README


1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99

cgit - CGI for Git
==================

This is an attempt to create a fast web interface for the Git SCM, using a
built-in cache to decrease server I/O pressure.

Installation
------------

Building cgit involves building a proper version of Git. How to do this
depends on how you obtained the cgit sources:

a) If you're working in a cloned cgit repository, you first need to
initialize and update the Git submodule:

    $ git submodule init     # register the Git submodule in .git/config
    $ $EDITOR .git/config    # if you want to specify a different url for git
    $ git submodule update   # clone/fetch and checkout correct git version

b) If you're building from a cgit tarball, you can download a proper git
version like this:

    $ make get-git

When either a) or b) has been performed, you can build and install cgit like
this:

    $ make
    $ sudo make install

This will install `cgit.cgi` and `cgit.css` into `/var/www/htdocs/cgit`. You
can configure this location (and a few other things) by providing a `cgit.conf`
file (see the Makefile for details).

If you'd like to compile without Lua support, you may use:

    $ make NO_LUA=1

And if you'd like to specify a Lua implementation, you may use:

    $ make LUA_PKGCONFIG=lua5.1

If this is not specified, the Lua implementation will be auto-detected,
preferring LuaJIT if many are present. Acceptable values are generally "lua",
"luajit", "lua5.1", and "lua5.2".


Dependencies
------------

* libzip
* libcrypto (OpenSSL)
* libssl (OpenSSL)
* optional: luajit or lua, most reliably used when pkg-config is available

Apache configuration
--------------------

A new `Directory` section must probably be added for cgit, possibly something
like this:

    <Directory "/var/www/htdocs/cgit/">
        AllowOverride None
        Options +ExecCGI
        Order allow,deny
        Allow from all
    </Directory>


Runtime configuration
---------------------

The file `/etc/cgitrc` is read by cgit before handling a request. In addition
to runtime parameters, this file may also contain a list of repositories
displayed by cgit (see `cgitrc.5.txt` for further details).

The cache
---------

When cgit is invoked it looks for a cache file matching the request and
returns it to the client. If no such cache file exists (or if it has expired),
the content for the request is written into the proper cache file before the
file is returned.

If the cache file has expired but cgit is unable to obtain a lock for it, the
stale cache file is returned to the client. This is done to favour page
throughput over page freshness.

The generated content contains the complete response to the client, including
the HTTP headers `Modified` and `Expires`.

Online presence
---------------

* The cgit homepage is hosted by cgit at <http://git.zx2c4.com/cgit/about/>

* Patches, bug reports, discussions and support should go to the cgit
  mailing list: <cgit@lists.zx2c4.com>. To sign up, visit
  <http://lists.zx2c4.com/mailman/listinfo/cgit>
/* cgit.c: cgi for the git scm
 *
 * Copyright (C) 2006-2014 cgit Development Team <cgit@lists.zx2c4.com>
 *
 * Licensed under GNU General Public License v2
 *   (see COPYING for full license text)
 */

#include "cgit.h"
#include "cache.h"
#include "cmd.h"
#include "configfile.h"
#include "html.h"
#include "ui-shared.h"
#include "ui-stats.h"
#include "ui-blob.h"
#include "ui-summary.h"
#include "scan-tree.h"

const char *cgit_version = CGIT_VERSION;

static void add_mimetype(const char *name, const char *value)
{
	struct string_list_item *item;

	item = string_list_insert(&ctx.cfg.mimetypes, xstrdup(name));
	item->util = xstrdup(value);
}

static void process_cached_repolist(const char *path);

static void repo_config(struct cgit_repo *repo, const char *name, const char *value)
{
	struct string_list_item *item;

	if (!strcmp(name, "name"))
		repo->name = xstrdup(value);
	else if (!strcmp(name, "clone-url"))
		repo->clone_url = xstrdup(value);
	else if (!strcmp(name, "desc"))
		repo->desc = xstrdup(value);
	else if (!strcmp(name, "owner"))
		repo->owner = xstrdup(value);
	else if (!strcmp(name, "defbranch"))
		repo->defbranch = xstrdup(value);
	else if (!strcmp(name, "snapshots"))
		repo->snapshots = ctx.cfg.snapshots & cgit_parse_snapshots_mask(value);
	else if (!strcmp(name, "enable-commit-graph"))
		repo->enable_commit_graph = atoi(value);
	else if (!strcmp(name, "enable-log-filecount"))
		repo->enable_log_filecount = atoi(value);
	else if (!strcmp(name, "enable-log-linecount"))
		repo->enable_log_linecount = atoi(value);
	else if (!strcmp(name, "enable-remote-branches"))
		repo->enable_remote_branches = atoi(value);
	else if (!strcmp(name, "enable-subject-links"))
		repo->enable_subject_links = atoi(value);
	else if (!strcmp(name, "branch-sort")) {
		if (!strcmp(value, "age"))
			repo->branch_sort = 1;
		if (!strcmp(value, "name"))
			repo->branch_sort = 0;
	} else if (!strcmp(name, "commit-sort")) {
		if (!strcmp(value, "date"))
			repo->commit_sort = 1;
		if (!strcmp(value, "topo"))
			repo->commit_sort = 2;
	} else if (!strcmp(name, "max-stats"))
		repo->max_stats = cgit_find_stats_period(value, NULL);
	else if (!strcmp(name, "module-link"))
		repo->module_link= xstrdup(value);
	else if (starts_with(name, "module-link.")) {
		item = string_list_append(&repo->submodules, xstrdup(name + 12));
		item->util = xstrdup(value);
	} else if (!strcmp(name, "section"))
		repo->section = xstrdup(value);
	else if (!strcmp(name, "readme") && value != NULL) {
		if (repo->readme.items == ctx.cfg.readme.items)
			memset(&repo->readme, 0, sizeof(repo->readme));
		string_list_append(&repo->readme, xstrdup(value));
	} else if (!strcmp(name, "logo") && value != NULL)
		repo->logo = xstrdup(value);
	else if (!strcmp(name, "logo-link") && value != NULL)
		repo->logo_link = xstrdup(value);
	else if (ctx.cfg.enable_filter_overrides) {
		if (!strcmp(name, "about-filter"))
			repo->about_filter = cgit_new_filter(value, ABOUT);
		else if (!strcmp(name, "commit-filter"))
			repo->commit_filter = cgit_new_filter(value, COMMIT);
		else if (!strcmp(name, "source-filter"))
			repo->source_filter = cgit_new_filter(value, SOURCE);
		else if (!strcmp(name, "email-filter"))
			repo->email_filter = cgit_new_filter(value, EMAIL);
		else if (!strcmp(name, "owner-filter"))
			repo->owner_filter = cgit_new_filter(value, OWNER);
	} else if (!strcmp(name, "hide")) {
		repo->hide = atoi(value);
	} else if (!strcmp(name, "ignore")) {
		repo->ignore = atoi(value);
	}
}

