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	 1e197e63e2
			
		
	
	
		1e197e63e2
		
			
		
	
	
	
	
		
			
			* Adds EXIT_INTERPRETER instruction to exit PyEval_EvalDefault() * Simplifies RETURN_VALUE, YIELD_VALUE and RETURN_GENERATOR instructions as they no longer need to check for entry frames.
		
			
				
	
	
		
			2124 lines
		
	
	
	
		
			69 KiB
		
	
	
	
		
			Python
		
	
	
		
			Executable file
		
	
	
	
	
			
		
		
	
	
			2124 lines
		
	
	
	
		
			69 KiB
		
	
	
	
		
			Python
		
	
	
		
			Executable file
		
	
	
	
	
| #!/usr/bin/python
 | |
| '''
 | |
| From gdb 7 onwards, gdb's build can be configured --with-python, allowing gdb
 | |
| to be extended with Python code e.g. for library-specific data visualizations,
 | |
| such as for the C++ STL types.  Documentation on this API can be seen at:
 | |
| http://sourceware.org/gdb/current/onlinedocs/gdb/Python-API.html
 | |
| 
 | |
| 
 | |
| This python module deals with the case when the process being debugged (the
 | |
| "inferior process" in gdb parlance) is itself python, or more specifically,
 | |
| linked against libpython.  In this situation, almost every item of data is a
 | |
| (PyObject*), and having the debugger merely print their addresses is not very
 | |
| enlightening.
 | |
| 
 | |
| This module embeds knowledge about the implementation details of libpython so
 | |
| that we can emit useful visualizations e.g. a string, a list, a dict, a frame
 | |
| giving file/line information and the state of local variables
 | |
| 
 | |
| In particular, given a gdb.Value corresponding to a PyObject* in the inferior
 | |
| process, we can generate a "proxy value" within the gdb process.  For example,
 | |
| given a PyObject* in the inferior process that is in fact a PyListObject*
 | |
| holding three PyObject* that turn out to be PyBytesObject* instances, we can
 | |
| generate a proxy value within the gdb process that is a list of bytes
 | |
| instances:
 | |
|   [b"foo", b"bar", b"baz"]
 | |
| 
 | |
| Doing so can be expensive for complicated graphs of objects, and could take
 | |
| some time, so we also have a "write_repr" method that writes a representation
 | |
| of the data to a file-like object.  This allows us to stop the traversal by
 | |
| having the file-like object raise an exception if it gets too much data.
 | |
| 
 | |
| With both "proxyval" and "write_repr" we keep track of the set of all addresses
 | |
| visited so far in the traversal, to avoid infinite recursion due to cycles in
 | |
| the graph of object references.
 | |
| 
 | |
| We try to defer gdb.lookup_type() invocations for python types until as late as
 | |
| possible: for a dynamically linked python binary, when the process starts in
 | |
| the debugger, the libpython.so hasn't been dynamically loaded yet, so none of
 | |
| the type names are known to the debugger
 | |
| 
 | |
| The module also extends gdb with some python-specific commands.
 | |
| '''
 | |
| 
 | |
| import gdb
 | |
| import os
 | |
| import locale
 | |
| import sys
 | |
| 
 | |
| 
 | |
| # Look up the gdb.Type for some standard types:
 | |
| # Those need to be refreshed as types (pointer sizes) may change when
 | |
| # gdb loads different executables
 | |
| 
 | |
| def _type_char_ptr():
 | |
|     return gdb.lookup_type('char').pointer()  # char*
 | |
| 
 | |
| 
 | |
| def _type_unsigned_char_ptr():
 | |
|     return gdb.lookup_type('unsigned char').pointer()  # unsigned char*
 | |
| 
 | |
| 
 | |
| def _type_unsigned_short_ptr():
 | |
|     return gdb.lookup_type('unsigned short').pointer()
 | |
| 
 | |
| 
 | |
| def _type_unsigned_int_ptr():
 | |
|     return gdb.lookup_type('unsigned int').pointer()
 | |
| 
 | |
| 
 | |
| def _sizeof_void_p():
 | |
|     return gdb.lookup_type('void').pointer().sizeof
 | |
| 
 | |
| 
 | |
| Py_TPFLAGS_MANAGED_DICT      = (1 << 4)
 | |
| Py_TPFLAGS_HEAPTYPE          = (1 << 9)
 | |
| Py_TPFLAGS_LONG_SUBCLASS     = (1 << 24)
 | |
| Py_TPFLAGS_LIST_SUBCLASS     = (1 << 25)
 | |
| Py_TPFLAGS_TUPLE_SUBCLASS    = (1 << 26)
 | |
| Py_TPFLAGS_BYTES_SUBCLASS    = (1 << 27)
 | |
| Py_TPFLAGS_UNICODE_SUBCLASS  = (1 << 28)
 | |
| Py_TPFLAGS_DICT_SUBCLASS     = (1 << 29)
 | |
| Py_TPFLAGS_BASE_EXC_SUBCLASS = (1 << 30)
 | |
| Py_TPFLAGS_TYPE_SUBCLASS     = (1 << 31)
 | |
| 
 | |
| #From pycore_frame.h
 | |
| FRAME_OWNED_BY_CSTACK = 3
 | |
| 
 | |
| MAX_OUTPUT_LEN=1024
 | |
| 
 | |
| hexdigits = "0123456789abcdef"
 | |
| 
 | |
| ENCODING = locale.getpreferredencoding()
 | |
| 
 | |
| FRAME_INFO_OPTIMIZED_OUT = '(frame information optimized out)'
 | |
| UNABLE_READ_INFO_PYTHON_FRAME = 'Unable to read information on python frame'
 | |
| EVALFRAME = '_PyEval_EvalFrameDefault'
 | |
| 
 | |
| class NullPyObjectPtr(RuntimeError):
 | |
|     pass
 | |
| 
 | |
| 
 | |
| def safety_limit(val):
 | |
|     # Given an integer value from the process being debugged, limit it to some
 | |
|     # safety threshold so that arbitrary breakage within said process doesn't
 | |
|     # break the gdb process too much (e.g. sizes of iterations, sizes of lists)
 | |
|     return min(val, 1000)
 | |
| 
 | |
| 
 | |
| def safe_range(val):
 | |
|     # As per range, but don't trust the value too much: cap it to a safety
 | |
|     # threshold in case the data was corrupted
 | |
|     return range(safety_limit(int(val)))
 | |
| 
 | |
| try:
 | |
|     os_fsencode = os.fsencode
 | |
| except AttributeError:
 | |
|     def os_fsencode(filename):
 | |
|         if not isinstance(filename, unicode):
 | |
|             return filename
 | |
|         encoding = sys.getfilesystemencoding()
 | |
|         if encoding == 'mbcs':
 | |
|             # mbcs doesn't support surrogateescape
 | |
|             return filename.encode(encoding)
 | |
|         encoded = []
 | |
|         for char in filename:
 | |
|             # surrogateescape error handler
 | |
|             if 0xDC80 <= ord(char) <= 0xDCFF:
 | |
|                 byte = chr(ord(char) - 0xDC00)
 | |
|             else:
 | |
|                 byte = char.encode(encoding)
 | |
|             encoded.append(byte)
 | |
|         return ''.join(encoded)
 | |
| 
 | |
| class StringTruncated(RuntimeError):
 | |
|     pass
 | |
| 
 | |
| class TruncatedStringIO(object):
 | |
|     '''Similar to io.StringIO, but can truncate the output by raising a
 | |
|     StringTruncated exception'''
 | |
|     def __init__(self, maxlen=None):
 | |
|         self._val = ''
 | |
|         self.maxlen = maxlen
 | |
| 
 | |
|     def write(self, data):
 | |
|         if self.maxlen:
 | |
|             if len(data) + len(self._val) > self.maxlen:
 | |
|                 # Truncation:
 | |
|                 self._val += data[0:self.maxlen - len(self._val)]
 | |
|                 raise StringTruncated()
 | |
| 
 | |
|         self._val += data
 | |
| 
 | |
|     def getvalue(self):
 | |
|         return self._val
 | |
| 
 | |
| class PyObjectPtr(object):
 | |
|     """
 | |
|     Class wrapping a gdb.Value that's either a (PyObject*) within the
 | |
|     inferior process, or some subclass pointer e.g. (PyBytesObject*)
 | |
| 
 | |
|     There will be a subclass for every refined PyObject type that we care
 | |
|     about.
 | |
| 
 | |
|     Note that at every stage the underlying pointer could be NULL, point
 | |
|     to corrupt data, etc; this is the debugger, after all.
 | |
|     """
 | |
|     _typename = 'PyObject'
 | |
| 
 | |
|     def __init__(self, gdbval, cast_to=None):
 | |
|         if cast_to:
 | |
|             self._gdbval = gdbval.cast(cast_to)
 | |
|         else:
 | |
|             self._gdbval = gdbval
 | |
| 
 | |
|     def field(self, name):
 | |
|         '''
 | |
|         Get the gdb.Value for the given field within the PyObject, coping with
 | |
|         some python 2 versus python 3 differences.
 | |
| 
 | |
|         Various libpython types are defined using the "PyObject_HEAD" and
 | |
|         "PyObject_VAR_HEAD" macros.
 | |
| 
 | |
|         In Python 2, this these are defined so that "ob_type" and (for a var
 | |
|         object) "ob_size" are fields of the type in question.
 | |
| 
 | |
|         In Python 3, this is defined as an embedded PyVarObject type thus:
 | |
|            PyVarObject ob_base;
 | |
|         so that the "ob_size" field is located insize the "ob_base" field, and
 | |
|         the "ob_type" is most easily accessed by casting back to a (PyObject*).
 | |
|         '''
 | |
|         if self.is_null():
 | |
|             raise NullPyObjectPtr(self)
 | |
| 
 | |
|         if name == 'ob_type':
 | |
|             pyo_ptr = self._gdbval.cast(PyObjectPtr.get_gdb_type())
 | |
|             return pyo_ptr.dereference()[name]
 | |
| 
 | |
|         if name == 'ob_size':
 | |
|             pyo_ptr = self._gdbval.cast(PyVarObjectPtr.get_gdb_type())
 | |
|             return pyo_ptr.dereference()[name]
 | |
| 
 | |
|         # General case: look it up inside the object:
 | |
|         return self._gdbval.dereference()[name]
 | |
| 
 | |
|     def pyop_field(self, name):
 | |
|         '''
 | |
|         Get a PyObjectPtr for the given PyObject* field within this PyObject,
 | |
|         coping with some python 2 versus python 3 differences.
 | |
|         '''
 | |
|         return PyObjectPtr.from_pyobject_ptr(self.field(name))
 | |
| 
 | |
|     def write_field_repr(self, name, out, visited):
 | |
|         '''
 | |
|         Extract the PyObject* field named "name", and write its representation
 | |
|         to file-like object "out"
 | |
|         '''
 | |
|         field_obj = self.pyop_field(name)
 | |
|         field_obj.write_repr(out, visited)
 | |
| 
 | |
|     def get_truncated_repr(self, maxlen):
 | |
|         '''
 | |
|         Get a repr-like string for the data, but truncate it at "maxlen" bytes
 | |
|         (ending the object graph traversal as soon as you do)
 | |
|         '''
 | |
|         out = TruncatedStringIO(maxlen)
 | |
|         try:
 | |
|             self.write_repr(out, set())
 | |
