Package: emacs;
Reported by: Drew Adams <drew.adams <at> oracle.com>
Date: Sun, 29 Dec 2019 17:06:01 UTC
Severity: wishlist
Tags: patch
Found in version 26.3
Done: Tino Calancha <tino.calancha <at> gmail.com>
Bug is archived. No further changes may be made.
View this message in rfc822 format
From: Tino Calancha <tino.calancha <at> gmail.com> To: Eli Zaretskii <eliz <at> gnu.org> Cc: uyennhi.qm <at> gmail.com, larsi <at> gnus.org, stefankangas <at> gmail.com, 38796 <at> debbugs.gnu.org, monnier <at> iro.umontreal.ca Subject: bug#38796: 26.3; `view-lossage': Use a variable for the lossage limit Date: Fri, 04 Sep 2020 11:31:33 +0200
Eli Zaretskii <eliz <at> gnu.org> writes:
>> FWIW I have been running Emacs almost 3 months using this branch
>> with no issues.
>> If Eli is OK with it, I can merge it to master next week.
>
> Sorry, OK with what? where's the patch which I should agree with?
Branch origin/bug#38796-lossage-limit
The following is the difference with master branch when I updated
the branch (last August 27th):
--8<-----------------------------cut here---------------start------------->8---
diff --git a/doc/emacs/help.texi b/doc/emacs/help.texi
index 06ad5a583d..34a354891b 100644
--- a/doc/emacs/help.texi
+++ b/doc/emacs/help.texi
@@ -573,10 +573,13 @@ Misc Help
@kindex C-h l
@findex view-lossage
+@findex lossage-size
If something surprising happens, and you are not sure what you typed,
use @kbd{C-h l} (@code{view-lossage}). @kbd{C-h l} displays your last
-300 input keystrokes and the commands they invoked. If you see
-commands that you are not familiar with, you can use @kbd{C-h k} or
+input keystrokes and the commands they invoked. By default, Emacs
+stores the last 300 events; if you wish, you can change this number with
+the command @code{lossage-size}.
+If you see commands that you are not familiar with, you can use @kbd{C-h k} or
@kbd{C-h f} to find out what they do.
@kindex C-h e
diff --git a/etc/NEWS b/etc/NEWS
index 964b626d7b..8bb3527d85 100644
--- a/etc/NEWS
+++ b/etc/NEWS
@@ -85,6 +85,10 @@ useful on systems such as FreeBSD which ships only with "etc/termcap".
* Changes in Emacs 28.1
++++
+** The new command 'lossage-limit' controls the maximum number
+of keystrokes and commands recorded.
+
+++
** New variables that hold default buffer names for shell output.
The new constants 'shell-command-buffer-name' and
@@ -92,6 +96,9 @@ The new constants 'shell-command-buffer-name' and
for the output of, respectively, synchronous and async shell
commands.
+** The new command lossage-size' allow users to set the maximum
+number of keystrokes and commands recorded.
+
** Support for '(box . SIZE)' 'cursor-type'.
By default, 'box' cursor always has a filled box shape. But if you
specify 'cursor-type' to be '(box . SIZE)', the cursor becomes a hollow
diff --git a/lisp/comint.el b/lisp/comint.el
index be0e32b9e0..afc8395b36 100644
--- a/lisp/comint.el
+++ b/lisp/comint.el
@@ -2393,7 +2393,7 @@ comint-send-invisible
Then send it to the process running in the current buffer.
The string is sent using `comint-input-sender'.
Security bug: your string can still be temporarily recovered with
-\\[view-lossage]; `clear-this-command-keys' can fix that."
+\\[view-lossage]; `clear-this-command-keys' and `lossage-size' can fix that."
(interactive "P") ; Defeat snooping via C-x ESC ESC
(let ((proc (get-buffer-process (current-buffer)))
(prefix
diff --git a/lisp/edmacro.el b/lisp/edmacro.el
index 71474c0289..52cbf5b5a6 100644
--- a/lisp/edmacro.el
+++ b/lisp/edmacro.el
@@ -35,8 +35,8 @@
;; * `M-x' followed by a command name, to edit a named command
;; whose definition is a keyboard macro.
;;
-;; * `C-h l' (view-lossage), to edit the 300 most recent keystrokes
-;; and install them as the "current" macro.
+;; * `C-h l' (view-lossage), to edit the 300 most recent
+;; keystrokes and install them as the "current" macro.
;;
;; * any key sequence whose definition is a keyboard macro.
;;
diff --git a/lisp/help.el b/lisp/help.el
index 1b0149616f..d3b0e02f08 100644
--- a/lisp/help.el
+++ b/lisp/help.el
@@ -455,9 +455,10 @@ view-external-packages
(info "(efaq)Packages that do not come with Emacs"))
(defun view-lossage ()
- "Display last few input keystrokes and the commands run.
+ "Display last input keystrokes and the commands run.
For convenience this uses the same format as
`edit-last-kbd-macro'.
+See `lossage-size' to update the number of recorded keystrokes.
To record all your input, use `open-dribble-file'."
