From dcceb7b83c10cb09e91aa1fd1763e0bd820b15f1 Mon Sep 17 00:00:00 2001
From: Mike Fleetwood <mike.fleetwood@googlemail.com>
Date: Sat, 29 Feb 2020 15:53:23 +0000
Subject: [PATCH] Reliably detect running gpartedbin using pidof (!54)

Debian user reported a bug [1] that when they had PS_FORMAT environment
variable set it prevented GParted running:

    # export PS_FORMAT='ruser,uid,pid,ppid,pri,ni,%cpu,%mem,vsz,rss,stat,tty,start,time,command'
    # gparted
    The process gpartedbin is already running.
    Only one gpartedbin process is permitted.
    # echo $?
    1

Using ps column 'command' includes the command and all it's arguments,
rather than just the command name as ps displays by default.  Thus the
shell wrapper finds the grep command it's using when searching for the
gpartedbin executable.

    # ps -e | grep gpartedbin
    root         0 26114 14777  19   0  0.0  0.0 112712   940 S+   pts/0    10:42:02 00:00:00 grep --color=auto gpartedbin

Fix by searching for running processes using pidof.  pgrep does regular
expression matching where as pidof checks program name is the same [2].
Therefore use of pidof is preferred over pgrep [3].

[1] Debian bug #864932 - gparted fails if PS_FORMAT options are
                         specified
    https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=864932

[2] Difference between pidof and pgrep?
    https://stackoverflow.com/questions/52151698/difference-between-pidof-and-pgrep

[3] [PATCH] gparted.in: Use reliable way of detecting gpartedbin process
    existence
    https://git.alpinelinux.org/aports/tree/community/gparted/gparted.in-Use-reliable-way-of-detecting-gpartedbin-.patch

Closes !54 - Fix gparted not launching when PS_FORMAT environment
             variable set
---
 gparted.in | 10 +++++-----
 1 file changed, 5 insertions(+), 5 deletions(-)

diff --git a/gparted.in b/gparted.in
index 3f9b0f1a..e021eb25 100755
--- a/gparted.in
+++ b/gparted.in
@@ -30,7 +30,7 @@
 #
 #  Only permit one instance of GParted to execute at a time
 #
-if test "z`ps -e | grep gpartedbin`" != "z"; then
+if pidof gpartedbin 1> /dev/null; then
 	echo "The process gpartedbin is already running."
 	echo "Only one gpartedbin process is permitted."
 	exit 1
@@ -94,7 +94,7 @@ fi
 HAVE_SYSTEMCTL=no
 for k in '' `echo "$PATH" | sed 's,:, ,g'`; do
 	if test -x "$k/systemctl"; then
-		if test "z`ps -e | grep systemd`" != "z"; then
+		if pidof systemd 1> /dev/null; then
 			HAVE_SYSTEMCTL=yes
 			break
 		fi
@@ -107,7 +107,7 @@ done
 #
 HAVE_UDISKS2_INHIBIT=no
 if test -x "/usr/lib/udisks2/udisks2-inhibit"; then
-	if test "z`ps -e | grep 'udisksd'`" != "z"; then
+	if pidof udisksd 1> /dev/null; then
 		HAVE_UDISKS2_INHIBIT=yes
 	fi
 fi
@@ -119,7 +119,7 @@ fi
 HAVE_UDISKS=no
 for k in '' `echo "$PATH" | sed 's,:, ,g'`; do
 	if test -x "$k/udisks"; then
-		if test "z`ps -e | grep udisks-daemon`" != "z"; then
+		if pidof udisks-daemon 1> /dev/null; then
 			HAVE_UDISKS=yes
 			break
 		fi
@@ -133,7 +133,7 @@ done
 HAVE_HAL_LOCK=no
 for k in '' `echo "$PATH" | sed 's,:, ,g'`; do
 	if test -x "$k/hal-lock"; then
-		if test "z`ps -e | grep hald`" != "z"; then
+		if pidof hald 1> /dev/null; then
 			HAVE_HAL_LOCK=yes
 			break
 		fi