xK/xC-gen-proto-c.awk

326 lines
9.6 KiB
Awk

# xC-gen-proto-c.awk: C backend for xC-gen-proto.awk.
#
# Copyright (c) 2022, Přemysl Eric Janouch <p@janouch.name>
# SPDX-License-Identifier: 0BSD
#
# Neither *_new() nor *_destroy() functions are provided, because they'd only
# be useful for top-levels, and are merely extra malloc()/free() calls.
# Users are expected to reuse buffers.
#
# Similarly, no constructors are produced--those are easy to write manually.
#
# All arrays are deserialized zero-terminated, so u8<> and i8<> can be directly
# used as C strings.
#
# All types must be able to dispose partially zero values going from the back,
# i.e., in the reverse order of deserialization.
function define_internal(name, ctype) {
Types[name] = "internal"
CodegenCType[name] = ctype
}
function define_int(shortname, ctype) {
define_internal(shortname, ctype)
CodegenSerialize[shortname] = \
"\tstr_pack_" shortname "(w, %s);\n"
CodegenDeserialize[shortname] = \
"\tif (!msg_unpacker_" shortname "(r, &%s))\n" \
"\t\treturn false;\n"
}
function define_sint(size) { define_int("i" size, "int" size "_t") }
function define_uint(size) { define_int("u" size, "uint" size "_t") }
function codegen_begin() {
define_sint("8")
define_sint("16")
define_sint("32")
define_sint("64")
define_uint("8")
define_uint("16")
define_uint("32")
define_uint("64")
define_internal("string", "struct str")
CodegenDispose["string"] = "\tstr_free(&%s);\n"
CodegenSerialize["string"] = \
"\tif (!proto_string_serialize(&%s, w))\n" \
"\t\treturn false;\n"
CodegenDeserialize["string"] = \
"\tif (!proto_string_deserialize(&%s, r))\n" \
"\t\treturn false;\n"
define_internal("bool", "bool")
CodegenSerialize["bool"] = \
"\tstr_pack_u8(w, !!%s);\n"
CodegenDeserialize["bool"] = \
"\t{\n" \
"\t\tuint8_t v = 0;\n" \
"\t\tif (!msg_unpacker_u8(r, &v))\n" \
"\t\t\treturn false;\n" \
"\t\t%s = !!v;\n" \
"\t}\n"
print "// This file directly depends on liberty.c, but doesn't include it."
print ""
print "static bool"
print "proto_string_serialize(const struct str *s, struct str *w) {"
print "\tif (s->len > UINT32_MAX)"
print "\t\treturn false;"
print "\tstr_pack_u32(w, s->len);"
print "\tstr_append_str(w, s);"
print "\treturn true;"
print "}"
print ""
print "static bool"
print "proto_string_deserialize(struct str *s, struct msg_unpacker *r) {"
print "\tuint32_t len = 0;"
print "\tif (!msg_unpacker_u32(r, &len))"
print "\t\treturn false;"
print "\tif (msg_unpacker_get_available(r) < len)"
print "\t\treturn false;"
print "\t*s = str_make();"
print "\tstr_append_data(s, r->data + r->offset, len);"
print "\tr->offset += len;"
print "\tif (!utf8_validate (s->str, s->len))"
print "\t\treturn false;"
print "\treturn true;"
print "}"
}
function codegen_constant(name, value) {
print ""
print "enum { " PrefixUpper name " = " value " };"
}
function codegen_enum_value(name, subname, value, cg) {
append(cg, "fields",
"\t" PrefixUpper toupper(cameltosnake(name)) "_" subname \
" = " value ",\n")
}
function codegen_enum(name, cg, ctype) {
ctype = "enum " PrefixLower cameltosnake(name)
print ""
print ctype " {"
print cg["fields"] "};"
