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| -rw-r--r-- | jack.el | 367 |
1 files changed, 367 insertions, 0 deletions
@@ -0,0 +1,367 @@ +;;; jack.el --- Jack Audio Connection Kit support + +;; Copyright (C) 2005,2006 Free Software Foundation, Inc. + +;; Author: Mario Lang <mlang@delysid.org> +;; Keywords: multimedia, processes + +;; 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 2, 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 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: + +;; JACK is a low-latency audio server, written for POSIX conformant +;; operating systems such as GNU/Linux and Apple's OS X. It can connect a +;; number of different applications to an audio device, as well as +;; allowing them to share audio between themselves. Its clients can run in +;; their own processes (ie. as normal applications), or they can run +;; within the JACK server (ie. as a "plugin"). +;; +;; JACK was designed from the ground up for professional audio work, and +;; its design focuses on two key areas: synchronous execution of all +;; clients, and low latency operation. +;; +;; jack.el provides a fascility for starting jackd from within Emacs. +;; It also povides convenience functions for prompting the user for +;; jack client and port names in the minibuffer, as well as the +;; functions `jack-connect' and `jack-disconnect' which can be used to +;; rearrange jack port wiring with a minimum of keystokes. + +;;; Code: + +(require 'cl) + +(defgroup jack () + "Jack Audio Connection Kit" + :group 'processes) + +(defcustom jack-rc '("~/.jackdrc" "/etc/jackd.conf") + "*JACK run control paths." + :group 'jack + :type 'repeat) + +(defcustom jack-use-jack-rc t + "*If non-nil, try to retrieve jack startup arguments from run control files +listed in `jack-rc'. If no rc file is found or this variable is set +to nil, use the Emacs variables to build the startup args." + :group 'jack + :type 'boolean) + +(defcustom jack-program (executable-find "jackd") + "*JACK executable path." + :group 'jack + :type 'file) + +(defcustom jack-sample-rate 44100 + "*Default sampling rate for JACK." + :group 'jack + :type 'integer) + +(defcustom jack-period-size 128 + "*Period size to use when launching new JACK process." + :group 'jack + :type 'integer) + +(defcustom jack-alsa-device nil + "*ALSA soundcard to use." + :group 'jack + :type '(choice (const :tag "Ask" nil) string)) + +(defun jack-read-alsa-device () + "Read an ALSA device name using the minibuffer." + (let (cards) + (with-temp-buffer + (insert-file-contents "/proc/asound/cards") + (while (not (eobp)) + (if (looking-at "^\\([0-9]\\) \\[.+\\]: \\(.+\\)\n +\\(.*\\)$") + (setq cards (append (list (cons (match-string 3) (match-string 1))) cards))) + (forward-line 1))) + (concat "hw:" (cdr (assoc (completing-read "Card: " cards nil t) cards))))) + +(defun jack-alsa-device () + (or jack-alsa-device (jack-read-alsa-device))) + +(defcustom jack-output-buffer-name "*JACK output*" + "*Output buffer name." + :group 'jack + :type 'string) + +(defun jack-args () + "Return a list of startup arguments to use. +First element is the executable path." + (or (and jack-use-jack-rc + (catch 'rc-found + (let ((files (mapcar 'expand-file-name jack-rc))) + (while files + (if (file-exists-p (car files)) + (with-temp-buffer + (insert-file-contents (car files)) + (when (> (buffer-size) 0) + (throw 'rc-found + (split-string (buffer-string) "[\n \t]+"))))) + (setq files (cdr files)))) + nil)) + (list jack-program + "-v" + "-R" + "-dalsa" + (format "-d%s" (jack-alsa-device)) + (format "-r%d" jack-sample-rate) + (format "-p%d" jack-period-size)))) + +(defcustom jack-set-rtlimits t + "*Use set_rtlimits (if available) to gain realtime priorities if -R +is given in jackd command-line." + :group 'jack + :type 'boolean) + +(defcustom jack-set-rtlimits-program (executable-find "set_rtlimits") + "*Path to set_rtlimits." + :group 'jack + :type 'file) + +(defun jack-maybe-rtlimits (args) + (if (and jack-set-rtlimits + (or (member "-R" args) (member "--realtime" args)) + (file-exists-p jack-set-rtlimits-program)) + (append (list jack-set-rtlimits-program "-r") args) + args)) + +(defvar jack-process nil) + +(defvar jack-load 0) + +(defvar jack-max-usecs 0) + +(defvar jack-spare 0) + +(defun jack-output-buffer () + (or (get-buffer jack-output-buffer-name) + (with-current-buffer (get-buffer-create jack-output-buffer-name) + (setq major-mode 'jack-mode + mode-name "JACK" + mode-line-format (copy-tree mode-line-format)) + (setcar (nthcdr 16 mode-line-format) + `(:eval (format "load:%.2f" jack-load))) + (add-hook 'kill-buffer-hook 'jack-kill nil t) + (current-buffer)))) + +(defvar jack-xruns nil) + +(defun jack-filter (proc string) + (with-current-buffer (process-buffer proc) + (let ((moving (= (point) (process-mark proc)))) + (save-excursion + (save-match-data + (if (string-match "^load = \\([^ ]+\\) max usecs: \\([^,]+\\), spare = \\(.+\\)$" string) + (setq jack-load (string-to-number (match-string 1 string)) + jack-max-usecs (string-to-number (match-string 2 string)) + jack-spare (string-to-number (match-string 3 string))) + (if (string-match "^**** alsa_pcm: xrun of at least \\([^ ]+\\) msecs$" string) + (push (string-to-number (match-string 1 string)) jack-xruns) + (goto-char (process-mark proc)) + (insert string) + (set-marker (process-mark proc) (point)))))) + (when moving (goto-char (process-mark proc)))))) + +(defun jack-running-p () + (and jack-process (processp jack-process) + (eq (process-status jack-process) 'run))) + +(defcustom jack-started-hook nil + "*Hook run when `jack-start' successfully started a new JACK intance." + :group 'jack + :type 'hook) + +(defun jack-start () + "Start the JACK process." + (interactive) + (if (jack-running-p) (error "JACK already running") + (setq jack-process + (apply 'start-process "jack" (jack-output-buffer) + (jack-maybe-rtlimits (jack-args)))) + (set-process-filter jack-process #'jack-filter) + (run-hooks 'jack-started-hook) + (switch-to-buffer (jack-output-buffer)))) + +(defun jack-kill () + "Kill the currently running JACK process." + (interactive) + (when (jack-running-p) (delete-process jack-process)) + (setq jack-process nil)) + +(defun jack-restart () + "Restart JACK." + (interactive) + (if (jack-running-p) (jack-kill)) + (sit-for 0) + (jack-start)) + +(defun jack-list () + "Retrieve a list of JACK clients/ports." + (with-temp-buffer + (call-process "jack_lsp" nil t nil "-cpl") + (goto-char (point-min)) + (let (result current-port) + (while (not (eobp)) + (cond + ((looking-at "^\\([^ \t:]+\\):\\(.+\\)$") + (let ((program (match-string 1)) + (port (match-string 2))) + (if (assoc program result) + (setcdr (assoc program result) + (append (cdr (assoc program result)) (list (setq current-port (list port))))) + (setq result + (append (list (list program (setq current-port (list port)))) result))))) + ((looking-at "^ \\([^ \t:]+\\):\\(.+\\)$") + (if (assoc 'connections (cdr current-port)) + (setcdr (assoc 'connections (cdr current-port)) + (append (cdr (assoc 'connections current-port)) + (list (list (match-string 1) (match-string 2))))) + (setcdr current-port + (append (list (list 'connections (list (match-string 1) (match-string 2)))) (cdr current-port))))) + ((looking-at "^\tproperties: \\(.+\\),$") + (setcdr current-port + (append (list (append (list 'properties) (mapcar #'intern (split-string (match-string 1) ",")))) (cdr current-port))))) + (forward-line 1)) + result))) + +(defun jack-ports (program) + (cdr (assoc program (jack-list)))) + +(defun jack-get-port-connections (program port) + (cdr (assoc 'connections (cdr (assoc port (jack-ports program)))))) + +(defun jack-get-port-properties (program port) + (cdr (assoc 'properties (cdr (assoc port (jack-ports program)))))) + +(defun jack-get-direction (program port) + (let ((props (jack-get-port-properties program port))) + (or (car (member 'output props)) + (car (member 'input props)) + (error "Neither input nor output port")))) + +(defun jack-read-program (prompt &optional predicate) + (let ((progs (if (functionp predicate) + (remove-if-not predicate (jack-list)) + (jack-list)))) + (unless progs (error "No matching JACK clients found")) + (if (< (length progs) 2) (caar progs) + (completing-read prompt progs nil t)))) + +(defun jack-unique-port-name (strings) + (let ((start "") + (maxlen (apply 'min (mapcar #'length strings)))) + (while (and (< (length start) maxlen) + (catch 'not-ok + (let ((nextchar (substring (car strings) (length start) (1+ (length start))))) + (mapc (lambda (str) + (unless (string= (concat start nextchar) (substring str 0 (1+ (length start)))) + (throw 'not-ok nil))) + strings) + t))) + (setq start (substring (car strings) 0 (1+ (length start))))) + start)) + +(defun jack-read-port (program prompt &optional predicate) + (let ((ports (if (functionp predicate) + (remove-if-not predicate (jack-ports program)) + (jack-ports program)))) + (if (< (length ports) 2) (caar ports) + (completing-read prompt ports nil t (jack-unique-port-name (mapcar 'car ports)))))) + +(defun jack-connect (from-program from-port to-program to-port) + "Connect FROM-PROGRAM's output port FROM-PORT to TO-PROGRAM's input port +TO-PORT. +If called interactively, the direction does not matter." + (interactive + (let* ((prog (jack-read-program "Connect: ")) + (port (jack-read-port prog (format "Connect %s port: " prog))) + (to-type (if (eq (jack-get-direction prog port) 'input) 'output 'input)) + (to-prog (jack-read-program + (format "Connect %s port %s to: " prog port) + (lambda (prog) + (find-if (lambda (port) + (member to-type (assoc 'properties (cdr port)))) + (cdr prog))))) + (to-port (jack-read-port + to-prog + (format "Connect %s port %s to %s port: " prog port to-prog) + (lambda (port) + (member to-type (cdr (assoc 'properties (cdr port)))))))) + (if (eq to-type 'input) + (list prog port to-prog to-port) + (list to-prog to-port prog port)))) + (let ((result (call-process "jack_connect" nil nil nil + (format "%s:%s" from-program from-port) + (format "%s:%s" to-program to-port)))) + (if (= result 0) + (message "JACK: Connected %s:%s to %s:%s" + from-program from-port to-program to-port)))) + +(defun jack-disconnect (from-program from-port to-program to-port) + "Disconnect FROM-PROGRAM's output port FROM-PORT from TO-PROGRAM's +input port TO-PORT. +If called interactively, the direction is not relevant." + (interactive + (let* ((prog (jack-read-program + "Disconnect: " + (lambda (prog) + (find-if (lambda (port) (assoc 'connections (cdr port))) + (cdr prog))))) + (port (jack-read-port prog + (format "Disconnect %s port: " prog) + (lambda (port) + (assoc 'connections (cdr port))))) + (connections (jack-get-port-connections prog port)) + (from (list prog port)) + (to (if (< (length connections) 2) + (car connections) + (let* ((to-progs (let (result) + (mapc (lambda (conn) + (if (not (member (car conn) result)) + (setq result + (append (list (car conn)) + result)))) + connections) + (mapcar #'list result))) + (to-prog (if (< (length to-progs) 2) + (caar to-progs) + (completing-read + (format "Disconnect %s port %s from: " + prog port) to-progs nil t)))) + (setq connections (remove-if-not + (lambda (conn) + (string= (car conn) to-prog)) + connections)) + (if (< (length connections) 2) + (car connections) + (let ((to-port (completing-read + (format "Disconnect %s port %s from %s port: " + prog port to-prog) + (mapcar #'cdr connections) nil t))) + (list to-prog to-port))))))) + (if (eq (jack-get-direction prog port) 'output) + (append from to) + (append to from)))) + (let ((result (call-process "jack_disconnect" nil nil nil + (format "%s:%s" from-program from-port) + (format "%s:%s" to-program to-port)))) + (if (= result 0) + (message "JACK: Disconnected %s:%s from %s:%s" + from-program from-port to-program to-port)))) + +(provide 'jack) +;;; jack.el ends here |