# $NetBSD: gendevcalls.awk,v 1.2 2024/02/09 22:08:37 andvar Exp $

#! /usr/bin/awk -f
# $NetBSD: gendevcalls.awk,v 1.2 2024/02/09 22:08:37 andvar Exp $
#
# Copyright (c) 2021 The NetBSD Foundation, Inc.
# All rights reserved.
#
# This code is derived from software contributed to The NetBSD Foundation
# by Jason R. Thorpe.
#
# Redistribution and use in source and binary forms, with or without
# modification, are permitted provided that the following conditions
# are met:
# 1. Redistributions of source code must retain the above copyright
# notice, this list of conditions and the following disclaimer.
# 2. Redistributions in binary form must reproduce the above copyright
# notice, this list of conditions and the following disclaimer in the
# documentation and/or other materials provided with the distribution.
#
# THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
# ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
# TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
# PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
# BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
# CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
# SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
# INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
# CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
# ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
# POSSIBILITY OF SUCH DAMAGE.
#

#
# Parses a device call definition file and produces argument and
# binding structures.
#

function emit_binding(field) {
printf("union %s_binding {\n", call_name_ub)
printf("\tstruct device_call_generic generic;\n")
if (field != "") {
printf("\tstruct {\n")
printf("\t\tconst char *name;\n")
printf("\t\tstruct %s_args *args;\n", call_name_ub)
printf("\t} %s;\n", field);
}
printf("};\n")
}

function emit_name_macro() {
printf("\n")
printf("#define %s_STR \"%s\"\n", call_name_ub_uc, call_name)
}

function emit_invoke_macro(field, marg, carg) {
printf("\n")
printf("#define %s%s \\\n", call_name_ub_uc, marg)
printf("\t&((const union %s_binding){ \\\n", call_name_ub)
printf("\t\t.%s.name = \"%s\", \\\n", field, call_name)
printf("\t\t.%s.args = %s, \\\n", field, carg)
printf("\t})\n")
}

function start_decl(arg) {
if (state == "expecting-subsystem") {
print "must declare a subsystem before declaring a call " \
"at line " NR \
> "/dev/stderr"
exit 1
}

if (state != "expecting-decl-start") {
print "unexpected start of declaration at line " NR \
> "/dev/stderr"
exit 1
}

call_name = arg

if (index(call_name, call_name_prefix) != 1) {
printf("method name '%s' at line %d must begin with '%s'\n", \
call_name, NR, call_name_prefix) \
> "/dev/stderr"
exit 1
}

call_name_ub = arg
gsub("\-", "_", call_name_ub)
call_name_ub_uc = toupper(call_name_ub)
}

NR == 1 {
VERSION = $0
gsub("\\$", "", VERSION)
gsub(/ $/, "", VERSION)

printf("/*\t$NetBSD" "$\t*/\n\n")
printf("/*\n")
printf(" * THIS FILE IS AUTOMATICALLY GENERATED. DO NOT EDIT.\n")
printf(" *\n")
printf(" * generated from:\n")
printf(" *\t%s\n", VERSION)
printf(" */\n")

subsystem = ""
state = "expecting-subsystem"

next
}
#
# Subsystem declaration. We use this to generate header file guards,
# as well as to sanity-check the method names when they are declared.
#
state == "expecting-subsystem" && \
/^subsystem[ \t]+[a-zA-Z]+[a-zA-Z0-9\-]*[ \t]*;[ \t]*$/ {
subsystem = $2

# strip the trailing ;
gsub(";$", "", subsystem)

subsystem_ub = subsystem
gsub("\-", "_", subsystem_ub)
subsystem_ub_uc = toupper(subsystem_ub)

# now tack on a trailing - for sanity checking method
# names later.
call_name_prefix = subsystem "-"

# Emit the leading header guard.
printf("#ifndef _%s_CALLS_H_\n", subsystem_ub_uc)
printf("#define _%s_CALLS_H_\n", subsystem_ub_uc)

# Pull in <sys/device.h> for 'struct device_call_generic'.
printf("\n#include <sys/device.h>\n")

state = "expecting-decl-start"

next
}
#
# Beginning of a call-with-arguments declaration. Gather up the various
# forms of the method name and emit the beginning of the structure declaration.
#
/^[a-zA-Z]+[a-zA-Z0-9\-]*[ \t]+{[ \t]*$/ {
start_decl($1)

# Emit the args structure declaration.
printf("struct %s_args {\n", call_name_ub)

state = "expecting-decl-end"

next
}
#
# A call-without-arguments declaration.
#
/^[a-zA-Z]+[a-zA-Z0-9\-]*[ \t]*;[ \t]*$/ {
# strip the trailing ;
call_name = $1
gsub(";$", "", call_name)

start_decl(call_name)

emit_binding("")
emit_name_macro()
emit_invoke_macro("generic", "", "NULL")

next
}
#
# End of a declaration. Wrap up the structure declaration and emit
# the binding information.
#
/^}[ \t]*;[ \t]*$/ {
if (state != "expecting-decl-end") {
print "unexpected end of declaration at line " NR \
> "/dev/stderr"
exit 1
}

# Terminate the args structure declaration.
printf("};\n")

printf("\n")
emit_binding("binding")
emit_name_macro()
emit_invoke_macro("binding", "(_args_)", "(_args_)")

state = "expecting-decl-start"

next
}
#
# Default action is to simply emit the line as it exists in the source
# file.
#
{
print $0
}
END {
if (state != "expecting-decl-start") {
print "unexpected end of file at line " NR \
> "/dev/stderr"
exit 1
}

# Emit the trailing header guard.
printf("\n#endif /* _%s_CALLS_H_ */\n", subsystem_ub_uc)
}