(interactive)
diff --git a/lisp/term.el b/lisp/term.el
index e77c2c1331..e39d03e8cd 100644
--- a/lisp/term.el
+++ b/lisp/term.el
@@ -2236,7 +2236,8 @@ term-read-noecho
Note that the keystrokes comprising the text can still be recovered
\(temporarily) with \\[view-lossage]. This may be a security bug for some
-applications."
+applications. See `clear-this-command-keys' and `lossage-size' for ways
+to fix that."
(declare (obsolete read-passwd "27.1"))
(let ((ans "")
(c 0)
diff --git a/src/keyboard.c b/src/keyboard.c
index 5fa58abce1..bf8d75b602 100644
--- a/src/keyboard.c
+++ b/src/keyboard.c
@@ -103,15 +103,16 @@ Copyright (C) 1985-1989, 1993-1997, 1999-2020 Free Software Foundation,
/* True in the single-kboard state, false in the any-kboard state. */
static bool single_kboard;
-#define NUM_RECENT_KEYS (300)
-
/* Index for storing next element into recent_keys. */
static int recent_keys_index;
/* Total number of elements stored into recent_keys. */
static int total_keys;
-/* This vector holds the last NUM_RECENT_KEYS keystrokes. */
+/* Size of the recent_keys vector */
+static int lossage_limit = 300;
+
+/* This vector holds the last lossage_limit keystrokes. */
static Lisp_Object recent_keys;
/* Vector holding the key sequence that invoked the current command.
@@ -294,6 +295,7 @@ #define GROW_RAW_KEYBUF \
/* Pointer to next place to store character in kbd_buffer. */
static union buffered_input_event *kbd_store_ptr;
+
/* The above pair of variables forms a "queue empty" flag. When we
enqueue a non-hook event, we increment kbd_store_ptr. When we
dequeue a non-hook event, we increment kbd_fetch_ptr. We say that
@@ -1421,10 +1423,10 @@ command_loop_1 (void)
/* Execute the command. */
{
- total_keys += total_keys < NUM_RECENT_KEYS;
+ total_keys += total_keys < lossage_limit;
ASET (recent_keys, recent_keys_index,
Fcons (Qnil, cmd));
- if (++recent_keys_index >= NUM_RECENT_KEYS)
+ if (++recent_keys_index >= lossage_limit)
recent_keys_index = 0;
}
Vthis_command = cmd;
@@ -3248,15 +3250,15 @@ record_char (Lisp_Object c)
int ix1, ix2, ix3;
if ((ix1 = recent_keys_index - 1) < 0)
- ix1 = NUM_RECENT_KEYS - 1;
+ ix1 = lossage_limit - 1;
ev1 = AREF (recent_keys, ix1);
if ((ix2 = ix1 - 1) < 0)
- ix2 = NUM_RECENT_KEYS - 1;
+ ix2 = lossage_limit - 1;
ev2 = AREF (recent_keys, ix2);
if ((ix3 = ix2 - 1) < 0)
- ix3 = NUM_RECENT_KEYS - 1;
+ ix3 = lossage_limit - 1;
ev3 = AREF (recent_keys, ix3);
if (EQ (XCAR (c), Qhelp_echo))
@@ -3307,12 +3309,12 @@ record_char (Lisp_Object c)
{
if (!recorded)
{
- total_keys += total_keys < NUM_RECENT_KEYS;
+ total_keys += total_keys < lossage_limit;
ASET (recent_keys, recent_keys_index,
/* Copy the event, in case it gets modified by side-effect
by some remapping function (bug#30955). */
CONSP (c) ? Fcopy_sequence (c) : c);
- if (++recent_keys_index >= NUM_RECENT_KEYS)
+ if (++recent_keys_index >= lossage_limit)
recent_keys_index = 0;
}
else if (recorded < 0)
@@ -3326,10 +3328,10 @@ record_char (Lisp_Object c)
while (recorded++ < 0 && total_keys > 0)
{
- if (total_keys < NUM_RECENT_KEYS)
+ if (total_keys < lossage_limit)
total_keys--;
if (--recent_keys_index < 0)
- recent_keys_index = NUM_RECENT_KEYS - 1;
+ recent_keys_index = lossage_limit - 1;
ASET (recent_keys, recent_keys_index, Qnil);
}
}
@@ -10410,6 +10412,62 @@ DEFUN ("input-pending-p", Finput_pending_p, Sinput_pending_p, 0, 1, 0,
? Qt : Qnil);
}
+/* Reallocate recent_keys copying the keystrokes in the right order */
+static void
+update_recent_keys (int new_size, int kept_keys)
+{
+ int osize = ASIZE (recent_keys);
+ eassert (recent_keys_index < osize);
+ eassert (kept_keys <= min (osize, new_size));
+ Lisp_Object v = make_nil_vector (new_size);
+ int i, idx;
+ for (i = 0; i < kept_keys; ++i)
+ {
+ idx = recent_keys_index - kept_keys + i;
+ while (idx < 0)
+ idx += osize;
+ ASET (v, i, AREF (recent_keys, idx));
+ }
+ recent_keys = v;
+ total_keys = kept_keys;
+ recent_keys_index = total_keys % new_size;
+ lossage_limit = new_size;
+
+}
+
+DEFUN ("lossage-size", Flossage_size, Slossage_size, 0, 1,
+ "(list (read-number \"new-size: \" (lossage-size)))",
+ doc: /* Return the maximum number of saved keystrokes.
