blob: 20f9f421f2b25cea62eb49c76ba48fce9f69e965 [file] [log] [blame]
#!/bin/sh
# Copyright 2015 The Chromium OS Authors. All rights reserved.
# Use of this source code is governed by a BSD-style license that can be
# found in the LICENSE file.
# Generates a header file with a named constant table made up of "name", value
# entries by including several build target header files and emitting the list
# of defines. Use of the preprocessor is needed to recursively include all
# relevant headers.
set -e
if [ $# -ne 1 ] && [ $# -ne 2 ]; then
echo "Usage: $(basename "$0") OUTFILE"
echo "Usage: $(basename "$0") INFILE OUTFILE"
exit 1
fi
BUILD="${CC} -dD ${SRC:-.}/gen_constants.c -E"
GEN_DEPS=1
if [ $# -eq 2 ]; then
BUILD="cat $1"
GEN_DEPS=0
shift
fi
OUTFILE="$1"
if [ ${GEN_DEPS} -eq 1 ]; then
# Generate a dependency file which helps the build tool to see when it
# should regenerate ${OUTFILE}.
${BUILD} -M -MF "${OUTFILE}.d"
fi
# sed expression which extracts constants and converts them from:
# #define AT_FDWCD foo
# to:
# #ifdef AT_FDCWD
# { "AT_FDWCD", AT_FDCWD },
# endif
SED_MULTILINE='s@#define ([[:upper:]][[:upper:]0-9_]*).*@#ifdef \1\
{ "\1", (unsigned long) \1 },\
#endif // \1@'
# Passes the previous list of #includes to the C preprocessor and prints out
# all #defines whose name is all-caps. Excludes a few symbols that are known
# macro functions that don't evaluate to a constant.
cat <<-EOF > "${OUTFILE}"
/* GENERATED BY MAKEFILE */
#include "gen_constants-inl.h"
#include "libconstants.h"
const struct constant_entry constant_table[] = {
$(${BUILD} | \
grep -E '^#define [[:upper:]][[:upper:]0-9_]*[[:space:]]+[[:alnum:]_]' | \
grep -Ev '(SIGRTMAX|SIGRTMIN|SIG_|NULL)' | \
sort -u | \
sed -Ee "${SED_MULTILINE}")
{ NULL, 0 },
};
EOF