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#!/bin/sh |
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|
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|
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vo_sw_dir=${HOME}/vosw |
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|
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error() { |
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echo $@ |
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exit 1 |
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} |
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|
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log() { |
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echo LOG: $@ |
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} |
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|
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get_write_lock() { |
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log "Checking if the vo software area is writable." |
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if [ -z $vo_sw_dir ] ; then |
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error "\$$vo_sw_dir_var not set." |
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fi |
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|
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if [ ! -w $vo_sw_dir ] ; then |
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error "\$$vo_sw_dir_var ($vo_sw_dir) is not writable. (Check your proxy: are you the VO software manager?)" |
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fi |
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log "$vo_sw_dir writable OK." |
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# now do the lockfile shuffle |
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lockfile=$vo_sw_dir/pkgsrc-lock |
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log "checking lockfile $lockfile" |
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if [ -f $lockfile ]; then |
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log "lockfile exists." |
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ls -l $lockfile |
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if [ -z `find $lockfile -mmin -30` ]; then |
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log "stale lockfile ($lockfile is older than 30 minutes)" |
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rm -f $lockfile || error "could not remove $lockfile. Call help." |
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else |
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log "lockfile is still fresh." |
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return 1 |
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fi |
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else |
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log "no lockfile found. Setting lock" |
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fi |
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# At this point, we've concluded we should try and set the lockfile. |
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# be careful to avoid race conditions (although rare). |
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log "attempting to get lock." |
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a=`mktemp $vo_sw_dir/pkgsrc-lock.XXXXXXXXXX` || error "mktemp failed" |
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ln $a $lockfile |
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if [ $? -ne 0 ]; then |
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log "failed to obtain lock" |
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rm $a |
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return 1 |
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fi |
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log "lock set" |
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rm $a |
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unset a |
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trap "rm -f $lockfile" INT TERM EXIT |
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return 0 |
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} |
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|
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echo "try 1:" |
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get_write_lock |
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if [ $? -ne 0 ]; then |
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echo fail |
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else |
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echo ok |
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fi |
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|
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echo "try 2:" |
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get_write_lock |
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if [ $? -ne 0 ]; then |
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echo fail |
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else |
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echo ok |
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fi |
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