|         except StringTruncated:
 | |
|             # Truncation occurred:
 | |
|             return out.getvalue() + '...(truncated)'
 | |
| 
 | |
|         # No truncation occurred:
 | |
|         return out.getvalue()
 | |
| 
 | |
|     def type(self):
 | |
|         return PyTypeObjectPtr(self.field('ob_type'))
 | |
| 
 | |
|     def is_null(self):
 | |
|         return 0 == int(self._gdbval)
 | |
| 
 | |
|     def is_optimized_out(self):
 | |
|         '''
 | |
|         Is the value of the underlying PyObject* visible to the debugger?
 | |
| 
 | |
|         This can vary with the precise version of the compiler used to build
 | |
|         Python, and the precise version of gdb.
 | |
| 
 | |
|         See e.g. https://bugzilla.redhat.com/show_bug.cgi?id=556975 with
 | |
|         PyEval_EvalFrameEx's "f"
 | |
|         '''
 | |
|         return self._gdbval.is_optimized_out
 | |
| 
 | |
|     def safe_tp_name(self):
 | |
|         try:
 | |
|             ob_type = self.type()
 | |
|             tp_name = ob_type.field('tp_name')
 | |
|             return tp_name.string()
 | |
|         # NullPyObjectPtr: NULL tp_name?
 | |
|         # RuntimeError: Can't even read the object at all?
 | |
|         # UnicodeDecodeError: Failed to decode tp_name bytestring
 | |
|         except (NullPyObjectPtr, RuntimeError, UnicodeDecodeError):
 | |
|             return 'unknown'
 | |
| 
 | |
|     def proxyval(self, visited):
 | |
|         '''
 | |
|         Scrape a value from the inferior process, and try to represent it
 | |
|         within the gdb process, whilst (hopefully) avoiding crashes when
 | |
|         the remote data is corrupt.
 | |
| 
 | |
|         Derived classes will override this.
 | |
| 
 | |
|         For example, a PyIntObject* with ob_ival 42 in the inferior process
 | |
|         should result in an int(42) in this process.
 | |
| 
 | |
|         visited: a set of all gdb.Value pyobject pointers already visited
 | |
|         whilst generating this value (to guard against infinite recursion when
 | |
|         visiting object graphs with loops).  Analogous to Py_ReprEnter and
 | |
|         Py_ReprLeave
 | |
|         '''
 | |
| 
 | |
|         class FakeRepr(object):
 | |
|             """
 | |
|             Class representing a non-descript PyObject* value in the inferior
 | |
|             process for when we don't have a custom scraper, intended to have
 | |
|             a sane repr().
 | |
|             """
 | |
| 
 | |
|             def __init__(self, tp_name, address):
 | |
|                 self.tp_name = tp_name
 | |
|                 self.address = address
 | |
| 
 | |
|             def __repr__(self):
 | |
|                 # For the NULL pointer, we have no way of knowing a type, so
 | |
|                 # special-case it as per
 | |
|                 # http://bugs.python.org/issue8032#msg100882
 | |
|                 if self.address == 0:
 | |
|                     return '0x0'
 | |
|                 return '<%s at remote 0x%x>' % (self.tp_name, self.address)
 | |
| 
 | |
|         return FakeRepr(self.safe_tp_name(),
 | |
|                         int(self._gdbval))
 | |
| 
 | |
|     def write_repr(self, out, visited):
 | |
|         '''
 | |
|         Write a string representation of the value scraped from the inferior
 | |
|         process to "out", a file-like object.
 | |
|         '''
 | |
|         # Default implementation: generate a proxy value and write its repr
 | |
|         # However, this could involve a lot of work for complicated objects,
 | |
|         # so for derived classes we specialize this
 | |
|         return out.write(repr(self.proxyval(visited)))
 | |
| 
 | |
|     @classmethod
 | |
|     def subclass_from_type(cls, t):
 | |
|         '''
 | |
|         Given a PyTypeObjectPtr instance wrapping a gdb.Value that's a
 | |
|         (PyTypeObject*), determine the corresponding subclass of PyObjectPtr
 | |
|         to use
 | |
| 
 | |
|         Ideally, we would look up the symbols for the global types, but that
 | |
|         isn't working yet:
 | |
|           (gdb) python print gdb.lookup_symbol('PyList_Type')[0].value
 | |
|           Traceback (most recent call last):
 | |
|             File "<string>", line 1, in <module>
 | |
|           NotImplementedError: Symbol type not yet supported in Python scripts.
 | |
|           Error while executing Python code.
 | |
| 
 | |
|         For now, we use tp_flags, after doing some string comparisons on the
 | |
|         tp_name for some special-cases that don't seem to be visible through
 | |
|         flags
 | |
|         '''
 | |
|         try:
 | |
|             tp_name = t.field('tp_name').string()
 | |
|             tp_flags = int(t.field('tp_flags'))
 | |
|         # RuntimeError: NULL pointers
 | |
|         # UnicodeDecodeError: string() fails to decode the bytestring
 | |
|         except (RuntimeError, UnicodeDecodeError):
 | |
|             # Handle any kind of error e.g. NULL ptrs by simply using the base
 | |
|             # class
 | |
|             return cls
 | |
| 
 | |
|         #print('tp_flags = 0x%08x' % tp_flags)
 | |
|         #print('tp_name = %r' % tp_name)
 | |
| 
 | |
|         name_map = {'bool': PyBoolObjectPtr,
 | |
|                     'classobj': PyClassObjectPtr,
 | |
|                     'NoneType': PyNoneStructPtr,
 | |
|                     'frame': PyFrameObjectPtr,
 | |
|                     'set' : PySetObjectPtr,
 | |
|                     'frozenset' : PySetObjectPtr,
 | |
|                     'builtin_function_or_method' : PyCFunctionObjectPtr,
 | |
|                     'method-wrapper': wrapperobject,
 | |
|                     }
 | |
|         if tp_name in name_map:
 | |
|             return name_map[tp_name]
 | |
| 
 | |
|         if tp_flags & Py_TPFLAGS_HEAPTYPE:
 | |
|             return HeapTypeObjectPtr
 | |
| 
 | |
|         if tp_flags & Py_TPFLAGS_LONG_SUBCLASS:
 | |
|             return PyLongObjectPtr
 | |
|         if tp_flags & Py_TPFLAGS_LIST_SUBCLASS:
 | |
|             return PyListObjectPtr
 | |
|         if tp_flags & Py_TPFLAGS_TUPLE_SUBCLASS:
 | |
|             return PyTupleObjectPtr
 | |
|         if tp_flags & Py_TPFLAGS_BYTES_SUBCLASS:
 | |
|             return PyBytesObjectPtr
 | |
|         if tp_flags & Py_TPFLAGS_UNICODE_SUBCLASS:
 | |
|             return PyUnicodeObjectPtr
 | |
|         if tp_flags & Py_TPFLAGS_DICT_SUBCLASS:
 | |
|             return PyDictObjectPtr
 | |
|         if tp_flags & Py_TPFLAGS_BASE_EXC_SUBCLASS:
 | |
|             return PyBaseExceptionObjectPtr
 | |
|         #if tp_flags & Py_TPFLAGS_TYPE_SUBCLASS:
 | |
|         #    return PyTypeObjectPtr
 | |
| 
 | |
|         # Use the base class:
 | |
|         return cls
 | |
| 
 | |
|     @classmethod
 | |
|     def from_pyobject_ptr(cls, gdbval):
 | |
|         '''
 | |
|         Try to locate the appropriate derived class dynamically, and cast
 | |
|         the pointer accordingly.
 | |
|         '''
 | |
|         try:
 | |
|             p = PyObjectPtr(gdbval)
 | |
|             cls = cls.subclass_from_type(p.type())
 | |
|             return cls(gdbval, cast_to=cls.get_gdb_type())
 | |
|         except RuntimeError:
 | |
|             # Handle any kind of error e.g. NULL ptrs by simply using the base
 | |
|             # class
 | |
|             pass
 | |
|         return cls(gdbval)
 | |
| 
 | |
|     @classmethod
 | |
|     def get_gdb_type(cls):
 | |
|         return gdb.lookup_type(cls._typename).pointer()
 | |
| 
 | |
|     def as_address(self):
 | |
|         return int(self._gdbval)
 | |
| 
 | |
| class PyVarObjectPtr(PyObjectPtr):
 | |
|     _typename = 'PyVarObject'
 | |
| 
 | |
| class ProxyAlreadyVisited(object):
 | |
|     '''
 | |
|     Placeholder proxy to use when protecting against infinite recursion due to
 | |
|     loops in the object graph.
 | |
| 
 | |
|     Analogous to the values emitted by the users of Py_ReprEnter and Py_ReprLeave
 | |
|     '''
 | |
|     def __init__(self, rep):
 | |
|         self._rep = rep
 | |
| 
 | |
|     def __repr__(self):
 | |
|         return self._rep
 | |
| 
 | |
| 
 | |
| def _write_instance_repr(out, visited, name, pyop_attrdict, address):
 | |
|     '''Shared code for use by all classes:
 | |
|     write a representation to file-like object "out"'''
 | |
|     out.write('<')
 | |
|     out.write(name)
 | |
| 
 | |
|     # Write dictionary of instance attributes:
 | |
|     if isinstance(pyop_attrdict, (PyKeysValuesPair, PyDictObjectPtr)):
 | |
|         out.write('(')
 | |
|         first = True
 | |
|         items = pyop_attrdict.iteritems()
 | |
|         for pyop_arg, pyop_val in items:
 | |
|             if not first:
 | |
|                 out.write(', ')
 | |
|             first = False
 | |
|             out.write(pyop_arg.proxyval(visited))
 | |
|             out.write('=')
 | |
|             pyop_val.write_repr(out, visited)
 | |
|         out.write(')')
 | |
|     out.write(' at remote 0x%x>' % address)
 | |
| 
 | |
| 
 | |
| class InstanceProxy(object):
 | |
| 
 | |
|     def __init__(self, cl_name, attrdict, address):
 | |
|         self.cl_name = cl_name
 | |
|         self.attrdict = attrdict
 | |
|         self.address = address
 | |
| 
 | |
|     def __repr__(self):
 | |
|         if isinstance(self.attrdict, dict):
 | |
|             kwargs = ', '.join(["%s=%r" % (arg, val)
 | |
|                                 for arg, val in self.attrdict.items()])
 | |
|             return '<%s(%s) at remote 0x%x>' % (self.cl_name,
 | |
|                                                 kwargs, self.address)
 | |
|         else:
 | |
|             return '<%s at remote 0x%x>' % (self.cl_name,
 | |
|                                             self.address)
 | |
| 
 | |
| def _PyObject_VAR_SIZE(typeobj, nitems):
 | |
|     if _PyObject_VAR_SIZE._type_size_t is None:
 | |
|         _PyObject_VAR_SIZE._type_size_t = gdb.lookup_type('size_t')
 | |
| 
 | |
