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#!/usr/bin/env python
# Copyright 2010,2011 Mozilla Foundation. All rights reserved.
#
# Redistribution and use in source and binary forms, with or without
# modification, are permitted provided that the following conditions are
# met:
#
# 1. Redistributions of source code must retain the above copyright
# notice, this list of conditions and the following disclaimer.
#
# 2. Redistributions in binary form must reproduce the above copyright
# notice, this list of conditions and the following disclaimer in
# the documentation and/or other materials provided with the
# distribution.
#
# THIS SOFTWARE IS PROVIDED BY THE MOZILLA FOUNDATION ``AS IS'' AND ANY
# EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
# IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
# PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE MOZILLA FOUNDATION OR
# CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
# EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
# PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
# PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY
# OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
# (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
# OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
#
# The views and conclusions contained in the software and documentation
# are those of the authors and should not be interpreted as representing
# official policies, either expressed or implied, of the Mozilla
# Foundation.
"""
A module for working with XPCOM Type Libraries.
The XPCOM Type Library File Format is described at:
http://www.mozilla.org/scriptable/typelib_file.html . It is used
to provide type information for calling methods on XPCOM objects
from scripting languages such as JavaScript.
This module provides a set of classes representing the parts of
a typelib in a high-level manner, as well as methods for reading
and writing them from files.
The usable public interfaces are currently:
Typelib.read(input_file) - read a typelib from a file on disk or file-like
object, return a Typelib object.
xpt_dump(filename) - read a typelib from a file on disk, dump
the contents to stdout in a human-readable
format.
Typelib() - construct a new Typelib object
Interface() - construct a new Interface object
Method() - construct a new object representing a method
defined on an Interface
Constant() - construct a new object representing a constant
defined on an Interface
Param() - construct a new object representing a parameter
to a method
SimpleType() - construct a new object representing a simple
data type
InterfaceType() - construct a new object representing a type that
is an IDL-defined interface
"""
from __future__ import with_statement
import os, sys
import struct
import operator
# header magic
XPT_MAGIC = "XPCOM\nTypeLib\r\n\x1a"
TYPELIB_VERSION = (1, 2)
class FileFormatError(Exception):
pass
class DataError(Exception):
pass
# Magic for creating enums
def M_add_class_attribs(attribs):
def foo(name, bases, dict_):
for v, k in attribs:
dict_[k] = v
return type(name, bases, dict_)
return foo
def enum(*names):
class Foo(object):
__metaclass__ = M_add_class_attribs(enumerate(names))
def __setattr__(self, name, value): # this makes it read-only
raise NotImplementedError
return Foo()
# Descriptor types as described in the spec
class Type(object):
"""
Data type of a method parameter or return value. Do not instantiate
this class directly. Rather, use one of its subclasses.
"""
_prefixdescriptor = struct.Struct(">B")
Tags = enum(
# The first 18 entries are SimpleTypeDescriptor
'int8',
'int16',
'int32',
'int64',
'uint8',
'uint16',
'uint32',
'uint64',
'float',
'double',
'boolean',
'char',
'wchar_t',
'void',
# the following four values are only valid as pointers
'nsIID',
'DOMString',
'char_ptr',
'wchar_t_ptr',
# InterfaceTypeDescriptor
'Interface',
# InterfaceIsTypeDescriptor
'InterfaceIs',
# ArrayTypeDescriptor
'Array',
# StringWithSizeTypeDescriptor
'StringWithSize',
# WideStringWithSizeTypeDescriptor
'WideStringWithSize',
#XXX: These are also SimpleTypes (but not in the spec)
# http://hg.mozilla.org/mozilla-central/annotate/0e0e2516f04e/xpcom/typelib/xpt/tools/xpt_dump.c#l69
'UTF8String',
'CString',
'AString',
'jsval',
)
def __init__(self, pointer=False, reference=False):
self.pointer = pointer
self.reference = reference
if reference and not pointer:
raise Exception("If reference is True pointer must be True too")
@staticmethod
def decodeflags(byte):
"""
Given |byte|, an unsigned uint8 containing flag bits,
decode the flag bits as described in
http://www.mozilla.org/scriptable/typelib_file.html#TypeDescriptor
and return a dict of flagname: (True|False) suitable
for passing to Type.__init__ as **kwargs.
"""
return {'pointer': bool(byte & 0x80),
'reference': bool(byte & 0x20),
}
def encodeflags(self):
"""
Encode the flag bits of this Type object. Returns a byte.
"""
flags = 0
if self.pointer:
flags |= 0x80
if self.reference:
flags |= 0x20
return flags
@staticmethod
def read(typelib, map, data_pool, offset):
"""
Read a TypeDescriptor at |offset| from the mmaped file |map| with
data pool offset |data_pool|. Returns (Type, next offset),
where |next offset| is an offset suitable for reading the data
following this TypeDescriptor.
