758 lines
33 KiB
EmacsLisp
758 lines
33 KiB
EmacsLisp
;;; Interface between Emacs Lisp and Python - Lisp part. -*- emacs-lisp -*-
|
||
;;; Copyright © 2001, 2002, 2003 Progiciels Bourbeau-Pinard inc.
|
||
;;; François Pinard <pinard@iro.umontreal.ca>, 2001.
|
||
|
||
;;; 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 this program; if not, write to the Free Software Foundation,
|
||
;;; Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA. */
|
||
|
||
;;; Portability stunts.
|
||
|
||
(defvar pymacs-use-hash-tables
|
||
(and (fboundp 'make-hash-table) (fboundp 'gethash) (fboundp 'puthash))
|
||
"Set to t if hash tables are available.")
|
||
|
||
(eval-and-compile
|
||
|
||
;; pymacs-cancel-timer
|
||
(defalias 'pymacs-cancel-timer
|
||
(cond ((fboundp 'cancel-timer) 'cancel-timer)
|
||
;; XEmacs case - yet having post-gc-hook, this is unused.
|
||
((fboundp 'delete-itimer) 'delete-itimer)
|
||
(t 'ignore)))
|
||
|
||
;; pymacs-kill-without-query
|
||
(if (fboundp 'set-process-query-on-exit-flag)
|
||
(defun pymacs-kill-without-query (process)
|
||
"Tell recent Emacs how to quickly destroy PROCESS while exiting."
|
||
(set-process-query-on-exit-flag process nil))
|
||
(defalias 'pymacs-kill-without-query
|
||
(if (fboundp 'process-kill-without-query-process)
|
||
'process-kill-without-query-process
|
||
'ignore)))
|
||
|
||
;; pymacs-multibyte-string-p
|
||
(cond ((fboundp 'multibyte-string-p)
|
||
(defalias 'pymacs-multibyte-string-p 'multibyte-string-p))
|
||
((fboundp 'find-charset-string)
|
||
(defun pymacs-multibyte-string-p (string)
|
||
"Tell XEmacs if STRING should be handled as multibyte."
|
||
(not (member (find-charset-string string) '(nil (ascii))))))
|
||
(t
|
||
; Tell XEmacs that STRING is unibyte, when Mule is not around!
|
||
(defalias 'pymacs-multibyte-string-p 'ignore)))
|
||
|
||
;; pymacs-report-error
|
||
(defalias 'pymacs-report-error (symbol-function 'error))
|
||
|
||
;; pymacs-set-buffer-multibyte
|
||
(if (fboundp 'set-buffer-multibyte)
|
||
(defalias 'pymacs-set-buffer-multibyte 'set-buffer-multibyte)
|
||
(defun pymacs-set-buffer-multibyte (flag)
|
||
"For use in Emacs 20.2 or earlier. Under XEmacs: no operation."
|
||
(setq enable-multibyte-characters flag)))
|
||
|
||
;; pymacs-timerp
|
||
(defalias 'pymacs-timerp
|
||
(cond ((fboundp 'timerp) 'timerp)
|
||
; XEmacs case - yet having post-gc-hook, this is unused.
|
||
((fboundp 'itimerp) 'itimerp)
|
||
(t 'ignore)))
|
||
|
||
)
|
||
|
||
;;; Published variables and functions.
|
||
|
||
(defvar pymacs-load-path nil
|
||
"List of additional directories to search for Python modules.
|
||
The directories listed will be searched first, in the order given.")
|
||
|
||
(defvar pymacs-trace-transit '(5000 . 30000)
|
||
"Keep the communication buffer growing, for debugging.
|
||
When this variable is nil, the `*Pymacs*' communication buffer gets erased
|
||
before each communication round-trip. Setting it to `t' guarantees that
|
||
the full communication is saved, which is useful for debugging.
|
||
It could also be given as (KEEP . LIMIT): whenever the buffer exceeds LIMIT
|
||
bytes, it is reduced to approximately KEEP bytes.")
|
||
|
||
(defvar pymacs-forget-mutability nil
|
||
"Transmit copies to Python instead of Lisp handles, as much as possible.
|
||
When this variable is nil, most mutable objects are transmitted as handles.
|
||
This variable is meant to be temporarily rebound to force copies.")
|
||
|
||
(defvar pymacs-mutable-strings nil
|
||
"Prefer transmitting Lisp strings to Python as handles.
|
||
When this variable is nil, strings are transmitted as copies, and the
|
||
Python side thus has no way for modifying the original Lisp strings.
|
||
This variable is ignored whenever `forget-mutability' is set.")