|     return ( ( typeobj.field('tp_basicsize') +
 | |
|                nitems * typeobj.field('tp_itemsize') +
 | |
|                (_sizeof_void_p() - 1)
 | |
|              ) & ~(_sizeof_void_p() - 1)
 | |
|            ).cast(_PyObject_VAR_SIZE._type_size_t)
 | |
| _PyObject_VAR_SIZE._type_size_t = None
 | |
| 
 | |
| class HeapTypeObjectPtr(PyObjectPtr):
 | |
|     _typename = 'PyObject'
 | |
| 
 | |
|     def get_attr_dict(self):
 | |
|         '''
 | |
|         Get the PyDictObject ptr representing the attribute dictionary
 | |
|         (or None if there's a problem)
 | |
|         '''
 | |
|         try:
 | |
|             typeobj = self.type()
 | |
|             dictoffset = int_from_int(typeobj.field('tp_dictoffset'))
 | |
|             if dictoffset != 0:
 | |
|                 if dictoffset < 0:
 | |
|                     if int_from_int(typeobj.field('tp_flags')) & Py_TPFLAGS_MANAGED_DICT:
 | |
|                         assert dictoffset == -1
 | |
|                         dictoffset = -3 * _sizeof_void_p()
 | |
|                     else:
 | |
|                         type_PyVarObject_ptr = gdb.lookup_type('PyVarObject').pointer()
 | |
|                         tsize = int_from_int(self._gdbval.cast(type_PyVarObject_ptr)['ob_size'])
 | |
|                         if tsize < 0:
 | |
|                             tsize = -tsize
 | |
|                         size = _PyObject_VAR_SIZE(typeobj, tsize)
 | |
|                         dictoffset += size
 | |
|                         assert dictoffset % _sizeof_void_p() == 0
 | |
| 
 | |
|                 dictptr = self._gdbval.cast(_type_char_ptr()) + dictoffset
 | |
|                 PyObjectPtrPtr = PyObjectPtr.get_gdb_type().pointer()
 | |
|                 dictptr = dictptr.cast(PyObjectPtrPtr)
 | |
|                 if int(dictptr.dereference()) & 1:
 | |
|                     return None
 | |
|                 return PyObjectPtr.from_pyobject_ptr(dictptr.dereference())
 | |
|         except RuntimeError:
 | |
|             # Corrupt data somewhere; fail safe
 | |
|             pass
 | |
| 
 | |
|         # Not found, or some kind of error:
 | |
|         return None
 | |
| 
 | |
|     def get_keys_values(self):
 | |
|         typeobj = self.type()
 | |
|         has_values =  int_from_int(typeobj.field('tp_flags')) & Py_TPFLAGS_MANAGED_DICT
 | |
|         if not has_values:
 | |
|             return None
 | |
|         charptrptr_t = _type_char_ptr().pointer()
 | |
|         ptr = self._gdbval.cast(charptrptr_t) - 3
 | |
|         char_ptr = ptr.dereference()
 | |
|         if (int(char_ptr) & 1) == 0:
 | |
|             return None
 | |
|         char_ptr += 1
 | |
|         values_ptr = char_ptr.cast(gdb.lookup_type("PyDictValues").pointer())
 | |
|         values = values_ptr['values']
 | |
|         return PyKeysValuesPair(self.get_cached_keys(), values)
 | |
| 
 | |
|     def get_cached_keys(self):
 | |
|         typeobj = self.type()
 | |
|         HeapTypePtr = gdb.lookup_type("PyHeapTypeObject").pointer()
 | |
|         return typeobj._gdbval.cast(HeapTypePtr)['ht_cached_keys']
 | |
| 
 | |
|     def proxyval(self, visited):
 | |
|         '''
 | |
|         Support for classes.
 | |
| 
 | |
|         Currently we just locate the dictionary using a transliteration to
 | |
|         python of _PyObject_GetDictPtr, ignoring descriptors
 | |
|         '''
 | |
|         # Guard against infinite loops:
 | |
|         if self.as_address() in visited:
 | |
|             return ProxyAlreadyVisited('<...>')
 | |
|         visited.add(self.as_address())
 | |
| 
 | |
|         keys_values = self.get_keys_values()
 | |
|         if keys_values:
 | |
|             attr_dict = keys_values.proxyval(visited)
 | |
|         else:
 | |
|             pyop_attr_dict = self.get_attr_dict()
 | |
|             if pyop_attr_dict:
 | |
|                 attr_dict = pyop_attr_dict.proxyval(visited)
 | |
|             else:
 | |
|                 attr_dict = {}
 | |
|         tp_name = self.safe_tp_name()
 | |
| 
 | |
|         # Class:
 | |
|         return InstanceProxy(tp_name, attr_dict, int(self._gdbval))
 | |
| 
 | |
|     def write_repr(self, out, visited):
 | |
|         # Guard against infinite loops:
 | |
|         if self.as_address() in visited:
 | |
|             out.write('<...>')
 | |
|             return
 | |
|         visited.add(self.as_address())
 | |
| 
 | |
|         pyop_attrs = self.get_keys_values()
 | |
|         if not pyop_attrs:
 | |
|             pyop_attrs = self.get_attr_dict()
 | |
|         _write_instance_repr(out, visited,
 | |
|                              self.safe_tp_name(), pyop_attrs, self.as_address())
 | |
| 
 | |
| class ProxyException(Exception):
 | |
|     def __init__(self, tp_name, args):
 | |
|         self.tp_name = tp_name
 | |
|         self.args = args
 | |
| 
 | |
|     def __repr__(self):
 | |
|         return '%s%r' % (self.tp_name, self.args)
 | |
| 
 | |
| class PyBaseExceptionObjectPtr(PyObjectPtr):
 | |
|     """
 | |
|     Class wrapping a gdb.Value that's a PyBaseExceptionObject* i.e. an exception
 | |
|     within the process being debugged.
 | |
|     """
 | |
|     _typename = 'PyBaseExceptionObject'
 | |
| 
 | |
|     def proxyval(self, visited):
 | |
|         # Guard against infinite loops:
 | |
|         if self.as_address() in visited:
 | |
|             return ProxyAlreadyVisited('(...)')
 | |
|         visited.add(self.as_address())
 | |
|         arg_proxy = self.pyop_field('args').proxyval(visited)
 | |
|         return ProxyException(self.safe_tp_name(),
 | |
|                               arg_proxy)
 | |
| 
 | |
|     def write_repr(self, out, visited):
 | |
|         # Guard against infinite loops:
 | |
|         if self.as_address() in visited:
 | |
|             out.write('(...)')
 | |
|             return
 | |
|         visited.add(self.as_address())
 | |
| 
 | |
|         out.write(self.safe_tp_name())
 | |
|         self.write_field_repr('args', out, visited)
 | |
| 
 | |
| class PyClassObjectPtr(PyObjectPtr):
 | |
|     """
 | |
|     Class wrapping a gdb.Value that's a PyClassObject* i.e. a <classobj>
 | |
|     instance within the process being debugged.
 | |
|     """
 | |
|     _typename = 'PyClassObject'
 | |
| 
 | |
| 
 | |
| class BuiltInFunctionProxy(object):
 | |
|     def __init__(self, ml_name):
 | |
|         self.ml_name = ml_name
 | |
| 
 | |
|     def __repr__(self):
 | |
|         return "<built-in function %s>" % self.ml_name
 | |
| 
 | |
| class BuiltInMethodProxy(object):
 | |
|     def __init__(self, ml_name, pyop_m_self):
 | |
|         self.ml_name = ml_name
 | |
|         self.pyop_m_self = pyop_m_self
 | |
| 
 | |
|     def __repr__(self):
 | |
|         return ('<built-in method %s of %s object at remote 0x%x>'
 | |
|                 % (self.ml_name,
 | |
|                    self.pyop_m_self.safe_tp_name(),
 | |
|                    self.pyop_m_self.as_address())
 | |
|                 )
 | |
| 
 | |
| class PyCFunctionObjectPtr(PyObjectPtr):
 | |
|     """
 | |
|     Class wrapping a gdb.Value that's a PyCFunctionObject*
 | |
|     (see Include/methodobject.h and Objects/methodobject.c)
 | |
|     """
 | |
|     _typename = 'PyCFunctionObject'
 | |
| 
 | |
|     def proxyval(self, visited):
 | |
|         m_ml = self.field('m_ml') # m_ml is a (PyMethodDef*)
 | |
|         try:
 | |
|             ml_name = m_ml['ml_name'].string()
 | |
|         except UnicodeDecodeError:
 | |
|             ml_name = '<ml_name:UnicodeDecodeError>'
 | |
| 
 | |
|         pyop_m_self = self.pyop_field('m_self')
 | |
|         if pyop_m_self.is_null():
 | |
|             return BuiltInFunctionProxy(ml_name)
 | |
|         else:
 | |
|             return BuiltInMethodProxy(ml_name, pyop_m_self)
 | |
| 
 | |
| # Python implementation of location table parsing algorithm
 | |
| def read(it):
 | |
|     return ord(next(it))
 | |
| 
 | |
| def read_varint(it):
 | |
|     b = read(it)
 | |
|     val = b & 63;
 | |
|     shift = 0;
 | |
|     while b & 64:
 | |
|         b = read(it)
 | |
|         shift += 6
 | |
|         val |= (b&63) << shift
 | |
|     return val
 | |
| 
 | |
| def read_signed_varint(it):
 | |
|     uval = read_varint(it)
 | |
|     if uval & 1:
 | |
|         return -(uval >> 1)
 | |
|     else:
 | |
|         return uval >> 1
 | |
| 
 | |
| def parse_location_table(firstlineno, linetable):
 | |
|     line = firstlineno
 | |
|     addr = 0
 | |
|     it = iter(linetable)
 | |
|     while True:
 | |
|         try:
 | |
|             first_byte = read(it)
 | |
|         except StopIteration:
 | |
|             return
 | |
|         code = (first_byte >> 3) & 15
 | |
|         length = (first_byte & 7) + 1
 | |
|         end_addr = addr + length
 | |
|         if code == 15:
 | |
|             yield addr, end_addr, None
 | |
|             addr = end_addr
 | |
|             continue
 | |
|         elif code == 14: # Long form
 | |
|             line_delta = read_signed_varint(it)
 | |
|             line += line_delta
 | |
|             end_line = line + read_varint(it)
 | |
|             col = read_varint(it)
 | |
|             end_col = read_varint(it)
 | |
|         elif code == 13: # No column
 | |
|             line_delta = read_signed_varint(it)
 | |
|             line += line_delta
 | |
|         elif code in (10, 11, 12): # new line
 | |
|             line_delta = code - 10
 | |
|             line += line_delta
 | |
|             column = read(it)
 | |
|             end_column = read(it)
 | |
|         else:
 | |
|             assert (0 <= code < 10)
 | |
|             second_byte = read(it)
 | |
|             column = code << 3 | (second_byte >> 4)
 | |
|         yield addr, end_addr, line
 | |
|         addr = end_addr
 | |
| 
 | |
| class PyCodeObjectPtr(PyObjectPtr):
 | |
|     """
 | |
|     Class wrapping a gdb.Value that's a PyCodeObject* i.e. a <code> instance
 | |
|     within the process being debugged.
 | |
|     """
 | |