"""
start = data_pool + offset - 1
(data,) = Type._prefixdescriptor.unpack_from(map, start)
# first three bits are the flags
flags = data & 0xE0
flags = Type.decodeflags(flags)
# last five bits is the tag
tag = data & 0x1F
offset += Type._prefixdescriptor.size
t = None
if tag <= Type.Tags.wchar_t_ptr or tag >= Type.Tags.UTF8String:
t = SimpleType.get(data, tag, flags)
elif tag == Type.Tags.Interface:
t, offset = InterfaceType.read(typelib, map, data_pool, offset, flags)
elif tag == Type.Tags.InterfaceIs:
t, offset = InterfaceIsType.read(typelib, map, data_pool, offset, flags)
elif tag == Type.Tags.Array:
t, offset = ArrayType.read(typelib, map, data_pool, offset, flags)
elif tag == Type.Tags.StringWithSize:
t, offset = StringWithSizeType.read(typelib, map, data_pool, offset, flags)
elif tag == Type.Tags.WideStringWithSize:
t, offset = WideStringWithSizeType.read(typelib, map, data_pool, offset, flags)
return t, offset
def write(self, typelib, file):
"""
Write a TypeDescriptor to |file|, which is assumed
to be seeked to the proper position. For types other than
SimpleType, this is not sufficient for writing the TypeDescriptor,
and the subclass method must be called.
"""
file.write(Type._prefixdescriptor.pack(self.encodeflags() | self.tag))
class SimpleType(Type):
"""
A simple data type. (SimpleTypeDescriptor from the typelib specification.)
"""
_cache = {}
def __init__(self, tag, **kwargs):
Type.__init__(self, **kwargs)
self.tag = tag
@staticmethod
def get(data, tag, flags):
"""
Get a SimpleType object representing |data| (a TypeDescriptorPrefix).
May return an already-created object. If no cached object is found,
construct one with |tag| and |flags|.
"""
if data not in SimpleType._cache:
SimpleType._cache[data] = SimpleType(tag, **flags)
return SimpleType._cache[data]
def __str__(self):
s = "unknown"
if self.tag == Type.Tags.char_ptr and self.pointer:
return "string"
if self.tag == Type.Tags.wchar_t_ptr and self.pointer:
return "wstring"
for t in dir(Type.Tags):
if self.tag == getattr(Type.Tags, t):
s = t
break
if self.pointer:
if self.reference:
s += " &"
else:
s += " *"
return s
class InterfaceType(Type):
"""
A type representing a pointer to an IDL-defined interface.
(InterfaceTypeDescriptor from the typelib specification.)
"""
_descriptor = struct.Struct(">H")
def __init__(self, iface, pointer=True, **kwargs):
if not pointer:
raise DataError, "InterfaceType is not valid with pointer=False"
Type.__init__(self, pointer=pointer, **kwargs)
self.iface = iface
self.tag = Type.Tags.Interface
@staticmethod
def read(typelib, map, data_pool, offset, flags):
"""
Read an InterfaceTypeDescriptor at |offset| from the mmaped
file |map| with data pool offset |data_pool|.
Returns (InterfaceType, next offset),
where |next offset| is an offset suitable for reading the data
following this InterfaceTypeDescriptor.
"""
if not flags['pointer']:
return None, offset
start = data_pool + offset - 1
(iface_index,) = InterfaceType._descriptor.unpack_from(map, start)
offset += InterfaceType._descriptor.size
iface = None
# interface indices are 1-based
if iface_index > 0 and iface_index <= len(typelib.interfaces):
iface = typelib.interfaces[iface_index - 1]
return InterfaceType(iface, **flags), offset
def write(self, typelib, file):
"""
Write an InterfaceTypeDescriptor to |file|, which is assumed
to be seeked to the proper position.
"""
Type.write(self, typelib, file)
# write out the interface index (1-based)
file.write(InterfaceType._descriptor.pack(typelib.interfaces.index(self.iface) + 1))
def __str__(self):
if self.iface:
return self.iface.name
return "unknown interface"
class InterfaceIsType(Type):
"""
A type representing an interface described by one of the other
arguments to the method. (InterfaceIsTypeDescriptor from the
typelib specification.)
"""
_descriptor = struct.Struct(">B")
_cache = {}
def __init__(self, param_index, pointer=True, **kwargs):
if not pointer:
raise DataError, "InterfaceIsType is not valid with pointer=False"
Type.__init__(self, pointer=pointer, **kwargs)
self.param_index = param_index
self.tag = Type.Tags.InterfaceIs
@staticmethod
def read(typelib, map, data_pool, offset, flags):
"""
Read an InterfaceIsTypeDescriptor at |offset| from the mmaped
file |map| with data pool offset |data_pool|.
Returns (InterfaceIsType, next offset),
where |next offset| is an offset suitable for reading the data
following this InterfaceIsTypeDescriptor.
May return a cached value.
"""
if not flags['pointer']:
return None, offset
start = data_pool + offset - 1
(param_index,) = InterfaceIsType._descriptor.unpack_from(map, start)
offset += InterfaceIsType._descriptor.size
if param_index not in InterfaceIsType._cache:
InterfaceIsType._cache[param_index] = InterfaceIsType(param_index, **flags)
return InterfaceIsType._cache[param_index], offset
def write(self, typelib, file):
"""
Write an InterfaceIsTypeDescriptor to |file|, which is assumed
to be seeked to the proper position.
"""
Type.write(self, typelib, file)
file.write(InterfaceIsType._descriptor.pack(self.param_index))
def __str__(self):
return "InterfaceIs *"
class ArrayType(Type):
"""
A type representing an Array of elements of another type, whose
size and length are passed as separate parameters to a method.
(ArrayTypeDescriptor from the typelib specification.)
