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kc3-lang/libevent/event_rpcgen.py

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  • Author : Nick Mathewson
    Date : 2009-07-28 19:41:48
    Hash : a826a758
    Message : Some tweaks to Brodie Thesfield's MSVC patch. svn:r1386

  • event_rpcgen.py
  • #!/usr/bin/env python
    #
    # Copyright (c) 2005 Niels Provos <provos@citi.umich.edu>
    # All rights reserved.
    #
    # Generates marshaling code based on libevent.
    
    # TODO:
    # 1) use optparse to allow the strategy shell to parse options, and
    #    to allow the instantiated factory (for the specific output language)
    #    to parse remaining options
    # 2) move the globals into a class that manages execution (including the
    #    progress outputs that space stderr at the moment)
    # 3) emit other languages
    
    import sys
    import re
    
    _NAME = "event_rpcgen.py"
    _VERSION = "0.1"
    
    # Globals
    line_count = 0
    
    white = re.compile(r'\s+')
    cppcomment = re.compile(r'\/\/.*$')
    nonident = re.compile(r'[^a-zA-Z0-9_]')
    structref = re.compile(r'^struct\[([a-zA-Z_][a-zA-Z0-9_]*)\]$')
    structdef = re.compile(r'^struct +[a-zA-Z_][a-zA-Z0-9_]* *{$')
    
    headerdirect = []
    cppdirect = []
    
    def TranslateList(mylist, mydict):
        return map(lambda x: x % mydict, mylist)
    
    # Exception class for parse errors
    class RpcGenError(Exception):
            def __init__(self, why):
                    self.why = why
            def __str__(self):
                    return str(self.why)
    
    # Holds everything that makes a struct
    class Struct:
        def __init__(self, name):
            self._name = name
            self._entries = []
            self._tags = {}
            print >>sys.stderr, '  Created struct: %s' % name
    
        def AddEntry(self, entry):
            if self._tags.has_key(entry.Tag()):
                raise RpcGenError(
                    'Entry "%s" duplicates tag number %d from "%s" '
                    'around line %d' % (entry.Name(), entry.Tag(),
                                        self._tags[entry.Tag()], line_count))
            self._entries.append(entry)
            self._tags[entry.Tag()] = entry.Name()
            print >>sys.stderr, '    Added entry: %s' % entry.Name()
    
        def Name(self):
            return self._name
    
        def EntryTagName(self, entry):
            """Creates the name inside an enumeration for distinguishing data
            types."""
            name = "%s_%s" % (self._name, entry.Name())
            return name.upper()
    
        def PrintIndented(self, file, ident, code):
            """Takes an array, add indentation to each entry and prints it."""
            for entry in code:
                print >>file, '%s%s' % (ident, entry)
    
    class StructCCode(Struct):
        """ Knows how to generate C code for a struct """
    
        def __init__(self, name):
            Struct.__init__(self, name)
    
        def PrintTags(self, file):
            """Prints the tag definitions for a structure."""
            print >>file, '/* Tag definition for %s */' % self._name
            print >>file, 'enum %s_ {' % self._name.lower()
            for entry in self._entries:
                print >>file, '  %s=%d,' % (self.EntryTagName(entry),
                                            entry.Tag())
            print >>file, '  %s_MAX_TAGS' % (self._name.upper())
            print >>file, '};\n'
    
        def PrintForwardDeclaration(self, file):
            print >>file, 'struct %s;' % self._name
    
        def PrintDeclaration(self, file):
            print >>file, '/* Structure declaration for %s */' % self._name
            print >>file, 'struct %s_access_ {' % self._name
            for entry in self._entries:
                dcl = entry.AssignDeclaration('(*%s_assign)' % entry.Name())
                dcl.extend(
                    entry.GetDeclaration('(*%s_get)' % entry.Name()))
                if entry.Array():
                    dcl.extend(
                        entry.AddDeclaration('(*%s_add)' % entry.Name()))
                self.PrintIndented(file, '  ', dcl)
            print >>file, '};\n'
    
            print >>file, 'struct %s {' % self._name
            print >>file, '  struct %s_access_ *base;\n' % self._name
            for entry in self._entries:
                dcl = entry.Declaration()
                self.PrintIndented(file, '  ', dcl)
            print >>file, ''
            for entry in self._entries:
                print >>file, '  ev_uint8_t %s_set;' % entry.Name()
            print >>file, '};\n'
    
            print >>file, \
    """struct %(name)s *%(name)s_new(void);
    void %(name)s_free(struct %(name)s *);
    void %(name)s_clear(struct %(name)s *);
    void %(name)s_marshal(struct evbuffer *, const struct %(name)s *);
    int %(name)s_unmarshal(struct %(name)s *, struct evbuffer *);
    int %(name)s_complete(struct %(name)s *);
    void evtag_marshal_%(name)s(struct evbuffer *, ev_uint32_t,
        const struct %(name)s *);
    int evtag_unmarshal_%(name)s(struct evbuffer *, ev_uint32_t,
        struct %(name)s *);""" % { 'name' : self._name }
    
    
            # Write a setting function of every variable
            for entry in self._entries:
                self.PrintIndented(file, '', entry.AssignDeclaration(
                    entry.AssignFuncName()))
                self.PrintIndented(file, '', entry.GetDeclaration(
                    entry.GetFuncName()))
                if entry.Array():
                    self.PrintIndented(file, '', entry.AddDeclaration(
                        entry.AddFuncName()))
    
            print >>file, '/* --- %s done --- */\n' % self._name
    
        def PrintCode(self, file):
            print >>file, ('/*\n'
                           ' * Implementation of %s\n'
                           ' */\n') % self._name
    
            print >>file, \
                  'static struct %(name)s_access_ __%(name)s_base = {' % \
                  { 'name' : self._name }
            for entry in self._entries:
                self.PrintIndented(file, '  ', entry.CodeBase())
            print >>file, '};\n'
    
            # Creation
            print >>file, (
                'struct %(name)s *\n'
                '%(name)s_new(void)\n'
                '{\n'
                '  struct %(name)s *tmp;\n'
                '  if ((tmp = malloc(sizeof(struct %(name)s))) == NULL) {\n'
                '    event_warn("%%s: malloc", __func__);\n'
                '    return (NULL);\n'
                '  }\n'
                '  tmp->base = &__%(name)s_base;\n') % { 'name' : self._name }
    
            for entry in self._entries:
                self.PrintIndented(file, '  ', entry.CodeInitialize('tmp'))
                print >>file, '  tmp->%s_set = 0;\n' % entry.Name()
    
            print >>file, (
                '  return (tmp);\n'
                '}\n')
    
            # Adding
            for entry in self._entries:
                if entry.Array():
                    self.PrintIndented(file, '', entry.CodeAdd())
                print >>file, ''
    
            # Assigning
            for entry in self._entries:
                self.PrintIndented(file, '', entry.CodeAssign())
                print >>file, ''
    
