index : cgit

:man source:   cgit
:man manual:   cgit

CGITRC(5)
========


NAME
----
cgitrc - runtime configuration for cgit


SYNOPSIS
--------
Cgitrc contains all runtime settings for cgit, including the list of git
repositories, formatted as a line-separated list of NAME=VALUE pairs. Blank
lines, and lines starting with '#', are ignored.


LOCATION
--------
The default location of cgitrc, defined at compile time, is /etc/cgitrc. At
runtime, cgit will consult the environment variable CGIT_CONFIG and, if
defined, use its value instead.


GLOBAL SETTINGS
---------------
about-filter::
	Specifies a command which will be invoked to format the content of
	about pages (both top-level and for each repository). The command will
	get the content of the about-file on its STDIN, the name of the file
	as the first argument, and the STDOUT from the command will be
	included verbatim on the about page. Default value: none. When no
	about-filter is set, the readme is escaped and served as plain text.
	A bundled Lua filter, about-render.lua, renders markdown, man pages
	and plain text when about-filter points at it. See also: "FILTER API".

agefile::
	Specifies a path, relative to each repository path, which can be used
	to specify the date and time of the youngest commit in the repository.
	The first line in the file is used as input to the "parse_date"
	function in libgit. Recommended timestamp-format is "yyyy-mm-dd
	hh:mm:ss". You may want to generate this file from a post-receive
	hook. Default value: "info/web/last-modified".

auth-filter::
	Specifies a command that will be invoked for authenticating repository
	access. Receives quite a few arguments, and data on both stdin and
	stdout for authentication processing. Details follow later in this
	document. If no auth-filter is specified, no authentication is
	performed. Default value: none. See also: "FILTER API".

branch-sort::
	Flag which, when set to "age", enables date ordering in the branch ref
	list, and when set to "name" enables ordering by branch name. Default
	value: "name".

cache-about-ttl::
	Number which specifies the time-to-live, in minutes, for the cached
	version of the repository about page. See also: "CACHE". Default
	value: "15".

cache-dynamic-ttl::
	Number which specifies the time-to-live, in minutes, for the cached
	version of repository pages accessed without a fixed SHA1. See also:
	"CACHE". Default value: "5".

cache-repo-ttl::
	Number which specifies the time-to-live, in minutes, for the cached
	version of the repository summary page. See also: "CACHE". Default
	value: "5".

cache-root::
	Path used to store the cgit cache entries. Default value:
	"/var/cache/cgit". See also: "MACRO EXPANSION".

cache-root-ttl::
	Number which specifies the time-to-live, in minutes, for the cached
	version of the repository index page. See also: "CACHE". Default
	value: "5".

cache-scanrc-ttl::
	Number which specifies the time-to-live, in minutes, for the result
	of scanning a path for git repositories. See also: "CACHE". Default
	value: "15".

case-sensitive-sort::
	Sort items in the repo list case sensitively. Default value: "1".
	See also: repository-sort, section-sort.

cache-size::
	The maximum number of entries in the cgit cache. When set to "0",
	caching is disabled. See also: "CACHE". Default value: "0"

cache-snapshot-ttl::
	Number which specifies the time-to-live, in minutes, for the cached
	version of snapshots. See also: "CACHE". Default value: "5".

cache-static-ttl::
	Number which specifies the time-to-live, in minutes, for the cached
	version of repository pages accessed with a fixed SHA1. See also:
	"CACHE". Default value: -1".

clone-prefix::
	Space-separated list of common prefixes which, when combined with a
	repository url, generates valid clone urls for the repository. This
	setting is only used if `repo.clone-url` is unspecified. Default value:
	none.

clone-url::
	Space-separated list of clone-url templates. This setting is only
	used if `repo.clone-url` is unspecified. Default value: none. See
	also: "MACRO EXPANSION", "FILTER API".

commit-filter::
	Specifies a command which will be invoked to format commit messages.
	The command will get the message on its STDIN, and the STDOUT from the
	command will be included verbatim as the commit message, i.e. this can
	be used to implement bugtracker integration. Default value: none.
	See also: "FILTER API".

commit-sort::
	Flag which, when set to "date", enables strict date ordering in the
	commit log, and when set to "topo" enables strict topological
	ordering. If unset, the default ordering of "git log" is used. Default
	value: unset.