"""
_descriptor = struct.Struct(">BB")
def __init__(self, element_type, size_is_arg_num, length_is_arg_num,
pointer=True, **kwargs):
if not pointer:
raise DataError, "ArrayType is not valid with pointer=False"
Type.__init__(self, pointer=pointer, **kwargs)
self.element_type = element_type
self.size_is_arg_num = size_is_arg_num
self.length_is_arg_num = length_is_arg_num
self.tag = Type.Tags.Array
@staticmethod
def read(typelib, map, data_pool, offset, flags):
"""
Read an ArrayTypeDescriptor at |offset| from the mmaped
file |map| with data pool offset |data_pool|.
Returns (ArrayType, next offset),
where |next offset| is an offset suitable for reading the data
following this ArrayTypeDescriptor.
"""
if not flags['pointer']:
return None, offset
start = data_pool + offset - 1
(size_is_arg_num, length_is_arg_num) = ArrayType._descriptor.unpack_from(map, start)
offset += ArrayType._descriptor.size
t, offset = Type.read(typelib, map, data_pool, offset)
return ArrayType(t, size_is_arg_num, length_is_arg_num, **flags), offset
def write(self, typelib, file):
"""
Write an ArrayTypeDescriptor to |file|, which is assumed
to be seeked to the proper position.
"""
Type.write(self, typelib, file)
file.write(ArrayType._descriptor.pack(self.size_is_arg_num,
self.length_is_arg_num))
self.element_type.write(typelib, file)
def __str__(self):
return "%s []" % str(self.element_type)
class StringWithSizeType(Type):
"""
A type representing a UTF-8 encoded string whose size and length
are passed as separate arguments to a method. (StringWithSizeTypeDescriptor
from the typelib specification.)
"""
_descriptor = struct.Struct(">BB")
def __init__(self, size_is_arg_num, length_is_arg_num,
pointer=True, **kwargs):
if not pointer:
raise DataError, "StringWithSizeType is not valid with pointer=False"
Type.__init__(self, pointer=pointer, **kwargs)
self.size_is_arg_num = size_is_arg_num
self.length_is_arg_num = length_is_arg_num
self.tag = Type.Tags.StringWithSize
@staticmethod
def read(typelib, map, data_pool, offset, flags):
"""
Read an StringWithSizeTypeDescriptor at |offset| from the mmaped
file |map| with data pool offset |data_pool|.
Returns (StringWithSizeType, next offset),
where |next offset| is an offset suitable for reading the data
following this StringWithSizeTypeDescriptor.
"""
if not flags['pointer']:
return None, offset
start = data_pool + offset - 1
(size_is_arg_num, length_is_arg_num) = StringWithSizeType._descriptor.unpack_from(map, start)
offset += StringWithSizeType._descriptor.size
return StringWithSizeType(size_is_arg_num, length_is_arg_num, **flags), offset
def write(self, typelib, file):
"""
Write a StringWithSizeTypeDescriptor to |file|, which is assumed
to be seeked to the proper position.
"""
Type.write(self, typelib, file)
file.write(StringWithSizeType._descriptor.pack(self.size_is_arg_num,
self.length_is_arg_num))
def __str__(self):
return "string_s"
class WideStringWithSizeType(Type):
"""
A type representing a UTF-16 encoded string whose size and length
are passed as separate arguments to a method.
(WideStringWithSizeTypeDescriptor from the typelib specification.)
"""
_descriptor = struct.Struct(">BB")
def __init__(self, size_is_arg_num, length_is_arg_num,
pointer=True, **kwargs):
if not pointer:
raise DataError, "WideStringWithSizeType is not valid with pointer=False"
Type.__init__(self, pointer=pointer, **kwargs)
self.size_is_arg_num = size_is_arg_num
self.length_is_arg_num = length_is_arg_num
self.tag = Type.Tags.WideStringWithSize
@staticmethod
def read(typelib, map, data_pool, offset, flags):
"""
Read an WideStringWithSizeTypeDescriptor at |offset| from the mmaped
file |map| with data pool offset |data_pool|.
Returns (WideStringWithSizeType, next offset),
where |next offset| is an offset suitable for reading the data
following this WideStringWithSizeTypeDescriptor.
"""
if not flags['pointer']:
return None, offset
start = data_pool + offset - 1
(size_is_arg_num, length_is_arg_num) = WideStringWithSizeType._descriptor.unpack_from(map, start)
offset += WideStringWithSizeType._descriptor.size
return WideStringWithSizeType(size_is_arg_num, length_is_arg_num, **flags), offset
def write(self, typelib, file):
"""
Write a WideStringWithSizeTypeDescriptor to |file|, which is assumed
to be seeked to the proper position.
"""
Type.write(self, typelib, file)
file.write(WideStringWithSizeType._descriptor.pack(self.size_is_arg_num,
self.length_is_arg_num))
def __str__(self):
return "wstring_s"
class Param(object):
"""
A parameter to a method, or the return value of a method.
(ParamDescriptor from the typelib specification.)
"""
_descriptorstart = struct.Struct(">B")
def __init__(self, type, in_=True, out=False, retval=False,
shared=False, dipper=False, optional=False):
"""
Construct a Param object with the specified |type| and
flags. Params default to "in".
