From 730016245b3e1c46f38bfa9e0270e00b99051afa Mon Sep 17 00:00:00 2001 From: Alexander Sulfrian Date: Tue, 15 May 2012 15:40:44 +0200 Subject: emacs.d/lisp: add edit-server.el for chrome extension --- emacs.d/lisp/edit-server.el | 576 ++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 576 insertions(+) create mode 100644 emacs.d/lisp/edit-server.el diff --git a/emacs.d/lisp/edit-server.el b/emacs.d/lisp/edit-server.el new file mode 100644 index 0000000..ceca7a7 --- /dev/null +++ b/emacs.d/lisp/edit-server.el @@ -0,0 +1,576 @@ +;;; edit-server.el --- server that responds to edit requests from Chrome + +;; Copyright (C) 2009-2011 Alex Bennee +;; Copyright (C) 2010-2011 Riccardo Murri + +;; Author: Alex Bennee +;; Maintainer: Alex Bennee +;; Version: 1.10 +;; Homepage: https://github.com/stsquad/emacs_chrome + +;; This file is not part of GNU Emacs. + +;; This file 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, or (at your option) +;; any later version. + +;; This file 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 this program. If not, see . + +;;; Commentary: + +;; This provides an edit server to respond to requests from the Chrome +;; Emacs Chrome plugin. This is my first attempt at doing something +;; with sockets in Emacs. I based it on the following examples: +;; +;; http://www.emacswiki.org/emacs/EmacsEchoServer +;; http://nullprogram.com/blog/2009/05/17/ +;; +;; To use it ensure the file is in your load-path and add something +;; like the following examples to your .emacs: +;; +;; To open pages for editing in new buffers in your existing Emacs +;; instance: +;; +;; (when (require 'edit-server nil t) +;; (setq edit-server-new-frame nil) +;; (edit-server-start)) +;; +;; To open pages for editing in new frames using a running emacs +;; started in --daemon mode: +;; +;; (when (and (require 'edit-server nil t) (daemonp)) +;; (edit-server-start)) +;; +;; Buffers are edited in `text-mode' by default; to use a different +;; major mode, change `edit-server-default-major-mode' or customize +;; `edit-server-url-major-mode-alist' to specify major modes based +;; on the remote URL: +;; +;; (setq edit-server-url-major-mode-alist +;; '(("github\\.com" . markdown-mode))) +;; +;; Alternatively, set the mode in `edit-server-start-hook'. For +;; example: +;; +;; (add-hook 'edit-server-start-hook +;; (lambda () +;; (when (string-match "github.com" (buffer-name)) +;; (markdown-mode)))) + + +;;; Code: + +;; uncomment to debug +;; (setq debug-on-error t) +;; (setq edebug-all-defs t) + +(unless (featurep 'make-network-process) + (error "Incompatible version of [X]Emacs - lacks make-network-process")) + +;;; Customization + +(defcustom edit-server-port 9292 + "Local port the edit server listens to." + :group 'edit-server + :type 'integer) + +(defcustom edit-server-host nil + "If not nil, accept connections from HOST address rather than just +localhost. This may present a security issue." + :group 'edit-server + :type 'boolean) + +(defcustom edit-server-verbose nil + "If not nil, log connections and progress also to the echo area." + :group 'edit-server + :type 'boolean) + +(defcustom edit-server-done-hook nil + "Hook run when done editing a buffer for the Emacs HTTP edit-server. +Current buffer holds the text that is about to be sent back to the client." + :group 'edit-server + :type 'hook) + +(defcustom edit-server-start-hook nil + "Hook run when starting a editing buffer. Current buffer is +the fully prepared editing buffer. Use this hook to enable +buffer-specific modes or add key bindings." + :group 'edit-server + :type 'hook) + +;; frame options + +(defcustom edit-server-new-frame t + "If not nil, edit each buffer in a new frame (and raise it)." + :group 'edit-server + :type 'boolean) + +(defcustom edit-server-new-frame-alist + '((name . "Emacs TEXTAREA") + (width . 80) + (height . 