>From 0c98e87ba18493857f4d0d63f0e00bbefc152c93 Mon Sep 17 00:00:00 2001
From: "F. Jason Park" <jp@neverwas.me>
Date: Sun, 10 Apr 2022 19:50:55 -0700
Subject: [PATCH 0/4] *** NOT A PATCH ***

*** BLURB HERE ***

F. Jason Park (4):
  Display error message on incomplete ERC DCC transfer
  Don't send reports in erc-dcc-get-filter when nested
  Allow matching against string values in erc-dcc-member
  Allow running erc-dcc GET operations in a subprocess

 lisp/erc/erc-dcc.el | 117 ++++++++++++++++++++++++++++++++++----------
 1 file changed, 91 insertions(+), 26 deletions(-)

Interdiff:
diff --git a/lisp/erc/erc-dcc.el b/lisp/erc/erc-dcc.el
index c6871aefd3..d8452f2661 100644
--- a/lisp/erc/erc-dcc.el
+++ b/lisp/erc/erc-dcc.el
@@ -897,10 +897,7 @@ erc-dcc-receive-cache
 
 (defvar-local erc-dcc-file-name nil)
 
-(defun erc-dcc-get-file (entry file parent-proc)
-  "Set up a transfer from the remote client to the local over a TCP connection.
-This involves setting up a process filter and a process sentinel,
-and making the connection."
+(defun erc-dcc--get-file (entry file parent-proc)
   (let* ((buffer (generate-new-buffer (file-name-nondirectory file)))
          proc)
     (with-current-buffer buffer
@@ -938,6 +935,71 @@ erc-dcc-get-file
       (setq erc-dcc-entry-data (plist-put (plist-put entry :peer proc)
                                           :start-time (erc-current-time))))))
 
+(defcustom erc-dcc-get-use-subprocess nil
+  "If non-nil, run GET (receive) operations in a subordinate Emacs."
+  :package-version '(ERC . "5.4.1") ; FIXME make this honest
+  :type 'boolean)
+
+(defun erc-dcc--get-display-messages (&rest args)
+  (pcase-let ((`(,_parsed ,_type ,_buffer ,msg . ,rest) args))
+    (message (apply #'erc-format-message msg rest))))
+
+(defun erc-dcc--get-file-subprocess-sentinel (proc _event)
+  (with-current-buffer (process-buffer proc)
+    (widen)
+    (goto-char (point-max))
+    (while (and (not (looking-at (concat "DCC: " erc-dcc-file-name ":")))
+                (zerop (forward-line -1))))
+    (when (and (search-forward erc-dcc-file-name nil t)
+               (search-forward-regexp (rx (group (+ digit))) (point-at-eol) t))
+      (setq erc-dcc-byte-count (string-to-number (match-string 0))))
+    ;; FIXME factor this out (see other GET sentinel)
+    (let ((done (= erc-dcc-byte-count (plist-get erc-dcc-entry-data :size))))
+      (erc-display-message
+       nil (if done 'notice '(notice error)) erc-server-process
+       (if done 'dcc-get-complete 'dcc-get-failed)
+       ?v (plist-get erc-dcc-entry-data :size)
+       ?f erc-dcc-file-name
+       ?s (number-to-string erc-dcc-byte-count)
+       ?t (format "%.0f"
+                  (erc-time-diff (plist-get erc-dcc-entry-data :start-time)
+                                 nil))))
+    (kill-buffer)))
+
+(defun erc-dcc--get-file-subprocess (entry file parent-proc)
+  (let* ((buf (generate-new-buffer (file-name-nondirectory file)))
+         (exe (concat invocation-directory invocation-name))
+         (prog `(with-current-buffer (messages-buffer)
+                  (setq erc-dcc-verbose t) ;global
+                  (advice-add 'erc-display-message :override
+                              #'erc-dcc--get-display-messages)
+                  (let ((e ',entry)
+                        p)
+                    (erc-dcc--get-file e ,file nil)
+                    (setq p (plist-get e :peer))
+                    (set-process-query-on-exit-flag p nil)
+                    (message "Starting: %S" (list :entry e :file ,file))
+                    (while (accept-process-output p)))))
+         (proc (start-process file buf exe "-Q" "--batch" "-l" "erc-dcc"
+                              "--eval" (prin1-to-string prog))))
+    (with-current-buffer buf
+      (setq erc-dcc-file-name (plist-get entry :file)
+            erc-dcc-byte-count 0)
+      (set-process-sentinel proc #'erc-dcc--get-file-subprocess-sentinel)
+      (setq erc-server-process parent-proc
+            entry (plist-put entry :peer proc)
+            entry (plist-put entry :start-time (erc-current-time))
+            erc-dcc-entry-data entry))))
+
+(defun erc-dcc-get-file (entry file parent-proc)
+  "Set up a transfer from the remote client to the local over a TCP connection.
+This involves setting up a process filter and a process sentinel,
+and making the connection."
+  (if erc-dcc-get-use-subprocess
+      (erc-dcc--get-file-subprocess (plist-put entry :parent nil)
+                                    file parent-proc)
+    (erc-dcc--get-file entry file parent-proc)))
+
 (defun erc-dcc-append-contents (buffer _file)
   "Append the contents of BUFFER to FILE.
 The contents of the BUFFER will then be erased."
-- 
2.35.1