"""
self.type = type
self.in_ = in_
self.out = out
self.retval = retval
self.shared = shared
self.dipper = dipper
self.optional = optional
@staticmethod
def decodeflags(byte):
"""
Given |byte|, an unsigned uint8 containing flag bits,
decode the flag bits as described in
http://www.mozilla.org/scriptable/typelib_file.html#ParamDescriptor
and return a dict of flagname: (True|False) suitable
for passing to Param.__init__ as **kwargs
"""
return {'in_': bool(byte & 0x80),
'out': bool(byte & 0x40),
'retval': bool(byte & 0x20),
'shared': bool(byte & 0x10),
'dipper': bool(byte & 0x08),
#XXX: Not in the spec, see:
# http://hg.mozilla.org/mozilla-central/annotate/0e0e2516f04e/xpcom/typelib/xpt/public/xpt_struct.h#l456
'optional': bool(byte & 0x04),
}
def encodeflags(self):
"""
Encode the flags of this Param. Return a byte suitable for
writing to a typelib file.
"""
flags = 0
if self.in_:
flags |= 0x80
if self.out:
flags |= 0x40
if self.retval:
flags |= 0x20
if self.shared:
flags |= 0x10
if self.dipper:
flags |= 0x08
if self.optional:
flags |= 0x04
return flags
@staticmethod
def read(typelib, map, data_pool, offset):
"""
Read a ParamDescriptor at |offset| from the mmaped file |map| with
data pool offset |data_pool|. Returns (Param, next offset),
where |next offset| is an offset suitable for reading the data
following this ParamDescriptor.
"""
start = data_pool + offset - 1
(flags,) = Param._descriptorstart.unpack_from(map, start)
# only the first five bits are flags
flags &= 0xFC
flags = Param.decodeflags(flags)
offset += Param._descriptorstart.size
t, offset = Type.read(typelib, map, data_pool, offset)
p = Param(t, **flags)
return p, offset
def write(self, typelib, file):
"""
Write a ParamDescriptor to |file|, which is assumed to be seeked
to the correct position.
"""
file.write(Param._descriptorstart.pack(self.encodeflags()))
self.type.write(typelib, file)
def prefix(self):
"""
Return a human-readable string representing the flags set
on this Param.
"""
s = ""
if self.out:
if self.in_:
s = "inout "
else:
s = "out "
else:
s = "in "
if self.dipper:
s += "dipper "
if self.retval:
s += "retval "
if self.shared:
s += "shared "
if self.optional:
s += "optional "
return s
def __str__(self):
return self.prefix() + str(self.type)
class Method(object):
"""
A method of an interface, defining its associated parameters
and return value.
(MethodDescriptor from the typelib specification.)
"""
_descriptorstart = struct.Struct(">BIB")
def __init__(self, name, result,
params=[], getter=False, setter=False, notxpcom=False,
constructor=False, hidden=False, optargc=False,
implicit_jscontext=False):
self.name = name
self._name_offset = 0
self.getter = getter
self.setter = setter
self.notxpcom = notxpcom
self.constructor = constructor
self.hidden = hidden
self.optargc = optargc
self.implicit_jscontext = implicit_jscontext
self.params = list(params)
if result and not isinstance(result, Param):
raise Exception("result must be a Param!")
self.result = result
def read_params(self, typelib, map, data_pool, offset, num_args):
"""
Read |num_args| ParamDescriptors representing this Method's arguments
from the mmaped file |map| with data pool at the offset |data_pool|,
starting at |offset| into self.params. Returns the offset
suitable for reading the data following the ParamDescriptor array.
"""
for i in range(num_args):
p, offset = Param.read(typelib, map, data_pool, offset)
self.params.append(p)
return offset
def read_result(self, typelib, map, data_pool, offset):
"""
Read a ParamDescriptor representing this Method's return type
from the mmaped file |map| with data pool at the offset |data_pool|,
starting at |offset| into self.result. Returns the offset
suitable for reading the data following the ParamDescriptor.
"""
self.result, offset = Param.read(typelib, map, data_pool, offset)
return offset
@staticmethod
def decodeflags(byte):
"""
Given |byte|, an unsigned uint8 containing flag bits,
decode the flag bits as described in
http://www.mozilla.org/scriptable/typelib_file.html#MethodDescriptor
and return a dict of flagname: (True|False) suitable
for passing to Method.__init__ as **kwargs
"""
return {'getter': bool(byte & 0x80),
'setter': bool(byte & 0x40),
'notxpcom': bool(byte & 0x20),
'constructor': bool(byte & 0x10),
'hidden': bool(byte & 0x08),
# Not in the spec, see
# http://hg.mozilla.org/mozilla-central/annotate/0e0e2516f04e/xpcom/typelib/xpt/public/xpt_struct.h#l489
'optargc': bool(byte & 0x04),
'implicit_jscontext': bool(byte & 0x02),
}
def encodeflags(self):
"""
Encode the flags of this Method object, return a byte suitable
for writing to a typelib file.
"""
flags = 0
if self.getter:
flags |= 0x80
if self.setter:
flags |= 0x40
if self.notxpcom:
flags |= 0x20
if self.constructor:
flags |= 0x10
if self.hidden:
flags |= 0x08
if self.optargc:
flags |= 0x04
if self.implicit_jscontext:
flags |= 0x02
return flags
@staticmethod
def read(typelib, map, data_pool, offset):
"""
Read a MethodDescriptor at |offset| from the mmaped file |map| with
data pool offset |data_pool|. Returns (Method, next offset),
where |next offset| is an offset suitable for reading the data
following this MethodDescriptor.
