From 103dff282db44ea6b492c5b175b81688fb5e09c9 Mon Sep 17 00:00:00 2001
From: arehbein <arehbein@sysmocom.de>
Date: Sun, 13 Nov 2022 14:24:30 +0100
Subject: [PATCH] WIP: dumpcap-start/stop: Make script fail, not hang on sudo
 prompt

 - Also: Fix output of '-e' option in pure POSIX shell

Change-Id: Id160384bf624a4eb0f419cb8ba07d8b69bb693f3
---
 ttcn3-dumpcap-start.sh | 16 ++++++++++++++--
 ttcn3-dumpcap-stop.sh  | 21 ++++++++++-----------
 2 files changed, 24 insertions(+), 13 deletions(-)

diff --git a/ttcn3-dumpcap-start.sh b/ttcn3-dumpcap-start.sh
index eb390fddb..c4ead8c31 100755
--- a/ttcn3-dumpcap-start.sh
+++ b/ttcn3-dumpcap-start.sh
@@ -13,9 +13,21 @@ GSMTAP_PORT=4729
 
 TESTCASE=$1
 
+if ! [ "$(id -u)" = "0" ]; then
+	SUDOSTR="sudo -n"
+	# Check if sudo /usr/bin/kill, sudo /usr/bin/tcpdump can always be run without password prompt (otherwise this script may hang)
+	sudo -k
+	if ! (sudo -n echo test >/dev/null 2>&1); then
+		echo "Error: Make sure 'sudo /usr/bin/kill' and 'sudo /usr/bin/tcpdump' can be executed without a password (NOPASSWD in sudoers file)" >&2
+		exit 1
+	fi
+else
+	SUDOSTR=""
+fi
+
 kill_rm_pidfile() {
-	if [ -e $1 ]; then
-		kill "$(cat "$1")"
+	if ! [ -e "$1" ] && [ -s "$1" ]; then
+		$SUDOSTR kill "$(cat "$1")" 2>&1 || grep -v "No such process"
 		rm $1
 	fi
 }
diff --git a/ttcn3-dumpcap-stop.sh b/ttcn3-dumpcap-stop.sh
index e13fbc0f4..64f261a3a 100755
--- a/ttcn3-dumpcap-stop.sh
+++ b/ttcn3-dumpcap-stop.sh
@@ -5,18 +5,17 @@ PIDFILE_NETCAT=/tmp/netcat.pid
 TESTCASE=$1
 VERDICT="$2"
 
-kill_rm_pidfile() {
-if [ -e $1 ]; then
-        PSNAME="$(ps -q "$(cat "$1")" -o comm=)"
-	if [ "$PSNAME" != "sudo" ]; then
-		kill "$(cat "$1")"
-	else
-	# NOTE: This requires you to be root or something like
-	# "laforge ALL=NOPASSWD: /usr/sbin/tcpdump, /bin/kill" in your sudoers file
-		sudo kill "$(cat "$1")"
-	fi
-	rm $1
+if ! [ "$(id -u)" = "0" ]; then
+	SUDOSTR="sudo -n"
+else
+	SUDOSTR=""
 fi
+
+kill_rm_pidfile() {
+	if ! [ -e "$1" ] && [ -s "$1" ]; then
+		$SUDOSTR kill "$(cat "$1")" 2>&1 || grep -v "No such process"
+		rm $1
+	fi
 }
 
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