From 2edc9c6fd10e34ca1da0d25d3ceb9b67a6b9c73c Mon Sep 17 00:00:00 2001 From: Přemysl Eric Janouch Date: Fri, 7 Jul 2023 12:25:14 +0200 Subject: Add a C++ backend for LibertyXDR Also change the C backend so that it also de/serializes unions without any other fields besides the tag. --- tools/lxdrgen-cpp.awk | 350 ++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 350 insertions(+) create mode 100644 tools/lxdrgen-cpp.awk (limited to 'tools/lxdrgen-cpp.awk') diff --git a/tools/lxdrgen-cpp.awk b/tools/lxdrgen-cpp.awk new file mode 100644 index 0000000..825bba7 --- /dev/null +++ b/tools/lxdrgen-cpp.awk @@ -0,0 +1,350 @@ +# lxdrgen-cpp.awk: C++ backend for lxdrgen.awk. +# +# This backend is intended for Windows, it just happens to have a fallback +# that will probably work on Unices, of which we make use in tests. +# +# Copyright (c) 2023, Přemysl Eric Janouch +# SPDX-License-Identifier: 0BSD + +function define_internal(name, ctype) { + Types[name] = "internal" + CodegenCType[name] = ctype + CodegenSerialize[name] = \ + "\tw.append(%s);\n" + CodegenDeserialize[name] = \ + "\tif (!r.read(%s))\n" \ + "\t\treturn false;\n" +} + +function define_int(shortname, ctype) { + define_internal(shortname, ctype) +} + +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", "std::wstring") + define_internal("bool", "bool") + + CodegenSerialize["string"] = \ + "\tif (!w.append(%s))\n" \ + "\t\treturn false;\n" + + print "// Code generated from " FILENAME ". DO NOT EDIT." + print "" + print "#include " + print "#include " + print "#include " + print "#include " + print "" + print "namespace LibertyXDR {" + print "" + print "bool utf8_to_wstring(" + print "\tconst uint8_t *utf8, size_t length, std::wstring &wide);" + print "bool wstring_to_utf8(" + print "\tconst std::wstring &wide, std::string &utf8);" + print "" + print "struct Reader {" + print "\tconst uint8_t *data = {};" + print "\tsize_t length = {};" + print "" + print "\ttemplate bool read(T &number) {" + print "\t\tif (length < sizeof number)" + print "\t\t\treturn false;" + print "" + print "\t\tnumber = 0;" + print "\t\tfor (size_t i = 0; i < sizeof number; i++) {" + print "\t\t\tnumber = number << 8 | *data++;" + print "\t\t\tlength--;" + print "\t\t}" + print "\t\treturn true;" + print "\t}" + print "" + print "\tbool read(bool &boolean) {" + print "\t\tuint8_t number = 0;" + print "\t\tif (!read(number))" + print "\t\t\treturn false;" + print "" + print "\t\tboolean = number != 0;" + print "\t\treturn true;" + print "\t}" + print "" + print "\tbool read(std::wstring &string) {" + print "\t\tuint32_t size = 0;" + print "\t\tif (!read(size) || size > length)" + print "\t\t\treturn false;" + print "\t\tif (!utf8_to_wstring(data, size, string))" + print "\t\t\treturn false;" + print "" + print "\t\tdata += size;" + print "\t\tlength -= size;" + print "\t\treturn true;" + print "\t}" + print "" + print "\tbool read(std::vector &vector) {" + print "\t\tuint32_t size = 0;" + print "\t\tif (!read(size) || size > length)" + print "\t\t\treturn false;" + print "\t\tvector.assign(data, data + size);" + print "" + print "\t\tdata += size;" + print "\t\tlength -= size;" + print "\t\treturn true;" + print "\t}" + print "};" + print "" + print "struct Writer {" + print "\tstd::vector data;" + print "" + print "\ttemplate bool append(T number) {" + print "\t\tuint8_t buffer[sizeof number], *p = buffer + sizeof