            # Getting
            for entry in self._entries:
                self.PrintIndented(file, '', entry.CodeGet())
                print >>file, ''
    
            # Clearing
            print >>file, ( 'void\n'
                            '%(name)s_clear(struct %(name)s *tmp)\n'
                            '{'
                            ) % { 'name' : self._name }
            for entry in self._entries:
                self.PrintIndented(file, '  ', entry.CodeClear('tmp'))
    
            print >>file, '}\n'
    
            # Freeing
            print >>file, ( 'void\n'
                            '%(name)s_free(struct %(name)s *tmp)\n'
                            '{'
                            ) % { 'name' : self._name }
    
            for entry in self._entries:
                self.PrintIndented(file, '  ', entry.CodeFree('tmp'))
    
            print >>file, ('  free(tmp);\n'
                           '}\n')
    
            # Marshaling
            print >>file, ('void\n'
                           '%(name)s_marshal(struct evbuffer *evbuf, '
                           'const struct %(name)s *tmp)'
                           '{') % { 'name' : self._name }
            for entry in self._entries:
                indent = '  '
                # Optional entries do not have to be set
                if entry.Optional():
                    indent += '  '
                    print >>file, '  if (tmp->%s_set) {' % entry.Name()
                self.PrintIndented(
                    file, indent,
                    entry.CodeMarshal('evbuf', self.EntryTagName(entry),
                                      entry.GetVarName('tmp'),
                                      entry.GetVarLen('tmp')))
                if entry.Optional():
                    print >>file, '  }'
    
            print >>file, '}\n'
    
            # Unmarshaling
            print >>file, ('int\n'
                           '%(name)s_unmarshal(struct %(name)s *tmp, '
                           ' struct evbuffer *evbuf)\n'
                           '{\n'
                           '  ev_uint32_t tag;\n'
                           '  while (evbuffer_get_length(evbuf) > 0) {\n'
                           '    if (evtag_peek(evbuf, &tag) == -1)\n'
                           '      return (-1);\n'
                           '    switch (tag) {\n'
                           ) % { 'name' : self._name }
            for entry in self._entries:
                print >>file, '      case %s:\n' % self.EntryTagName(entry)
                if not entry.Array():
                    print >>file, (
                        '        if (tmp->%s_set)\n'
                        '          return (-1);'
                        ) % (entry.Name())
    
                self.PrintIndented(
                    file, '        ',
                    entry.CodeUnmarshal('evbuf',
                                        self.EntryTagName(entry),
                                        entry.GetVarName('tmp'),
                                        entry.GetVarLen('tmp')))
    
                print >>file, ( '        tmp->%s_set = 1;\n' % entry.Name() +
                                '        break;\n' )
            print >>file, ( '      default:\n'
                            '        return -1;\n'
                            '    }\n'
                            '  }\n' )
            # Check if it was decoded completely
            print >>file, ( '  if (%(name)s_complete(tmp) == -1)\n'
                            '    return (-1);'
                            ) % { 'name' : self._name }
    
            # Successfully decoded
            print >>file, ( '  return (0);\n'
                            '}\n')
    
            # Checking if a structure has all the required data
            print >>file, (
                'int\n'
                '%(name)s_complete(struct %(name)s *msg)\n'
                '{' ) % { 'name' : self._name }
            for entry in self._entries:
                if not entry.Optional():
                    code = [
                        'if (!msg->%(name)s_set)',
                        '  return (-1);' ]
                    code = TranslateList(code, entry.GetTranslation())
                    self.PrintIndented(
                        file, '  ', code)
    
                self.PrintIndented(
                    file, '  ',
                    entry.CodeComplete('msg', entry.GetVarName('msg')))
            print >>file, (
                '  return (0);\n'
                '}\n' )
    
            # Complete message unmarshaling
            print >>file, (
                'int\n'
                'evtag_unmarshal_%(name)s(struct evbuffer *evbuf, '
                'ev_uint32_t need_tag, struct %(name)s *msg)\n'
                '{\n'
                '  ev_uint32_t tag;\n'
                '  int res = -1;\n'
                '\n'
                '  struct evbuffer *tmp = evbuffer_new();\n'
                '\n'
                '  if (evtag_unmarshal(evbuf, &tag, tmp) == -1'
                ' || tag != need_tag)\n'
                '    goto error;\n'
                '\n'
                '  if (%(name)s_unmarshal(msg, tmp) == -1)\n'
                '    goto error;\n'
                '\n'
                '  res = 0;\n'
                '\n'
                ' error:\n'
                '  evbuffer_free(tmp);\n'
                '  return (res);\n'
                '}\n' ) % { 'name' : self._name }
    
            # Complete message marshaling
            print >>file, (
                'void\n'
                'evtag_marshal_%(name)s(struct evbuffer *evbuf, ev_uint32_t tag, '
                'const struct %(name)s *msg)\n'
                '{\n'
                '  struct evbuffer *_buf = evbuffer_new();\n'
                '  assert(_buf != NULL);\n'
                '  %(name)s_marshal(_buf, msg);\n'
                '  evtag_marshal_buffer(evbuf, tag, _buf);\n '
                '  evbuffer_free(_buf);\n'
                '}\n' ) % { 'name' : self._name }
    
    class Entry:
        def __init__(self, type, name, tag):
            self._type = type
            self._name = name
            self._tag = int(tag)
            self._ctype = type
            self._optional = 0
            self._can_be_array = 0
            self._array = 0
            self._line_count = -1
            self._struct = None
            self._refname = None
    
            self._optpointer = True
            self._optaddarg = True
    
        def GetInitializer(self):
            assert 0, "Entry does not provide initializer"
    
        def SetStruct(self, struct):
            self._struct = struct
    
        def LineCount(self):
            assert self._line_count != -1
            return self._line_count
    
        def SetLineCount(self, number):
            self._line_count = number
    
        def Array(self):
            return self._array
    
        def Optional(self):
            return self._optional
    
        def Tag(self):
            return self._tag
    
        def Name(self):
            return self._name
    
        def Type(self):
            return self._type
    
        def MakeArray(self, yes=1):
            self._array = yes
    
        def MakeOptional(self):
            self._optional = 1
    
        def Verify(self):
            if self.Array() and not self._can_be_array:
                raise RpcGenError(
                    'Entry "%s" cannot be created as an array '
                    'around line %d' % (self._name, self.LineCount()))
            if not self._struct:
                raise RpcGenError(
                    'Entry "%s" does not know which struct it belongs to '
                    'around line %d' % (self._name, self.LineCount()))
            if self._optional and self._array:
                raise RpcGenError(
                    'Entry "%s" has illegal combination of optional and array '
                    'around line %d' % (self._name, self.LineCount()))
    
        def GetTranslation(self, extradict = {}):
            mapping = {
                "parent_name" : self._struct.Name(),
                "name" : self._name,
                "ctype" : self._ctype,
                "refname" : self._refname,
                "optpointer" : self._optpointer and "*" or "",
                "optreference" : self._optpointer and "&" or "",
                "optaddarg" :
                self._optaddarg and ", const %s value" % self._ctype or ""
                }
            for (k, v) in extradict.items():
                mapping[k] = v
    