25) + (minibuffer . t) + (menu-bar-lines . t)) + "Frame parameters for new frames. See `default-frame-alist' for examples. +If nil, the new frame will use the existing `default-frame-alist' values." + :group 'edit-server + :type '(repeat (cons :format "%v" + (symbol :tag "Parameter") + (sexp :tag "Value")))) + +(defcustom edit-server-default-major-mode + 'text-mode + "The default major mode to use in editing buffers, if no other +mode is selected by `edit-server-url-major-mode-alist'." + :group 'edit-server + :type 'function) + +(defcustom edit-server-url-major-mode-alist + nil + "A-list of patterns and corresponding functions; when the first +pattern is encountered which matches `edit-server-url', the +corresponding function will be called in order to set the desired +major mode. If no pattern matches, +`edit-server-default-major-mode' will be used." + :group 'edit-server + :type '(alist :key-type (string :tag "Regexp") + :value-type (function :tag "Major mode function"))) + +(defcustom edit-server-new-frame-mode-line t + "Show the emacs frame's mode-line if set to t; hide if nil." + :group 'edit-server + :type 'boolean) + +;;; Variables + +(defconst edit-server-process-buffer-name " *edit-server*" + "Template name of the edit-server process buffers.") + +(defconst edit-server-log-buffer-name "*edit-server-log*" + "Template name of the edit-server process buffers.") + +(defconst edit-server-edit-buffer-name "TEXTAREA" + "Template name of the edit-server text editing buffers.") + +(defvar edit-server-clients () + "List of all client processes associated with the server process.") + +;; Buffer local variables +;; +;; These are all required to associate the edit buffer with the +;; correct connection to the client and allow for the buffer to be sent +;; back when ready. They are `permanent-local` to avoid being reset if +;; the buffer changes major modes. + +(defvar edit-server-proc nil + "Network process associated with the current edit.") +(make-variable-buffer-local 'edit-server-proc) +(put 'edit-server-proc 'permanent-local t) + +(defvar edit-server-frame nil + "The frame created for a new edit-server process.") +(make-variable-buffer-local 'edit-server-frame) +(put 'edit-server-frame 'permanent-local t) + +(defvar edit-server-phase nil + "Symbol indicating the state of the HTTP request parsing.") +(make-variable-buffer-local 'edit-server-phase) +(put 'edit-server-phase 'permanent-local t) + +(defvar edit-server-received nil + "Number of bytes received so far in the client buffer. +Depending on the character encoding, may be different from the buffer length.") +(make-variable-buffer-local 'edit-server-received) +(put 'edit-server-received 'permanent-local t) + +(defvar edit-server-request nil + "The HTTP request (GET, HEAD, POST) received.") +(make-variable-buffer-local 'edit-server-request) +(put 'edit-server-request 'permanent-local t) + +(defvar edit-server-content-length nil + "The value gotten from the HTTP `Content-Length' header.") +(make-variable-buffer-local 'edit-server-content-length) +(put 'edit-server-content-length 'permanent-local t) + +(defvar edit-server-url nil + "The value gotten from the HTTP `x-url' header.") +(make-variable-buffer-local 'edit-server-url) +(put 'edit-server-url 'permanent-local t) + +;;; Mode magic +;; +;; We want to re-map some of the keys to trigger edit-server-done +;; instead of the usual emacs like behaviour. However using +;; local-set-key will affect all buffers of the same mode, hence we +;; define a special (derived) mode for handling editing of text areas. + + +(defvar edit-server-edit-mode-map + (let ((map (make-sparse-keymap))) + (define-key map (kbd "C-x C-s") 'edit-server-save) + (define-key map (kbd "C-x #") 'edit-server-done) + (define-key map (kbd "C-c C-c") 'edit-server-done) + (define-key map (kbd "C-x C-c") 'edit-server-abort) + map) + "Keymap for minor mode `edit-server-edit-mode'. + +Redefine a few common Emacs keystrokes to functions that can +deal with the response to the edit-server request. + +Any of the following keys will close the buffer and send the text +to the HTTP client: C-x #, C-c C-c. + +Pressing C-x C-s will save the current state to the kill-ring. + +If any of the above isused with