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kc3-lang/libevent/event_rpcgen.py

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  • Author : Niels Provos
    Date : 2006-05-17 13:13:31
    Hash : ebf5333f
    Message : oops. the enums were actually creating symbols svn:r212

  • event_rpcgen.py
  • #!/usr/bin/env python
    #
    # Copyright (c) 2005 Niels Provos <provos@citi.umich.edu>
    # All rights reserved.
    #
    # Generates marshalling code based on libevent.
    
    import sys
    import re
    
    #
    _NAME = "event_rpcgen.py"
    _VERSION = "0.1"
    _STRUCT_RE = '[a-z][a-z_0-9]*'
    
    # Globals
    line_count = 0
    
    leading = re.compile(r'^\s+')
    trailing = re.compile(r'\s+$')
    white = re.compile(r'^\s+')
    cppcomment = re.compile(r'\/\/.*$')
    cppdirect = []
    
    # 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()):
                print >>sys.stderr, ( 'Entry "%s" duplicates tag number '
                                      '%d from "%s" around line %d' ) % (
                    entry.Name(), entry.Tag(),
                    self._tags[entry.Tag()], line_count)
                sys.exit(1)
            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 PrintIdented(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)
    
        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 {' % self._name
            for entry in self._entries:
                dcl = entry.Declaration()
                dcl.extend(
                    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.PrintIdented(file, '  ', dcl)
            print >>file, ''
            for entry in self._entries:
                print >>file, '  u_int8_t %s_set;' % entry.Name()
            print >>file, '};\n'
    
            print >>file, (
                'struct %s *%s_new();\n' % (self._name, self._name) +
                'void %s_free(struct %s *);\n' % (self._name, self._name) +
                'void %s_clear(struct %s *);\n' % (self._name, self._name) +
                'void %s_marshal(struct evbuffer *, const struct %s *);\n' % (
                self._name, self._name) +
                'int %s_unmarshal(struct %s *, struct evbuffer *);\n' % (
                self._name, self._name) +
                'int %s_complete(struct %s *);' % (self._name, self._name)
                )
            print >>file, ('void evtag_marshal_%s(struct evbuffer *, u_int8_t, '
                           'const struct %s *);') % ( self._name, self._name)
            print >>file, ('int evtag_unmarshal_%s(struct evbuffer *, u_int8_t, '
                           'struct %s *);') % ( self._name, self._name)
    
            # Write a setting function of every variable
            for entry in self._entries:
                self.PrintIdented(file, '', entry.AssignDeclaration(
                    entry.AssignFuncName()))
                self.PrintIdented(file, '', entry.GetDeclaration(
                    entry.GetFuncName()))
                if entry.Array():
                    self.PrintIdented(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
    
            # Creation
            print >>file, ( 'struct %s *\n' % self._name +
                            '%s_new()\n' % self._name +
                            '{\n'
                            '  struct %s *tmp;\n' % self._name +
                            '  if ((tmp = malloc(sizeof(struct %s))) == NULL) {\n'
                            '    event_warn("%%s: malloc", __func__);\n'
                            '    return (NULL);\n' % self._name +
                            '  }'
                            )
            for entry in self._entries:
                self.PrintIdented(file, '  ', entry.CodeNew('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.PrintIdented(file, '', entry.CodeAdd())
                print >>file, ''
                
            # Assigning
            for entry in self._entries:
                self.PrintIdented(file, '', entry.CodeAssign())
                print >>file, ''
    
            # Getting
            for entry in self._entries:
                self.PrintIdented(file, '', entry.CodeGet())
                print >>file, ''
                
            # Clearing
            print >>file, ( 'void\n'
                            '%s_clear(struct %s *tmp)\n' % (
                self._name, self._name)+
                            '{'
                            )
            for entry in self._entries:
                self.PrintIdented(file, '  ', entry.CodeClear('tmp'))
    
            print >>file, '}\n'
    