css::
	Url which specifies the css document to include in all cgit pages.
	Default value: "/cgit.css".  May be given multiple times, each
	css URL path is added in the head section of the document in turn.

email-filter::
	Specifies a command which will be invoked to format names and email
	address of committers, authors, and taggers, as represented in various
	places throughout the cgit interface. This command will receive an
	email address and an origin page string as its command line arguments,
	and the text to format on STDIN. It is to write the formatted text back
	out onto STDOUT. Default value: none. See also: "FILTER API".

embedded::
	Flag which, when set to "1", will make cgit generate a html fragment
	suitable for embedding in other html pages. Default value: none. See
	also: "noheader".

enable-blame::
	Flag which, when set to "1", will allow cgit to provide a "blame" page
	for files, and will make it generate links to that page in appropriate
	places. Default value: "0".

enable-commit-graph::
	Flag which, when set to "1", will make cgit print an ASCII-art commit
	history graph to the left of the commit messages in the repository
	log page. Default value: "0".

enable-filter-overrides::
	Flag which, when set to "1", allows all filter settings to be
	overridden in repository-specific cgitrc files. Default value: none.

enable-cache-list::
	Flag which, when set to "1", exposes the "ls_cache" page. That page
	lists the cache directory path and the URLs of requests other visitors
	made, so it is disabled by default and should stay off on any instance
	where that disclosure matters. Default value: "0".

enable-follow-links::
	Flag which, when set to "1", allows users to follow a file in the log
	view.  Default value: "0".

enable-help::
	Flag which, when set to "1", adds a "help" tab to the repository index
	with a built-in guide to the interface, covering the URL patterns for
	common workflows such as comparing two tags or downloading a snapshot.
	Default value: "1".

enable-git-config::
	Flag which, when set to "1", will allow cgit to use git config to set
	any repo specific settings. This option is used in conjunction with
	"scan-path", and must be defined prior, to augment repo-specific
	settings. The keys gitweb.owner, gitweb.category, gitweb.description,
	and gitweb.homepage will map to the cgit keys repo.owner, repo.section,
	repo.desc, and repo.homepage respectively. All git config keys that begin
	with "cgit." will be mapped to the corresponding "repo." key in cgit.
	Default value: "0". See also: scan-path, section-from-path.

enable-http-clone::
	If set to "1", cgit will act as a dumb HTTP endpoint for git clones.
	You can add "http://$HTTP_HOST$SCRIPT_NAME/$CGIT_REPO_URL" to clone-url
	to expose this feature. If you use an alternate way of serving git
	repositories, you may wish to disable this. Default value: "1".

enable-html-serving::
	Flag which, when set to "1", will allow the /plain handler to serve
	mimetype headers that result in the file being treated as HTML by the
	browser. When set to "0", such file types are returned instead as
	text/plain or application/octet-stream. Default value: "0". See also:
	"repo.enable-html-serving".

enable-index-links::
	Flag which, when set to "1", will make cgit generate extra links for
	each repo in the repository index (specifically, to the "summary",
	"commit" and "tree" pages). Default value: "0".

enable-index-owner::
	Flag which, when set to "1", will make cgit display the owner of
	each repo in the repository index. Default value: "1".

enable-log-filecount::
	Flag which, when set to "1", will make cgit print the number of
	modified files for each commit on the repository log page. Default
	value: "0".

enable-log-linecount::
	Flag which, when set to "1", will make cgit print the number of added
	and removed lines for each commit on the repository log page. Default
	value: "0".

enable-remote-branches::
	Flag which, when set to "1", will make cgit display remote branches
	in the summary and refs views. Default value: "0". See also:
	"repo.enable-remote-branches".

enable-stats::
	Flag which, when set to "1", enables the statistics page, with the
	language breakdown and the commits-per-author table. Default
	value: "0". See also: "repo.enable-stats", "max-stats".

enable-subject-links::
	Flag which, when set to "1", will make cgit use the subject of the
	parent commit as link text when generating links to parent commits
	in commit view. Default value: "0". See also:
	"repo.enable-subject-links".

enable-tree-linenumbers::
	Flag which, when set to "1", will make cgit generate linenumber links
	for plaintext blobs printed in the tree view. Default value: "1".

