#!@PERL_BINARY@
# Copyright (C) 2000, HELM Team.
#
# This file is part of HELM, an Hypertextual, Electronic
# Library of Mathematics, developed at the Computer Science
# Department, University of Bologna, Italy.
#
# HELM is free software; you can redistribute it and/or
# modify it under the terms of the GNU General Public License
# as published by the Free Software Foundation; either version 2
# of the License, or (at your option) any later version.
#
# HELM is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
# GNU General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with HELM; if not, write to the Free Software
# Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
#
# For details, see the HELM World-Wide-Web page,
# http://cs.unibo.it/helm/.
# First of all, let's load HELM configuration
use Env;
my $HELM_LIB_DIR = $ENV{"HELM_LIB_DIR"};
# this should be the only fixed constant
my $DEFAULT_HELM_LIB_DIR = "@HELM_LIB_DIR@";
if (defined ($HELM_LIB_DIR)) {
$HELM_LIB_PATH = $HELM_LIB_DIR."/configuration.pl";
} else {
$HELM_LIB_PATH = $DEFAULT_HELM_LIB_DIR."/configuration.pl";
}
# Let's override the configuration file
$styles_dir = $ENV{"HELM_STYLE_DIR"} if (defined ($ENV{"HELM_STYLE_DIR"}));
$dtd_dir = $ENV{"HELM_DTD_DIR"} if (defined ($ENV{"HELM_DTD_DIR"}));
# : TODO temporary, move this setting to configuration file
# set the cache mode, may be "gzipped" or "normal"
my $cachemode = $ENV{'HTTP_GETTER_CACHE_MODE'} || 'gzipped';
if (($cachemode ne 'gzipped') and ($cachemode ne 'normal')) {
die "Invalid HTTP_GETTER_CACHE_MODE environment variable, must be".
"'normal' or 'gzipped'\n";
}
#
# next require defines: $helm_dir, $html_link, $dtd_dir, $uris_dbm
require $HELM_LIB_PATH;
use HTTP::Daemon;
use HTTP::Status;
use HTTP::Request;
use LWP::UserAgent;
use DB_File;
use Compress::Zlib;
#CSC: mancano i controlli sulle condizioni di errore di molte funzioni
#CSC: ==> non e' robusto
#CSC: altra roba da sistemare segnata con CSC
my $d = new HTTP::Daemon LocalPort => 8081;
my $myownurl = $d->url;
$myownurl =~ s/\/$//; # chop the final slash
tie(%map, 'DB_File', $uris_dbm.".db", O_RDONLY, 0664);
print "Please contact me at: \n";
print "helm_dir: $helm_dir\n";
print "styles_dir: $styles_dir\n";
print "dtd_dir: $dtd_dir\n";
print "urls_of_uris.db: $uris_dbm.db\n";
print "cache mode: $cachemode\n";
$SIG{CHLD} = "IGNORE"; # do not accumulate defunct processes
$SIG{USR1} = \&update; # sent by the child to make the parent update
while (my $c = $d->accept) {
if (fork() == 0) {
while (my $r = $c->get_request) {
#CSC: mancano i controlli di sicurezza
my $inputuri = $r->url;
$inputuri =~ s/^[^?]*\?uri=(.*)/$1/;
print "\nRequest: ".$r->url."\n\n";
my $http_method = $r->method;
my $http_path = $r->url->path;
if ($http_method eq 'GET' and $http_path eq "/getciconly") {
# finds the uri, url and filename
my $cicuri = $inputuri;
my $cicfilename = $cicuri;
$cicfilename =~ s/cic:(.*)/$1/;
$cicfilename =~ s/theory:(.*)/$1/;
my $cicurl = $map{$cicuri};
my $extension;
if ($cicurl =~ /\.xml$/) { # non gzipped file
$extension = ".xml";
} elsif ($cicurl =~ /\.xml\.gz$/) { # gzipped file
$extension = ".xml.gz";
} else { # error: unknown extension
die "unexpected extension in url: $cicurl, might be '.xml'".
"or '.xml.gz'";
}
$cicfilename = $helm_dir.$cicfilename.$extension;
if (!defined($cicurl)) {
print "\nNOT FOUND!!!!!\n";
$c->send_error(RC_NOT_FOUND)
} else {
print_request("cic",$cicuri,$cicurl,$cicfilename);
# Retrieves the file
my $ciccontent = download(0,"cic",$cicurl,$cicfilename);
# Answering the client
answer($c,$ciccontent);
}
} elsif ($http_method eq 'GET' and $http_path eq "/get") {
# finds the uris, urls and filenames
my $cicuri = $inputuri,
$typesuri = $inputuri,
$annuri = $inputuri;
my $annsuffix;
if ($inputuri =~ /\.types$/) {
$cicuri =~ s/(.*)\.types$/$1/;
undef($annuri);
} elsif ($inputuri =~ /\.types\.ann$/) {
$cicuri =~ s/(.*)\.types\.ann$/$1/;
$typesuri =~ s/(.*)\.ann$/$1/;
$annsuffix = ".types.ann";
} elsif ($inputuri =~ /\.ann$/) {
$cicuri =~ s/(.*)\.ann$/$1/;
undef($typesuri);
$annsuffix = ".ann";
} else {
undef($typesuri);
undef($annuri);
}
my $cicfilename = $cicuri;
$cicfilename =~ s/cic:(.*)/$1/;
$cicfilename =~ s/theory:(.*)/$1/;
$cicfilename = $helm_dir.$cicfilename;
my $cicurl = $map{$cicuri};
my $typesurl = $map{$typesuri} if (defined($typesuri));
my $annurl = $map{$annuri} if (defined($annuri));
my ($cicext, $typesext, $annext);
if ($cicurl =~ /\.xml$/) { # normal file
$cicext = ".xml";
} elsif ($cicurl =~ /\.xml\.gz$/) { # gzipped file
$cicext = ".xml.gz";
} else {
die "unexpected extension in url: $cicurl;".