buffer;" + print "\t\twhile (p != buffer) {" + print "\t\t\t*--p = number;" + print "\t\t\tnumber >>= 8;" + print "\t\t}" + print "\t\tdata.insert(data.end(), buffer, buffer + sizeof buffer);" + print "\t\treturn true;" + print "\t}" + print "" + print "\tbool append(int8_t number) {" + print "\t\tdata.push_back(number);" + print "\t\treturn true;" + print "\t}" + print "" + print "\tbool append(uint8_t number) {" + print "\t\tdata.push_back(number);" + print "\t\treturn true;" + print "\t}" + print "" + print "\tbool append(bool boolean) {" + print "\t\treturn append(uint8_t(boolean));" + print "\t}" + print "" + print "\tbool append(const std::wstring &string) {" + print "\t\tif (string.size() > UINT32_MAX)" + print "\t\t\treturn false;" + print "" + print "\t\tstd::string utf8;" + print "\t\tif (!wstring_to_utf8(string, utf8))" + print "\t\t\treturn false;" + print "" + print "\t\tappend(utf8.size());" + print "\t\tdata.insert(data.end(), utf8.begin(), utf8.end());" + print "\t\treturn true;" + print "\t}" + print "};" + print "" + print "} // namespace LibertyXDR" + print "namespace " PrefixCamel " {" +} + +END { + print "" + print "} // namespace " PrefixCamel +} + +function codegen_constant(name, value) { + print "" + print "enum { " name " = " value " };" +} + +function codegen_enum_value(name, subname, value, cg) { + append(cg, "fields", "\t" subname " = " value ",\n") +} + +function codegen_enum(name, cg) { + print "" + print "enum struct " name " : int8_t {" + 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] = \ + "\tw.append(static_cast(%s));\n" + CodegenDeserialize[name] = \ + "\t{\n" \ + "\t\tint8_t v = 0;\n" \ + "\t\tif (!r.read(v) || !v)\n" \ + "\t\t\treturn false;\n" \ + "\t\t%s = static_cast<" name ">(v);\n" \ + "\t}\n" + + CodegenCType[name] = name + for (i in cg) + delete cg[i] +} + +# Some identifiers do not pose a problem in C, but do in our C++. +function codegen_struct_sanitize(name) { + if (name ~ /^(serialize|deserialize)_*$/ || + name ~ /^(catch|class|delete|except|finally|friend|new|operator)_*$/ || + name ~ /^(private|protected|public|template|this|throw|try|virtual)_*$/) + return name "_" + return name +} + +function codegen_struct_tag(d, cg, name, f) { + name = codegen_struct_sanitize(d["name"]) + f = "this->" name + + append(cg, "serialize", sprintf(CodegenSerialize[d["type"]], f)) + # Do not deserialize here, that would be out of order. +} + +function codegen_struct_field(d, cg, name, f, serialize, deserialize) { + name = codegen_struct_sanitize(d["name"]) + f = "this->" name + + serialize = CodegenSerialize[d["type"]] + deserialize = CodegenDeserialize[d["type"]] + if (!d["isarray"]) { + append(cg, "fields", + "\t" CodegenCType[d["type"]] " " name " = {};\n") + append(cg, "serialize", sprintf(serialize, f)) + append(cg, "deserialize", sprintf(deserialize, f)) + return + } + + append(cg, "fields", + "\tstd::vector<" CodegenCType[d["type"]] "> " name ";\n") + + # XXX: We should probably pedantically check for overflows. + append(cg, "serialize", + sprintf(CodegenSerialize["u32"], "uint32_t(" f ".size())") \ + "\tfor (const auto &it : " f ")\n" \ + indent(sprintf(serialize, "it"))) + + if (d["type"] == "u8") { + append(cg, "deserialize", + "\tif (!r.read(" f "))\n" \ + "\t\treturn false;\n") + } else if (deserialize) { + append(cg, "deserialize", + "\t{\n" \ + "\t\tuint32_t size = 0;\n" \ + indent(sprintf(CodegenDeserialize["u32"], "size")) \ + "\t\t" f ".resize(size);\n" \ + "\t}\n" \ + "\tfor (auto &it : " f ")\n" \ + indent(sprintf(deserialize, "it"))) + } +} + +function codegen_struct(name, cg) { + print "" + print "struct " name " {" + print cg["fields"] + print "\tbool serialize(LibertyXDR::Writer &w) const {" + print indent(cg["serialize"]) "\t\treturn true;" + print "\t}" + print "" + print "\tbool deserialize([[maybe_unused]] LibertyXDR::Reader &r) {" + print indent(cg["deserialize"]) "\t\treturn true;" + print "\t}" + print "};" + + CodegenSerialize[name] = "\tif (!%s->serialize(w))\n" \ + "\t\treturn false;\n" + CodegenDeserialize[name] = "\tif (!%s->deserialize(r))\n" \ + "\t\treturn false;\n" + + CodegenCType[name] = name + for (i in cg) + delete cg[i] +} + +function codegen_union_tag(name, d, cg, tagname) { + cg["tagtype"] = d["type"] + cg["tagname"] = tagname = codegen_struct_sanitize(d["name"]) + + print "" + print "struct " name " {" + print "\t" CodegenCType[d["type"]] " " tagname " = {};" + print "\tvirtual ~" name "() = 0;" + print "\tvirtual bool serialize(LibertyXDR::Writer &w) const = 0;" + print "\tvirtual bool deserialize(LibertyXDR::Reader &r) = 0;" + print "};" + print "" + print name "::~" name "() {}" +} + +function codegen_union_struct(name, casename, cg, scg, structname) { + # And thus not all generated structs are present in Types. + structname = name "_" snaketocamel(casename) + + print "" + print "struct " structname " : virtual public " name " {" + print scg["fields"] + print "\t" structname "() {" + print "\t\tthis->" cg["tagname"] " = " \ + CodegenCType[cg["tagtype"]] "::" casename ";" + print "\t}" + print "" + print "\tvirtual bool serialize(LibertyXDR::Writer &w) const {" + print indent(scg["serialize"]) "\t\treturn true;" + print "\t}" + print "" + print "\tvirtual bool deserialize([[maybe_unused]] LibertyXDR::Reader &r) {" + print indent(scg["deserialize"]) "\t\treturn true;" + print "\t}" + print "};" + + append(cg, "deserialize", + "\tcase " CodegenCType[cg["tagtype"]] "::" casename ":\n" \ + "\t\treturn new " structname "();\n") + + CodegenSerialize[structname] = "\tif (!%s->serialize(w))\n" \ + "\t\treturn false;\n" + CodegenDeserialize[structname] = "\tif (!%s->deserialize(r))\n" \ + "\t\treturn false;\n" + + CodegenCType[structname] = structname + for (i in scg) + delete scg[i] +} + +function codegen_union(name, cg, exhaustive, ctype) { + CodegenSerialize[name] = "\tif (!%s->serialize(w))\n" \ + "\t\treturn false;\n" + + ctype = "std::unique_ptr<" name ">" + if (cg["deserialize"]) { + print "" + print "static " name " *read" name "(" \ + CodegenCType[cg["tagtype"]] " " cg["tagname"] ") {" + print "\tswitch (" cg["tagname"] ") {" + print cg["deserialize"] "\tdefault:" + print "\t\treturn nullptr;" + print "\t}" + print "}" + print "" + print "static " ctype " read" name "(LibertyXDR::Reader &r) {" + print "\tint8_t v = 0;" + print "\tif (!r.read(v) || !v)" + print "\t\treturn nullptr;" + print "" + print "\t" ctype " result(read" name "(static_cast<" \ + CodegenCType[cg["tagtype"]] ">(v)));" + print "\tif (!result || !result->deserialize(r))" + print "\t\treturn nullptr;" + print "\treturn result;" + print "}" + + CodegenDeserialize[name] = "\tif (!(%s = read" name "(r)))\n" \ + "\t\treturn false;\n" + } + + CodegenCType[name] = ctype + for (i in cg) + delete cg[i] +} -- cgit v1.2.3-54-g00ecf