my-emacs-d/elpa/async-20161010.2322/async.el
Gergely Polonkai 23962832ec Update packages
2016-10-12 10:43:45 +02:00

304 lines
11 KiB
EmacsLisp
Raw Blame History

This file contains invisible Unicode characters

This file contains invisible Unicode characters that are indistinguishable to humans but may be processed differently by a computer. If you think that this is intentional, you can safely ignore this warning. Use the Escape button to reveal them.

;;; async.el --- Asynchronous processing in Emacs -*- lexical-binding: t -*-
;; Copyright (C) 2012-2016 Free Software Foundation, Inc.
;; Author: John Wiegley <jwiegley@gmail.com>
;; Created: 18 Jun 2012
;; Version: 1.9
;; Keywords: async
;; X-URL: https://github.com/jwiegley/emacs-async
;; 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 2, 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; see the file COPYING. If not, write to the
;; Free Software Foundation, Inc., 59 Temple Place - Suite 330,
;; Boston, MA 02111-1307, USA.
;;; Commentary:
;; Adds the ability to call asynchronous functions and process with ease. See
;; the documentation for `async-start' and `async-start-process'.
;;; Code:
(defgroup async nil
"Simple asynchronous processing in Emacs"
:group 'emacs)
(defvar async-debug nil)
(defvar async-send-over-pipe t)
(defvar async-in-child-emacs nil)
(defvar async-callback nil)
(defvar async-callback-for-process nil)
(defvar async-callback-value nil)
(defvar async-callback-value-set nil)
(defvar async-current-process nil)
(defvar async--procvar nil)
(defun async-inject-variables
(include-regexp &optional predicate exclude-regexp)
"Return a `setq' form that replicates part of the calling environment.
It sets the value for every variable matching INCLUDE-REGEXP and
also PREDICATE. It will not perform injection for any variable
matching EXCLUDE-REGEXP (if present). It is intended to be used
as follows:
(async-start
`(lambda ()
(require 'smtpmail)
(with-temp-buffer
(insert ,(buffer-substring-no-properties (point-min) (point-max)))
;; Pass in the variable environment for smtpmail
,(async-inject-variables \"\\`\\(smtpmail\\|\\(user-\\)?mail\\)-\")
(smtpmail-send-it)))
'ignore)"
`(setq
,@(let (bindings)
(mapatoms
(lambda (sym)
(if (and (boundp sym)
(or (null include-regexp)
(string-match include-regexp (symbol-name sym)))
(not (string-match
(or exclude-regexp "-syntax-table\\'")
(symbol-name sym))))
(let ((value (symbol-value sym)))
(when (or (null predicate)
(funcall predicate sym))
(setq bindings (cons `(quote ,value) bindings)
bindings (cons sym bindings)))))))
bindings)))
(defalias 'async-inject-environment 'async-inject-variables)
(defun async-handle-result (func result buf)
(if (null func)
(progn
(set (make-local-variable 'async-callback-value) result)
(set (make-local-variable 'async-callback-value-set) t))
(unwind-protect
(if (and (listp result)
(eq 'async-signal (nth 0 result)))
(signal (car (nth 1 result))
(cdr (nth 1 result)))
(funcall func result))
(unless async-debug
(kill-buffer buf)))))
(defun async-when-done (proc &optional _change)
"Process sentinel used to retrieve the value from the child process."
(when (eq 'exit (process-status proc))
(with-current-buffer (process-buffer proc)
(let ((async-current-process proc))
(if (= 0 (process-exit-status proc))
(if async-callback-for-process
(if async-callback
(prog1
(funcall async-callback proc)
(unless async-debug
(kill-buffer (current-buffer))))
(set (make-local-variable 'async-callback-value) proc)
(set (make-local-variable 'async-callback-value-set) t))
(goto-char (point-max))
(backward-sexp)
(async-handle-result async-callback (read (current-buffer))
(current-buffer)))
(set (make-local-variable 'async-callback-value)
(list 'error
(format "Async process '%s' failed with exit code %d"
(process-name proc) (process-exit-status proc))))
(set (make-local-variable 'async-callback-value-set) t))))))
(defun async--receive-sexp (&optional stream)
(let ((sexp (decode-coding-string (base64-decode-string
(read stream)) 'utf-8-unix))
;; Parent expects UTF-8 encoded text.
(coding-system-for-write 'utf-8-unix))
(if async-debug
(message "Received sexp {{{%s}}}" (pp-to-string sexp)))
(setq sexp (read sexp))
(if async-debug
(message "Read sexp {{{%s}}}" (pp-to-string sexp)))
(eval sexp)))
(defun async--insert-sexp (sexp)
(let (print-level
print-length
(print-escape-nonascii t)
(print-circle t))
(prin1 sexp (current-buffer))
;; Just in case the string we're sending might contain EOF
(encode-coding-region (point-min) (point-max) 'utf-8-unix)
(base64-encode-region (point-min) (point-max) t)
(goto-char (point-min)) (insert ?\")
(goto-char (point-max)) (insert ?\" ?\n)))
(defun async--transmit-sexp (process sexp)
(with-temp-buffer
(if async-debug
(message "Transmitting sexp {{{%s}}}" (pp-to-string sexp)))
(async--insert-sexp sexp)