static void config_cb(const char *name, const char *value)
{
	if (!strcmp(name, "section") || !strcmp(name, "repo.group"))
		ctx.cfg.section = xstrdup(value);
	else if (!strcmp(name, "repo.url"))
		ctx.repo = cgit_add_repo(value);
	else if (ctx.repo && !strcmp(name, "repo.path"))
		ctx.repo->path = trim_end(value, '/');
	else if (ctx.repo && starts_with(name, "repo."))
		repo_config(ctx.repo, name + 5, value);
	else if (!strcmp(name, "readme") && value != NULL)
		string_list_append(&ctx.cfg.readme, xstrdup(value));
	else if (!strcmp(name, "root-title"))
		ctx.cfg.root_title = xstrdup(value);
	else if (!strcmp(name, "root-desc"))
		ctx.cfg.root_desc = xstrdup(value);
	else if (!strcmp(name, "root-readme"))
		ctx.cfg.root_readme = xstrdup(value);
	else if (!strcmp(name, "css"))
		ctx.cfg.css = xstrdup(value);
	else if (!strcmp(name, "favicon"))
		ctx.cfg.favicon = xstrdup(value);
	else if (!strcmp(name, "footer"))
		ctx.cfg.footer = xstrdup(value);
	else if (!strcmp(name, "head-include"))
		ctx.cfg.head_include = xstrdup(value);
	else if (!strcmp(name, "header"))
		ctx.cfg.header = xstrdup(value);
	else if (!strcmp(name, "logo"))
		ctx.cfg.logo = xstrdup(value);
	else if (!strcmp(name, "index-header"))
		ctx.cfg.index_header = xstrdup(value);
	else if (!strcmp(name, "index-info"))
		ctx.cfg.index_info = xstrdup(value);
	else if (!strcmp(name, "logo-link"))
		ctx.cfg.logo_link = xstrdup(value);
	else if (!strcmp(name, "module-link"))
		ctx.cfg.module_link = xstrdup(value);
	else if (!strcmp(name, "strict-export"))
		ctx.cfg.strict_export = xstrdup(value);
	else if (!strcmp(name, "virtual-root")) {
		ctx.cfg.virtual_root = ensure_end(value, '/');
	} else if (!strcmp(name, "nocache"))
		ctx.cfg.nocache = atoi(value);
	else if (!strcmp(name, "noplainemail"))
		ctx.cfg.noplainemail = atoi(value);
	else if (!strcmp(name, "noheader"))
		ctx.cfg.noheader = atoi(value);
	else if (!strcmp(name, "snapshots"))
		ctx.cfg.snapshots = cgit_parse_snapshots_mask(value);
	else if (!strcmp(name, "enable-filter-overrides"))
		ctx.cfg.enable_filter_overrides = atoi(value);
	else if (!strcmp(name, "enable-http-clone"))
		ctx.cfg.enable_http_clone = atoi(value);
	else if (!strcmp(name, "enable-index-links"))
		ctx.cfg.enable_index_links = atoi(value);
	else if (!strcmp(name, "enable-index-owner"))
		ctx.cfg.enable_index_owner = atoi(value);
	else if (!strcmp(name, "enable-commit-graph"))
		ctx.cfg.enable_commit_graph = atoi(value);
	else if (!strcmp(name, "enable-log-filecount"))
		ctx.cfg.enable_log_filecount = atoi(value);
	else if (!strcmp(name, "enable-log-linecount"))
		ctx.cfg.enable_log_linecount = atoi(value);
	else if (!strcmp(name, "enable-remote-branches"))
		ctx.cfg.enable_remote_branches = atoi(value);
	else if (!strcmp(name, "enable-subject-links"))
		ctx.cfg.enable_subject_links = atoi(value);
	else if (!strcmp(name, "enable-tree-linenumbers"))
		ctx.cfg.enable_tree_linenumbers = atoi(value);
	else if (!strcmp(name, "enable-git-config"))
		ctx.cfg.enable_git_config = atoi(value);
	else if (!strcmp(name, "max-stats"))
		ctx.cfg.max_stats = cgit_find_stats_period(value, NULL);
	else if (!strcmp(name, "cache-size"))
		ctx.cfg.cache_size = atoi(value);
	else if (!strcmp(name, "cache-root"))
		ctx.cfg.cache_root = xstrdup(expand_macros(value));
	else if (!strcmp(name, "cache-root-ttl"))
		ctx.cfg.cache_root_ttl = atoi(value);
	else if (!strcmp(name, "cache-repo-ttl"))
		ctx.cfg.cache_repo_ttl = atoi(value);
	else if (!strcmp(name, "cache-scanrc-ttl"))
		ctx.cfg.cache_scanrc_ttl = atoi(value);
	else if (!strcmp(name, "cache-static-ttl"))
		ctx.cfg.cache_static_ttl = atoi(value);
	else if (!strcmp(name, "cache-dynamic-ttl"))