            # Freeing
            print >>file, ( 'void\n'
                            '%s_free(struct %s *tmp)\n' % (
                self._name, self._name)+
                            '{'
                            )
            for entry in self._entries:
                self.PrintIdented(file, '  ', entry.CodeFree('tmp'))
    
            print >>file, ('  free(tmp);\n'
                           '}\n')
    
            # Marshaling
            print >>file, ('void\n'
                           '%s_marshal(struct evbuffer *evbuf, '
                           'const struct %s *tmp)' % (self._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.PrintIdented(
                    file, indent,
                    entry.CodeMarshal('evbuf', self.EntryTagName(entry), 'tmp'))
                if entry.Optional():
                    print >>file, '  }'
    
            print >>file, '}\n'
                           
            # Unmarshaling
            print >>file, ('int\n'
                           '%s_unmarshal(struct %s *tmp, '
                           ' struct evbuffer *evbuf)\n' % (
                self._name, self._name) +
                           '{\n'
                           '  u_int8_t tag;\n'
                           '  while (EVBUFFER_LENGTH(evbuf) > 0) {\n'
                           '    if (evtag_peek(evbuf, &tag) == -1)\n'
                           '      return (-1);\n'
                           '    switch (tag) {\n'
                           )
            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.PrintIdented(
                    file, '        ',
                    entry.CodeUnmarshal('evbuf',
                                        self.EntryTagName(entry), '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 (%s_complete(tmp) == -1)\n' % self._name +
                            '    return (-1);')
    
            # Successfully decoded
            print >>file, ( '  return (0);\n'
                            '}\n')
    
            # Checking if a structure has all the required data
            print >>file, (
                'int\n'
                '%s_complete(struct %s *msg)\n' % (self._name, self._name) +
                '{' )
            for entry in self._entries:
                self.PrintIdented(
                    file, '  ',
                    entry.CodeComplete('msg'))
            print >>file, (
                '  return (0);\n'
                '}\n' )
    
            # Complete message unmarshaling
            print >>file, (
                'int\n'
                'evtag_unmarshal_%s(struct evbuffer *evbuf, u_int8_t need_tag, '
                ' struct %s *msg)'
                ) % (self._name, self._name)
            print >>file, (
                '{\n'
                '  u_int8_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 (%s_unmarshal(msg, tmp) == -1)\n'
                '    goto error;\n'
                '\n'
                '  res = 0;\n'
                '\n'
                ' error:\n'
                '  evbuffer_free(tmp);\n'
                '  return (res);\n'
                '}\n' ) % self._name
    
            # Complete message marshaling
            print >>file, (
                'void\n'
                'evtag_marshal_%s(struct evbuffer *evbuf, u_int8_t tag, '
                'const struct %s *msg)\n' % (self._name, self._name) +
                '{\n'
                '  struct evbuffer *_buf = evbuffer_new();\n'
                '  assert(_buf != NULL);\n'
                '  evbuffer_drain(_buf, -1);\n'
                '  %s_marshal(_buf, msg);\n' % self._name +
                '  evtag_marshal(evbuf, tag, EVBUFFER_DATA(_buf), '
                'EVBUFFER_LENGTH(_buf));\n'
                '  evbuffer_free(_buf);\n'
                '}\n' )
    
    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
    
        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 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',
                     '%s_%s_get(struct %s *msg, %s *value)' % (
                self._struct.Name(), self._name,
                self._struct.Name(), self._ctype),
                     '{',
                     '  if (msg->%s_set != 1)' % self._name,
                     '    return (-1);',
                     '  *value = msg->%s_data;' % self._name,
                     '  return (0);',
                     '}' ]
            return code
            
