merge(third_party/git): Merge squashed git subtree at v2.23.0 r/373

Merge commit '1b593e1ea4d2af0f6444d9a7788d5d99abd6fde5' as 'third_party/git'

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+gitweb.conf(5)
+==============
+
+NAME
+----
+gitweb.conf - Gitweb (Git web interface) configuration file
+
+SYNOPSIS
+--------
+/etc/gitweb.conf, /etc/gitweb-common.conf, $GITWEBDIR/gitweb_config.perl
+
+DESCRIPTION
+-----------
+
+The gitweb CGI script for viewing Git repositories over the web uses a
+perl script fragment as its configuration file.  You can set variables
+using "`our $variable = value`"; text from a "#" character until the
+end of a line is ignored.  See *perlsyn*(1) for details.
+
+An example:
+
+------------------------------------------------
+# gitweb configuration file for http://git.example.org
+#
+our $projectroot = "/srv/git"; # FHS recommendation
+our $site_name = 'Example.org >> Repos';
+------------------------------------------------
+
+
+The configuration file is used to override the default settings that
+were built into gitweb at the time the 'gitweb.cgi' script was generated.
+
+While one could just alter the configuration settings in the gitweb
+CGI itself, those changes would be lost upon upgrade.  Configuration
+settings might also be placed into a file in the same directory as the
+CGI script with the default name 'gitweb_config.perl' -- allowing
+one to have multiple gitweb instances with different configurations by
+the use of symlinks.
+
+Note that some configuration can be controlled on per-repository rather than
+gitweb-wide basis: see "Per-repository gitweb configuration" subsection on
+linkgit:gitweb[1] manpage.
+
+
+DISCUSSION
+----------
+Gitweb reads configuration data from the following sources in the
+following order:
+
+ * built-in values (some set during build stage),
+
+ * common system-wide configuration file (defaults to
+   `/etc/gitweb-common.conf`),
+
+ * either per-instance configuration file (defaults to 'gitweb_config.perl'
+   in the same directory as the installed gitweb), or if it does not exists
+   then fallback system-wide configuration file (defaults to `/etc/gitweb.conf`).
+
+Values obtained in later configuration files override values obtained earlier
+in the above sequence.
+
+Locations of the common system-wide configuration file, the fallback
+system-wide configuration file and the per-instance configuration file
+are defined at compile time using build-time Makefile configuration
+variables, respectively `GITWEB_CONFIG_COMMON`, `GITWEB_CONFIG_SYSTEM`
+and `GITWEB_CONFIG`.
+
+You can also override locations of gitweb configuration files during
+runtime by setting the following environment variables:
+`GITWEB_CONFIG_COMMON`, `GITWEB_CONFIG_SYSTEM` and `GITWEB_CONFIG`
+to a non-empty value.
+
+
+The syntax of the configuration files is that of Perl, since these files are
+handled by sourcing them as fragments of Perl code (the language that
+gitweb itself is written in). Variables are typically set using the
+`our` qualifier (as in "`our $variable = <value>;`") to avoid syntax
+errors if a new version of gitweb no longer uses a variable and therefore
+stops declaring it.
+
+You can include other configuration file using read_config_file()
+subroutine.  For example, one might want to put gitweb configuration
+related to access control for viewing repositories via Gitolite (one
+of Git repository management tools) in a separate file, e.g. in
+`/etc/gitweb-gitolite.conf`.  To include it, put
+
+--------------------------------------------------
+read_config_file("/etc/gitweb-gitolite.conf");
+--------------------------------------------------
+
+somewhere in gitweb configuration file used, e.g. in per-installation
+gitweb configuration file.  Note that read_config_file() checks itself
+that the file it reads exists, and does nothing if it is not found.
+It also handles errors in included file.
+
+
+The default configuration with no configuration file at all may work
+perfectly well for some installations.  Still, a configuration file is
+useful for customizing or tweaking the behavior of gitweb in many ways, and
+some optional features will not be present unless explicitly enabled using
+the configurable `%features` variable (see also "Configuring gitweb
+features" section below).
+
+
+CONFIGURATION VARIABLES
+-----------------------
+Some configuration variables have their default values (embedded in the CGI
+script) set during building gitweb -- if that is the case, this fact is put
+in their description.  See gitweb's 'INSTALL' file for instructions on building
+and installing gitweb.
+
+
+Location of repositories
+~~~~~~~~~~~~~~~~~~~~~~~~
+The configuration variables described below control how gitweb finds
+Git repositories, and how repositories are displayed and accessed.
+
+See also "Repositories" and later subsections in linkgit:gitweb[1] manpage.
+
+$projectroot::
+	Absolute filesystem path which will be prepended to project path;
+	the path to repository is `$projectroot/$project`.  Set to
+	`$GITWEB_PROJECTROOT` during installation.  This variable has to be
+	set correctly for gitweb to find repositories.
