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diff --git a/configs/shared/emacs/.emacs.d/elpa/websocket-20180422.1716/websocket.el b/configs/shared/emacs/.emacs.d/elpa/websocket-20180422.1716/websocket.el new file mode 100644 index 000000000000..31c80dbbcd27 --- /dev/null +++ b/configs/shared/emacs/.emacs.d/elpa/websocket-20180422.1716/websocket.el @@ -0,0 +1,1070 @@ +;;; websocket.el --- Emacs WebSocket client and server -*- lexical-binding:t -*- + +;; Copyright (c) 2013, 2016-2017 Free Software Foundation, Inc. + +;; Author: Andrew Hyatt <ahyatt@gmail.com> +;; Keywords: Communication, Websocket, Server +;; Package-Version: 20180422.1716 +;; Version: 1.9 +;; Package-Requires: ((cl-lib "0.5")) +;; +;; This program 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 3 of the +;; License, or (at your option) any later version. +;; +;; This program 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 GNU Emacs. If not, see <http://www.gnu.org/licenses/>. + +;;; Commentary: +;; This implements RFC 6455, which can be found at +;; http://tools.ietf.org/html/rfc6455. +;; +;; This library contains code to connect Emacs as a client to a +;; websocket server, and for Emacs to act as a server for websocket +;; connections. +;; +;; Websockets clients are created by calling `websocket-open', which +;; returns a `websocket' struct. Users of this library use the +;; websocket struct, and can call methods `websocket-send-text', which +;; sends text over the websocket, or `websocket-send', which sends a +;; `websocket-frame' struct, enabling finer control of what is sent. +;; A callback is passed to `websocket-open' that will retrieve +;; websocket frames called from the websocket. Websockets are +;; eventually closed with `websocket-close'. +;; +;; Server functionality is similar. A server is started with +;; `websocket-server' called with a port and the callbacks to use, +;; which returns a process. The process can later be closed with +;; `websocket-server-close'. A `websocket' struct is also created +;; for every connection, and is exposed through the callbacks. + +(require 'bindat) +(require 'url-parse) +(require 'url-cookie) +(eval-when-compile (require 'cl-lib)) + +;;; Code: + +(cl-defstruct (websocket + (:constructor nil) + (:constructor websocket-inner-create)) + "A websocket structure. +This follows the W3C Websocket API, except translated to elisp +idioms. The API is implemented in both the websocket struct and +additional methods. Due to how defstruct slots are accessed, all +API methods are prefixed with \"websocket-\" and take a websocket +as an argument, so the distrinction between the struct API and +the additional helper APIs are not visible to the caller. + +A websocket struct is created with `websocket-open'. + +`ready-state' contains one of `connecting', `open', or +`closed', depending on the state of the websocket. + +The W3C API \"bufferedAmount\" call is not currently implemented, +since there is no elisp API to get the buffered amount from the +subprocess. There may, in fact, be output data buffered, +however, when the `on-message' or `on-close' callbacks are +called. + +`on-open', `on-message', `on-close', and `on-error' are described +in `websocket-open'. + +The `negotiated-extensions' slot lists the extensions accepted by +both the client and server, and `negotiated-protocols' does the +same for the protocols." + ;; API + (ready-state 'connecting) + client-data + on-open + on-message + on-close + on-error + negotiated-protocols + negotiated-extensions + (server-p nil :read-only t) + + ;; Other data - clients should not have to access this. + (url (cl-assert nil) :read-only t) + (protocols nil :read-only t) + (extensions nil :read-only t) + (conn (cl-assert nil) :read-only t) + ;; Only populated for servers, this is the server connection. + server-conn + accept-string + (inflight-input nil)) + +(defvar websocket-version "1.9" + "Version numbers of this version of websocket.el.") + +(defvar websocket-debug nil + "Set to true to output debugging info to a per-websocket buffer. +The buffer is ` *websocket URL debug*' where URL is the +URL of the connection.") + +(defconst websocket-guid "258EAFA5-E914-47DA-95CA-C5AB0DC85B11" + "The websocket GUID as defined in RFC 6455. +Do not change unless the RFC changes.") + +(defvar websocket-callback-debug-on-error nil + "If true, when an error happens in a client callback, invoke the debugger. +Having this on can cause issues with missing frames if the debugger is +exited by quitting instead of continuing, so it's best to have this set +to nil unless it is especially needed.") + +(defmacro websocket-document-function (function docstring) + "Document FUNCTION with DOCSTRING. Use this for defstruct accessor etc." + (declare (indent defun) + (doc-string 2)) + `(put ',function 'function-documentation ,docstring)) + +(websocket-document-function websocket-on-open + "Accessor for websocket on-open callback. +See `websocket-open' for details. + +\(fn WEBSOCKET)") + +(websocket-document-function websocket-on-message + "Accessor for websocket on-message callback. +See `websocket-open' for details. + +\(fn WEBSOCKET)") + +(websocket-document-function websocket-on-close + "Accessor for websocket on-close callback. +See `websocket-open' for details. + +\(fn WEBSOCKET)") + +(websocket-document-function websocket-on-error + "Accessor for websocket on-error callback. +See `websocket-open' for details. + +\(fn WEBSOCKET)") + +(defun websocket-genbytes (nbytes) + "Generate NBYTES random bytes." + (let ((s (make-string nbytes ?