cgiframe.java

很棒的web服务器源代码

    /**
     * Get the CGI debug flag.
     * @return The boolean value of the CGI debug flag.
     */

    public boolean checkCgiDebug() {
	return getBoolean(ATTR_CGI_DEBUG, false);
    }

    /**
     * Turn the given header name into it's env var canonical name.
     * This guy is crazy enough to run CGI scripts, he can pay for that 
     * overhead.
     * @param name The header name.
     * @return A String giving the official env variable name for that header.
     */

    public String getEnvName(String name) {
	int          sl = name.length();
	StringBuffer sb = new StringBuffer(5+sl);
	sb.append("HTTP_");
	for (int i = 0 ; i < sl ; i++) {
	    char ch = name.charAt(i);
	    sb.append((ch == '-') ? '_' : Character.toUpperCase(ch));
	}
	return sb.toString();
    }

    /**
     * Get this resource Etag
     * @return an instance of HttpEntityTag, or <strong>null</strong> if not
     *    defined.
     */
    public HttpEntityTag getETag() {
	if (etag == null) {
	    HttpEntityTag netag = super.getETag();
	    if (netag != null) {
		etag.setWeak(true);
	    }
	}
	return etag;
    }

    /**
     * Handle the CGI script output.
     * This methods handles the CGI script output. Depending on the
     * value of the <strong>noheader</strong> attribute it either:
     * <ul>
     * <li>Sends back the script output directly,</li>
     * <li>Parses the script output, looking for a status header or a 
     * location header, or a content-length header, or any combination
     * of those three.
     * </ul>
     * @param process The underlying CGI process.
     * @param request The processed request.
     * @exception ProtocolException If an HTTP error 
     * should be sent back to the client.
     */

    protected Reply handleCGIOutput (Process process, Request request) 
	throws ProtocolException
    {
	// first, take care of error stream
	(new ProcessErrorReader(process)).start();
	// No header script don't deserve attention:
	if ( checkNoheaderFlag() ) {
	    Reply reply = request.makeReply(HTTP.NOHEADER) ;
	    reply.setStream (process.getInputStream()) ;
	    return reply ;
	}
	// Check for debugging mode:
	if ( checkCgiDebug() ) {
	    Reply reply = request.makeReply(HTTP.OK);
	    reply.setContentType(MimeType.TEXT_PLAIN);
	    reply.setStream(process.getInputStream());
	    return reply;
	}
	// We MUST parse at least one header:
	MimeParser p = new MimeParser(process.getInputStream(),
				      new CGIHeaderHolderFactory());
	Reply           reply  = null ;
	try {
	    CGIHeaderHolder h = (CGIHeaderHolder) p.parse();
	    // Check for a status code:
	    String svalue   = h.getStatus();
	    String location = h.getLocation();
	    if ( svalue != null ) {
		int status = -1;
		try {
                    String _st = svalue.trim();
		    int _space = _st.indexOf(' ');
                    if (_space != -1) {
			_st = _st.substring(0, _space);
		    }
		    status = Integer.parseInt(_st);
		} catch (Exception ex) {
		    // This script has emited an invalid status line:
		    String msg = ("Emited an invalid status line ["+
				  svalue + "].");
		    getServer().errlog(this, msg);
		    // Throw an HTTPException:
		    reply = request.makeReply(HTTP.INTERNAL_SERVER_ERROR);
		    reply.setContent("CGI script emited invalid status.");
		    throw new HTTPException(reply);
		}
		// we will use the default for this frame, but remove
		// the length calculated from the script size.
		reply = createDefaultReply(request, status);
		reply.setContentLength(-1);
	    } else {
		// No status code available, any location header ?
		if (location != null) {
		    reply = request.makeReply(HTTP.FOUND);
		} else {
		    reply = createDefaultReply(request, HTTP.OK);
		    reply.setContentLength(-1);
		}
	    }
	    // Set up the location header if needed:
	    if ( location != null ) {
		try {
		    reply.setLocation(new URL(getURL(request), location));
		} catch (MalformedURLException ex) {
		    // This should really not happen:
		    getServer().errlog(this, "unable to create location url "+
				       location+
				       " in base "+getURL(request));
		}
	    }
	    // And then, the remaining headers:
	    Enumeration e = h.enumerateHeaders();
	    if ( e != null ) {
		while ( e.hasMoreElements() ) {
		    String hname = (String) e.nextElement();
		    reply.setValue(hname, (String) h.getValue(hname));
		}
	    }
	    reply.setStream(p.getInputStream()) ;
	} catch (IOException ex) {
	    ex.printStackTrace();
	} catch (MimeParserException ex) {
	    // This script has generated invalid output:
	    String msg = (getURL(request)
			  +": emited invalid output ["+
			  ex.getMessage() +"]");
	    getServer().errlog(this, msg);
	    // Throw an HTTPException:
	    Reply error = request.makeReply(HTTP.INTERNAL_SERVER_ERROR) ;
	    error.setContent("CGI error: unable to parse script headers.") ;
	    throw new HTTPException (error) ;
	}
	if (reply != null) {
	    reply.setDynamic(true);
	}
	return reply ;
    }

