#!/usr/bin/perl -s
#
# cvsweb - a CGI interface to the CVS tree.
#
# Written by Bill Fenner <fenner@parc.xerox.com> on his own time.
# Insert BSD copyright here.
#
#HTTP_USER_AGENT: Mozilla/1.1N (X11; I; SunOS 4.1.3_U1 sun4m) via proxy gateway CERN-HTTPD/3.0 libwww/2.17
#SERVER_NAME: www.freebsd.org
#QUERY_STRING: baz
#SCRIPT_FILENAME: /usr/local/www/cgi-bin/env.pl
#SERVER_PORT: 80
#HTTP_ACCEPT: */*, image/gif, image/x-xbitmap, image/jpeg
#SERVER_PROTOCOL: HTTP/1.0
#HTTP_COOKIE: s=beta26429821397802167
#PATH_INFO: /foo/bar
#REMOTE_ADDR: 13.1.64.94
#DOCUMENT_ROOT: /usr/local/www/data/
#PATH: /sbin:/bin:/usr/sbin:/usr/bin
#PATH_TRANSLATED: /usr/local/www/data//foo/bar
#GATEWAY_INTERFACE: CGI/1.1
#REQUEST_METHOD: GET
#SCRIPT_NAME: /cgi-bin/env.pl
#SERVER_SOFTWARE: Apache/1.0.0
#REMOTE_HOST: beta.xerox.com
#SERVER_ADMIN: webmaster@freebsd.org
#
require 'timelocal.pl';
require 'ctime.pl';

$hsty_base = "";
require 'cgi-style.pl';

$cvsroot = '/home/ncvs';
$intro = "
This is a WWW interface to the FreeBSD CVS tree.
You can browse the file hierarchy by picking directories
(which have slashes after them, e.g. <b>src/</b>).
If you pick a file, you will see the revision history
for that file.
Selecting a revision number will download that revision of
the file.  There is a link at each revision to display
diffs between that revision and the previous one, and
a form at the bottom of the page that allows you to
display diffs between arbitrary revisions.
<p>
Please send any suggestions, comments, etc. to
<A HREF=\"mailto:fenner@freebsd.org\">Bill Fenner &lt;fenner@freebsd.org&gt;</A>
";
$shortinstr = "
Click on a directory to enter that directory. Click on a file to display
its revision history and to get a
chance to display diffs between revisions. 
";

$verbose = $v;
($where = $ENV{'PATH_INFO'}) =~ s|^/||;
$where =~ s|/$||;
$fullname = $cvsroot . '/' . $where;
($scriptname = $ENV{'SCRIPT_NAME'}) =~ s|^/?|/|;
$scriptname =~ s|/$||;
$scriptwhere = $scriptname . '/' . $where;
$scriptwhere =~ s|/$||;

