gitweb/INSTALL - jrn/git - Git at Google

 GIT web Interface (gitweb) Installation
 =======================================

 First you have to generate gitweb.cgi from gitweb.perl using
 "make gitweb", then "make install-gitweb" appropriate files
 (gitweb.cgi, gitweb.js, gitweb.css, git-logo.png and git-favicon.png)
 to their destination. For example if git was (or is) installed with
 /usr prefix and gitwebdir is /var/www/cgi-bin, you can do

 	$ make prefix=/usr gitweb                            ;# as yourself
 	# make gitwebdir=/var/www/cgi-bin install-gitweb     ;# as root

 Alternatively you can use autoconf generated ./configure script to
 set up path to git binaries (via config.mak.autogen), so you can write
 instead

 	$ make configure                     ;# as yourself
 	$ ./configure --prefix=/usr          ;# as yourself
 	$ make gitweb                        ;# as yourself
 	# make gitwebdir=/var/www/cgi-bin \
 	       install-gitweb                ;# as root

 The above example assumes that your web server is configured to run
 [executable] files in /var/www/cgi-bin/ as server scripts (as CGI
 scripts).


 Requirements
 ------------

  - Core git tools
  - Perl 5.8
  - Perl modules: CGI, Encode, Fcntl, File::Find, File::Basename.
  - web server

 The following optional Perl modules are required for extra features
  - CGI::Fast and FCGI - for running gitweb as FastCGI script
  - HTML::TagCloud - for fancy tag cloud in project list view
  - HTTP::Date or Time::ParseDate - to support If-Modified-Since for feeds


 Build time configuration
 ------------------------

 See also "How to configure gitweb for your local system" section below.

 - There are many configuration variables which affect building of
   gitweb.cgi; see "default configuration for gitweb" section in main
   (top dir) Makefile, and instructions for building gitweb target.

   One of the most important is where to find the git wrapper binary. Gitweb
   tries to find the git wrapper at $(bindir)/git, so you have to set $bindir
   when building gitweb.cgi, or $prefix from which $bindir is derived. If
   you build and install gitweb together with the rest of the git suite,
   there should be no problems. Otherwise, if git was for example
   installed from a binary package, you have to set $prefix (or $bindir)
   accordingly.

 - Another important issue is where are git repositories you want to make
   available to gitweb. By default gitweb searches for repositories under
   /pub/git; if you want to have projects somewhere else, like /home/git,
   use GITWEB_PROJECTROOT build configuration variable.

   By default all git repositories under projectroot are visible and
   available to gitweb. The list of projects is generated by default by
   scanning the projectroot directory for git repositories. This can be
   changed (configured) as described in "Gitweb repositories" section
   below.

   Note that gitweb deals directly with the object database, and does not
   need a working directory; the name of the project is the name of its
   repository object database, usually projectname.git for bare
   repositories. If you want to provide gitweb access to non-bare (live)
   repositories, you can make projectname.git a symbolic link under
   projectroot linking to projectname/.git (but it is just
   a suggestion).

 - You can control where gitweb tries to find its main CSS style file,
   its JavaScript file, its favicon and logo with the GITWEB_CSS, GITWEB_JS
   GITWEB_FAVICON and GITWEB_LOGO build configuration variables. By default
   gitweb tries to find them in the same directory as gitweb.cgi script.

 - You can optionally generate minified versions of gitweb.js and gitweb.css
   by defining the JSMIN and CSSMIN build configuration variables. By default
   the non-minified versions will be used. NOTE: if you enable this option,
   substitute gitweb.min.js and gitweb.min.css for all uses of gitweb.js and
   gitweb.css in the help files.