\s))) + (dotimes (i nbytes) + (aset s i (random 256))) + s)) + +(defun websocket-try-callback (websocket-callback callback-type websocket + &rest rest) + "Invoke function WEBSOCKET-CALLBACK with WEBSOCKET and REST args. +If an error happens, it is handled according to +`websocket-callback-debug-on-error'." + ;; This looks like it should be able to done more efficiently, but + ;; I'm not sure that's the case. We can't do it as a macro, since + ;; we want it to change whenever websocket-callback-debug-on-error + ;; changes. + (let ((args rest) + (debug-on-error websocket-callback-debug-on-error)) + (push websocket args) + (if websocket-callback-debug-on-error + (condition-case err + (apply (funcall websocket-callback websocket) args) + ((debug error) (funcall (websocket-on-error websocket) + websocket callback-type err))) + (condition-case err + (apply (funcall websocket-callback websocket) args) + (error (funcall (websocket-on-error websocket) websocket + callback-type err)))))) + +(defun websocket-genkey () + "Generate a key suitable for the websocket handshake." + (base64-encode-string (websocket-genbytes 16))) + +(defun websocket-calculate-accept (key) + "Calculate the expect value of the accept header. +This is based on the KEY from the Sec-WebSocket-Key header." + (base64-encode-string + (sha1 (concat key websocket-guid) nil nil t))) + +(defun websocket-get-bytes (s n) + "From string S, retrieve the value of N bytes. +Return the value as an unsigned integer. The value N must be a +power of 2, up to 8. + +We support getting frames up to 536870911 bytes (2^29 - 1), +approximately 537M long." + (if (= n 8) + (let* ((32-bit-parts + (bindat-get-field (bindat-unpack '((:val vec 2 u32)) s) :val)) + (cval + (logior (lsh (aref 32-bit-parts 0) 32) (aref 32-bit-parts 1)))) + (if (and (= (aref 32-bit-parts 0) 0) + (= (lsh (aref 32-bit-parts 1) -29) 0)) + cval + (signal 'websocket-unparseable-frame + "Frame value found too large to parse!"))) + ;; n is not 8 + (bindat-get-field + (condition-case _ + (bindat-unpack + `((:val + ,(cond ((= n 1) 'u8) + ((= n 2) 'u16) + ((= n 4) 'u32) + ;; This is an error with the library, + ;; not a user-facing, meaningful error. + (t (error + "websocket-get-bytes: Unknown N: %S" n))))) + s) + (args-out-of-range (signal 'websocket-unparseable-frame + (format "Frame unexpectedly shortly: %s" s)))) + :val))) + +(defun websocket-to-bytes (val nbytes) + "Encode the integer VAL in NBYTES of data. +NBYTES much be a power of 2, up to 8. + +This supports encoding values up to 536870911 bytes (2^29 - 1), +approximately 537M long." + (when (and (< nbytes 8) + (> val (expt 2 (* 8 nbytes)))) + ;; not a user-facing error, this must be caused from an error in + ;; this library + (error "websocket-to-bytes: Value %d could not be expressed in %d bytes" + val nbytes)) + (if (= nbytes 8) + (progn + (let* ((hi-32bits (lsh val -32)) + ;; This is just VAL on systems that don't have >= 32 bits. + (low-32bits (- val (lsh hi-32bits 32)))) + (when (or (> hi-32bits 0) (> (lsh low-32bits -29) 0)) + (signal 'websocket-frame-too-large val)) + (bindat-pack `((:val vec 2 u32)) + `((:val . [,hi-32bits ,low-32bits]))))) + (bindat-pack + `((:val ,(cond ((= nbytes 1) 'u8) + ((= nbytes 2) 'u16) + ((= nbytes 4) 'u32) + ;; Library error, not system error + (t (error "websocket-to-bytes: Unknown NBYTES: %S" nbytes))))) + `((:val . ,val))))) + +(defun websocket-get-opcode (s) + "Retrieve the opcode from first byte of string S." + (websocket-ensure-length s 1) + (let ((opcode (logand #xf (websocket-get-bytes s 1)))) + (cond ((= opcode 0) 'continuation) + ((= opcode 1) 'text) + ((= opcode 2) 'binary) + ((= opcode 8) 'close) + ((= opcode 9) 'ping) + ((= opcode 10) 'pong)))) + +(defun websocket-get-payload-len (s) + "Parse out the payload length from the string S. +We start at position 0, and return a cons of the payload length and how +many bytes were consumed from the string." + (websocket-ensure-length s 1) + (let* ((initial-val (logand 127 (websocket-get-bytes s 1)))) + (cond ((= initial-val 127) + (websocket-ensure-length s 9) + (cons (websocket-get-bytes (substring s 1) 8) 9)) + ((= initial-val 126) + (websocket-ensure-length s 3) + (cons (websocket-get-bytes (substring s 1) 2) 3)) + (t (cons initial-val 1))))) + +(cl-defstruct websocket-frame opcode payload length completep) + +(defun websocket-frame-text (frame) + "Given FRAME, return the payload as a utf-8 encoded string." + (cl-assert (websocket-frame-p frame)) + (decode-coding-string (websocket-frame-payload frame) 'utf-8)) + +(defun websocket-mask (key data) + "Using string KEY, mask string DATA according to the