    /**
     * Add an enviornment binding to the given vector.
     * @param name The name of the enviornment variable.
     * @param val Its value.
     * @param into The vector to which accumulate bindings.
     */

    private void addEnv (String name, String val, Vector into) {
	into.addElement (name+"="+val) ;
    }

    /**
     * Prepare the command to run for this CGI script, and run it.
     * @param request The request to handle.
     * @return The running CGI process object.
     * @exception ProtocolException If we weren't able 
     * to build the command or the environment.
     * @exception IOException if an IO erro occurs.
     */

    protected Process makeCgiCommand (Request request) 
	throws ProtocolException, IOException 
    {
	// Check the command attribute first:
	String      query     = null;
	String      command[] = getCommand() ;
	if ( command == null ) {
	    Reply error = request.makeReply(HTTP.INTERNAL_SERVER_ERROR) ;
	    error.setContent("CgiResource mis-configured: it doesn't have a "
			     + " command attribute");
	    throw new HTTPException(error);
	}
	// Ok:
	Vector      env       = new Vector(32) ;
	httpd       server    = request.getClient().getServer() ;
	InetAddress sadr      = server.getInetAddress() ;
	// Specified environment variables:
	// We do not handle the following variables:
	// - REMOTE_IDENT: would require usage of IDENT protocol.
	// Authentification type, if any:
	String svalue = (String) request.getState(AuthFilter.STATE_AUTHTYPE);
	if ( svalue != null )
	    addEnv("AUTH_TYPE", svalue, env);
	// Content length, if available:
	svalue = request.getValue("content-length");
	if ( svalue != null )
	    addEnv("CONTENT_LENGTH", svalue, env);
	// Content type, if available:
	svalue = request.getValue("content-type");
	if ( svalue != null )
	    addEnv("CONTENT_TYPE", svalue, env);
	// The gateway interface, hopefully 1.1 !
	addEnv ("GATEWAY_INTERFACE", "CGI/1.1", env) ;
	// The PATH_INFO, which I am afraid I still don't understand:
	svalue = (String) request.getState(STATE_EXTRA_PATH);
	if ( svalue == null )
	    addEnv ("PATH_INFO", "/", env) ; 
	else
	    addEnv ("PATH_INFO", svalue, env) ; 
	// The query string:
	query = request.getQueryString();
	if ( query != null ) 
	    addEnv("QUERY_STRING", query, env) ;
	// The remote client IP address:
	svalue = request.getClient().getInetAddress().toString();
	addEnv ("REMOTE_ADDR", svalue, env);
	// Authentified user:
	svalue = (String) request.getState(AuthFilter.STATE_AUTHUSER);
	if ( svalue != null )
	    addEnv("REMOTE_USER", svalue, env);
	// Remote host name, if allowed:
	if ( checkRemoteHost() ) {
	    String host = request.getClient().getInetAddress().getHostName();
	    addEnv("REMOTE_HOST", host, env);
	}
	// The request method:
	addEnv ("REQUEST_METHOD", request.getMethod(), env) ;
	// The script name :
	addEnv("SCRIPT_NAME", getURLPath(), env);
	// Server name:
	addEnv ("SERVER_NAME", getServer().getHost(), env) ;
	// Server port:
	svalue = Integer.toString(getServer().getLocalPort());
	addEnv ("SERVER_PORT", svalue, env);
	// Server protocol:
	addEnv ("SERVER_PROTOCOL", request.getVersion(), env) ;
	// Server software:
	addEnv ("SERVER_SOFTWARE", server.getSoftware(), env) ;
	if (getFileResource()!= null) {
	    addEnv("PATH_TRANSLATED", 
		   getFileResource().getFile().getAbsolutePath(), env);
	}

	//Add user env
	ArrayDictionary uenv = getUserEnv();
	if (uenv != null) {
	    Enumeration names = uenv.keys();
	    while (names.hasMoreElements()) {
		String var = (String)names.nextElement();
		addEnv(var, (String)uenv.get(var), env);
	    }
	}
	// All other request fields, yeah, let's lose even more time:
	Enumeration e = request.enumerateHeaderDescriptions(false);
	while ( e.hasMoreElements() ) {
	    HeaderDescription d = (HeaderDescription) e.nextElement();
	    addEnv(getEnvName(d.getName())
		   , request.getHeaderValue(d).toString()
		   , env);
	}
	// Command line:
	if ( query != null ) {
	    String querycmd[] = new String[command.length+1] ;
	    System.arraycopy(command, 0, querycmd, 0, command.length) ;
	    querycmd[command.length] = query ;
	    command = querycmd ;
	}
	String aenv[] = new String[env.size()] ;
	env.copyInto (aenv) ;
	// Run the process:
	if ( getInterpreter() != null ) {
	    String run[] = new String[command.length+1];
	    run[0] = getInterpreter();
	    System.arraycopy(command, 0, run, 1, command.length);
	    return Runtime.getRuntime().exec (run, aenv) ;
	} else {
	    return Runtime.getRuntime().exec (command, aenv) ;
	}
    }

