#!@PYTHON@ # Copyright (C) 2010-2021 Internet Systems Consortium, Inc. ("ISC") # # This Source Code Form is subject to the terms of the Mozilla Public # License, v. 2.0. If a copy of the MPL was not distributed with this # file, You can obtain one at http://mozilla.org/MPL/2.0/. """\ This is a supplemental script to (half) auto-generate DNS Rdata related classes and constants. """ # This script should be used every time existing RR data changes or when new # RR types are added or existing are removed. Since DHCP uses only four # (A,AAAA,PTR,DHCID) RR types, its usage is expected to be an uncommon event. # The only envisaged use case is if/when we decide to trim down libdns++. import os from os.path import getmtime import re import sys re_typecode = re.compile('([\da-z\-]+)_(\d+)') classcode2txt = {} typecode2txt = {} # For meta types and types well-known but not implemented. This is a dict from # type code values (as string) to textual mnemonic. meta_types = { # Real meta types. We won't have Rdata implement for them, but we need # RRType constants. '251': 'ixfr', '252': 'axfr', '255': 'any', # Obsolete types. We probably won't implement Rdata for them, but it's # better to have RRType constants. '3': 'md', '4': 'mf', '7': 'mb', '8': 'mg', '9': 'mr', '30': 'nxt', '38': 'a6', '254': 'maila', # Types officially assigned but not yet supported in our implementation. '10': 'null', '11': 'wks', '19': 'x25', '21': 'rt', '22': 'nsap', '23': 'nsap-ptr', '24': 'sig', '20': 'isdn', '25': 'key', '26': 'px', '27': 'gpos', '29': 'loc', '36': 'kx', '37': 'cert', '42': 'apl', '45': 'ipseckey', '55': 'hip', '103': 'unspec', '104': 'nid', '105': 'l32', '106': 'l64', '107': 'lp', '253': 'mailb', '256': 'uri' } # Classes that don't have any known types. This is a dict from type code # values (as string) to textual mnemonic. meta_classes = {'254': 'none'} typeandclass = [] generic_code = 65536 # something larger than any code value rdata_declarations = '' class_definitions = '' classdir_mtime = 0 rdatadef_mtime = 0 rdatahdr_mtime = 0 heading_txt = '''/////////////// /////////////// /////////////// THIS FILE IS AUTOMATICALLY GENERATED BY gen-rdatacode.py. /////////////// DO NOT EDIT! /////////////// /////////////// ''' def import_classdef(class_txt, file): content = '' rdata_source = open(file, 'r') for line in rdata_source.readlines(): if re.match('// BEGIN_ISC_NAMESPACE', line): content += 'namespace isc {\n' content += 'namespace dns {\n' continue if re.match('// BEGIN_RDATA_NAMESPACE', line): content += 'namespace rdata {\n' content += 'namespace ' + class_txt + ' {\n' continue if re.match('// END_ISC_NAMESPACE', line): content += '} // end of namespace "dns"\n' content += '} // end of namespace "isc"\n' continue if re.match('// END_RDATA_NAMESPACE', line): content += '} // end of namespace "' + class_txt +'"\n' content += '} // end of namespace "rdata"\n' continue content += line rdata_source.close() return content def import_classheader(class_txt, type_txt, type_code, file): type_utxt = type_txt.upper() class_utxt = class_txt.upper() # for each CLASS_n/TYPE_m.h rdata_header = open(file, 'r') content = '' guard_macro = class_txt.upper() + '_' + type_txt.upper() guard_macro += '_' + type_code + '_H' for line in rdata_header.readlines(): if re.match('// BEGIN_HEADER_GUARD', line): content += '#ifndef ' + guard_macro + '\n' content += '#define ' + guard_macro + ' 1\n' continue if re.match('// END_HEADER_GUARD', line): content += '#endif // ' + guard_macro + '\n' continue if re.match('// BEGIN_ISC_NAMESPACE', line): content += 'namespace isc {\n' content += 'namespace util {\n' content += ''' class InputBuffer; class OutputBuffer;\n''' content += '}\n\n' content += 'namespace dns {\n' continue if re.match('// BEGIN_RDATA_NAMESPACE', line): content += 'namespace rdata {\n' content += 'namespace ' + class_txt + ' {\n' continue if re.match('// END_ISC_NAMESPACE', line): content += '} // end of namespace "dns"\n' content += '} // end of namespace "isc"\n' continue if re.match('// END_RDATA_NAMESPACE', line): content += '} // end of namespace "' + class_txt +'"\n' content += '} // end of namespace "rdata"\n' continue if re.match('// Local Variables:', line): break content += line if re.match('// BEGIN_COMMON_DECLARATIONS', line): content += ''' class AbstractMessageRenderer;\n\n''' if