RFC. +This is used to both mask and unmask data." + ;; If we don't make the string unibyte here, a string of bytes that should be + ;; interpreted as a unibyte string will instead be interpreted as a multibyte + ;; string of the same length (for example, 6 multibyte chars for 你好 instead + ;; of the correct 6 unibyte chars, which would convert into 2 multibyte + ;; chars). + (apply + #'unibyte-string + (cl-loop for b across data + for i from 0 to (length data) + collect + (logxor (websocket-get-bytes (substring key (mod i 4)) 1) b)))) + +(defun websocket-ensure-length (s n) + "Ensure the string S has at most N bytes. +Otherwise we throw the error `websocket-incomplete-frame'." + (when (< (length s) n) + (throw 'websocket-incomplete-frame nil))) + +(defun websocket-encode-frame (frame should-mask) + "Encode the FRAME struct to the binary representation. +We mask the frame or not, depending on SHOULD-MASK." + (let* ((opcode (websocket-frame-opcode frame)) + (payload (websocket-frame-payload frame)) + (fin (websocket-frame-completep frame)) + (payloadp (and payload + (memq opcode '(continuation ping pong text binary)))) + (mask-key (when should-mask (websocket-genbytes 4)))) + (apply #'unibyte-string + (let ((val (append (list + (logior (pcase opcode + (`continuation 0) + (`text 1) + (`binary 2) + (`close 8) + (`ping 9) + (`pong 10)) + (if fin 128 0))) + (when payloadp + (list + (logior + (if should-mask 128 0) + (cond ((< (length payload) 126) (length payload)) + ((< (length payload) 65536) 126) + (t 127))))) + (when (and payloadp (>= (length payload) 126)) + (append (websocket-to-bytes + (length payload) + (cond ((< (length payload) 126) 1) + ((< (length payload) 65536) 2) + (t 8))) nil)) + (when (and payloadp should-mask) + (append mask-key nil)) + (when payloadp + (append (if should-mask (websocket-mask mask-key payload) + payload) + nil))))) + ;; We have to make sure the non-payload data is a full 32-bit frame + (if (= 1 (length val)) + (append val '(0)) val))))) + +(defun websocket-read-frame (s) + "Read from string S a `websocket-frame' struct with the contents. +This only gets complete frames. Partial frames need to wait until +the frame finishes. If the frame is not completed, return NIL." + (catch 'websocket-incomplete-frame + (websocket-ensure-length s 1) + (let* ((opcode (websocket-get-opcode s)) + (fin (logand 128 (websocket-get-bytes s 1))) + (payloadp (memq opcode '(continuation text binary ping pong))) + (payload-len (when payloadp + (websocket-get-payload-len (substring s 1)))) + (maskp (and + payloadp + (= 128 (logand 128 (websocket-get-bytes (substring s 1) 1))))) + (payload-start (when payloadp (+ (if maskp 5 1) (cdr payload-len)))) + (payload-end (when payloadp (+ payload-start (car payload-len)))) + (unmasked-payload (when payloadp + (websocket-ensure-length s payload-end) + (substring s payload-start payload-end)))) + (make-websocket-frame + :opcode opcode + :payload + (if maskp + (let ((masking-key (substring s (+ 1 (cdr payload-len)) + (+ 5 (cdr payload-len))))) + (websocket-mask masking-key unmasked-payload)) + unmasked-payload) + :length (if payloadp payload-end 1) + :completep (> fin 0))))) + +(defun websocket-format-error (err) + "Format an error message like command level does. +ERR should be a cons of error symbol and error data." + + ;; Formatting code adapted from `edebug-report-error' + (concat (or (get (car err) 'error-message) + (format "peculiar error (%s)" (car err))) + (when (cdr err) + (format ": %s" + (mapconcat #'prin1-to-string + (cdr err) ", "))))) + +(defun websocket-default-error-handler (_websocket type err) + "The default error handler used to handle errors in callbacks." + (display-warning 'websocket + (format "in callback `%S': %s" + type + (websocket-format-error err)) + :error)) + +;; Error symbols in use by the library +(put 'websocket-unsupported-protocol 'error-conditions + '(error websocket-error websocket-unsupported-protocol)) +(put 'websocket-unsupported-protocol 'error-message "Unsupported websocket protocol") +(put 'websocket-wss-needs-emacs-24 'error-conditions + '(error websocket-error websocket-unsupported-protocol + websocket-wss-needs-emacs-24)) +(put 'websocket-wss-needs-emacs-24 'error-message + "wss protocol is not supported for Emacs before version 24.") +(put 'websocket-received-error-http-response 'error-conditions + '(error websocket-error websocket-received-error-http-response)) +(put 'websocket-received-error-http-response 'error-message + "Error response received from websocket server") +(put 'websocket-invalid-header 'error-conditions + '(error websocket-error websocket-invalid-header)) +(put 'websocket-invalid-header 'error-message + "Invalid HTTP header sent") +(put 'websocket-illegal-frame 'error-conditions + '(error websocket-error websocket-illegal-frame)) +(put 'websocket-illegal-frame 'error-message + "Cannot send illegal frame to websocket") +(put 'websocket-closed 'error-conditions + '(error websocket-error websocket-closed)) +(put 'websocket-closed 'error-message + "Cannot send message to a closed websocket") +(put 