enable-tree-group-dirs::
	Flag which, when set to "1", makes the tree view list all directories
	first, sorted, followed by the files. When set to "0", entries appear
	in git's own order, with directories and files intermixed by name.
	Default value: "0".

favicon::
	Url used as link to the icon for cgit. Any path works, but keeping
	the value "/favicon.ico" is still worthwhile, since clients that do
	not parse the page head probe that path directly. Default value:
	"/favicon.ico".

footer::
	The content of the file specified with this option will be included
	verbatim at the bottom of all pages (i.e. it replaces the standard
	"generated by..." message. Default value: none.

head-include::
	The content of the file specified with this option will be included
	verbatim in the html HEAD section on all pages. Default value: none.

header::
	The content of the file specified with this option will be included
	verbatim at the top of all pages. Default value: none.

include::
	Name of a configfile to include before the rest of the current config-
	file is parsed. Default value: none. See also: "MACRO EXPANSION".

js::
	Url which specifies the javascript script document to include in all cgit
	pages.  Default value: "/cgit.js".  Setting this to an empty string will
	disable generation of the link to this file in the head section.

local-time::
	Flag which, if set to "1", makes cgit print commit and tag times in the
	servers timezone. Default value: "0".

logo::
	Url which specifies the source of an image which will be used as a logo
	on all cgit pages. Default value: "/cgit.png".

logo-link::
	Url loaded when clicking on the cgit logo image. If unspecified the
	calculated url of the repository index page will be used. Default
	value: none.

max-atom-items::
	Specifies the number of items to display in atom feeds view. Default
	value: "10".

max-blob-size::
	Specifies the maximum size in KBytes of a blob that cgit will read into
	memory to serve. It caps both the HTML blob view and the raw "plain" and
	"blob" output, and a larger object is refused rather than loaded whole.
	Default value: "10240" (10 MB). Set to "0" to disable the limit.

max-commit-count::
	Specifies the number of entries to list per page in "log" view. Default
	value: "50".

max-diff-files::
	If a commit changes more files than this, the "commit" and "diff"
	views show only the diffstat, where each file links to its own diff
	page. The "rawdiff" and "patch" views are never limited. Default
	value: "200". Set to "0" to always render every file inline.

max-diff-lines::
	If a single file's diff spans more lines than this, the whole-commit
	views print a note in its place linking to the file's own diff page,
	which always renders in full. Default value: "1000". Set to "0" to
	always render oversized files inline.

max-message-length::
	Specifies the maximum number of commit message characters to display in
	"log" view. Default value: "80".

max-patch-count::
	Specifies the maximum number of commits emitted as a series by the
	"patch" view when an explicit revision range is requested. A single
	commit is unaffected. Default value: "50". Set to "0" for no limit.

max-ref-count::
	Specifies the number of branches and tags to list per section on the
	"refs" view, and per page on the dedicated branch and tag pages that
	its overflow links lead to. Default value: "200". Set to "0" to list
	every ref on one page.

max-repo-count::
	Specifies the number of entries to list per page on the	repository
	index page. The value "0" shows all repositories without limitation.
	Default value: "50".

max-repodesc-length::
	Specifies the maximum number of repo description characters to display
	on the repository index page. Default value: "80".

max-stats::
	Bound the coarsest period selectable on the statistics page. Valid
	values are "week", "month", "quarter" and "year". Unset, every
	period is offered. This option no longer enables the page, that is
	what "enable-stats" does. Default value: none. See also:
	"enable-stats", "repo.max-stats".

mimetype.<ext>::
	Set the mimetype for the specified filename extension. This is used
	by the `plain` command when returning blob content.

mimetype-file::
	Specifies the file to use for automatic mimetype lookup. If specified
	then this field is used as a fallback when no "mimetype.<ext>" match is
	found. If unspecified then no such lookup is performed. The typical file
	to use on a Linux system is /etc/mime.types. The format of the file must
	comply to:
	- a comment line is an empty line or a line starting with a hash (#),
	  optionally preceded by whitespace
	- a non-comment line starts with the mimetype (like image/png), followed
	  by one or more file extensions (like jpg), all separated by whitespace
	Default value: none. See also: "mimetype.<ext>".

module-link::
	Text which will be used as the formatstring for a hyperlink when a
	submodule is printed in a directory listing. The arguments for the
	formatstring are the path and SHA1 of the submodule commit. Default
	value: none.