"""
start = data_pool + offset - 1
flags, name_offset, num_args = Method._descriptorstart.unpack_from(map, start)
# only the first seven bits are flags
flags &= 0xFE
flags = Method.decodeflags(flags)
name = Typelib.read_string(map, data_pool, name_offset)
m = Method(name, None, **flags)
offset += Method._descriptorstart.size
offset = m.read_params(typelib, map, data_pool, offset, num_args)
offset = m.read_result(typelib, map, data_pool, offset)
return m, offset
def write(self, typelib, file):
"""
Write a MethodDescriptor to |file|, which is assumed to be
seeked to the right position.
"""
file.write(Method._descriptorstart.pack(self.encodeflags(),
self._name_offset,
len(self.params)))
for p in self.params:
p.write(typelib, file)
self.result.write(typelib, file)
def write_name(self, file, data_pool_offset):
"""
Write this method's name to |file|.
Assumes that |file| is currently seeked to an unused portion
of the data pool.
"""
if self.name:
self._name_offset = file.tell() - data_pool_offset + 1
file.write(self.name + "\x00")
else:
self._name_offset = 0
class Constant(object):
"""
A constant value of a specific type defined on an interface.
(ConstantDesciptor from the typelib specification.)
"""
_descriptorstart = struct.Struct(">I")
# Actual value is restricted to this set of types
#XXX: the spec lies, the source allows a bunch more
# http://hg.mozilla.org/mozilla-central/annotate/9c85f9aaec8c/xpcom/typelib/xpt/src/xpt_struct.c#l689
typemap = {Type.Tags.int16: '>h',
Type.Tags.uint16: '>H',
Type.Tags.int32: '>i',
Type.Tags.uint32: '>I'}
def __init__(self, name, type, value):
self.name = name
self._name_offset = 0
self.type = type
self.value = value
@staticmethod
def read(typelib, map, data_pool, offset):
"""
Read a ConstDescriptor at |offset| from the mmaped file |map| with
data pool offset |data_pool|. Returns (Constant, next offset),
where |next offset| is an offset suitable for reading the data
following this ConstDescriptor.
"""
start = data_pool + offset - 1
(name_offset,) = Constant._descriptorstart.unpack_from(map, start)
name = Typelib.read_string(map, data_pool, name_offset)
offset += Constant._descriptorstart.size
# Read TypeDescriptor
t, offset = Type.read(typelib, map, data_pool, offset)
c = None
if isinstance(t, SimpleType) and t.tag in Constant.typemap:
tt = Constant.typemap[t.tag]
start = data_pool + offset - 1
(val,) = struct.unpack_from(tt, map, start)
offset += struct.calcsize(tt)
c = Constant(name, t, val)
return c, offset
def write(self, typelib, file):
"""
Write a ConstDescriptor to |file|, which is assumed
to be seeked to the proper position.
"""
file.write(Constant._descriptorstart.pack(self._name_offset))
self.type.write(typelib, file)
tt = Constant.typemap[self.type.tag]
file.write(struct.pack(tt, self.value))
def write_name(self, file, data_pool_offset):
"""
Write this constants's name to |file|.
Assumes that |file| is currently seeked to an unused portion
of the data pool.
"""
if self.name:
self._name_offset = file.tell() - data_pool_offset + 1
file.write(self.name + "\x00")
else:
self._name_offset = 0
def __repr__(self):
return "Constant(%s, %s, %d)" % (self.name, str(self.type), self.value)
class Interface(object):
"""
An Interface represents an object, with its associated methods
and constant values.
(InterfaceDescriptor from the typelib specification.)
"""
_direntry = struct.Struct(">16sIII")
_descriptorstart = struct.Struct(">HH")
UNRESOLVED_IID = "00000000-0000-0000-0000-000000000000"
def __init__(self, name, iid=UNRESOLVED_IID, namespace="",
resolved=False, parent=None, methods=[], constants=[],
scriptable=False, function=False, builtinclass=False):
self.resolved = resolved
#TODO: should validate IIDs!
self.iid = iid
self.name = name
self.namespace = namespace
# if unresolved, all the members following this are unusable
self.parent = parent
self.methods = list(methods)
self.constants = list(constants)
