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pre { line-height: 125%; }
td.linenos .normal { color: inherit; background-color: transparent; padding-left: 5px; padding-right: 5px; }
span.linenos { color: inherit; background-color: transparent; padding-left: 5px; padding-right: 5px; }
td.linenos .special { color: #000000; background-color: #ffffc0; padding-left: 5px; padding-right: 5px; }
span.linenos.special { color: #000000; background-color: #ffffc0; padding-left: 5px; padding-right: 5px; }
.highlight .hll { background-color: #ffffcc }
.highlight .c { color: #888888 } /* Comment */
.highlight .err { color: #a61717; background-color: #e3d2d2 } /* Error */
.highlight .k { color: #008800; font-weight: bold } /* Keyword */
.highlight .ch { color: #888888 } /* Comment.Hashbang */
.highlight .cm { color: #888888 } /* Comment.Multiline */
.highlight .cp { color: #cc0000; font-weight: bold } /* Comment.Preproc */
.highlight .cpf { color: #888888 } /* Comment.PreprocFile */
.highlight .c1 { color: #888888 } /* Comment.Single */
.highlight .cs { color: #cc0000; font-weight: bold; background-color: #fff0f0 } /* Comment.Special */
.highlight .gd { color: #000000; background-color: #ffdddd } /* Generic.Deleted */
.highlight .ge { font-style: italic } /* Generic.Emph */
.highlight .gr { color: #aa0000 } /* Generic.Error */
.highlight .gh { color: #333333 } /* Generic.Heading */
.highlight .gi { color: #000000; background-color: #ddffdd } /* Generic.Inserted */
.highlight .go { color: #888888 } /* Generic.Output */
.highlight .gp { color: #555555 } /* Generic.Prompt */
.highlight .gs { font-weight: bold } /* Generic.Strong */
.highlight .gu { color: #666666 } /* Generic.Subheading */
.highlight .gt { color: #aa0000 } /* Generic.Traceback */
.highlight .kc { color: #008800; font-weight: bold } /* Keyword.Constant */
.highlight .kd { color: #008800; font-weight: bold } /* Keyword.Declaration */
.highlight .kn { color: #008800; font-weight: bold } /* Keyword.Namespace */
.highlight .kp { color: #008800 } /* Keyword.Pseudo */
.highlight .kr { color: #008800; font-weight: bold } /* Keyword.Reserved */
.highlight .kt { color: #888888; font-weight: bold } /* Keyword.Type */
.highlight .m { color: #0000DD; font-weight: bold } /* Literal.Number */
.highlight .s { color: #dd2200; background-color: #fff0f0 } /* Literal.String */
.highlight .na { color: #336699 } /* Name.Attribute */
.highlight .nb { color: #003388 } /* Name.Builtin */
.highlight .nc { color: #bb0066; font-weight: bold } /* Name.Class */
.highlight .no { color: #003366; font-weight: bold } /* Name.Constant */
.highlight .nd { color: #555555 } /* Name.Decorator */