'websocket-unparseable-frame 'error-conditions + '(error websocket-error websocket-unparseable-frame)) +(put 'websocket-unparseable-frame 'error-message + "Received an unparseable frame") +(put 'websocket-frame-too-large 'error-conditions + '(error websocket-error websocket-frame-too-large)) +(put 'websocket-frame-too-large 'error-message + "The frame being sent is too large for this emacs to handle") + +(defun websocket-intersect (a b) + "Simple list intersection, should function like Common Lisp's `intersection'." + (let ((result)) + (dolist (elem a (nreverse result)) + (when (member elem b) + (push elem result))))) + +(defun websocket-get-debug-buffer-create (websocket) + "Get or create the buffer corresponding to WEBSOCKET." + (let ((buf (get-buffer-create (format "*websocket %s debug*" + (websocket-url websocket))))) + (when (= 0 (buffer-size buf)) + (buffer-disable-undo buf)) + buf)) + +(defun websocket-debug (websocket msg &rest args) + "In the WEBSOCKET's debug buffer, send MSG, with format ARGS." + (when websocket-debug + (let ((buf (websocket-get-debug-buffer-create websocket))) + (save-excursion + (with-current-buffer buf + (goto-char (point-max)) + (insert "[WS] ") + (insert (apply #'format (append (list msg) args))) + (insert "\n")))))) + +(defun websocket-verify-response-code (output) + "Verify that OUTPUT contains a valid HTTP response code. +The only acceptable one to websocket is responce code 101. +A t value will be returned on success, and an error thrown +if not." + (unless (string-match "^HTTP/1.1 \\([[:digit:]]+\\)" output) + (signal 'websocket-invalid-header "Invalid HTTP status line")) + (unless (equal "101" (match-string 1 output)) + (signal 'websocket-received-error-http-response + (string-to-number (match-string 1 output)))) + t) + +(defun websocket-parse-repeated-field (output field) + "From header-containing OUTPUT, parse out the list from a +possibly repeated field." + (let ((pos 0) + (extensions)) + (while (and pos + (string-match (format "\r\n%s: \\(.*\\)\r\n" field) + output pos)) + (when (setq pos (match-end 1)) + (setq extensions (append extensions (split-string + (match-string 1 output) ", ?"))))) + extensions)) + +(defun websocket-process-frame (websocket frame) + "Using the WEBSOCKET's filter and connection, process the FRAME. +This returns a lambda that should be executed when all frames have +been processed. If the frame has a payload, the lambda has the frame +passed to the filter slot of WEBSOCKET. If the frame is a ping, +the lambda has a reply with a pong. If the frame is a close, the lambda +has connection termination." + (let ((opcode (websocket-frame-opcode frame))) + (cond ((memq opcode '(continuation text binary)) + (lambda () (websocket-try-callback 'websocket-on-message 'on-message + websocket frame))) + ((eq opcode 'ping) + (lambda () (websocket-send websocket + (make-websocket-frame + :opcode 'pong + :payload (websocket-frame-payload frame) + :completep t)))) + ((eq opcode 'close) + (lambda () (delete-process (websocket-conn websocket)))) + (t (lambda ()))))) + +(defun websocket-process-input-on-open-ws (websocket text) + "This handles input processing for both the client and server filters." + (let ((current-frame) + (processing-queue) + (start-point 0)) + (while (setq current-frame (websocket-read-frame + (substring text start-point))) + (push (websocket-process-frame websocket current-frame) processing-queue) + (cl-incf start-point (websocket-frame-length current-frame))) + (when (> (length text) start-point) + (setf (websocket-inflight-input websocket) + (substring text start-point))) + (dolist (to-process (nreverse processing-queue)) + (funcall to-process)))) + +(defun websocket-send-text (websocket text) + "To the WEBSOCKET, send TEXT as a complete frame." + (websocket-send + websocket + (make-websocket-frame :opcode 'text + :payload (encode-coding-string + text 'raw-text) + :completep t))) + +(defun websocket-check (frame) + "Check FRAME for correctness, returning true if correct." + (or + ;; Text, binary, and continuation frames need payloads + (and (memq (websocket-frame-opcode frame) '(text binary continuation)) + (websocket-frame-payload frame)) + ;; Pings and pongs may optionally have them + (memq (websocket-frame-opcode frame) '(ping pong)) + ;; And close shouldn't have any payload, and should always be complete. + (and (eq (websocket-frame-opcode frame) 'close) + (not (websocket-frame-payload frame)) + (websocket-frame-completep frame)))) + +(defun websocket-send (websocket frame) + "To the WEBSOCKET server, send the FRAME. +This will raise an error if the frame is illegal. + +The error signaled may be of type `websocket-illegal-frame' if +the frame is malformed in some way, also having the condition +type of `websocket-error'. The data associated with the signal +is the frame being sent. + +If the websocket is closed a signal `websocket-closed' is sent, +also with `websocket-error' condition. The data in the signal is +also the frame. + +The frame may be too large for this buid of Emacs, in which case +`websocket-frame-too-large' is returned, with the