            return mapping
    
        def GetVarName(self, var):
            return '%(var)s->%(name)s_data' % self.GetTranslation({ 'var' : var })
    
        def GetVarLen(self, var):
            return 'sizeof(%s)' % self._ctype
    
        def GetFuncName(self):
            return '%s_%s_get' % (self._struct.Name(), self._name)
    
        def GetDeclaration(self, funcname):
            code = [ 'int %s(struct %s *, %s *);' % (
                funcname, self._struct.Name(), self._ctype ) ]
            return code
    
        def CodeGet(self):
            code = (
                'int',
                '%(parent_name)s_%(name)s_get(struct %(parent_name)s *msg, '
                '%(ctype)s *value)',
                '{',
                '  if (msg->%(name)s_set != 1)',
                '    return (-1);',
                '  *value = msg->%(name)s_data;',
                '  return (0);',
                '}' )
            code = '\n'.join(code)
            code = code % self.GetTranslation()
            return code.split('\n')
    
        def AssignFuncName(self):
            return '%s_%s_assign' % (self._struct.Name(), self._name)
    
        def AddFuncName(self):
            return '%s_%s_add' % (self._struct.Name(), self._name)
    
        def AssignDeclaration(self, funcname):
            code = [ 'int %s(struct %s *, const %s);' % (
                funcname, self._struct.Name(), self._ctype ) ]
            return code
    
        def CodeAssign(self):
            code = [ 'int',
                     '%(parent_name)s_%(name)s_assign(struct %(parent_name)s *msg,'
                     ' const %(ctype)s value)',
                     '{',
                     '  msg->%(name)s_set = 1;',
                     '  msg->%(name)s_data = value;',
                     '  return (0);',
                     '}' ]
            code = '\n'.join(code)
            code = code % self.GetTranslation()
            return code.split('\n')
    
        def CodeClear(self, structname):
            code = [ '%s->%s_set = 0;' % (structname, self.Name()) ]
    
            return code
    
        def CodeComplete(self, structname, var_name):
            return []
    
        def CodeFree(self, name):
            return []
    
        def CodeBase(self):
            code = [
                '%(parent_name)s_%(name)s_assign,',
                '%(parent_name)s_%(name)s_get,'
                ]
            if self.Array():
                code.append('%(parent_name)s_%(name)s_add,')
    
            code = '\n'.join(code)
            code = code % self.GetTranslation()
            return code.split('\n')
    
    class EntryBytes(Entry):
        def __init__(self, type, name, tag, length):
            # Init base class
            Entry.__init__(self, type, name, tag)
    
            self._length = length
            self._ctype = 'ev_uint8_t'
    
        def GetInitializer(self):
            return "NULL"
    
        def GetVarLen(self, var):
            return '(%s)' % self._length
    
        def CodeArrayAdd(self, varname, value):
            # XXX: copy here
            return [ '%(varname)s = NULL;' % { 'varname' : varname } ]
    
        def GetDeclaration(self, funcname):
            code = [ 'int %s(struct %s *, %s **);' % (
                funcname, self._struct.Name(), self._ctype ) ]
            return code
    
        def AssignDeclaration(self, funcname):
            code = [ 'int %s(struct %s *, const %s *);' % (
                funcname, self._struct.Name(), self._ctype ) ]
            return code
    
        def Declaration(self):
            dcl  = ['ev_uint8_t %s_data[%s];' % (self._name, self._length)]
    
            return dcl
    
        def CodeGet(self):
            name = self._name
            code = [ 'int',
                     '%s_%s_get(struct %s *msg, %s **value)' % (
                self._struct.Name(), name,
                self._struct.Name(), self._ctype),
                     '{',
                     '  if (msg->%s_set != 1)' % name,
                     '    return (-1);',
                     '  *value = msg->%s_data;' % name,
                     '  return (0);',
                     '}' ]
            return code
    
        def CodeAssign(self):
            name = self._name
            code = [ 'int',
                     '%s_%s_assign(struct %s *msg, const %s *value)' % (
                self._struct.Name(), name,
                self._struct.Name(), self._ctype),
                     '{',
                     '  msg->%s_set = 1;' % name,
                     '  memcpy(msg->%s_data, value, %s);' % (
                name, self._length),
                     '  return (0);',
                     '}' ]
            return code
    
        def CodeUnmarshal(self, buf, tag_name, var_name, var_len):
            code = [  'if (evtag_unmarshal_fixed(%(buf)s, %(tag)s, '
                      '%(var)s, %(varlen)s) == -1) {',
                      '  event_warnx("%%s: failed to unmarshal %(name)s", __func__);',
                      '  return (-1);',
                      '}'
                      ]
            return TranslateList(code,
                                 self.GetTranslation({
                'var' : var_name,
                'varlen' : var_len,
                'buf' : buf,
                'tag' : tag_name }))
    
        def CodeMarshal(self, buf, tag_name, var_name, var_len):
            code = ['evtag_marshal(%s, %s, %s, %s);' % (
                buf, tag_name, var_name, var_len)]
            return code
    
        def CodeClear(self, structname):
            code = [ '%s->%s_set = 0;' % (structname, self.Name()),
                     'memset(%s->%s_data, 0, sizeof(%s->%s_data));' % (
                structname, self._name, structname, self._name)]
    
            return code
    
        def CodeInitialize(self, name):
            code  = ['memset(%s->%s_data, 0, sizeof(%s->%s_data));' % (
                name, self._name, name, self._name)]
            return code
    
        def Verify(self):
            if not self._length:
                raise RpcGenError(
                    'Entry "%s" needs a length '
                    'around line %d' % (self._name, self.LineCount()))
    
            Entry.Verify(self)
    
    class EntryInt(Entry):
        def __init__(self, type, name, tag, bits=32):
            # Init base class
            Entry.__init__(self, type, name, tag)
    
            self._can_be_array = 1
            if bits == 32:
                self._ctype = 'ev_uint32_t'
                self._marshal_type = 'int'
            if bits == 64:
                self._ctype = 'ev_uint64_t'
                self._marshal_type = 'int64'
    
        def GetInitializer(self):
            return "0"
    
        def CodeArrayFree(self, var):
            return []
    
        def CodeArrayAssign(self, varname, srcvar):
            return [ '%(varname)s = %(srcvar)s;' % { 'varname' : varname,
                                                    'srcvar' : srcvar } ]
    
        def CodeArrayAdd(self, varname, value):
            """Returns a new entry of this type."""
            return [ '%(varname)s = %(value)s;' % { 'varname' : varname,
                                                  'value' : value } ]
    