		ctx.cfg.cache_dynamic_ttl = atoi(value);
	else if (!strcmp(name, "cache-about-ttl"))
		ctx.cfg.cache_about_ttl = atoi(value);
	else if (!strcmp(name, "cache-snapshot-ttl"))
		ctx.cfg.cache_snapshot_ttl = atoi(value);
	else if (!strcmp(name, "case-sensitive-sort"))
		ctx.cfg.case_sensitive_sort = atoi(value);
	else if (!strcmp(name, "about-filter"))
		ctx.cfg.about_filter = cgit_new_filter(value, ABOUT);
	else if (!strcmp(name, "commit-filter"))
		ctx.cfg.commit_filter = cgit_new_filter(value, COMMIT);
	else if (!strcmp(name, "email-filter"))
		ctx.cfg.email_filter = cgit_new_filter(value, EMAIL);
	else if (!strcmp(name, "owner-filter"))
		ctx.cfg.owner_filter = cgit_new_filter(value, OWNER);
	else if (!strcmp(name, "auth-filter"))
		ctx.cfg.auth_filter = cgit_new_filter(value, AUTH);
	else if (!strcmp(name, "embedded"))
		ctx.cfg.embedded = atoi(value);
	else if (!strcmp(name, "max-atom-items"))
		ctx.cfg.max_atom_items = atoi(value);
	else if (!strcmp(name, "max-message-length"))
		ctx.cfg.max_msg_len = atoi(value);
	else if (!strcmp(name, "max-repodesc-length"))
		ctx.cfg.max_repodesc_len = atoi(value);
	else if (!strcmp(name, "max-blob-size"))
		ctx.cfg.max_blob_size = atoi(value);
	else if (!strcmp(name, "max-repo-count"))
		ctx.cfg.max_repo_count = atoi(value);
	else if (!strcmp(name, "max-commit-count"))
		ctx.cfg.max_commit_count = atoi(value);
	else if (!strcmp(name, "project-list"))
		ctx.cfg.project_list = xstrdup(expand_macros(value));
	else if (!strcmp(name, "scan-path"))
		if (!ctx.cfg.nocache && ctx.cfg.cache_size)
			process_cached_repolist(expand_macros(value));
		else if (ctx.cfg.project_list)
			scan_projects(expand_macros(value),
				      ctx.cfg.project_list, repo_config);
		else
			scan_tree(expand_macros(value), repo_config);
	else if (!strcmp(name, "scan-hidden-path"))
		ctx.cfg.scan_hidden_path = atoi(value);
	else if (!strcmp(name, "section-from-path"))
		ctx.cfg.section_from_path = atoi(value);
	else if (!strcmp(name, "repository-sort"))
		ctx.cfg.repository_sort = xstrdup(value);
	else if (!strcmp(name, "section-sort"))
		ctx.cfg.section_sort = atoi(value);
	else if (!strcmp(name, "source-filter"))
		ctx.cfg.source_filter = cgit_new_filter(value, SOURCE);
	else if (!strcmp(name, "summary-log"))
		ctx.cfg.summary_log = atoi(value);
	else if (!strcmp(name, "summary-branches"))
		ctx.cfg.summary_branches = atoi(value);
	else if (!strcmp(name, "summary-tags"))
		ctx.cfg.summary_tags = atoi(value);
	else if (!strcmp(name, "side-by-side-diffs"))
		ctx.cfg.difftype = atoi(value) ? DIFF_SSDIFF : DIFF_UNIFIED;
	else if (!strcmp(name, "agefile"))
		ctx.cfg.agefile = xstrdup(value);
	else if (!strcmp(name, "mimetype-file"))
		ctx.cfg.mimetype_file = xstrdup(value);
	else if (!strcmp(name, "renamelimit"))
		ctx.cfg.renamelimit = atoi(value);
	else if (!strcmp(name, "remove-suffix"))
		ctx.cfg.remove_suffix = atoi(value);
	else if (!strcmp(name, "robots"))
		ctx.cfg.robots = xstrdup(value);
	else if (!strcmp(name, "clone-prefix"))
		ctx.cfg.clone_prefix = xstrdup(value);
	else if (!strcmp(name, "clone-url"))
		ctx.cfg.clone_url = xstrdup(value);
	else if (!strcmp(name, "local-time"))
		ctx.cfg.local_time = atoi(value);
	else if (!strcmp(name, "commit-sort")) {
		if (!strcmp(value, "date"))
			ctx.cfg.commit_sort = 1;
		if (!strcmp(value, "topo"))
			ctx.cfg.commit_sort = 2;
	} else if (!strcmp(name, "branch-sort")) {
		if (!strcmp(value, "age"))
			ctx.cfg.branch_sort = 1;
		if (!strcmp(value, "name"))
			ctx.cfg.branch_sort = 0;
	} else if (starts_with(name, "mimetype."))
		add_mimetype(name + 9, value);
	else if (!strcmp(name, "include"))
		parse_configfile(expand_macros(value), config_cb);
}