data of the +size of the frame which was too large to process. This also has +the `websocket-error' condition." + (unless (websocket-check frame) + (signal 'websocket-illegal-frame frame)) + (websocket-debug websocket "Sending frame, opcode: %s payload: %s" + (websocket-frame-opcode frame) + (websocket-frame-payload frame)) + (websocket-ensure-connected websocket) + (unless (websocket-openp websocket) + (signal 'websocket-closed frame)) + (process-send-string (websocket-conn websocket) + ;; We mask only when we're a client, following the spec. + (websocket-encode-frame frame (not (websocket-server-p websocket))))) + +(defun websocket-openp (websocket) + ;; FIXME: "open and either connecting or open"? I don't understand. --Stef + "Check WEBSOCKET and return non-nil if it is open, and either +connecting or open." + (and websocket + (not (eq 'close (websocket-ready-state websocket))) + (member (process-status (websocket-conn websocket)) '(open run)))) + +(defun websocket-close (websocket) + "Close WEBSOCKET and erase all the old websocket data." + (websocket-debug websocket "Closing websocket") + (websocket-try-callback 'websocket-on-close 'on-close websocket) + (when (websocket-openp websocket) + (websocket-send websocket + (make-websocket-frame :opcode 'close + :completep t)) + (setf (websocket-ready-state websocket) 'closed)) + (delete-process (websocket-conn websocket))) + +(defun websocket-ensure-connected (websocket) + "If the WEBSOCKET connection is closed, open it." + (unless (and (websocket-conn websocket) + (cl-ecase (process-status (websocket-conn websocket)) + ((run open listen) t) + ((stop exit signal closed connect failed nil) nil))) + (websocket-close websocket) + (websocket-open (websocket-url websocket) + :protocols (websocket-protocols websocket) + :extensions (websocket-extensions websocket) + :on-open (websocket-on-open websocket) + :on-message (websocket-on-message websocket) + :on-close (websocket-on-close websocket) + :on-error (websocket-on-error websocket)))) + +;;;;;;;;;;;;;;;;;;;;;; +;; Websocket client ;; +;;;;;;;;;;;;;;;;;;;;;; + +(cl-defun websocket-open (url &key protocols extensions (on-open 'identity) + (on-message (lambda (_w _f))) (on-close 'identity) + (on-error 'websocket-default-error-handler) + (nowait nil) (custom-header-alist nil)) + "Open a websocket connection to URL, returning the `websocket' struct. +The PROTOCOL argument is optional, and setting it will declare to +the server that this client supports the protocols in the list +given. We will require that the server also has to support that +protocols. + +Similar logic applies to EXTENSIONS, which is a list of conses, +the car of which is a string naming the extension, and the cdr of +which is the list of parameter strings to use for that extension. +The parameter strings are of the form \"key=value\" or \"value\". +EXTENSIONS can be NIL if none are in use. An example value would +be (\"deflate-stream\" . (\"mux\" \"max-channels=4\")). + +Cookies that are set via `url-cookie-store' will be used during +communication with the server, and cookies received from the +server will be stored in the same cookie storage that the +`url-cookie' package uses. + +Optionally you can specify +ON-OPEN, ON-MESSAGE and ON-CLOSE callbacks as well. + +The ON-OPEN callback is called after the connection is +established with the websocket as the only argument. The return +value is unused. + +The ON-MESSAGE callback is called after receiving a frame, and is +called with the websocket as the first argument and +`websocket-frame' struct as the second. The return value is +unused. + +The ON-CLOSE callback is called after the connection is closed, or +failed to open. It is called with the websocket as the only +argument, and the return value is unused. + +The ON-ERROR callback is called when any of the other callbacks +have an error. It takes the websocket as the first argument, and +a symbol as the second argument either `on-open', `on-message', +or `on-close', and the error as the third argument. Do NOT +rethrow the error, or else you may miss some websocket messages. +You similarly must not generate any other errors in this method. +If you want to debug errors, set +`websocket-callback-debug-on-error' to t, but this also can be +dangerous is the debugger is quit out of. If not specified, +`websocket-default-error-handler' is used. + +For each of these event handlers, the client code can store +arbitrary data in the `client-data' slot in the returned +websocket. + +The following errors might be thrown in this method or in +websocket processing, all of them having the error-condition +`websocket-error' in addition to their own symbol: + +`websocket-unsupported-protocol': Data in the error signal is the +protocol that is unsupported. For example, giving a URL starting +with http by mistake raises this error. + +`websocket-wss-needs-emacs-24': Trying to connect wss protocol +using Emacs < 24 raises this error. You can catch this error +also by `websocket-unsupported-protocol'. + +`websocket-received-error-http-response': Data in the error +signal