# libtommath

This is the git repository for [LibTomMath](http://www.libtom.net/LibTomMath/), a free open source portable number theoretic multiple-precision integer (MPI) library written entirely in C.

## Build Status

### Travis CI

master: [![Build Status](https://github.com/libtom/libtommath/actions/workflows/main.yml/badge.svg?branch=master)](https://github.com/libtom/libtommath/actions/workflows/main.yml?query=branch%3Amaster+++)

develop: [![Build Status](https://github.com/libtom/libtommath/actions/workflows/main.yml/badge.svg?branch=develop)](https://github.com/libtom/libtommath/actions/workflows/main.yml?query=branch%3Adevelop+++)

### AppVeyor

master: [![Build status](https://ci.appveyor.com/api/projects/status/b80lpolw3i8m6hsh/branch/master?svg=true)](https://ci.appveyor.com/project/libtom/libtommath/branch/master)

develop: [![Build status](https://ci.appveyor.com/api/projects/status/b80lpolw3i8m6hsh/branch/develop?svg=true)](https://ci.appveyor.com/project/libtom/libtommath/branch/develop)

### ABI Laboratory

API/ABI changes: [check here](https://abi-laboratory.pro/tracker/timeline/libtommath/)

### Pre-built packages

We sometimes upload `deb` packages of the latest state from the develop branch to [packagecloud.io](https://packagecloud.io/libtom/packages).

Use those packages with caution and at your own discretion.

## Summary

The `develop` branch contains the in-development version. Stable releases are tagged.

Documentation is built from the LaTeX file `doc/bn.tex` and available as PDF for each release.
This PDF is also created as build artifact on each CI run.

There is also limited documentation in `tommath.h`.

Originally the library contained a document, `tommath.pdf`, which describes the goals of the project and many of the algorithms used at the time.
This document has been removed since it can't be built anymore and nobody spent the time to fix and update it.
The latest valid update to that document was done in version [`0.39`](https://github.com/libtom/libtommath/releases/tag/0.39) of the library and it is contained within that tarball.

The project can be build by using `make`. Along with the usual `make`, `make clean` and `make install`,
there are several other build targets, see the makefile for details.
There are also makefiles for certain specific platforms.

## Testing

Tests are located in `demo/` and can be built in two flavors.
* `make test` creates a stand-alone test binary that executes several test routines.
* `make mtest_opponent` creates a test binary that is intended to be run against `mtest`.
  `mtest` can be built with `make mtest` and test execution is done like `./mtest/mtest | ./mtest_opponent`.
  `mtest` is creating test vectors using an alternative MPI library and `test` is consuming these vectors to verify correct behavior of ltm

## Building and Installing

Building is straightforward for GNU Linux only, the section "Building LibTomMath" in the documentation in `doc/bn.pdf` has the details.

### CMake support

The project provides support for the CMake build system.

```
git clone https://github.com/libtom/libtommath.git
mkdir -p libtommath/build
cd libtommath/build
cmake ..
make -j$(nproc)
```

A shared library build can be done by setting `-DBUILD_SHARED_LIBS=On` when invoking the `cmake` command.