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# ***** BEGIN LICENSE BLOCK *****
# Version: MPL 1.1/GPL 2.0/LGPL 2.1
#
# The contents of this file are subject to the Mozilla Public License Version
# 1.1 (the "License"); you may not use this file except in compliance with
# the License. You may obtain a copy of the License at
# http://www.mozilla.org/MPL/
#
# Software distributed under the License is distributed on an "AS IS" basis,
# WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License
# for the specific language governing rights and limitations under the
# License.
#
# The Original Code is Python XPCOM language bindings.
#
# The Initial Developer of the Original Code is
# ActiveState Tool Corp.
# Portions created by the Initial Developer are Copyright (C) 2001
# the Initial Developer. All Rights Reserved.
#
# Contributor(s):
# Mark Hammond <mhammond@skippinet.com.au> (original author)
#
# Alternatively, the contents of this file may be used under the terms of
# either the GNU General Public License Version 2 or later (the "GPL"), or
# the GNU Lesser General Public License Version 2.1 or later (the "LGPL"),
# in which case the provisions of the GPL or the LGPL are applicable instead
# of those above. If you wish to allow use of your version of this file only
# under the terms of either the GPL or the LGPL, and not to allow others to
# use your version of this file under the terms of the MPL, indicate your
# decision by deleting the provisions above and replace them with the notice
# and other provisions required by the GPL or the LGPL. If you do not delete
# the provisions above, a recipient may use your version of this file under
# the terms of any one of the MPL, the GPL or the LGPL.
#
# ***** END LICENSE BLOCK *****
from xpcom import xpcom_consts, _xpcom, client, nsError, logger
from xpcom import ServerException, COMException
import xpcom
import xpcom.server
import operator
import types
import logging
import sys
# Python 3 hacks:
if sys.version_info[0] >= 3:
long = int # pylint: disable=W0622,C0103
IID_nsISupports = _xpcom.IID_nsISupports
IID_nsIVariant = _xpcom.IID_nsIVariant
XPT_MD_IS_GETTER = xpcom_consts.XPT_MD_IS_GETTER
XPT_MD_IS_SETTER = xpcom_consts.XPT_MD_IS_SETTER
VARIANT_INT_TYPES = xpcom_consts.VTYPE_INT8, xpcom_consts.VTYPE_INT16, xpcom_consts.VTYPE_INT32, \
xpcom_consts.VTYPE_UINT8, xpcom_consts.VTYPE_UINT16, xpcom_consts.VTYPE_INT32
VARIANT_LONG_TYPES = xpcom_consts.VTYPE_INT64, xpcom_consts.VTYPE_UINT64
VARIANT_FLOAT_TYPES = xpcom_consts.VTYPE_FLOAT, xpcom_consts.VTYPE_DOUBLE
VARIANT_STRING_TYPES = xpcom_consts.VTYPE_CHAR, xpcom_consts.VTYPE_CHAR_STR, xpcom_consts.VTYPE_STRING_SIZE_IS, \
xpcom_consts.VTYPE_CSTRING
VARIANT_UNICODE_TYPES = xpcom_consts.VTYPE_WCHAR, xpcom_consts.VTYPE_DOMSTRING, xpcom_consts.VTYPE_WSTRING_SIZE_IS, \
xpcom_consts.VTYPE_ASTRING
_supports_primitives_map_ = {} # Filled on first use.
_interface_sequence_types_ = tuple, list
if sys.version_info[0] <= 2:
_string_types_ = str, unicode
else:
_string_types_ = bytes, str
XPTI_GetInterfaceInfoManager = _xpcom.XPTI_GetInterfaceInfoManager
def _GetNominatedInterfaces(obj):
ret = getattr(obj, "_com_interfaces_", None)
if ret is None: return None
# See if the user only gave one.
if type(ret) not in _interface_sequence_types_:
ret = [ret]
real_ret = []
# For each interface, walk to the root of the interface tree.
iim = XPTI_GetInterfaceInfoManager()
for interface in ret:
# Allow interface name or IID.
interface_info = None
if type(interface) in _string_types_:
try:
interface_info = iim.GetInfoForName(interface)
except COMException:
pass
if interface_info is None:
# Allow a real IID
interface_info = iim.GetInfoForIID(interface)
real_ret.append(interface_info.GetIID())
parent = interface_info.GetParent()
while parent is not None:
parent_iid = parent.GetIID()
if parent_iid == IID_nsISupports:
break
real_ret.append(parent_iid)
parent = parent.GetParent()
return real_ret
##
## ClassInfo support
##
## We cache class infos by class
class_info_cache = {}
def GetClassInfoForObject(ob):
if xpcom.server.tracer_unwrap is not None:
ob = xpcom.server.tracer_unwrap(ob)
klass = ob.__class__
ci = class_info_cache.get(klass)
if ci is None:
ci = DefaultClassInfo(klass)
ci = xpcom.server.WrapObject(ci, _xpcom.IID_nsIClassInfo, bWrapClient = 0)
class_info_cache[klass] = ci
return ci
class DefaultClassInfo:
_com_interfaces_ = _xpcom.IID_nsIClassInfo
def __init__(self, klass):
self.klass = klass
self.contractID = getattr(klass, "_reg_contractid_", None)
self.classDescription = getattr(klass, "_reg_desc_", None)
self.classID = getattr(klass, "_reg_clsid_", None)
self.implementationLanguage = 3 # Python - avoid lookups just for this
self.flags = 0 # what to do here??
self.interfaces = None
def get_classID(self):
if self.classID is None:
raise ServerException(nsError.NS_ERROR_NOT_IMPLEMENTED, "Class '%r' has no class ID" % (self.klass,))
return self.classID
def getInterfaces(self):
if self.interfaces is None:
self.interfaces = _GetNominatedInterfaces(self.klass)
return self.interfaces
def getHelperForLanguage(self, language):
return None # Not sure what to do here.
class DefaultPolicy:
def __init__(self, instance, iid):
self._obj_ = instance
self._nominated_interfaces_ = ni = _GetNominatedInterfaces(instance)
self._iid_ = iid
if ni is None:
raise ValueError("The object '%r' can not be used as a COM object" % (instance,))
# This is really only a check for the user
if __debug__:
if iid != IID_nsISupports and iid not in ni:
# The object may delegate QI.
delegate_qi = getattr(instance, "_query_interface_", None)
# Perform the actual QI and throw away the result - the _real_
# QI performed by the framework will set things right!
if delegate_qi is None or not delegate_qi(iid):
raise ServerException(nsError.NS_ERROR_NO_INTERFACE)
# Stuff for the magic interface conversion.
self._interface_info_ = None
self._interface_iid_map_ = {} # Cache - Indexed by (method_index, param_index)
def _QueryInterface_(self, com_object, iid):
# Framework allows us to return a single boolean integer,
# or a COM object.
if iid in self._nominated_interfaces_:
# We return the underlying object re-wrapped
# in a new gateway - which is desirable, as one gateway should only support
# one interface (this wont affect the users of this policy - we can have as many
# gateways as we like pointing to the same Python objects - the users never
# see what object the call came in from.
# NOTE: We could have simply returned the instance and let the framework
# do the auto-wrap for us - but this way we prevent a round-trip back into Python
# code just for the autowrap.
return xpcom.server.WrapObject(self._obj_, iid, bWrapClient = 0)
# Always support nsIClassInfo
if iid == _xpcom.IID_nsIClassInfo:
return GetClassInfoForObject(self._obj_)
# See if the instance has a QI
# use lower-case "_query_interface_" as win32com does, and it doesnt really matter.
delegate = getattr(self._obj_, "_query_interface_", None)
if delegate is not None:
# The COM object itself doesnt get passed to the child
# (again, as win32com doesnt). It is rarely needed
# (in win32com, we dont even pass it to the policy, although we have identified
# one place where we should - for marshalling - so I figured I may as well pass it
# to the policy layer here, but no all the way down to the object.
return delegate(iid)
# Finally see if we are being queried for one of the "nsISupports primitives"
if not _supports_primitives_map_:
iim = _xpcom.XPTI_GetInterfaceInfoManager()
for (iid_name, attr, cvt) in _supports_primitives_data_:
special_iid = iim.GetInfoForName(iid_name).GetIID()
_supports_primitives_map_[special_iid] = (attr, cvt)
attr, cvt = _supports_primitives_map_.get(iid, (None,None))
if attr is not None and hasattr(self._obj_, attr):
return xpcom.server.WrapObject(SupportsPrimitive(iid, self._obj_, attr, cvt), iid, bWrapClient = 0)
# Out of clever things to try!
return None # We dont support this IID.