(process-send-region process (point-min) (point-max))))
(defun async-batch-invoke ()
"Called from the child Emacs process' command-line."
;; Make sure 'message' and 'prin1' encode stuff in UTF-8, as parent
;; process expects.
(let ((coding-system-for-write 'utf-8-unix))
(setq async-in-child-emacs t
debug-on-error async-debug)
(if debug-on-error
(prin1 (funcall
(async--receive-sexp (unless async-send-over-pipe
command-line-args-left))))
(condition-case err
(prin1 (funcall
(async--receive-sexp (unless async-send-over-pipe
command-line-args-left))))
(error
(prin1 (list 'async-signal err)))))))
(defun async-ready (future)
"Query a FUTURE to see if the ready is ready -- i.e., if no blocking
would result from a call to `async-get' on that FUTURE."
(and (memq (process-status future) '(exit signal))
(with-current-buffer (process-buffer future)
async-callback-value-set)))
(defun async-wait (future)
"Wait for FUTURE to become ready."
(while (not (async-ready future))
(sit-for 0.05)))
(defun async-get (future)
"Get the value from an asynchronously function when it is ready.
FUTURE is returned by `async-start' or `async-start-process' when
its FINISH-FUNC is nil."
(async-wait future)
(with-current-buffer (process-buffer future)
(async-handle-result #'identity async-callback-value (current-buffer))))
(defun async-message-p (value)
"Return true of VALUE is an async.el message packet."
(and (listp value)
(plist-get value :async-message)))
(defun async-send (&rest args)
"Send the given messages to the asychronous Emacs PROCESS."
(let ((args (append args '(:async-message t))))
(if async-in-child-emacs
(if async-callback
(funcall async-callback args))
(async--transmit-sexp (car args) (list 'quote (cdr args))))))
(defun async-receive ()
"Send the given messages to the asychronous Emacs PROCESS."
(async--receive-sexp))
;;;###autoload
(defun async-start-process (name program finish-func &rest program-args)
"Start the executable PROGRAM asynchronously. See `async-start'.
PROGRAM is passed PROGRAM-ARGS, calling FINISH-FUNC with the
process object when done. If FINISH-FUNC is nil, the future
object will return the process object when the program is
finished. Set DEFAULT-DIRECTORY to change PROGRAM's current
working directory."
(let* ((buf (generate-new-buffer (concat "*" name "*")))
(proc (let ((process-connection-type nil))
(apply #'start-process name buf program program-args))))
(with-current-buffer buf
(set (make-local-variable 'async-callback) finish-func)
(set-process-sentinel proc #'async-when-done)
(unless (string= name "emacs")
(set (make-local-variable 'async-callback-for-process) t))
proc)))
;;;###autoload
(defun async-start (start-func &optional finish-func)
"Execute START-FUNC (often a lambda) in a subordinate Emacs process.
When done, the return value is passed to FINISH-FUNC. Example:
(async-start
;; What to do in the child process
(lambda ()
(message \"This is a test\")
(sleep-for 3)
222)
;; What to do when it finishes
(lambda (result)
(message \"Async process done, result should be 222: %s\"
result)))
If FINISH-FUNC is nil or missing, a future is returned that can
be inspected using `async-get', blocking until the value is
ready. Example:
(let ((proc (async-start
;; What to do in the child process
(lambda ()
(message \"This is a test\")
(sleep-for 3)
222))))
(message \"I'm going to do some work here\") ;; ....
(message \"Waiting on async process, result should be 222: %s\"
(async-get proc)))
If you don't want to use a callback, and you don't care about any
return value from the child process, pass the `ignore' symbol as
the second argument (if you don't, and never call `async-get', it
will leave *emacs* process buffers hanging around):
(async-start
(lambda ()
(delete-file \"a remote file on a slow link\" nil))
'ignore)
Note: Even when FINISH-FUNC is present, a future is still
returned except that it yields no value (since the value is
passed to FINISH-FUNC). Call `async-get' on such a future always
returns nil. It can still be useful, however, as an argument to
`async-ready' or `async-wait'."
(let ((sexp start-func)
;; Subordinate Emacs will send text encoded in UTF-8.
(coding-system-for-read 'utf-8-unix))
(setq async--procvar
(async-start-process
"emacs" (file-truename
(expand-file-name invocation-name
invocation-directory))
finish-func
"-Q" "-l"
;; Using `locate-library' ensure we use the right file
;; when the .elc have been deleted.
(locate-library "async")
"-batch" "-f" "async-batch-invoke"
(if async-send-over-pipe
"<none>"
(with-temp-buffer
(async--insert-sexp (list 'quote sexp))
(buffer-string)))))
(if async-send-over-pipe
(async--transmit-sexp async--procvar (list 'quote sexp)))
async--procvar))
(defmacro async-sandbox(func)
"Evaluate FUNC in a separate Emacs process, synchronously."
`(async-get (async-start ,func)))
(provide 'async)
;;; async.el ends here