if (!-d $cvsroot) {
	&fatal("500 Internal Error",'$CVSROOT not found!');
}
if (-d $fullname) {
# Something that would be nice to support, although I have no real
# good idea of how, would be to get full directory diff's, using
# symbolic names (revision numbers would be meaningless).
# The problem is finding a list of symbolic names that is common
# to all the files in the directory.
#
	opendir(DIR, $fullname) || &fatal("404 Not Found","$where: $!");
	@dir = readdir(DIR);
	closedir(DIR);
	if ($where eq '') {
	    print &html_header("FreeBSD CVS Repository");
	    print $intro;
	} else {
	    print &html_header("/$where");
	    print $shortinstr;
	}
	print "<p>Current directory: <b>/$where</b>\n";
	print "<P><HR NOSHADE>\n";
	# Using <MENU> in this manner violates the HTML2.0 spec but
	# provides the results that I want in most browsers.  Another
	# case of layout spooging up HTML.
	print "<MENU>\n";
	foreach (sort @dir) {
	    if ($_ eq '.') {
		next;
	    }
	    if ($_ eq '..') {
		next if ($where eq '');
		($updir = $scriptwhere) =~ s|[^/]+$||;
		print "<IMG SRC=\"/icons/back.gif\"> ",
		    &link("Previous Directory",$updir), "<BR>";
	    } elsif (-d $fullname . "/" . $_) {
		print "<IMG SRC=\"/icons/dir.gif\"> ",
		    &link($_ . "/", $scriptwhere . '/' . $_ . '/'), "<BR>";
	    } elsif (s/,v$//) {
		print "<IMG SRC=\"/icons/text.gif\"> ",
		    &link($_, $scriptwhere . '/' . $_), "<BR>";
	    }
	}
	print "</MENU>\n";
	print &html_footer;
	print "</BODY></HTML>\n";
} elsif (-f $fullname . ',v') {
	if ($_ = $ENV{'QUERY_STRING'}) {
	    s/%(..)/sprintf("%c", hex($1))/ge;	# unquote %-quoted
	    if (/rev=([\d\.]+)/) {
		$rev = $1;
		open(RCS, "co -p$rev '$fullname' 2>&1 |") ||
		    &fail("500 Internal Error", "Couldn't co: $!");
# /home/ncvs/src/sys/netinet/igmp.c,v  -->  standard output
# revision 1.1.1.2
# /*
		$_ = <RCS>;
		if (/^$fullname,v\s+-->\s+standard output\s*$/o) {
		    # As expected
		} else {
		    &fatal("500 Internal Error",
			"Unexpected output from co: $_");
		}
		$_ = <RCS>;
		if (/^revision\s+$rev\s*$/) {
		    # As expected
		} else {
		    &fatal("500 Internal Error",
			"Unexpected output from co: $_");
		}
		$| = 1;
		print "Content-type: text/plain\n";
		print "Content-encoding: x-gzip\n\n";
		open(GZIP, "|gzip -1 -c");	# need lightweight compression
		print GZIP <RCS>;
		close(GZIP);
		close(RCS);
		exit;
	    }
	    if (/r1=([^&:]+)(:([^&]+))?/) {
		$rev1 = $1;
		$sym1 = $3;
	    }
	    if ($rev1 eq 'text') {
		if (/tr1=([^&]+)/) {
		    $rev1 = $1;
		}
	    }
	    if (/r2=([^&:]+)(:([^&]+))?/) {
		$rev2 = $1;
		$sym2 = $3;
	    }
	    if ($rev2 eq 'text') {
		if (/tr2=([^&]+)/) {
		    $rev2 = $1;
		}
	    }
	    if (!($rev1 =~ /^[\d\.]+$/) || !($rev2 =~ /^[\d\.]+$/)) {
		&fatal("404 Not Found",
			"Malformed query \"$ENV{'QUERY_STRING'}\"");
	    }
#
# rev1 and rev2 are now both numeric revisions.
# Thus we do a DWIM here and swap them if rev1 is after rev2.
# XXX should we warn about the fact that we do this?
	    if (&revcmp($rev1,$rev2) > 0) {
		($tmp1, $tmp2) = ($rev1, $sym1);
		($rev1, $sym1) = ($rev2, $sym2);
		($rev2, $sym2) = ($tmp1, $tmp2);
	    }
#
	    $difftype = "-u";
	    $diffname = "Unidiff";
	    if (/f=([^&]+)/) {
		if ($1 eq 'c') {
		    $difftype = '-c';
		    $diffname = "Context diff";
		}
	    }
# XXX should this just be text/plain
# or should it have an HTML header and then a <pre>
	    print "Content-type: text/plain\n\n";
	    open(RCSDIFF, "rcsdiff $difftype -r$rev1 -r$rev2 '$fullname' 2>&1 |") ||
		&fail("500 Internal Error", "Couldn't rcsdiff: $!");
#
#===================================================================
#RCS file: /home/ncvs/src/sys/netinet/tcp_output.c,v
#retrieving revision 1.16
#retrieving revision 1.17
#diff -c -r1.16 -r1.17
#*** /home/ncvs/src/sys/netinet/tcp_output.c     1995/11/03 22:08:08     1.16
