On 19/03/2024 10:54, deb...@perkelt.hu wrote:
I looked into this and found that
pinky tries to canonicalize the information in the "Where" column
automaticaly, and it has no option to disable this behaviour.
see line 285 pinky.c:
if (*ut_host)
/* See if we can canonicalize it. */
host = canon_host (ut_host);
this results in many unnecessary dns queries.
For example on a debian system with acpi-support, /etc/acpi/lid.sh will
make many requests to find the host $WAYLAND_DISPLAY every time the lid
is opened.
"who" has the --lookup (attempt to canonicalize hostnames via DNS)
option, and doesn't do it by default.
Maybe it would be more lightweight to forget about canonicalization
altogether.
pinky is slow here on Fedora 39 too.
I agree that it should avoid this by default.
pinky is supposed to be a lightweight finger after all.
I'll apply the attached to upstream coreutils soon.
thanks,
Pádraig
From 6d0367c00e0998bf5b5a25358c1f1854555cd03e Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?P=C3=A1draig=20Brady?= <p...@draigbrady.com>
Date: Tue, 19 Mar 2024 13:19:16 +0000
Subject: [PATCH] pinky: disable location canonicalization by default
Behave like who(1) in requiring --lookup to enable this
often slow feature. pinky(1) is supposed to be lightweight after all.
* doc/coreutils.texi (who invocation): Adjust the description to no
longer reference dialup, and be more general about the still significant
delays.
(pinky invocation): Reference the same --lookup description.
* src/pinky.c (main): Accept --lookup to enable DNS lookups.
* NEWS: Mention the change in behavior.
Fixes https://bugs.debian.org/628815
---
NEWS | 3 +++
doc/coreutils.texi | 10 +++++++---
src/pinky.c | 19 ++++++++++++++++++-
3 files changed, 28 insertions(+), 4 deletions(-)
diff --git a/NEWS b/NEWS
index 3a7e2aa57..0f4503cbb 100644
--- a/NEWS
+++ b/NEWS
@@ -65,6 +65,9 @@ GNU coreutils NEWS -*- outline -*-
numfmt will accept lowercase 'k' to indicate Kilo or Kibi units on input,
and uses lowercase 'k' when outputting such units in '--to=si' mode.
+ pinky no longer tries to canonicalize the user's login location by default,
+ rather requiring the new --lookup option to enable this often slow feature.
+
wc no longer ignores encoding errors when counting words.
Instead, it treats them as non white space.
diff --git a/doc/coreutils.texi b/doc/coreutils.texi
index 92c9ceefb..41b644ecf 100644
--- a/doc/coreutils.texi
+++ b/doc/coreutils.texi
@@ -16238,11 +16238,13 @@ Print a line of column headings.
List only the entries that correspond to processes via which the
system is waiting for a user to login. The user name is always @samp{LOGIN}.
+@macro lookupOption
@item --lookup
@opindex --lookup
-Attempt to canonicalize hostnames found in utmp through a DNS lookup. This
-is not the default because it can cause significant delays on systems with
-automatic dial-up internet access.
+Attempt to canonicalize hostnames found in utmp through a DNS lookup.
+This is not the default because of potential delays.
+@end macro
+@lookupOption
@item -m
@opindex -m
@@ -16370,6 +16372,8 @@ format.
Omit the user's full name, remote host, and idle time when printing in
short format.
+@lookupOption
+
@end table
@exitstatus
diff --git a/src/pinky.c b/src/pinky.c
index 0843efd55..77c1c2c01 100644
--- a/src/pinky.c
+++ b/src/pinky.c
@@ -61,6 +61,9 @@ static bool include_home_and_shell = true;
/* if true, use the "short" output format. */
static bool do_short_format = true;
+/* If true, attempt to canonicalize hostnames via a DNS lookup. */
+static bool do_lookup;
+
/* if true, display the ut_host field. */
#if HAVE_STRUCT_XTMP_UT_HOST
static bool include_where = true;
@@ -71,8 +74,15 @@ static bool include_where = true;
static char const *time_format;
static int time_format_width;
+/* for long options with no corresponding short option, use enum */
+enum
+{
+ LOOKUP_OPTION = CHAR_MAX + 1
+};
+
static struct option const longopts[] =
{
+ {"lookup", no_argument, nullptr, LOOKUP_OPTION},
{GETOPT_HELP_OPTION_DECL},
{GETOPT_VERSION_OPTION_DECL},
{nullptr, 0, nullptr, 0}
@@ -279,7 +289,7 @@ print_entry (struct gl_utmp const *utmp_ent)
if (display)
*display++ = '\0';
- if (*ut_host)
+ if (*ut_host && do_lookup)
/* See if we can canonicalize it. */
host = canon_host (ut_host);
if ( ! host)
@@ -499,6 +509,9 @@ usage (int status)
-i omit the user's full name and remote host in short format\n\
-q omit the user's full name, remote host and idle time\n\
in short format\n\
+"), stdout);
+ fputs (_("\
+ --lookup attempt to canonicalize hostnames via DNS\n\
"), stdout);
fputs (HELP_OPTION_DESCRIPTION, stdout);
fputs (VERSION_OPTION_DESCRIPTION, stdout);
@@ -574,6 +587,10 @@ main (int argc, char **argv)
include_home_and_shell = false;
break;
+ case LOOKUP_OPTION:
+ do_lookup = true;
+ break;
+
case_GETOPT_HELP_CHAR;
case_GETOPT_VERSION_CHAR (PROGRAM_NAME, AUTHORS);
--
2.43.0
