cgit - cgi for git


This is an attempt to create a fast web interface for the git scm, using a 
frontside cache to decrease server io-pressure.

When cgit is invoked, it looks for a cached page matching the request. If no
such cachefile exist (or it has expired), it is (re)generated. Finally, the
cachefile is returned to the client.

If the cachefile has expired, but cgit is unable to lock the cachefile, the 
client will get the stale cachefile after all. This is done to favour page
throughput over page freshness.

Also, when a cachefile is generated, a few cache-related http-headers are
created: "Modified" is set to current time(2), while "Expires" is set to 
time(2) + <cachefile TTL> * 60 (unless the TTL is negative, in which case it
is read as "60 * 60 * 24 * 365"). This is done to avoid repeated requests for
already visited pages.

The following cache-related options can be set in /etc/cgitrc:

  cache-root=<path>           root directory for cache files
  cache-root-ttl=<min>        TTL for the repo listing page
  cache-repo-ttl=<min>        TTL for repo summary pages
  cache-dynamic-ttl=<min>     TTL for pages with symbolic references
  cache-static-ttl=<min>      TTL for pages with sha1 references

The cachefiles are split into different directories, based on the requested
repository and page:

  Repo listing:  <cachedir>/index.html
  Repo summary:  <cachedir>/<repo>/index.html
  Repo subpage:  <cachedir>/<repo>/<page>/<querystring>.html