|
||
|
||
(defvar pymacs-timeout-at-start 30
|
||
"Maximum reasonable time, in seconds, for starting the Pymacs helper.
|
||
A machine should be pretty loaded before one needs to increment this.")
|
||
|
||
(defvar pymacs-timeout-at-reply 5
|
||
"Expected maximum time, in seconds, to get the first line of a reply.
|
||
The status of the Pymacs helper is checked at every such timeout.")
|
||
|
||
(defvar pymacs-timeout-at-line 2
|
||
"Expected maximum time, in seconds, to get another line of a reply.
|
||
The status of the Pymacs helper is checked at every such timeout.")
|
||
|
||
(defvar pymacs-auto-restart 'ask
|
||
"Should the Pymacs helper be restarted whenever it dies?
|
||
Possible values are nil, t or ask.")
|
||
|
||
(defvar pymacs-dreadful-zombies nil
|
||
"If zombies should trigger hard errors, whenever they get called.
|
||
If `nil', calling a zombie will merely produce a diagnostic message.")
|
||
|
||
(defun pymacs-load (module &optional prefix noerror)
|
||
"Import the Python module named MODULE into Emacs.
|
||
Each function in the Python module is made available as an Emacs function.
|
||
The Lisp name of each function is the concatenation of PREFIX with
|
||
the Python name, in which underlines are replaced by dashes. If PREFIX is
|
||
not given, it defaults to MODULE followed by a dash.
|
||
If NOERROR is not nil, do not raise error when the module is not found."
|
||
(interactive
|
||
(let* ((module (read-string "Python module? "))
|
||
(default (concat (car (last (split-string module "\\."))) "-"))
|
||
(prefix (read-string (format "Prefix? [%s] " default)
|
||
nil nil default)))
|
||
(list module prefix)))
|
||
(message "Pymacs loading %s..." module)
|
||
(let ((lisp-code (pymacs-call "pymacs_load_helper" module prefix)))
|
||
(cond (lisp-code (let ((result (eval lisp-code)))
|
||
(message "Pymacs loading %s...done" module)
|
||
result))
|
||
(noerror (message "Pymacs loading %s...failed" module) nil)
|
||
(t (pymacs-report-error "Pymacs loading %s...failed" module)))))
|
||
|
||
(defun pymacs-eval (text)
|
||
"Compile TEXT as a Python expression, and return its value."
|
||
(interactive "sPython expression? ")
|
||
(let ((value (pymacs-serve-until-reply "eval" `(princ ,text))))
|
||
(when (interactive-p)
|
||
(message "%S" value))
|
||
value))
|
||
|
||
(defun pymacs-exec (text)
|
||
"Compile and execute TEXT as a sequence of Python statements.
|
||
This functionality is experimental, and does not appear to be useful."
|
||
(interactive "sPython statements? ")
|
||
(let ((value (pymacs-serve-until-reply "exec" `(princ ,text))))
|
||
(when (interactive-p)
|
||
(message "%S" value))
|
||
value))
|
||
|
||
(defun pymacs-call (function &rest arguments)
|
||
"Return the result of calling a Python function FUNCTION over ARGUMENTS.
|
||
FUNCTION is a string denoting the Python function, ARGUMENTS are separate
|
||
Lisp expressions, one per argument. Immutable Lisp constants are converted
|
||
to Python equivalents, other structures are converted into Lisp handles."
|
||
(pymacs-serve-until-reply
|
||
"eval" `(pymacs-print-for-apply ',function ',arguments)))
|
||
|
||
(defun pymacs-apply (function arguments)
|
||
"Return the result of calling a Python function FUNCTION over ARGUMENTS.
|
||
FUNCTION is a string denoting the Python function, ARGUMENTS is a list of
|
||
Lisp expressions. Immutable Lisp constants are converted to Python
|
||
equivalents, other structures are converted into Lisp handles."
|
||
(pymacs-serve-until-reply
|
||
"eval" `(pymacs-print-for-apply ',function ',arguments)))
|
||
|
||
;;; Integration details.
|
||
|
||
;; This page tries to increase the integration seamlessness of Pymacs
|
||
;; with the reminder of Emacs.
|
||
|
||
;; Module "desktop" savagely kills `*Pymacs*' in some circumstances.
|
||
;; Let's avoid such damage.
|
||
|
||
(eval-after-load 'desktop
|
||
'(push "\\*Pymacs\\*" desktop-clear-preserve-buffers))
|
||
|
||
;; Python functions and modules should ideally look like Lisp
|
||
;; functions and modules.
|
||
|
||
(when t
|
||
|
||
(defadvice documentation (around pymacs-ad-documentation activate)
|
||
;; Integration of doc-strings.