    /**
     * Lookup sub-resources.
     * Accumulate the remaning path in some special state of the request.
     * <p>This allows us to implement the <code>PATH_INFO</code> 
     * CGI variable properly.
     * @param ls Current lookup state.
     * @param lr Lookup result under construction.
     * @return A boolean <strong>true</strong> if lookup should continue,
     * <strong>false</strong> otherwise.
     * @exception ProtocolException (fixme doc)
     */

    public boolean lookup(LookupState ls, LookupResult lr) 
	throws ProtocolException 
    {
	// Get the extra path information:
	String extraPath = ls.getRemainingPath(true);
	if ((extraPath == null) || extraPath.equals(""))
	    extraPath = "/";
	// Keep this path info into the request, if possible:
	Request request = (Request) ls.getRequest();
	if ( request != null )
	    request.setState(STATE_EXTRA_PATH, extraPath);
	lr.setTarget(getResource().getResourceReference());
	return super.lookup(ls, lr);
    }

    /** 
     * GET method implementation.
     * this method is splitted into two cases:
     * <p>If the resource is able to generates its form, than run the script
     * to emit the form. Otherwsie, use our super class (FileResource) ability
     * to send the file that contains the form.
     * <p>Note that there is no need to feed the underlying process with
     * data in the GET case.
     * @param request The request to handle.
     * @exception ProtocolException If processing the request failed.
     * @exception ResourceException If the resource got a fatal error.
     */
    public Reply get(Request request)
	throws ProtocolException, ResourceException
   {
       if ( ! checkGeneratesFormFlag() )
	   return super.get (request) ;
       Process       process = null ;
       try {
	   process = makeCgiCommand (request) ;
       } catch (IOException e) {
	   e.printStackTrace();
	   Reply error = request.makeReply(HTTP.NOT_FOUND) ;
	   error.setContent("The resource's script wasn't found.") ;
	   throw new HTTPException (error) ;
       }
       return handleCGIOutput (process, request) ;
   }

    /**
     * Handle the POST method according to CGI/1.1 specification.
     * The request body is sent back to the launched CGI script, as is, and
     * the script output is handled by the handleCGIOutput method.
     * @param request The request to process.
     * @exception ProtocolException If the processing failed.
     * @exception ResourceException If the resource got a fatal error.
     */
    public Reply post(Request request)
	throws ProtocolException, ResourceException
    {
	Process       process = null ;
	// Launch the CGI process:
	try {
	    process = makeCgiCommand(request) ;
	} catch (IOException ex) {
	    // The process wasn't executable, emit a errlog message:
	    String msg = ("The process "+
			  getCommand()[0] +" couldn't be executed ["+
			  ex.getMessage() + "]");
	    getServer().errlog(this, msg);
	    // Throw an internal server error:
	    Reply error = request.makeReply(HTTP.INTERNAL_SERVER_ERROR) ;
	    error.setContent("CGI script is misconfigured.");
	    throw new HTTPException (error) ;
	}
	// Now feed the process:
	try {
	    // Send the 100 status code:
	    Client client = request.getClient();
	    if ( client != null ) 
		client.sendContinue();
	    InputStream in = request.getInputStream();
	    if ( in == null ) {
		// There was no input to that CCI, close process stream
		process.getOutputStream().close();
	    } else {
		// Some input to feed the process with:
		(new ProcessFeeder(process, in)).start();
	    }
	} catch (IOException ex) {
	    // This is most probably a bad request:
	    Reply error = request.makeReply(HTTP.BAD_REQUEST);
	    error.setContent("The request didn't have a valid input.");
	    throw new HTTPException(error);
	}
	return handleCGIOutput(process, request);
    }

    /**
     * At register time, if no command, use a suitable default.
     * THis method will set the command to the identifier, if it is not
     * provided.
     * @param values Default attribute values.
     */

    public void registerResource(FramedResource resource) {
	super.registerResource(resource);
	//if no command is specified look for a file resource attached
	//and get its File absolute path if available.
	if (getCommand() == null) {
	    if (getFileResource() != null) {
		try {
		    if (getFileResource().getFile() != null) {
			String cmd[] = new String[1];
			cmd[0] = getFileResource().getFile().getAbsolutePath();
			setValue(ATTR_COMMAND, cmd);
		    }
		} catch (InvalidParentException ex) {
		    //nothing to do
		    //probably an indexer operation
		}
	    }
	}
    }
}