 How to configure gitweb for your local system
 ---------------------------------------------

 You can specify the following configuration variables when building GIT:

  * GIT_BINDIR
    Points where to find the git executable.  You should set it up to
    the place where the git binary was installed (usually /usr/bin) if you
    don't install git from sources together with gitweb.  [Default: $(bindir)]
  * GITWEB_SITENAME
    Shown in the title of all generated pages, defaults to the server name
    (SERVER_NAME CGI environment variable) if not set. [No default]
  * GITWEB_PROJECTROOT
    The root directory for all projects shown by gitweb. Must be set
    correctly for gitweb to find repositories to display.  See also
    "Gitweb repositories" in the INSTALL file for gitweb.  [Default: /pub/git]
  * GITWEB_PROJECT_MAXDEPTH
    The filesystem traversing limit for getting the project list; the number
    is taken as depth relative to the projectroot.  It is used when
    GITWEB_LIST is a directory (or is not set; then project root is used).
    This is meant to speed up project listing on large work trees by limiting
    search depth.  [Default: 2007]
  * GITWEB_LIST
    Points to a directory to scan for projects (defaults to project root
    if not set / if empty) or to a file with explicit listing of projects
    (together with projects' ownership). See "Generating projects list
    using gitweb" in INSTALL file for gitweb to find out how to generate
    such file from scan of a directory. [No default, which means use root
    directory for projects]
  * GITWEB_EXPORT_OK
    Show repository only if this file exists (in repository).  Only
    effective if this variable evaluates to true.  [No default / Not set]
  * GITWEB_STRICT_EXPORT
    Only allow viewing of repositories also shown on the overview page.
    This for example makes GITWEB_EXPORT_OK to decide if repository is
    available and not only if it is shown.  If GITWEB_LIST points to
    file with list of project, only those repositories listed would be
    available for gitweb.  [No default]
  * GITWEB_HOMETEXT
    Points to an .html file which is included on the gitweb project
    overview page ('projects_list' view), if it exists.  Relative to
    gitweb.cgi script.  [Default: indextext.html]
  * GITWEB_SITE_HTML_HEAD_STRING
    html snippet to include in the <head> section of each page. [No default]
  * GITWEB_SITE_HEADER
    Filename of html text to include at top of each page.  Relative to
    gitweb.cgi script.  [No default]
  * GITWEB_SITE_FOOTER
    Filename of html text to include at bottom of each page.  Relative to
    gitweb.cgi script.  [No default]
  * GITWEB_HOME_LINK_STR
    String of the home link on top of all pages, leading to $home_link
    (usually main gitweb page, which means projects list).  Used as first
    part of gitweb view "breadcrumb trail": <home> / <project> / <view>.
    [Default: projects]
  * GITWEB_SITENAME
    Name of your site or organization to appear in page titles.  Set it
    to something descriptive for clearer bookmarks etc.  If not set
    (if empty) gitweb uses "$SERVER_NAME Git", or "Untitled Git" if
    SERVER_NAME CGI environment variable is not set (e.g. if running
    gitweb as standalone script).  [No default]
  * GITWEB_BASE_URL
    Git base URLs used for URL to where fetch project from, i.e. full
    URL is "$git_base_url/$project".  Shown on projects summary page.
    Repository URL for project can be also configured per repository; this
    takes precedence over URLs composed from base URL and a project name.
    Note that you can setup multiple base URLs (for example one for
    git:// protocol access, another for http:// access) from the gitweb
    config file.  [No default]
  * GITWEB_CSS
    Points to the location where you put gitweb.css on your web server
    (or to be more generic, the URI of gitweb stylesheet).  Relative to the
    base URI of gitweb.  Note that you can setup multiple stylesheets from
    the gitweb config file.  [Default: static/gitweb.css (or
    static/gitweb.min.css if the CSSMIN variable is defined / CSS minifier
    is used)]
  * GITWEB_JS
    Points to the location where you put gitweb.js on your web server
    (or to be more generic URI of JavaScript code used by gitweb).
    Relative to base URI of gitweb.  [Default: static/gitweb.js (or
    static/gitweb.min.js if JSMIN build variable is defined / JavaScript
    minifier is used)]
  * CSSMIN, JSMIN
    Invocation of a CSS minifier or a JavaScript minifier, respectively,
    working as a filter (source on standard input, minified result on
    standard output).  If set, it is used to generate a minified version of
    'static/gitweb.css' or 'static/gitweb.js', respectively.  *Note* that
    minified files would have *.min.css and *.min.js extension, which is
    important if you also set GITWEB_CSS and/or GITWEB_JS.  [No default]
  * GITWEB_LOGO
    Points to the location where you put git-logo.png on your web server
    (or to be more generic URI of logo, 72x27 size, displayed in top right
    corner of each gitweb page, and used as logo for Atom feed).  Relative
    to base URI of gitweb.  [Default: static/git-logo.png]
  * GITWEB_FAVICON
    Points to the location where you put git-favicon.png on your web server
    (or to be more generic URI of favicon, assumed to be image/png type;
    web browsers that support favicons (website icons) may display them
    in the browser's URL bar and next to site name in bookmarks).  Relative
    to base URI of gitweb.  [Default: static/git-favicon.png]
  * GITWEB_CONFIG
    This Perl file will be loaded using 'do' and can be used to override any
    of the options above as well as some other options -- see the "Runtime
    gitweb configuration" section below, and top of 'gitweb.cgi' for their
    full list and description.  If the environment variable GITWEB_CONFIG
    is set when gitweb.cgi is executed, then the file specified in the
    environment variable will be loaded instead of the file specified
    when gitweb.cgi was created.  [Default: gitweb_config.perl]
  * GITWEB_CONFIG_SYSTEM
    This Perl file will be loaded using 'do' as a fallback if GITWEB_CONFIG
    does not exist.  If the environment variable GITWEB_CONFIG_SYSTEM is set
    when gitweb.cgi is executed, then the file specified in the environment
    variable will be loaded instead of the file specified when gitweb.cgi was
    created.  [Default: /etc/gitweb.conf]
  * HIGHLIGHT_BIN
    Path to the highlight executable to use (must be the one from
    http://www.andre-simon.de due to assumptions about parameters and output).
    Useful if highlight is not installed on your webserver's PATH.
    [Default: highlight]

