;;; ob-comint.el --- Babel Functions for Interaction with Comint Buffers -*- lexical-binding: t; -*- ;; Copyright (C) 2009-2022 Free Software Foundation, Inc. ;; Author: Eric Schulte ;; Keywords: literate programming, reproducible research, comint ;; URL: https://orgmode.org ;; 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 . ;;; Commentary: ;; These functions build on comint to ease the sending and receiving ;; of commands and results from comint buffers. ;; Note that the buffers in this file are analogous to sessions in ;; org-babel at large. ;;; Code: (require 'ob-core) (require 'org-compat) (require 'comint) (defun org-babel-comint-buffer-livep (buffer) "Check if BUFFER is a comint buffer with a live process." (let ((buffer (when buffer (get-buffer buffer)))) (and buffer (buffer-live-p buffer) (get-buffer-process buffer) buffer))) (defmacro org-babel-comint-in-buffer (buffer &rest body) "Check BUFFER and execute BODY. BUFFER is checked with `org-babel-comint-buffer-livep'. BODY is executed inside the protection of `save-excursion' and `save-match-data'." (declare (indent 1) (debug t)) `(progn (unless (org-babel-comint-buffer-livep ,buffer) (error "Buffer %s does not exist or has no process" ,buffer)) (save-match-data (with-current-buffer ,buffer (save-excursion (let ((comint-input-filter (lambda (_input) nil))) ,@body)))))) (defmacro org-babel-comint-with-output (meta &rest body) "Evaluate BODY in BUFFER and return process output. Will wait until EOE-INDICATOR appears in the output, then return all process output. If REMOVE-ECHO and FULL-BODY are present and non-nil, then strip echo'd body from the returned output. META should be a list containing the following where the last two elements are optional. (BUFFER EOE-INDICATOR REMOVE-ECHO FULL-BODY) This macro ensures that the filter is removed in case of an error or user `keyboard-quit' during execution of body." (declare (indent 1) (debug (sexp body))) (let ((buffer (nth 0 meta)) (eoe-indicator (nth 1 meta)) (remove-echo (nth 2 meta)) (full-body (nth 3 meta))) `(org-babel-comint-in-buffer ,buffer (let* ((string-buffer "") (comint-output-filter-functions (cons (lambda (text) (setq string-buffer (concat string-buffer text))) comint-output-filter-functions)) dangling-text) ;; got located, and save dangling text (goto-char (process-mark (get-buffer-process (current-buffer)))) (let ((start (point)) (end (point-max))) (setq dangling-text (buffer-substring start end)) (delete-region start end)) ;; pass FULL-BODY to process ,@body ;; wait for end-of-evaluation indicator (while (progn (goto-char comint-last-input-end) (not (save-excursion (and (re-search-forward (regexp-quote ,eoe-indicator) nil t) (re-search-forward comint-prompt-regexp nil t))))) (accept-process-output (get-buffer-process (current-buffer)))) ;; replace cut dangling text (goto-char (process-mark (get-buffer-process (current-buffer)))) (insert dangling-text) ;; remove echo'd FULL-BODY from input (when (and ,remove-echo ,full-body (string-match (replace-regexp-in-string "\n" "[\r\n]+" (regexp-quote (or ,full-body ""))) string-buffer)) (setq string-buffer (substring string-buffer (match-end 0)))) (split-string string-buffer comint-prompt-regexp))))) (defun org-babel-comint-input-command (buffer cmd) "Pass CMD to BUFFER. The input will not be echoed." (org-babel-comint-in-buffer buffer (goto-char (process-mark (get-buffer-process buffer))) (insert cmd) (comint-send-input) (org-babel-comint-wait-for-output buffer))) (defun org-babel-comint-wait-for-output (buffer) "Wait until output arrives from BUFFER. Note: this is only safe when waiting for the result of a single statement (not large blocks of code)." (org-babel-comint-in-buffer buffer (while (progn (goto-char comint-last-input-end) (not (and (re-search-forward comint-prompt-regexp nil t) (goto-char (match-beginning 0)) (string= (face-name (face-at-point)) "comint-highlight-prompt")))) (accept-process-output (get-buffer-process buffer))))) (defun org-babel-comint-eval-invisibly-and-wait-for-file (buffer file string &optional period) "Evaluate STRING in BUFFER invisibly. Don't return until FILE exists. Code in STRING must ensure that FILE exists at end of evaluation." (unless (org-babel-comint-buffer-livep buffer) (error "Buffer %s does not exist or has no process" buffer)) (when (file-exists-p file) (delete-file file)) (process-send-string (get-buffer-process buffer) (if (= (aref string (1- (length string))) ?\n) string (concat string "\n"))) (while (not (file-exists-p file)) (sit-for (or period 0.25)))) ;;; Async evaluation (defvar-local org-babel-comint-async-indicator nil "Regular expression that `org-babel-comint-async-filter' scans for. It should have 2 parenthesized expressions, e.g. \"org_babel_async_\\(start\\|end\\|file\\)_\\(.