#--- /home/ncvs/src/sys/netinet/tcp_output.c     1995/12/05 17:46:35     1.17
#
# Ideas:
# - nuke the stderr output if it's what we expect it to be
# - Add "no differences found" if the diff command supplied no output.
#
#*** src/sys/netinet/tcp_output.c     1995/11/03 22:08:08     1.16
#--- src/sys/netinet/tcp_output.c     1995/12/05 17:46:35     1.17 RELENG_2_1_0
# (bogus example, but...)
#
	    if ($difftype eq '-u') {
		$f1 = '---';
		$f2 = '\+\+\+';
	    } else {
		$f1 = '\*\*\*';
		$f2 = '---';
	    }
	    while (<RCSDIFF>) {
		if (m|^$f1 $cvsroot|o) {
		    s|$cvsroot/||o;
		    if ($sym1) {
			chop;
			$_ .= " " . $sym1 . "\n";
		    }
		} elsif (m|^$f2 $cvsroot|o) {
		    s|$cvsroot/||o;
		    if ($sym2) {
			chop;
			$_ .= " " . $sym2 . "\n";
		    }
		}
		print $_;
	    }
	    close(RCSDIFF);
	    exit;
	}
	open(RCS, "rlog '$fullname'|") || &fatal("500 Internal Error",
						"Failed to spawn rlog");
	while (<RCS>) {
	    print if ($verbose);
	    if ($symnames) {
		if (/^\s+([^:]+):\s+([\d\.]+)/) {
		    $symrev{$1} = $2;
		    if ($revsym{$2}) {
			$revsym{$2} .= ", ";
		    }
		    $revsym{$2} .= $1;
		} else {
		    $symnames = 0;
		}
	    } elsif (/^symbolic names/) {
		$symnames = 1;
	    } elsif (/^-----/) {
		last;
	    }
	}
# each log entry is of the form:
# ----------------------------
# revision 3.7.1.1
# date: 1995/11/29 22:15:52;  author: fenner;  state: Exp;  lines: +5 -3
# log info
# ----------------------------
	logentry:
	while (!/^=========/) {
	    $_ = <RCS>;
	    print "R:", $_ if ($verbose);
	    if (/^revision ([\d\.]+)/) {
		$rev = $1;
	    } elsif (/^========/ || /^----------------------------$/) {
		next logentry;
	    } else {
		&fatal("500 Internal Error","Error parsing RCS output: $_");
	    }
	    $_ = <RCS>;
	    print "D:", $_ if ($verbose);
	    if (m|^date:\s+(\d+)/(\d+)/(\d+)\s+(\d+):(\d+):(\d+);\s+author:\s+(\S+);|) {
		$yr = $1;
		# damn 2-digit year routines
		if ($yr > 100) {
		    $yr -= 1900;
		}
		$date{$rev} = &timelocal($6,$5,$4,$3,$2 - 1,$yr);
		$author{$rev} = $7;
	    } else {
		&fatal("500 Internal Error", "Error parsing RCS output: $_");
	    }
	    line:
	    while (<RCS>) {
		print "L:", $_ if ($verbose);
		next line if (/^branches:\s/);
		last line if (/^----------------------------$/ || /^=========/);
		$log{$rev} .= $_;
	    }
	    print "E:", $_ if ($verbose);
	}
	close(RCS);
	print "Done reading RCS file\n" if ($verbose);
#
# Sort the revisions into commit-date order.
	@revorder = sort {$date{$b} <=> $date{$a}} keys %date;
	print "Done sorting revisions\n" if ($verbose);
#
# HEAD is an artificial tag which is simply the highest tag number on the main
# branch (I think!).  Find it by looking through @revorder; it should at least
# be near the beginning (In fact, it *should* be the first commit listed on
# the main branch.)
	revision:
	for ($i = 0; $i <= $#revorder; $i++) {
	    if ($revorder[$i] =~ /^\d+\.\d+$/) {
		if ($revsym{$revorder[$i]}) {
		    $revsym{$revorder[$i]} .= ", ";
		}
		$revsym{$revorder[$i]} .= "HEAD";
		$symrev{"HEAD"} = $revorder[$i];
		last revision;
	    }
	}
	print "Done finding HEAD\n" if ($verbose);
#
# Now that we know all of the revision numbers, we can associate
# absolute revision numbers with all of the symbolic names, and
# pass them to the form so that the same association doesn't have
# to be built then.
#
# should make this a case-insensitive sort
	foreach (sort keys %symrev) {
	    $rev = $symrev{$_};
	    if ($rev =~ /^(\d+(\.\d+)+)\.0\.(\d+)$/) {
		#
		# A revision number of A.B.0.D really translates into
		# "the highest current revision on branch A.B.D".
		#
		# If there is no branch A.B.D, then it translates into
		# the head A.B .
		#
		# This is pure speculation.
		#
		$head = $1;
		$branch = $3;
		$regex = $head . "." . $branch;
		$regex =~ s/\./\./g;
		#             <
		#           \____/
		$rev = $head;