 Build example
 ~~~~~~~~~~~~~

 - To install gitweb to /var/www/cgi-bin/gitweb/, when git wrapper
   is installed at /usr/local/bin/git, the repositories (projects)
   we want to display are under /home/local/scm, and you do not use
   minifiers, you can do

 	make GITWEB_PROJECTROOT="/home/local/scm" \
 	     GITWEB_JS="gitweb/static/gitweb.js" \
 	     GITWEB_CSS="gitweb/static/gitweb.css" \
 	     GITWEB_LOGO="gitweb/static/git-logo.png" \
 	     GITWEB_FAVICON="gitweb/static/git-favicon.png" \
 	     bindir=/usr/local/bin \
 	     gitweb

 	make gitwebdir=/var/www/cgi-bin/gitweb install-gitweb


 Gitweb config file
 ------------------

 See also "Runtime gitweb configuration" section in README file
 for gitweb (in gitweb/README), and gitweb.conf(5) manpage.

 - You can configure gitweb further using the per-instance gitweb configuration file;
   by default this is a file named gitweb_config.perl in the same place as
   gitweb.cgi script. You can control the default place for the config file
   using the GITWEB_CONFIG build configuration variable, and you can set it
   using the GITWEB_CONFIG environment variable. If this file does not
   exist, gitweb looks for a system-wide configuration file, normally
   /etc/gitweb.conf. You can change the default using the
   GITWEB_CONFIG_SYSTEM build configuration variable, and override it
   through the GITWEB_CONFIG_SYSTEM environment variable.

   Note that the GITWEB_CONFIG_SYSTEM system-wide configuration file is
   only used for instances that lack per-instance configuration file.
   You can use GITWEB_CONFIG_COMMON common system-wide configuration
   file (normally /etc/gitweb-common.conf) to keep common default
   settings that apply to all instances.  Settings from per-instance or
   system-wide configuration file override those from common system-wide
   configuration file.

 - The gitweb config file is a fragment of perl code. You can set variables
   using "our $variable = value"; text from "#" character until the end
   of a line is ignored. See perlsyn(1) for details.

   See the top of gitweb.perl file for examples of customizable options.

 Config file example
 ~~~~~~~~~~~~~~~~~~~