is the integer error number. + +`websocket-invalid-header': Data in the error is a string +describing the invalid header received from the server. + +`websocket-unparseable-frame': Data in the error is a string +describing the problem with the frame. + +`nowait': If NOWAIT is true, return without waiting for the +connection to complete. + +`custom-headers-alist': An alist of custom headers to pass to the +server. The car is the header name, the cdr is the header value. +These are different from the extensions because it is not related +to the websocket protocol. +" + (let* ((name (format "websocket to %s" url)) + (url-struct (url-generic-parse-url url)) + (key (websocket-genkey)) + (coding-system-for-read 'binary) + (coding-system-for-write 'binary) + (conn (if (member (url-type url-struct) '("ws" "wss")) + (let* ((type (if (equal (url-type url-struct) "ws") + 'plain 'tls)) + (port (if (= 0 (url-port url-struct)) + (if (eq type 'tls) 443 80) + (url-port url-struct))) + (host (url-host url-struct))) + (if (eq type 'plain) + (make-network-process :name name :buffer nil :host host + :service port :nowait nowait) + (condition-case-unless-debug nil + (open-network-stream name nil host port :type type :nowait nowait) + (wrong-number-of-arguments + (signal 'websocket-wss-needs-emacs-24 "wss"))))) + (signal 'websocket-unsupported-protocol (url-type url-struct)))) + (websocket (websocket-inner-create + :conn conn + :url url + :on-open on-open + :on-message on-message + :on-close on-close + :on-error on-error + :protocols protocols + :extensions (mapcar 'car extensions) + :accept-string + (websocket-calculate-accept key)))) + (unless conn (error "Could not establish the websocket connection to %s" url)) + (process-put conn :websocket websocket) + (set-process-filter conn + (lambda (process output) + (let ((websocket (process-get process :websocket))) + (websocket-outer-filter websocket output)))) + (set-process-sentinel + conn + (websocket-sentinel url conn key protocols extensions custom-header-alist nowait)) + (set-process-query-on-exit-flag conn nil) + (websocket-ensure-handshake url conn key protocols extensions custom-header-alist) + websocket)) + +(defun websocket-sentinel (url conn key protocols extensions custom-header-alist nowait) + #'(lambda (process change) + (let ((websocket (process-get process :websocket))) + (websocket-debug websocket "State change to %s" change) + (let ((status (process-status process))) + (when (and nowait (eq status 'open)) + (websocket-ensure-handshake url conn key protocols extensions custom-header-alist)) + + (when (and (member status '(closed failed exit signal)) + (not (eq 'closed (websocket-ready-state websocket)))) + (websocket-try-callback 'websocket-on-close 'on-close websocket)))))) + +(defun websocket-ensure-handshake (url conn key protocols extensions custom-header-alist) + (let ((url-struct (url-generic-parse-url url)) + (websocket (process-get conn :websocket))) + (when (and (eq 'connecting (websocket-ready-state websocket)) + (eq 'open (process-status conn))) + (process-send-string conn + (format "GET %s HTTP/1.1\r\n" + (let ((path (url-filename url-struct))) + (if (> (length path) 0) path "/")))) + (websocket-debug websocket "Sending handshake, key: %s, acceptance: %s" + key (websocket-accept-string websocket)) + (process-send-string conn + (websocket-create-headers + url key protocols extensions custom-header-alist))))) + +(defun websocket-process-headers (url headers) + "On opening URL, process the HEADERS sent from the server." + (when (string-match "Set-Cookie: \(.*\)\r\n" headers) + ;; The url-current-object is assumed to be set by + ;; url-cookie-handle-set-cookie. + (let ((url-current-object (url-generic-parse-url url))) + (url-cookie-handle-set-cookie (match-string 1 headers))))) + +(defun websocket-outer-filter (websocket output) + "Filter the WEBSOCKET server's OUTPUT. +This will parse headers and process frames repeatedly until there +is no more output or the connection closes. If the websocket +connection is invalid, the connection will be closed." + (websocket-debug websocket "Received: %s" output) + (let ((start-point) + (text (concat (websocket-inflight-input websocket) output)) + (header-end-pos)) + (setf (websocket-inflight-input websocket) nil) + ;; If we've received the complete header, check to see if we've + ;; received the desired handshake. + (when (and (eq 'connecting (websocket-ready-state websocket))) + (if (and (setq header-end-pos (string-match "\r\n\r\n" text)) + (setq start-point (+ 4 header-end-pos))) + (progn + (condition-case err + (progn + (websocket-verify-response-code text) + (websocket-verify-headers websocket text) + (websocket-process-headers (websocket-url websocket) text)) + (error + (websocket-close websocket) + (signal (car err) (cdr err)))) + (setf (websocket-ready-state websocket) 'open) + (websocket-try-callback 'websocket-on-open 'on-open websocket)) + (setf (websocket-inflight-input websocket) text))) + (when (eq 'open (websocket-ready-state websocket)) + (websocket-process-input-on-open-ws + websocket (substring