		revision:
		foreach $r (@revorder) {
		    if ($r =~ /^${regex}/) {
			$rev = $head . "." . $branch;
			last revision;
		    }
		}
		$revsym{$rev} .= ", " if ($revsym{$rev});
		$revsym{$rev} .= $_;
	    }
	    $sel .= "<OPTION VALUE=\"${rev}:${_}\">$_\n";
	}
	print "Done associating revisions with branches\n" if ($verbose);
        print &html_header("CVS log for $where");
	($upwhere = $where) =~ s|[^/]+$||;
	print "Up to ", &link($upwhere,$scriptname . "/" . $upwhere);
	print "<BR>\n";
	print "<A HREF=\"#diff\">Request diff between arbitrary revisions</A>\n";
	print "<HR NOSHADE>\n";
# The other possible U.I. I can see is to have each revision be hot
# and have the first one you click do ?r1=foo
# and since there's no r2 it keeps going & the next one you click
# adds ?r2=foo and performs the query.
# I suppose there's no reason we can't try both and see which one
# people prefer...

	for ($i = 0; $i <= $#revorder; $i++) {
	    $_ = $revorder[$i];
            print "<a NAME=\"rev$_\"></a>\n";
#	    print "RCS revision <b>$_</b>\n";
	    print "<A HREF=\"$scriptwhere?rev=$_\"><b>$_</b></A>";
	    if (/^1\.1\.1\.\d+$/) {
		print " <i>(vendor branch)</i>";
	    }
#	    print "<BR>\n";
#	    print "Checked in on <i>" . &ctime($date{$_}) . "</i> by ";
#	    print "<i>" . $author{$_} . "</i><BR>\n";
	    print " <i>" . &ctime($date{$_}) . "</i> by ";
	    print "<i>" . $author{$_} . "</i>\n";
	    if ($revsym{$_}) {
#		print "CVS Tags: <b>$revsym{$_}</b><BR>\n";
		print "<BR>CVS Tags: <b>$revsym{$_}</b>";
	    }
	    if (($br = $_) =~ s/\.\d+$// && $revsym{$br})  {
#		print "Branch: <b>$revsym{$br}</b><BR>\n";
		if ($revsym{$_}) {
		    print "; ";
		} else {
		    print "<BR>";
		}
		print "Branch: <b>$revsym{$br}</b>";
	    }
	    # Find the previous revision on this branch.
	    # I think this can be done algorithmically.
	    @prevrev = split(/\./, $_);
	    if (--$prevrev[$#prevrev] == 0) {
		# If it was X.Y.Z.1, just make it X.Y
		if ($#prevrev > 1) {
		    pop(@prevrev);
		    pop(@prevrev);
		} else {
		    # It was rev 1.1 (XXX does CVS use revisions
		    # greater than 1.x?)
		    if ($prevrev[0] != 1) {
			print "<i>* I can't figure out the previous revision! *</i>\n";
		    }
		}
	    }
	    if ($prevrev[$#prevrev] != 0) {
		$prev = join(".", @prevrev);
		print "<BR><A HREF=\"$scriptwhere?r1=$prev";
		print "&r2=$_\">Diffs to $prev</A>\n";
		#
		# Plus, if it's on a branch, and it's not a vendor branch,
		# offer to diff with the immediately-preceding commit if it