        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',
                     '%s_%s_assign(struct %s *msg, const %s value)' % (
                self._struct.Name(), self._name,
                self._struct.Name(), self._ctype),
                     '{',
                     '  msg->%s_set = 1;' % self._name,
                     '  msg->%s_data = value;' % self._name,
                     '  return (0);',
                     '}' ]
            return code
    
        def CodeClear(self, structname):
            code = [ '%s->%s_set = 0;' % (structname, self.Name()) ]
    
            return code
            
        def CodeComplete(self, structname):
            if self.Optional():
                return []
            
            code = [ 'if (!%s->%s_set)' % (structname, self.Name()),
                     '  return (-1);' ]
    
            return code
    
        def CodeFree(self, name):
            return []
    
        def CodeNew(self, name):
            code = [ '%s->%s_assign = %s_%s_assign;' % (
                name, self._name, self._struct.Name(), self._name ),
                     '%s->%s_get = %s_%s_get;' % (
                name, self._name, self._struct.Name(), self._name ),
            ]
            if self.Array():
                code.append(
                    '%s->%s_add = %s_%s_add;' % (
                    name, self._name, self._struct.Name(), self._name ) )
            return code
    
        def Verify(self):
            if self.Array() and not self._can_be_array:
                print >>sys.stderr, (
                    'Entry "%s" cannot be created as an array '
                    'around line %d' ) % (self._name, self.LineCount())
                sys.exit(1)
            if not self._struct:
                print >>sys.stderr, (
                    'Entry "%s" does not know which struct it belongs to '
                    'around line %d' ) % (self._name, self.LineCount())
                sys.exit(1)
            if self._optional and self._array:
                print >>sys.stderr,  ( 'Entry "%s" has illegal combination of '
                                       'optional and array around line %d' ) % (
                    self._name, self.LineCount() )
                sys.exit(1)
    
    class EntryBytes(Entry):
        def __init__(self, type, name, tag, length):
            # Init base class
            Entry.__init__(self, type, name, tag)
    
            self._length = length
            self._ctype = 'u_int8_t'
    
        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  = ['u_int8_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):
            code = [  'if (evtag_unmarshal_fixed(%s, %s, ' % (buf, tag_name) +
                      '%s->%s_data, ' % (var_name, self._name) +
                      'sizeof(%s->%s_data)) == -1) {' % (
                var_name, self._name),
                      '  event_warnx("%%s: failed to unmarshal %s", __func__);' % (
                self._name ),
                      '  return (-1);',
                      '}'
                      ]
            return code
    
        def CodeMarshal(self, buf, tag_name, var_name):
            code = ['evtag_marshal(%s, %s, %s->%s_data, sizeof(%s->%s_data));' % (
                buf, tag_name, var_name, self._name, var_name, self._name )]
            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 CodeNew(self, name):
            code  = ['memset(%s->%s_data, 0, sizeof(%s->%s_data));' % (
                name, self._name, name, self._name)]
            code.extend(Entry.CodeNew(self, name))
            return code
    
        def Verify(self):
            if not self._length:
                print >>sys.stderr, 'Entry "%s" needs a length around line %d' % (
                    self._name, self.LineCount() )
                sys.exit(1)
    
            Entry.Verify(self)
    
    class EntryInt(Entry):
        def __init__(self, type, name, tag):
            # Init base class
            Entry.__init__(self, type, name, tag)
    
            self._ctype = 'u_int32_t'
    
        def CodeUnmarshal(self, buf, tag_name, var_name):
            code = ['if (evtag_unmarshal_int(%s, %s, &%s->%s_data) == -1) {' % (
                buf, tag_name, var_name, self._name),
                      '  event_warnx("%%s: failed to unmarshal %s", __func__);' % (
                self._name ),
                    '  return (-1);',
                    '}' ] 
            return code
    
        def CodeMarshal(self, buf, tag_name, var_name):
            code = ['evtag_marshal_int(%s, %s, %s->%s_data);' % (
                buf, tag_name, var_name, self._name)]
            return code
    
        def Declaration(self):
            dcl  = ['u_int32_t %s_data;' % self._name]
    
            return dcl
    
    class EntryString(Entry):
        def __init__(self, type, name, tag):
            # Init base class
            Entry.__init__(self, type, name, tag)
    
            self._ctype = 'char *'
    