text (or start-point 0)))))) + +(defun websocket-verify-headers (websocket output) + "Based on WEBSOCKET's data, ensure the headers in OUTPUT are valid. +The output is assumed to have complete headers. This function +will either return t or call `error'. This has the side-effect +of populating the list of server extensions to WEBSOCKET." + (let ((accept-string + (concat "Sec-WebSocket-Accept: " (websocket-accept-string websocket)))) + (websocket-debug websocket "Checking for accept header: %s" accept-string) + (unless (string-match (regexp-quote accept-string) output) + (signal 'websocket-invalid-header + "Incorrect handshake from websocket: is this really a websocket connection?"))) + (let ((case-fold-search t)) + (websocket-debug websocket "Checking for upgrade header") + (unless (string-match "\r\nUpgrade: websocket\r\n" output) + (signal 'websocket-invalid-header + "No 'Upgrade: websocket' header found")) + (websocket-debug websocket "Checking for connection header") + (unless (string-match "\r\nConnection: upgrade\r\n" output) + (signal 'websocket-invalid-header + "No 'Connection: upgrade' header found")) + (when (websocket-protocols websocket) + (dolist (protocol (websocket-protocols websocket)) + (websocket-debug websocket "Checking for protocol match: %s" + protocol) + (let ((protocols + (if (string-match (format "\r\nSec-Websocket-Protocol: %s\r\n" + protocol) + output) + (list protocol) + (signal 'websocket-invalid-header + "Incorrect or missing protocol returned by the server.")))) + (setf (websocket-negotiated-protocols websocket) protocols)))) + (let* ((extensions (websocket-parse-repeated-field + output + "Sec-WebSocket-Extensions")) + (extra-extensions)) + (dolist (ext extensions) + (let ((x (cl-first (split-string ext "; ?")))) + (unless (or (member x (websocket-extensions websocket)) + (member x extra-extensions)) + (push x extra-extensions)))) + (when extra-extensions + (signal 'websocket-invalid-header + (format "Non-requested extensions returned by server: %S" + extra-extensions))) + (setf (websocket-negotiated-extensions websocket) extensions))) + t) + +;;;;;;;;;;;;;;;;;;;;;; +;; Websocket server ;; +;;;;;;;;;;;;;;;;;;;;;; + +(defvar websocket-server-websockets nil + "A list of current websockets live on any server.") + +(cl-defun websocket-server (port &rest plist) + "Open a websocket server on PORT. +If the plist contains a `:host' HOST pair, this value will be +used to configure the addresses the socket listens on. The symbol +`local' specifies the local host. If unspecified or nil, the +socket will listen on all addresses. + +This also takes a plist of callbacks: `:on-open', `:on-message', +`:on-close' and `:on-error', which operate exactly as documented +in the websocket client function `websocket-open'. Returns the +connection, which should be kept in order to pass to +`websocket-server-close'." + (let* ((conn (make-network-process + :name (format "websocket server on port %s" port) + :server t + :family 'ipv4 + :noquery t + :filter 'websocket-server-filter + :log 'websocket-server-accept + :filter-multibyte nil + :plist plist + :host (plist-get plist :host) + :service port))) + conn)) + +(defun websocket-server-close (conn) + "Closes the websocket, as well as all open websockets for this server." + (let ((to-delete)) + (dolist (ws websocket-server-websockets) + (when (eq (websocket-server-conn ws) conn) + (if (eq (websocket-ready-state ws) 'closed) + (unless (member ws to-delete) + (push ws to-delete)) + (websocket-close ws)))) + (dolist (ws to-delete) + (setq websocket-server-websockets (remove ws websocket-server-websockets)))) + (delete-process conn)) + +(defun websocket-server-accept (server client _message) + "Accept a new websocket connection from a client." + (let ((ws (websocket-inner-create + :server-conn server + :conn client + :url client + :server-p t + :on-open (or (process-get server :on-open) 'identity) + :on-message (or (process-get server :on-message) (lambda (_ws _frame))) + :on-close (let ((user-method + (or (process-get server :on-close) 'identity))) + (lambda (ws) + (setq websocket-server-websockets + (remove ws websocket-server-websockets)) + (funcall user-method ws))) + :on-error (or (process-get server :on-error) + 'websocket-default-error-handler) + :protocols (process-get server :protocol) + :extensions (mapcar 'car (process-get server :extensions))))) + (unless (member ws websocket-server-websockets) + (push ws websocket-server-websockets)) + (process-put client :websocket ws) + (set-process-coding-system client 'binary 'binary) + (set-process-sentinel client + (lambda (process change) + (let ((websocket (process-get process :websocket))) + (websocket-debug websocket "State change to %s" change) + (when (and + (member (process-status process) '(closed failed exit signal)) + (not (eq 'closed (websocket-ready-state websocket)))) + (websocket-try-callback 'websocket-on-close 'on-close websocket))))))) + +(defun websocket-create-headers (url key protocol extensions custom-headers-alist) + "Create connections headers for the given URL, KEY, PROTOCOL, and