        def CodeUnmarshal(self, buf, tag_name, var_name, var_len):
            code = [
                'if (evtag_unmarshal_%(ma)s(%(buf)s, %(tag)s, &%(var)s) == -1) {',
                '  event_warnx("%%s: failed to unmarshal %(name)s", __func__);',
                '  return (-1);',
                '}' ]
            code = '\n'.join(code) % self.GetTranslation({
                'ma'  : self._marshal_type,
                'buf' : buf,
                'tag' : tag_name,
                'var' : var_name })
            return code.split('\n')
    
        def CodeMarshal(self, buf, tag_name, var_name, var_len):
            code = [
                'evtag_marshal_%s(%s, %s, %s);' % (
                self._marshal_type, buf, tag_name, var_name)]
            return code
    
        def Declaration(self):
            dcl  = ['%s %s_data;' % (self._ctype, self._name)]
    
            return dcl
    
        def CodeInitialize(self, name):
            code = ['%s->%s_data = 0;' % (name, self._name)]
            return code
    
    class EntryString(Entry):
        def __init__(self, type, name, tag):
            # Init base class
            Entry.__init__(self, type, name, tag)
    
            self._can_be_array = 1
            self._ctype = 'char *'
    
        def GetInitializer(self):
            return "NULL"
    
        def CodeArrayFree(self, varname):
            code = [
                'if (%(var)s != NULL) free(%(var)s);' ]
    
            return TranslateList(code, { 'var' : varname })
    
        def CodeArrayAssign(self, varname, srcvar):
            code = [
                'if (%(var)s != NULL)',
                '  free(%(var)s);',
                '%(var)s = strdup(%(srcvar)s);',
                'if (%(var)s == NULL) {',
                '  event_warnx("%%s: strdup", __func__);',
                '  return (-1);',
                '}' ]
    
            return TranslateList(code, { 'var' : varname,
                                         'srcvar' : srcvar })
    
        def CodeArrayAdd(self, varname, value):
            code = [
                'if (%(value)s != NULL) {',
                '  %(var)s = strdup(%(value)s);',
                '  if (%(var)s == NULL) {',
                '    goto error;',
                '  }',
                '} else {',
                '  %(var)s = NULL;',
                '}' ]
    
            return TranslateList(code, { 'var' : varname,
                                         'value' : value })
    
        def GetVarLen(self, var):
            return 'strlen(%s)' % self.GetVarName(var)
    
        def CodeMakeInitalize(self, varname):
            return '%(varname)s = NULL;' % { 'varname' : varname }
    
        def CodeAssign(self):
            name = self._name
            code = """int
    %(parent_name)s_%(name)s_assign(struct %(parent_name)s *msg,
        const %(ctype)s value)
    {
      if (msg->%(name)s_data != NULL)
        free(msg->%(name)s_data);
      if ((msg->%(name)s_data = strdup(value)) == NULL)
        return (-1);
      msg->%(name)s_set = 1;
      return (0);
    }""" % self.GetTranslation()
    
            return code.split('\n')
    
        def CodeUnmarshal(self, buf, tag_name, var_name, var_len):
            code = ['if (evtag_unmarshal_string(%(buf)s, %(tag)s, &%(var)s) == -1) {',
                    '  event_warnx("%%s: failed to unmarshal %(name)s", __func__);',
                    '  return (-1);',
                    '}'
                    ]
            code = '\n'.join(code) % self.GetTranslation({
                'buf' : buf,
                'tag' : tag_name,
                'var' : var_name })
            return code.split('\n')
    
        def CodeMarshal(self, buf, tag_name, var_name, var_len):
            code = ['evtag_marshal_string(%s, %s, %s);' % (
                buf, tag_name, var_name)]
            return code
    
        def CodeClear(self, structname):
            code = [ 'if (%s->%s_set == 1) {' % (structname, self.Name()),
                     '  free(%s->%s_data);' % (structname, self.Name()),
                     '  %s->%s_data = NULL;' % (structname, self.Name()),
                     '  %s->%s_set = 0;' % (structname, self.Name()),
                     '}'
                     ]
    
            return code
    
        def CodeInitialize(self, name):
            code  = ['%s->%s_data = NULL;' % (name, self._name)]
            return code
    
        def CodeFree(self, name):
            code  = ['if (%s->%s_data != NULL)' % (name, self._name),
                     '    free (%s->%s_data);' % (name, self._name)]
    
            return code
    
        def Declaration(self):
            dcl  = ['char *%s_data;' % self._name]
    
            return dcl
    
    class EntryStruct(Entry):
        def __init__(self, type, name, tag, refname):
            # Init base class
            Entry.__init__(self, type, name, tag)
    
            self._optpointer = False
            self._can_be_array = 1
            self._refname = refname
            self._ctype = 'struct %s*' % refname
            self._optaddarg = False
    
        def GetInitializer(self):
            return "NULL"
    
        def GetVarLen(self, var):
            return '-1'
    
        def CodeArrayAdd(self, varname, value):
            code = [
                '%(varname)s = %(refname)s_new();',
                'if (%(varname)s == NULL)',
                '  goto error;' ]
    
            return TranslateList(code, self.GetTranslation({ 'varname' : varname }))
    
        def CodeArrayFree(self, var):
            code = [ '%(refname)s_free(%(var)s);' % self.GetTranslation(
                { 'var' : var }) ]
            return code
    
        def CodeArrayAssign(self, var, srcvar):
            code = [
                'int had_error = 0;',
                'struct evbuffer *tmp = NULL;',
                '%(refname)s_clear(%(var)s);',
                'if ((tmp = evbuffer_new()) == NULL) {',
                '  event_warn("%%s: evbuffer_new()", __func__);',
                '  had_error = 1;',
                '  goto done;',
                '}',
                '%(refname)s_marshal(tmp, %(srcvar)s);',
                'if (%(refname)s_unmarshal(%(var)s, tmp) == -1) {',
                '  event_warnx("%%s: %(refname)s_unmarshal", __func__);',
                '  had_error = 1;',
                '  goto done;',
                '}',
                'done:'
                'if (tmp != NULL)',
                '  evbuffer_free(tmp);',
                'if (had_error) {',
                '  %(refname)s_clear(%(var)s);',
                '  return (-1);',
                '}' ]
    
            return TranslateList(code, self.GetTranslation({
                'var' : var,
                'srcvar' : srcvar}))
    
        def CodeGet(self):
            name = self._name
            code = [ 'int',
                     '%s_%s_get(struct %s *msg, %s *value)' % (
                self._struct.Name(), name,
                self._struct.Name(), self._ctype),
                     '{',
                     '  if (msg->%s_set != 1) {' % name,
                     '    msg->%s_data = %s_new();' % (name, self._refname),
                     '    if (msg->%s_data == NULL)' % name,
                     '      return (-1);',
                     '    msg->%s_set = 1;' % name,
                     '  }',
                     '  *value = msg->%s_data;' % name,
                     '  return (0);',
                     '}' ]
            return code
    