# XXX: This should also check if it isn't out-of-range for any reason,
# but our usage of sprintf() stands in the way a bit.
CodegenSerialize[name] = "\tstr_pack_i8(w, %s);\n"
CodegenDeserialize[name] = \
"\t{\n" \
"\t\tint8_t v = 0;\n" \
"\t\tif (!msg_unpacker_i8(r, &v) || !v)\n" \
"\t\t\treturn false;\n" \
"\t\t%s = v;\n" \
"\t}\n"
CodegenCType[name] = ctype
for (i in cg)
delete cg[i]
}
function codegen_struct_tag(d, cg, f) {
f = "self->" d["name"]
append(cg, "fields", "\t" CodegenCType[d["type"]] " " d["name"] ";\n")
append(cg, "dispose", sprintf(CodegenDispose[d["type"]], f))
append(cg, "serialize", sprintf(CodegenSerialize[d["type"]], f))
# Do not deserialize here, that would be out of order.
}
function codegen_struct_field(d, cg, f, dispose, serialize, deserialize) {
f = "self->" d["name"]
dispose = CodegenDispose[d["type"]]
serialize = CodegenSerialize[d["type"]]
deserialize = CodegenDeserialize[d["type"]]
if (!d["isarray"]) {
append(cg, "fields", "\t" CodegenCType[d["type"]] " " d["name"] ";\n")
append(cg, "dispose", sprintf(dispose, f))
append(cg, "serialize", sprintf(serialize, f))
append(cg, "deserialize", sprintf(deserialize, f))
return
}
append(cg, "fields",
"\t" CodegenCType["u32"] " " d["name"] "_len;\n" \
"\t" CodegenCType[d["type"]] " *" d["name"] ";\n")
if (dispose)
append(cg, "dispose", "\tif (" f ")\n" \
"\t\tfor (size_t i = 0; i < " f "_len; i++)\n" \
indent(indent(sprintf(dispose, f "[i]"))))
append(cg, "dispose", "\tfree(" f ");\n")
append(cg, "serialize", sprintf(CodegenSerialize["u32"], f "_len"))
if (d["type"] == "u8" || d["type"] == "i8") {
append(cg, "serialize",
"\tstr_append_data(w, " f ", " f "_len);\n")
} else if (serialize) {
append(cg, "serialize",
"\tfor (size_t i = 0; i < " f "_len; i++)\n" \
indent(sprintf(serialize, f "[i]")))
}
append(cg, "deserialize", sprintf(CodegenDeserialize["u32"], f "_len") \
"\tif (!(" f " = calloc(" f "_len + 1, sizeof *" f ")))\n" \
"\t\treturn false;\n")
if (d["type"] == "u8" || d["type"] == "i8") {
append(cg, "deserialize",
"\tif (msg_unpacker_get_available(r) < " f "_len)\n" \
"\t\treturn false;\n" \
"\tmemcpy(" f ", r->data + r->offset, " f "_len);\n" \
"\tr->offset += " f "_len;\n")
} else if (deserialize) {
append(cg, "deserialize",
"\tfor (size_t i = 0; i < " f "_len; i++)\n" \
indent(sprintf(deserialize, f "[i]")))
}
}
function codegen_struct(name, cg, ctype, funcname) {
ctype = "struct " PrefixLower cameltosnake(name)
print ""
print ctype " {"
print cg["fields"] "};"
if (cg["dispose"]) {
funcname = PrefixLower cameltosnake(name) "_free"
print ""
print "static void\n" funcname "(" ctype " *self) {"
print cg["dispose"] "}"
CodegenDispose[name] = "\t" funcname "(&%s);\n"
}
if (cg["serialize"]) {
funcname = PrefixLower cameltosnake(name) "_serialize"
print ""
print "static bool\n" \
funcname "(\n\t\t" ctype " *self, struct str *w) {"
print cg["serialize"] "\treturn true;"
print "}"
CodegenSerialize[name] = "\tif (!" funcname "(&%s, w))\n" \
"\t\treturn false;\n"
}
if (cg["deserialize"]) {
funcname = PrefixLower cameltosnake(name) "_deserialize"
print ""
print "static bool\n" \
funcname "(\n\t\t" ctype " *self, struct msg_unpacker *r) {"
print cg["deserialize"] "\treturn true;"
print "}"
CodegenDeserialize[name] = "\tif (!" funcname "(&%s, r))\n" \
"\t\treturn false;\n"
}
CodegenCType[name] = ctype
for (i in cg)
delete cg[i]
}
function codegen_union_tag(d, cg) {
cg["tagtype"] = d["type"]
cg["tagname"] = d["name"]
append(cg, "fields", "\t" CodegenCType[d["type"]] " " d["name"] ";\n")
