# Generate SYS_* macros from a list in a text file.

# Copyright (C) 2017-2018 Free Software Foundation, Inc.

# This file is part of the GNU C Library.

#

# The GNU C Library is free software; you can redistribute it and/or

# modify it under the terms of the GNU Lesser General Public

# License as published by the Free Software Foundation; either

# version 2.1 of the License, or (at your option) any later version.

#

# The GNU C Library is distributed in the hope that it will be useful,

# but WITHOUT ANY WARRANTY; without even the implied warranty of

# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU

# Lesser General Public License for more details.

#

# You should have received a copy of the GNU Lesser General Public

# License along with the GNU C Library; if not, see

# <http://www.gnu.org/licenses/>.

# Emit a conditional definition for SYS_NAME.

function emit(name) {

    print "#ifdef __NR_" name;

    print "# define SYS_" name " __NR_" name;

    print "#endif";

    print "";

}

# Bail out with an error.

function fatal(message) {

    print FILENAME ":" FNR ": " message > "/dev/stderr";

    exit 1;

}

BEGIN {

    name = "";

    kernel = "";

}

# Skip empty lines and comments.

/^\s*(|#.*)$/ {

    next;

}

# Kernel version.  Used for documentation purposes only.

/^kernel [0-9.]+$/ {

    if (kernel != "") {

        fatal("duplicate kernel directive");

    }

    kernel = $2;

    print "/* Generated at libc build time from syscall list.  */";

    print "/* The system call list corresponds to kernel " kernel ".  */";

    print "";

    print "#ifndef _SYSCALL_H"

    print "# error \"Never use <bits/syscall.h> directly; include <sys/syscall.h> instead.\"";

    print "#endif";

    print "";

    split($2, kernel_version, ".");

    kernel_major = kernel_version[1];

    kernel_minor = kernel_version[2];

    kernel_version_code = kernel_major * 65536 + kernel_minor * 256;

    print "#define __GLIBC_LINUX_VERSION_CODE " kernel_version_code;

    print "";

    next;

}

# If there is just one word, it is a system call.

/^[a-zA-Z_][a-zA-Z0-9_]+$/ {

    if (kernel == "") {

        fatal("expected kernel directive before this line");

    }

    if ($1 <= name) {

        fatal("name " name " violates ordering");

    }

    emit($1);

    name = $1;

    next;

}

# The rest has to be syntax errors.

// {

    fatal("unrecognized syntax");

}