mirror of
git://git.sv.gnu.org/emacs.git
synced 2026-02-04 22:50:59 -08:00
bc511a64f6
Most of this change is to boilerplate commentary such as license URLs. This change was prompted by ftp://ftp.gnu.org's going-away party, planned for November. Change these FTP URLs to https://ftp.gnu.org instead. Make similar changes for URLs to other organizations moving away from FTP. Also, change HTTP to HTTPS for URLs to gnu.org and fsf.org when this works, as this will further help defend against man-in-the-middle attacks (for this part I omitted the MS-DOS and MS-Windows sources and the test tarballs to keep the workload down). HTTPS is not fully working to lists.gnu.org so I left those URLs alone for now.
100 lines
3.6 KiB
EmacsLisp
100 lines
3.6 KiB
EmacsLisp
;;; url-future.el --- general futures facility for url.el -*- lexical-binding: t -*-
|
|
|
|
;; Copyright (C) 2011-2017 Free Software Foundation, Inc.
|
|
|
|
;; Author: Teodor Zlatanov <tzz@lifelogs.com>
|
|
;; Keywords: data
|
|
|
|
;; This file is part of GNU Emacs.
|
|
;;
|
|
;; GNU Emacs 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.
|
|
|
|
;; GNU Emacs 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 <https://www.gnu.org/licenses/>.
|
|
|
|
;;; Commentary:
|
|
|
|
;; Make a url-future (basically a defstruct):
|
|
;; (make-url-future :value (lambda () (calculation goes here))
|
|
;; :callback (lambda (future) (use future on success))
|
|
;; :errorback (lambda (future &rest error) (error handler)))
|
|
|
|
;; Then either call it with `url-future-call' or cancel it with
|
|
;; `url-future-cancel'. Generally the functions will return the
|
|
;; future itself, not the value it holds. Also the functions will
|
|
;; throw a url-future-already-done error if you try to call or cancel
|
|
;; a future more than once.
|
|
|
|
;; So, to get the value:
|
|
;; (when (url-future-completed-p future) (url-future-value future))
|
|
|
|
;; See `url-future-tests' and the code below for further details.
|
|
|
|
;;; Code:
|
|
|
|
(eval-when-compile (require 'cl-lib))
|
|
|
|
(cl-defstruct url-future callback errorback status value)
|
|
|
|
(define-inline url-future-done-p (url-future)
|
|
(inline-quote (url-future-status ,url-future)))
|
|
|
|
(define-inline url-future-completed-p (url-future)
|
|
(inline-quote (eq (url-future-status ,url-future) t)))
|
|
|
|
(define-inline url-future-errored-p (url-future)
|
|
(inline-quote (eq (url-future-status ,url-future) 'error)))
|
|
|
|
(define-inline url-future-cancelled-p (url-future)
|
|
(inline-quote (eq (url-future-status ,url-future) 'cancel)))
|
|
|
|
(defun url-future-finish (url-future &optional status)
|
|
(if (url-future-done-p url-future)
|
|
(signal 'error 'url-future-already-done)
|
|
(setf (url-future-status url-future) (or status t))
|
|
;; the status must be such that the future was completed
|
|
;; to run the callback
|
|
(when (url-future-completed-p url-future)
|
|
(funcall (or (url-future-callback url-future) 'ignore)
|
|
url-future))
|
|
url-future))
|
|
|
|
(defun url-future-errored (url-future errorcons)
|
|
(if (url-future-done-p url-future)
|
|
(signal 'error 'url-future-already-done)
|
|
(setf (url-future-status url-future) 'error)
|
|
(setf (url-future-value url-future) errorcons)
|
|
(funcall (or (url-future-errorback url-future) 'ignore)
|
|
url-future errorcons)))
|
|
|
|
(defun url-future-call (url-future)
|
|
(if (url-future-done-p url-future)
|
|
(signal 'error 'url-future-already-done)
|
|
(let ((ff (url-future-value url-future)))
|
|
(when (functionp ff)
|
|
(condition-case catcher
|
|
(setf (url-future-value url-future)
|
|
(funcall ff))
|
|
(error (url-future-errored url-future catcher)))
|
|
;; Unused return value.
|
|
;;; (url-future-value url-future)
|
|
))
|
|
(if (url-future-errored-p url-future)
|
|
url-future
|
|
(url-future-finish url-future))))
|
|
|
|
(defun url-future-cancel (url-future)
|
|
(if (url-future-done-p url-future)
|
|
(signal 'error 'url-future-already-done)
|
|
(url-future-finish url-future 'cancel)))
|
|
|
|
(provide 'url-future)
|
|
;;; url-future.el ends here
|