;;;; -*- Mode: Lisp; Syntax: ANSI-Common-Lisp; Base: 10; Package: modlisp -*-
;;;; *************************************************************************
;;;; FILE IDENTIFICATION
;;;;
;;;; Name:          sockets.lisp
;;;; Purpose:       Socket functions
;;;; Programmer:    Kevin M. Rosenberg with excerpts from portableaserve
;;;; Date Started:  Jun 2003
;;;;
;;;; $Id: sockets.lisp,v 1.2 2003/07/09 22:12:52 kevin Exp $
;;;; *************************************************************************

(in-package #:kmrcl)

(eval-when (:compile-toplevel :load-toplevel :execute)
  #+sbcl (require :sb-bsd-sockets)
  #+lispworks (require "comm")
  #+allegro (require :socket))


#+lispworks
(progn
  
(define-condition lw-stream-error (error)
  ((stream :initarg :stream
           :reader stream-error-stream)
   (action :initarg :action
           :reader stream-error-action)
   (code :initarg :code
         :reader stream-error-code)
   (identifier :initarg :identifier
               :reader stream-error-identifier))
  (:report (lambda (condition stream)
             (format stream "A stream error occured (action=~A identifier=~A code=~A stream=~S)."
                     (stream-error-action condition)
                     (stream-error-identifier condition)
                     (stream-error-code condition)
                     (stream-error-stream condition)))))

(define-condition socket-error (lw-stream-error)
  ()
  (:report (lambda (condition stream)
             (format stream "A socket error occured (action=~A identifier=~A code=~A stream=~S)."
                     (stream-error-action condition)
                     (stream-error-identifier condition)
                     (stream-error-code condition)
                     (stream-error-stream condition)))))

(defclass socket ()
    ((passive-socket :type fixnum
		     :initarg :passive-socket
		     :reader socket-os-fd)))
  
  (defclass passive-socket (socket)
    ((element-type :type (member signed-byte unsigned-byte base-char)
		   :initarg :element-type
		   :reader element-type)
     (port :type fixnum
	   :initarg :port
	   :reader local-port)))

  (defmethod print-object ((passive-socket passive-socket) stream)
    (print-unreadable-object (passive-socket stream :type t :identity nil)
      (format stream "@~d on port ~d" (socket-os-fd passive-socket) (local-port passive-socket))))

  (defclass binary-socket-stream (comm:socket-stream) ())
(defclass input-binary-socket-stream (binary-socket-stream)())
(defclass output-binary-socket-stream (binary-socket-stream)())
(defclass bidirectional-binary-socket-stream (input-binary-socket-stream output-binary-socket-stream)())

#+unix
(defun %socket-error-identifier (code)
  (case code
    (32 :x-broken-pipe)
    (98 :address-in-use)
    (99 :address-not-available)
    (100 :network-down)
    (102 :network-reset)
    (103 :connection-aborted)
    (104 :connection-reset)
    (105 :no-buffer-space)
    (108 :shutdown)
    (110 :connection-timed-out)
    (111 :connection-refused)
    (112 :host-down)
    (113 :host-unreachable)
    (otherwise :unknown)))

#+win32
(defun %socket-error-identifier (code)
  (case code
    (10048 :address-in-use)
    (10049 :address-not-available)
    (10050 :network-down)
    (10052 :network-reset)
    (10053 :connection-aborted)
    (10054 :connection-reset)
    (10055 :no-buffer-space)
    (10058 :shutdown)
    (10060 :connection-timed-out)
    (10061 :connection-refused)
    (10064 :host-down)
    (10065 :host-unreachable)
    (otherwise :unknown)))

(defun socket-error (stream error-code action format-string &rest format-args)
  (let ((code (if (numberp error-code) error-code #+unix(lw:errno-value))))
    (error 'socket-error :stream stream :code code
           :identifier (if (keywordp error-code)
                           error-code
                         (%socket-error-identifier error-code))
           :action action
           :format-control "~A occured while doing socket IO (~?)"
           :format-arguments (list 'socket-error format-string format-args))))


(defmethod comm::socket-error ((stream binary-socket-stream) error-code format-string &rest format-args)
  (apply #'socket-error stream error-code :IO format-string format-args))

(defmethod stream-input-available ((fd fixnum))
  (comm::socket-listen fd))

(defmethod stream-input-available ((stream stream::os-file-handle-stream))
  (stream-input-available (stream::os-file-handle-stream-file-handle stream)))

(defmethod stream-input-available ((stream comm:socket-stream))
  (or (comm::socket-listen (comm:socket-stream-socket stream))
      (listen stream)))

(defmethod stream-input-available ((stream passive-socket))
  (comm::socket-listen (socket-os-fd stream)))

(defun %new-passive-socket (local-port)
  (multiple-value-bind (socket error-location error-code)
      (comm::create-tcp-socket-for-service local-port)
    (cond (socket socket)
	  (t (error 'socket-error :action error-location :code error-code :identifier :unknown)))))

) ;; lispworks

#+sbcl
(defun listen-to-inet-port (&key (port 0) (kind :stream) (reuse nil))
  "Create, bind and listen to an inet socket on *:PORT.
setsockopt SO_REUSEADDR if :reuse is not nil"
  (let ((socket (make-instance 'sb-bsd-sockets:inet-socket
			       :type :stream
			       :protocol :tcp)))
    (if reuse
        (setf (sb-bsd-sockets:sockopt-reuse-address socket) t))
    (sb-bsd-sockets:socket-bind 
     socket (sb-bsd-sockets:make-inet-address "0.0.0.0") port)
    (sb-bsd-sockets:socket-listen socket 15)
    socket))