        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),
                     '{',
                     '  if (msg->%s_data != NULL)' % name,
                     '    free(msg->%s_data);' % name,
                     '  if ((msg->%s_data = strdup(value)) == NULL)' % name,
                     '    return (-1);',
                     '  msg->%s_set = 1;' % name,
                     '  return (0);',
                     '}' ]
            return code
            
        def CodeUnmarshal(self, buf, tag_name, var_name):
            code = ['if (evtag_unmarshal_string(%s, %s, &%s->%s_data) == -1) {' % (
                buf, tag_name, var_name, self._name),
                    '  event_warnx("%%s: failed to unmarshal %s", __func__);' % (
                self._name ),
                    '  return (-1);',
                    '}'
                    ]
            return code
    
        def CodeMarshal(self, buf, tag_name, var_name):
            code = ['evtag_marshal_string(%s, %s, %s->%s_data);' % (
                buf, tag_name, var_name, self._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 CodeNew(self, name):
            code  = ['%s->%s_data = NULL;' % (name, self._name)]
            code.extend(Entry.CodeNew(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._can_be_array = 1
            self._refname = refname
            self._ctype = 'struct %s' % refname
    
        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 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',
                     '%s_%s_assign(struct %s *msg, const %s *value)' % (
                self._struct.Name(), name,
                self._struct.Name(), self._ctype),
                     '{',
                     '  struct evbuffer *tmp = NULL;',
                     '  if (msg->%s_set) {' % name,
                     '    %s_clear(msg->%s_data);' % (self._refname, name),
                     '    msg->%s_set = 0;' % name,
                     '  } else {',
                     '    msg->%s_data = %s_new();' % (name, self._refname),
                     '    if (msg->%s_data == NULL) {' % name,
                     '      event_warn("%%s: %s_new()", __func__);' % (
                self._refname),
                     '      goto error;',
                     '    }',
                     '  }',
                     '  if ((tmp = evbuffer_new()) == NULL) {',
                     '    event_warn("%s: evbuffer_new()", __func__);',
                     '    goto error;',
                     '  }',
                     '  %s_marshal(tmp, value); ' % self._refname,
                     '  if (%s_unmarshal(msg->%s_data, tmp) == -1) {' % (
                self._refname, name ),
                     '    event_warnx("%%s: %s_unmarshal", __func__);' % (
                self._refname),
                     '    goto error;',
                     '  }',
                     '  msg->%s_set = 1;' % name,
                     '  evbuffer_free(tmp);',
                     '  return (0);',
                     ' error:',
                     '  if (tmp != NULL)',
                     '    evbuffer_free(tmp);',
                     '  if (msg->%s_data != NULL) {' % name,
                     '    %s_free(msg->%s_data);' % (self._refname, name),
                     '    msg->%s_data = NULL;' % name,
                     '  }',
                     '  return (-1);',
                     '}' ]
            return code
            
        def CodeComplete(self, structname):
            if self.Optional():
                code = [ 'if (%s->%s_set && %s_complete(%s->%s_data) == -1)' % (
                    structname, self.Name(),
                    self._refname, structname, self.Name()),
                         '  return (-1);' ]
            else:
                code = [ 'if (%s_complete(%s->%s_data) == -1)' % (
                    self._refname, structname, self.Name()),
                         '  return (-1);' ]
    
            return code
        
        def CodeUnmarshal(self, buf, tag_name, var_name):
            code = ['%s->%s_data = %s_new();' % (
                var_name, self._name, self._refname),
                    'if (%s->%s_data == NULL)' % (var_name, self._name),
                    '  return (-1);',
                    'if (evtag_unmarshal_%s(%s, %s, %s->%s_data) == -1) {' % (
                self._refname, buf, tag_name, var_name, self._name),
                      '  event_warnx("%%s: failed to unmarshal %s", __func__);' % (
                self._name ),
                    '  return (-1);',
                    '}'
                    ]
            return code
    