a prefix argument, the +unmodified text is sent back instead.") + +(define-minor-mode edit-server-edit-mode + "Minor mode enabled on buffers opened by `edit-server-accept'. + +Its sole purpose is currently to enable +`edit-server-edit-mode-map', which overrides common keystrokes to +send a response back to the client." + :group 'edit-server + :lighter " EditSrv" + :init-value nil + :keymap edit-server-edit-mode-map) + + +;; Edit Server socket code + +(defun edit-server-start (&optional verbose) + "Start the edit server. + +If argument VERBOSE is non-nil, logs all server activity to buffer +`*edit-server-log*'. When called interactivity, a prefix argument +will cause it to be verbose." + (interactive "P") + (if (or (process-status "edit-server") + (null (condition-case err + (make-network-process + :name "edit-server" + :buffer edit-server-process-buffer-name + :family 'ipv4 + :host (or edit-server-host 'local) + :service edit-server-port + :log 'edit-server-accept + :server t + :noquery t) + (file-error nil)))) + (message "An edit-server process is already running") + (setq edit-server-clients '()) + (if verbose (get-buffer-create edit-server-log-buffer-name)) + (edit-server-log nil "Created a new edit-server process"))) + +(defun edit-server-stop nil + "Stop the edit server" + (interactive) + (while edit-server-clients + (edit-server-kill-client (car edit-server-clients)) + (setq edit-server-clients (cdr edit-server-clients))) + (if (process-status "edit-server") + (delete-process "edit-server") + (message "No edit server running")) + (when (get-buffer edit-server-process-buffer-name) + (kill-buffer edit-server-process-buffer-name))) + +(defun edit-server-log (proc fmt &rest args) + "If a `*edit-server-log*' buffer exists, write STRING to it. +This is done for logging purposes. If `edit-server-verbose' is +non-nil, then STRING is also echoed to the message line." + (let ((string (apply 'format fmt args))) + (if edit-server-verbose + (message string)) + (if (get-buffer edit-server-log-buffer-name) + (with-current-buffer edit-server-log-buffer-name + (goto-char (point-max)) + (insert (current-time-string) + " " + (if (processp proc) + (concat + (buffer-name (process-buffer proc)) + ": ") + "") ; nil is not acceptable to 'insert + string) + (or (bolp) (newline)))))) + +(defun edit-server-accept (server client msg) + "Accept a new client connection." + (let ((buffer (generate-new-buffer edit-server-process-buffer-name))) + (when (fboundp 'set-buffer-multibyte) + (set-buffer-multibyte t)) ; djb + (buffer-disable-undo buffer) + (set-process-buffer client buffer) + (set-process-filter client 'edit-server-filter) + ;; kill-buffer kills the associated process + (set-process-query-on-exit-flag client nil) + (with-current-buffer buffer + (setq edit-server-phase 'wait + edit-server-received 0 + edit-server-request nil)) + (setq edit-server-content-length nil + edit-server-url nil)) + (add-to-list 'edit-server-clients client) + (edit-server-log client msg)) + +(defun edit-server-filter (proc string) + "Process data received from the client." + ;; there is no guarantee that data belonging to the same client + ;; request will arrive all in one go; therefore, we must accumulate + ;; data in the buffer and process it in different phases, which + ;; requires us to keep track of the processing state. + (with-current-buffer (process-buffer proc) + (insert string) + (setq edit-server-received + (+ edit-server-received (string-bytes string))) + (when (eq edit-server-phase 'wait) + ;; look for a complete HTTP request string + (save-excursion + (goto-char (point-min)) + (when (re-search-forward + "^\\([A-Z]+\\)\\s-+\\(\\S-+\\)\\s-+\\(HTTP/[0-9\.]+\\)\r?\n" + nil t) + (edit-server-log + proc "Got HTTP `%s' request, processing in buffer `%s'..." + (match-string 1) (current-buffer)) + (setq edit-server-request (match-string 1)) + (setq edit-server-content-length nil) + (setq edit-server-phase 'head)))) + + (when (eq edit-server-phase 'head) + ;; look for "Content-length" header + (save-excursion + (goto-char (point-min)) + (when (re-search-forward "^Content-Length:\\s-+\\([0-9]+\\)" nil t) + (setq edit-server-content-length + (string-to-number (match-string 1))))) + ;; look for "x-url" header + (save-excursion + (goto-char (point-min)) + (when (re-search-forward "^x-url: .