.highlight .ne { color: #bb0066; font-weight: bold } /* Name.Exception */
.highlight .nf { color: #0066bb; font-weight: bold } /* Name.Function */
.highlight .nl { color: #336699; font-style: italic } /* Name.Label */
.highlight .nn { color: #bb0066; font-weight: bold } /* Name.Namespace */
.highlight .py { color: #336699; font-weight: bold } /* Name.Property */
.highlight .nt { color: #bb0066; font-weight: bold } /* Name.Tag */
.highlight .nv { color: #336699 } /* Name.Variable */
.highlight .ow { color: #008800 } /* Operator.Word */
.highlight .w { color: #bbbbbb } /* Text.Whitespace */
.highlight .mb { color: #0000DD; font-weight: bold } /* Literal.Number.Bin */
.highlight .mf { color: #0000DD; font-weight: bold } /* Literal.Number.Float */
.highlight .mh { color: #0000DD; font-weight: bold } /* Literal.Number.Hex */
.highlight .mi { color: #0000DD; font-weight: bold } /* Literal.Number.Integer */
.highlight .mo { color: #0000DD; font-weight: bold } /* Literal.Number.Oct */
.highlight .sa { color: #dd2200; background-color: #fff0f0 } /* Literal.String.Affix */
.highlight .sb { color: #dd2200; background-color: #fff0f0 } /* Literal.String.Backtick */
.highlight .sc { color: #dd2200; background-color: #fff0f0 } /* Literal.String.Char */
.highlight .dl { color: #dd2200; background-color: #fff0f0 } /* Literal.String.Delimiter */
.highlight .sd { color: #dd2200; background-color: #fff0f0 } /* Literal.String.Doc */
.highlight .s2 { color: #dd2200; background-color: #fff0f0 } /* Literal.String.Double */
.highlight .se { color: #0044dd; background-color: #fff0f0 } /* Literal.String.Escape */
.highlight .sh { color: #dd2200; background-color: #fff0f0 } /* Literal.String.Heredoc */
.highlight .si { color: #3333bb; background-color: #fff0f0 } /* Literal.String.Interpol */
.highlight .sx { color: #22bb22; background-color: #f0fff0 } /* Literal.String.Other */
.highlight .sr { color: #008800; background-color: #fff0ff } /* Literal.String.Regex */
.highlight .s1 { color: #dd2200; background-color: #fff0f0 } /* Literal.String.Single */
.highlight .ss { color: #aa6600; background-color: #fff0f0 } /* Literal.String.Symbol */
.highlight .bp { color: #003388 } /* Name.Builtin.Pseudo */
.highlight .fm { color: #0066bb; font-weight: bold } /* Name.Function.Magic */
.highlight .vc { color: #336699 } /* Name.Variable.Class */
.highlight .vg { color: #dd7700 } /* Name.Variable.Global */
.highlight .vi { color: #3333bb } /* Name.Variable.Instance */
.highlight .vm { color: #336699 } /* Name.Variable.Magic */
.highlight .il { color: #0000DD; font-weight: bold } /* Literal.Number.Integer.Long */
                       cgit - cgi for git