        def CodeAssign(self):
            name = self._name
            code = """int
    %(parent_name)s_%(name)s_assign(struct %(parent_name)s *msg,
        const %(ctype)s value)
    {
       struct evbuffer *tmp = NULL;
       if (msg->%(name)s_set) {
         %(refname)s_clear(msg->%(name)s_data);
         msg->%(name)s_set = 0;
       } else {
         msg->%(name)s_data = %(refname)s_new();
         if (msg->%(name)s_data == NULL) {
           event_warn("%%s: %(refname)s_new()", __func__);
           goto error;
         }
       }
       if ((tmp = evbuffer_new()) == NULL) {
         event_warn("%%s: evbuffer_new()", __func__);
         goto error;
       }
       %(refname)s_marshal(tmp, value);
       if (%(refname)s_unmarshal(msg->%(name)s_data, tmp) == -1) {
         event_warnx("%%s: %(refname)s_unmarshal", __func__);
         goto error;
       }
       msg->%(name)s_set = 1;
       evbuffer_free(tmp);
       return (0);
     error:
       if (tmp != NULL)
         evbuffer_free(tmp);
       if (msg->%(name)s_data != NULL) {
         %(refname)s_free(msg->%(name)s_data);
         msg->%(name)s_data = NULL;
       }
       return (-1);
    }""" % self.GetTranslation()
            return code.split('\n')
    
        def CodeComplete(self, structname, var_name):
            code = [ 'if (%(structname)s->%(name)s_set && '
                     '%(refname)s_complete(%(var)s) == -1)',
                     '  return (-1);' ]
    
            return TranslateList(code, self.GetTranslation({
                'structname' : structname,
                'var' : var_name }))
    
        def CodeUnmarshal(self, buf, tag_name, var_name, var_len):
            code = ['%(var)s = %(refname)s_new();',
                    'if (%(var)s == NULL)',
                    '  return (-1);',
                    'if (evtag_unmarshal_%(refname)s(%(buf)s, %(tag)s, '
                    '%(var)s) == -1) {',
                      '  event_warnx("%%s: failed to unmarshal %(name)s", __func__);',
                    '  return (-1);',
                    '}'
                    ]
            code = '\n'.join(code) % self.GetTranslation({
                'buf' : buf,
                'tag' : tag_name,
                'var' : var_name })
            return code.split('\n')
    
        def CodeMarshal(self, buf, tag_name, var_name, var_len):
            code = ['evtag_marshal_%s(%s, %s, %s);' % (
                self._refname, buf, tag_name, var_name)]
            return code
    
        def CodeClear(self, structname):
            code = [ 'if (%s->%s_set == 1) {' % (structname, self.Name()),
                     '  %s_free(%s->%s_data);' % (
                self._refname, structname, self.Name()),
                     '  %s->%s_data = NULL;' % (structname, self.Name()),
                     '  %s->%s_set = 0;' % (structname, self.Name()),
                     '}'
                     ]
    
            return code
    
        def CodeInitialize(self, name):
            code  = ['%s->%s_data = NULL;' % (name, self._name)]
            return code
    
        def CodeFree(self, name):
            code  = ['if (%s->%s_data != NULL)' % (name, self._name),
                     '    %s_free(%s->%s_data);' % (
                self._refname, name, self._name)]
    
            return code
    
        def Declaration(self):
            dcl  = ['%s %s_data;' % (self._ctype, self._name)]
    
            return dcl
    
    class EntryVarBytes(Entry):
        def __init__(self, type, name, tag):
            # Init base class
            Entry.__init__(self, type, name, tag)
    
            self._ctype = 'ev_uint8_t *'
    
        def GetInitializer(self):
            return "NULL"
    
        def GetVarLen(self, var):
            return '%(var)s->%(name)s_length' % self.GetTranslation({ 'var' : var })
    
        def CodeArrayAdd(self, varname, value):
            # xxx: copy
            return [ '%(varname)s = NULL;' % { 'varname' : varname } ]
    
        def GetDeclaration(self, funcname):
            code = [ 'int %s(struct %s *, %s *, ev_uint32_t *);' % (
                funcname, self._struct.Name(), self._ctype ) ]
            return code
    
        def AssignDeclaration(self, funcname):
            code = [ 'int %s(struct %s *, const %s, ev_uint32_t);' % (
                funcname, self._struct.Name(), self._ctype ) ]
            return code
    
        def CodeAssign(self):
            name = self._name
            code = [ 'int',
                     '%s_%s_assign(struct %s *msg, '
                     'const %s value, ev_uint32_t len)' % (
                self._struct.Name(), name,
                self._struct.Name(), self._ctype),
                     '{',
                     '  if (msg->%s_data != NULL)' % name,
                     '    free (msg->%s_data);' % name,
                     '  msg->%s_data = malloc(len);' % name,
                     '  if (msg->%s_data == NULL)' % name,
                     '    return (-1);',
                     '  msg->%s_set = 1;' % name,
                     '  msg->%s_length = len;' % name,
                     '  memcpy(msg->%s_data, value, len);' % name,
                     '  return (0);',
                     '}' ]
            return code
    
        def CodeGet(self):
            name = self._name
            code = [ 'int',
                     '%s_%s_get(struct %s *msg, %s *value, ev_uint32_t *plen)' % (
                self._struct.Name(), name,
                self._struct.Name(), self._ctype),
                     '{',
                     '  if (msg->%s_set != 1)' % name,
                     '    return (-1);',
                     '  *value = msg->%s_data;' % name,
                     '  *plen = msg->%s_length;' % name,
                     '  return (0);',
                     '}' ]
            return code
    
        def CodeUnmarshal(self, buf, tag_name, var_name, var_len):
            code = ['if (evtag_payload_length(%(buf)s, &%(varlen)s) == -1)',
                    '  return (-1);',
                    # We do not want DoS opportunities
                    'if (%(varlen)s > evbuffer_get_length(%(buf)s))',
                    '  return (-1);',
                    'if ((%(var)s = malloc(%(varlen)s)) == NULL)',
                    '  return (-1);',
                    'if (evtag_unmarshal_fixed(%(buf)s, %(tag)s, %(var)s, '
                    '%(varlen)s) == -1) {',
                    '  event_warnx("%%s: failed to unmarshal %(name)s", __func__);',
                    '  return (-1);',
                    '}'
                    ]
            code = '\n'.join(code) % self.GetTranslation({
                'buf' : buf,
                'tag' : tag_name,
                'var' : var_name,
                'varlen' : var_len })
            return code.split('\n')
    
        def CodeMarshal(self, buf, tag_name, var_name, var_len):
            code = ['evtag_marshal(%s, %s, %s, %s);' % (
                buf, tag_name, var_name, var_len)]
            return code
    
        def CodeClear(self, structname):
            code = [ 'if (%s->%s_set == 1) {' % (structname, self.Name()),
                     '  free (%s->%s_data);' % (structname, self.Name()),
                     '  %s->%s_data = NULL;' % (structname, self.Name()),
                     '  %s->%s_length = 0;' % (structname, self.Name()),
                     '  %s->%s_set = 0;' % (structname, self.Name()),
                     '}'
                     ]
    