++
+For example, if `$projectroot` is set to "/srv/git" by putting the following
+in gitweb config file:
++
+----------------------------------------------------------------------------
+our $projectroot = "/srv/git";
+----------------------------------------------------------------------------
++
+then
++
+------------------------------------------------
+http://git.example.com/gitweb.cgi?p=foo/bar.git
+------------------------------------------------
++
+and its path_info based equivalent
++
+------------------------------------------------
+http://git.example.com/gitweb.cgi/foo/bar.git
+------------------------------------------------
++
+will map to the path `/srv/git/foo/bar.git` on the filesystem.
+
+$projects_list::
+	Name of a plain text file listing projects, or a name of directory
+	to be scanned for projects.
++
+Project list files should list one project per line, with each line
+having the following format
++
+-----------------------------------------------------------------------------
+<URI-encoded filesystem path to repository> SP <URI-encoded repository owner>
+-----------------------------------------------------------------------------
++
+The default value of this variable is determined by the `GITWEB_LIST`
+makefile variable at installation time.  If this variable is empty, gitweb
+will fall back to scanning the `$projectroot` directory for repositories.
+
+$project_maxdepth::
+	If `$projects_list` variable is unset, gitweb will recursively
+	scan filesystem for Git repositories.  The `$project_maxdepth`
+	is used to limit traversing depth, relative to `$projectroot`
+	(starting point); it means that directories which are further
+	from `$projectroot` than `$project_maxdepth` will be skipped.
++
+It is purely performance optimization, originally intended for MacOS X,
+where recursive directory traversal is slow.  Gitweb follows symbolic
+links, but it detects cycles, ignoring any duplicate files and directories.
++
+The default value of this variable is determined by the build-time
+configuration variable `GITWEB_PROJECT_MAXDEPTH`, which defaults to
+2007.
+
+$export_ok::
+	Show repository only if this file exists (in repository).  Only
+	effective if this variable evaluates to true.  Can be set when
+	building gitweb by setting `GITWEB_EXPORT_OK`.  This path is
+	relative to `GIT_DIR`.  git-daemon[1] uses 'git-daemon-export-ok',
+	unless started with `--export-all`.  By default this variable is
+	not set, which means that this feature is turned off.
+
+$export_auth_hook::
+	Function used to determine which repositories should be shown.
+	This subroutine should take one parameter, the full path to
+	a project, and if it returns true, that project will be included
+	in the projects list and can be accessed through gitweb as long
+	as it fulfills the other requirements described by $export_ok,
+	$projects_list, and $projects_maxdepth.  Example:
++
+----------------------------------------------------------------------------
+our $export_auth_hook = sub { return -e "$_[0]/git-daemon-export-ok"; };
+----------------------------------------------------------------------------
++
+though the above might be done by using `$export_ok` instead
++
+----------------------------------------------------------------------------
+our $export_ok = "git-daemon-export-ok";
+----------------------------------------------------------------------------
++
+If not set (default), it means that this feature is disabled.
++
+See also more involved example in "Controlling access to Git repositories"
+subsection on linkgit:gitweb[1] manpage.
+
+$strict_export::
+	Only allow viewing of repositories also shown on the overview page.
+	This for example makes `$export_ok` file decide if repository is
+	available and not only if it is shown.  If `$projects_list` points to
+	file with list of project, only those repositories listed would be
+	available for gitweb.  Can be set during building gitweb via
+	`GITWEB_STRICT_EXPORT`.  By default this variable is not set, which
+	means that you can directly access those repositories that are hidden
+	from projects list page (e.g. the are not listed in the $projects_list
+	file).
+
+
+Finding files
+~~~~~~~~~~~~~
+The following configuration variables tell gitweb where to find files.
+The values of these variables are paths on the filesystem.
+
+$GIT::
+	Core git executable to use.  By default set to `$GIT_BINDIR/git`, which
+	in turn is by default set to `$(bindir)/git`.  If you use Git installed
+	from a binary package, you should usually set this to "/usr/bin/git".
+	This can just be "git" if your web server has a sensible PATH; from
+	security point of view it is better to use absolute path to git binary.
+	If you have multiple Git versions installed it can be used to choose
+	which one to use.  Must be (correctly) set for gitweb to be able to
+	work.
+
+$mimetypes_file::
+	File to use for (filename extension based) guessing of MIME types before
+	trying `/etc/mime.types`.  *NOTE* that this path, if relative, is taken
+	as relative to the current Git repository, not to CGI script.  If unset,
+	only `/etc/mime.types` is used (if present on filesystem).  If no mimetypes
+	file is found, mimetype guessing based on extension of file is disabled.
+	Unset by default.
+
+$highlight_bin::
+	Path to the highlight executable to use (it must be the one from
+	http://www.andre-simon.de[] due to assumptions about parameters and output).
+	By default set to 'highlight'; set it to full path to highlight
+	executable if it is not installed on your web server's PATH.