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


Dependencies:
  -git 1.5.3
  -zip lib
  -crypto lib
  -openssl lib


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 also contains a list of the repositories
displayed by cgit.

A template cgitrc is shipped with the sources, and all parameters and default
values are documented in this file.


The cache

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

If the cachefile has expired but cgit is unable to obtain a lock for it, the
stale cachefile 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".


The missing features

* Submodule links in the directory listing page have a fixed format per
  repository. This should probably be extended to a generic map between
  submodule path and url.

* Branch- and tag-lists in the summary page can get very long, they should
  probably only show something like the ten "latest modified" branches and
  a similar number of "most recent" tags.

* There should be a new page for browsing refs/heads and refs/tags, with links
  from the summary page whenever the branch/tag lists overflow.

* The log-page should have more/better search options (author, committer,
  pickaxe, paths) and possibly support arbitrary revision specifiers.

* A set of test-scripts is required before cgit-1.0 can be released.

Patches/bugreports/suggestions/comments are always welcome, please feel free
to contact the author: hjemli@gmail.com
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/* shared.c: global vars + some callback functions
 *
 * Copyright (C) 2006 Lars Hjemli
 *
 * Licensed under GNU General Public License v2
 *   (see COPYING for full license text)
 */

#include "cgit.h"
#include <stdio.h>

struct cgit_repolist cgit_repolist;
struct cgit_context ctx;

int chk_zero(int result, char *msg)
{
	if (result != 0)
		die("%s: %s", msg, strerror(errno));
	return result;
}

int chk_positive(int result, char *msg)
{
	if (result <= 0)
		die("%s: %s", msg, strerror(errno));
	return result;
}

int chk_non_negative(int result, char *msg)
{
    	if (result < 0)
	    	die("%s: %s",msg, strerror(errno));
	return result;
}

struct cgit_repo *cgit_add_repo(const char *url)
{
	struct cgit_repo *ret;

	if (++cgit_repolist.count > cgit_repolist.length) {
		if (cgit_repolist.length == 0)
			cgit_repolist.length = 8;
		else
			cgit_repolist.length *= 2;
		cgit_repolist.repos = xrealloc(cgit_repolist.repos,
					       cgit_repolist.length *
					       sizeof(struct cgit_repo));
	}

	ret = &cgit_repolist.repos[cgit_repolist.count-1];
	memset(ret, 0, sizeof(struct cgit_repo));
	ret->url = trim_end(url, '/');
	ret->name = ret->url;
	ret->path = NULL;
	ret->desc = "[no description]";
	ret->owner = NULL;
	ret->section = ctx.cfg.section;
	ret->snapshots = ctx.cfg.snapshots;
	ret->enable_commit_graph = ctx.cfg.enable_commit_graph;
	ret->enable_log_filecount = ctx.cfg.enable_log_filecount;
	ret->enable_log_linecount = ctx.cfg.enable_log_linecount;
	ret->enable_remote_branches = ctx.cfg.enable_remote_branches;
	ret->enable_subject_links = ctx.cfg.enable_subject_links;
	ret->max_stats = ctx.cfg.max_stats;
	ret->module_link = ctx.cfg.module_link;
	ret->readme = ctx.cfg.readme;
	ret->mtime = -1;
	ret->about_filter = ctx.cfg.about_filter;
	ret->commit_filter = ctx.cfg.commit_filter;
	ret->source_filter = ctx.cfg.source_filter;
	ret->clone_url = ctx.cfg.clone_url;
	ret->submodules.strdup_strings = 1;
	return ret;
}

struct cgit_repo *cgit_get_repoinfo(const char *url)
{
	int i;
	struct cgit_repo *repo;

	for (i=0; i<cgit_repolist.count; i++) {
		repo = &cgit_repolist.repos[i];
		if (!strcmp(repo->url, url))
			return repo;
	}
	return NULL;
}

void *cgit_free_commitinfo(struct commitinfo *info)
{
	free(info->author);
	free(info->author_email);
	free(info->committer);
	free(info->committer_email);
	free(info->subject);
	free(info->msg);
	free(info->msg_encoding);
	free(info);
	return NULL;
}

char *trim_end(const char *str, char c)
{
	int len;

	if (str == NULL)
		return NULL;
	len = strlen(str);
	while(len > 0 && str[len - 1] == c)
		len--;
	if (len == 0)
		return NULL;
	return xstrndup(str, len);
}

char *strlpart(char *txt, int maxlen)
{
	char *result;

	if (!txt)
		return txt;

	if (strlen(txt) <= maxlen)
		return txt;
	result = xmalloc(maxlen + 1);
	memcpy(result, txt, maxlen - 3);
	result[maxlen-1] = result[maxlen-2] = result[maxlen-3] = '.';
	result[maxlen] = '\0';
	return result;
}

char *strrpart(char *txt, int maxlen)
{
	char *result;

	if (!txt)
		return txt;

	if (strlen(txt) <= maxlen)
		return txt;
	result = xmalloc(maxlen + 1);
	memcpy(result + 3, txt + strlen(txt) - maxlen + 4, maxlen - 3);
	result[0] = result[1] = result[2] = '.';
	return result;
}

void cgit_add_ref(struct reflist *list, struct refinfo *ref)
{
	size_t size;

	if (list->count >= list->alloc) {
		list->alloc += (list->alloc ? list->alloc : 4);
		size = list->alloc * sizeof(struct refinfo *);
		list->refs = xrealloc(list->refs, size);
	}
	list->refs[list->count++] = ref;
}

struct refinfo *cgit_mk_refinfo(const char *refname, const unsigned char *sha1)
{
	struct refinfo *ref;