 To enable blame, pickaxe search, and snapshot support, 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 to run at level 6 by
 adding the following lines to your $GITWEB_CONFIG:

 	$known_snapshot_formats{'zip'}{'disabled'} = 1;
 	$known_snapshot_formats{'tgz'}{'compressor'} = ['gzip','-6'];


 Gitweb repositories
 -------------------

 By default gitweb shows all git repositories under single common repository
 root on a local filesystem; see description of GITWEB_PROJECTROOT build-time
 configuration variable above (and also of GITWEB_LIST).

 More advanced usage, like limiting access or visibility of repositories and
 managing multiple roots are described on gitweb manpage.


 Example web server configuration
 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

 See also "Webserver configuration" and "Advanced web server setup" sections
 in gitweb(1) manpage.


 - Apache2, gitweb installed as CGI script,
   under /var/www/cgi-bin/

 	ScriptAlias /cgi-bin/ "/var/www/cgi-bin/"

 	<Directory "/var/www/cgi-bin">
 	    Options Indexes FollowSymlinks ExecCGI
 	    AllowOverride None
 	    Order allow,deny
 	    Allow from all
 	</Directory>

 - Apache2, gitweb installed as mod_perl legacy script,
   under /var/www/perl/

 	Alias /perl "/var/www/perl"

 	<Directory "/var/www/perl">
 	    SetHandler perl-script
 	    PerlResponseHandler ModPerl::Registry
 	    PerlOptions +ParseHeaders
 	    Options Indexes FollowSymlinks +ExecCGI
 	    AllowOverride None
 	    Order allow,deny
 	    Allow from all
 	</Directory>
	GIT web Interface (gitweb) Installation
	=======================================

	First you have to generate gitweb.cgi from gitweb.perl using
	"make gitweb", then "make install-gitweb" appropriate files
	(gitweb.cgi, gitweb.js, gitweb.css, git-logo.png and git-favicon.png)
	to their destination. For example if git was (or is) installed with
	/usr prefix and gitwebdir is /var/www/cgi-bin, you can do

	$ make prefix=/usr gitweb ;# as yourself
	# make gitwebdir=/var/www/cgi-bin install-gitweb ;# as root

	Alternatively you can use autoconf generated ./configure script to
	set up path to git binaries (via config.mak.autogen), so you can write
	instead

	$ make configure ;# as yourself
	$ ./configure --prefix=/usr ;# as yourself
	$ make gitweb ;# as yourself
	# make gitwebdir=/var/www/cgi-bin \
	install-gitweb ;# as root

	The above example assumes that your web server is configured to run
	[executable] files in /var/www/cgi-bin/ as server scripts (as CGI
	scripts).


	Requirements
	------------

	- Core git tools
	- Perl 5.8
	- Perl modules: CGI, Encode, Fcntl, File::Find, File::Basename.
	- web server

	The following optional Perl modules are required for extra features
	- CGI::Fast and FCGI - for running gitweb as FastCGI script
	- HTML::TagCloud - for fancy tag cloud in project list view
	- HTTP::Date or Time::ParseDate - to support If-Modified-Since for feeds


	Build time configuration
	------------------------

	See also "How to configure gitweb for your local system" section below.

	- There are many configuration variables which affect building of
	gitweb.cgi; see "default configuration for gitweb" section in main
	(top dir) Makefile, and instructions for building gitweb target.