self.scriptable = scriptable
self.function = function
self.builtinclass = builtinclass
# For sanity, if someone constructs an Interface and passes
# in methods or constants, then it's resolved.
if self.methods or self.constants:
# make sure it has a valid IID
if self.iid == Interface.UNRESOLVED_IID:
raise DataError, "Cannot instantiate Interface %s containing methods or constants with an unresolved IID" % self.name
self.resolved = True
# These are only used for writing out the interface
self._descriptor_offset = 0
self._name_offset = 0
self._namespace_offset = 0
self.xpt_filename = None
def __repr__(self):
return "Interface('%s', '%s', '%s', methods=%s)" % (self.name, self.iid, self.namespace, self.methods)
def __str__(self):
return "Interface(name='%s', iid='%s')" % (self.name, self.iid)
def __hash__(self):
return hash((self.name, self.iid))
def __cmp__(self, other):
c = cmp(self.iid, other.iid)
if c != 0:
return c
c = cmp(self.name, other.name)
if c != 0:
return c
c = cmp(self.namespace, other.namespace)
if c != 0:
return c
# names and IIDs are the same, check resolved
if self.resolved != other.resolved:
if self.resolved:
return -1
else:
return 1
else:
# both unresolved, but names and IIDs are the same, so equal
return 0
#TODO: actually compare methods etc
return 0
def read_descriptor(self, typelib, map, data_pool):
offset = self._descriptor_offset
if offset == 0:
return
start = data_pool + offset - 1
parent, num_methods = Interface._descriptorstart.unpack_from(map, start)
if parent > 0 and parent <= len(typelib.interfaces):
self.parent = typelib.interfaces[parent - 1]
# Read methods
offset += Interface._descriptorstart.size
for i in range(num_methods):
m, offset = Method.read(typelib, map, data_pool, offset)
self.methods.append(m)
# Read constants
start = data_pool + offset - 1
(num_constants, ) = struct.unpack_from(">H", map, start)
offset = offset + struct.calcsize(">H")
for i in range(num_constants):
c, offset = Constant.read(typelib, map, data_pool, offset)
self.constants.append(c)
# Read flags
start = data_pool + offset - 1
(flags, ) = struct.unpack_from(">B", map, start)
offset = offset + struct.calcsize(">B")
# only the first two bits are flags
flags &= 0xE0
if flags & 0x80:
self.scriptable = True
if flags & 0x40:
self.function = True
if flags & 0x20:
self.builtinclass = True
self.resolved = True
def write_directory_entry(self, file):
"""
Write an InterfaceDirectoryEntry for this interface
to |file|, which is assumed to be seeked to the correct offset.
"""
file.write(Interface._direntry.pack(Typelib.string_to_iid(self.iid),
self._name_offset,
self._namespace_offset,
self._descriptor_offset))
def write(self, typelib, file, data_pool_offset):
"""
Write an InterfaceDescriptor to |file|, which is assumed
to be seeked to the proper position. If this interface
is not resolved, do not write any data.
"""
if not self.resolved:
self._descriptor_offset = 0
return
self._descriptor_offset = file.tell() - data_pool_offset + 1
parent_idx = 0
if self.parent:
parent_idx = typelib.interfaces.index(self.parent) + 1
file.write(Interface._descriptorstart.pack(parent_idx, len(self.methods)))
for m in self.methods:
m.write(typelib, file)
file.write(struct.pack(">H", len(self.constants)))
for c in self.constants:
c.write(typelib, file)
flags = 0
if self.scriptable:
flags |= 0x80
if self.function:
flags |= 0x40
if self.builtinclass:
flags |= 0x20
file.write(struct.pack(">B", flags))
def write_names(self, file, data_pool_offset):
"""
Write this interface's name and namespace to |file|,
as well as the names of all of its methods and constants.
Assumes that |file| is currently seeked to an unused portion
of the data pool.
"""
if self.name:
self._name_offset = file.tell() - data_pool_offset + 1
file.write(self.name + "\x00")
else:
self._name_offset = 0
if self.namespace:
self._namespace_offset = file.tell() - data_pool_offset + 1
file.write(self.namespace + "\x00")
else:
self._namespace_offset = 0
for m in self.methods:
m.write_name(file, data_pool_offset)
for c in self.constants:
c.write_name(file, data_pool_offset)
class Typelib(object):
"""
A typelib represents one entire typelib file and all the interfaces
referenced within, whether defined entirely within the typelib or
merely referenced by name or IID.
Typelib objects may be instantiated directly and populated with data,
or the static Typelib.read method may be called to read one from a file.
"""
_header = struct.Struct(">16sBBHIII")
def __init__(self, version=TYPELIB_VERSION, interfaces=[], annotations=[]):
"""
Instantiate a new Typelib.
"""
self.version = version
self.interfaces = list(interfaces)
self.annotations = list(annotations)
self.filename = None
@staticmethod
def iid_to_string(iid):
"""
Convert a 16-byte IID into a UUID string.
"""
def hexify(s):
return ''.join(["%02x" % ord(x) for x in s])
return "%s-%s-%s-%s-%s" % (hexify(iid[:4]), hexify(iid[4:6]),
hexify(iid[6:8]), hexify(iid[8:10]),
hexify(iid[10:]))
@staticmethod
def string_to_iid(iid_str):
"""
Convert a UUID string into a 16-byte IID.
"""
s = iid_str.replace('-','')
return ''.join([chr(int(s[i:i+2], 16)) for i in range(0, len(s), 2)])
@staticmethod
def read_string(map, data_pool, offset):
if offset == 0:
return ""
sz = map.find('\x00', data_pool + offset - 1)
if sz == -1:
return ""
return map[data_pool + offset - 1:sz]
@staticmethod
def read(input_file):
"""
Read a typelib from |input_file| and return
the constructed Typelib object. |input_file| can be a filename
or a file-like object.
