#!/bin/sh
  # SPDX-License-Identifier: GPL-2.0-only
  #
  # Generate a syscall number header.
  #
  # Each line of the syscall table should have the following format:
  #
  # NR ABI NAME [NATIVE] [COMPAT]
  #
  # NR       syscall number
  # ABI      ABI name
  # NAME     syscall name
  # NATIVE   native entry point (optional)
  # COMPAT   compat entry point (optional)
  set -e
  
  usage() {
  	echo >&2 "usage: $0 [--abis ABIS] [--prefix PREFIX] INFILE OUTFILE" >&2
  	echo >&2
  	echo >&2 "  INFILE    input syscall table"
  	echo >&2 "  OUTFILE   output header file"
  	echo >&2
  	echo >&2 "options:"
  	echo >&2 "  --abis ABIS        ABI(s) to handle (By default, all lines are handled)"
  	echo >&2 "  --prefix PREFIX    The prefix to the macro like __NR_<PREFIX><NAME>"
  	exit 1
  }
  
  # default unless specified by options
  abis=
  prefix=
  
  while [ $# -gt 0 ]
  do
  	case $1 in
  	--abis)
  		abis=$(echo "($2)" | tr ',' '|')
  		shift 2;;
  	--prefix)
  		prefix=$2
  		shift 2;;
  	-*)
  		echo "$1: unknown option" >&2
  		usage;;
  	*)
  		break;;
  	esac
  done
  
  if [ $# -ne 2 ]; then
  	usage
  fi
  
  infile="$1"
  outfile="$2"
  
  guard=_ASM_$(basename "$outfile" |
  	sed -e 'y/abcdefghijklmnopqrstuvwxyz/ABCDEFGHIJKLMNOPQRSTUVWXYZ/' \
  	-e 's/[^A-Z0-9_]/_/g' -e 's/__/_/g')
  
  grep -E "^[0-9A-Fa-fXx]+[[:space:]]+$abis" "$infile" | sort -n | {
  	echo "#ifndef $guard"
  	echo "#define $guard"
  	echo
  
  	max=0
  	while read nr abi name native compat ; do
  		max=$nr
  	done
  
  	echo "#define __NR_${prefix}syscalls $(($max + 1))"
  	echo
  	echo "#endif /* $guard */"
  } > "$outfile"