Small Libravatar implementation in C.

1. Synopsis
2. Install
3. Tests
4. License

libravatar.cgi is an open source CGI written in C implementing the Libravatar protocol. Its goal is to be minimal, secure and BCHS.

This implementation only serves existing avatars in the PNG format located in /var/www/htdocs/avatars and does not provide any way to upload a file. This should be the responsability of a separate system.

To request an avatar the following steps should be done :

• Create a hash of a lowercased email address using md5 or sha1 ;
• Call the CGI with a HTTP request on the path /avatar/$hash.

A few options are accepted as GET parameters :

• size: control the size of the image, must be between 1 and 512 with a default value of 80 ;
• default: 404, mm and blank are supported ;
• rating: only kept for compatibility with Gravatar this option does nothing ;
• forcedefault: y or n.

The current version is not portable and only runs on OpenBSD.

• C compiler ;
• kcgi ;
• libpng

Configure your http server of choice to receive this CGI. An example and minimalistic configuration file is provided in the config/ folder for OpenBSD httpd(8).

# mkdir /var/www/htdocs/avatars/
# cp config/mm.png /var/www/htdocs/avatars/
# cp config/default.png /var/www/htdocs/avatars/
$ make
# make install

Although the code is not portable yet the Makefile is and should work with GNU make.

Basic regression tests are provided in the regress/ folder. They test this implementation and two others: the official Libravatar and ivatar.

All sources use the ISC license excepts resample.{c,h}, jpegscale.c and pngscale.c which use the MIT license. This files are sourced from the liboil project.