static void querystring_cb(const char *name, const char *value)
{
	if (!value)
		value = "";

	if (!strcmp(name,"r")) {
		ctx.qry.repo = xstrdup(value);
		ctx.repo = cgit_get_repoinfo(value);
	} else if (!strcmp(name, "p")) {
		ctx.qry.page = xstrdup(value);
	} else if (!strcmp(name, "url")) {
		if (*value == '/')
			value++;
		ctx.qry.url = xstrdup(value);
		cgit_parse_url(value);
	} else if (!strcmp(name, "qt")) {
		ctx.qry.grep = xstrdup(value);
	} else if (!strcmp(name, "q")) {
		ctx.qry.search = xstrdup(value);
	} else if (!strcmp(name, "h")) {
		ctx.qry.head = xstrdup(value);
		ctx.qry.has_symref = 1;
	} else if (!strcmp(name, "id")) {
		ctx.qry.sha1 = xstrdup(value);
		ctx.qry.has_sha1 = 1;
	} else if (!strcmp(name, "id2")) {
		ctx.qry.sha2 = xstrdup(value);
		ctx.qry.has_sha1 = 1;
	} else if (!strcmp(name, "ofs")) {
		ctx.qry.ofs = atoi(value);
	} else if (!strcmp(name, "path")) {
		ctx.qry.path = trim_end(value, '/');
	} else if (!strcmp(name, "name")) {
		ctx.qry.name = xstrdup(value);
	} else if (!strcmp(name, "mimetype")) {
		ctx.qry.mimetype = xstrdup(value);
	} else if (!strcmp(name, "s")) {
		ctx.qry.sort = xstrdup(value);
	} else if (!strcmp(name, "showmsg")) {
		ctx.qry.showmsg = atoi(value);
	} else if (!strcmp(name, "period")) {
		ctx.qry.period = xstrdup(value);
	} else if (!strcmp(name, "dt")) {
		ctx.qry.difftype = atoi(value);
		ctx.qry.has_difftype = 1;
	} else if (!strcmp(name, "ss")) {
		/* No longer generated, but there may be links out there. */
		ctx.qry.difftype = atoi(value) ? DIFF_SSDIFF : DIFF_UNIFIED;
		ctx.qry.has_difftype = 1;
	} else if (!strcmp(name, "all")) {
		ctx.qry.show_all = atoi(value);
	} else if (!strcmp(name, "context")) {
		ctx.qry.context = atoi(value);
	} else if (!strcmp(name, "ignorews")) {
		ctx.qry.ignorews = atoi(value);
	}
}

static void prepare_context(void)
{
	memset(&ctx, 0, sizeof(ctx));
	ctx.cfg.agefile = "info/web/last-modified";
	ctx.cfg.nocache = 0;
	ctx.cfg.cache_size = 0;
	ctx.cfg.cache_max_create_time = 5;
	ctx.cfg.cache_root = CGIT_CACHE_ROOT;
	ctx.cfg.cache_about_ttl = 15;
	ctx.cfg.cache_snapshot_ttl = 5;
	ctx.cfg.cache_repo_ttl = 5;
	ctx.cfg.cache_root_ttl = 5;
	ctx.cfg.cache_scanrc_ttl = 15;
	ctx.cfg.cache_dynamic_ttl = 5;
	ctx.cfg.cache_static_ttl = -1;
	ctx.cfg.case_sensitive_sort = 1;
	ctx.cfg.branch_sort = 0;
	ctx.cfg.commit_sort = 0;
	ctx.cfg.css = "/cgit.css";
	ctx.cfg.logo = "/cgit.png";
	ctx.cfg.favicon = "/favicon.ico";
	ctx.cfg.local_time = 0;
	ctx.cfg.enable_http_clone = 1;
	ctx.cfg.enable_index_owner = 1;
	ctx.cfg.enable_tree_linenumbers = 1;
	ctx.cfg.enable_git_config = 0;
	ctx.cfg.max_repo_count = 50;
	ctx.cfg.max_commit_count = 50;
	ctx.cfg.max_lock_attempts = 5;
	ctx.cfg.max_msg_len = 80;
	ctx.cfg.max_repodesc_len = 80;
	ctx.cfg.max_blob_size = 0;
	ctx.cfg.max_stats = 0;
	ctx.cfg.project_list = NULL;
	ctx.cfg.renamelimit = -1;
	ctx.cfg.remove_suffix = 0;
	ctx.cfg.robots = "index, nofollow";
	ctx.cfg.root_title = "Git repository browser";
	ctx.cfg.root_desc = "a fast webinterface for the git dscm";
	ctx.cfg.scan_hidden_path = 0;
	ctx.cfg.script_name = CGIT_SCRIPT_NAME;
	ctx.cfg.section = "";
	ctx.cfg.repository_sort = "name";
	ctx.cfg.section_sort = 1;
	ctx.cfg.summary_branches = 10;
	ctx.cfg.summary_log = 10;
	ctx.cfg.summary_tags = 10;
	ctx.cfg.max_atom_items = 10;
	ctx.cfg.difftype = DIFF_UNIFIED;
	ctx.env.cgit_config = getenv("CGIT_CONFIG");
	ctx.env.http_host = getenv("HTTP_HOST");
	ctx.env.https = getenv("HTTPS");
	ctx.env.no_http = getenv("NO_HTTP");
	ctx.env.path_info = getenv("PATH_INFO");
	ctx.env.query_string = getenv("QUERY_STRING");
	ctx.env.request_method = getenv("REQUEST_METHOD");
	ctx.env.script_name = getenv("SCRIPT_NAME");
	ctx.env.server_name = getenv("SERVER_NAME");
	ctx.env.server_port = getenv("SERVER_PORT");
	ctx.env.http_cookie = getenv("HTTP_COOKIE");
	ctx.env.http_referer = getenv("HTTP_REFERER");
	ctx.env.content_length = getenv("CONTENT_LENGTH") ? strtoul(getenv("CONTENT_LENGTH"), NULL, 10) : 0;
	ctx.env.authenticated = 0;
	ctx.page.mimetype = "text/html";
	ctx.page.charset = PAGE_ENCODING;
	ctx.page.filename = NULL;
	ctx.page.size = 0;
	ctx.page.modified = time(NULL);
	ctx.page.expires = ctx.page.modified;
	ctx.page.etag = NULL;
	memset(&ctx.cfg.mimetypes, 0, sizeof(struct string_list));
	if (ctx.env.script_name)
		ctx.cfg.script_name = xstrdup(ctx.env.script_name);
	if (ctx.env.query_string)
		ctx.qry.raw = xstrdup(ctx.env.query_string);
	if (!ctx.env.cgit_config)
		ctx.env.cgit_config = CGIT_CONFIG;
}

struct refmatch {
	char *req_ref;
	char *first_ref;
	int match;
};

static int find_current_ref(const char *refname, const unsigned char *sha1,
			    int flags, void *cb_data)
{
	struct refmatch *info;

	info = (struct refmatch *)cb_data;
	if (!strcmp(refname, info->req_ref))
		info->match = 1;
	if (!info->first_ref)
		info->first_ref = xstrdup(refname);
	return info->match;
}