}
function codegen_union_struct( \
name, casename, cg, scg, structname, fieldname, fullcasename) {
# Don't generate obviously useless structs.
fullcasename = toupper(cameltosnake(cg["tagtype"])) "_" casename
if (!scg["dispose"] && !scg["deserialize"]) {
append(cg, "structless", "\tcase " PrefixUpper fullcasename ":\n")
for (i in scg)
delete scg[i]
return
}
# And thus not all generated structs are present in Types.
structname = name "_" casename
fieldname = tolower(casename)
codegen_struct(structname, scg)
append(cg, "fields", "\t" CodegenCType[structname] " " fieldname ";\n")
if (CodegenDispose[structname])
append(cg, "dispose", "\tcase " PrefixUpper fullcasename ":\n" \
indent(sprintf(CodegenDispose[structname], "self->" fieldname)) \
"\t\tbreak;\n")
# With no de/serialization code, this will simply recognize the tag.
append(cg, "serialize", "\tcase " PrefixUpper fullcasename ":\n" \
indent(sprintf(CodegenSerialize[structname], "self->" fieldname)) \
"\t\tbreak;\n")
append(cg, "deserialize", "\tcase " PrefixUpper fullcasename ":\n" \
indent(sprintf(CodegenDeserialize[structname], "self->" fieldname)) \
"\t\tbreak;\n")
}
function codegen_union(name, cg, f, ctype, funcname) {
ctype = "union " PrefixLower cameltosnake(name)
print ""
print ctype " {"
print cg["fields"] "};"
f = "self->" cg["tagname"]
if (cg["dispose"]) {
funcname = PrefixLower cameltosnake(name) "_free"
print ""
print "static void\n" funcname "(" ctype " *self) {"
print "\tswitch (" f ") {"
if (cg["structless"])
print cg["structless"] \
indent(sprintf(CodegenDispose[cg["tagtype"]], f)) "\t\tbreak;"
print cg["dispose"] "\tdefault:"
print "\t\tbreak;"
print "\t}"
print "}"
CodegenDispose[name] = "\t" funcname "(&%s);\n"
}
if (cg["serialize"]) {
funcname = PrefixLower cameltosnake(name) "_serialize"
print ""
print "static bool\n" \
funcname "(\n\t\t" ctype " *self, struct str *w) {"
print "\tswitch (" f ") {"
if (cg["structless"])
print cg["structless"] \
indent(sprintf(CodegenSerialize[cg["tagtype"]], f)) "\t\tbreak;"
print cg["serialize"] "\tdefault:"
print "\t\treturn false;"
print "\t}"
print "\treturn true;"
print "}"
CodegenSerialize[name] = "\tif (!" funcname "(&%s, w))\n" \
"\t\treturn false;\n"
}
if (cg["deserialize"]) {
funcname = PrefixLower cameltosnake(name) "_deserialize"
print ""
print "static bool\n" \
funcname "(\n\t\t" ctype " *self, struct msg_unpacker *r) {"
print sprintf(CodegenDeserialize[cg["tagtype"]], f)
print "\tswitch (" f ") {"
if (cg["structless"])
print cg["structless"] "\t\tbreak;"
print cg["deserialize"] "\tdefault:"
print "\t\treturn false;"
print "\t}"
print "\treturn true;"
print "}"
CodegenDeserialize[name] = "\tif (!" funcname "(&%s, r))\n" \
"\t\treturn false;\n"
}
CodegenCType[name] = ctype
for (i in cg)
delete cg[i]
}