+	Note that 'highlight' feature must be set for gitweb to actually
+	use syntax highlighting.
++
+*NOTE*: for a file to be highlighted, its syntax type must be detected
+and that syntax must be supported by "highlight".  The default syntax
+detection is minimal, and there are many supported syntax types with no
+detection by default.  There are three options for adding syntax
+detection.  The first and second priority are `%highlight_basename` and
+`%highlight_ext`, which detect based on basename (the full filename, for
+example "Makefile") and extension (for example "sh").  The keys of these
+hashes are the basename and extension, respectively, and the value for a
+given key is the name of the syntax to be passed via `--syntax <syntax>`
+to "highlight".  The last priority is the "highlight" configuration of
+`Shebang` regular expressions to detect the language based on the first
+line in the file, (for example, matching the line "#!/bin/bash").  See
+the highlight documentation and the default config at
+/etc/highlight/filetypes.conf for more details.
++
+For example if repositories you are hosting use "phtml" extension for
+PHP files, and you want to have correct syntax-highlighting for those
+files, you can add the following to gitweb configuration:
++
+---------------------------------------------------------
+our %highlight_ext;
+$highlight_ext{'phtml'} = 'php';
+---------------------------------------------------------
+
+
+Links and their targets
+~~~~~~~~~~~~~~~~~~~~~~~
+The configuration variables described below configure some of gitweb links:
+their target and their look (text or image), and where to find page
+prerequisites (stylesheet, favicon, images, scripts).  Usually they are left
+at their default values, with the possible exception of `@stylesheets`
+variable.
+
+@stylesheets::
+	List of URIs of stylesheets (relative to the base URI of a page). You
+	might specify more than one stylesheet, for example to use "gitweb.css"
+	as base with site specific modifications in a separate stylesheet
+	to make it easier to upgrade gitweb.  For example, you can add
+	a `site` stylesheet by putting
++
+----------------------------------------------------------------------------
+push @stylesheets, "gitweb-site.css";
+----------------------------------------------------------------------------
++
+in the gitweb config file.  Those values that are relative paths are
+relative to base URI of gitweb.
++
+This list should contain the URI of gitweb's standard stylesheet.  The default
+URI of gitweb stylesheet can be set at build time using the `GITWEB_CSS`
+makefile variable.  Its default value is `static/gitweb.css`
+(or `static/gitweb.min.css` if the `CSSMIN` variable is defined,
+i.e. if CSS minifier is used during build).
++
+*Note*: there is also a legacy `$stylesheet` configuration variable, which was
+used by older gitweb.  If `$stylesheet` variable is defined, only CSS stylesheet
+given by this variable is used by gitweb.
+
+$logo::
+	Points to the location where you put 'git-logo.png' on your web
+	server, or to be more the generic URI of logo, 72x27 size).  This image
+	is displayed in the top right corner of each gitweb page and used as
+	a logo for the Atom feed.  Relative to the base URI of gitweb (as a path).
+	Can be adjusted when building gitweb using `GITWEB_LOGO` variable
+	By default set to `static/git-logo.png`.
+
+$favicon::
+	Points to the location where you put 'git-favicon.png' on your web
+	server, or to be more the generic URI of favicon, which will be served
+	as "image/png" type.  Web browsers that support favicons (website icons)
+	may display them in the browser's URL bar and next to the site name in
+	bookmarks.  Relative to the base URI of gitweb.  Can be adjusted at
+	build time using `GITWEB_FAVICON` variable.
+	By default set to `static/git-favicon.png`.
+
+$javascript::
+	Points to the location where you put 'gitweb.js' on your web server,
+	or to be more generic the URI of JavaScript code used by gitweb.
+	Relative to the base URI of gitweb.  Can be set at build time using
+	the `GITWEB_JS` build-time configuration variable.
++
+The default value is either `static/gitweb.js`, or `static/gitweb.min.js` if
+the `JSMIN` build variable was defined, i.e. if JavaScript minifier was used
+at build time.  *Note* that this single file is generated from multiple
+individual JavaScript "modules".
+
+$home_link::
+	Target of the home link on the top of all pages (the first part of view
+	"breadcrumbs").  By default it is set to the absolute URI of a current page
+	(to the value of `$my_uri` variable, or to "/" if `$my_uri` is undefined
+	or is an empty string).
+
+$home_link_str::
+	Label for the "home link" at the top of all pages, leading to `$home_link`
+	(usually the main gitweb page, which contains the projects list).  It is
+	used as the first component of gitweb's "breadcrumb trail":
+	`<home link> / <project> / <action>`.  Can be set at build time using
+	the `GITWEB_HOME_LINK_STR` variable.  By default it is set to "projects",
+	as this link leads to the list of projects.  Another popular choice is to
+	set it to the name of site.  Note that it is treated as raw HTML so it
+	should not be set from untrusted sources.