static void free_refmatch_inner(struct refmatch *info)
{
	if (info->first_ref)
		free(info->first_ref);
}

static char *find_default_branch(struct cgit_repo *repo)
{
	struct refmatch info;
	char *ref;

	info.req_ref = repo->defbranch;
	info.first_ref = NULL;
	info.match = 0;
	for_each_branch_ref(find_current_ref, &info);
	if (info.match)
		ref = info.req_ref;
	else
		ref = info.first_ref;
	if (ref)
		ref = xstrdup(ref);
	free_refmatch_inner(&info);

	return ref;
}

static char *guess_defbranch(void)
{
	const char *ref;
	unsigned char sha1[20];

	ref = resolve_ref_unsafe("HEAD", 0, sha1, NULL);
	if (!ref || !starts_with(ref, "refs/heads/"))
		return "master";
	return xstrdup(ref + 11);
}
/* The caller must free filename and ref after calling this. */
static inline void parse_readme(const char *readme, char **filename, char **ref, struct cgit_repo *repo)
{
	const char *colon;

	*filename = NULL;
	*ref = NULL;

	if (!readme || !readme[0])
		return;

	/* Check if the readme is tracked in the git repo. */
	colon = strchr(readme, ':');
	if (colon && strlen(colon) > 1) {
		/* If it starts with a colon, we want to use
		 * the default branch */
		if (colon == readme && repo->defbranch)
			*ref = xstrdup(repo->defbranch);
		else
			*ref = xstrndup(readme, colon - readme);
		readme = colon + 1;
	}

	/* Prepend repo path to relative readme path unless tracked. */
	if (!(*ref) && readme[0] != '/')
		*filename = fmtalloc("%s/%s", repo->path, readme);
	else
		*filename = xstrdup(readme);
}
static void choose_readme(struct cgit_repo *repo)
{
	int found;
	char *filename, *ref;
	struct string_list_item *entry;

	if (!repo->readme.nr)
		return;

	found = 0;
	for_each_string_list_item(entry, &repo->readme) {
		parse_readme(entry->string, &filename, &ref, repo);
		if (!filename) {
			free(filename);
			free(ref);
			continue;
		}
		if (ref) {
			if (cgit_ref_path_exists(filename, ref, 1)) {
				found = 1;
				break;
			}
		}
		else if (!access(filename, R_OK)) {
			found = 1;
			break;
		}
		free(filename);
		free(ref);
	}
	repo->readme.strdup_strings = 1;
	string_list_clear(&repo->readme, 0);
	repo->readme.strdup_strings = 0;
	if (found)
		string_list_append(&repo->readme, filename)->util = ref;
}

static void print_no_repo_clone_urls(const char *url)
{
        html("<tr><td><a rel='vcs-git' href='");
        html_url_path(url);
        html("' title='");
        html_attr(ctx.repo->name);
        html(" Git repository'>");
        html_txt(url);
        html("</a></td></tr>\n");
}

static int prepare_repo_cmd(void)
{
	unsigned char sha1[20];
	int nongit = 0;
	int rc;

	/* The path to the git repository. */
	setenv("GIT_DIR", ctx.repo->path, 1);

	/* Do not look in /etc/ for gitconfig and gitattributes. */
	setenv("GIT_CONFIG_NOSYSTEM", "1", 1);
	setenv("GIT_ATTR_NOSYSTEM", "1", 1);
	unsetenv("HOME");
	unsetenv("XDG_CONFIG_HOME");

	/* Setup the git directory and initialize the notes system. Both of these
	 * load local configuration from the git repository, so we do them both while
	 * the HOME variables are unset. */
	setup_git_directory_gently(&nongit);
	init_display_notes(NULL);

	if (nongit) {
		const char *name = ctx.repo->name;
		rc = errno;
		ctx.page.title = fmtalloc("%s - %s", ctx.cfg.root_title,
						"config error");
		ctx.repo = NULL;
		cgit_print_http_headers();
		cgit_print_docstart();
		cgit_print_pageheader();
		cgit_print_error("Failed to open %s: %s", name,
				 rc ? strerror(rc) : "Not a valid git repository");
		cgit_print_docend();
		return 1;
	}
	ctx.page.title = fmtalloc("%s - %s", ctx.repo->name, ctx.repo->desc);

	if (!ctx.repo->defbranch)
		ctx.repo->defbranch = guess_defbranch();

	if (!ctx.qry.head) {
		ctx.qry.nohead = 1;
		ctx.qry.head = find_default_branch(ctx.repo);
	}

	if (!ctx.qry.head) {
		cgit_print_http_headers();
		cgit_print_docstart();
		cgit_print_pageheader();
		cgit_print_error("Repository seems to be empty");
		if (!strcmp(ctx.qry.page, "summary")) {
			html("<table class='list'><tr class='nohover'><td>&nbsp;</td></tr><tr class='nohover'><th class='left'>Clone</th></tr>\n");
			cgit_prepare_repo_env(ctx.repo);
			cgit_add_clone_urls(print_no_repo_clone_urls);
			html("</table>\n");
		}
		cgit_print_docend();
		return 1;
	}

	if (get_sha1(ctx.qry.head, sha1)) {
		char *tmp = xstrdup(ctx.qry.head);
		ctx.qry.head = ctx.repo->defbranch;
		ctx.page.status = 404;
		ctx.page.statusmsg = "Not found";
		cgit_print_http_headers();
		cgit_print_docstart();
		cgit_print_pageheader();
		cgit_print_error("Invalid branch: %s", tmp);
		cgit_print_docend();
		free(tmp);
		return 1;
	}
	string_list_sort(&ctx.repo->submodules);
	cgit_prepare_repo_env(ctx.repo);
	choose_readme(ctx.repo);
	return 0;
}

static inline void open_auth_filter(const char *function)
{
	cgit_open_filter(ctx.cfg.auth_filter, function,
		ctx.env.http_cookie ? ctx.env.http_cookie : "",
		ctx.env.request_method ? ctx.env.request_method : "",
		ctx.env.query_string ? ctx.env.query_string : "",
		ctx.env.http_referer ? ctx.env.http_referer : "",
		ctx.env.path_info ? ctx.env.path_info : "",
		ctx.env.http_host ? ctx.env.http_host : "",
		ctx.env.https ? ctx.env.https : "",
		ctx.qry.repo ? ctx.qry.repo : "",
		ctx.qry.page ? ctx.qry.page : "",
		ctx.qry.url ? ctx.qry.url : "",
		cgit_loginurl());
}