	ref = xmalloc(sizeof (struct refinfo));
	ref->refname = xstrdup(refname);
	ref->object = parse_object(sha1);
	switch (ref->object->type) {
	case OBJ_TAG:
		ref->tag = cgit_parse_tag((struct tag *)ref->object);
		break;
	case OBJ_COMMIT:
		ref->commit = cgit_parse_commit((struct commit *)ref->object);
		break;
	}
	return ref;
}

int cgit_refs_cb(const char *refname, const unsigned char *sha1, int flags,
		  void *cb_data)
{
	struct reflist *list = (struct reflist *)cb_data;
	struct refinfo *info = cgit_mk_refinfo(refname, sha1);

	if (info)
		cgit_add_ref(list, info);
	return 0;
}

void cgit_diff_tree_cb(struct diff_queue_struct *q,
		       struct diff_options *options, void *data)
{
	int i;

	for (i = 0; i < q->nr; i++) {
		if (q->queue[i]->status == 'U')
			continue;
		((filepair_fn)data)(q->queue[i]);
	}
}

static int load_mmfile(mmfile_t *file, const unsigned char *sha1)
{
	enum object_type type;

	if (is_null_sha1(sha1)) {
		file->ptr = (char *)"";
		file->size = 0;
	} else {
		file->ptr = read_sha1_file(sha1, &type, 
		                           (unsigned long *)&file->size);
	}
	return 1;
}

/*
 * Receive diff-buffers from xdiff and concatenate them as
 * needed across multiple callbacks.
 *
 * This is basically a copy of xdiff-interface.c/xdiff_outf(),
 * ripped from git and modified to use globals instead of
 * a special callback-struct.
 */
char *diffbuf = NULL;
int buflen = 0;

int filediff_cb(void *priv, mmbuffer_t *mb, int nbuf)
{
	int i;

	for (i = 0; i < nbuf; i++) {
		if (mb[i].ptr[mb[i].size-1] != '\n') {
			/* Incomplete line */
			diffbuf = xrealloc(diffbuf, buflen + mb[i].size);
			memcpy(diffbuf + buflen, mb[i].ptr, mb[i].size);
			buflen += mb[i].size;
			continue;
		}

		/* we have a complete line */
		if (!diffbuf) {
			((linediff_fn)priv)(mb[i].ptr, mb[i].size);
			continue;
		}
		diffbuf = xrealloc(diffbuf, buflen + mb[i].size);
		memcpy(diffbuf + buflen, mb[i].ptr, mb[i].size);
		((linediff_fn)priv)(diffbuf, buflen + mb[i].size);
		free(diffbuf);
		diffbuf = NULL;
		buflen = 0;
	}
	if (diffbuf) {
		((linediff_fn)priv)(diffbuf, buflen);
		free(diffbuf);
		diffbuf = NULL;
		buflen = 0;
	}
	return 0;
}

int cgit_diff_files(const unsigned char *old_sha1,
		    const unsigned char *new_sha1, unsigned long *old_size,
		    unsigned long *new_size, int *binary, int context,
		    int ignorews, linediff_fn fn)
{
	mmfile_t file1, file2;
	xpparam_t diff_params;
	xdemitconf_t emit_params;
	xdemitcb_t emit_cb;

	if (!load_mmfile(&file1, old_sha1) || !load_mmfile(&file2, new_sha1))
		return 1;