(defun create-inet-listener (port &key (format :text) (reuse-address t))
  #+cmu (ext:create-inet-listener port)
  #+allegro
  (socket:make-socket :connect :passive :local-port port :format :binary
		      :address-family 
		      (if (stringp port)
			  :file
			(if (or (null port) (integerp port))
			    :internet
			  (error "illegal value for port: ~s" port)))
		      :reuse-address reuse-address)
  #+sbcl
  (listen-to-inet-port :port port :reuse reuse-address)
  #+clisp (ext:socket-server port)
  #+lispworks
  (let ((comm::*use_so_reuseaddr* reuse-address))
    (make-instance 'passive-socket
		   :port port
		   :passive-socket (%new-passive-socket port)
		   :element-type (case format
				   (:text 'base-char))))
  )

(defun make-fd-stream (socket &key input output element-type)
  #+cmu
  (sys:make-fd-stream socket :input input :output output
		      :element-type element-type)
  #+sbcl
  (sb-bsd-sockets:socket-make-stream socket :input input :output output
				     :element-type element-type)
  #-(or cmu sbcl) (declare (ignore input output element-type))
  #-(or cmu sbcl) socket
  )


(defun accept-tcp-connection (listener)
  #+cmu
  (progn
    (mp:process-wait-until-fd-usable listener :input)
    (sys:make-fd-stream
     (nth-value 0 (ext:accept-tcp-connection listener))
     :input t :output t))
  #+sbcl
  (when (sb-sys:wait-until-fd-usable
	 (sb-bsd-sockets:socket-file-descriptor listener) :input)
    (sb-bsd-sockets:socket-make-stream 
     (sb-bsd-sockets:socket-accept listener)
     :element-type 'base-char
     :input t :output t))
  #+allegro
  (socket:accept-connection listener)
  #+clisp
  (ext:socket-accept listener)
  #+lispworks
  (progn
    (loop while (not (stream-input-available listener))
	  do (sleep 1))
    (make-instance 'bidirectional-binary-socket-stream
		   :socket (comm::get-fd-from-socket
			    (socket-os-fd listener))
		   :direction :io
		   :element-type (element-type listener)))
    
  )


(defmacro errorset (form display)
  `(handler-case
    ,form
    (error (e)
     (declare (ignorable e))
     (when ,display
       (format t "~&Error: ~A~%" e)))))

(defun close-passive-socket (socket)
  #+allegro (close socket)
  #+cmu (unix:unix-close socket)
  #+sbcl (sb-unix:unix-close
	  (sb-bsd-sockets:socket-file-descriptor socket))
  #+clisp (close socket)
  #+lispworks (comm::close-socket (socket-os-fd socket))
  )


(defun close-active-socket (socket)
  (close socket))

#+sbcl
(defun ipaddr-to-dotted (ipaddr &key values)
  "Convert from 32-bit integer to dotted string."
  (declare (type (unsigned-byte 32) ipaddr))
  (let ((a (logand #xff (ash ipaddr -24)))
	(b (logand #xff (ash ipaddr -16)))
	(c (logand #xff (ash ipaddr -8)))
	(d (logand #xff ipaddr)))
    (if values
	(values a b c d)
      (format nil "~d.~d.~d.~d" a b c d))))

#+sbcl
(defun dotted-to-ipaddr (dotted &key (errorp t))
  "Convert from dotted string to 32-bit integer."
  (declare (string dotted))
  (if errorp
      (let ((ll (string-tokens (substitute #\Space #\. dotted))))
	(+ (ash (first ll) 24) (ash (second ll) 16)
	   (ash (third ll) 8) (fourth ll)))
    (ignore-errors
	(let ((ll (string-tokens (substitute #\Space #\. dotted))))
	  (+ (ash (first ll) 24) (ash (second ll) 16)
	     (ash (third ll) 8) (fourth ll))))))

#+sbcl
(defun ipaddr-to-hostname (ipaddr &key ignore-cache)
  (when ignore-cache
    (warn ":IGNORE-CACHE keyword in IPADDR-TO-HOSTNAME not supported."))
  (sb-bsd-sockets:host-ent-name
   (sb-bsd-sockets:get-host-by-address
    (sb-bsd-sockets:make-inet-address ipaddr))))

#+sbcl
(defun lookup-hostname (host &key ignore-cache)
  (when ignore-cache
    (warn ":IGNORE-CACHE keyword in LOOKUP-HOSTNAME not supported."))
  (if (stringp host)
      (sb-bsd-sockets:host-ent-address
       (sb-bsd-sockets:get-host-by-name host))
      (dotted-to-ipaddr (ipaddr-to-dotted host))))


(defun make-active-socket (server port)
  #+allegro (socket:make-socket :remote-host server
				:remote-port port)
  #+lispworks (comm:open-tcp-stream server port)
  #+sbcl (let ((socket (make-instance 'sb-bsd-sockets:inet-socket
				      :type :stream
				      :protocol :tcp)))
	   (sb-bsd-sockets:socket-connect
	    socket (lookup-hostname server) port)
	   (sb-bsd-sockets:socket-make-stream socket
					      :input t
					      :output t
					      :element-type 'base-char))
  #+cmu 
  (sys:make-fd-stream (ext:connect-to-inet-socket host port)
		      :input t :output t :element-type 'base-char)
  )