	One of the most important is where to find the git wrapper binary. Gitweb
	tries to find the git wrapper at $(bindir)/git, so you have to set $bindir
	when building gitweb.cgi, or $prefix from which $bindir is derived. If
	you build and install gitweb together with the rest of the git suite,
	there should be no problems. Otherwise, if git was for example
	installed from a binary package, you have to set $prefix (or $bindir)
	accordingly.

	- Another important issue is where are git repositories you want to make
	available to gitweb. By default gitweb searches for repositories under
	/pub/git; if you want to have projects somewhere else, like /home/git,
	use GITWEB_PROJECTROOT build configuration variable.

	By default all git repositories under projectroot are visible and
	available to gitweb. The list of projects is generated by default by
	scanning the projectroot directory for git repositories. This can be
	changed (configured) as described in "Gitweb repositories" section
	below.

	Note that gitweb deals directly with the object database, and does not
	need a working directory; the name of the project is the name of its
	repository object database, usually projectname.git for bare
	repositories. If you want to provide gitweb access to non-bare (live)
	repositories, you can make projectname.git a symbolic link under
	projectroot linking to projectname/.git (but it is just
	a suggestion).

	- You can control where gitweb tries to find its main CSS style file,
	its JavaScript file, its favicon and logo with the GITWEB_CSS, GITWEB_JS
	GITWEB_FAVICON and GITWEB_LOGO build configuration variables. By default
	gitweb tries to find them in the same directory as gitweb.cgi script.

	- You can optionally generate minified versions of gitweb.js and gitweb.css
	by defining the JSMIN and CSSMIN build configuration variables. By default
	the non-minified versions will be used. NOTE: if you enable this option,
	substitute gitweb.min.js and gitweb.min.css for all uses of gitweb.js and
	gitweb.css in the help files.


	How to configure gitweb for your local system
	---------------------------------------------

	You can specify the following configuration variables when building GIT:

	* GIT_BINDIR
	Points where to find the git executable. You should set it up to
	the place where the git binary was installed (usually /usr/bin) if you
	don't install git from sources together with gitweb. [Default: $(bindir)]
	* GITWEB_SITENAME
	Shown in the title of all generated pages, defaults to the server name
	(SERVER_NAME CGI environment variable) if not set. [No default]
	* GITWEB_PROJECTROOT
	The root directory for all projects shown by gitweb. Must be set
	correctly for gitweb to find repositories to display. See also
	"Gitweb repositories" in the INSTALL file for gitweb. [Default: /pub/git]
	* GITWEB_PROJECT_MAXDEPTH
	The filesystem traversing limit for getting the project list; the number
	is taken as depth relative to the projectroot. It is used when
	GITWEB_LIST is a directory (or is not set; then project root is used).
	This is meant to speed up project listing on large work trees by limiting
	search depth. [Default: 2007]
	* GITWEB_LIST
	Points to a directory to scan for projects (defaults to project root
	if not set / if empty) or to a file with explicit listing of projects
	(together with projects' ownership). See "Generating projects list
	using gitweb" in INSTALL file for gitweb to find out how to generate
	such file from scan of a directory. [No default, which means use root
	directory for projects]
	* GITWEB_EXPORT_OK
	Show repository only if this file exists (in repository). Only
	effective if this variable evaluates to true. [No default / Not set]
	* GITWEB_STRICT_EXPORT
	Only allow viewing of repositories also shown on the overview page.
	This for example makes GITWEB_EXPORT_OK to decide if repository is
	available and not only if it is shown. If GITWEB_LIST points to
	file with list of project, only those repositories listed would be
	available for gitweb. [No default]
	* GITWEB_HOMETEXT
	Points to an .html file which is included on the gitweb project
	overview page ('projects_list' view), if it exists. Relative to
	gitweb.cgi script. [Default: indextext.html]
	* GITWEB_SITE_HTML_HEAD_STRING
	html snippet to include in the <head> section of each page. [No default]
	* GITWEB_SITE_HEADER
	Filename of html text to include at top of each page. Relative to
	gitweb.cgi script. [No default]
	* GITWEB_SITE_FOOTER
	Filename of html text to include at bottom of each page. Relative to
	gitweb.cgi script. [No default]
	* GITWEB_HOME_LINK_STR
	String of the home link on top of all pages, leading to $home_link
	(usually main gitweb page, which means projects list). Used as first
	part of gitweb view "breadcrumb trail": <home> / <project> / <view>.
	[Default: projects]
	* GITWEB_SITENAME
	Name of your site or organization to appear in page titles. Set it
	to something descriptive for clearer bookmarks etc. If not set
	(if empty) gitweb uses "$SERVER_NAME Git", or "Untitled Git" if
	SERVER_NAME CGI environment variable is not set (e.g. if running
	gitweb as standalone script). [No default]
	* GITWEB_BASE_URL
	Git base URLs used for URL to where fetch project from, i.e. full
	URL is "$git_base_url/$project". Shown on projects summary page.
	Repository URL for project can be also configured per repository; this
	takes precedence over URLs composed from base URL and a project name.
	Note that you can setup multiple base URLs (for example one for
	git:// protocol access, another for http:// access) from the gitweb
	config file. [No default]
	* GITWEB_CSS
	Points to the location where you put gitweb.css on your web server
	(or to be more generic, the URI of gitweb stylesheet). Relative to the
	base URI of gitweb. Note that you can setup multiple stylesheets from
	the gitweb config file. [Default: static/gitweb.css (or
	static/gitweb.min.css if the CSSMIN variable is defined / CSS minifier
	is used)]
	* GITWEB_JS
	Points to the location where you put gitweb.js on your web server
	(or to be more generic URI of JavaScript code used by gitweb).
	Relative to base URI of gitweb. [Default: static/gitweb.js (or
	static/gitweb.min.js if JSMIN build variable is defined / JavaScript
	minifier is used)]
	* CSSMIN, JSMIN
	Invocation of a CSS minifier or a JavaScript minifier, respectively,
	working as a filter (source on standard input, minified result on
	standard output). If set, it is used to generate a minified version of
	'static/gitweb.css' or 'static/gitweb.js', respectively. Note that
	minified files would have .min.css and .min.js extension, which is
	important if you also set GITWEB_CSS and/or GITWEB_JS. [No default]
	* GITWEB_LOGO
	Points to the location where you put git-logo.png on your web server
	(or to be more generic URI of logo, 72x27 size, displayed in top right
	corner of each gitweb page, and used as logo for Atom feed). Relative
	to base URI of gitweb. [Default: static/git-logo.png]
	* GITWEB_FAVICON
	Points to the location where you put git-favicon.png on your web server
	(or to be more generic URI of favicon, assumed to be image/png type;
	web browsers that support favicons (website icons) may display them
	in the browser's URL bar and next to site name in bookmarks). Relative
	to base URI of gitweb. [Default: static/git-favicon.png]
	* GITWEB_CONFIG
	This Perl file will be loaded using 'do' and can be used to override any
	of the options above as well as some other options -- see the "Runtime
	gitweb configuration" section below, and top of 'gitweb.cgi' for their
	full list and description. If the environment variable GITWEB_CONFIG
	is set when gitweb.cgi is executed, then the file specified in the
	environment variable will be loaded instead of the file specified
	when gitweb.cgi was created. [Default: gitweb_config.perl]
	* GITWEB_CONFIG_SYSTEM
	This Perl file will be loaded using 'do' as a fallback if GITWEB_CONFIG
	does not exist. If the environment variable GITWEB_CONFIG_SYSTEM is set
	when gitweb.cgi is executed, then the file specified in the environment
	variable will be loaded instead of the file specified when gitweb.cgi was
	created. [Default: /etc/gitweb.conf]
	* HIGHLIGHT_BIN
	Path to the highlight executable to use (must be the one from
	http://www.andre-simon.de due to assumptions about parameters and output).
	Useful if highlight is not installed on your webserver's PATH.
	[Default: highlight]