/* We intentionally keep this rather small, instead of looping and
 * feeding it to the filter a couple bytes at a time. This way, the
 * filter itself does not need to handle any denial of service or
 * buffer bloat issues. If this winds up being too small, people
 * will complain on the mailing list, and we'll increase it as needed. */
#define MAX_AUTHENTICATION_POST_BYTES 4096
/* The filter is expected to spit out "Status: " and all headers. */
static inline void authenticate_post(void)
{
	char buffer[MAX_AUTHENTICATION_POST_BYTES];
	int len;

	open_auth_filter("authenticate-post");
	len = ctx.env.content_length;
	if (len > MAX_AUTHENTICATION_POST_BYTES)
		len = MAX_AUTHENTICATION_POST_BYTES;
	if (read(STDIN_FILENO, buffer, len) < 0)
		die_errno("Could not read POST from stdin");
	if (write(STDOUT_FILENO, buffer, len) < 0)
		die_errno("Could not write POST to stdout");
	cgit_close_filter(ctx.cfg.auth_filter);
	exit(0);
}

static inline void authenticate_cookie(void)
{
	/* If we don't have an auth_filter, consider all cookies valid, and thus return early. */
	if (!ctx.cfg.auth_filter) {
		ctx.env.authenticated = 1;
		return;
	}

	/* If we're having something POST'd to /login, we're authenticating POST,
	 * instead of the cookie, so call authenticate_post and bail out early.
	 * This pattern here should match /?p=login with POST. */
	if (ctx.env.request_method && ctx.qry.page && !ctx.repo && \
	    !strcmp(ctx.env.request_method, "POST") && !strcmp(ctx.qry.page, "login")) {
		authenticate_post();
		return;
	}

	/* If we've made it this far, we're authenticating the cookie for real, so do that. */
	open_auth_filter("authenticate-cookie");
	ctx.env.authenticated = cgit_close_filter(ctx.cfg.auth_filter);
}

static void process_request(void)
{
	struct cgit_cmd *cmd;

	/* If we're not yet authenticated, no matter what page we're on,
	 * display the authentication body from the auth_filter. This should
	 * never be cached. */
	if (!ctx.env.authenticated) {
		ctx.page.title = "Authentication Required";
		cgit_print_http_headers();
		cgit_print_docstart();
		cgit_print_pageheader();
		open_auth_filter("body");
		cgit_close_filter(ctx.cfg.auth_filter);
		cgit_print_docend();
		return;
	}

	cmd = cgit_get_cmd();
	if (!cmd) {
		ctx.page.title = "cgit error";
		ctx.page.status = 404;
		ctx.page.statusmsg = "Not found";
		cgit_print_http_headers();
		cgit_print_docstart();
		cgit_print_pageheader();
		cgit_print_error("Invalid request");
		cgit_print_docend();
		return;
	}

	if (!ctx.cfg.enable_http_clone && cmd->is_clone) {
		html_status(404, "Not found", 0);
		return;
	}

	/* If cmd->want_vpath is set, assume ctx.qry.path contains a "virtual"
	 * in-project path limit to be made available at ctx.qry.vpath.
	 * Otherwise, no path limit is in effect (ctx.qry.vpath = NULL).
	 */
	ctx.qry.vpath = cmd->want_vpath ? ctx.qry.path : NULL;

	if (cmd->want_repo && !ctx.repo) {
		cgit_print_http_headers();
		cgit_print_docstart();
		cgit_print_pageheader();
		cgit_print_error("No repository selected");
		cgit_print_docend();
		return;
	}

	if (ctx.repo && prepare_repo_cmd())
		return;

	if (cmd->want_layout) {
		cgit_print_http_headers();
		cgit_print_docstart();
		cgit_print_pageheader();
	}

	cmd->fn();

	if (cmd->want_layout)
		cgit_print_docend();
}

static int cmp_repos(const void *a, const void *b)
{
	const struct cgit_repo *ra = a, *rb = b;
	return strcmp(ra->url, rb->url);
}

static char *build_snapshot_setting(int bitmap)
{
	const struct cgit_snapshot_format *f;
	struct strbuf result = STRBUF_INIT;

	for (f = cgit_snapshot_formats; f->suffix; f++) {
		if (f->bit & bitmap) {
			if (result.len)
				strbuf_addch(&result, ' ');
			strbuf_addstr(&result, f->suffix);
		}
	}
	return strbuf_detach(&result, NULL);
}

static char *get_first_line(char *txt)
{
	char *t = xstrdup(txt);
	char *p = strchr(t, '\n');
	if (p)
		*p = '\0';
	return t;
}