|
||
(let* ((reference (pymacs-python-reference function))
|
||
(python-doc (when reference
|
||
(pymacs-eval (format "doc_string(%s)" reference)))))
|
||
(if (or reference python-doc)
|
||
(setq ad-return-value
|
||
(concat
|
||
"It interfaces to a Python function.\n\n"
|
||
(when python-doc
|
||
(if raw python-doc (substitute-command-keys python-doc)))))
|
||
ad-do-it)))
|
||
|
||
(defun pymacs-python-reference (object)
|
||
;; Return the text reference of a Python object if possible, else nil.
|
||
(when (functionp object)
|
||
(let* ((definition (indirect-function object))
|
||
(body (and (pymacs-proper-list-p definition)
|
||
(> (length definition) 2)
|
||
(eq (car definition) 'lambda)
|
||
(cddr definition))))
|
||
(when (and body (listp (car body)) (eq (caar body) 'interactive))
|
||
;; Skip the interactive specification of a function.
|
||
(setq body (cdr body)))
|
||
(when (and body
|
||
;; Advised functions start with a string.
|
||
(not (stringp (car body)))
|
||
;; Python trampolines hold exactly one expression.
|
||
(= (length body) 1))
|
||
(let ((expression (car body)))
|
||
;; EXPRESSION might now hold something like:
|
||
;; (pymacs-apply (quote (pymacs-python . N)) ARGUMENT-LIST)
|
||
(when (and (pymacs-proper-list-p expression)
|
||
(= (length expression) 3)
|
||
(eq (car expression) 'pymacs-apply)
|
||
(eq (car (cadr expression)) 'quote))
|
||
(setq object (cadr (cadr expression))))))))
|
||
(when (eq (car-safe object) 'pymacs-python)
|
||
(format "python[%d]" (cdr object)))))
|
||
|
||
;; The following functions are experimental -- they are not satisfactory yet.
|
||
|
||
(defun pymacs-file-handler (operation &rest arguments)
|
||
;; Integration of load-file, autoload, etc.
|
||
;; Emacs might want the contents of some `MODULE.el' which does not exist,
|
||
;; while there is a `MODULE.py' or `MODULE.pyc' file in the same directory.
|
||
;; The goal is to generate a virtual contents for this `MODULE.el' file, as
|
||
;; a set of Lisp trampoline functions to the Python module functions.
|
||
;; Python modules can then be loaded or autoloaded as if they were Lisp.
|
||
(cond ((and (eq operation 'file-readable-p)
|
||
(let ((module (substring (car arguments) 0 -3)))
|
||
(or (pymacs-file-force operation arguments)
|
||
(file-readable-p (concat module ".py"))
|
||
(file-readable-p (concat module ".pyc"))))))
|
||
((and (eq operation 'load)
|
||
(not (pymacs-file-force
|
||
'file-readable-p (list (car arguments))))
|
||
(file-readable-p (car arguments)))
|
||
(let ((lisp-code (pymacs-call "pymacs_load_helper"
|
||
(substring (car arguments) 0 -3)
|
||
nil)))
|
||
(unless lisp-code
|
||
(pymacs-report-error "Python import error"))
|
||
(eval lisp-code)))
|
||
((and (eq operation 'insert-file-contents)
|
||
(not (pymacs-file-force
|
||
'file-readable-p (list (car arguments))))
|
||
(file-readable-p (car arguments)))
|
||
(let ((lisp-code (pymacs-call "pymacs_load_helper"
|
||
(substring (car arguments) 0 -3)
|
||
nil)))
|
||
(unless lisp-code
|
||
(pymacs-report-error "Python import error"))
|
||
(insert (prin1-to-string lisp-code))))
|
||
(t (pymacs-file-force operation arguments))))
|
||
|
||
(defun pymacs-file-force (operation arguments)
|
||
;; Bypass the file handler.
|
||
(let ((inhibit-file-name-handlers
|
||
(cons 'pymacs-file-handler
|
||
(and (eq inhibit-file-name-operation operation)
|
||
inhibit-file-name-handlers)))
|
||
(inhibit-file-name-operation operation))
|
||
(apply operation arguments)))
|
||
|
||
;(add-to-list 'file-name-handler-alist '("\\.el\\'" . pymacs-file-handler))
|
||
|
||
;;; Gargabe collection of Python IDs.
|
||
|
||
;; Python objects which have no Lisp representation are allocated on the
|
||
;; Python side as `python[INDEX]', and INDEX is transmitted to Emacs, with
|
||
;; the value to use on the Lisp side for it. Whenever Lisp does not need a
|
||
;; Python object anymore, it should be freed on the Python side. The
|
||
;; following variables and functions are meant to fill this duty.