"""
filename = ""
data = None
expected_size = None
if isinstance(input_file, basestring):
filename = input_file
with open(input_file, "rb") as f:
st = os.fstat(f.fileno())
data = f.read(st.st_size)
expected_size = st.st_size
else:
data = input_file.read()
(magic,
major_ver,
minor_ver,
num_interfaces,
file_length,
interface_directory_offset,
data_pool_offset) = Typelib._header.unpack_from(data)
if magic != XPT_MAGIC:
raise FileFormatError, "Bad magic: %s" % magic
xpt = Typelib((major_ver, minor_ver))
xpt.filename = filename
if expected_size and file_length != expected_size:
raise FileFormatError, "File is of wrong length, got %d bytes, expected %d" % (expected_size, file_length)
#XXX: by spec this is a zero-based file offset. however,
# the xpt_xdr code always subtracts 1 from data offsets
# (because that's what you do in the data pool) so it
# winds up accidentally treating this as 1-based.
# Filed as: https://bugzilla.mozilla.org/show_bug.cgi?id=575343
interface_directory_offset -= 1
# make a half-hearted attempt to read Annotations,
# since XPIDL doesn't produce any anyway.
start = Typelib._header.size
(anno, ) = struct.unpack_from(">B", data, start)
islast = anno & 0x80
tag = anno & 0x7F
if tag == 0: # EmptyAnnotation
xpt.annotations.append(None)
# We don't bother handling PrivateAnnotations or anything
for i in range(num_interfaces):
# iid, name, namespace, interface_descriptor
start = interface_directory_offset + i * Interface._direntry.size
ide = Interface._direntry.unpack_from(data, start)
iid = Typelib.iid_to_string(ide[0])
name = Typelib.read_string(data, data_pool_offset, ide[1])
namespace = Typelib.read_string(data, data_pool_offset, ide[2])
iface = Interface(name, iid, namespace)
iface._descriptor_offset = ide[3]
iface.xpt_filename = xpt.filename
xpt.interfaces.append(iface)
for iface in xpt.interfaces:
iface.read_descriptor(xpt, data, data_pool_offset)
return xpt
def __repr__(self):
return "<Typelib with %d interfaces>" % len(self.interfaces)
def _sanityCheck(self):
"""
Check certain assumptions about data contained in this typelib.
Sort the interfaces array by IID, check that all interfaces
referenced by methods exist in the array.
"""
self.interfaces.sort()
for i in self.interfaces:
if i.parent and i.parent not in self.interfaces:
raise DataError, "Interface %s has parent %s not present in typelib!" % (i.name, i.parent.name)
for m in i.methods:
for n, p in enumerate(m.params):
if isinstance(p, InterfaceType) and \
p.iface not in self.interfaces:
raise DataError, "Interface method %s::%s, parameter %d references interface %s not present in typelib!" % (i.name, m.name, n, p.iface.name)
if isinstance(m.result, InterfaceType) and m.result.iface not in self.interfaces:
raise DataError, "Interface method %s::%s, result references interface %s not present in typelib!" % (i.name, m.name, m.result.iface.name)
def writefd(self, fd):
# write out space for a header + one empty annotation,
# padded to 4-byte alignment.
headersize = (Typelib._header.size + 1)
if headersize % 4:
headersize += 4 - headersize % 4
fd.write("\x00" * headersize)
# save this offset, it's the interface directory offset.
interface_directory_offset = fd.tell()
# write out space for an interface directory
fd.write("\x00" * Interface._direntry.size * len(self.interfaces))
# save this offset, it's the data pool offset.
data_pool_offset = fd.tell()
# write out all the interface descriptors to the data pool
for i in self.interfaces:
i.write_names(fd, data_pool_offset)
i.write(self, fd, data_pool_offset)
# now, seek back and write the header
file_len = fd.tell()
fd.seek(0)
fd.write(Typelib._header.pack(XPT_MAGIC,
TYPELIB_VERSION[0],
TYPELIB_VERSION[1],
len(self.interfaces),
file_len,
interface_directory_offset,
data_pool_offset))
# write an empty annotation
fd.write(struct.pack(">B", 0x80))
# now write the interface directory
#XXX: bug-compatible with existing xpt lib, put it one byte
# ahead of where it's supposed to be.
fd.seek(interface_directory_offset - 1)
for i in self.interfaces:
i.write_directory_entry(fd)
def write(self, output_file):
"""
Write the contents of this typelib to |output_file|,
which can be either a filename or a file-like object.
"""
self._sanityCheck()
if isinstance(output_file, basestring):
with open(output_file, "wb") as f:
self.writefd(f)
else:
self.writefd(output_file)
def dump(self, out):
"""
Print a human-readable listing of the contents of this typelib
to |out|, in the format of xpt_dump.
"""
out.write("""Header:
Major version: %d
Minor version: %d
Number of interfaces: %d
Annotations:\n""" % (self.version[0], self.version[1], len(self.interfaces)))
for i, a in enumerate(self.annotations):
if a is None:
out.write(" Annotation #%d is empty.\n" % i)
out.write("\nInterface Directory:\n")
for i in self.interfaces:
out.write(" - %s::%s (%s):\n" % (i.namespace, i.name, i.iid))
if not i.resolved:
out.write(" [Unresolved]\n")
else:
if i.parent:
out.write(" Parent: %s::%s\n" % (i.parent.namespace,
i.parent.name))
out.write(""" Flags:
Scriptable: %s
BuiltinClass: %s
Function: %s\n""" % (i.scriptable and "TRUE" or "FALSE",
i.builtinclass and "TRUE" or "FALSE",
i.function and "TRUE" or "FALSE"))
out.write(" Methods:\n")
if len(i.methods) == 0:
out.write(" No Methods\n")
else:
for m in i.methods:
out.write(" %s%s%s%s%s%s%s %s %s(%s);\n" % (
m.getter and "G" or " ",
m.setter and "S" or " ",
m.hidden and "H" or " ",
m.notxpcom and "N" or " ",
m.constructor and "C" or " ",
m.optargc and "O" or " ",
m.implicit_jscontext and "J" or " ",
str(m.result.type),
m.name,
m.params and ", ".join(str(p) for p in m.params) or ""
))
out.write(" Constants:\n")
if len(i.constants) == 0:
out.write(" No Constants\n")
else:
for c in i.constants:
out.write(" %s %s = %d;\n" % (c.type, c.name, c.value))
def xpt_dump(file):
"""
Dump the contents of |file| to stdout in the format of xpt_dump.