noplainemail::
	If set to "1" showing full author email addresses will be disabled.
	Default value: "0".

noheader::
	Flag which, when set to "1", will make cgit omit the standard header
	on all pages. Default value: none. See also: "embedded".

project-list::
	A list of subdirectories inside of scan-path, relative to it, that
	should loaded as git repositories. This must be defined prior to
	scan-path. Default value: none. See also: scan-path, "MACRO
	EXPANSION".

readme::
	Text which will be used as default value for "repo.readme". Multiple
	config keys may be specified, and cgit will use the first found file
	in this list. This is useful in conjunction with scan-path. Default
	value: none. See also: scan-path, repo.readme.

remove-suffix::
	If set to "1" and scan-path is enabled, if any repositories are found
	with a suffix of ".git", this suffix will be removed for the url and
	name. This must be defined prior to scan-path. Default value: "0".
	See also: scan-path.

renamelimit::
	Maximum number of files to consider when detecting renames. The value
	 "-1" uses the compiletime value in git (for further info, look at
	  `man git-diff`). Default value: "-1".

repository-sort::
	The way in which repositories in each section are sorted. Valid values
	are "name" for sorting by the repo name or "age" for sorting by the
	most recently updated repository. Default value: "name". See also:
	section, case-sensitive-sort, section-sort.

robots::
	Text used as content for the "robots" meta-tag. Default value:
	"index, nofollow".

root-desc::
	Text printed below the heading on the repository index page. Default
	value: "a fast webinterface for the git dscm".

root-readme::
	The content of the file specified with this option will be included
	verbatim below the "about" link on the repository index page. Default
	value: none.

root-title::
	Text printed as heading on the repository index page. Default value:
	"Git Repository Browser".

scan-hidden-path::
	If set to "1" and scan-path is enabled, scan-path will recurse into
	directories whose name starts with a period ('.'). Otherwise,
	scan-path will stay away from such directories (considered as
	"hidden"). Note that this does not apply to the ".git" directory in
	non-bare repos. This must be defined prior to scan-path.
	Default value: 0. See also: scan-path.

scan-path::
	A path which will be scanned for repositories. If caching is enabled,
	the result will be cached as a cgitrc include-file in the cache
	directory. If project-list has been defined prior to scan-path,
	scan-path loads only the directories listed in the file pointed to by
	project-list. Be advised that only the global settings taken
	before the scan-path directive will be applied to each repository.
	Default value: none. See also: cache-scanrc-ttl, project-list,
	"MACRO EXPANSION".

section::
	The name of the current repository section - all repositories defined
	after this option will inherit the current section name. Default value:
	none.

section-sort::
	Flag which, when set to "1", will sort the sections on the repository
	listing by name, along with the repositories within each section. Set
	this flag to "0" to preserve the order in the cgitrc file. Default
	value: "0". See also: section, case-sensitive-sort, repository-sort.

section-from-path::
	A number which, if defined prior to scan-path, specifies how many
	path elements from each repo path to use as a default section name.
	If negative, cgit will discard the specified number of path elements
	above the repo directory. Default value: "0".

side-by-side-diffs::
	If set to "1" shows side-by-side diffs instead of unidiffs per
	default. Default value: "0".

snapshots::
	Text which specifies the default set of snapshot formats that cgit
	generates links for. The value is a space-separated list of zero or
	more of the values "tar", "tar.gz", "tar.bz2", "tar.lz", "tar.xz",
	"tar.zst" and "zip". The special value "all" enables all snapshot
	formats. Default value: none.
	All compressors use default settings. Some settings can be influenced
	with environment variables, for example set ZSTD_CLEVEL=10 in web
	server environment for higher (but slower) zstd compression.

source-filter::
	Specifies a command which will be invoked to format plaintext blobs
	in the tree view. The command will get the blob content on its STDIN
	and the name of the blob as its only command line argument. The STDOUT
	from the command will be included verbatim as the blob contents, i.e.
	this can be used to implement e.g. syntax highlighting. When no
	source-filter is configured, cgit serves the text plain. A ready
	syntax highlighter using the Scintillua lexer collection ships as
	custom/extensions/syntax-highlight.lua, see the comments in that file for
	its dependencies. Default value: none. See also: "FILTER API".