|     _typename = 'PyCodeObject'
 | |
| 
 | |
|     def addr2line(self, addrq):
 | |
|         '''
 | |
|         Get the line number for a given bytecode offset
 | |
| 
 | |
|         Analogous to PyCode_Addr2Line; translated from pseudocode in
 | |
|         Objects/lnotab_notes.txt
 | |
|         '''
 | |
|         co_linetable = self.pyop_field('co_linetable').proxyval(set())
 | |
| 
 | |
|         # Initialize lineno to co_firstlineno as per PyCode_Addr2Line
 | |
|         # not 0, as lnotab_notes.txt has it:
 | |
|         lineno = int_from_int(self.field('co_firstlineno'))
 | |
| 
 | |
|         if addrq < 0:
 | |
|             return lineno
 | |
|         addr = 0
 | |
|         for addr, end_addr, line in parse_location_table(lineno, co_linetable):
 | |
|             if addr <= addrq and end_addr > addrq:
 | |
|                 return line
 | |
|         assert False, "Unreachable"
 | |
| 
 | |
| 
 | |
| def items_from_keys_and_values(keys, values):
 | |
|     entries, nentries = PyDictObjectPtr._get_entries(keys)
 | |
|     for i in safe_range(nentries):
 | |
|         ep = entries[i]
 | |
|         pyop_value = PyObjectPtr.from_pyobject_ptr(values[i])
 | |
|         if not pyop_value.is_null():
 | |
|             pyop_key = PyObjectPtr.from_pyobject_ptr(ep['me_key'])
 | |
|             yield (pyop_key, pyop_value)
 | |
| 
 | |
| class PyKeysValuesPair:
 | |
| 
 | |
|     def __init__(self, keys, values):
 | |
|         self.keys = keys
 | |
|         self.values = values
 | |
| 
 | |
|     def iteritems(self):
 | |
|         return items_from_keys_and_values(self.keys, self.values)
 | |
| 
 | |
|     def proxyval(self, visited):
 | |
|         result = {}
 | |
|         for pyop_key, pyop_value in self.iteritems():
 | |
|             proxy_key = pyop_key.proxyval(visited)
 | |
|             proxy_value = pyop_value.proxyval(visited)
 | |
|             result[proxy_key] = proxy_value
 | |
|         return result
 | |
| 
 | |
| class PyDictObjectPtr(PyObjectPtr):
 | |
|     """
 | |
|     Class wrapping a gdb.Value that's a PyDictObject* i.e. a dict instance
 | |
|     within the process being debugged.
 | |
|     """
 | |
|     _typename = 'PyDictObject'
 | |
| 
 | |
|     def iteritems(self):
 | |
|         '''
 | |
|         Yields a sequence of (PyObjectPtr key, PyObjectPtr value) pairs,
 | |
|         analogous to dict.iteritems()
 | |
|         '''
 | |
|         keys = self.field('ma_keys')
 | |
|         values = self.field('ma_values')
 | |
|         has_values = int(values)
 | |
|         if has_values:
 | |
|             values = values['values']
 | |
|         if has_values:
 | |
|             for item in items_from_keys_and_values(keys, values):
 | |
|                 yield item
 | |
|             return
 | |
|         entries, nentries = self._get_entries(keys)
 | |
|         for i in safe_range(nentries):
 | |
|             ep = entries[i]
 | |
|             pyop_value = PyObjectPtr.from_pyobject_ptr(ep['me_value'])
 | |
|             if not pyop_value.is_null():
 | |
|                 pyop_key = PyObjectPtr.from_pyobject_ptr(ep['me_key'])
 | |
|                 yield (pyop_key, pyop_value)
 | |
| 
 | |
|     def proxyval(self, visited):
 | |
|         # Guard against infinite loops:
 | |
|         if self.as_address() in visited:
 | |
|             return ProxyAlreadyVisited('{...}')
 | |
|         visited.add(self.as_address())
 | |
| 
 | |
|         result = {}
 | |
|         for pyop_key, pyop_value in self.iteritems():
 | |
|             proxy_key = pyop_key.proxyval(visited)
 | |
|             proxy_value = pyop_value.proxyval(visited)
 | |
|             result[proxy_key] = proxy_value
 | |
|         return result
 | |
| 
 | |
|     def write_repr(self, out, visited):
 | |
|         # Guard against infinite loops:
 | |
|         if self.as_address() in visited:
 | |
|             out.write('{...}')
 | |
|             return
 | |
|         visited.add(self.as_address())
 | |
| 
 | |
|         out.write('{')
 | |
|         first = True
 | |
|         for pyop_key, pyop_value in self.iteritems():
 | |
|             if not first:
 | |
|                 out.write(', ')
 | |
|             first = False
 | |
|             pyop_key.write_repr(out, visited)
 | |
|             out.write(': ')
 | |
|             pyop_value.write_repr(out, visited)
 | |
|         out.write('}')
 | |
| 
 | |
|     @staticmethod
 | |
|     def _get_entries(keys):
 | |
|         dk_nentries = int(keys['dk_nentries'])
 | |
|         dk_size = 1<<int(keys['dk_log2_size'])
 | |
| 
 | |
|         if dk_size <= 0xFF:
 | |
|             offset = dk_size
 | |
|         elif dk_size <= 0xFFFF:
 | |
|             offset = 2 * dk_size
 | |
|         elif dk_size <= 0xFFFFFFFF:
 | |
|             offset = 4 * dk_size
 | |
|         else:
 | |
|             offset = 8 * dk_size
 | |
| 
 | |
|         ent_addr = keys['dk_indices'].address
 | |
|         ent_addr = ent_addr.cast(_type_unsigned_char_ptr()) + offset
 | |
|         if int(keys['dk_kind']) == 0:  # DICT_KEYS_GENERAL
 | |
|             ent_ptr_t = gdb.lookup_type('PyDictKeyEntry').pointer()
 | |
|         else:
 | |
|             ent_ptr_t = gdb.lookup_type('PyDictUnicodeEntry').pointer()
 | |
|         ent_addr = ent_addr.cast(ent_ptr_t)
 | |
| 
 | |
|         return ent_addr, dk_nentries
 | |
| 
 | |
| 
 | |
| class PyListObjectPtr(PyObjectPtr):
 | |
|     _typename = 'PyListObject'
 | |
| 
 | |
|     def __getitem__(self, i):
 | |
|         # Get the gdb.Value for the (PyObject*) with the given index:
 | |
|         field_ob_item = self.field('ob_item')
 | |
|         return field_ob_item[i]
 | |
| 
 | |
|     def proxyval(self, visited):
 | |
|         # Guard against infinite loops:
 | |
|         if self.as_address() in visited:
 | |
|             return ProxyAlreadyVisited('[...]')
 | |
|         visited.add(self.as_address())
 | |
| 
 | |
|         result = [PyObjectPtr.from_pyobject_ptr(self[i]).proxyval(visited)
 | |
|                   for i in safe_range(int_from_int(self.field('ob_size')))]
 | |
|         return result
 | |
| 
 | |
|     def write_repr(self, out, visited):
 | |
|         # Guard against infinite loops:
 | |
|         if self.as_address() in visited:
 | |
|             out.write('[...]')
 | |
|             return
 | |
|         visited.add(self.as_address())
 | |
| 
 | |
|         out.write('[')
 | |
|         for i in safe_range(int_from_int(self.field('ob_size'))):
 | |
|             if i > 0:
 | |
|                 out.write(', ')
 | |
|             element = PyObjectPtr.from_pyobject_ptr(self[i])
 | |
|             element.write_repr(out, visited)
 | |
|         out.write(']')
 | |
| 
 | |
| class PyLongObjectPtr(PyObjectPtr):
 | |
|     _typename = 'PyLongObject'
 | |
| 
 | |
|     def proxyval(self, visited):
 | |
|         '''
 | |
|         Python's Include/longobjrep.h has this declaration:
 | |
|            struct _longobject {
 | |
|                PyObject_VAR_HEAD
 | |
|                digit ob_digit[1];
 | |
|            };
 | |
| 
 | |
|         with this description:
 | |
|             The absolute value of a number is equal to
 | |
|                  SUM(for i=0 through abs(ob_size)-1) ob_digit[i] * 2**(SHIFT*i)
 | |
|             Negative numbers are represented with ob_size < 0;
 | |
|             zero is represented by ob_size == 0.
 | |
| 
 | |
|         where SHIFT can be either:
 | |
|             #define PyLong_SHIFT        30
 | |
|             #define PyLong_SHIFT        15
 | |
|         '''
 | |
|         ob_size = int(self.field('ob_size'))
 | |
|         if ob_size == 0:
 | |
|             return 0
 | |
| 
 | |
|         ob_digit = self.field('ob_digit')
 | |
| 
 | |
|         if gdb.lookup_type('digit').sizeof == 2:
 | |
|             SHIFT = 15
 | |
|         else:
 | |
|             SHIFT = 30
 | |
| 
 | |
|         digits = [int(ob_digit[i]) * 2**(SHIFT*i)
 | |
|                   for i in safe_range(abs(ob_size))]
 | |
|         result = sum(digits)
 | |
|         if ob_size < 0:
 | |
|             result = -result
 | |
|         return result
 | |
| 
 | |
|     def write_repr(self, out, visited):
 | |
|         # Write this out as a Python 3 int literal, i.e. without the "L" suffix
 | |
|         proxy = self.proxyval(visited)
 | |
|         out.write("%s" % proxy)
 | |
| 
 | |
| 
 | |
| class PyBoolObjectPtr(PyLongObjectPtr):
 | |
|     """
 | |
|     Class wrapping a gdb.Value that's a PyBoolObject* i.e. one of the two
 | |
|     <bool> instances (Py_True/Py_False) within the process being debugged.
 | |
|     """
 | |
|     def proxyval(self, visited):
 | |
|         if PyLongObjectPtr.proxyval(self, visited):
 | |
|             return True
 | |
|         else:
 | |
|             return False
 | |
| 
 | |
| class PyNoneStructPtr(PyObjectPtr):
 | |
|     """
 | |
|     Class wrapping a gdb.Value that's a PyObject* pointing to the
 | |
|     singleton (we hope) _Py_NoneStruct with ob_type PyNone_Type
 | |
|     """
 | |
|     _typename = 'PyObject'
 | |
| 
 | |
|     def proxyval(self, visited):
 | |
|         return None
 | |
| 
 | |
| class PyFrameObjectPtr(PyObjectPtr):
 | |
|     _typename = 'PyFrameObject'
 | |
| 
 | |
|     def __init__(self, gdbval, cast_to=None):
 | |
|         PyObjectPtr.__init__(self, gdbval, cast_to)
 | |
| 
 | |
|         if not self.is_optimized_out():
 | |
|             self._frame = PyFramePtr(self.field('f_frame'))
 | |
| 
 | |
|     def iter_locals(self):
 | |
|         '''
 | |
|         Yield a sequence of (name,value) pairs of PyObjectPtr instances, for
 | |
|         the local variables of this frame
 | |
|         '''
 | |
|         if self.is_optimized_out():
 | |
|             return
 | |
|         return self._frame.iter_locals()
 | |
| 
 | |
|     def iter_globals(self):
 | |
|         '''
 | |
|         Yield a sequence of (name,value) pairs of PyObjectPtr instances, for
 | |
|         the global variables of this frame
 | |
|         '''
 | |