        def CodeMarshal(self, buf, tag_name, var_name):
            code = ['evtag_marshal_%s(%s, %s, %s->%s_data);' % (
                self._refname, buf, tag_name, var_name, self._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 CodeNew(self, name):
            code  = ['%s->%s_data = NULL;' % (name, self._name)]
            code.extend(Entry.CodeNew(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  = ['struct %s *%s_data;' % (self._refname, self._name)]
    
            return dcl
    
    class EntryVarBytes(Entry):
        def __init__(self, type, name, tag):
            # Init base class
            Entry.__init__(self, type, name, tag)
    
            self._ctype = 'u_int8_t *'
    
        def GetDeclaration(self, funcname):
            code = [ 'int %s(struct %s *, %s *, u_int32_t *);' % (
                funcname, self._struct.Name(), self._ctype ) ]
            return code
            
        def AssignDeclaration(self, funcname):
            code = [ 'int %s(struct %s *, const %s, u_int32_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, u_int32_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, u_int32_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):
            code = ['if (evtag_payload_length(%s, &%s->%s_length) == -1)' % (
                buf, var_name, self._name),
                    '  return (-1);',
                    # We do not want DoS opportunities
                    'if (%s->%s_length > EVBUFFER_LENGTH(%s))' % (
                var_name, self._name, buf),
                    '  return (-1);',
                    'if ((%s->%s_data = malloc(%s->%s_length)) == NULL)' % (
                var_name, self._name, var_name, self._name),
                    '  return (-1);',
                    'if (evtag_unmarshal_fixed(%s, %s, %s->%s_data, '
                    '%s->%s_length) == -1) {' % (
                buf, tag_name, var_name, self._name, var_name, self._name),
                    '  event_warnx("%%s: failed to unmarshal %s", __func__);' % (
                self._name ),
                    '  return (-1);',
                    '}'
                    ]
            return code
    
        def CodeMarshal(self, buf, tag_name, var_name):
            code = ['evtag_marshal(%s, %s, %s->%s_data, %s->%s_length);' % (
                buf, tag_name, var_name, self._name, var_name, self._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_length = 0;' % (structname, self.Name()),
                     '  %s->%s_set = 0;' % (structname, self.Name()),
                     '}'
                     ]
    
            return code
            
        def CodeNew(self, name):
            code  = ['%s->%s_data = NULL;' % (name, self._name),
                     '%s->%s_length = 0;' % (name, self._name) ]
            code.extend(Entry.CodeNew(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  = ['u_int8_t *%s_data;' % self._name,
                    'u_int32_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 = 'struct %s' % self._refname
    
        def GetDeclaration(self, funcname):
            """Allows direct access to elements of the array."""
            code = [ 'int %s(struct %s *, int, %s **);' % (
                funcname, self._struct.Name(), self._ctype ) ]
            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 = [ '%s *%s(struct %s *);' % (
                self._ctype, funcname, self._struct.Name() ) ]
            return code
            
        def CodeGet(self):
            name = self._name
            code = [ 'int',
                     '%s_%s_get(struct %s *msg, int offset, %s **value)' % (
                self._struct.Name(), name,
                self._struct.Name(), self._ctype),
                     '{',
                     '  if (msg->%s_set != 1)' % name,
                     '    return (-1);',
                     '  if (offset >= msg->%s_length)' % name,
                     '    return (-1);',
                     '  *value = msg->%s_data[offset];' % name,
                     '  return (0);',
                     '}' ]
            return code
            