		# is not the previous revision as calculated above
		# and if it is on the HEAD (or at least on a higher branch)
		# (e.g. change gets committed and then brought
		# over to -stable)
		if (!/^1\.1\.1\.\d+$/ && ($i != $#revorder) &&
					($prev ne $revorder[$i+1])) {
		    @tmp1 = split(/\./, $revorder[$i+1]);
		    @tmp2 = split(/\./, $_);
		    if ($#tmp1 < $#tmp2) {
			print "; <A HREF=\"$scriptwhere?r1=$revorder[$i+1]";
			print "&r2=$_\">Diffs to $revorder[$i+1]</A>\n";
		    }
		}
	    }
#	    print "Log message:<BR>\n";
	    print "<PRE>\n";
	    print &htmlify($log{$_});
	    print "</PRE><HR NOSHADE>\n";
	}
	print "<A NAME=diff>\n";
	print "This form allows you to request diff's between any two\n";
	print "revisions of a file.  You may select a symbolic revision\n";
	print "name using the selection box or you may type in a numeric\n";
	print "name using the type-in text box.\n";
	print "</A><P>\n";
	print "<FORM METHOD=\"GET\" ACTION=\"$scriptwhere\">\n";
	print "Diffs between \n";
	print "<SELECT NAME=\"r1\">\n";
	print "<OPTION VALUE=\"text\" SELECTED>Use Text Field\n";
	print $sel;
	print "</SELECT>\n";
	print "<INPUT TYPE=\"TEXT\" NAME=\"tr1\" VALUE=\"$revorder[$#revorder]\">\n";
	print " and \n";
	print "<SELECT NAME=\"r2\">\n";
	print "<OPTION VALUE=\"text\" SELECTED>Use Text Field\n";
	print $sel;
	print "</SELECT>\n";
	print "<INPUT TYPE=\"TEXT\" NAME=\"tr2\" VALUE=\"$revorder[0]\">\n";
	print "<BR><INPUT TYPE=RADIO NAME=\"f\" VALUE=u CHECKED>Unidiff<br>\n";
	print "<INPUT TYPE=RADIO NAME=\"f\" VALUE=c>Context diff<br>\n";
	print "<INPUT TYPE=SUBMIT VALUE=\"Get Diffs\">\n";
	print "</FORM>\n";
        print &html_footer;
	print "</BODY></HTML>\n";
} else {
	&fatal("404 Not Found","$where: no such file or directory");
}

sub htmlify {
	local($string) = @_;

	$string =~ s/&/&amp;/g;
	$string =~ s/</&lt;/g;
	$string =~ s/>/&gt;/g;

	$string;
}

sub link {
	local($name, $where) = @_;

	"<A HREF=\"$where\">$name</A>\n";
}

sub revcmp {
	local($rev1, $rev2) = @_;
	local(@r1) = split(/\./, $rev1);
	local(@r2) = split(/\./, $rev2);
	local($a,$b);

	while (($a = pop(@r1)) && ($b = pop(@r2))) {
	    if ($a != $b) {
		return $a <=> $b;
	    }
	}
	if (@r1) { return 1; }
	if (@r2) { return -1; }
	return 0;
}

sub fatal {
	local($errcode, $errmsg) = @_;
	print "Status: $errcode\n";
	print "Content-type: text/html\n";
	print "\n";
	print "<HTML><HEAD><TITLE>Error</TITLE></HEAD>\n";
	print "<BODY>Error: $errmsg</BODY></HTML>\n";
	exit(1);
}