*//\\(.*\\)/" nil t) + (setq edit-server-url (match-string 1)))) + ;; look for head/body separator + (save-excursion + (goto-char (point-min)) + (when (re-search-forward "\\(\r?\n\\)\\{2\\}" nil t) + ;; HTTP headers are pure ASCII (1 char = 1 byte), so we can subtract + ;; the buffer position from the count of received bytes + (setq edit-server-received + (- edit-server-received (- (match-end 0) (point-min)))) + ;; discard headers - keep only HTTP content in buffer + (delete-region (point-min) (match-end 0)) + (setq edit-server-phase 'body)))) + + (when (eq edit-server-phase 'body) + (if (and edit-server-content-length + (> edit-server-content-length edit-server-received)) + (edit-server-log proc + "Received %d bytes of %d ..." + edit-server-received edit-server-content-length) + ;; all content transferred - process request now + (cond + ((string= edit-server-request "POST") + ;; create editing buffer, and move content to it + (edit-server-create-edit-buffer proc)) + (t + ;; send 200 OK response to any other request + (edit-server-send-response proc "edit-server is running.\n" t))) + ;; wait for another connection to arrive + (setq edit-server-received 0) + (setq edit-server-phase 'wait))))) + +(defun edit-server-create-frame(buffer) + "Create a frame for the edit server" + (if edit-server-new-frame + (let ((new-frame + (if (memq window-system '(ns mac)) + ;; Aquamacs, Emacs NS, Emacs (experimental) Mac port + (make-frame edit-server-new-frame-alist) + (make-frame-on-display (getenv "DISPLAY") + edit-server-new-frame-alist)))) + (unless edit-server-new-frame-mode-line + (setq mode-line-format nil)) + (select-frame new-frame) + (when (and (eq window-system 'x) + (fboundp 'x-send-client-message)) + (x-send-client-message nil 0 nil + "_NET_ACTIVE_WINDOW" 32 + '(1 0 0))) + (raise-frame new-frame) + (set-window-buffer (frame-selected-window new-frame) buffer) + new-frame) + (pop-to-buffer buffer) + (raise-frame) + nil)) + +(defun edit-server-choose-major-mode () + "Use `edit-server-url-major-mode-alist' to choose a major mode +initialization function based on `edit-server-url', or fall back +to `edit-server-default-major-mode'" + (let ((pairs edit-server-url-major-mode-alist) + (mode edit-server-default-major-mode)) + (while pairs + (let ((entry (car pairs))) + (if (string-match (car entry) edit-server-url) + (setq mode (cdr entry) + pairs nil) + (setq pairs (cdr pairs))))) + (funcall mode))) + +(defun edit-server-create-edit-buffer(proc) + "Create an edit buffer, place content in it and save the network + process for the final call back" + (let ((buffer (generate-new-buffer + (or edit-server-url + edit-server-edit-buffer-name)))) + (with-current-buffer buffer + (when (fboundp 'set-buffer-multibyte) + (set-buffer-multibyte t))) ; djb + (copy-to-buffer buffer (point-min) (point-max)) + (with-current-buffer buffer + (setq edit-server-url (with-current-buffer (process-buffer proc) edit-server-url)) + (edit-server-choose-major-mode) + ;; Allow `edit-server-start-hook' to override the major mode. + ;; (re)setting the minor mode seems to clear the buffer-local + ;; variables that we depend upon for the response, so call the + ;; hooks early on + (run-hooks 'edit-server-start-hook) + (not-modified) + (add-hook 'kill-buffer-hook 'edit-server-abort* nil t) + (buffer-enable-undo) + (setq edit-server-proc proc + edit-server-frame (edit-server-create-frame buffer)) + (edit-server-edit-mode)))) + +(defun edit-server-send-response (proc &optional body close) + "Send an HTTP 200 OK response back to process PROC. +Optional second argument BODY specifies the response content: + - If nil, the HTTP response will have null content. + - If a string, the string is sent as response content. + - Any other value will cause the