|         if self.is_optimized_out():
 | |
|             return ()
 | |
|         return self._frame.iter_globals()
 | |
| 
 | |
|     def iter_builtins(self):
 | |
|         '''
 | |
|         Yield a sequence of (name,value) pairs of PyObjectPtr instances, for
 | |
|         the builtin variables
 | |
|         '''
 | |
|         if self.is_optimized_out():
 | |
|             return ()
 | |
|         return self._frame.iter_builtins()
 | |
| 
 | |
|     def get_var_by_name(self, name):
 | |
| 
 | |
|         if self.is_optimized_out():
 | |
|             return None, None
 | |
|         return self._frame.get_var_by_name(name)
 | |
| 
 | |
|     def filename(self):
 | |
|         '''Get the path of the current Python source file, as a string'''
 | |
|         if self.is_optimized_out():
 | |
|             return FRAME_INFO_OPTIMIZED_OUT
 | |
|         return self._frame.filename()
 | |
| 
 | |
|     def current_line_num(self):
 | |
|         '''Get current line number as an integer (1-based)
 | |
| 
 | |
|         Translated from PyFrame_GetLineNumber and PyCode_Addr2Line
 | |
| 
 | |
|         See Objects/lnotab_notes.txt
 | |
|         '''
 | |
|         if self.is_optimized_out():
 | |
|             return None
 | |
|         return self._frame.current_line_num()
 | |
| 
 | |
|     def current_line(self):
 | |
|         '''Get the text of the current source line as a string, with a trailing
 | |
|         newline character'''
 | |
|         if self.is_optimized_out():
 | |
|             return FRAME_INFO_OPTIMIZED_OUT
 | |
|         return self._frame.current_line()
 | |
| 
 | |
|     def write_repr(self, out, visited):
 | |
|         if self.is_optimized_out():
 | |
|             out.write(FRAME_INFO_OPTIMIZED_OUT)
 | |
|             return
 | |
|         return self._frame.write_repr(out, visited)
 | |
| 
 | |
|     def print_traceback(self):
 | |
|         if self.is_optimized_out():
 | |
|             sys.stdout.write('  %s\n' % FRAME_INFO_OPTIMIZED_OUT)
 | |
|             return
 | |
|         return self._frame.print_traceback()
 | |
| 
 | |
| class PyFramePtr:
 | |
| 
 | |
|     def __init__(self, gdbval):
 | |
|         self._gdbval = gdbval
 | |
| 
 | |
|         if not self.is_optimized_out():
 | |
|             self.co = self._f_code()
 | |
|             self.co_name = self.co.pyop_field('co_name')
 | |
|             self.co_filename = self.co.pyop_field('co_filename')
 | |
| 
 | |
|             self.f_lasti = self._f_lasti()
 | |
|             self.co_nlocals = int_from_int(self.co.field('co_nlocals'))
 | |
|             pnames = self.co.field('co_localsplusnames')
 | |
|             self.co_localsplusnames = PyTupleObjectPtr.from_pyobject_ptr(pnames)
 | |
| 
 | |
|     def is_optimized_out(self):
 | |
|         return self._gdbval.is_optimized_out
 | |
| 
 | |
|     def iter_locals(self):
 | |
|         '''
 | |
|         Yield a sequence of (name,value) pairs of PyObjectPtr instances, for
 | |
|         the local variables of this frame
 | |
|         '''
 | |
|         if self.is_optimized_out():
 | |
|             return
 | |
| 
 | |
| 
 | |
|         obj_ptr_ptr = gdb.lookup_type("PyObject").pointer().pointer()
 | |
| 
 | |
|         localsplus = self._gdbval["localsplus"].cast(obj_ptr_ptr)
 | |
| 
 | |
|         for i in safe_range(self.co_nlocals):
 | |
|             pyop_value = PyObjectPtr.from_pyobject_ptr(localsplus[i])
 | |
|             if pyop_value.is_null():
 | |
|                 continue
 | |
|             pyop_name = PyObjectPtr.from_pyobject_ptr(self.co_localsplusnames[i])
 | |
|             yield (pyop_name, pyop_value)
 | |
| 
 | |
|     def _f_special(self, name, convert=PyObjectPtr.from_pyobject_ptr):
 | |
|         return convert(self._gdbval[name])
 | |
| 
 | |
|     def _f_globals(self):
 | |
|         return self._f_special("f_globals")
 | |
| 
 | |
|     def _f_builtins(self):
 | |
|         return self._f_special("f_builtins")
 | |
| 
 | |
|     def _f_code(self):
 | |
|         return self._f_special("f_code", PyCodeObjectPtr.from_pyobject_ptr)
 | |
| 
 | |
|     def _f_nlocalsplus(self):
 | |
|         return self._f_special("nlocalsplus", int_from_int)
 | |
| 
 | |
|     def _f_lasti(self):
 | |
|         codeunit_p = gdb.lookup_type("_Py_CODEUNIT").pointer()
 | |
|         prev_instr = self._gdbval["prev_instr"]
 | |
|         first_instr = self._f_code().field("co_code_adaptive").cast(codeunit_p)
 | |
|         return int(prev_instr - first_instr)
 | |
| 
 | |
|     def is_shim(self):
 | |
|         return self._f_special("owner", int) == FRAME_OWNED_BY_CSTACK
 | |
| 
 | |
|     def previous(self):
 | |
|         return self._f_special("previous", PyFramePtr)
 | |
| 
 | |
|     def iter_globals(self):
 | |
|         '''
 | |
|         Yield a sequence of (name,value) pairs of PyObjectPtr instances, for
 | |
|         the global variables of this frame
 | |
|         '''
 | |
|         if self.is_optimized_out():
 | |
|             return ()
 | |
| 
 | |
|         pyop_globals = self._f_globals()
 | |
|         return pyop_globals.iteritems()
 | |
| 
 | |
|     def iter_builtins(self):
 | |
|         '''
 | |
|         Yield a sequence of (name,value) pairs of PyObjectPtr instances, for
 | |
|         the builtin variables
 | |
|         '''
 | |
|         if self.is_optimized_out():
 | |
|             return ()
 | |
| 
 | |
|         pyop_builtins = self._f_builtins()
 | |
|         return pyop_builtins.iteritems()
 | |
| 
 | |
|     def get_var_by_name(self, name):
 | |
|         '''
 | |
|         Look for the named local variable, returning a (PyObjectPtr, scope) pair
 | |
|         where scope is a string 'local', 'global', 'builtin'
 | |
| 
 | |
|         If not found, return (None, None)
 | |
|         '''
 | |
|         for pyop_name, pyop_value in self.iter_locals():
 | |
|             if name == pyop_name.proxyval(set()):
 | |
|                 return pyop_value, 'local'
 | |
|         for pyop_name, pyop_value in self.iter_globals():
 | |
|             if name == pyop_name.proxyval(set()):
 | |
|                 return pyop_value, 'global'
 | |
|         for pyop_name, pyop_value in self.iter_builtins():
 | |
|             if name == pyop_name.proxyval(set()):
 | |
|                 return pyop_value, 'builtin'
 | |
|         return None, None
 | |
| 
 | |
|     def filename(self):
 | |
|         '''Get the path of the current Python source file, as a string'''
 | |
|         if self.is_optimized_out():
 | |
|             return FRAME_INFO_OPTIMIZED_OUT
 | |
|         return self.co_filename.proxyval(set())
 | |
| 
 | |
|     def current_line_num(self):
 | |
|         '''Get current line number as an integer (1-based)
 | |
| 
 | |
|         Translated from PyFrame_GetLineNumber and PyCode_Addr2Line
 | |
| 
 | |
|         See Objects/lnotab_notes.txt
 | |
|         '''
 | |
|         if self.is_optimized_out():
 | |
|             return None
 | |
|         try:
 | |
|             return self.co.addr2line(self.f_lasti)
 | |
|         except Exception as ex:
 | |
|             # bpo-34989: addr2line() is a complex function, it can fail in many
 | |
|             # ways. For example, it fails with a TypeError on "FakeRepr" if
 | |
|             # gdb fails to load debug symbols. Use a catch-all "except
 | |
|             # Exception" to make the whole function safe. The caller has to
 | |
|             # handle None anyway for optimized Python.
 | |
|             return None
 | |
| 
 | |
|     def current_line(self):
 | |
|         '''Get the text of the current source line as a string, with a trailing
 | |
|         newline character'''
 | |
|         if self.is_optimized_out():
 | |
|             return FRAME_INFO_OPTIMIZED_OUT
 | |
| 
 | |
|         lineno = self.current_line_num()
 | |
|         if lineno is None:
 | |
|             return '(failed to get frame line number)'
 | |
| 
 | |
|         filename = self.filename()
 | |
|         try:
 | |
|             with open(os_fsencode(filename), 'r', encoding="utf-8") as fp:
 | |
|                 lines = fp.readlines()
 | |
|         except IOError:
 | |
|             return None
 | |
| 
 | |
|         try:
 | |
|             # Convert from 1-based current_line_num to 0-based list offset
 | |
|             return lines[lineno - 1]
 | |
|         except IndexError:
 | |
|             return None
 | |
| 
 | |
|     def write_repr(self, out, visited):
 | |
|         if self.is_optimized_out():
 | |
|             out.write(FRAME_INFO_OPTIMIZED_OUT)
 | |
|             return
 | |
|         lineno = self.current_line_num()
 | |
|         lineno = str(lineno) if lineno is not None else "?"
 | |
|         out.write('Frame 0x%x, for file %s, line %s, in %s ('
 | |
|                   % (self.as_address(),
 | |
|                      self.co_filename.proxyval(visited),
 | |
|                      lineno,
 | |
|                      self.co_name.proxyval(visited)))
 | |
|         first = True
 | |
|         for pyop_name, pyop_value in self.iter_locals():
 | |
|             if not first:
 | |
|                 out.write(', ')
 | |
|             first = False
 | |
| 
 | |
|             out.write(pyop_name.proxyval(visited))
 | |
|             out.write('=')
 | |
|             pyop_value.write_repr(out, visited)
 | |
| 
 | |
|         out.write(')')
 | |
| 
 | |
|     def as_address(self):
 | |
|         return int(self._gdbval)
 | |
| 
 | |
|     def print_traceback(self):
 | |
|         if self.is_optimized_out():
 | |
|             sys.stdout.write('  %s\n' % FRAME_INFO_OPTIMIZED_OUT)
 | |
|             return
 | |
|         visited = set()
 | |
|         lineno = self.current_line_num()
 | |
|         lineno = str(lineno) if lineno is not None else "?"
 | |
|         sys.stdout.write('  File "%s", line %s, in %s\n'
 | |
|                   % (self.co_filename.proxyval(visited),
 | |
|                      lineno,
 | |
|                      self.co_name.proxyval(visited)))
 | |
| 
 | |