def _MakeInterfaceParam_(self, interface, iid, method_index, mi, param_index):
# Wrap a "raw" interface object in a nice object. The result of this
# function will be passed to one of the gateway methods.
if iid is None:
# look up the interface info - this will be true for all xpcom called interfaces.
if self._interface_info_ is None:
import xpcom.xpt
self._interface_info_ = xpcom.xpt.Interface( self._iid_ )
iid = self._interface_iid_map_.get( (method_index, param_index))
if iid is None:
iid = self._interface_info_.GetIIDForParam(method_index, param_index)
self._interface_iid_map_[(method_index, param_index)] = iid
# handle nsIVariant
if iid == IID_nsIVariant:
interface = interface.QueryInterface(iid)
dt = interface.dataType
if dt in VARIANT_INT_TYPES:
return interface.getAsInt32()
if dt in VARIANT_LONG_TYPES:
return interface.getAsInt64()
if dt in VARIANT_FLOAT_TYPES:
return interface.getAsFloat()
if dt in VARIANT_STRING_TYPES:
return interface.getAsStringWithSize()
if dt in VARIANT_UNICODE_TYPES:
return interface.getAsWStringWithSize()
if dt == xpcom_consts.VTYPE_BOOL:
return interface.getAsBool()
if dt == xpcom_consts.VTYPE_INTERFACE:
return interface.getAsISupports()
if dt == xpcom_consts.VTYPE_INTERFACE_IS:
return interface.getAsInterface()
if dt == xpcom_consts.VTYPE_EMPTY or dt == xpcom_consts.VTYPE_VOID:
return None
if dt == xpcom_consts.VTYPE_ARRAY:
return interface.getAsArray()
if dt == xpcom_consts.VTYPE_EMPTY_ARRAY:
return []
if dt == xpcom_consts.VTYPE_ID:
return interface.getAsID()
# all else fails...
logger.warning("Warning: nsIVariant type %d not supported - returning a string", dt)
try:
return interface.getAsString()
except COMException:
logger.exception("Error: failed to get Variant as a string - returning variant object")
return interface
return client.Component(interface, iid)
def _CallMethod_(self, com_object, index, info, params):
#print "_CallMethod_", index, info, params
flags, name, param_descs, ret = info
assert ret[1][0] == xpcom_consts.TD_UINT32, "Expected an nsresult (%s)" % (ret,)
if XPT_MD_IS_GETTER(flags):
# Look for a function of that name
func = getattr(self._obj_, "get_" + name, None)
if func is None:
assert len(param_descs)==1 and len(params)==0, "Can only handle a single [out] arg for a default getter"
ret = getattr(self._obj_, name) # Let attribute error go here!
else:
ret = func(*params)
return 0, ret
elif XPT_MD_IS_SETTER(flags):
# Look for a function of that name
func = getattr(self._obj_, "set_" + name, None)
if func is None:
assert len(param_descs)==1 and len(params)==1, "Can only handle a single [in] arg for a default setter"
setattr(self._obj_, name, params[0]) # Let attribute error go here!