summary-branches::
	Specifies the number of branches to display in the repository "summary"
	view. Default value: "10".

summary-log::
	Specifies the number of log entries to display in the repository
	"summary" view. Default value: "10".

summary-tags::
	Specifies the number of tags to display in the repository "summary"
	view. Default value: "10".

strict-export::
	Filename which, if specified, needs to be present within the repository
	for cgit to allow access to that repository. This can be used to emulate
	gitweb's EXPORT_OK and STRICT_EXPORT functionality and limit cgit's
	repositories to match those exported by git-daemon. This option must
	be defined prior to scan-path.

virtual-root::
	Url which, if specified, will be used as root for all cgit links. It
	will also cause cgit to generate 'virtual urls', i.e. urls like
	'/cgit/tree/README' as opposed to '?r=cgit&p=tree&path=README'. Default
	value: none.
	NOTE: cgit has recently learned how to use PATH_INFO to achieve the
	same kind of virtual urls, so this option will probably be deprecated.


REPOSITORY SETTINGS
-------------------
repo.about-filter::
	Override the default about-filter. Default value: none. See also:
	"enable-filter-overrides". See also: "FILTER API".

repo.branch-sort::
	Flag which, when set to "age", enables date ordering in the branch ref
	list, and when set to "name" enables ordering by branch name. Default
	value: "name".

repo.clone-url::
	A list of space-separated urls which can be used to clone this repo.
	Default value: none. See also: "MACRO EXPANSION".

repo.commit-filter::
	Override the default commit-filter. Default value: none. See also:
	"enable-filter-overrides". See also: "FILTER API".

repo.commit-sort::
	Flag which, when set to "date", enables strict date ordering in the
	commit log, and when set to "topo" enables strict topological
	ordering. If unset, the default ordering of "git log" is used. Default
	value: unset.

repo.defbranch::
	The name of the default branch for this repository. If no such branch
	exists in the repository, the first branch name (when sorted) is used
	as default instead. Default value: branch pointed to by HEAD, or
	"master" if there is no suitable HEAD.

repo.desc::
	The value to show as repository description. Default value: none.

repo.email-filter::
	Override the default email-filter. Default value: none. See also:
	"enable-filter-overrides". See also: "FILTER API".

repo.enable-blame::
	A flag which can be used to disable the global setting
	`enable-blame'. Default value: none.

repo.enable-commit-graph::
	A flag which can be used to disable the global setting
	`enable-commit-graph'. Default value: none.

repo.enable-follow-links::
	A flag which can be used to disable the global setting
	`enable-follow-links'. Default value: none.

repo.enable-html-serving::
	A flag which can be used to override the global setting
	`enable-html-serving`. Default value: none.

repo.enable-log-filecount::
	A flag which can be used to disable the global setting
	`enable-log-filecount'. Default value: none.

repo.enable-log-linecount::
	A flag which can be used to disable the global setting
	`enable-log-linecount'. Default value: none.

repo.enable-remote-branches::
	Flag which, when set to "1", will make cgit display remote branches
	in the summary and refs views. Default value: <enable-remote-branches>.

repo.enable-stats::
	A flag which can be used to override the global setting
	`enable-stats'. Default value: none.

repo.enable-subject-links::
	A flag which can be used to override the global setting
	`enable-subject-links'. Default value: none.

repo.extra-head-content::
	This value will be added verbatim to the head section of each page
	displayed for this repo. Default value: none.

repo.hide::
	Flag which, when set to "1", hides the repository from the repository
	index. The repository can still be accessed by providing a direct path.
	Default value: "0". See also: "repo.ignore".

repo.homepage::
	The value to show as repository homepage. Default value: none.

repo.ignore::
	Flag which, when set to "1", ignores the repository. The repository
	is not shown in the index and cannot be accessed by providing a direct
	path. Default value: "0". See also: "repo.hide".

repo.logo::
	Url which specifies the source of an image which will be used as a logo
	on this repo's pages. Default value: global logo.

repo.logo-link::
	Url loaded when clicking on the cgit logo image. If unspecified the
	calculated url of the repository index page will be used. Default
	value: global logo-link.