        def CodeAssign(self):
            name = self._name
            code = [ 'int',
                     '%s_%s_assign(struct %s *msg, int off, const %s *value)' % (
                self._struct.Name(), name,
                self._struct.Name(), self._ctype),
                     '{',
                     '  struct evbuffer *tmp = NULL;',
                     '  if (msg->%s_set != 1)' % name,
                     '    return (-1);',
                     '  if (off >= msg->%s_length)' % name,
                     '    return (-1);',
                     '',
                     '  %s_clear(msg->%s_data[off]);' % (self._refname, name),
                     '  if ((tmp = evbuffer_new()) == NULL) {',
                     '    event_warn("%s: evbuffer_new()", __func__);',
                     '    goto error;',
                     '  }',
                     '  %s_marshal(tmp, value); ' % self._refname,
                     '  if (%s_unmarshal(msg->%s_data[off], tmp) == -1) {' % (
                self._refname, name ),
                     '    event_warnx("%%s: %s_unmarshal", __func__);' % (
                self._refname),
                     '    goto error;',
                     '  }',
                     '  evbuffer_free(tmp);',
                     '  return (0);',
                     ' error:',
                     '  if (tmp != NULL)',
                     '    evbuffer_free(tmp);',
                     '  %s_clear(msg->%s_data[off]);' % (self._refname, name),
                     '  return (-1);',
                     '}' ]
            return code
            
        def CodeAdd(self):
            name = self._name
            code = [
                '%s *' % self._ctype, 
                '%s_%s_add(struct %s *msg)' % (
                self._struct.Name(), name, self._struct.Name()),
                '{',
                '  msg->%s_length++;' % name,
                '  msg->%s_data = (struct %s**)realloc(msg->%s_data, '
                '  msg->%s_length * sizeof(struct %s*));' % (
                name, self._refname, name, name, self._refname ),
                '  if (msg->%s_data == NULL)' % name,
                '    return (NULL);',
                '  msg->%s_data[msg->%s_length - 1] = %s_new();' % (
                name, name, self._refname),
                '  if (msg->%s_data[msg->%s_length - 1] == NULL) {' % (name, name),
                '    msg->%s_length--; ' % name,
                '    return (NULL);',
                '  }',
                '  msg->%s_set = 1;' % name,
                '  return (msg->%s_data[msg->%s_length - 1]);' % (name, name),
                '}'
                ]
            return code
            
        def CodeComplete(self, structname):
            code = []
            if self.Optional():
                code.append( 'if (%s->%s_set)'  % (structname, self.Name()))
    
            code.extend(['{',
                         '  int i;',
                         '  for (i = 0; i < %s->%s_length; ++i) {' % (
                    structname, self.Name()),
                         '    if (%s_complete(%s->%s_data[i]) == -1)' % (
                    self._refname, structname, self.Name()),
                         '      return (-1);',
                         '  }',
                         '}'
                         ])
    
            return code
        
        def CodeUnmarshal(self, buf, tag_name, var_name):
            code = ['if (%s_%s_add(%s) == NULL)' % (
                self._struct.Name(), self._name, var_name),
                    '  return (-1);',
                    'if (evtag_unmarshal_%s(%s, %s, '
                    '%s->%s_data[%s->%s_length - 1]) == -1) {' % (
                self._refname, buf, tag_name, var_name, self._name,
                var_name, self._name),
                    '  %s->%s_length--; ' % (var_name, self._name),
                    '  event_warnx("%%s: failed to unmarshal %s", __func__);' % (
                self._name ),
                    '  return (-1);',
                    '}'
                    ]
            return code
    
        def CodeMarshal(self, buf, tag_name, var_name):
            code = ['{',
                    '  int i;',
                    '  for (i = 0; i < %s->%s_length; ++i) {' % (
                var_name, self._name),
                    '    evtag_marshal_%s(%s, %s, %s->%s_data[i]);' % (
                self._refname, buf, tag_name, var_name, self._name),
                    '  }',
                    '}'
                    ]
            return code
    