|
||
|
||
(defvar pymacs-used-ids nil
|
||
"List of received IDs, currently allocated on the Python side.")
|
||
|
||
;; This is set whenever the Pymacs helper successfully starts, and is
|
||
;; also used to later detect the death of a previous helper. If
|
||
;; pymacs-use-hash-tables is unset, this variable receives `t' when
|
||
;; the helper starts, so the detection works nevertheless.
|
||
(defvar pymacs-weak-hash nil
|
||
"Weak hash table, meant to find out which IDs are still needed.")
|
||
|
||
(defvar pymacs-gc-wanted nil
|
||
"Flag that it is desirable to clean up unused IDs on the Python side.")
|
||
|
||
(defvar pymacs-gc-inhibit nil
|
||
"Flag that a new Pymacs garbage collection should just not run now.")
|
||
|
||
(defvar pymacs-gc-timer nil
|
||
"Timer to trigger Pymacs garbage collection at regular time intervals.
|
||
The timer is used only if `post-gc-hook' is not available.")
|
||
|
||
(defun pymacs-schedule-gc (&optional xemacs-list)
|
||
(unless pymacs-gc-inhibit
|
||
(setq pymacs-gc-wanted t)))
|
||
|
||
(defun pymacs-garbage-collect ()
|
||
;; Clean up unused IDs on the Python side.
|
||
(when (and pymacs-use-hash-tables (not pymacs-gc-inhibit))
|
||
(let ((pymacs-gc-inhibit t)
|
||
(pymacs-forget-mutability t)
|
||
(ids pymacs-used-ids)
|
||
used-ids unused-ids)
|
||
(while ids
|
||
(let ((id (car ids)))
|
||
(setq ids (cdr ids))
|
||
(if (gethash id pymacs-weak-hash)
|
||
(setq used-ids (cons id used-ids))
|
||
(setq unused-ids (cons id unused-ids)))))
|
||
(setq pymacs-used-ids used-ids
|
||
pymacs-gc-wanted nil)
|
||
(when unused-ids
|
||
(pymacs-apply "free_python" unused-ids)))))
|
||
|
||
(defun pymacs-defuns (arguments)
|
||
;; Take one argument, a list holding a number of items divisible by 3. The
|
||
;; first argument is an INDEX, the second is a NAME, the third is the
|
||
;; INTERACTION specification, and so forth. Register Python INDEX with a
|
||
;; function with that NAME and INTERACTION on the Lisp side. The strange
|
||
;; calling convention is to minimise quoting at call time.
|
||
(while (>= (length arguments) 3)
|
||
(let ((index (nth 0 arguments))
|
||
(name (nth 1 arguments))
|
||
(interaction (nth 2 arguments)))
|
||
(fset name (pymacs-defun index interaction))
|
||
(setq arguments (nthcdr 3 arguments)))))
|
||
|
||
(defun pymacs-defun (index interaction)
|
||
;; Register INDEX on the Lisp side with a Python object that is a function,
|
||
;; and return a lambda form calling that function. If the INTERACTION
|
||
;; specification is nil, the function is not interactive. Otherwise, the
|
||
;; function is interactive, INTERACTION is then either a string, or the
|
||
;; index of an argument-less Python function returning the argument list.
|
||
(let ((object (pymacs-python index)))
|
||
(cond ((null interaction)
|
||
`(lambda (&rest arguments)
|
||
(pymacs-apply ',object arguments)))
|
||
((stringp interaction)
|
||
`(lambda (&rest arguments)
|
||
(interactive ,interaction)
|
||
(pymacs-apply ',object arguments)))
|
||
(t `(lambda (&rest arguments)
|
||
(interactive (pymacs-call ',(pymacs-python interaction)))
|
||
(pymacs-apply ',object arguments))))))
|
||
|
||
(defun pymacs-python (index)
|
||
;; Register on the Lisp side a Python object having INDEX, and return it.
|
||
;; The result is meant to be recognised specially by `print-for-eval', and
|
||
;; in the function position by `print-for-apply'.
|
||
(let ((object (cons 'pymacs-python index)))
|
||
(when pymacs-use-hash-tables
|
||
(puthash index object pymacs-weak-hash)
|
||
(setq pymacs-used-ids (cons index pymacs-used-ids)))
|
||
object))
|
||
|
||
;;; Generating Python code.
|
||
|
||
;; Many Lisp expressions cannot fully be represented in Python, at least
|
||
;; because the object is mutable on the Lisp side. Such objects are allocated
|
||
;; somewhere into a vector of handles, and the handle index is used for
|
||
;; communication instead of the expression itself.