|     def get_truncated_repr(self, maxlen):
 | |
|         '''
 | |
|         Get a repr-like string for the data, but truncate it at "maxlen" bytes
 | |
|         (ending the object graph traversal as soon as you do)
 | |
|         '''
 | |
|         out = TruncatedStringIO(maxlen)
 | |
|         try:
 | |
|             self.write_repr(out, set())
 | |
|         except StringTruncated:
 | |
|             # Truncation occurred:
 | |
|             return out.getvalue() + '...(truncated)'
 | |
| 
 | |
|         # No truncation occurred:
 | |
|         return out.getvalue()
 | |
| 
 | |
| class PySetObjectPtr(PyObjectPtr):
 | |
|     _typename = 'PySetObject'
 | |
| 
 | |
|     @classmethod
 | |
|     def _dummy_key(self):
 | |
|         return gdb.lookup_global_symbol('_PySet_Dummy').value()
 | |
| 
 | |
|     def __iter__(self):
 | |
|         dummy_ptr = self._dummy_key()
 | |
|         table = self.field('table')
 | |
|         for i in safe_range(self.field('mask') + 1):
 | |
|             setentry = table[i]
 | |
|             key = setentry['key']
 | |
|             if key != 0 and key != dummy_ptr:
 | |
|                 yield PyObjectPtr.from_pyobject_ptr(key)
 | |
| 
 | |
|     def proxyval(self, visited):
 | |
|         # Guard against infinite loops:
 | |
|         if self.as_address() in visited:
 | |
|             return ProxyAlreadyVisited('%s(...)' % self.safe_tp_name())
 | |
|         visited.add(self.as_address())
 | |
| 
 | |
|         members = (key.proxyval(visited) for key in self)
 | |
|         if self.safe_tp_name() == 'frozenset':
 | |
|             return frozenset(members)
 | |
|         else:
 | |
|             return set(members)
 | |
| 
 | |
|     def write_repr(self, out, visited):
 | |
|         # Emulate Python 3's set_repr
 | |
|         tp_name = self.safe_tp_name()
 | |
| 
 | |
|         # Guard against infinite loops:
 | |
|         if self.as_address() in visited:
 | |
|             out.write('(...)')
 | |
|             return
 | |
|         visited.add(self.as_address())
 | |
| 
 | |
|         # Python 3's set_repr special-cases the empty set:
 | |
|         if not self.field('used'):
 | |
|             out.write(tp_name)
 | |
|             out.write('()')
 | |
|             return
 | |
| 
 | |
|         # Python 3 uses {} for set literals:
 | |
|         if tp_name != 'set':
 | |
|             out.write(tp_name)
 | |
|             out.write('(')
 | |
| 
 | |
|         out.write('{')
 | |
|         first = True
 | |
|         for key in self:
 | |
|             if not first:
 | |
|                 out.write(', ')
 | |
|             first = False
 | |
|             key.write_repr(out, visited)
 | |
|         out.write('}')
 | |
| 
 | |
|         if tp_name != 'set':
 | |
|             out.write(')')
 | |
| 
 | |
| 
 | |
| class PyBytesObjectPtr(PyObjectPtr):
 | |
|     _typename = 'PyBytesObject'
 | |
| 
 | |
|     def __str__(self):
 | |
|         field_ob_size = self.field('ob_size')
 | |
|         field_ob_sval = self.field('ob_sval')
 | |
|         char_ptr = field_ob_sval.address.cast(_type_unsigned_char_ptr())
 | |
|         return ''.join([chr(char_ptr[i]) for i in safe_range(field_ob_size)])
 | |
| 
 | |
|     def proxyval(self, visited):
 | |
|         return str(self)
 | |
| 
 | |
|     def write_repr(self, out, visited):
 | |
|         # Write this out as a Python 3 bytes literal, i.e. with a "b" prefix
 | |
| 
 | |
|         # Get a PyStringObject* within the Python 2 gdb process:
 | |
|         proxy = self.proxyval(visited)
 | |
| 
 | |
|         # Transliteration of Python 3's Objects/bytesobject.c:PyBytes_Repr
 | |
|         # to Python 2 code:
 | |
|         quote = "'"
 | |
|         if "'" in proxy and not '"' in proxy:
 | |
|             quote = '"'
 | |
|         out.write('b')
 | |
|         out.write(quote)
 | |
|         for byte in proxy:
 | |
|             if byte == quote or byte == '\\':
 | |
|                 out.write('\\')
 | |
|                 out.write(byte)
 | |
|             elif byte == '\t':
 | |
|                 out.write('\\t')
 | |
|             elif byte == '\n':
 | |
|                 out.write('\\n')
 | |
|             elif byte == '\r':
 | |
|                 out.write('\\r')
 | |
|             elif byte < ' ' or ord(byte) >= 0x7f:
 | |
|                 out.write('\\x')
 | |
|                 out.write(hexdigits[(ord(byte) & 0xf0) >> 4])
 | |
|                 out.write(hexdigits[ord(byte) & 0xf])
 | |
|             else:
 | |
|                 out.write(byte)
 | |
|         out.write(quote)
 | |
| 
 | |
| class PyTupleObjectPtr(PyObjectPtr):
 | |
|     _typename = 'PyTupleObject'
 | |
| 
 | |
|     def __getitem__(self, i):
 | |
|         # Get the gdb.Value for the (PyObject*) with the given index:
 | |
|         field_ob_item = self.field('ob_item')
 | |
|         return field_ob_item[i]
 | |
| 
 | |
|     def proxyval(self, visited):
 | |
|         # Guard against infinite loops:
 | |
|         if self.as_address() in visited:
 | |
|             return ProxyAlreadyVisited('(...)')
 | |
|         visited.add(self.as_address())
 | |
| 
 | |
|         result = tuple(PyObjectPtr.from_pyobject_ptr(self[i]).proxyval(visited)
 | |
|                        for i in safe_range(int_from_int(self.field('ob_size'))))
 | |
|         return result
 | |
| 
 | |
|     def write_repr(self, out, visited):
 | |
|         # Guard against infinite loops:
 | |
|         if self.as_address() in visited:
 | |
|             out.write('(...)')
 | |
|             return
 | |
|         visited.add(self.as_address())
 | |
| 
 | |
|         out.write('(')
 | |
|         for i in safe_range(int_from_int(self.field('ob_size'))):
 | |
|             if i > 0:
 | |
|                 out.write(', ')
 | |
|             element = PyObjectPtr.from_pyobject_ptr(self[i])
 | |
|             element.write_repr(out, visited)
 | |
|         if self.field('ob_size') == 1:
 | |
|             out.write(',)')
 | |
|         else:
 | |
|             out.write(')')
 | |
| 
 | |
| class PyTypeObjectPtr(PyObjectPtr):
 | |
|     _typename = 'PyTypeObject'
 | |
| 
 | |
| 
 | |
| def _unichr_is_printable(char):
 | |
|     # Logic adapted from Python 3's Tools/unicode/makeunicodedata.py
 | |
|     if char == u" ":
 | |
|         return True
 | |
|     import unicodedata
 | |
|     return unicodedata.category(char) not in ("C", "Z")
 | |
| 
 | |
| 
 | |
| class PyUnicodeObjectPtr(PyObjectPtr):
 | |
|     _typename = 'PyUnicodeObject'
 | |
| 
 | |
|     def char_width(self):
 | |
|         _type_Py_UNICODE = gdb.lookup_type('Py_UNICODE')
 | |
|         return _type_Py_UNICODE.sizeof
 | |
| 
 | |
|     def proxyval(self, visited):
 | |
|         compact = self.field('_base')
 | |
|         ascii = compact['_base']
 | |
|         state = ascii['state']
 | |
|         is_compact_ascii = (int(state['ascii']) and int(state['compact']))
 | |
|         field_length = int(ascii['length'])
 | |
|         if is_compact_ascii:
 | |
|             field_str = ascii.address + 1
 | |
|         elif int(state['compact']):
 | |
|             field_str = compact.address + 1
 | |
|         else:
 | |
|             field_str = self.field('data')['any']
 | |
|         repr_kind = int(state['kind'])
 | |
|         if repr_kind == 1:
 | |
|             field_str = field_str.cast(_type_unsigned_char_ptr())
 | |
|         elif repr_kind == 2:
 | |
|             field_str = field_str.cast(_type_unsigned_short_ptr())
 | |
|         elif repr_kind == 4:
 | |
|             field_str = field_str.cast(_type_unsigned_int_ptr())
 | |
| 
 | |
|         # Gather a list of ints from the Py_UNICODE array; these are either
 | |
|         # UCS-1, UCS-2 or UCS-4 code points:
 | |
|         Py_UNICODEs = [int(field_str[i]) for i in safe_range(field_length)]
 | |
| 
 | |
|         # Convert the int code points to unicode characters, and generate a
 | |
|         # local unicode instance.
 | |
|         result = u''.join(map(chr, Py_UNICODEs))
 | |
|         return result
 | |
| 
 | |
|     def write_repr(self, out, visited):
 | |
|         # Write this out as a Python 3 str literal, i.e. without a "u" prefix
 | |
| 
 | |
|         # Get a PyUnicodeObject* within the Python 2 gdb process:
 | |
|         proxy = self.proxyval(visited)
 | |
| 
 | |
|         # Transliteration of Python 3's Object/unicodeobject.c:unicode_repr
 | |
|         # to Python 2:
 | |
|         if "'" in proxy and '"' not in proxy:
 | |
|             quote = '"'
 | |
|         else:
 | |
|             quote = "'"
 | |
|         out.write(quote)
 | |
| 
 | |
|         i = 0
 | |
|         while i < len(proxy):
 | |
|             ch = proxy[i]
 | |
|             i += 1
 | |
| 
 | |
|             # Escape quotes and backslashes
 | |
|             if ch == quote or ch == '\\':
 | |
|                 out.write('\\')
 | |
|                 out.write(ch)
 | |
| 
 | |
|             #  Map special whitespace to '\t', \n', '\r'
 | |
|             elif ch == '\t':
 | |
|                 out.write('\\t')
 | |
|             elif ch == '\n':
 | |
|                 out.write('\\n')
 | |
|             elif ch == '\r':
 | |
|                 out.write('\\r')
 | |
| 
 | |
|             # Map non-printable US ASCII to '\xhh' */
 | |
|             elif ch < ' ' or ord(ch) == 0x7F:
 | |
|                 out.write('\\x')
 | |
|                 out.write(hexdigits[(ord(ch) >> 4) & 0x000F])
 | |
|                 out.write(hexdigits[ord(ch) & 0x000F])
 | |
| 
 | |
|             # Copy ASCII characters as-is
 | |
|             elif ord(ch) < 0x7F:
 | |
|                 out.write(ch)
 | |
| 
 | |
|             # Non-ASCII characters
 | |
|             else:
 | |
|                 ucs = ch
 | |
|                 ch2 = None
 | |
| 
 | |
|                 printable = ucs.isprintable()
 | |
|                 if printable:
 | |
|                     try:
 | |
|                         ucs.encode(ENCODING)
 | |
|                     except UnicodeEncodeError:
 | |
|                         printable = False
 | |
| 
 | |
|                 # Map Unicode whitespace and control characters
 | |
|                 # (categories Z* and C* except ASCII space)
 | |
|                 if not printable:
 | |
|                     if ch2 is not None:
 | |
|                         # Match Python 3's representation of non-printable
 | |
|                         # wide characters.
 | |
|                         code = (ord(ch) & 0x03FF) << 10
 | |
|                         code |= ord(ch2) & 0x03FF
 | |
|                         code += 0x00010000
 | |
|                     else:
 | |
|                         code = ord(ucs)
 | |
| 
 | |
|                     # Map 8-bit characters to '\\xhh'
 | |
|                     if code <= 0xff:
 | |
|                         out.write('\\x')
 | |
|                         out.write(hexdigits[(code >> 4) & 0x000F])
 | |
|                         out.write(hexdigits[code & 0x000F])
 | |
|                     # Map 21-bit characters to '\U00xxxxxx'
 | |
|                     elif code >= 0x10000:
 | |
|                         out.write('\\U')
 | |
|                         out.write(hexdigits[(code >> 28) & 0x0000000F])
 | |
|                         out.write(hexdigits[(code >> 24) & 0x0000000F])
 | |
|                         out.write(hexdigits[(code >> 20) & 0x0000000F])
 | |
|                         out.write(hexdigits[(code >> 16) & 0x0000000F])
 | |
|                         out.write(hexdigits[(code >> 12) & 0x0000000F])
 | |
|                         out.write(hexdigits[(code >> 8) & 0x0000000F])
 | |
|                         out.write(hexdigits[(code >> 4) & 0x0000000F])
 | |
|                         out.write(hexdigits[code & 0x0000000F])
 | |
|                     # Map 16-bit characters to '\uxxxx'
 | |
|                     else:
 | |
|                         out.write('\\u')
 | |
|                         out.write(hexdigits[(code >> 12) & 0x000F])
 | |
|                         out.write(hexdigits[(code >> 8) & 0x000F])
 | |
|                         out.write(hexdigits[(code >> 4) & 0x000F])
 | |
|                         out.write(hexdigits[code & 0x000F])
 | |
|                 else:
 | |
|                     # Copy characters as-is
 | |
|                     out.write(ch)
 | |
|                     if ch2 is not None:
 | |
|                         out.write(ch2)
 | |
| 
 | |
|         out.write(quote)
 | |
| 
 | |
| 
 | |
| class wrapperobject(PyObjectPtr):
 | |
|     _typename = 'wrapperobject'
 | |
| 
 | |
|     def safe_name(self):
 | |
|         try:
 | |
|             name = self.field('descr')['d_base']['name'].string()
 | |
|             return repr(name)
 | |
|         except (NullPyObjectPtr, RuntimeError, UnicodeDecodeError):
 | |
|             return '<unknown name>'
 | |
| 
 | |
|     def safe_tp_name(self):
 | |
|         try:
 | |
|             return self.field('self')['ob_type']['tp_name'].string()
 | |
|         except (NullPyObjectPtr, RuntimeError, UnicodeDecodeError):
 | |
|             return '<unknown tp_name>'
 | |
| 
 | |
|     def safe_self_addresss(self):
 | |
|         try:
 | |
|             address = int(self.field('self'))
 | |
|             return '%#x' % address
 | |
|         except (NullPyObjectPtr, RuntimeError):
 | |
|             return '<failed to get self address>'
 | |
| 
 | |
|     def proxyval(self, visited):
 | |
|         name = self.safe_name()
 | |
|         tp_name = self.safe_tp_name()
 | |
|         self_address = self.safe_self_addresss()
 | |
|         return ("<method-wrapper %s of %s object at %s>"
 | |
|                 % (name, tp_name, self_address))
 | |
| 
 | |
|     def write_repr(self, out, visited):
 | |
|         proxy = self.proxyval(visited)
 | |
|         out.write(proxy)
 | |
| 
 | |
| 
 | |
| def int_from_int(gdbval):
 | |
|     return int(gdbval)
 | |
| 
 | |
| 
 | |
| def stringify(val):
 | |
|     # TODO: repr() puts everything on one line; pformat can be nicer, but
 | |
|     # can lead to v.long results; this function isolates the choice
 | |
|     if True:
 | |
|         return repr(val)
 | |
|     else:
 | |
|         from pprint import pformat
 | |
|         return pformat(val)
 | |
| 
 | |
| 
 | |
| class PyObjectPtrPrinter:
 | |
|     "Prints a (PyObject*)"
 | |
| 
 | |
|     def __init__ (self, gdbval):
 | |
|         self.gdbval = gdbval
 | |
| 
 | |
|     def to_string (self):
 | |
|         pyop = PyObjectPtr.from_pyobject_ptr(self.gdbval)
 | |
|         if True:
 | |
|             return pyop.get_truncated_repr(MAX_OUTPUT_LEN)
 | |
|         else:
 | |
|             # Generate full proxy value then stringify it.
 | |
|             # Doing so could be expensive
 | |
|             proxyval = pyop.proxyval(set())
 | |
|             return stringify(proxyval)
 | |
| 
 | |
| def pretty_printer_lookup(gdbval):
 | |
|     type = gdbval.type.unqualified()
 | |
|     if type.code != gdb.TYPE_CODE_PTR:
 | |
|         return None
 | |
| 
 | |
|     type = type.target().unqualified()
 | |
|     t = str(type)
 | |
|     if t in ("PyObject", "PyFrameObject", "PyUnicodeObject", "wrapperobject"):
 | |
|         return PyObjectPtrPrinter(gdbval)
 | |
| 
 | |
| """
 | |
| During development, I've been manually invoking the code in this way:
 | |
| (gdb) python
 | |
| 
 | |
| import sys
 | |
| sys.path.append('/home/david/coding/python-gdb')
 | |
| import libpython
 | |
| end
 | |
| 
 | |
| then reloading it after each edit like this:
 | |
| (gdb) python reload(libpython)
 | |
| 
 | |
| The following code should ensure that the prettyprinter is registered
 | |
| if the code is autoloaded by gdb when visiting libpython.so, provided
 | |
| that this python file is installed to the same path as the library (or its
 | |
| .debug file) plus a "-gdb.py" suffix, e.g:
 | |
|   /usr/lib/libpython2.6.so.1.0-gdb.py
 | |
|   /usr/lib/debug/usr/lib/libpython2.6.so.1.0.debug-gdb.py
 | |
| """
 | |
| def register (obj):
 | |
|     if obj is None:
 | |
|         obj = gdb
 | |
| 
 | |
|     # Wire up the pretty-printer
 | |
|     obj.pretty_printers.append(pretty_printer_lookup)
 | |
| 
 | |
| register (gdb.current_objfile ())
 | |
| 
 | |
| 
 | |
| 
 | |
| # Unfortunately, the exact API exposed by the gdb module varies somewhat
 | |
| # from build to build
 | |
| # See http://bugs.python.org/issue8279?#msg102276
 | |
| 
 | |
| class Frame(object):
 | |
|     '''
 | |
|     Wrapper for gdb.Frame, adding various methods
 | |
|     '''
 | |
|     def __init__(self, gdbframe):
 | |
|         self._gdbframe = gdbframe
 | |
| 
 | |
|     def older(self):
 | |
|         older = self._gdbframe.older()
 | |
|         if older:
 | |
|             return Frame(older)
 | |
|         else:
 | |
|             return None
 | |
| 
 | |
|     def newer(self):
 | |
|         newer = self._gdbframe.newer()
 | |
|         if newer:
 | |
|             return Frame(newer)
 | |
|         else:
 | |
|             return None
 | |
| 
 | |
|     def select(self):
 | |
|         '''If supported, select this frame and return True; return False if unsupported
 | |
| 
 | |
|         Not all builds have a gdb.Frame.select method; seems to be present on Fedora 12
 | |
|         onwards, but absent on Ubuntu buildbot'''
 | |
|         if not hasattr(self._gdbframe, 'select'):
 | |
|             print ('Unable to select frame: '
 | |
|                    'this build of gdb does not expose a gdb.Frame.select method')
 | |
|             return False
 | |
|         self._gdbframe.select()
 | |
|         return True
 | |
| 
 | |
|     def get_index(self):
 | |
|         '''Calculate index of frame, starting at 0 for the newest frame within
 | |
|         this thread'''
 | |
|         index = 0
 | |
|         # Go down until you reach the newest frame:
 | |
|         iter_frame = self
 | |
|         while iter_frame.newer():
 | |
|             index += 1
 | |
|             iter_frame = iter_frame.newer()
 | |
|         return index
 | |
| 
 | |
|     # We divide frames into:
 | |
|     #   - "python frames":
 | |
|     #       - "bytecode frames" i.e. PyEval_EvalFrameEx
 | |
|     #       - "other python frames": things that are of interest from a python
 | |
|     #         POV, but aren't bytecode (e.g. GC, GIL)
 | |
|     #   - everything else
 | |
| 
 | |
|     def is_python_frame(self):
 | |
|         '''Is this a _PyEval_EvalFrameDefault frame, or some other important
 | |
|         frame? (see is_other_python_frame for what "important" means in this
 | |
|         context)'''
 | |
|         if self.is_evalframe():
 | |
|             return True
 | |
|         if self.is_other_python_frame():
 | |
|             return True
 | |
|         return False
 | |
| 
 | |
|     def is_evalframe(self):
 | |
|         '''Is this a _PyEval_EvalFrameDefault frame?'''
 | |
|         if self._gdbframe.name() == EVALFRAME:
 | |
|             '''
 | |
|             I believe we also need to filter on the inline
 | |
|             struct frame_id.inline_depth, only regarding frames with
 | |
|             an inline depth of 0 as actually being this function
 | |
| 
 | |
|             So we reject those with type gdb.INLINE_FRAME
 | |
|             '''
 | |
|             if self._gdbframe.type() == gdb.NORMAL_FRAME:
 | |
|                 # We have a _PyEval_EvalFrameDefault frame:
 | |
|                 return True
 | |
| 
 | |
|         return False
 | |
| 
 | |
|     def is_other_python_frame(self):
 | |
|         '''Is this frame worth displaying in python backtraces?
 | |
|         Examples:
 | |
|           - waiting on the GIL
 | |
|           - garbage-collecting
 | |
|           - within a CFunction
 | |
|          If it is, return a descriptive string
 | |
|          For other frames, return False
 | |
|          '''
 | |
|         if self.is_waiting_for_gil():
 | |
|             return 'Waiting for the GIL'
 | |
| 
 | |
|         if self.is_gc_collect():
 | |