EXTENSIONS. +Additionally, the CUSTOM-HEADERS-ALIST is passed from the client. +All these parameters are defined as in `websocket-open'." + (let* ((parsed-url (url-generic-parse-url url)) + (host-port (if (url-port-if-non-default parsed-url) + (format "%s:%s" (url-host parsed-url) (url-port parsed-url)) + (url-host parsed-url))) + (cookie-header (url-cookie-generate-header-lines + host-port (car (url-path-and-query parsed-url)) + (equal (url-type parsed-url) "wss")))) + (format (concat "Host: %s\r\n" + "Upgrade: websocket\r\n" + "Connection: Upgrade\r\n" + "Sec-WebSocket-Key: %s\r\n" + "Sec-WebSocket-Version: 13\r\n" + (when protocol + (concat + (mapconcat + (lambda (protocol) + (format "Sec-WebSocket-Protocol: %s" protocol)) + protocol "\r\n") + "\r\n")) + (when extensions + (format "Sec-WebSocket-Extensions: %s\r\n" + (mapconcat + (lambda (ext) + (concat + (car ext) + (when (cdr ext) "; ") + (when (cdr ext) + (mapconcat 'identity (cdr ext) "; ")))) + extensions ", "))) + (when cookie-header cookie-header) + (concat (mapconcat (lambda (cons) (format "%s: %s" (car cons) (cdr cons))) + custom-headers-alist "\r\n") + (when custom-headers-alist "\r\n")) + "\r\n") + host-port + key + protocol))) + +(defun websocket-get-server-response (websocket client-protocols client-extensions) + "Get the websocket response from client WEBSOCKET." + (let ((separator "\r\n")) + (concat "HTTP/1.1 101 Switching Protocols" separator + "Upgrade: websocket" separator + "Connection: Upgrade" separator + "Sec-WebSocket-Accept: " + (websocket-accept-string websocket) separator + (let ((protocols + (websocket-intersect client-protocols + (websocket-protocols websocket)))) + (when protocols + (concat + (mapconcat + (lambda (protocol) (format "Sec-WebSocket-Protocol: %s" + protocol)) protocols separator) + separator))) + (let ((extensions (websocket-intersect + client-extensions + (websocket-extensions websocket)))) + (when extensions + (concat + (mapconcat + (lambda (extension) (format "Sec-Websocket-Extensions: %s" + extension)) extensions separator) + separator))) + separator))) + +(defun websocket-server-filter (process output) + "This acts on all OUTPUT from websocket clients PROCESS." + (let* ((ws (process-get process :websocket)) + (text (concat (websocket-inflight-input ws) output))) + (setf (websocket-inflight-input ws) nil) + (cond ((eq (websocket-ready-state ws) 'connecting) + ;; check for connection string + (let ((end-of-header-pos + (let ((pos (string-match "\r\n\r\n" text))) + (when pos (+ 4 pos))))) + (if end-of-header-pos + (progn + (let ((header-info (websocket-verify-client-headers text))) + (if header-info + (progn (setf (websocket-accept-string ws) + (websocket-calculate-accept + (plist-get header-info :key))) + (process-send-string + process + (websocket-get-server-response + ws (plist-get header-info :protocols) + (plist-get header-info :extensions))) + (setf (websocket-ready-state ws) 'open) + (websocket-try-callback 'websocket-on-open + 'on-open ws)) + (message "Invalid client headers found in: %s" output) + (process-send-string process "HTTP/1.1 400 Bad Request\r\n\r\n") + (websocket-close ws))) + (when (> (length text) (+ 1 end-of-header-pos)) + (websocket-server-filter process (substring + text + end-of-header-pos)))) + (setf (websocket-inflight-input ws) text)))) + ((eq (websocket-ready-state ws) 'open) + (websocket-process-input-on-open-ws ws text)) + ((eq (websocket-ready-state ws) 'closed) + (message "WARNING: Should not have received further input on closed websocket"))))) + +(defun websocket-verify-client-headers (output) + "Verify the headers from the WEBSOCKET client connection in OUTPUT. +Unlike `websocket-verify-headers', this is a quieter routine. We +don't want to error due to a bad client, so we just print out +messages and a plist containing `:key', the websocket key, +`:protocols' and `:extensions'." + (cl-block nil + (let ((case-fold-search t) + (plist)) + (unless (string-match "HTTP/1.1" output) + (message "Websocket client connection: HTTP/1.1 not found") + (cl-return nil)) + (unless (string-match "^Host: " output) + (message "Websocket client connection: Host header not found") + (cl-return nil)) + (unless (string-match "^Upgrade: websocket\r\n" output) + (message "Websocket client connection: Upgrade: websocket not found") + (cl-return nil)) + (if (string-match "^Sec-WebSocket-Key: \\([[:graph:]]+\\)\r\n" output) + (setq plist (plist-put plist :key (match-string 1 output))) + (message "Websocket client connect: No key sent") + (cl-return nil)) + (unless (string-match "^Sec-WebSocket-Version: 13" output) + (message "Websocket client connect: Websocket version 13 not found") + (cl-return nil)) + (when (string-match "^Sec-WebSocket-Protocol:" output) + (setq plist (plist-put plist :protocols (websocket-parse-repeated-field + output + "Sec-Websocket-Protocol")))) + (when (string-match "^Sec-WebSocket-Extensions:" output) + (setq plist (plist-put plist :extensions (websocket-parse-repeated-field + output + "Sec-Websocket-Extensions")))) + plist))) + +(provide 'websocket) + +;;; websocket.el ends here |