else:
func(*params)
return 0
else:
# A regular method.
func = getattr(self._obj_, name)
return 0, func(*params)
def _doHandleException(self, func_name, exc_info):
exc_val = exc_info[1]
is_server_exception = isinstance(exc_val, ServerException)
if is_server_exception:
# When a component raised an explicit COM exception, it is
# considered 'normal' - however, we still write a debug log
# record to help track these otherwise silent exceptions.
# Note that Python 2.3 does not allow an explicit exc_info tuple
# and passing 'True' will not work as there is no exception pending.
# Trick things!
if logger.isEnabledFor(logging.DEBUG):
try:
if sys.version_info[0] <= 2:
exec('raise exc_info[0], exc_info[1], exc_info[2]')
else:
raise exc_info[0](exc_info[1]).with_traceback(exc_info[2])
except:
logger.debug("'%s' raised COM Exception %s",
func_name, exc_val, exc_info = 1)
return exc_val.errno
# Unhandled exception - always print a warning and the traceback.
# As above, trick the logging module to handle Python 2.3
try:
if sys.version_info[0] <= 2:
exec('raise exc_info[0], exc_info[1], exc_info[2]')
else:
raise exc_info[0](exc_info[1]).with_traceback(exc_info[2])
except:
logger.exception("Unhandled exception calling '%s'", func_name)
return nsError.NS_ERROR_FAILURE
# Called whenever an unhandled Python exception is detected as a result
# of _CallMethod_ - this exception may have been raised during the _CallMethod_
# invocation, or after its return, but when unpacking the results
# eg, type errors, such as a Python integer being used as a string "out" param.
def _CallMethodException_(self, com_object, index, info, params, exc_info):
# Later we may want to have some smart "am I debugging" flags?
# Or maybe just delegate to the actual object - it's probably got the best
# idea what to do with them!
flags, name, param_descs, ret = info
exc_typ, exc_val, exc_tb = exc_info
# use the xpt module to get a better repr for the method.
# But if we fail, ignore it!
try:
import xpcom.xpt
m = xpcom.xpt.Method(info, index, None)
func_repr = m.Describe().lstrip()
except COMException:
func_repr = "%s(%r)" % (name, param_descs)
except:
# any other errors are evil!? Log it
self._doHandleException("<building method repr>", sys.exc_info())
# And fall through to logging the original error.
return self._doHandleException(func_repr, exc_info)
# Called whenever a gateway fails due to anything other than _CallMethod_.
# Really only used for the component loader etc objects, so most
# users should never see exceptions triggered here.
def _GatewayException_(self, name, exc_info):
return self._doHandleException(name, exc_info)
if sys.version_info[0] <= 2:
_supports_primitives_data_ = [
("nsISupportsCString", "__str__", str),
("nsISupportsString", "__unicode__", unicode),
("nsISupportsPRUint64", "__long__", long),
("nsISupportsPRInt64", "__long__", long),
("nsISupportsPRUint32", "__int__", int),
("nsISupportsPRInt32", "__int__", int),
("nsISupportsPRUint16", "__int__", int),
("nsISupportsPRInt16", "__int__", int),
("nsISupportsPRUint8", "__int__", int),
("nsISupportsPRBool", "__nonzero__", operator.truth),
("nsISupportsDouble", "__float__", float),
("nsISupportsFloat", "__float__", float),
]
else:
_supports_primitives_data_ = [
("nsISupportsCString", "__str__", str),
("nsISupportsString", "__unicode__", str),
("nsISupportsPRUint64", "__long__", int),
("nsISupportsPRInt64", "__long__", int),
("nsISupportsPRUint32", "__int__", int),
("nsISupportsPRInt32", "__int__", int),
("nsISupportsPRUint16", "__int__", int),
("nsISupportsPRInt16", "__int__", int),
("nsISupportsPRUint8", "__int__", int),
("nsISupportsPRBool", "__nonzero__", operator.truth),
("nsISupportsDouble", "__float__", float),
("nsISupportsFloat", "__float__", float),
]
# Support for the nsISupports primitives:
class SupportsPrimitive:
_com_interfaces_ = ["nsISupports"]
def __init__(self, iid, base_ob, attr_name, converter):
self.iid = iid
self.base_ob = base_ob
self.attr_name = attr_name
self.converter = converter
def _query_interface_(self, iid):
if iid == self.iid:
return 1
return None
def get_data(self):
method = getattr(self.base_ob, self.attr_name)
val = method()
return self.converter(val)
def set_data(self, val):
raise ServerException(nsError.NS_ERROR_NOT_IMPLEMENTED)
def toString(self):
return str(self.get_data())
def _shutdown():
class_info_cache.clear()
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