	*old_size = file1.size;
	*new_size = file2.size;

	if ((file1.ptr && buffer_is_binary(file1.ptr, file1.size)) ||
	    (file2.ptr && buffer_is_binary(file2.ptr, file2.size))) {
		*binary = 1;
		if (file1.size)
			free(file1.ptr);
		if (file2.size)
			free(file2.ptr);
		return 0;
	}

	memset(&diff_params, 0, sizeof(diff_params));
	memset(&emit_params, 0, sizeof(emit_params));
	memset(&emit_cb, 0, sizeof(emit_cb));
	diff_params.flags = XDF_NEED_MINIMAL;
	if (ignorews)
		diff_params.flags |= XDF_IGNORE_WHITESPACE;
	emit_params.ctxlen = context > 0 ? context : 3;
	emit_params.flags = XDL_EMIT_FUNCNAMES;
	emit_cb.outf = filediff_cb;
	emit_cb.priv = fn;
	xdl_diff(&file1, &file2, &diff_params, &emit_params, &emit_cb);
	if (file1.size)
		free(file1.ptr);
	if (file2.size)
		free(file2.ptr);
	return 0;
}

void cgit_diff_tree(const unsigned char *old_sha1,
		    const unsigned char *new_sha1,
		    filepair_fn fn, const char *prefix, int ignorews)
{
	struct diff_options opt;
	int prefixlen;

	diff_setup(&opt);
	opt.output_format = DIFF_FORMAT_CALLBACK;
	opt.detect_rename = 1;
	opt.rename_limit = ctx.cfg.renamelimit;
	DIFF_OPT_SET(&opt, RECURSIVE);
	if (ignorews)
		DIFF_XDL_SET(&opt, IGNORE_WHITESPACE);
	opt.format_callback = cgit_diff_tree_cb;
	opt.format_callback_data = fn;
	if (prefix) {
		opt.nr_paths = 1;
		opt.paths = &prefix;
		prefixlen = strlen(prefix);
		opt.pathlens = &prefixlen;
	}
	diff_setup_done(&opt);

	if (old_sha1 && !is_null_sha1(old_sha1))
		diff_tree_sha1(old_sha1, new_sha1, "", &opt);
	else
		diff_root_tree_sha1(new_sha1, "", &opt);
	diffcore_std(&opt);
	diff_flush(&opt);
}

void cgit_diff_commit(struct commit *commit, filepair_fn fn, const char *prefix)
{
	unsigned char *old_sha1 = NULL;

	if (commit->parents)
		old_sha1 = commit->parents->item->object.sha1;
	cgit_diff_tree(old_sha1, commit->object.sha1, fn, prefix,
		       ctx.qry.ignorews);
}

int cgit_parse_snapshots_mask(const char *str)
{
	const struct cgit_snapshot_format *f;
	static const char *delim = " \t,:/|;";
	int tl, sl, rv = 0;

	/* favor legacy setting */
	if(atoi(str))
		return 1;
	for(;;) {
		str += strspn(str,delim);
		tl = strcspn(str,delim);
		if (!tl)
			break;
		for (f = cgit_snapshot_formats; f->suffix; f++) {
			sl = strlen(f->suffix);
			if((tl == sl && !strncmp(f->suffix, str, tl)) ||
			   (tl == sl-1 && !strncmp(f->suffix+1, str, tl-1))) {
				rv |= f->bit;
				break;
			}
		}
		str += tl;
	}
	return rv;
}

typedef struct {
	char * name;
	char * value;
} cgit_env_var;

void cgit_prepare_repo_env(struct cgit_repo * repo)
{
	cgit_env_var env_vars[] = {
		{ .name = "CGIT_REPO_URL", .value = repo->url },
		{ .name = "CGIT_REPO_NAME", .value = repo->name },
		{ .name = "CGIT_REPO_PATH", .value = repo->path },
		{ .name = "CGIT_REPO_OWNER", .value = repo->owner },
		{ .name = "CGIT_REPO_DEFBRANCH", .value = repo->defbranch },
		{ .name = "CGIT_REPO_SECTION", .value = repo->section },
		{ .name = "CGIT_REPO_CLONE_URL", .value = repo->clone_url }
	};
	int env_var_count = ARRAY_SIZE(env_vars);
	cgit_env_var *p, *q;
	static char *warn = "cgit warning: failed to set env: %s=%s\n";

