usage () {
cat <<END
usage:
- expire-iso8601 [<options>] <unit-in-seconds> <slop-in-seconds>
- <min-interval-in-units> <number-to-keep>
- [<min-interval-in-units> <number-to-keep> ...]
+ expire-iso8601 [<options>] <number>x<interval> [<number>x<interval> ...]
options:
- -n do not really delete
- -r recursive removal (rm -r)
+ -u<unitlen> <interval> is measured in units of <unitlen> seconds
+ (default is 86400, so <interval> is in days)
+ -s<slop> allow kept items to be <slop> seconds shorter apart than
+ specified; default is 10% of <unitlen>
+ -n do not really delete
+ -r recursive removal (rm -r)
example:
- /home/ian/junk/expire-iso8601 86400 10000 1 14 7 4
- uses units of 86400s (1 day) with a slop of 10ks;
+ /home/ian/junk/expire-iso8601 14x1 4x7
+ uses units of 86400s (1 day) with a slop of 8640
it keeps 14 daily items
- (that is 14 items, dated no less than 86400-10000s apart)
- and 7 weekly items
- (that is 7 items, dated no less than 7*86400-10000s apart)
+ (that is 14 items, dated no less than 86400-8640 apart)
+ and 4 weekly items
+ (that is 4 items, dated no less than 7*86400-8640 apart)
the 14 daily and 7 weekly items may be the same, or not
- There is no need to sort the list of interval/number pairs.
+ There is no need to sort the list of <number>x<interval> pairs.
exit status:
0 ok
4 rm failed
END
}
+# Copyright 2006 Ian Jackson <ian@chiark.greenend.org.uk>
+#
+# This script and its documentation (if any) are free software; you
+# can redistribute it and/or modify them under the terms of the GNU
+# General Public License as published by the Free Software Foundation;
+# either version 3, or (at your option) any later version.
+#
+# chiark-named-conf and its manpage are distributed in the hope that
+# it will be useful, but WITHOUT ANY WARRANTY; without even the
+# implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR
+# PURPOSE. See the GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License along
+# with this program; if not, consult the Free Software Foundation's
+# website at www.fsf.org, or the GNU Project website at www.gnu.org.
+
+
trap 'exit 16' 0
badusage () { echo >&2 "bad usage: $*"; usage >&2; trap '' 0; exit 8; }
#-------------------- argument parsing --------------------
+alldigits () {
+ [ "x${2##*[^0-9]}" = "x$2" ] || \
+ badusage "bad $1 \`$2'; must be all digits"
+ [ "$2" ] || badusage "bad $2; must be nonempty"
+ eval $1='$2'
+}
+
rm=rm
+recurse=''
+unit=86400
+slop=''
+
while [ $# -ge 1 ]; do
arg=$1; shift
case "$arg" in
--help) usage; exit 0 ;;
--*) badusage "unknown option $arg" ;;
-*)
+ val=${arg#-?}
case "$arg" in
-n*) rm=: ;;
-r*) recurse=-r ;;
+ -u*) alldigits unit "$val"; arg='' ;;
+ -s*) alldigits slop "$val"; arg='' ;;
*) badusage "unknown option ${1:0:2}" ;;
esac
arg=-${arg#-?}
esac
done
-[ $# -ge 4 ] || badusage 'too few arguments'
-
-unit=$1
-slop=$2
-shift;shift
+[ $# -ge 1 ] || badusage 'too few arguments'
+[ "$slop" ] || slop=$(( $unit / 10 ))
-[ $(($# % 2)) = 0 ] || badusage 'odd keep arguments (need min/extent pairs)'
-argl="$*"
-
-alldigits () {
- [ "x${1##*[^0-9]}" = "x$1" ] || badusage "$2 must be all digits"
- [ x$1 ] || badusage "$2 must be nonempty"
-}
-
-while [ $# -gt 0 ]; do
- min=$1; shift; extent=$1; shift
- alldigits $min min
- alldigits $extent extent
+for ni in "$@"; do
+ case "$ni" in *x*);; *) badusage "bad <number>x<interval> $ni";; esac
+ alldigits number "${ni%%x*}"
+ alldigits interval "${ni#*x}"
done
#-------------------- scanning the directory ----------
# We process each minimum/extent pair, to have it select a bunch of
# versions to keep. We annotate entries in $l: if we are keeping
-# an entry we prepend a colon.
+# an entry we prepend a colon; temporarily, if we are keeping an entry
+# because of this particular minimum/extent, we prepend a comma.
# For each minimum/extent pair we look at the list from most recent
# to least recent,
END
)
-set $argl
-while [ $# != 0 ]; do
- min=$(( $1 * $unit - $slop ))
- wantcount=$2
+for ni in "$@"; do
+ wantcount=${ni%x*}
+
+ div=1
+
+ while true; do
+ min=$(( (${ni#*x} * $unit) / $div - $slop ))
+
+ ls=''
+ lnew=''
+ skipped=0
+ for ce in $l; do
+ cn=${ce#*/}; cl=${ce%%/*}
+ cs=${cl#,}; cs=${cs#:}
+ case $cl in ,*) ls=$cs; continue;; esac
+ if [ $wantcount != 0 ]; then
+ if ! [ "$ls" ] || \
+ [ $(( $ls - $cs )) -ge $min ]; then
+ echo "keep (for $ni) $cn"
+ ce=,$ce
+ ls=$cs
+ wantcount=$(( $wantcount - 1 ))
+ else
+ skipped=$(( $skipped+1 ))
+ fi
+ fi
+ lnew="$lnew $ce"
+ done
+ l=$lnew
+
+ if [ $wantcount = 0 ]; then break; fi
+ printf "%s" "insufficient (for $ni) by $wantcount"
+ if [ $skipped = 0 ]; then echo; break; fi
+ div=$(( $div * 2 ))
+ echo " shortening interval ${div}x"
+ done
- ls=''
+ # s/([,:]+).*/:\1/g
lnew=''
for ce in $l; do
- cn=${ce#*/}; cl=${ce%%/*}; cs=${cl#:}
- if [ $wantcount != 0 ]; then
- if ! [ "$ls" ] || \
- [ $(( $ls - $cs )) -ge $min ]; then
- echo "keep (for $1 $2) $cn"
- ls=$cs
- ce=:$cs/$cn
- wantcount=$(( $wantcount - 1 ))
- fi
- fi
+ case $ce in ,*) ce=:${ce#,};; esac
+ case $ce in ::*) ce=${ce#:};; esac
lnew="$lnew $ce"
done
- if [ $wantcount != 0 ];then
- echo "insufficient (for $1 $2) by $wantcount"
- fi
- shift;shift
l=$lnew
done
*)
cn=${ce#*/}
nonbroken_echo "expire $cn"
- echo $rm $recurse -- $cn &
+ $rm $recurse -- $cn &
jobs="$jobs $!"
;;
esac
~ian / chiark-utils.git / blobdiff