Meta: Don't tell to run script as root when that's not the actual error

Before, and that was the cause of many confusion in #build-problems
on Discord, the Meta/build-image-*.sh scripts would error out with
the message "this script needs to run as root" while the actual error
was unrelated.

Meta/build-image-extlinux.sh

@@ -8,7 +8,19 @@ die() {
 }
 
 if [ "$(id -u)" != 0 ]; then
- exec sudo -E -- "$0" "$@" || die "this script needs to run as root"
+ set +e
+ ${SUDO} -E -- sh -c "\"$0\" $* || exit 42"
+ case $? in
+ 1)
+ die "this script needs to run as root"
+ ;;
+ 42)
+ exit 1
+ ;;
+ *)
+ exit 0
+ ;;
+ esac
 else
  : "${SUDO_UID:=0}" "${SUDO_GID:=0}"
 fi

Meta/build-image-grub.sh

@@ -8,7 +8,19 @@ die() {
 }
 
 if [ "$(id -u)" != 0 ]; then
- exec sudo -E -- "$0" "$@" || die "this script needs to run as root"
+ set +e
+ ${SUDO} -E -- sh -c "\"$0\" $* || exit 42"
+ case $? in
+ 1)
+ die "this script needs to run as root"
+ ;;
+ 42)
+ exit 1
+ ;;
+ *)
+ exit 0
+ ;;
+ esac
 else
  : "${SUDO_UID:=0}" "${SUDO_GID:=0}"
 fi

Meta/build-image-limine.sh

@@ -17,7 +17,19 @@ if [ ! -d "limine" ]; then
 fi
 
 if [ "$(id -u)" != 0 ]; then
- exec sudo -E -- "$0" "$@" || die "this script needs to run as root"
+ set +e
+ ${SUDO} -E -- sh -c "\"$0\" $* || exit 42"
+ case $? in
+ 1)
+ die "this script needs to run as root"
+ ;;
+ 42)
+ exit 1
+ ;;
+ *)
+ exit 0
+ ;;
+ esac
 else
  : "${SUDO_UID:=0}" "${SUDO_GID:=0}"
 fi

Meta/build-image-qemu.sh

@@ -31,8 +31,19 @@ if [ "$(id -u)" != 0 ]; then
  if [ -x "$FUSE2FS_PATH" ] && $FUSE2FS_PATH --help 2>&1 |grep fakeroot > /dev/null; then
  USE_FUSE2FS=1
  else
- ${SUDO} -E -- "$0" "$@" || die "this script needs to run as root"
- exit 0
+ set +e
+ ${SUDO} -E -- sh -c "\"$0\" $* || exit 42"
+ case $? in
+ 1)
+ die "this script needs to run as root"
+ ;;
+ 42)
+ exit 1
+ ;;
+ *)
+ exit 0
+ ;;
+ esac
  fi
 else
  : "${SUDO_UID:=0}" "${SUDO_GID:=0}"

Meta/build-native-partition.sh

@@ -16,8 +16,19 @@ cleanup() {
 }
 
 if [ "$(id -u)" != 0 ]; then
- sudo -E -- "$0" "$@" || die "this script needs to run as root"
- exit 0
+ set +e
+ ${SUDO} -E -- sh -c "\"$0\" $* || exit 42"
+ case $? in
+ 1)
+ die "this script needs to run as root"
+ ;;
+ 42)
+ exit 1
+ ;;
+ *)
+ exit 0
+ ;;
+ esac
 else
  : "${SUDO_UID:=0}" "${SUDO_GID:=0}"
 fi