+
+@extra_breadcrumbs::
+	Additional links to be added to the start of the breadcrumb trail before
+	the home link, to pages that are logically "above" the gitweb projects
+	list, such as the organization and department which host the gitweb
+	server. Each element of the list is a reference to an array, in which
+	element 0 is the link text (equivalent to `$home_link_str`) and element
+	1 is the target URL (equivalent to `$home_link`).
++
+For example, the following setting produces a breadcrumb trail like
+"home / dev / projects / ..." where "projects" is the home link.
++
+----------------------------------------------------------------------------
+    our @extra_breadcrumbs = (
+      [ 'home' => 'https://www.example.org/' ],
+      [ 'dev'  => 'https://dev.example.org/' ],
+    );
+----------------------------------------------------------------------------
+
+$logo_url::
+$logo_label::
+	URI and label (title) for the Git logo link (or your site logo,
+	if you chose to use different logo image). By default, these both
+	refer to Git homepage, https://git-scm.com[]; in the past, they pointed
+	to Git documentation at https://www.kernel.org[].
+
+
+Changing gitweb's look
+~~~~~~~~~~~~~~~~~~~~~~
+You can adjust how pages generated by gitweb look using the variables described
+below.  You can change the site name, add common headers and footers for all
+pages, and add a description of this gitweb installation on its main page
+(which is the projects list page), etc.
+
+$site_name::
+	Name of your site or organization, to appear in page titles.  Set it
+	to something descriptive for clearer bookmarks etc.  If this variable
+	is not set or is, then gitweb uses the value of the `SERVER_NAME`
+	`CGI` environment variable, setting site name to "$SERVER_NAME Git",
+	or "Untitled Git" if this variable is not set (e.g. if running gitweb
+	as standalone script).
++
+Can be set using the `GITWEB_SITENAME` at build time.  Unset by default.
+
+$site_html_head_string::
+	HTML snippet to be included in the <head> section of each page.
+	Can be set using `GITWEB_SITE_HTML_HEAD_STRING` at build time.
+	No default value.
+
+$site_header::
+	Name of a file with HTML to be included at the top of each page.
+	Relative to the directory containing the 'gitweb.cgi' script.
+	Can be set using `GITWEB_SITE_HEADER` at build time.  No default
+	value.
+
+$site_footer::
+	Name of a file with HTML to be included at the bottom of each page.
+	Relative to the directory containing the 'gitweb.cgi' script.
+	Can be set using `GITWEB_SITE_FOOTER` at build time.  No default
+	value.
+
+$home_text::
+	Name of a HTML file which, if it exists, is included on the
+	gitweb projects overview page ("projects_list" view).  Relative to
+	the directory containing the gitweb.cgi script.  Default value
+	can be adjusted during build time using `GITWEB_HOMETEXT` variable.
+	By default set to 'indextext.html'.
+
+$projects_list_description_width::
+	The width (in characters) of the "Description" column of the projects list.
+	Longer descriptions will be truncated (trying to cut at word boundary);
+	the full description is available in the 'title' attribute (usually shown on
+	mouseover).  The default is 25, which might be too small if you
+	use long project descriptions.
+
+$default_projects_order::
+	Default value of ordering of projects on projects list page, which
+	means the ordering used if you don't explicitly sort projects list
+	(if there is no "o" CGI query parameter in the URL).  Valid values
+	are "none" (unsorted), "project" (projects are by project name,
+	i.e. path to repository relative to `$projectroot`), "descr"
+	(project description), "owner", and "age" (by date of most current
+	commit).
++
+Default value is "project".  Unknown value means unsorted.
+
+
+Changing gitweb's behavior
+~~~~~~~~~~~~~~~~~~~~~~~~~~
+These configuration variables control _internal_ gitweb behavior.
+
+$default_blob_plain_mimetype::
+	Default mimetype for the blob_plain (raw) view, if mimetype checking
+	doesn't result in some other type; by default "text/plain".
+	Gitweb guesses mimetype of a file to display based on extension
+	of its filename, using `$mimetypes_file` (if set and file exists)
+	and `/etc/mime.types` files (see *mime.types*(5) manpage; only
+	filename extension rules are supported by gitweb).
+
+$default_text_plain_charset::
+	Default charset for text files. If this is not set, the web server
+	configuration will be used.  Unset by default.
+
+$fallback_encoding::
+	Gitweb assumes this charset when a line contains non-UTF-8 characters.
+	The fallback decoding is used without error checking, so it can be even
+	"utf-8". The value must be a valid encoding; see the *Encoding::Supported*(3pm)
+	man page for a list. The default is "latin1", aka. "iso-8859-1".
+
+@diff_opts::
+	Rename detection options for git-diff and git-diff-tree. The default is
+	(\'-M'); set it to (\'-C') or (\'-C', \'-C') to also detect copies,
+	or set it to () i.e. empty list if you don't want to have renames
+	detection.