+Called with ARG, then set this number to ARG.
+
+The saved keystrokes are the records shown by `view-lossage'.
+If you want to disable the lossage records, then set this maximum to a
+small number, e.g. 0.
+usage: (lossage-size &optional ARG) */)
+ (Lisp_Object arg)
+{
+ if (NILP(arg))
+ return make_fixnum(lossage_limit == 1 ? 0 : lossage_limit);
+
+ if (!FIXNATP (arg))
+ user_error ("Value must be a non-negative integer");
+ int osize = ASIZE (recent_keys);
+ eassert (lossage_limit == osize);
+ int new_size = XFIXNAT (arg);
+
+ if (new_size == osize)
+ return Qnil;
+ /* Internally, the minimum lossage_limit is 1; users will likely use
+ 0 to disable the lossage, thus here we change 0 -> 1. */
+ if (new_size == 0)
+ new_size = 1;
+
+ int kept_keys = new_size > osize ? total_keys : min (new_size, total_keys);
+ update_recent_keys (new_size, kept_keys);
+
+ return Qnil;
+}
+
DEFUN ("recent-keys", Frecent_keys, Srecent_keys, 0, 1, 0,
doc: /* Return vector of last few events, not counting those from keyboard macros.
If INCLUDE-CMDS is non-nil, include the commands that were run,
@@ -10419,21 +10477,21 @@ DEFUN ("recent-keys", Frecent_keys, Srecent_keys, 0, 1, 0,
bool cmds = !NILP (include_cmds);
if (!total_keys
- || (cmds && total_keys < NUM_RECENT_KEYS))
+ || (cmds && total_keys < lossage_limit))
return Fvector (total_keys,
XVECTOR (recent_keys)->contents);
else
{
Lisp_Object es = Qnil;
- int i = (total_keys < NUM_RECENT_KEYS
+ int i = (total_keys < lossage_limit
? 0 : recent_keys_index);
- eassert (recent_keys_index < NUM_RECENT_KEYS);
+ eassert (recent_keys_index < lossage_limit);
do
{
Lisp_Object e = AREF (recent_keys, i);
if (cmds || !CONSP (e) || !NILP (XCAR (e)))
es = Fcons (e, es);
- if (++i >= NUM_RECENT_KEYS)
+ if (++i >= lossage_limit)
i = 0;
} while (i != recent_keys_index);
es = Fnreverse (es);
@@ -10531,7 +10589,7 @@ DEFUN ("this-single-command-raw-keys", Fthis_single_command_raw_keys,
DEFUN ("clear-this-command-keys", Fclear_this_command_keys,
Sclear_this_command_keys, 0, 1, 0,
doc: /* Clear out the vector that `this-command-keys' returns.
-Also clear the record of the last 300 input events, unless optional arg
+Also clear the record of the last input events, unless optional arg
KEEP-RECORD is non-nil. */)
(Lisp_Object keep_record)
{
@@ -11686,7 +11744,7 @@ syms_of_keyboard (void)
staticpro (&modifier_symbols);
}
- recent_keys = make_nil_vector (NUM_RECENT_KEYS);
+ recent_keys = make_nil_vector (lossage_limit);
staticpro (&recent_keys);
this_command_keys = make_nil_vector (40);
@@ -11736,6 +11794,7 @@ syms_of_keyboard (void)
defsubr (&Srecursive_edit);
defsubr (&Sinternal_track_mouse);
defsubr (&Sinput_pending_p);
+ defsubr (&Slossage_size);
defsubr (&Srecent_keys);
defsubr (&Sthis_command_keys);
defsubr (&Sthis_command_keys_vector);
diff --git a/test/src/keyboard-tests.el b/test/src/keyboard-tests.el
index 1988ba51a7..d4ac4a518d 100644
--- a/test/src/keyboard-tests.el
+++ b/test/src/keyboard-tests.el
@@ -32,5 +32,23 @@ keyboard-unread-command-events
(read-event nil nil 2))
?\C-b)))
+(ert-deftest keyboard-lossage-size ()
+ "Test `lossage-size'."
+ (dolist (val (list 100 300 400 400 500 1000 700 300))
+ (lossage-size val)
+ (should (= val (lossage-size))))
+ (let ((current-size (lossage-size)))
+ ;; Set lossage size to 1 and 0 are equivalent
+ (lossage-size 0)
+ (should (zerop (lossage-size)))
+ (lossage-size 1)
+ (should (zerop (lossage-size)))
+ (lossage-size current-size)
+ ;; Argument must be a natural number
+ (should-error (lossage-size -5))
+ (should-error (lossage-size "200"))
+ (should (= (lossage-size) current-size))))
+
+
(provide 'keyboard-tests)
;;; keyboard-tests.el ends here
--8<-----------------------------cut here---------------end--------------->8---
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1994-97 Ian Jackson.