re.match('\s+// BEGIN_COMMON_MEMBERS$', line): content += ''' explicit ''' + type_utxt + '''(const std::string& type_str); ''' + type_utxt + '''(isc::util::InputBuffer& buffer, size_t rdata_len); ''' + type_utxt + '''(const ''' + type_utxt + '''& other); ''' + type_utxt + '''( MasterLexer& lexer, const Name* name, MasterLoader::Options options, MasterLoaderCallbacks& callbacks); virtual std::string toText() const; virtual void toWire(isc::util::OutputBuffer& buffer) const; virtual void toWire(AbstractMessageRenderer& renderer) const; virtual int compare(const Rdata& other) const;\n\n''' rdata_header.close() return content def import_definitions(classcode2txt, typecode2txt, typeandclass): global rdata_declarations global class_definitions global classdir_mtime global rdatadef_mtime global rdatahdr_mtime if classdir_mtime < getmtime('@srcdir@/rdata'): classdir_mtime = getmtime('@srcdir@/rdata') # Sort directories before iterating through them so that the directory # list is processed in the same order on all systems. The resulting # files should compile regardless of the order in which the components # are included but... Having a fixed order for the directories should # eliminate system-dependent problems. (Note that the directory names # in BIND 10 are ASCII, so the order should be locale-independent.) dirlist = os.listdir('@srcdir@/rdata') dirlist.sort() for dir in dirlist: classdir = '@srcdir@/rdata' + os.sep + dir m = re_typecode.match(dir) if os.path.isdir(classdir) and (m != None or dir == 'generic'): if dir == 'generic': class_txt = 'generic' class_code = generic_code else: class_txt = m.group(1) class_code = m.group(2) if not class_code in classcode2txt: classcode2txt[class_code] = class_txt # Same considerations as directories regarding sorted order # also apply to files. filelist = os.listdir(classdir) filelist.sort() for file in filelist: file = classdir + os.sep + file m = re_typecode.match(os.path.split(file)[1]) if m != None: type_txt = m.group(1) type_code = m.group(2) if not type_code in typecode2txt: typecode2txt[type_code] = type_txt if re.search('\.cc$', file): if rdatadef_mtime < getmtime(file): rdatadef_mtime = getmtime(file) class_definitions += import_classdef(class_txt, file) elif re.search('\.h$', file): if rdatahdr_mtime < getmtime(file): rdatahdr_mtime = getmtime(file) rdata_declarations += import_classheader(class_txt, type_txt, type_code, file) typeandclass.append((type_txt, int(type_code), (class_txt, class_txt), int(class_code))) if class_txt == 'generic': typeandclass.append((type_txt, int(type_code), (class_txt, 'in'), 1)) def need_generate(file, mtime): '''Check if we need to generate the specified file. To avoid unnecessary compilation, we skip (re)generating the file when the file already exists and newer than the base file. ''' if os.path.exists(file) and getmtime(file) > mtime: return False return True def generate_rdatadef(file, basemtime): if not need_generate(file, basemtime): print('skip generating ' + file); return rdata_deffile = open(file, 'w') rdata_deffile.write(heading_txt) rdata_deffile.write(class_definitions) rdata_deffile.close() def generate_rdatahdr(file, heading, declarations, basemtime): if not need_generate(file, basemtime): print('skip generating ' + file); return heading += ''' #ifndef DNS_RDATACLASS_H #define DNS_RDATACLASS_H 1 #include namespace isc { namespace dns { class Name; class MasterLexer; class MasterLoaderCallbacks; } } ''' declarations += ''' #endif // DNS_RDATACLASS_H // Local Variables: // mode: c++ // End: ''' rdata_header = open(file, 'w') rdata_header.write(heading) rdata_header.write(declarations) rdata_header.close() def generate_typeclasscode(fileprefix, basemtime, code2txt, type_or_class): placeholder = '@srcdir@/' + fileprefix + '-placeholder.h' outputfile = '@builddir@/' + fileprefix + '.h' py_outputfile = '@builddir@/python/' + fileprefix + '_constants_inc.cc' upper_key = type_or_class.upper() # TYPE or CLASS lower_key = 'rr' + type_or_class.lower() # rrtype or rrclass cap_key = type_or_class # Type or Class # We only decide whether to generate files for libdns++ files; Python # files are generated if and only if libdns++ files are generated. # In practice it should be sufficient. if (not need_generate(outputfile, basemtime) and