            return code
    
        def CodeInitialize(self, name):
            code  = ['%s->%s_data = NULL;' % (name, self._name),
                     '%s->%s_length = 0;' % (name, self._name) ]
            return code
    
        def CodeFree(self, name):
            code  = ['if (%s->%s_data != NULL)' % (name, self._name),
                     '    free(%s->%s_data);' % (name, self._name)]
    
            return code
    
        def Declaration(self):
            dcl  = ['ev_uint8_t *%s_data;' % self._name,
                    'ev_uint32_t %s_length;' % self._name]
    
            return dcl
    
    class EntryArray(Entry):
        def __init__(self, entry):
            # Init base class
            Entry.__init__(self, entry._type, entry._name, entry._tag)
    
            self._entry = entry
            self._refname = entry._refname
            self._ctype = self._entry._ctype
            self._optional = True
            self._optpointer = self._entry._optpointer
            self._optaddarg = self._entry._optaddarg
    
            # provide a new function for accessing the variable name
            def GetVarName(var_name):
                return '%(var)s->%(name)s_data[%(index)s]' % \
                       self._entry.GetTranslation({'var' : var_name,
                                                   'index' : self._index})
            self._entry.GetVarName = GetVarName
    
        def GetInitializer(self):
            return "NULL"
    
        def GetVarName(self, var_name):
            return var_name
    
        def GetVarLen(self, var_name):
            return '-1'
    
        def GetDeclaration(self, funcname):
            """Allows direct access to elements of the array."""
            code = [
                'int %(funcname)s(struct %(parent_name)s *, int, %(ctype)s *);' %
                self.GetTranslation({ 'funcname' : funcname }) ]
            return code
    
        def AssignDeclaration(self, funcname):
            code = [ 'int %s(struct %s *, int, const %s);' % (
                funcname, self._struct.Name(), self._ctype ) ]
            return code
    
        def AddDeclaration(self, funcname):
            code = [
                '%(ctype)s %(optpointer)s '
                '%(funcname)s(struct %(parent_name)s *msg%(optaddarg)s);' % \
                self.GetTranslation({ 'funcname' : funcname }) ]
            return code
    
        def CodeGet(self):
            code = """int
    %(parent_name)s_%(name)s_get(struct %(parent_name)s *msg, int offset,
        %(ctype)s *value)
    {
      if (!msg->%(name)s_set || offset < 0 || offset >= msg->%(name)s_length)
        return (-1);
      *value = msg->%(name)s_data[offset];
      return (0);
    }""" % self.GetTranslation()
    
            return code.split('\n')
    
        def CodeAssign(self):
            code = [
                'int',
                '%(parent_name)s_%(name)s_assign(struct %(parent_name)s *msg, int off,',
                '    const %(ctype)s value)',
                '{',
                '  if (!msg->%(name)s_set || off < 0 || off >= msg->%(name)s_length)',
                '    return (-1);\n',
                '  {' ]
            code = TranslateList(code, self.GetTranslation())
    
            codearrayassign = self._entry.CodeArrayAssign(
                'msg->%(name)s_data[off]' % self.GetTranslation(), 'value')
            code += map(lambda x: '    ' + x, codearrayassign)
    
            code += TranslateList([
                '  }',
                '  return (0);',
                '}' ], self.GetTranslation())
    
            return code
    
        def CodeAdd(self):
            codearrayadd = self._entry.CodeArrayAdd(
                'msg->%(name)s_data[msg->%(name)s_length - 1]' % self.GetTranslation(),
                'value')
            code = [
                '%(ctype)s %(optpointer)s',
                '%(parent_name)s_%(name)s_add('
                'struct %(parent_name)s *msg%(optaddarg)s)',
                '{',
                '  if (++msg->%(name)s_length >= msg->%(name)s_num_allocated) {',
                '    int tobe_allocated = msg->%(name)s_num_allocated;',
                '    %(ctype)s* new_data = NULL;',
                '    tobe_allocated = !tobe_allocated ? 1 : tobe_allocated << 1;',
                '    new_data = (%(ctype)s*) realloc(msg->%(name)s_data,',
                '        tobe_allocated * sizeof(%(ctype)s));',
                '    if (new_data == NULL)',
                '      goto error;',
                '    msg->%(name)s_data = new_data;',
                '    msg->%(name)s_num_allocated = tobe_allocated;',
                '  }' ]
    
            code = TranslateList(code, self.GetTranslation())
    
            code += map(lambda x: '  ' + x, codearrayadd)
    
            code += TranslateList([
                '  msg->%(name)s_set = 1;',
                '  return %(optreference)s(msg->%(name)s_data['
                'msg->%(name)s_length - 1]);',
                'error:',
                '  --msg->%(name)s_length;',
                '  return (NULL);',
                '}' ], self.GetTranslation())
    
            return code
    
        def CodeComplete(self, structname, var_name):
            self._index = 'i'
            tmp = self._entry.CodeComplete(structname, self._entry.GetVarName(var_name))
            # skip the whole loop if there is nothing to check
            if not tmp:
                return []
    
            translate = self.GetTranslation({ 'structname' : structname })
            code = [
                '{',
                '  int i;',
                '  for (i = 0; i < %(structname)s->%(name)s_length; ++i) {' ]
    
            code = TranslateList(code, translate)
    
            code += map(lambda x: '    ' + x, tmp)
    
            code += [
                '  }',
                '}' ]
    
            return code
    
        def CodeUnmarshal(self, buf, tag_name, var_name, var_len):
            translate = self.GetTranslation({ 'var' : var_name,
                                              'buf' : buf,
                                              'tag' : tag_name,
                                              'init' : self._entry.GetInitializer()})
            if self._optaddarg:
                code = [
                    'if (%(parent_name)s_%(name)s_add(%(var)s, %(init)s) == NULL)',
                    '  return (-1);' ]
            else:
                code = [
                    'if (%(parent_name)s_%(name)s_add(%(var)s) == NULL)',
                    '  return (-1);' ]
    