++
+*Note* that rename and especially copy detection can be quite
+CPU-intensive.  Note also that non Git tools can have problems with
+patches generated with options mentioned above, especially when they
+involve file copies (\'-C') or criss-cross renames (\'-B').
+
+
+Some optional features and policies
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+Most of features are configured via `%feature` hash; however some of extra
+gitweb features can be turned on and configured using variables described
+below.  This list beside configuration variables that control how gitweb
+looks does contain variables configuring administrative side of gitweb
+(e.g. cross-site scripting prevention; admittedly this as side effect
+affects how "summary" pages look like, or load limiting).
+
+@git_base_url_list::
+	List of Git base URLs.  These URLs are used to generate URLs
+	describing from where to fetch a project, which are shown on
+	project summary page.  The full fetch URL is "`$git_base_url/$project`",
+	for each element of this list. You can set up multiple base URLs
+	(for example one for `git://` protocol, and one for `http://`
+	protocol).
++
+Note that per repository configuration can be set in `$GIT_DIR/cloneurl`
+file, or as values of multi-value `gitweb.url` configuration variable in
+project config.  Per-repository configuration takes precedence over value
+composed from `@git_base_url_list` elements and project name.
++
+You can setup one single value (single entry/item in this list) at build
+time by setting the `GITWEB_BASE_URL` build-time configuration variable.
+By default it is set to (), i.e. an empty list.  This means that gitweb
+would not try to create project URL (to fetch) from project name.
+
+$projects_list_group_categories::
+	Whether to enable the grouping of projects by category on the project
+	list page. The category of a project is determined by the
+	`$GIT_DIR/category` file or the `gitweb.category` variable in each
+	repository's configuration.  Disabled by default (set to 0).
+
+$project_list_default_category::
+	Default category for projects for which none is specified.  If this is
+	set to the empty string, such projects will remain uncategorized and
+	listed at the top, above categorized projects.  Used only if project
+	categories are enabled, which means if `$projects_list_group_categories`
+	is true.  By default set to "" (empty string).
+
+$prevent_xss::
+	If true, some gitweb features are disabled to prevent content in
+	repositories from launching cross-site scripting (XSS) attacks.  Set this
+	to true if you don't trust the content of your repositories.
+	False by default (set to 0).
+
+$maxload::
+	Used to set the maximum load that we will still respond to gitweb queries.
+	If the server load exceeds this value then gitweb will return
+	"503 Service Unavailable" error.  The server load is taken to be 0
+	if gitweb cannot determine its value.  Currently it works only on Linux,
+	where it uses `/proc/loadavg`; the load there is the number of active
+	tasks on the system -- processes that are actually running -- averaged
+	over the last minute.
++
+Set `$maxload` to undefined value (`undef`) to turn this feature off.
+The default value is 300.
+
+$omit_age_column::
+	If true, omit the column with date of the most current commit on the
+	projects list page. It can save a bit of I/O and a fork per repository.
+
+$omit_owner::
+	If true prevents displaying information about repository owner.
+
+$per_request_config::
+	If this is set to code reference, it will be run once for each request.
+	You can set parts of configuration that change per session this way.
+	For example, one might use the following code in a gitweb configuration
+	file
++
+--------------------------------------------------------------------------------
+our $per_request_config = sub {
+	$ENV{GL_USER} = $cgi->remote_user || "gitweb";
+};
+--------------------------------------------------------------------------------
++
+If `$per_request_config` is not a code reference, it is interpreted as boolean
+value.  If it is true gitweb will process config files once per request,
+and if it is false gitweb will process config files only once, each time it
+is executed.  True by default (set to 1).
++
+*NOTE*: `$my_url`, `$my_uri`, and `$base_url` are overwritten with their default
+values before every request, so if you want to change them, be sure to set
+this variable to true or a code reference effecting the desired changes.
++
+This variable matters only when using persistent web environments that
+serve multiple requests using single gitweb instance, like mod_perl,
+FastCGI or Plackup.
+
+
+Other variables
+~~~~~~~~~~~~~~~
+Usually you should not need to change (adjust) any of configuration
+variables described below; they should be automatically set by gitweb to
+correct value.
+
+
+$version::
+	Gitweb version, set automatically when creating gitweb.cgi from
+	gitweb.perl. You might want to modify it if you are running modified
+	gitweb, for example
++
+---------------------------------------------------
+our $version .= " with caching";
+---------------------------------------------------
++
+if you run modified version of gitweb with caching support.  This variable
+is purely informational, used e.g. in the "generator" meta header in HTML
+header.
+
+$my_url::
+$my_uri::
+	Full URL and absolute URL of the gitweb script;
+	in earlier versions of gitweb you might have need to set those
+	variables, but now there should be no need to do it.  See
+	`$per_request_config` if you need to set them still.