        def CodeClear(self, structname):
            code = [ 'if (%s->%s_set == 1) {' % (structname, self.Name()),
                     '  int i;',
                     '  for (i = 0; i < %s->%s_length; ++i) {' % (
                structname, self.Name()),
                     '    %s_free(%s->%s_data[i]);' % (
                self._refname, structname, self.Name()),
                     '  }',
                     '  free(%s->%s_data);' % (structname, self.Name()),
                     '  %s->%s_data = NULL;' % (structname, self.Name()),
                     '  %s->%s_set = 0;' % (structname, self.Name()),
                     '  %s->%s_length = 0;' % (structname, self.Name()),
                     '}'
                     ]
    
            return code
            
        def CodeNew(self, name):
            code  = ['%s->%s_data = NULL;' % (name, self._name),
                     '%s->%s_length = 0;' % (name, self._name)]
            code.extend(Entry.CodeNew(self, name))
            return code
    
        def CodeFree(self, name):
            code  = ['if (%s->%s_data != NULL) {' % (name, self._name),
                     '  int i;',
                     '  for (i = 0; i < %s->%s_length; ++i) {' % (
                name, self._name),
                     '    %s_free(%s->%s_data[i]); ' % (
                self._refname, name, self._name),
                     '    %s->%s_data[i] = NULL;' % (name, self._name),
                     '  }',
                     '  free(%s->%s_data);' % (name, self._name),
                     '  %s->%s_data = NULL;' % (name, self._name),
                     '  %s->%s_length = 0;' % (name, self._name),
                     '}'
                     ]
    
            return code
    
        def Declaration(self):
            dcl  = ['struct %s **%s_data;' % (self._refname, self._name),
                    'int %s_length;' % self._name]
    
            return dcl
    
    def NormalizeLine(line):
        global leading
        global trailing
        global white
        global cppcomment
        
        line = cppcomment.sub('', line)
        line = leading.sub('', line)
        line = trailing.sub('', line)
        line = white.sub(' ', line)
    
        return line
    
    def ProcessOneEntry(newstruct, entry):
        optional = 0
        array = 0
        type = ''
        name = ''
        tag = ''
        tag_set = None
        separator = ''
        fixed_length = ''
    
        tokens = entry.split(' ')
        while tokens:
            token = tokens[0]
            tokens = tokens[1:]
    
            if not type:
                if not optional and token == 'optional':
                    optional = 1
                    continue
    
                if not array and token == 'array':
                    array = 1
                    continue
    
            if not type:
                type = token
                continue
    
            if not name:
                res = re.match(r'^([^\[\]]+)(\[.*\])?$', token)
                if not res:
                    print >>sys.stderr, 'Cannot parse name: \"%s\" around %d' % (
                        entry, line_count)
                    sys.exit(1)
                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 != '=':
                    print >>sys.stderr, 'Expected "=" after name \"%s\" got %s' % (
                        name, token)
                    sys.exit(1)
                continue
    
            if not tag_set:
                tag_set = 1
                if not re.match(r'^[0-9]+$', token):
                    print >>sys.stderr, 'Expected tag number: \"%s\"' % entry
                    sys.exit(1)
                tag = int(token)
                continue
    
            print >>sys.stderr, 'Cannot parse \"%s\"' % entry
            sys.exit(1)
    
        if not tag_set:
            print >>sys.stderr, 'Need tag number: \"%s\"' % entry
            sys.exit(1)
    
        # Create the right entry
        if type == 'bytes':
            if fixed_length:
                newentry = EntryBytes(type, name, tag, fixed_length)
            else:
                newentry = EntryVarBytes(type, name, tag)
        elif type == 'int' and not fixed_length:
            newentry = EntryInt(type, name, tag)
        elif type == 'string' and not fixed_length:
            newentry = EntryString(type, name, tag)
        else:
            res = re.match(r'^struct\[(%s)\]$' % _STRUCT_RE, type, re.IGNORECASE)
            if res:
                # References another struct defined in our file
                newentry = EntryStruct(type, name, tag, res.group(1))
            else:
                print >>sys.stderr, 'Bad type: "%s" in "%s"' % (type, entry)
                sys.exit(1)
    