getmtime(outputfile) > getmtime(placeholder)): print('skip generating ' + outputfile) return # Create a list of (code, code-text) pairs, where code-text is generally # upper-cased, with applying special filters when necessary. def convert(code_txt): # Workaround by heuristics: there's a "NULL" RR type, but it would # cause conflict with the C/C++ macro. We use Null as a special case. if code_txt == 'null': return 'Null' # Likewise, convert "nsap-ptr" to "NSAP_PTR" as a dash cannot be part # of a C/C++ variable. if code_txt == 'nsap-ptr': return 'NSAP_PTR' return code_txt.upper() codes = [ (code, convert(txt)) for code, txt in code2txt.items() ] # Dump source code for libdns++ with open(placeholder, 'r') as header_temp: with open(outputfile, 'w') as header_out: header_out.write(heading_txt) for line in header_temp: header_out.write(line) if re.match('\s+// BEGIN_WELL_KNOWN_' + upper_key + '_DECLARATIONS$', line): for code in codes: header_out.write(' ' * 4 + 'static const RR' + cap_key + '& ' + code[1] + '();\n') if re.match('// BEGIN_WELL_KNOWN_' + upper_key + '_DEFINITIONS$', line): for code in codes: header_out.write('''inline const RR''' + cap_key + '''& RR''' + cap_key + '''::''' + code[1] + '''() { static RR''' + cap_key + ''' ''' + lower_key + '''(''' + code[0] + '''); return (''' + lower_key + '''); }\n ''') # Dump source code snippet for isc.dns Python module with open(py_outputfile, 'w') as py_out: py_out.write(" // auto-generated by ../gen-rdatacode.py." " Don't edit this file.\n") py_out.write("\n") for code in codes: py_out.write('''\ installClassVariable(''' + lower_key + '''_type, "''' + code[1] + '''", createRR''' + cap_key + '''Object(RR''' + \ cap_key + '''::''' + code[1] + '''())); ''') def generate_rrparam(fileprefix, basemtime): placeholder = '@srcdir@/' + fileprefix + '-placeholder.cc' outputfile = '@builddir@/' + fileprefix + '.cc' if not need_generate(outputfile, basemtime) and getmtime(outputfile) > getmtime(placeholder): print('skip generating ' + outputfile) return # sort by class, then by type typeandclassparams = '' typeandclass.sort(key = lambda x: (x[3], x[1])) for param in typeandclass: # for rrparamregistry.cc # each param is a tuple of (type_txt, type_code, class_tuple, # class_code) (type_txt, type_code, class_tuple, class_code) = param type_utxt = type_txt.upper() class_txt = class_tuple[0] class_utxt = class_tuple[1].upper() indent = ' ' * 8 typeandclassparams += indent if class_tuple[1] != 'generic': typeandclassparams += 'add("' + type_utxt + '", ' typeandclassparams += str(type_code) + ', "' + class_utxt typeandclassparams += '", ' + str(class_code) typeandclassparams += ', RdataFactoryPtr(new ' + 'RdataFactory' + '<' typeandclassparams += class_txt + '::' + type_utxt + '>()));\n' else: typeandclassparams += 'add("' + type_utxt + '", ' + str(type_code) typeandclassparams += ', RdataFactoryPtr(new ' + 'RdataFactory' + '<' typeandclassparams += class_txt + '::' + type_utxt + '>()));\n' typeandclassparams += indent + '// Meta and non-implemented RR types\n' for type_code, type_txt in meta_types.items(): typeandclassparams += indent + \ 'addType("' + type_txt.upper() + '", ' + type_code + ');\n' typeandclassparams += indent + '// Meta classes\n' for cls_code, cls_txt in meta_classes.items(): typeandclassparams += indent + \ 'addClass("' + cls_txt.upper() + '", ' + cls_code + ');\n' rrparam_temp = open(placeholder, 'r') rrparam_out = open(outputfile, 'w') rrparam_out.write(heading_txt) for line in rrparam_temp.readlines(): rrparam_out.write(line) if re.match('\s+// BEGIN_WELL_KNOWN_PARAMS', line): rrparam_out.write(typeandclassparams) rrparam_temp.close() rrparam_out.close() if __name__ == "__main__": try: import_definitions(classcode2txt, typecode2txt, typeandclass) generate_rdatadef('@builddir@/rdataclass.cc', rdatadef_mtime) generate_rdatahdr('@builddir@/rdataclass.h', heading_txt, rdata_declarations, rdatahdr_mtime) # merge auto-generated types/classes with meta maps and generate the # corresponding code. generate_typeclasscode('rrtype', rdatahdr_mtime, dict(typecode2txt, **meta_types), 'Type') generate_typeclasscode('rrclass', classdir_mtime, dict(classcode2txt, **meta_classes), 'Class') generate_rrparam('rrparamregistry', rdatahdr_mtime) except: sys.stderr.write('Code generation failed due to exception: %s\n' % sys.exc_info()[1]) exit(1)