+
+$base_url::
+	Base URL for relative URLs in pages generated by gitweb,
+	(e.g. `$logo`, `$favicon`, `@stylesheets` if they are relative URLs),
+	needed and used '<base href="$base_url">' only for URLs with nonempty
+	PATH_INFO.  Usually gitweb sets its value correctly,
+	and there is no need to set this variable, e.g. to $my_uri or "/".
+	See `$per_request_config` if you need to override it anyway.
+
+
+CONFIGURING GITWEB FEATURES
+---------------------------
+Many gitweb features can be enabled (or disabled) and configured using the
+`%feature` hash.  Names of gitweb features are keys of this hash.
+
+Each `%feature` hash element is a hash reference and has the following
+structure:
+----------------------------------------------------------------------
+"<feature_name>" => {
+	"sub" => <feature-sub (subroutine)>,
+	"override" => <allow-override (boolean)>,
+	"default" => [ <options>... ]
+},
+----------------------------------------------------------------------
+Some features cannot be overridden per project.  For those
+features the structure of appropriate `%feature` hash element has a simpler
+form:
+----------------------------------------------------------------------
+"<feature_name>" => {
+	"override" => 0,
+	"default" => [ <options>... ]
+},
+----------------------------------------------------------------------
+As one can see it lacks the \'sub' element.
+
+The meaning of each part of feature configuration is described
+below:
+
+default::
+	List (array reference) of feature parameters (if there are any),
+	used also to toggle (enable or disable) given feature.
++
+Note that it is currently *always* an array reference, even if
+feature doesn't accept any configuration parameters, and \'default'
+is used only to turn it on or off.  In such case you turn feature on
+by setting this element to `[1]`, and torn it off by setting it to
+`[0]`.  See also the passage about the "blame" feature in the "Examples"
+section.
++
+To disable features that accept parameters (are configurable), you
+need to set this element to empty list i.e. `[]`.
+
+override::
+	If this field has a true value then the given feature is
+	overridable, which means that it can be configured
+	(or enabled/disabled) on a per-repository basis.
++
+Usually given "<feature>" is configurable via the `gitweb.<feature>`
+config variable in the per-repository Git configuration file.
++
+*Note* that no feature is overridable by default.
+
+sub::
+	Internal detail of implementation.  What is important is that
+	if this field is not present then per-repository override for
+	given feature is not supported.
++
+You wouldn't need to ever change it in gitweb config file.
+
+
+Features in `%feature`
+~~~~~~~~~~~~~~~~~~~~~~
+The gitweb features that are configurable via `%feature` hash are listed
+below.  This should be a complete list, but ultimately the authoritative
+and complete list is in gitweb.cgi source code, with features described
+in the comments.
+
+blame::
+	Enable the "blame" and "blame_incremental" blob views, showing for
+	each line the last commit that modified it; see linkgit:git-blame[1].
+	This can be very CPU-intensive and is therefore disabled by default.
++
+This feature can be configured on a per-repository basis via
+repository's `gitweb.blame` configuration variable (boolean).
+
+snapshot::
+	Enable and configure the "snapshot" action, which allows user to
+	download a compressed archive of any tree or commit, as produced
+	by linkgit:git-archive[1] and possibly additionally compressed.
+	This can potentially generate high traffic if you have large project.
++
+The value of \'default' is a list of names of snapshot formats,
+defined in `%known_snapshot_formats` hash, that you wish to offer.
+Supported formats include "tgz", "tbz2", "txz" (gzip/bzip2/xz
+compressed tar archive) and "zip"; please consult gitweb sources for
+a definitive list.  By default only "tgz" is offered.
++
+This feature can be configured on a per-repository basis via
+repository's `gitweb.snapshot` configuration variable, which contains
+a comma separated list of formats or "none" to disable snapshots.
+Unknown values are ignored.
+
+grep::
+	Enable grep search, which lists the files in currently selected
+	tree (directory) containing the given string; see linkgit:git-grep[1].
+	This can be potentially CPU-intensive, of course.  Enabled by default.
++
+This feature can be configured on a per-repository basis via
+repository's `gitweb.grep` configuration variable (boolean).
+
+pickaxe::
+	Enable the so called pickaxe search, which will list the commits
+	that introduced or removed a given string in a file.  This can be
+	practical and quite faster alternative to "blame" action, but it is
+	still potentially CPU-intensive.  Enabled by default.
++
+The pickaxe search is described in linkgit:git-log[1] (the
+description of `-S<string>` option, which refers to pickaxe entry in
+linkgit:gitdiffcore[7] for more details).
++
+This feature can be configured on a per-repository basis by setting
+repository's `gitweb.pickaxe` configuration variable (boolean).
+
+show-sizes::
+	Enable showing size of blobs (ordinary files) in a "tree" view, in a
+	separate column, similar to what `ls -l` does; see description of
+	`-l` option in linkgit:git-ls-tree[1] manpage.  This costs a bit of
+	I/O.  Enabled by default.
