[ViewVC] Annotation of: cvsroot/UserCode/cbrown/Development/DistributedModelCalculations/Utilities/TimeOut

#!/bin/bash
#
# This script is based on a script found here: 
# http://www.bashcookbook.com/bashinfo/source/bash-4.0/examples/scripts/timeout3
#
# The original description is found below
# ##############################################################
#
# The Bash shell script executes a command with a time-out.
# Upon time-out expiration SIGTERM (15) is sent to the process. If the signal
# is blocked, then the subsequent SIGKILL (9) terminates it.
#
# Based on the Bash documentation example.

# Hello Chet,
# please find attached a "little easier"  :-)  to comprehend
# time-out example.  If you find it suitable, feel free to include
# anywhere: the very same logic as in the original examples/scripts, a
# little more transparent implementation to my taste.
#
# Dmitry V Golovashkin <Dmitry.Golovashkin@sas.com>

scriptName="${0##*/}"

declare -i DEFAULT_TIMEOUT=9
declare -i DEFAULT_INTERVAL=1
declare -i DEFAULT_DELAY=1

# Timeout.
declare -i timeout=DEFAULT_TIMEOUT
# Interval between checks if the process is still alive.
declare -i interval=DEFAULT_INTERVAL
# Delay between posting the SIGTERM signal and destroying the process by SIGKILL.
declare -i delay=DEFAULT_DELAY

function printUsage() {
    cat <<EOF

Synopsis
    $scriptName [-t timeout] [-i interval] [-d delay] command
    Execute a command with a time-out.
    Upon time-out expiration SIGTERM (15) is sent to the process. If SIGTERM
    signal is blocked, then the subsequent SIGKILL (9) terminates it.

    -t timeout
        Number of seconds to wait for command completion.
        Default value: $DEFAULT_TIMEOUT seconds.

    -i interval
        Interval between checks if the process is still alive.
        Positive integer, default value: $DEFAULT_INTERVAL seconds.

    -d delay
        Delay between posting the SIGTERM signal and destroying the
        process by SIGKILL. Default value: $DEFAULT_DELAY seconds.

As of today, Bash does not support floating point arithmetic (sleep does),
therefore all delay/time values must be integers.
EOF
}

# Options.
while getopts ":t:i:d:" option; do
    case "$option" in
        t) timeout=$OPTARG ;;
        i) interval=$OPTARG ;;
        d) delay=$OPTARG ;;
        *) printUsage; exit 1 ;;
    esac
done
shift $((OPTIND - 1))

# $# should be at least 1 (the command to execute), however it may be strictly
# greater than 1 if the command itself has options.
if (($# == 0 || interval <= 0)); then
    printUsage
    exit 1
fi
export HAVEKILLED=0
# kill -0 pid   Exit code indicates if a signal may be sent to $pid process.
(
    ((t = timeout))

    while ((t > 0)); do
        sleep $interval
        kill -0 $$ || exit 0
        ((t -= interval))
    done

    # Be nice, post SIGTERM first.
    # The 'exit 0' below will be executed if any preceeding command fails.
    echo "Sorry have to kill the process as it took longer than $timeout seconds (checked after $interval)"
    kill -s SIGTERM $$ && kill -0 $$ || exit 0
    export HAVEKILLED=1
    sleep $delay
    kill -s SIGKILL $$
) 2> /dev/null &

exec "$@"
Revision:	1.1
Committed:	Thu May 17 12:01:33 2012 UTC (12 years, 11 months ago) by buchmann
Branch:	MAIN
Log Message:	added timeout script
#	User	Rev	Content
1	buchmann	1.1	#!/bin/bash
2			#
3			# This script is based on a script found here:
4			# http://www.bashcookbook.com/bashinfo/source/bash-4.0/examples/scripts/timeout3
5			#
6			# The original description is found below
7			# ##############################################################
8			#
9			# The Bash shell script executes a command with a time-out.
10			# Upon time-out expiration SIGTERM (15) is sent to the process. If the signal
11			# is blocked, then the subsequent SIGKILL (9) terminates it.
12			#
13			# Based on the Bash documentation example.
14
15			# Hello Chet,
16			# please find attached a "little easier" :-) to comprehend
17			# time-out example. If you find it suitable, feel free to include
18			# anywhere: the very same logic as in the original examples/scripts, a
19			# little more transparent implementation to my taste.
20			#
21			# Dmitry V Golovashkin <Dmitry.Golovashkin@sas.com>
22
23			scriptName="${0##*/}"
24
25			declare -i DEFAULT_TIMEOUT=9
26			declare -i DEFAULT_INTERVAL=1
27			declare -i DEFAULT_DELAY=1
28
29			# Timeout.
30			declare -i timeout=DEFAULT_TIMEOUT
31			# Interval between checks if the process is still alive.
32			declare -i interval=DEFAULT_INTERVAL
33			# Delay between posting the SIGTERM signal and destroying the process by SIGKILL.
34			declare -i delay=DEFAULT_DELAY
35
36			function printUsage() {
37			cat <<EOF
38
39			Synopsis
40			$scriptName [-t timeout] [-i interval] [-d delay] command
41			Execute a command with a time-out.
42			Upon time-out expiration SIGTERM (15) is sent to the process. If SIGTERM
43			signal is blocked, then the subsequent SIGKILL (9) terminates it.
44
45			-t timeout
46			Number of seconds to wait for command completion.
47			Default value: $DEFAULT_TIMEOUT seconds.
48
49			-i interval
50			Interval between checks if the process is still alive.
51			Positive integer, default value: $DEFAULT_INTERVAL seconds.
52
53			-d delay
54			Delay between posting the SIGTERM signal and destroying the
55			process by SIGKILL. Default value: $DEFAULT_DELAY seconds.
56
57			As of today, Bash does not support floating point arithmetic (sleep does),
58			therefore all delay/time values must be integers.
59			EOF
60			}
61
62			# Options.
63			while getopts ":t:i:d:" option; do
64			case "$option" in
65			t) timeout=$OPTARG ;;
66			i) interval=$OPTARG ;;
67			d) delay=$OPTARG ;;
68			*) printUsage; exit 1 ;;
69			esac
70			done
71			shift $((OPTIND - 1))
72
73			# $# should be at least 1 (the command to execute), however it may be strictly
74			# greater than 1 if the command itself has options.
75			if (($# == 0 \|\| interval <= 0)); then
76			printUsage
77			exit 1
78			fi
79			export HAVEKILLED=0
80			# kill -0 pid Exit code indicates if a signal may be sent to $pid process.
81			(
82			((t = timeout))
83
84			while ((t > 0)); do
85			sleep $interval
86			kill -0 $$ \|\| exit 0
87			((t -= interval))
88			done
89
90			# Be nice, post SIGTERM first.
91			# The 'exit 0' below will be executed if any preceeding command fails.
92			echo "Sorry have to kill the process as it took longer than $timeout seconds (checked after $interval)"
93			kill -s SIGTERM $$ && kill -0 $$ \|\| exit 0
94			export HAVEKILLED=1
95			sleep $delay
96			kill -s SIGKILL $$
97			) 2> /dev/null &
98
99			exec "$@"