|
||
|
||
(defvar pymacs-lisp nil
|
||
"Vector of handles to hold transmitted expressions.")
|
||
|
||
(defvar pymacs-freed-list nil
|
||
"List of unallocated indices in Lisp.")
|
||
|
||
;; When the Python GC is done with a Lisp object, a communication occurs so to
|
||
;; free the object on the Lisp side as well.
|
||
|
||
(defun pymacs-allocate-lisp (expression)
|
||
;; This function allocates some handle for an EXPRESSION, and return its
|
||
;; index.
|
||
(unless pymacs-freed-list
|
||
(let* ((previous pymacs-lisp)
|
||
(old-size (length previous))
|
||
(new-size (if (zerop old-size) 100 (+ old-size (/ old-size 2))))
|
||
(counter new-size))
|
||
(setq pymacs-lisp (make-vector new-size nil))
|
||
(while (> counter 0)
|
||
(setq counter (1- counter))
|
||
(if (< counter old-size)
|
||
(aset pymacs-lisp counter (aref previous counter))
|
||
(setq pymacs-freed-list (cons counter pymacs-freed-list))))))
|
||
(let ((index (car pymacs-freed-list)))
|
||
(setq pymacs-freed-list (cdr pymacs-freed-list))
|
||
(aset pymacs-lisp index expression)
|
||
index))
|
||
|
||
(defun pymacs-free-lisp (indices)
|
||
;; This function is triggered from Python side for Lisp handles which lost
|
||
;; their last reference. These references should be cut on the Lisp side as
|
||
;; well, or else, the objects will never be garbage-collected.
|
||
(while indices
|
||
(let ((index (car indices)))
|
||
(aset pymacs-lisp index nil)
|
||
(setq pymacs-freed-list (cons index pymacs-freed-list)
|
||
indices (cdr indices)))))
|
||
|
||
(defun pymacs-print-for-apply (function arguments)
|
||
;; This function prints a Python expression calling FUNCTION, which is a
|
||
;; string naming a Python function, or a Python reference, over all its
|
||
;; ARGUMENTS, which are Lisp expressions.
|
||
(let ((separator "")
|
||
argument)
|
||
(if (eq (car-safe function) 'pymacs-python)
|
||
(princ (format "python[%d]" (cdr function)))
|
||
(princ function))
|
||
(princ "(")
|
||
(while arguments
|
||
(setq argument (car arguments)
|
||
arguments (cdr arguments))
|
||
(princ separator)
|
||
(setq separator ", ")
|
||
(pymacs-print-for-eval argument))
|
||
(princ ")")))
|
||
|
||
(defun pymacs-print-for-eval (expression)
|
||
;; This function prints a Python expression out of a Lisp EXPRESSION.
|
||
(let (done)
|
||
(cond ((not expression)
|
||
(princ "None")
|
||
(setq done t))
|
||
((eq expression t)
|
||
(princ "True")
|
||
(setq done t))
|
||
((numberp expression)
|
||
(princ expression)
|
||
(setq done t))
|
||
((stringp expression)
|
||
(when (or pymacs-forget-mutability
|
||
(not pymacs-mutable-strings))
|
||
(let* ((multibyte (pymacs-multibyte-string-p expression))
|
||
(text (if multibyte
|
||
(encode-coding-string expression 'utf-8)
|
||
(copy-sequence expression))))
|
||
(set-text-properties 0 (length text) nil text)
|
||
(princ (mapconcat 'identity
|
||
(split-string (prin1-to-string text) "\n")
|
||
"\\n"))
|
||
(when multibyte
|
||
(princ ".encode('ISO-8859-1').decode('UTF-8')")))
|
||
(setq done t)))
|
||
((symbolp expression)
|
||
(let ((name (symbol-name expression)))
|
||
;; The symbol can only be transmitted when in the main oblist.