            # the unmarshal code directly returns
            code += [ '--%(var)s->%(name)s_length;' % translate ]
            code = TranslateList(code, translate)
    
            self._index = '%(var)s->%(name)s_length' % translate
            code += self._entry.CodeUnmarshal(buf, tag_name,
                                            self._entry.GetVarName(var_name),
                                            self._entry.GetVarLen(var_name))
    
            code += [ '++%(var)s->%(name)s_length;' % translate ]
    
            return code
    
        def CodeMarshal(self, buf, tag_name, var_name, var_len):
            code = ['{',
                    '  int i;',
                    '  for (i = 0; i < %(var)s->%(name)s_length; ++i) {' ]
    
            self._index = 'i'
            code += self._entry.CodeMarshal(buf, tag_name,
                                            self._entry.GetVarName(var_name),
                                            self._entry.GetVarLen(var_name))
            code += ['  }',
                     '}'
                     ]
    
            code = "\n".join(code) % self.GetTranslation({ 'var' : var_name })
    
            return code.split('\n')
    
        def CodeClear(self, structname):
            translate = self.GetTranslation({ 'structname' : structname })
            codearrayfree = self._entry.CodeArrayFree(
                '%(structname)s->%(name)s_data[i]' % self.GetTranslation(
                { 'structname' : structname } ))
    
            code = [ 'if (%(structname)s->%(name)s_set == 1) {' ]
    
            if codearrayfree:
                code += [
                    '  int i;',
                    '  for (i = 0; i < %(structname)s->%(name)s_length; ++i) {' ]
    
            code = TranslateList(code, translate)
    
            if codearrayfree:
                code += map(lambda x: '    ' + x, codearrayfree)
                code += [
                    '  }' ]
    
            code += TranslateList([
                     '  free(%(structname)s->%(name)s_data);',
                     '  %(structname)s->%(name)s_data = NULL;',
                     '  %(structname)s->%(name)s_set = 0;',
                     '  %(structname)s->%(name)s_length = 0;',
                     '  %(structname)s->%(name)s_num_allocated = 0;',
                     '}'
                     ], translate)
    
            return code
    
        def CodeInitialize(self, name):
            code  = ['%s->%s_data = NULL;' % (name, self._name),
                     '%s->%s_length = 0;' % (name, self._name),
                     '%s->%s_num_allocated = 0;' % (name, self._name)]
            return code
    
        def CodeFree(self, structname):
            code = self.CodeClear(structname);
    
            code += TranslateList([
                'free(%(structname)s->%(name)s_data);' ],
                                  self.GetTranslation({'structname' : structname }))
    
            return code
    
        def Declaration(self):
            dcl  = ['%s *%s_data;' % (self._ctype, self._name),
                    'int %s_length;' % self._name,
                    'int %s_num_allocated;' % self._name ]
    
            return dcl
    
    def NormalizeLine(line):
        global white
        global cppcomment
    
        line = cppcomment.sub('', line)
        line = line.strip()
        line = white.sub(' ', line)
    
        return line
    
    def ProcessOneEntry(factory, newstruct, entry):
        optional = 0
        array = 0
        entry_type = ''
        name = ''
        tag = ''
        tag_set = None
        separator = ''
        fixed_length = ''
    
        tokens = entry.split(' ')
        while tokens:
            token = tokens[0]
            tokens = tokens[1:]
    
            if not entry_type:
                if not optional and token == 'optional':
                    optional = 1
                    continue
    
                if not array and token == 'array':
                    array = 1
                    continue
    
            if not entry_type:
                entry_type = token
                continue
    
            if not name:
                res = re.match(r'^([^\[\]]+)(\[.*\])?$', token)
                if not res:
                     raise RpcGenError(
                         'Cannot parse name: \"%s\" '
                         'around line %d' % (entry, line_count))
                name = res.group(1)
                fixed_length = res.group(2)
                if fixed_length:
                    fixed_length = fixed_length[1:-1]
                continue
    
            if not separator:
                separator = token
                if separator != '=':
                     raise RpcGenError('Expected "=" after name \"%s\" got %s'
                                       % (name, token))
                continue
    
            if not tag_set:
                tag_set = 1
                if not re.match(r'^(0x)?[0-9]+$', token):
                    raise RpcGenError('Expected tag number: \"%s\"' % entry)
                tag = int(token, 0)
                continue
    
            raise RpcGenError('Cannot parse \"%s\"' % entry)
    
        if not tag_set:
            raise RpcGenError('Need tag number: \"%s\"' % entry)
    
        # Create the right entry
        if entry_type == 'bytes':
            if fixed_length:
                newentry = factory.EntryBytes(entry_type, name, tag, fixed_length)
            else:
                newentry = factory.EntryVarBytes(entry_type, name, tag)
        elif entry_type == 'int' and not fixed_length:
            newentry = factory.EntryInt(entry_type, name, tag)
        elif entry_type == 'int64' and not fixed_length:
            newentry = factory.EntryInt(entry_type, name, tag, bits=64)
        elif entry_type == 'string' and not fixed_length:
            newentry = factory.EntryString(entry_type, name, tag)
        else:
            res = structref.match(entry_type)
            if res:
                # References another struct defined in our file
                newentry = factory.EntryStruct(entry_type, name, tag, res.group(1))
            else:
                raise RpcGenError('Bad type: "%s" in "%s"' % (entry_type, entry))
    
        structs = []
    
        if optional:
            newentry.MakeOptional()
        if array:
            newentry.MakeArray()
    
        newentry.SetStruct(newstruct)
        newentry.SetLineCount(line_count)
        newentry.Verify()
    
        if array:
            # We need to encapsulate this entry into a struct
            newname = newentry.Name()+ '_array'
    
            # Now borgify the new entry.
            newentry = factory.EntryArray(newentry)
            newentry.SetStruct(newstruct)
            newentry.SetLineCount(line_count)
            newentry.MakeArray()
    
        newstruct.AddEntry(newentry)
    
        return structs
    
    def ProcessStruct(factory, data):
        tokens = data.split(' ')
    
        # First three tokens are: 'struct' 'name' '{'
        newstruct = factory.Struct(tokens[1])
    
        inside = ' '.join(tokens[3:-1])
    
        tokens = inside.split(';')
    
        structs = []
    
        for entry in tokens:
            entry = NormalizeLine(entry)
            if not entry:
                continue
    
            # It's possible that new structs get defined in here
            structs.extend(ProcessOneEntry(factory, newstruct, entry))
    
        structs.append(newstruct)
        return structs
    
    def GetNextStruct(file):
        global line_count
        global cppdirect
    
        got_struct = 0
    
        processed_lines = []
    
        have_c_comment = 0
        data = ''
        while 1:
            line = file.readline()
            if not line:
                break
    
            line_count += 1
            line = line[:-1]
    
            if not have_c_comment and re.search(r'/\*', line):
                if re.search(r'/\*.*?\*/', line):
                    line = re.sub(r'/\*.*?\*/', '', line)
                else:
                    line = re.sub(r'/\*.*$', '', line)
                    have_c_comment = 1
    
            if have_c_comment:
                if not re.search(r'\*/', line):
                    continue
                have_c_comment = 0
                line = re.sub(r'^.*\*/', '', line)
    
            line = NormalizeLine(line)
    
            if not line:
                continue
    
            if not got_struct:
                if re.match(r'#include ["<].*[>"]', line):
                    cppdirect.append(line)
                    continue
    
                if re.match(r'^#(if( |def)|endif)', line):
                    cppdirect.append(line)
                    continue
    
                if re.match(r'^#define', line):
                    headerdirect.append(line)
                    continue
    
                if not structdef.match(line):
                    raise RpcGenError('Missing struct on line %d: %s'
                                      % (line_count, line))
                else:
                    got_struct = 1
                    data += line
                continue
    