"""
t = Typelib.read(file)
t.dump(sys.stdout)
def xpt_link(inputs):
"""
Link all of the xpt files in |inputs| together and return the result
as a Typelib object. All entries in inputs may be filenames or
file-like objects.
"""
def read_input(i):
if isinstance(i, Typelib):
return i
return Typelib.read(i)
if not inputs:
print >>sys.stderr, "Usage: xpt_link <destination file> <input files>"
return None
# This is the aggregate list of interfaces.
interfaces = []
# This will be a dict of replaced interface -> replaced with
# containing interfaces that were replaced with interfaces from
# another typelib, and the interface that replaced them.
merged_interfaces = {}
for f in inputs:
t = read_input(f)
interfaces.extend(t.interfaces)
# Sort interfaces by name so we can merge adjacent duplicates
interfaces.sort(key=operator.attrgetter('name'))
Result = enum('Equal', # Interfaces the same, doesn't matter
'NotEqual', # Interfaces differ, keep both
'KeepFirst', # Replace second interface with first
'KeepSecond')# Replace first interface with second
def compare(i, j):
"""
Compare two interfaces, determine if they're equal or
completely different, or should be merged (and indicate which
one to keep in that case).
"""
if i == j:
# Arbitrary, just pick one
return Result.Equal
if i.name != j.name:
if i.iid == j.iid and i.iid != Interface.UNRESOLVED_IID:
# Same IID but different names: raise an exception.
raise DataError, \
"Typelibs contain definitions of interface %s" \
" with different names (%s (%s) vs %s (%s))!" % \
(i.iid, i.name, i.xpt_filename, j.name, j.xpt_filename)
# Otherwise just different interfaces.
return Result.NotEqual
# Interfaces have the same name, so either they need to be merged
# or there's a data error. Sort out which one to keep
if i.resolved != j.resolved:
# prefer resolved interfaces over unresolved
if j.resolved:
assert i.iid == j.iid or i.iid == Interface.UNRESOLVED_IID
# keep j
return Result.KeepSecond
else:
assert i.iid == j.iid or j.iid == Interface.UNRESOLVED_IID
# replace j with i
return Result.KeepFirst
elif i.iid != j.iid:
# Prefer unresolved interfaces with valid IIDs
if j.iid == Interface.UNRESOLVED_IID:
# replace j with i
assert not j.resolved
return Result.KeepFirst
elif i.iid == Interface.UNRESOLVED_IID:
# keep j
assert not i.resolved
return Result.KeepSecond
else:
# Same name but different IIDs: raise an exception.
raise DataError, \
"Typelibs contain definitions of interface %s" \
" with different IIDs (%s (%s) vs %s (%s))!" % \
(i.name, i.iid, i.xpt_filename, \
j.iid, j.xpt_filename)
raise DataError, "No idea what happened here: %s:%s (%s), %s:%s (%s)" % \
(i.name, i.iid, i.xpt_filename, j.name, j.iid, j.xpt_filename)
# Compare interfaces pairwise to find duplicates that should be merged.
i = 1
while i < len(interfaces):
res = compare(interfaces[i-1], interfaces[i])
if res == Result.NotEqual:
i += 1
elif res == Result.Equal:
# Need to drop one but it doesn't matter which
del interfaces[i]
elif res == Result.KeepFirst:
merged_interfaces[interfaces[i]] = interfaces[i-1]
del interfaces[i]
elif res == Result.KeepSecond:
merged_interfaces[interfaces[i-1]] = interfaces[i]
del interfaces[i-1]
# Now fixup any merged interfaces
def checkType(t):
if isinstance(t, InterfaceType) and t.iface in merged_interfaces:
t.iface = merged_interfaces[t.iface]
elif isinstance(t, ArrayType) and \
isinstance(t.element_type, InterfaceType) and \
t.element_type.iface in merged_interfaces:
t.element_type.iface = merged_interfaces[t.element_type.iface]
for i in interfaces:
# Replace parent references
if i.parent in merged_interfaces:
i.parent = merged_interfaces[i.parent]
for m in i.methods:
# Replace InterfaceType params and return values
checkType(m.result.type)
for p in m.params:
checkType(p.type)
# Re-sort interfaces (by IID)
interfaces.sort()
return Typelib(interfaces=interfaces)
if __name__ == '__main__':
if len(sys.argv) < 3:
print >>sys.stderr, "xpt <dump|link> <files>"
sys.exit(1)
if sys.argv[1] == 'dump':
xpt_dump(sys.argv[2])
elif sys.argv[1] == 'link':
xpt_link(sys.argv[3:]).write(sys.argv[2])

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