	p = env_vars;
	q = p + env_var_count;
	for (; p < q; p++)
		if (p->value && setenv(p->name, p->value, 1))
			fprintf(stderr, warn, p->name, p->value);
}

int cgit_open_filter(struct cgit_filter *filter)
{

	filter->old_stdout = chk_positive(dup(STDOUT_FILENO),
		"Unable to duplicate STDOUT");
	chk_zero(pipe(filter->pipe_fh), "Unable to create pipe to subprocess");
	filter->pid = chk_non_negative(fork(), "Unable to create subprocess");
	if (filter->pid == 0) {
		close(filter->pipe_fh[1]);
		chk_non_negative(dup2(filter->pipe_fh[0], STDIN_FILENO),
			"Unable to use pipe as STDIN");
		execvp(filter->cmd, filter->argv);
		die("Unable to exec subprocess %s: %s (%d)", filter->cmd,
			strerror(errno), errno);
	}
	close(filter->pipe_fh[0]);
	chk_non_negative(dup2(filter->pipe_fh[1], STDOUT_FILENO),
		"Unable to use pipe as STDOUT");
	close(filter->pipe_fh[1]);
	return 0;
}

int cgit_close_filter(struct cgit_filter *filter)
{
	chk_non_negative(dup2(filter->old_stdout, STDOUT_FILENO),
		"Unable to restore STDOUT");
	close(filter->old_stdout);
	if (filter->pid < 0)
		return 0;
	waitpid(filter->pid, &filter->exitstatus, 0);
	if (WIFEXITED(filter->exitstatus) && !WEXITSTATUS(filter->exitstatus))
		return 0;
	die("Subprocess %s exited abnormally", filter->cmd);
}

/* Read the content of the specified file into a newly allocated buffer,
 * zeroterminate the buffer and return 0 on success, errno otherwise.
 */
int readfile(const char *path, char **buf, size_t *size)
{
	int fd, e;
	struct stat st;

	fd = open(path, O_RDONLY);
	if (fd == -1)
		return errno;
	if (fstat(fd, &st)) {
		e = errno;
		close(fd);
		return e;
	}
	if (!S_ISREG(st.st_mode)) {
		close(fd);
		return EISDIR;
	}
	*buf = xmalloc(st.st_size + 1);
	*size = read_in_full(fd, *buf, st.st_size);
	e = errno;
	(*buf)[*size] = '\0';
	close(fd);
	return (*size == st.st_size ? 0 : e);
}

int is_token_char(char c)
{
	return isalnum(c) || c == '_';
}

/* Replace name with getenv(name), return pointer to zero-terminating char
 */
char *expand_macro(char *name, int maxlength)
{
	char *value;
	int len;

	len = 0;
	value = getenv(name);
	if (value) {
		len = strlen(value);
		if (len > maxlength)
			len = maxlength;
		strncpy(name, value, len);
	}
	return name + len;
}

#define EXPBUFSIZE (1024 * 8)

/* Replace all tokens prefixed by '$' in the specified text with the
 * value of the named environment variable.
 * NB: the return value is a static buffer, i.e. it must be strdup'd
 * by the caller.
 */
char *expand_macros(const char *txt)
{
	static char result[EXPBUFSIZE];
	char *p, *start;
	int len;

	p = result;
	start = NULL;
	while (p < result + EXPBUFSIZE - 1 && txt && *txt) {
		*p = *txt;
		if (start) {
			if (!is_token_char(*txt)) {
				if (p - start > 0) {
					*p = '\0';
					len = result + EXPBUFSIZE - start - 1;
					p = expand_macro(start, len) - 1;
				}
				start = NULL;
				txt--;
			}
			p++;
			txt++;
			continue;
		}
		if (*txt == '$') {
			start = p;
			txt++;
			continue;
		}
		p++;
		txt++;
	}
	*p = '\0';
	if (start && p - start > 0) {
		len = result + EXPBUFSIZE - start - 1;
		p = expand_macro(start, len);
		*p = '\0';
	}
	return result;
}