            # We are inside the struct
            tokens = line.split('}')
            if len(tokens) == 1:
                data += ' ' + line
                continue
    
            if len(tokens[1]):
                raise RpcGenError('Trailing garbage after struct on line %d'
                                  % line_count)
    
            # We found the end of the struct
            data += ' %s}' % tokens[0]
            break
    
        # Remove any comments, that might be in there
        data = re.sub(r'/\*.*\*/', '', data)
    
        return data
    
    
    def Parse(factory, file):
        """
        Parses the input file and returns C code and corresponding header file.
        """
    
        entities = []
    
        while 1:
            # Just gets the whole struct nicely formatted
            data = GetNextStruct(file)
    
            if not data:
                break
    
            entities.extend(ProcessStruct(factory, data))
    
        return entities
    
    class CCodeGenerator:
        def __init__(self):
            pass
    
        def GuardName(self, name):
            # Use the complete provided path to the input file, with all
            # non-identifier characters replaced with underscores, to
            # reduce the chance of a collision between guard macros.
            return '_' + nonident.sub('_', name).upper() + '_'
    
        def HeaderPreamble(self, name):
            guard = self.GuardName(name)
            pre = (
                '/*\n'
                ' * Automatically generated from %s\n'
                ' */\n\n'
                '#ifndef %s\n'
                '#define %s\n\n' ) % (
                name, guard, guard)
    
            for statement in headerdirect:
                pre += '%s\n' % statement
            if headerdirect:
                pre += '\n'
    
            pre += (
                '#include <event2/util.h> /* for ev_uint*_t */\n'
                '#include <event2/rpc.h>\n'
            )
    
            return pre
    
        def HeaderPostamble(self, name):
            guard = self.GuardName(name)
            return '#endif  /* %s */' % guard
    
        def BodyPreamble(self, name, header_file):
            global _NAME
            global _VERSION
    
            slash = header_file.rfind('/')
            if slash != -1:
                header_file = header_file[slash+1:]
    
            pre = ( '/*\n'
                    ' * Automatically generated from %s\n'
                    ' * by %s/%s.  DO NOT EDIT THIS FILE.\n'
                    ' */\n\n' ) % (name, _NAME, _VERSION)
            pre += ( '#include <stdlib.h>\n'
                     '#include <string.h>\n'
                     '#include <assert.h>\n'
                     '#include <event-config.h>\n'
                     '#include <event2/event.h>\n'
                     '#include <event2/buffer.h>\n'
                     '#include <event2/tag.h>\n\n'
                     '#ifdef _EVENT___func__\n'
                     '#define __func__ _EVENT___FUNC__\n'
                     '#endif\n\n'
                     )
    
            for statement in cppdirect:
                pre += '%s\n' % statement
    
            pre += '\n#include "%s"\n\n' % header_file
    
            pre += 'void event_err(int eval, const char *fmt, ...);\n'
            pre += 'void event_warn(const char *fmt, ...);\n'
            pre += 'void event_errx(int eval, const char *fmt, ...);\n'
            pre += 'void event_warnx(const char *fmt, ...);\n\n'
    
            return pre
    
        def HeaderFilename(self, filename):
            return '.'.join(filename.split('.')[:-1]) + '.h'
    
        def CodeFilename(self, filename):
            return '.'.join(filename.split('.')[:-1]) + '.gen.c'
    
        def Struct(self, name):
            return StructCCode(name)
    
        def EntryBytes(self, entry_type, name, tag, fixed_length):
            return EntryBytes(entry_type, name, tag, fixed_length)
    
        def EntryVarBytes(self, entry_type, name, tag):
            return EntryVarBytes(entry_type, name, tag)
    
        def EntryInt(self, entry_type, name, tag, bits=32):
            return EntryInt(entry_type, name, tag, bits)
    
        def EntryString(self, entry_type, name, tag):
            return EntryString(entry_type, name, tag)
    
        def EntryStruct(self, entry_type, name, tag, struct_name):
            return EntryStruct(entry_type, name, tag, struct_name)
    
        def EntryArray(self, entry):
            return EntryArray(entry)
    
    class Usage(RpcGenError):
        def __init__(self, argv0):
            RpcGenError.__init__("usage: %s input.rpc [[output.h] output.c]"
                                 % argv0)
    
    class CommandLine:
        def __init__(self, argv):
            self.filename = None
            self.header_file = None
            self.impl_file = None
            self.factory = CCodeGenerator()
    
            if len(argv) < 2 or len(argv) > 4:
                raise Usage(argv[0])
    
            self.filename = argv[1].replace('\\', '/')
            if len(argv) == 3:
                self.impl_file = argv[2].replace('\\', '/')
            if len(argv) == 4:
                self.header_file = argv[2].replace('\\', '/')
                self.impl_file = argv[3].replace('\\', '/')
    
            if not self.filename:
                raise Usage(argv[0])
    
            if not self.impl_file:
                self.impl_file = self.factory.CodeFilename(self.filename)
    
            if not self.header_file:
                self.header_file = self.factory.HeaderFilename(self.impl_file)
    
            if not self.impl_file.endswith('.c'):
                raise RpcGenError("can only generate C implementation files")
            if not self.header_file.endswith('.h'):
                raise RpcGenError("can only generate C header files")
    
        def run(self):
            filename = self.filename
            header_file = self.header_file
            impl_file = self.impl_file
            factory = self.factory
    
            print >>sys.stderr, 'Reading \"%s\"' % filename
    
            fp = open(filename, 'r')
            entities = Parse(factory, fp)
            fp.close()
    
            print >>sys.stderr, '... creating "%s"' % header_file
            header_fp = open(header_file, 'w')
            print >>header_fp, factory.HeaderPreamble(filename)
    
            # Create forward declarations: allows other structs to reference
            # each other
            for entry in entities:
                entry.PrintForwardDeclaration(header_fp)
            print >>header_fp, ''
    
            for entry in entities:
                entry.PrintTags(header_fp)
                entry.PrintDeclaration(header_fp)
            print >>header_fp, factory.HeaderPostamble(filename)
            header_fp.close()
    
            print >>sys.stderr, '... creating "%s"' % impl_file
            impl_fp = open(impl_file, 'w')
            print >>impl_fp, factory.BodyPreamble(filename, header_file)
            for entry in entities:
                entry.PrintCode(impl_fp)
            impl_fp.close()
    
    if __name__ == '__main__':
        try:
            CommandLine(sys.argv).run()
            sys.exit(0)
    
        except RpcGenError, e:
            print >>sys.stderr, e
            sys.exit(1)
    
        except EnvironmentError, e:
            if e.filename and e.strerror:
                print >>sys.stderr, "%s: %s" % (e.filename, e.strerror)
                sys.exit(1)
            elif e.strerror:
                print >> sys.stderr, e.strerror
                sys.exit(1)
            else:
                raise