static void print_repo(FILE *f, struct cgit_repo *repo)
{
	struct string_list_item *item;
	fprintf(f, "repo.url=%s\n", repo->url);
	fprintf(f, "repo.name=%s\n", repo->name);
	fprintf(f, "repo.path=%s\n", repo->path);
	if (repo->owner)
		fprintf(f, "repo.owner=%s\n", repo->owner);
	if (repo->desc) {
		char *tmp = get_first_line(repo->desc);
		fprintf(f, "repo.desc=%s\n", tmp);
		free(tmp);
	}
	for_each_string_list_item(item, &repo->readme) {
		if (item->util)
			fprintf(f, "repo.readme=%s:%s\n", (char *)item->util, item->string);
		else
			fprintf(f, "repo.readme=%s\n", item->string);
	}
	if (repo->defbranch)
		fprintf(f, "repo.defbranch=%s\n", repo->defbranch);
	if (repo->module_link)
		fprintf(f, "repo.module-link=%s\n", repo->module_link);
	if (repo->section)
		fprintf(f, "repo.section=%s\n", repo->section);
	if (repo->clone_url)
		fprintf(f, "repo.clone-url=%s\n", repo->clone_url);
	fprintf(f, "repo.enable-commit-graph=%d\n",
	        repo->enable_commit_graph);
	fprintf(f, "repo.enable-log-filecount=%d\n",
	        repo->enable_log_filecount);
	fprintf(f, "repo.enable-log-linecount=%d\n",
	        repo->enable_log_linecount);
	if (repo->about_filter && repo->about_filter != ctx.cfg.about_filter)
		cgit_fprintf_filter(repo->about_filter, f, "repo.about-filter=");
	if (repo->commit_filter && repo->commit_filter != ctx.cfg.commit_filter)
		cgit_fprintf_filter(repo->commit_filter, f, "repo.commit-filter=");
	if (repo->source_filter && repo->source_filter != ctx.cfg.source_filter)
		cgit_fprintf_filter(repo->source_filter, f, "repo.source-filter=");
	if (repo->email_filter && repo->email_filter != ctx.cfg.email_filter)
		cgit_fprintf_filter(repo->email_filter, f, "repo.email-filter=");
	if (repo->owner_filter && repo->owner_filter != ctx.cfg.owner_filter)
		cgit_fprintf_filter(repo->owner_filter, f, "repo.owner-filter=");
	if (repo->snapshots != ctx.cfg.snapshots) {
		char *tmp = build_snapshot_setting(repo->snapshots);
		fprintf(f, "repo.snapshots=%s\n", tmp ? tmp : "");
		free(tmp);
	}
	if (repo->max_stats != ctx.cfg.max_stats)
		fprintf(f, "repo.max-stats=%s\n",
		        cgit_find_stats_periodname(repo->max_stats));
	if (repo->logo)
		fprintf(f, "repo.logo=%s\n", repo->logo);
	if (repo->logo_link)
		fprintf(f, "repo.logo-link=%s\n", repo->logo_link);
	fprintf(f, "repo.enable-remote-branches=%d\n", repo->enable_remote_branches);
	fprintf(f, "repo.enable-subject-links=%d\n", repo->enable_subject_links);
	if (repo->branch_sort == 1)
		fprintf(f, "repo.branch-sort=age\n");
	if (repo->commit_sort) {
		if (repo->commit_sort == 1)
			fprintf(f, "repo.commit-sort=date\n");
		else if (repo->commit_sort == 2)
			fprintf(f, "repo.commit-sort=topo\n");
	}
	fprintf(f, "repo.hide=%d\n", repo->hide);
	fprintf(f, "repo.ignore=%d\n", repo->ignore);
	fprintf(f, "\n");
}

static void print_repolist(FILE *f, struct cgit_repolist *list, int start)
{
	int i;

	for (i = start; i < list->count; i++)
		print_repo(f, &list->repos[i]);
}

/* Scan 'path' for git repositories, save the resulting repolist in 'cached_rc'
 * and return 0 on success.
 */
static int generate_cached_repolist(const char *path, const char *cached_rc)
{
	struct strbuf locked_rc = STRBUF_INIT;
	int result = 0;
	int idx;
	FILE *f;

	strbuf_addf(&locked_rc, "%s.lock", cached_rc);
	f = fopen(locked_rc.buf, "wx");
	if (!f) {
		/* Inform about the error unless the lockfile already existed,
		 * since that only means we've got concurrent requests.
		 */
		result = errno;
		if (result != EEXIST)
			fprintf(stderr, "[cgit] Error opening %s: %s (%d)\n",
				locked_rc.buf, strerror(result), result);
		goto out;
	}
	idx = cgit_repolist.count;
	if (ctx.cfg.project_list)
		scan_projects(path, ctx.cfg.project_list, repo_config);
	else
		scan_tree(path, repo_config);
	print_repolist(f, &cgit_repolist, idx);
	if (rename(locked_rc.buf, cached_rc))
		fprintf(stderr, "[cgit] Error renaming %s to %s: %s (%d)\n",
			locked_rc.buf, cached_rc, strerror(errno), errno);
	fclose(f);
out:
	strbuf_release(&locked_rc);
	return result;
}

static void process_cached_repolist(const char *path)
{
	struct stat st;
	struct strbuf cached_rc = STRBUF_INIT;
	time_t age;
	unsigned long hash;

	hash = hash_str(path);
	if (ctx.cfg.project_list)
		hash += hash_str(ctx.cfg.project_list);
	strbuf_addf(&cached_rc, "%s/rc-%8lx", ctx.cfg.cache_root, hash);

	if (stat(cached_rc.buf, &st)) {
		/* Nothing is cached, we need to scan without forking. And
		 * if we fail to generate a cached repolist, we need to
		 * invoke scan_tree manually.
		 */
		if (generate_cached_repolist(path, cached_rc.buf)) {
			if (ctx.cfg.project_list)
				scan_projects(path, ctx.cfg.project_list,
					      repo_config);
			else
				scan_tree(path, repo_config);
		}
		goto out;
	}

	parse_configfile(cached_rc.buf, config_cb);

	/* If the cached configfile hasn't expired, lets exit now */
	age = time(NULL) - st.st_mtime;
	if (age <= (ctx.cfg.cache_scanrc_ttl * 60))
		goto out;

