under
*BSD and MacOSX, too.

Windows *should* work too, provided you use a complier that understands C++11
(hint: you might have some problems with VisualC++, but that's not a C++
compiler anyway)



##############
#
# The Source Code
#
##############

Although things seems to work, no stable release has been released yet.

This means you can only check this out with git.

to check out the repository:

$ git clone https://github.com/LucaFulchir/libRaptorQ.git

you can also get it from our main server:

$ git clone git://git.fenrirproject.org/libRaptorQ.git


-- GPG source check --
once you have cloned it, it's always a good thing to check the repository gpg
signatures, so you can import my key with:

$ gpg --keyserver pgp.mit.edu --recv-key D42DDF0A

please check the full fingerprint, it should be like this:

$ gpg2 --fingerprint D42DDF0A
 pub   rsa3072/D42DDF0A 2015-01-01 [expires: 2016-01-01]
       Key fingerprint = AB35 E45F 5CA5 E35B 8B55  818F 0157 D133 D42D DF0A
 uid       [ unknown] Luca Fulchir (2015 key) <luker@fenrirproject.org>
 

Now you have the source, and the key, it's enough to check the signature of the
last commit:

$ git log -n 1 --show-signature

The important part is that you get something like this:

 gpg: Signature made Fri 27 Mar 2015 20:59:59 CET using RSA key ID D42DDF0A
 gpg: Good signature from "Luca Fulchir (2015 key) <luker@fenrirproject.org>"
 [unknown]
 gpg: WARNING: This key is not certified with a trusted signature!
 gpg:          There is no indication that the signature belongs to the owner.
 Primary key fingerprint: AB35 E45F 5CA5 E35B 8B55  818F 0157 D133 D42D DF0A
 Author: Luca Fulchir <luker@fenrirproject.org>

And as long as you got the right key, and you find the "gpg: Goog signature",
you can be sure you have the right code.



##############
#
# Install
#
##############

Before building libRaptorQ, make sure your system has the eigen3 library
headers, or it won't compile.

Eigen3 is the only dependency of libRaptorQ


The build system uses CMake. So enter the source directory and we'll create a
directory and build everything there:

$ mkdir build
$ cd build

$ cmake -DCMAKE_BUILD_TYPE=Release ../

$ make -j 4

Optionally: build the pdf documentation (requires latex)
$ make docs

$ make install


And you are set. You can customize lots of things in the installation, all by
telling CMake what you need.

adding "-DCMAKE_CXX_COMPILER=clang++"
will use clang as the compiler.

adding "-DSTDLIB=libc++"
will use clang libc++ library for the C++ standard library.

adding "-DCMAKE_INSTALL_PREFIX=/usr"
might help you follow your distribution guidelines.

The supported release types are:
- Debug
- MinSizeRel
- Release
The names should be self-explanatory.
Use them with "-DCMAKE_BUILD_TYPE=release"