зеркало из https://github.com/github/ruby.git
58 строки
989 B
Bash
Executable File
58 строки
989 B
Bash
Executable File
#!/bin/sh
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# usage: ifchange target temporary
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set -e
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timestamp=
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keepsuffix=
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until [ "$0" = 0 ]; do
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case "$1" in
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--timestamp)
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timestamp=.
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;;
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--timestamp=*)
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timestamp=`expr \( "$1" : '[^=]*=\(.*\)' \)`
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;;
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--keep)
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keepsuffix=.old
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;;
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--keep=*)
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keepsuffix=`expr \( "$1" : '[^=]*=\(.*\)' \)`
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;;
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*)
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break
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;;
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esac
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shift
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done
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target="$1"
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temp="$2"
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if [ "$temp" = - ]; then
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temp="tmpdata$$.tmp~"
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cat > "$temp" || exit $?
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trap 'rm -f "$temp"' 0
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fi
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if cmp "$target" "$temp" >/dev/null 2>&1; then
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echo "$target unchanged"
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rm -f "$temp"
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else
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echo "$target updated"
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[ x"${keepsuffix}" = x ] || mv -f "$target" "${target}${keepsuffix}"
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mv -f "$temp" "$target"
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fi
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if [ -n "${timestamp}" ]; then
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if [ x"${timestamp}" = x. ]; then
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case "$target" in
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*/*)
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timestamp=`dirname "$target"`/.time.`basename "$target"`
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;;
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*)
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timestamp=.time."$target"
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;;
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esac
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fi
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: > "$timestamp"
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fi
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