repo.module-link::
	Text which will be used as the formatstring for a hyperlink when a
	submodule is printed in a directory listing. The arguments for the
	formatstring are the path and SHA1 of the submodule commit. Default
	value: <module-link>

repo.module-link.<path>::
	Text which will be used as the formatstring for a hyperlink when a
	submodule with the specified subdirectory path is printed in a
	directory listing. The only argument for the formatstring is the SHA1
	of the submodule commit. Default value: none.

repo.max-stats::
	Override the default maximum statistics period. Valid values are equal
	to the values specified for the global "max-stats" setting. Default
	value: none.

repo.name::
	The value to show as repository name. Default value: <repo.url>.

repo.owner::
	A value used to identify the owner of the repository. Default value:
	none.

repo.path::
	An absolute path to the repository directory. For non-bare repositories
	this is the .git-directory. Default value: none.

repo.readme::
	A path (relative to <repo.path>) which specifies a file to include
	verbatim as the "About" page for this repo. You may also specify a
	git refspec by head or by hash by prepending the refspec followed by
	a colon. For example, "master:docs/readme.mkd". If the value begins
	with a colon, i.e. ":docs/readme.rst", the head giving in query or
	the default branch of the repository will be used. Sharing any file
	will expose that entire directory tree to the "/about/PATH" endpoints,
	so be sure that there are no non-public files located in the same
	directory as the readme file. Default value: <readme>.

repo.section::
	Override the current section name for this repository. Default value:
	none.

repo.snapshots::
	A mask of snapshot formats for this repo that cgit generates links for,
	restricted by the global "snapshots" setting. Default value:
	<snapshots>.

repo.snapshot-prefix::
	Prefix to use for snapshot links instead of the repository basename.
	For example, the "linux-stable" repository may wish to set this to
	"linux" so that snapshots are in the format "linux-3.15.4" instead
	of "linux-stable-3.15.4".  Default value: <empty> meaning to use
	the repository basename.

repo.source-filter::
	Override the default source-filter. Default value: none. See also:
	"enable-filter-overrides". See also: "FILTER API".

repo.url::
	The relative url used to access the repository. This must be the first
	setting specified for each repo. Default value: none.


REPOSITORY-SPECIFIC CGITRC FILE
-------------------------------
When the option "scan-path" is used to auto-discover git repositories, cgit
will try to parse the file "cgitrc" within any found repository. Such a
repo-specific config file may contain any of the repo-specific options
described above, except "repo.url" and "repo.path". Additionally, the "filter"
options are only acknowledged in repo-specific config files when
"enable-filter-overrides" is set to "1".

Note: the "repo." prefix is dropped from the option names in repo-specific
config files, e.g. "repo.desc" becomes "desc".


FILTER API
----------
By default, filters are separate processes that are executed each time they
are needed.  Alternative technologies may be used by prefixing the filter
specification with the relevant string; available values are:

'exec:'::
	The default "one process per filter" mode.

'lua:'::
	Executes the script using a built-in Lua interpreter. The script is
	loaded once per execution of cgit, and may be called multiple times
	during cgit's lifetime, making it a good choice for repeated filters
	such as the 'email filter'. It responds to three functions:

	'filter_open(argument1, argument2, argument3, ...)'::
		This is called upon activation of the filter for a particular
		set of data.
	'filter_write(buffer)'::
		This is called whenever cgit writes data to the webpage.
	'filter_close()'::
		This is called when the current filtering operation is
		completed. It must return an integer value. Usually 0
		indicates success.

	Additionally, cgit exposes to the Lua the following built-in functions:

	'html(str)'::
		Writes 'str' to the webpage.
	'html_txt(str)'::
		HTML escapes and writes 'str' to the webpage.
	'html_attr(str)'::
		HTML escapes for an attribute and writes "str' to the webpage.
	'html_url_path(str)'::
		URL escapes for a path and writes 'str' to the webpage.
	'html_url_arg(str)'::
		URL escapes for an argument and writes 'str' to the webpage.
	'html_include(file)'::
		Includes 'file' in webpage.