++
+This feature can be configured on a per-repository basis via
+repository's `gitweb.showSizes` configuration variable (boolean).
+
+patches::
+	Enable and configure "patches" view, which displays list of commits in email
+	(plain text) output format; see also linkgit:git-format-patch[1].
+	The value is the maximum number of patches in a patchset generated
+	in "patches" view.  Set the 'default' field to a list containing single
+	item of or to an empty list to disable patch view, or to a list
+	containing a single negative number to remove any limit.
+	Default value is 16.
++
+This feature can be configured on a per-repository basis via
+repository's `gitweb.patches` configuration variable (integer).
+
+avatar::
+	Avatar support.  When this feature is enabled, views such as
+	"shortlog" or "commit" will display an avatar associated with
+	the email of each committer and author.
++
+Currently available providers are *"gravatar"* and *"picon"*.
+Only one provider at a time can be selected ('default' is one element list).
+If an unknown provider is specified, the feature is disabled.
+*Note* that some providers might require extra Perl packages to be
+installed; see `gitweb/INSTALL` for more details.
++
+This feature can be configured on a per-repository basis via
+repository's `gitweb.avatar` configuration variable.
++
+See also `%avatar_size` with pixel sizes for icons and avatars
+("default" is used for one-line like "log" and "shortlog", "double"
+is used for two-line like "commit", "commitdiff" or "tag").  If the
+default font sizes or lineheights are changed (e.g. via adding extra
+CSS stylesheet in `@stylesheets`), it may be appropriate to change
+these values.
+
+highlight::
+	Server-side syntax highlight support in "blob" view.  It requires
+	`$highlight_bin` program to be available (see the description of
+	this variable in the "Configuration variables" section above),
+	and therefore is disabled by default.
++
+This feature can be configured on a per-repository basis via
+repository's `gitweb.highlight` configuration variable (boolean).
+
+remote_heads::
+	Enable displaying remote heads (remote-tracking branches) in the "heads"
+	list.  In most cases the list of remote-tracking branches is an
+	unnecessary internal private detail, and this feature is therefore
+	disabled by default.  linkgit:git-instaweb[1], which is usually used
+	to browse local repositories, enables and uses this feature.
++
+This feature can be configured on a per-repository basis via
+repository's `gitweb.remote_heads` configuration variable (boolean).
+
+
+The remaining features cannot be overridden on a per project basis.
+
+search::
+	Enable text search, which will list the commits which match author,
+	committer or commit text to a given string; see the description of
+	`--author`, `--committer` and `--grep` options in linkgit:git-log[1]
+	manpage.  Enabled by default.
++
+Project specific override is not supported.
+
+forks::
+	If this feature is enabled, gitweb considers projects in
+	subdirectories of project root (basename) to be forks of existing
+	projects.  For each project +$projname.git+, projects in the
+	+$projname/+ directory and its subdirectories will not be
+	shown in the main projects list.  Instead, a \'\+' mark is shown
+	next to +$projname+, which links to a "forks" view that lists all
+	the forks (all projects in +$projname/+ subdirectory).  Additionally
+	a "forks" view for a project is linked from project summary page.
++
+If the project list is taken from a file (+$projects_list+ points to a
+file), forks are only recognized if they are listed after the main project
+in that file.
++
+Project specific override is not supported.
+
+actions::
+	Insert custom links to the action bar of all project pages.  This
+	allows you to link to third-party scripts integrating into gitweb.
++
+The "default" value consists of a list of triplets in the form
+`("<label>", "<link>", "<position>")` where "position" is the label
+after which to insert the link, "link" is a format string where `%n`
+expands to the project name, `%f` to the project path within the
+filesystem (i.e. "$projectroot/$project"), `%h` to the current hash
+(\'h' gitweb parameter) and `%b` to the current hash base
+(\'hb' gitweb parameter); `%%` expands to \'%'.
++
+For example, at the time this page was written, the http://repo.or.cz[]
+Git hosting site set it to the following to enable graphical log
+(using the third party tool *git-browser*):
++
+----------------------------------------------------------------------
+$feature{'actions'}{'default'} =
+	[ ('graphiclog', '/git-browser/by-commit.html?r=%n', 'summary')];
+----------------------------------------------------------------------
++
+This adds a link titled "graphiclog" after the "summary" link, leading to
+`git-browser` script, passing `r=<project>` as a query parameter.
++
+Project specific override is not supported.
+
+timed::
+	Enable displaying how much time and how many Git commands it took to
+	generate and display each page in the page footer (at the bottom of
+	page).  For example the footer might contain: "This page took 6.53325
+	seconds and 13 Git commands to generate."  Disabled by default.
++
+Project specific override is not supported.
+
+javascript-timezone::
+	Enable and configure the ability to change a common time zone for dates
+	in gitweb output via JavaScript.  Dates in gitweb output include
+	authordate and committerdate in "commit", "commitdiff" and "log"
+	views, and taggerdate in "tag" view.  Enabled by default.