*\\)\". The first parenthesized expression determines whether the token is delimiting a result block, or whether the result is in a file. If delimiting a block, the second expression gives a UUID for the location to insert the result. Otherwise, the result is in a tmp file, and the second expression gives the file name.") (defvar-local org-babel-comint-async-buffers nil "List of Org mode buffers to check for Babel async output results.") (defvar-local org-babel-comint-async-file-callback nil "Callback to clean and insert Babel async results from a temp file. The callback function takes two arguments: the alist of params of the Babel source block, and the name of the temp file.") (defvar-local org-babel-comint-async-chunk-callback nil "Callback function to clean Babel async output results before insertion. Its single argument is a string consisting of output from the comint process. It should return a string that will be be passed to `org-babel-insert-result'.") (defvar-local org-babel-comint-async-dangling nil "Dangling piece of the last process output, in case `org-babel-comint-async-indicator' is spread across multiple comint outputs due to buffering.") (defun org-babel-comint-use-async (params) "Determine whether to use session async evaluation. PARAMS are the header arguments as passed to `org-babel-execute:lang'." (let ((async (assq :async params)) (session (assq :session params))) (and async (not org-babel-exp-reference-buffer) (not (equal (cdr async) "no")) (not (equal (cdr session) "none"))))) (defun org-babel-comint-async-filter (string) "Captures Babel async output from comint buffer back to Org mode buffers. This function is added as a hook to `comint-output-filter-functions'. STRING contains the output originally inserted into the comint buffer." ;; Remove outdated Org mode buffers (setq org-babel-comint-async-buffers (cl-loop for buf in org-babel-comint-async-buffers if (buffer-live-p buf) collect buf)) (let* ((indicator org-babel-comint-async-indicator) (org-buffers org-babel-comint-async-buffers) (file-callback org-babel-comint-async-file-callback) (combined-string (concat org-babel-comint-async-dangling string)) (new-dangling combined-string) ;; list of UUID's matched by `org-babel-comint-async-indicator' uuid-list) (with-temp-buffer (insert combined-string) (goto-char (point-min)) (while (re-search-forward indicator nil t) ;; update dangling (setq new-dangling (buffer-substring (point) (point-max))) (cond ((equal (match-string 1) "end") ;; save UUID for insertion later (push (match-string 2) uuid-list)) ((equal (match-string 1) "file") ;; insert results from tmp-file (let ((tmp-file (match-string 2))) (cl-loop for buf in org-buffers until (with-current-buffer buf (save-excursion (goto-char (point-min)) (when (search-forward tmp-file nil t) (org-babel-previous-src-block) (let* ((info (org-babel-get-src-block-info)) (params (nth 2 info)) (result-params (cdr (assq :result-params params)))) (org-babel-insert-result (funcall file-callback (nth 2 (org-babel-get-src-block-info)) tmp-file) result-params info)) t)))))))) ;; Truncate dangling to only the most recent output (when (> (length new-dangling) (length string)) (setq new-dangling string))) (setq-local org-babel-comint-async-dangling new-dangling) (when uuid-list ;; Search for results in the comint buffer (save-excursion (goto-char (point-max)) (while uuid-list (re-search-backward indicator) (when (equal (match-string 1) "end") (let* ((uuid (match-string-no-properties 2)) (res-str-raw (buffer-substring ;; move point to beginning of indicator (- (match-beginning 0) 1) ;; find the matching start indicator (cl-loop do (re-search-backward indicator) until (and (equal (match-string 1) "start") (equal (match-string 2) uuid)) finally return (+ 1 (match-end 0))))) ;; Apply callback to clean up the result (res-str (funcall org-babel-comint-async-chunk-callback res-str-raw))) ;; Search for uuid in associated org-buffers to insert results (cl-loop for buf in org-buffers until (with-current-buffer buf (save-excursion (goto-char (point-min)) (when (search-forward uuid nil t) (org-babel-previous-src-block) (let* ((info (org-babel-get-src-block-info)) (params (nth 2 info)) (result-params (cdr (assq :result-params params)))) (org-babel-insert-result res-str result-params info)) t)))) ;; Remove uuid from the list to search for (setq uuid-list (delete uuid uuid-list))))))))) (defun org-babel-comint-async-register (session-buffer org-buffer indicator-regexp chunk-callback file-callback) "Set local org-babel-comint-async variables in SESSION-BUFFER. ORG-BUFFER is added to `org-babel-comint-async-buffers' if not present. `org-babel-comint-async-indicator', `org-babel-comint-async-chunk-callback', and `org-babel-comint-async-file-callback' are set to INDICATOR-REGEXP, CHUNK-CALLBACK, and FILE-CALLBACK respectively." (org-babel-comint-in-buffer session-buffer (setq org-babel-comint-async-indicator indicator-regexp org-babel-comint-async-chunk-callback chunk-callback org-babel-comint-async-file-callback file-callback) (unless (memq org-buffer org-babel-comint-async-buffers) (setq org-babel-comint-async-buffers (cons org-buffer org-babel-comint-async-buffers))) (add-hook 'comint-output-filter-functions 'org-babel-comint-async-filter nil t))) (defmacro org-babel-comint-async-delete-dangling-and-eval (session-buffer &rest body) "Remove dangling text in SESSION-BUFFER and evaluate BODY. This is analogous to `org-babel-comint-with-output', but meant for asynchronous output, and much shorter because inserting the result is delegated to `org-babel-comint-async-filter'." (declare (indent 1) (debug t)) `(org-babel-comint-in-buffer ,session-buffer (goto-char (process-mark (get-buffer-process (current-buffer)))) (delete-region (point) (point-max)) ,@body)) (provide 'ob-comint) ;;; ob-comint.el ends here