	/* The cached repolist has been parsed, but it was old. So lets
	 * rescan the specified path and generate a new cached repolist
	 * in a child-process to avoid latency for the current request.
	 */
	if (fork())
		goto out;

	exit(generate_cached_repolist(path, cached_rc.buf));
out:
	strbuf_release(&cached_rc);
}

static void cgit_parse_args(int argc, const char **argv)
{
	int i;
	int scan = 0;

	for (i = 1; i < argc; i++) {
		if (!strcmp(argv[i], "--version")) {
			printf("CGit %s | http://git.zx2c4.com/cgit/\n\nCompiled in features:\n", CGIT_VERSION);
#ifdef NO_LUA
			printf("[-] ");
#else
			printf("[+] ");
#endif
			printf("Lua scripting\n");
#ifndef HAVE_LINUX_SENDFILE
			printf("[-] ");
#else
			printf("[+] ");
#endif
			printf("Linux sendfile() usage\n");

			exit(0);
		}
		if (starts_with(argv[i], "--cache=")) {
			ctx.cfg.cache_root = xstrdup(argv[i] + 8);
		} else if (!strcmp(argv[i], "--nocache")) {
			ctx.cfg.nocache = 1;
		} else if (!strcmp(argv[i], "--nohttp")) {
			ctx.env.no_http = "1";
		} else if (starts_with(argv[i], "--query=")) {
			ctx.qry.raw = xstrdup(argv[i] + 8);
		} else if (starts_with(argv[i], "--repo=")) {
			ctx.qry.repo = xstrdup(argv[i] + 7);
		} else if (starts_with(argv[i], "--page=")) {
			ctx.qry.page = xstrdup(argv[i] + 7);
		} else if (starts_with(argv[i], "--head=")) {
			ctx.qry.head = xstrdup(argv[i] + 7);
			ctx.qry.has_symref = 1;
		} else if (starts_with(argv[i], "--sha1=")) {
			ctx.qry.sha1 = xstrdup(argv[i] + 7);
			ctx.qry.has_sha1 = 1;
		} else if (starts_with(argv[i], "--ofs=")) {
			ctx.qry.ofs = atoi(argv[i] + 6);
		} else if (starts_with(argv[i], "--scan-tree=") ||
		           starts_with(argv[i], "--scan-path=")) {
			/*
			 * HACK: The global snapshot bit mask defines the set
			 * of allowed snapshot formats, but the config file
			 * hasn't been parsed yet so the mask is currently 0.
			 * By setting all bits high before scanning we make
			 * sure that any in-repo cgitrc snapshot setting is
			 * respected by scan_tree().
			 *
			 * NOTE: We assume that there aren't more than 8
			 * different snapshot formats supported by cgit...
			 */
			ctx.cfg.snapshots = 0xFF;
			scan++;
			scan_tree(argv[i] + 12, repo_config);
		}
	}
	if (scan) {
		qsort(cgit_repolist.repos, cgit_repolist.count,
			sizeof(struct cgit_repo), cmp_repos);
		print_repolist(stdout, &cgit_repolist, 0);
		exit(0);
	}
}

static int calc_ttl(void)
{
	if (!ctx.repo)
		return ctx.cfg.cache_root_ttl;

	if (!ctx.qry.page)
		return ctx.cfg.cache_repo_ttl;

	if (!strcmp(ctx.qry.page, "about"))
		return ctx.cfg.cache_about_ttl;

	if (!strcmp(ctx.qry.page, "snapshot"))
		return ctx.cfg.cache_snapshot_ttl;

	if (ctx.qry.has_sha1)
		return ctx.cfg.cache_static_ttl;

	if (ctx.qry.has_symref)
		return ctx.cfg.cache_dynamic_ttl;

	return ctx.cfg.cache_repo_ttl;
}

int main(int argc, const char **argv)
{
	const char *path;
	int err, ttl;

	cgit_init_filters();
	atexit(cgit_cleanup_filters);

	prepare_context();
	cgit_repolist.length = 0;
	cgit_repolist.count = 0;
	cgit_repolist.repos = NULL;

	cgit_parse_args(argc, argv);
	parse_configfile(expand_macros(ctx.env.cgit_config), config_cb);
	ctx.repo = NULL;
	http_parse_querystring(ctx.qry.raw, querystring_cb);

	/* If virtual-root isn't specified in cgitrc, lets pretend
	 * that virtual-root equals SCRIPT_NAME, minus any possibly
	 * trailing slashes.
	 */
	if (!ctx.cfg.virtual_root && ctx.cfg.script_name)
		ctx.cfg.virtual_root = ensure_end(ctx.cfg.script_name, '/');

	/* If no url parameter is specified on the querystring, lets
	 * use PATH_INFO as url. This allows cgit to work with virtual
	 * urls without the need for rewriterules in the webserver (as
	 * long as PATH_INFO is included in the cache lookup key).
	 */
	path = ctx.env.path_info;
	if (!ctx.qry.url && path) {
		if (path[0] == '/')
			path++;
		ctx.qry.url = xstrdup(path);
		if (ctx.qry.raw) {
			char *newqry = fmtalloc("%s?%s", path, ctx.qry.raw);
			free(ctx.qry.raw);
			ctx.qry.raw = newqry;
		} else
			ctx.qry.raw = xstrdup(ctx.qry.url);
		cgit_parse_url(ctx.qry.url);
	}

	/* Before we go any further, we set ctx.env.authenticated by checking to see
	 * if the supplied cookie is valid. All cookies are valid if there is no
	 * auth_filter. If there is an auth_filter, the filter decides. */
	authenticate_cookie();

	ttl = calc_ttl();
	if (ttl < 0)
		ctx.page.expires += 10 * 365 * 24 * 60 * 60; /* 10 years */
	else
		ctx.page.expires += ttl * 60;
	if (!ctx.env.authenticated || (ctx.env.request_method && !strcmp(ctx.env.request_method, "HEAD")))
		ctx.cfg.nocache = 1;
	if (ctx.cfg.nocache)
		ctx.cfg.cache_size = 0;
	err = cache_process(ctx.cfg.cache_size, ctx.cfg.cache_root,
			    ctx.qry.raw, ttl, process_request);
	cgit_cleanup_filters();
	if (err)
		cgit_print_error("Error processing page: %s (%d)",
				 strerror(err), err);
	return err;
}