|
||
(when (eq expression (intern-soft name))
|
||
(princ "lisp[")
|
||
(prin1 name)
|
||
(princ "]")
|
||
(setq done t))))
|
||
((vectorp expression)
|
||
(when pymacs-forget-mutability
|
||
(let ((limit (length expression))
|
||
(counter 0))
|
||
(princ "(")
|
||
(while (< counter limit)
|
||
(unless (zerop counter)
|
||
(princ ", "))
|
||
(pymacs-print-for-eval (aref expression counter))
|
||
(setq counter (1+ counter)))
|
||
(when (= limit 1)
|
||
(princ ","))
|
||
(princ ")")
|
||
(setq done t))))
|
||
((eq (car-safe expression) 'pymacs-python)
|
||
(princ "python[")
|
||
(princ (cdr expression))
|
||
(princ "]")
|
||
(setq done t))
|
||
((pymacs-proper-list-p expression)
|
||
(when pymacs-forget-mutability
|
||
(princ "[")
|
||
(pymacs-print-for-eval (car expression))
|
||
(while (setq expression (cdr expression))
|
||
(princ ", ")
|
||
(pymacs-print-for-eval (car expression)))
|
||
(princ "]")
|
||
(setq done t))))
|
||
(unless done
|
||
(let ((class (cond ((vectorp expression) "Vector")
|
||
((and pymacs-use-hash-tables
|
||
(hash-table-p expression))
|
||
"Table")
|
||
((bufferp expression) "Buffer")
|
||
((pymacs-proper-list-p expression) "List")
|
||
(t "Lisp"))))
|
||
(princ class)
|
||
(princ "(")
|
||
(princ (pymacs-allocate-lisp expression))
|
||
(princ ")")))))
|
||
|
||
;;; Communication protocol.
|
||
|
||
(defvar pymacs-transit-buffer nil
|
||
"Communication buffer between Emacs and Python.")
|
||
|
||
;; The principle behind the communication protocol is that it is easier to
|
||
;; generate than parse, and that each language already has its own parser.
|
||
;; So, the Emacs side generates Python text for the Python side to interpret,
|
||
;; while the Python side generates Lisp text for the Lisp side to interpret.
|
||
;; About nothing but expressions are transmitted, which are evaluated on
|
||
;; arrival. The pseudo `reply' function is meant to signal the final result
|
||
;; of a series of exchanges following a request, while the pseudo `error'
|
||
;; function is meant to explain why an exchange could not have been completed.
|
||
|
||
;; The protocol itself is rather simple, and contains human readable text
|
||
;; only. A message starts at the beginning of a line in the communication
|
||
;; buffer, either with `>' for the Lisp to Python direction, or `<' for the
|
||
;; Python to Lisp direction. This is followed by a decimal number giving the
|
||
;; length of the message text, a TAB character, and the message text itself.
|
||
;; Message direction alternates systematically between messages, it never
|
||
;; occurs that two successive messages are sent in the same direction. The
|
||
;; first message is received from the Python side, it is `(version VERSION)'.
|
||
|
||
(defun pymacs-start-services ()
|
||
;; This function gets called automatically, as needed.
|
||
(let ((buffer (get-buffer-create "*Pymacs*")))
|
||
(with-current-buffer buffer
|
||
;; Erase the buffer in case some previous incarnation of the
|
||
;; Pymacs helper died. Otherwise, the "(goto-char (point-min))"
|
||
;; below might not find the proper synchronising reply and later
|
||
;; trigger a spurious "Protocol error" diagnostic.
|
||
(erase-buffer)
|
||
(buffer-disable-undo)
|
||
(pymacs-set-buffer-multibyte nil)
|
||
(set-buffer-file-coding-system 'raw-text)
|
||
(save-match-data
|
||
;; Launch the Pymacs helper.
|
||
(let ((process
|
||
(apply 'start-process "pymacs" buffer
|
||
(let ((python (getenv "PYMACS_PYTHON")))
|
||
(if (or (null python) (equal python ""))
|
||
"python"
|
||
python))
|
||
"-c" (concat "import sys;"
|
||
" from Pymacs.pymacs import main;"
|
||
" main(*sys.argv[1:])")
|
||
(append
|
||
(and (>= emacs-major-version 24) '("-f"))
|
||
(mapcar 'expand-file-name pymacs-load-path)))))
|
||
(pymacs-kill-without-query process)
|
||
;; Receive the synchronising reply.
|
||
(while (progn
|
||
(goto-char (point-min))
|
||
(not (re-search-forward "<\\([0-9]+\\)\t" nil t)))
|
||
(unless (accept-process-output process pymacs-timeout-at-start)
|
||
(pymacs-report-error
|
||
"Pymacs helper did not start within %d seconds"
|
||
pymacs-timeout-at-start)))
|
||
(let ((marker (process-mark process))
|
||
(limit-position (+ (match-end 0)
|
||
(string-to-number (match-string 1)))))
|
||
(while (< (marker-position marker) limit-position)
|
||
(unless (accept-process-output process pymacs-timeout-at-start)
|
||
(pymacs-report-error
|
||
"Pymacs helper probably was interrupted at start")))))
|
||
;; Check that synchronisation occurred.