contents of the current + buffer to be sent. +If optional third argument CLOSE is non-nil, then process PROC +and its buffer are killed with `edit-server-kill-client'." + (interactive) + (if (processp proc) + (let ((response-header (concat + "HTTP/1.0 200 OK\n" + (format "Server: Emacs/%s\n" emacs-version) + "Date: " + (format-time-string + "%a, %d %b %Y %H:%M:%S GMT\n" + (current-time))))) + (process-send-string proc response-header) + (process-send-string proc "\n") + (cond + ((stringp body) + (process-send-string proc (encode-coding-string body 'utf-8))) + ((not body) nil) + (t + (encode-coding-region (point-min) (point-max) 'utf-8) + (process-send-region proc (point-min) (point-max)))) + (process-send-eof proc) + (when close + (edit-server-kill-client proc)) + (edit-server-log proc "Editing done, sent HTTP OK response.")) + (message "edit-server-send-response: invalid proc (bug?)"))) + +(defun edit-server-kill-client (proc) + "Kill client process PROC and remove it from the list." + (let ((procbuf (process-buffer proc))) + (delete-process proc) + (when (buffer-live-p procbuf) + (kill-buffer procbuf)) + (setq edit-server-clients (delq proc edit-server-clients)))) + +(defun edit-server-done (&optional abort nokill) + "Finish editing: send HTTP response back, close client and editing buffers. + +The current contents of the buffer are sent back to the HTTP +client, unless argument ABORT is non-nil, in which case then the +original text is sent back. +If optional second argument NOKILL is non-nil, then the editing +buffer is not killed. + +When called interactively, use prefix arg to abort editing." + (interactive "P") + ;; Do nothing if the connection is closed by the browser (tab killed, etc.) + (unless (eq (process-status edit-server-proc) 'closed) + (let ((buffer (current-buffer)) + (proc edit-server-proc) + (procbuf (process-buffer edit-server-proc))) + ;; edit-server-* vars are buffer-local, + ;; so they must be used before issuing kill-buffer + (if abort + ;; send back original content + (with-current-buffer procbuf + (run-hooks 'edit-server-done-hook) + (edit-server-send-response proc t)) + ;; send back edited content + (save-restriction + (widen) + (buffer-disable-undo) + ;; ensure any format encoding is done (like longlines) + (dolist (format buffer-file-format) + (format-encode-region (point-min) (point-max) format)) + ;; send back + (run-hooks 'edit-server-done-hook) + (edit-server-send-response edit-server-proc t) + ;; restore formats (only useful if we keep the buffer) + (dolist (format buffer-file-format) + (format-decode-region (point-min) (point-max) format)) + (buffer-enable-undo))) + (when edit-server-frame + (delete-frame edit-server-frame)) + ;; delete-frame may change the current buffer + (unless nokill + (kill-buffer buffer)) + (edit-server-kill-client proc)))) + +;; +;; There are a couple of options for handling the save +;; action. The intent is to preserve data but not finish +;; editing. There are a couple of approaches that could +;; be taken: +;; a) Use the iterative edit-server option (send a buffer +;; back to the client which then returns new request +;; to continue the session). +;; b) Back-up the edit session to a file +;; c) Save the current buffer to the kill-ring +;; +;; I've attempted to do a) a couple of times but I keep running +;; into problems which I think are emacs bugs. So for now I'll +;; just push the current buffer to the kill-ring. + +(defun edit-server-save () + "Save the current state of the edit buffer." + (interactive) + (save-restriction + (widen) + (buffer-disable-undo) + (copy-region-as-kill (point-min) (point-max)) + (buffer-enable-undo))) + +(defun edit-server-abort () + "Discard editing and send the original text back to the browser." + (interactive) + (edit-server-done t)) + +(defun edit-server-abort* () + "Discard editing and send the original text back to the browser, +but don't kill the editing buffer." + (interactive) + (edit-server-done t t)) + +(provide 'edit-server) + +;;; edit-server.el ends here -- cgit v1.2.3