"might be '.xml' or '.xml.gz'";
}
if (defined($typesuri)) { # extension selection for types file
if ($typesurl =~ /\.xml$/) { # normal file
$typesext = ".types.xml";
} elsif ($typesurl =~ /\.xml\.gz$/) { # gzipped file
$typesext = ".types.xml.gz";
} else {
die "unexpected extension in url: $typesurl;".
"might be '.xml' or '.xml.gz'";
}
}
if (defined($annuri)) { # extension selection for annotation file
if ($annurl =~ /\.xml$/) { # normal file
$annext = ".xml";
} elsif ($annurl =~ /\.xml\.gz$/) { # gzipped file
$annext = ".xml.gz";
} else {
die "unexpected extension in url: $annurl".
"might be '.xml' or '.xml.gz'";
}
}
my $typesfilename = $cicfilename.$typesext if $typesuri;
my $annfilename = $cicfilename.$annsuffix.$annext if $annuri;
$cicfilename .= $cicext;
if (!defined($cicurl) ||
(!defined($typesurl) && $typesuri) ||
(!defined($annuri) && $annuri))
{
print "\nNOT FOUND!!!!!\n";
$c->send_error(RC_NOT_FOUND)
} else {
print_request("cic",$cicuri,$cicurl,$cicfilename);
print_request("types",$typesuri,$typesurl,$typesfilename)
if ($typesuri);
print_request("ann",$annuri,$annurl,$annfilename)
if ($annuri);
# Retrieves the files
my $ciccontent = download(1,"cic",$cicurl,$cicfilename);
my $typescontent =
download(1,"types",$typesurl,$typesfilename) if ($typesuri);
my $anncontent =
download(1,"ann",$annurl,$annfilename) if ($annuri);
# Merging the files together
my $merged = <
$ciccontent
$typescontent
$anncontent
EOT
# Answering the client
answer($c,$merged);
}
} elsif ($http_method eq 'GET' and $http_path eq "/getdtd") {
my $filename = $inputuri;
$filename = $dtd_dir."/".$filename;
print "DTD: $inputuri ==> ($filename)\n";
if (stat($filename)) {
print "Using local copy\n";
open(FD, $filename) or die "Cannot open $filename\n";
$cont = "";
while() { $cont .= $_; }
close(FD);
answer($c,$cont);
} else {
die "Could not find DTD!";
}
} elsif ($http_method eq 'GET' and $http_path eq "/getxslt") {
my $filename = $inputuri;
$filename = $styles_dir."/".$filename;
print "XSLT: $inputuri ==> ($filename)\n";
if (stat($filename)) {
print "Using local copy\n";
open(FD, $filename) or die "Cannot open $filename\n";
$cont = "";
while() {
# Vary bad heuristic for substituion of absolute URLs
# for relative ones
s/xsl:import\s+href="/xsl:import href="$myownurl\/getxslt?uri=/g ;
s/xsl:include\s+href="/xsl:include href="$myownurl\/getxslt?uri=/g ;
$cont .= $_;
}
close(FD);
answer($c,$cont);
} else {
die "Could not find XSLT!";
}
} elsif ($http_method eq 'GET' and $http_path eq "/conf") {
my $quoted_html_link = $html_link;
$quoted_html_link =~ s/&/&/g;
$quoted_html_link =~ s/</g;
$quoted_html_link =~ s/>/>/g;
$quoted_html_link =~ s/'/'/g;
$quoted_html_link =~ s/"/"/g;
print "\nConfiguration requested, returned #$quoted_html_link#\n";
$cont = "$quoted_html_link";
answer($c,$cont);
} elsif ($http_method eq 'GET' and $http_path eq "/update") {
print "Update requested...";
update();
kill(USR1,getppid());
print " done\n";
answer($c,"Update done
");
} else {
print "\nINVALID REQUEST!!!!!\n";
$c->send_error(RC_FORBIDDEN)
}
print "\nRequest solved: ".$r->url."\n\n";
}
$c->close;
undef($c);
print "\nCONNECTION CLOSED\n\n";
exit;
} # fork
}
#================================
#CSC: Too much powerful: creates even /home, /home/users/, ...