|
||
(goto-char (match-end 0))
|
||
(let ((reply (read (current-buffer))))
|
||
(if (and (pymacs-proper-list-p reply)
|
||
(= (length reply) 2)
|
||
(eq (car reply) 'version))
|
||
(unless (string-equal (cadr reply) "0.24-beta2")
|
||
(pymacs-report-error
|
||
"Pymacs Lisp version is 0.24-beta2, Python is %s"
|
||
(cadr reply)))
|
||
(pymacs-report-error "Pymacs got an invalid initial reply")))))
|
||
(if (not pymacs-use-hash-tables)
|
||
(setq pymacs-weak-hash t)
|
||
(when pymacs-used-ids
|
||
;; A previous Pymacs session occurred in this Emacs session,
|
||
;; some IDs hang around which do not correspond to anything on
|
||
;; the Python side. Python should not recycle such IDs for
|
||
;; new objects.
|
||
(let ((pymacs-transit-buffer buffer)
|
||
(pymacs-forget-mutability t)
|
||
(pymacs-gc-inhibit t))
|
||
(pymacs-apply "zombie_python" pymacs-used-ids))
|
||
(setq pymacs-used-ids nil))
|
||
(setq pymacs-weak-hash (make-hash-table :weakness 'value))
|
||
(if (boundp 'post-gc-hook)
|
||
(add-hook 'post-gc-hook 'pymacs-schedule-gc)
|
||
(setq pymacs-gc-timer (run-at-time 20 20 'pymacs-schedule-gc))))
|
||
;; If nothing failed, only then declare that Pymacs has started!
|
||
(setq pymacs-transit-buffer buffer)))
|
||
|
||
(defun pymacs-terminate-services ()
|
||
;; This function is mainly provided for documentation purposes.
|
||
(interactive)
|
||
(garbage-collect)
|
||
(pymacs-garbage-collect)
|
||
(when (or (not pymacs-used-ids)
|
||
(yes-or-no-p "\
|
||
Killing the Pymacs helper might create zombie objects. Kill? "))
|
||
(cond ((boundp 'post-gc-hook)
|
||
(remove-hook 'post-gc-hook 'pymacs-schedule-gc))
|
||
((pymacs-timerp pymacs-gc-timer)
|
||
(pymacs-cancel-timer pymacs-gc-timer)))
|
||
(when pymacs-transit-buffer
|
||
(kill-buffer pymacs-transit-buffer))
|
||
(setq pymacs-gc-inhibit nil
|
||
pymacs-gc-timer nil
|
||
pymacs-transit-buffer nil
|
||
pymacs-lisp nil
|
||
pymacs-freed-list nil)))
|
||
|
||
(defun pymacs-serve-until-reply (action inserter)
|
||
;; This function builds a Python request by printing ACTION and
|
||
;; evaluating INSERTER, which itself prints an argument. It then
|
||
;; sends the request to the Pymacs helper, and serves all
|
||
;; sub-requests coming from the Python side, until either a reply or
|
||
;; an error is finally received.
|
||
(unless (and pymacs-transit-buffer
|
||
(buffer-name pymacs-transit-buffer)
|
||
(get-buffer-process pymacs-transit-buffer))
|
||
(when pymacs-weak-hash
|
||
(unless (or (eq pymacs-auto-restart t)
|
||
(and (eq pymacs-auto-restart 'ask)
|
||
(yes-or-no-p "The Pymacs helper died. Restart it? ")))
|
||
(pymacs-report-error "There is no Pymacs helper!")))
|
||
(pymacs-start-services))
|
||
(when pymacs-gc-wanted
|
||
(pymacs-garbage-collect))
|
||
(let ((inhibit-quit t)
|
||
done value)
|
||
(while (not done)
|
||
(let ((form (pymacs-round-trip action inserter)))
|
||
(setq action (car form))
|
||
(when (eq action 'free)
|
||
(pymacs-free-lisp (cadr form))
|
||
(setq form (cddr form)
|
||
action (car form)))
|
||
(let* ((pair (pymacs-interruptible-eval (cadr form)))
|
||
(success (cdr pair)))
|
||
(setq value (car pair))
|
||
(cond ((eq action 'eval)
|
||
(if success
|
||
(setq action "return"
|
||
inserter `(pymacs-print-for-eval ',value))
|
||
(setq action "raise"
|
||
inserter `(let ((pymacs-forget-mutability t))
|
||
(pymacs-print-for-eval ,value)))))
|
||
((eq action 'expand)
|
||
(if success
|
||
(setq action "return"
|
||
inserter `(let ((pymacs-forget-mutability t))
|
||
(pymacs-print-for-eval ,value)))
|
||
(setq action "raise"
|
||
inserter `(let ((pymacs-forget-mutability t))
|
||
(pymacs-print-for-eval ,value)))))
|
||
((eq action 'return)
|
||
(if success
|
||
(setq done t)
|
||
(pymacs-report-error "%s" value)))
|
||
((eq action 'raise)
|
||
(if success
|
||
(pymacs-report-error "Python: %s" value)
|
||
(pymacs-report-error "%s" value)))
|
||
(t (pymacs-report-error "Protocol error: %s" form))))))
|
||
value))
|
||
|
||
(defun pymacs-round-trip (action inserter)
|
||
;; This function produces a Python request by printing and
|
||
;; evaluating INSERTER, which itself prints an argument. It sends
|
||
;; the request to the Pymacs helper, awaits for any kind of reply,
|
||
;; and returns it.
