bash: Fix shellcheck warnings

Signed-off-by: a1346054 <36859588+a1346054@users.noreply.github.com>

autogen.sh

@@ -1,10 +1,10 @@
 #!/bin/sh
 
-test -n "$srcdir" || srcdir=`dirname "$0"`
+test -n "$srcdir" || srcdir=$(dirname "$0")
 test -n "$srcdir" || srcdir=.
 
-olddir=`pwd`
-cd $srcdir
+olddir=$(pwd)
+cd "$srcdir"
 
 if ! (autoreconf --version >/dev/null 2>&1); then
         echo "*** No autoreconf found, please install it ***"
@@ -15,5 +15,5 @@ mkdir -p m4
 
 autoreconf --force --install --verbose
 
-cd $olddir
+cd "$olddir"
 test -n "$NOCONFIGURE" || "$srcdir/configure" "$@"

ci/builddeps.sh

@@ -5,7 +5,7 @@
 set -eux
 set -o pipefail
 
-usage () {
+usage() {
     if [ "${1-2}" -ne 0 ]; then
         exec >&2
     fi

tests/libtest.sh

@@ -42,11 +42,11 @@ PATH="$PATH:/usr/sbin:/sbin"
 
 tempdir=$(mktemp -d /var/tmp/tap-test.XXXXXX)
 touch "${tempdir}/.testtmp"
-function cleanup () {
+cleanup() {
     if test -n "${TEST_SKIP_CLEANUP:-}"; then
         echo "Skipping cleanup of ${tempdir}"
     elif test -f "${tempdir}/.testtmp"; then
-        rm "${tempdir}" -rf
+        rm -rf "${tempdir}"
     fi
 }
 trap cleanup EXIT

tests/test-run.sh

@@ -17,7 +17,7 @@ echo "ok - Help works"
 
 for ALT in "" "--unshare-user-try" "--unshare-pid" "--unshare-user-try --unshare-pid"; do
     # Test fuse fs as bind source
-    if [ x$FUSE_DIR != x ]; then
+    if [ "x$FUSE_DIR" != "x" ]; then
         $RUN $ALT --proc /proc --dev /dev --bind $FUSE_DIR /tmp/foo true
         echo "ok - can bind-mount a FUSE directory with $ALT"
     else
@@ -44,9 +44,9 @@ for ALT in "" "--unshare-user-try"  "--unshare-pid" "--unshare-user-try --unshar
     fi
     echo "ok - cannot read /etc/shadow with $ALT"
     # Unreadable dir
-    if [ x$UNREADABLE != x ]; then
+    if [ "x$UNREADABLE" != "x" ]; then
         echo -n "expect EPERM: " >&2
-        if $RUN $ALT --unshare-net --proc /proc --dev /dev --bind $UNREADABLE  /tmp/foo cat /tmp/foo ; then
+        if $RUN $ALT --unshare-net --proc /proc --dev /dev --bind $UNREADABLE /tmp/foo cat /tmp/foo; then
             assert_not_reached Could read $UNREADABLE
         fi
         echo "ok - cannot read $UNREADABLE with $ALT"