#CSC: Does not raise errors if could not create dirs/files
sub mkdirs
{
my ($pathname) = @_;
my @dirs = split /\//,$pathname;
my $tmp;
foreach $dir (@dirs) {
$tmp = ((defined($tmp)) ? $tmp."\/".$dir : "");
mkdir($tmp,0777);
}
rmdir($tmp);
}
sub print_request
{
my ($str,$uri,$url,$filename) = @_;
print $str."uri: $uri\n";
print $str."url: $url\n";
print $str."filename: $filename\n\n";
}
sub callback
{
my ($data) = @_;
$cont .= $data;
}
sub gunzip { # gunzip a file and return the deflated content
my ($filename) = @_;
my ($gz, $buffer, $cont);
print "deflating $filename ...\n";
$gz = gzopen($filename, "r")
or die "Cannot open gzip'ed file $filename: $gzerrno";
$cont = "";
while ( $gz->gzread($buffer) > 0 ) {
$cont .= $buffer;
}
die "Error while reading : $gzerrno\n" if $gzerrno != Z_STREAM_END ;
$gz->gzclose();
return $cont;
}
sub gzip { # gzip the content argument and save it to filename argument
my ($cont, $filename) = @_;
my ($gz, $cont);
$gz = gzopen($filename, "w")
or die "Cannot gzopen for writing file $filename: $gzerrno";
$gz->gzwrite($cont) or die "error writing: $gzerrno\n" ;
$gz->gzclose();
}
sub download
{
my ($remove_headers,$str,$url,$filename) = @_;
my ($gz, $buffer);
my $resourcetype; # retrieve mode: "normal" (.xml) or "gzipped" (.xml.gz)
if ($filename =~ /\.xml$/) { # set retrieve mode
$resourcetype = "normal";
} elsif ($filename =~ /\.xml\.gz$/) {
$resourcetype = "gzipped";
} else {
die "Unsupported download extension, might be '.gz' or '.xml'\n";
}
my $basefname = $filename;
$basefname =~ s/\.gz$//; # get base resource name removing trailing .gz
$cont = ""; # modified by side-effect by the callback function
my $localfname="";
if (stat($basefname)) {
$localfname=$basefname;
} elsif (stat($basefname.".gz")) {
$localfname=$basefname.".gz";
}
if ($localfname ne "") { # we already have local copy of requested file
# check both possible cache entry: gzipped or normal
print "Using local copy for the $str file\n";
if ($localfname =~ /\.xml\.gz$/) { # deflating cached file and return it
$cont = gunzip($localfname);
} elsif ($localfname =~ /\.xml$/) { # just return cached file
open(FD, $localfname) or die "Cannot open $localfname";
while() { $cont .= $_; }
close(FD);
} else { # error
die "Internal error: unexpected file name $localfname,"
."must end with '.gz' or '.xml.gz'\n";
}
} else { # download file from net
print "Downloading the $str file\n"; # download file
$ua = LWP::UserAgent->new;
$request = HTTP::Request->new(GET => "$url");
$response = $ua->request($request, \&callback);
# cache retrieved file to disk
# TODO: inefficent, I haven't yet undestood how to deflate
# in memory gzipped file, without call "gzopen"
print "Storing the $str file\n";
mkdirs($filename);
open(FD, ">".$filename.".tmp") or die "Cannot open $filename.tmp\n";
print FD $cont;
close(FD);
# handle cache conversion normal->gzipped or gzipped->normal as user choice
if (($cachemode eq 'normal') and ($resourcetype eq 'normal')) {
# cache the file as is
rename "$filename.tmp", $filename;
} elsif (($cachemode eq 'gzipped') and ($resourcetype eq 'gzipped')) {
# cache the file as is
# and update the $cont variabile with deflated content
rename "$filename.tmp", $filename;
$cont = gunzip($filename);
} elsif (($cachemode eq 'normal') and ($resourcetype eq 'gzipped')) {
# deflate cache entry
# and update $cont
open(FD, "> $basefname") or die "cannot open $basefname\n";
$cont = gunzip($filename.".tmp");
print FD $cont;
close(FD);
unlink "$filename.tmp"; # delete old gzipped file
} elsif (($cachemode eq 'gzipped') and ($resourcetype eq 'normal')) {
# compress cache entry
gzip($cont, $basefname.".gz");
unlink "$filename.tmp"; # delete old uncompressed file
} else {
die "Internal error, unsopported cachemode, resourcetype couple\n";
}
# $cont now contained uncompressed data
}
if ($remove_headers) {
$cont =~ s/<\?xml [^?]*\?>//sg;
$cont =~ s/]*>//sg;
}
return $cont;
}
sub answer
{
my ($c,$cont) = @_;
my $res = new HTTP::Response;
$res->content($cont);
$c->send_response($res);
}
sub update {
untie %map;
tie(%map, 'DB_File', $uris_dbm.".db", O_RDONLY, 0664);
}