Modern mt-st-git variant for Archlinux

PKGBUILD.mt-st-git.1.14

# Maintainer:  Chris Severance aur.severach aATt spamgourmet dott com
# Contributor: Sam Stuewe <halosghost at archlinux dot info>
# Contributor: skottish <skottish97215 at gmail com>

set -u
_pkgname='mt-st'
pkgname="${_pkgname}-git"
pkgver=1.4.r10.gfbfd923
pkgrel=1
pkgdesc='Utilities for managing magnetic tape storage devices'
arch=('i686' 'x86_64')
url="https://github.com/iustin/${_pkgname}"
license=('GPLv2')
depends=('tar')
makedepends=('git')
provides=("${_pkgname}=${pkgver%.r*}")
conflicts=("${_pkgname}")
source=("${_pkgname}::${url//https/git}.git")
sha256sums=('SKIP')

pkgver() {
  set -u
  cd "${_pkgname}"
  #printf '%s.r%s.g%s' "$(sed -ne 's:^#define VERSION "\(.*\)"$:\1:p' "mt.c")" "$(git rev-list --count HEAD)" "$(git describe --always )" # '
  git describe --long | sed 's/\([^-]*-g\)/r\1/;s/-/./g;s/v//g'
  set +u
}

_cp() {
  mkdir -p "$(dirname $2)"
  cp -a "$1" "$2"
}


prepare() {
  set -u
  cd "${_pkgname}"
  sed -e 's:^#include <sys/types.h>$:#include <sys/sysmacros.h>\n&:g' -i 'mt.c'
  sed -e 's:^SBINDIR=\ \$(DESTDIR)\/\$(EXEC_PREFIX)\/sbin$:SBINDIR=\ \$(DESTDIR)\/\$(EXEC_PREFIX)\/bin:g' -i Makefile
  set +u
}

build() {
  set -u
  cd "${_pkgname}"
  make
  set +u
}

package() {
  set -u
  cd "${_pkgname}"
  DEFTAPE="/dev/nst0" EXEC_PREFIX="/usr" DESTDIR="${pkgdir}" make install
  _cp ../../stinit.service ${pkgdir}/usr/lib/systemd/system/stinit.service
  _cp ../../stinit.def ${pkgdir}/etc/stinit.def
  set +u
}
set +u

# vim:set ts=2 sw=2 et:

stinit.def

# HP Ultrium 6-SCSI
manufacturer=HP model= "Ultrium 6-SCSI" {
        scsi2logical=1
        can-bsr=1
        auto-lock=0
        two-fms=0
        drive-buffering=1
        buffer-writes
        read-ahead=1
        async-writes=1
        can-partitions=0
        fast-eom=1
        mode1 blocksize=0 density=0x58 compression=1
        mode2 compression=1
        mode3 compression=1
        mode4 compression=1
}

stinit.service

[Unit]
Description=Initialize SCSI Tape Drives
[Service]
Type=oneshot
RemainAfterExit=yes
ExecStart=/sbin/stinit -f /etc/stinit.def
[Install]
WantedBy=multi-user.target

You could use install -D instead of the _cp function you wrote.