jjb/shell/common/common/sh/tempdir.sh

#!/bin/bash
## -----------------------------------------------------------------------
## Intent: Automatic setup/teardown a scratch area for testing.
## -----------------------------------------------------------------------
## Usage:
##   o source common/common.sh --common-args-begin-- --tempdir
##   o source common/common/sh/tempdir.sh
## -----------------------------------------------------------------------
## Note:
##   o Argument --preserve can be used to inhibit tempdir removal
##     and test file cleanup at script exit.
## -----------------------------------------------------------------------

# __DEBUG_COMMON__=1
[[ -v __DEBUG_COMMON__ ]] && echo "${BASH_SOURCE[0]}: BEGIN"

##-------------------##
##---]  GLOBALS  [---##
##-------------------##
if [[ ! -v __COMMON_TEMP_DIRS__ ]]; then
    declare -g -a __COMMON_TEMP_DIRS__
fi

## -----------------------------------------------------------------------
## Intent: Allocate a transient tmpdir
## -----------------------------------------------------------------------
## NOTE:
##   o Caller should export TMPDIR="${path}"
##   o TMPDIR= only visible when sourced form top level parent scope
## -----------------------------------------------------------------------
function common_tempdir_mkdir()
{
    local var="$1"; shift

    local pkgbase="${0##*/}" # basename
    local pkgname="${pkgbase%.*}"

    local __junk__
    local __junk__="$(mktemp -d -t "${pkgname}.XXXXXXXXXX")"

    __COMMON_TEMP_DIRS__+=("$__junk__")

    export TMPDIR="$__junk__"
    eval "${var}=${__junk__}"# replace with typeset

    # declare -p __COMMON_TEMP_DIRS__
    return
}

## -----------------------------------------------------------------------
## Intent: Preserve allocated temp directories on exit
## -----------------------------------------------------------------------
## Usage:
##   o kill -s 'SIGSYS' $$
## -----------------------------------------------------------------------
function sigtrap_preserve()
{
    local dir
    for dir in "${__COMMON_TEMP_DIRS__[@]}";
    do
	    touch "$dir/.preserve"
    done
}
trap sigtrap_preserve SIGSYS

## -----------------------------------------------------------------------
## Intent: Tempdir cleanup on exit
## -----------------------------------------------------------------------
function sigtrap()
{
    local dir
    # declare -p __COMMON_TEMP_DIRS__
    for dir in "${__COMMON_TEMP_DIRS__[@]}";
    do
	if [ -e "$dir/.preserve" ]; then
	    echo "Preserving test output: $TMPDIR"
	    find "$TMPDIR" -ls
	else
	    /bin/rm -fr "$TMPDIR"
	fi
    done
    return
}
trap sigtrap EXIT

[[ -v __DEBUG_COMMON__ ]] && echo "${BASH_SOURCE[0]}: END"
unset __DEBUG_COMMON__

: # NOP

# [EOF]