	Build example
	~~~~~~~~~~~~~

	- To install gitweb to /var/www/cgi-bin/gitweb/, when git wrapper
	is installed at /usr/local/bin/git, the repositories (projects)
	we want to display are under /home/local/scm, and you do not use
	minifiers, you can do

	make GITWEB_PROJECTROOT="/home/local/scm" \
	GITWEB_JS="gitweb/static/gitweb.js" \
	GITWEB_CSS="gitweb/static/gitweb.css" \
	GITWEB_LOGO="gitweb/static/git-logo.png" \
	GITWEB_FAVICON="gitweb/static/git-favicon.png" \
	bindir=/usr/local/bin \
	gitweb

	make gitwebdir=/var/www/cgi-bin/gitweb install-gitweb


	Gitweb config file
	------------------

	See also "Runtime gitweb configuration" section in README file
	for gitweb (in gitweb/README), and gitweb.conf(5) manpage.

	- You can configure gitweb further using the per-instance gitweb configuration file;
	by default this is a file named gitweb_config.perl in the same place as
	gitweb.cgi script. You can control the default place for the config file
	using the GITWEB_CONFIG build configuration variable, and you can set it
	using the GITWEB_CONFIG environment variable. If this file does not
	exist, gitweb looks for a system-wide configuration file, normally
	/etc/gitweb.conf. You can change the default using the
	GITWEB_CONFIG_SYSTEM build configuration variable, and override it
	through the GITWEB_CONFIG_SYSTEM environment variable.

	Note that the GITWEB_CONFIG_SYSTEM system-wide configuration file is
	only used for instances that lack per-instance configuration file.
	You can use GITWEB_CONFIG_COMMON common system-wide configuration
	file (normally /etc/gitweb-common.conf) to keep common default
	settings that apply to all instances. Settings from per-instance or
	system-wide configuration file override those from common system-wide
	configuration file.

	- The gitweb config file is a fragment of perl code. You can set variables
	using "our $variable = value"; text from "#" character until the end
	of a line is ignored. See perlsyn(1) for details.

	See the top of gitweb.perl file for examples of customizable options.

	Config file example
	~~~~~~~~~~~~~~~~~~~

	To enable blame, pickaxe search, and snapshot support, 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 to run at level 6 by
	adding the following lines to your $GITWEB_CONFIG:

	$known_snapshot_formats{'zip'}{'disabled'} = 1;
	$known_snapshot_formats{'tgz'}{'compressor'} = ['gzip','-6'];


	Gitweb repositories
	-------------------

	By default gitweb shows all git repositories under single common repository
	root on a local filesystem; see description of GITWEB_PROJECTROOT build-time
	configuration variable above (and also of GITWEB_LIST).

	More advanced usage, like limiting access or visibility of repositories and
	managing multiple roots are described on gitweb manpage.


	Example web server configuration
	~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

	See also "Webserver configuration" and "Advanced web server setup" sections
	in gitweb(1) manpage.


	- Apache2, gitweb installed as CGI script,
	under /var/www/cgi-bin/

	ScriptAlias /cgi-bin/ "/var/www/cgi-bin/"

	<Directory "/var/www/cgi-bin">
	Options Indexes FollowSymlinks ExecCGI
	AllowOverride None
	Order allow,deny
	Allow from all
	</Directory>

	- Apache2, gitweb installed as mod_perl legacy script,
	under /var/www/perl/

	Alias /perl "/var/www/perl"

	<Directory "/var/www/perl">
	SetHandler perl-script
	PerlResponseHandler ModPerl::Registry
	PerlOptions +ParseHeaders
	Options Indexes FollowSymlinks +ExecCGI
	AllowOverride None
	Order allow,deny
	Allow from all
	</Directory>