47 lines
907 B
Bash
Executable File
47 lines
907 B
Bash
Executable File
#!/bin/sh
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## live-build(7) - System Build Scripts
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## Copyright (C) 2016-2020 The Debian Live team
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## Copyright (C) 2006-2015 Daniel Baumann <mail@daniel-baumann.ch>
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##
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## This program comes with ABSOLUTELY NO WARRANTY; for details see COPYING.
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## This is free software, and you are welcome to redistribute it
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## under certain conditions; see COPYING for details.
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Acquire_lockfile ()
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{
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local FILE="${1:-.lock}"
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Check_lockfile "${FILE}"
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Create_lockfile "${FILE}"
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}
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Check_lockfile ()
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{
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local FILE="${1}"
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if [ -f "${FILE}" ]; then
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Echo_error "${PROGRAM} already locked"
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exit 1
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fi
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}
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Create_lockfile ()
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{
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local FILE="${1}"
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# Create lock trap
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# This automatically removes the lock file in certain conditions
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trap 'ret=${?}; '"rm -f \"${FILE}\";"' exit ${ret}' EXIT HUP INT QUIT TERM
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# Creating lock file
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touch "${FILE}"
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}
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Remove_lockfile ()
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{
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local FILE="${1:-.lock}"
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rm -f "${FILE}"
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}
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