++
+The value is a list of three values: a default time zone (for if the client
+hasn't selected some other time zone and saved it in a cookie), a name of cookie
+where to store selected time zone, and a CSS class used to mark up
+dates for manipulation.  If you want to turn this feature off, set "default"
+to empty list: `[]`.
++
+Typical gitweb config files will only change starting (default) time zone,
+and leave other elements at their default values:
++
+---------------------------------------------------------------------------
+$feature{'javascript-timezone'}{'default'}[0] = "utc";
+---------------------------------------------------------------------------
++
+The example configuration presented here is guaranteed to be backwards
+and forward compatible.
++
+Time zone values can be "local" (for local time zone that browser uses), "utc"
+(what gitweb uses when JavaScript or this feature is disabled), or numerical
+time zones in the form of "+/-HHMM", such as "+0200".
++
+Project specific override is not supported.
+
+extra-branch-refs::
+	List of additional directories under "refs" which are going to
+	be used as branch refs. For example if you have a gerrit setup
+	where all branches under refs/heads/ are official,
+	push-after-review ones and branches under refs/sandbox/,
+	refs/wip and refs/other are user ones where permissions are
+	much wider, then you might want to set this variable as
+	follows:
++
+--------------------------------------------------------------------------------
+$feature{'extra-branch-refs'}{'default'} =
+	['sandbox', 'wip', 'other'];
+--------------------------------------------------------------------------------
++
+This feature can be configured on per-repository basis after setting
+$feature{'extra-branch-refs'}{'override'} to true, via repository's
+`gitweb.extraBranchRefs` configuration variable, which contains a
+space separated list of refs. An example:
++
+--------------------------------------------------------------------------------
+[gitweb]
+	extraBranchRefs = sandbox wip other
+--------------------------------------------------------------------------------
++
+The gitweb.extraBranchRefs is actually a multi-valued configuration
+variable, so following example is also correct and the result is the
+same as of the snippet above:
++
+--------------------------------------------------------------------------------
+[gitweb]
+	extraBranchRefs = sandbox
+	extraBranchRefs = wip other
+--------------------------------------------------------------------------------
++
+It is an error to specify a ref that does not pass "git check-ref-format"
+scrutiny. Duplicated values are filtered.
+
+
+EXAMPLES
+--------
+
+To enable blame, pickaxe search, and snapshot support (allowing "tar.gz" and
+"zip" snapshots), while allowing individual projects to turn them off, put
+the following in your GITWEB_CONFIG file:
+
+--------------------------------------------------------------------------------
+$feature{'blame'}{'default'} = [1];
+$feature{'blame'}{'override'} = 1;
+
+$feature{'pickaxe'}{'default'} = [1];
+$feature{'pickaxe'}{'override'} = 1;
+
+$feature{'snapshot'}{'default'} = ['zip', 'tgz'];
+$feature{'snapshot'}{'override'} = 1;
+--------------------------------------------------------------------------------
+
+If you allow overriding for the snapshot feature, you can specify which
+snapshot formats are globally disabled. You can also add any command-line
+options you want (such as setting the compression level). For instance, you
+can disable Zip compressed snapshots and set *gzip*(1) to run at level 6 by
+adding the following lines to your gitweb configuration file:
+
+	$known_snapshot_formats{'zip'}{'disabled'} = 1;
+	$known_snapshot_formats{'tgz'}{'compressor'} = ['gzip','-6'];
+
+BUGS
+----
+Debugging would be easier if the fallback configuration file
+(`/etc/gitweb.conf`) and environment variable to override its location
+('GITWEB_CONFIG_SYSTEM') had names reflecting their "fallback" role.
+The current names are kept to avoid breaking working setups.
+
+ENVIRONMENT
+-----------
+The location of per-instance and system-wide configuration files can be
+overridden using the following environment variables:
+
+GITWEB_CONFIG::
+	Sets location of per-instance configuration file.
+GITWEB_CONFIG_SYSTEM::
+	Sets location of fallback system-wide configuration file.
+	This file is read only if per-instance one does not exist.
+GITWEB_CONFIG_COMMON::
+	Sets location of common system-wide configuration file.
+
+
+FILES
+-----
+gitweb_config.perl::
+	This is default name of per-instance configuration file.  The
+	format of this file is described above.
+/etc/gitweb.conf::
+	This is default name of fallback system-wide configuration
+	file.  This file is used only if per-instance configuration
+	variable is not found.
+/etc/gitweb-common.conf::
+	This is default name of common system-wide configuration
+	file.
+
+
+SEE ALSO
+--------
+linkgit:gitweb[1], linkgit:git-instaweb[1]
+
+'gitweb/README', 'gitweb/INSTALL'
+
+GIT
+---
+Part of the linkgit:git[1] suite