        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 = EntryArray(newentry)
            newentry.SetStruct(newstruct)
            newentry.SetLineCount(line_count)
            newentry.MakeArray()
    
        newstruct.AddEntry(newentry)
    
        return structs
    
    def ProcessStruct(data):
        tokens = data.split(' ')
    
        # First three tokens are: 'struct' 'name' '{'
        newstruct = 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(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 = ''
        for line in file:
            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 not re.match(r'^struct %s {$' % _STRUCT_RE,
                                line, re.IGNORECASE):
                    print >>sys.stderr, 'Missing struct on line %d: %s' % (
                        line_count, line)
                    sys.exit(1)
                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]):
                print >>sys.stderr, 'Trailing garbage after struct on line %d' % (
                    line_count )
                sys.exit(1)
    
            # 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(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(data))
    
        return entities
    
    def GuardName(name):
        name = '_'.join(name.split('.'))
        name = '_'.join(name.split('/'))
        guard = '_'+name.upper()+'_'
    
        return guard
    
    def HeaderPreamble(name):
        guard = GuardName(name)
        pre = (
            '/*\n'
            ' * Automatically generated from %s\n'
            ' */\n\n'
            '#ifndef %s\n'
            '#define %s\n\n' ) % (
            name, guard, guard)
        pre += (
            '#define EVTAG_HAS(msg, member) ((msg)->member##_set == 1)\n'
            '#define EVTAG_ASSIGN(msg, member, args...) '
            '(*(msg)->member##_assign)(msg, ## args)\n'
            '#define EVTAG_GET(msg, member, args...) '
            '(*(msg)->member##_get)(msg, ## args)\n'
            '#define EVTAG_ADD(msg, member) (*(msg)->member##_add)(msg)\n'
            '#define EVTAG_LEN(msg, member) ((msg)->member##_length)\n'
            )
    
        return pre
         
    
    def HeaderPostamble(name):
        guard = GuardName(name)
        return '#endif  /* %s */' % guard
    
    def BodyPreamble(name):
        global _NAME
        global _VERSION
        
        header_file = '.'.join(name.split('.')[:-1]) + '.gen.h'
    
        pre = ( '/*\n'
                ' * Automatically generated from %s\n'
                ' * by %s/%s.  DO NOT EDIT THIS FILE.\n'
                ' */\n\n' ) % (name, _NAME, _VERSION)
        pre += ( '#include <sys/types.h>\n'
                 '#include <sys/time.h>\n'
                 '#include <stdlib.h>\n'
                 '#include <string.h>\n'
                 '#include <assert.h>\n'
                 '#include <event.h>\n\n' )
    
        for include in cppdirect:
            pre += '%s\n' % include
        
        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 main(argv):
        filename = argv[1]
    
        if filename.split('.')[-1] != 'rpc':
            ext = filename.split('.')[-1]
            print >>sys.stderr, 'Unrecognized file extension: %s' % ext
            sys.exit(1)
    
        print >>sys.stderr, 'Reading \"%s\"' % filename
    
        fp = open(filename, 'r')
        entities = Parse(fp)
        fp.close()
    
        header_file = '.'.join(filename.split('.')[:-1]) + '.gen.h'
        impl_file = '.'.join(filename.split('.')[:-1]) + '.gen.c'
    
        print >>sys.stderr, '... creating "%s"' % header_file
        header_fp = open(header_file, 'w')
        print >>header_fp, 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, HeaderPostamble(filename)
        header_fp.close()
    
        print >>sys.stderr, '... creating "%s"' % impl_file
        impl_fp = open(impl_file, 'w')
        print >>impl_fp, BodyPreamble(filename)
        for entry in entities:
            entry.PrintCode(impl_fp)
        impl_fp.close()
    
    if __name__ == '__main__':
        main(sys.argv)