Parameters are provided to filters as follows.

about filter::
	This filter is given a single parameter: the filename of the source
	file to filter. The filter can use the filename to determine (for
	example) the type of syntax to follow when formatting the readme file.
	The about text that is to be filtered is available on standard input
	and the filtered text is expected on standard output.

auth filter::
	The authentication filter receives 12 parameters:
	  - filter action, explained below, which specifies which action the
	    filter is called for
	  - http cookie
	  - http method
	  - http referer
	  - http path
	  - http https flag
	  - cgit repo
	  - cgit page
	  - cgit url
	  - cgit login url
	When the filter action is "body", this filter must write to output the
	HTML for displaying the login form, which POSTs to the login url. When
	the filter action is "authenticate-cookie", this filter must validate
	the http cookie and return a 0 if it is invalid or 1 if it is valid,
	in the exit code / close function. If the filter action is
	"authenticate-post", this filter receives POST'd parameters on
	standard input, and should write a complete CGI response, preferably
	with a 302 redirect, and write to output one or more "Set-Cookie"
	HTTP headers, each followed by a newline.

	See `custom/extensions/auth-inline.lua` for a ready to modify example that
	keeps its user list inline, or `custom/extensions/auth-file.lua` for the
	same filter reading its users from files on disk.

commit filter::
	This filter is given no arguments. The commit message text that is to
	be filtered is available on standard input and the filtered text is
	expected on standard output.

email filter::
	This filter is given two parameters: the email address of the relevant
	author and a string indicating the originating page. The filter will
	then receive the text string to format on standard input and is
	expected to write to standard output the formatted text to be included
	in the page.

source filter::
	This filter is given a single parameter: the filename of the source
	file to filter. The filter can use the filename to determine (for
	example) the syntax highlighting mode. The contents of the source
	file that is to be filtered is available on standard input and the
	filtered contents is expected on standard output.


All filters are handed the following environment variables:

- CGIT_REPO_URL (from repo.url)
- CGIT_REPO_NAME (from repo.name)
- CGIT_REPO_PATH (from repo.path)
- CGIT_REPO_OWNER (from repo.owner)
- CGIT_REPO_DEFBRANCH (from repo.defbranch)
- CGIT_REPO_SECTION (from repo.section)
- CGIT_REPO_CLONE_URL (from repo.clone-url)

If a setting is not defined for a repository and the corresponding global
setting is also not defined (if applicable), then the corresponding
environment variable will be unset.


MACRO EXPANSION
---------------
The following cgitrc options support a simple macro expansion feature,
where tokens prefixed with "$" are replaced with the value of a similarly
named environment variable:

- cache-root
- include
- project-list
- scan-path

Macro expansion will also happen on the content of $CGIT_CONFIG, if
defined.

One usage of this feature is virtual hosting, which in its simplest form
can be accomplished by adding the following line to /etc/cgitrc:

	include=/etc/cgitrc.d/$HTTP_HOST

The following options are expanded during request processing, and support
the environment variables defined in "FILTER API":

- clone-url
- repo.clone-url


CACHE
-----

All cache ttl values are in minutes. Negative ttl values indicate that a page
type will never expire, and thus the first time a URL is accessed, the result
will be cached indefinitely, even if the underlying git repository changes.
Conversely, when a ttl value is zero, the cache is disabled for that
particular page type, and the page type is never cached.

SIGNATURES
----------

Cgit can host .asc signatures corresponding to various snapshot formats,
through use of git notes. For example, the following command may be used to
add a signature to a .tar.xz archive:

    git notes --ref=refs/notes/signatures/tar.xz add -C "$(
	gpg --output - --armor --detach-sign cgit-1.1.tar.xz |
	git hash-object -w --stdin
    )" v1.1

If it is instead desirable to attach a signature of the underlying .tar, this
will be linked, as a special case, beside a .tar.* link that does not have its
own signature. For example, a signature of a tarball of the latest tag might
be added with a similar command:

    tag="$(git describe --abbrev=0)"
    git notes --ref=refs/notes/signatures/tar add -C "$(
        git archive --format tar --prefix "cgit-${tag#v}/" "$tag" |
        gpg --output - --armor --detach-sign |
        git hash-object -w --stdin
    )" "$tag"

Since git-archive(1) is expected to produce stable output between versions,
this allows one to generate a long-term signature of the contents of a given
tag.


BUGS
----
Comments currently cannot appear on the same line as a setting; the comment
will be included as part of the value. E.g. this line:

	robots=index  # allow indexing

will generate the following html element:

	<meta name='robots' content='index  # allow indexing'/>



AUTHOR
------
Lars Hjemli <hjemli@gmail.com>
Jason A. Donenfeld <Jason@zx2c4.com>