|
||
(with-current-buffer pymacs-transit-buffer
|
||
;; Possibly trim the beginning of the transit buffer.
|
||
(cond ((not pymacs-trace-transit)
|
||
(erase-buffer))
|
||
((consp pymacs-trace-transit)
|
||
(when (> (buffer-size) (cdr pymacs-trace-transit))
|
||
(let ((cut (- (buffer-size) (car pymacs-trace-transit))))
|
||
(when (> cut 0)
|
||
(save-excursion
|
||
(goto-char cut)
|
||
(unless (memq (preceding-char) '(0 ?\n))
|
||
(forward-line 1))
|
||
(delete-region (point-min) (point))))))))
|
||
;; Send the request, wait for a reply, and process it.
|
||
(let* ((process (get-buffer-process pymacs-transit-buffer))
|
||
(status (process-status process))
|
||
(marker (process-mark process))
|
||
(moving (= (point) marker))
|
||
send-position reply-position reply)
|
||
(save-excursion
|
||
(save-match-data
|
||
;; Encode request.
|
||
(setq send-position (marker-position marker))
|
||
(let ((standard-output marker))
|
||
(princ action)
|
||
(princ " ")
|
||
(eval inserter))
|
||
(goto-char marker)
|
||
(unless (= (preceding-char) ?\n)
|
||
(princ "\n" marker))
|
||
;; Send request text.
|
||
(goto-char send-position)
|
||
(insert (format ">%d\t" (- marker send-position)))
|
||
(setq reply-position (marker-position marker))
|
||
(process-send-region process send-position marker)
|
||
;; Receive reply text.
|
||
(while (and (eq status 'run)
|
||
(progn
|
||
(goto-char reply-position)
|
||
(not (re-search-forward "<\\([0-9]+\\)\t" nil t))))
|
||
(unless (accept-process-output process pymacs-timeout-at-reply)
|
||
(setq status (process-status process))))
|
||
(when (eq status 'run)
|
||
(let ((limit-position (+ (match-end 0)
|
||
(string-to-number (match-string 1)))))
|
||
(while (and (eq status 'run)
|
||
(< (marker-position marker) limit-position))
|
||
(unless (accept-process-output process pymacs-timeout-at-line)
|
||
(setq status (process-status process))))))
|
||
;; Decode reply.
|
||
(if (not (eq status 'run))
|
||
(pymacs-report-error "Pymacs helper status is `%S'" status)
|
||
(goto-char (match-end 0))
|
||
(setq reply (read (current-buffer))))))
|
||
(when (and moving (not pymacs-trace-transit))
|
||
(goto-char marker))
|
||
reply)))
|
||
|
||
(defun pymacs-interruptible-eval (expression)
|
||
;; This function produces a pair (VALUE . SUCCESS) for EXPRESSION.
|
||
;; A cautious evaluation of EXPRESSION is attempted, and any
|
||
;; error while evaluating is caught, including Emacs quit (C-g).
|
||
;; Any Emacs quit also gets forward as a SIGINT to the Pymacs handler.
|
||
;; With SUCCESS being true, VALUE is the expression value.
|
||
;; With SUCCESS being false, VALUE is an interruption diagnostic.
|
||
(condition-case info
|
||
(cons (let ((inhibit-quit nil)) (eval expression)) t)
|
||
(quit (setq quit-flag t)
|
||
(interrupt-process pymacs-transit-buffer)
|
||
(cons "*Interrupted!*" nil))
|
||
(error (cons (prin1-to-string info) nil))))
|
||
|
||
(defun pymacs-proper-list-p (expression)
|
||
;; Tell if a list is proper, id est, that it is `nil' or ends with `nil'.
|
||
(cond ((not expression))
|
||
((consp expression) (not (cdr (last expression))))))
|
||
|
||
(provide 'pymacs)
|