+create_gpg_home() {
+ # gpg needs (in different versions more or less) files to function correctly,
+ # so we give it its own homedir and generate some valid content for it later on
+ if [ -n "$TMPDIR" ]; then
+ # tmpdir is a directory and current user has rwx access to it
+ # same tests as in apt-pkg/contrib/fileutl.cc GetTempDir()
+ if [ ! -d "$TMPDIR" ] || [ ! -r "$TMPDIR" ] || [ ! -w "$TMPDIR" ] || [ ! -x "$TMPDIR" ]; then
+ unset TMPDIR
+ fi
+ fi
+ GPGHOMEDIR="$(mktemp -d)"
+ CURRENTTRAP="${CURRENTTRAP} cleanup_gpg_home;"
+ trap "${CURRENTTRAP}" 0 HUP INT QUIT ILL ABRT FPE SEGV PIPE TERM
+ if [ -z "$GPGHOMEDIR" ]; then
+ echo "ERROR: Could not create temporary gpg home directory in apt-key ($TMPDIR)"
+ exit 28
+ fi
+ chmod 700 "$GPGHOMEDIR"
+}
+
+prepare_gpg_home() {
+ # crude detection if we are called from a maintainerscript where the
+ # package depends on gnupg or not. We accept recommends here as
+ # well as the script hopefully uses apt-key optionally then like e.g.
+ # debian-archive-keyring for (upgrade) cleanup did
+ if [ -n "$DPKG_MAINTSCRIPT_PACKAGE" ] && [ -z "$APT_KEY_DONT_WARN_ON_DANGEROUS_USAGE" ]; then
+ if ! dpkg-query --show --showformat '${Pre-Depends}${Depends}${Recommends}\n' "$DPKG_MAINTSCRIPT_PACKAGE" 2>/dev/null | grep -q gnupg; then
+ cat >&2 <<EOF
+Warning: The $DPKG_MAINTSCRIPT_NAME maintainerscript of the package $DPKG_MAINTSCRIPT_PACKAGE
+Warning: seems to use apt-key (provided by apt) without depending on gnupg or gnupg2.
+Warning: This will BREAK in the future and should be fixed by the package maintainer(s).
+Note: Check first if apt-key functionality is needed at all - it probably isn't!
+EOF
+ fi
+ fi
+ eval "$(apt-config shell GPG_EXE Apt::Key::gpgcommand)"
+ if [ -n "$GPG_EXE" ] && command_available "$GPG_EXE"; then