|             return 'Garbage-collecting'
 | |
| 
 | |
|         # Detect invocations of PyCFunction instances:
 | |
|         frame = self._gdbframe
 | |
|         caller = frame.name()
 | |
|         if not caller:
 | |
|             return False
 | |
| 
 | |
|         if (caller.startswith('cfunction_vectorcall_') or
 | |
|             caller == 'cfunction_call'):
 | |
|             arg_name = 'func'
 | |
|             # Within that frame:
 | |
|             #   "func" is the local containing the PyObject* of the
 | |
|             # PyCFunctionObject instance
 | |
|             #   "f" is the same value, but cast to (PyCFunctionObject*)
 | |
|             #   "self" is the (PyObject*) of the 'self'
 | |
|             try:
 | |
|                 # Use the prettyprinter for the func:
 | |
|                 func = frame.read_var(arg_name)
 | |
|                 return str(func)
 | |
|             except ValueError:
 | |
|                 return ('PyCFunction invocation (unable to read %s: '
 | |
|                         'missing debuginfos?)' % arg_name)
 | |
|             except RuntimeError:
 | |
|                 return 'PyCFunction invocation (unable to read %s)' % arg_name
 | |
| 
 | |
|         if caller == 'wrapper_call':
 | |
|             arg_name = 'wp'
 | |
|             try:
 | |
|                 func = frame.read_var(arg_name)
 | |
|                 return str(func)
 | |
|             except ValueError:
 | |
|                 return ('<wrapper_call invocation (unable to read %s: '
 | |
|                         'missing debuginfos?)>' % arg_name)
 | |
|             except RuntimeError:
 | |
|                 return '<wrapper_call invocation (unable to read %s)>' % arg_name
 | |
| 
 | |
|         # This frame isn't worth reporting:
 | |
|         return False
 | |
| 
 | |
|     def is_waiting_for_gil(self):
 | |
|         '''Is this frame waiting on the GIL?'''
 | |
|         # This assumes the _POSIX_THREADS version of Python/ceval_gil.c:
 | |
|         name = self._gdbframe.name()
 | |
|         if name:
 | |
|             return (name == 'take_gil')
 | |
| 
 | |
|     def is_gc_collect(self):
 | |
|         '''Is this frame gc_collect_main() within the garbage-collector?'''
 | |
|         return self._gdbframe.name() in ('collect', 'gc_collect_main')
 | |
| 
 | |
|     def get_pyop(self):
 | |
|         try:
 | |
|             frame = self._gdbframe.read_var('frame')
 | |
|             frame = PyFramePtr(frame)
 | |
|             if not frame.is_optimized_out():
 | |
|                 return frame
 | |
|             cframe = self._gdbframe.read_var('cframe')
 | |
|             if cframe is None:
 | |
|                 return None
 | |
|             frame = PyFramePtr(cframe["current_frame"])
 | |
|             if frame and not frame.is_optimized_out():
 | |
|                 return frame
 | |
|             return None
 | |
|         except ValueError:
 | |
|             return None
 | |
| 
 | |
|     @classmethod
 | |
|     def get_selected_frame(cls):
 | |
|         _gdbframe = gdb.selected_frame()
 | |
|         if _gdbframe:
 | |
|             return Frame(_gdbframe)
 | |
|         return None
 | |
| 
 | |
|     @classmethod
 | |
|     def get_selected_python_frame(cls):
 | |
|         '''Try to obtain the Frame for the python-related code in the selected
 | |
|         frame, or None'''
 | |
|         try:
 | |
|             frame = cls.get_selected_frame()
 | |
|         except gdb.error:
 | |
|             # No frame: Python didn't start yet
 | |
|             return None
 | |
| 
 | |
|         while frame:
 | |
|             if frame.is_python_frame():
 | |
|                 return frame
 | |
|             frame = frame.older()
 | |
| 
 | |
|         # Not found:
 | |
|         return None
 | |
| 
 | |
|     @classmethod
 | |
|     def get_selected_bytecode_frame(cls):
 | |
|         '''Try to obtain the Frame for the python bytecode interpreter in the
 | |
|         selected GDB frame, or None'''
 | |
|         frame = cls.get_selected_frame()
 | |
| 
 | |
|         while frame:
 | |
|             if frame.is_evalframe():
 | |
|                 return frame
 | |
|             frame = frame.older()
 | |
| 
 | |
|         # Not found:
 | |
|         return None
 | |
| 
 | |
|     def print_summary(self):
 | |
|         if self.is_evalframe():
 | |
|             interp_frame = self.get_pyop()
 | |
|             while True:
 | |
|                 if interp_frame:
 | |
|                     if interp_frame.is_shim():
 | |
|                         break
 | |
|                     line = interp_frame.get_truncated_repr(MAX_OUTPUT_LEN)
 | |
|                     sys.stdout.write('#%i %s\n' % (self.get_index(), line))
 | |
|                     if not interp_frame.is_optimized_out():
 | |
|                         line = interp_frame.current_line()
 | |
|                         if line is not None:
 | |
|                             sys.stdout.write('    %s\n' % line.strip())
 | |
|                 else:
 | |
|                     sys.stdout.write('#%i (unable to read python frame information)\n' % self.get_index())
 | |
|                     break
 | |
|                 interp_frame = interp_frame.previous()
 | |
|         else:
 | |
|             info = self.is_other_python_frame()
 | |
|             if info:
 | |
|                 sys.stdout.write('#%i %s\n' % (self.get_index(), info))
 | |
|             else:
 | |
|                 sys.stdout.write('#%i\n' % self.get_index())
 | |
| 
 | |
|     def print_traceback(self):
 | |
|         if self.is_evalframe():
 | |
|             interp_frame = self.get_pyop()
 | |
|             while True:
 | |
|                 if interp_frame:
 | |
|                     if interp_frame.is_shim():
 | |
|                         break
 | |
|                     interp_frame.print_traceback()
 | |
|                     if not interp_frame.is_optimized_out():
 | |
|                         line = interp_frame.current_line()
 | |
|                         if line is not None:
 | |
|                             sys.stdout.write('    %s\n' % line.strip())
 | |
|                 else:
 | |
|                     sys.stdout.write('  (unable to read python frame information)\n')
 | |
|                     break
 | |
|                 interp_frame = interp_frame.previous()
 | |
|         else:
 | |
|             info = self.is_other_python_frame()
 | |
|             if info:
 | |
|                 sys.stdout.write('  %s\n' % info)
 | |
|             else:
 | |
|                 sys.stdout.write('  (not a python frame)\n')
 | |
| 
 | |
| class PyList(gdb.Command):
 | |
|     '''List the current Python source code, if any
 | |
| 
 | |
|     Use
 | |
|        py-list START
 | |
|     to list at a different line number within the python source.
 | |
| 
 | |
|     Use
 | |
|        py-list START, END
 | |
|     to list a specific range of lines within the python source.
 | |
|     '''
 | |
| 
 | |
|     def __init__(self):
 | |
|         gdb.Command.__init__ (self,
 | |
|                               "py-list",
 | |
|                               gdb.COMMAND_FILES,
 | |
|                               gdb.COMPLETE_NONE)
 | |
| 
 | |
| 
 | |
|     def invoke(self, args, from_tty):
 | |
|         import re
 | |
| 
 | |
|         start = None
 | |
|         end = None
 | |
| 
 | |
|         m = re.match(r'\s*(\d+)\s*', args)
 | |
|         if m:
 | |
|             start = int(m.group(0))
 | |
|             end = start + 10
 | |
| 
 | |
|         m = re.match(r'\s*(\d+)\s*,\s*(\d+)\s*', args)
 | |
|         if m:
 | |
|             start, end = map(int, m.groups())
 | |
| 
 | |
|         # py-list requires an actual PyEval_EvalFrameEx frame:
 | |
|         frame = Frame.get_selected_bytecode_frame()
 | |
|         if not frame:
 | |
|             print('Unable to locate gdb frame for python bytecode interpreter')
 | |
|             return
 | |
| 
 | |
|         pyop = frame.get_pyop()
 | |
|         if not pyop or pyop.is_optimized_out():
 | |
|             print(UNABLE_READ_INFO_PYTHON_FRAME)
 | |
|             return
 | |
| 
 | |
|         filename = pyop.filename()
 | |
|         lineno = pyop.current_line_num()
 | |
|         if lineno is None:
 | |
|             print('Unable to read python frame line number')
 | |
|             return
 | |
| 
 | |
|         if start is None:
 | |
|             start = lineno - 5
 | |
|             end = lineno + 5
 | |
| 
 | |
|         if start<1:
 | |
|             start = 1
 | |
| 
 | |
|         try:
 | |
|             f = open(os_fsencode(filename), 'r', encoding="utf-8")
 | |
|         except IOError as err:
 | |
|             sys.stdout.write('Unable to open %s: %s\n'
 | |
|                              % (filename, err))
 | |
|             return
 | |
|         with f:
 | |
|             all_lines = f.readlines()
 | |
|             # start and end are 1-based, all_lines is 0-based;
 | |
|             # so [start-1:end] as a python slice gives us [start, end] as a
 | |
|             # closed interval
 | |
|             for i, line in enumerate(all_lines[start-1:end]):
 | |
|                 linestr = str(i+start)
 | |
|                 # Highlight current line:
 | |
|                 if i + start == lineno:
 | |
|                     linestr = '>' + linestr
 | |
|                 sys.stdout.write('%4s    %s' % (linestr, line))
 | |
| 
 | |
| 
 | |
| # ...and register the command:
 | |
| PyList()
 | |
| 
 | |
| def move_in_stack(move_up):
 | |
|     '''Move up or down the stack (for the py-up/py-down command)'''
 | |
|     # Important:
 | |
|     # The amount of frames that are printed out depends on how many frames are inlined
 | |
|     # in the same evaluation loop. As this command links directly the C stack with the
 | |
|     # Python stack, the results are sensitive to the number of inlined frames and this
 | |
|     # is likely to change between versions and optimizations.
 | |
|     frame = Frame.get_selected_python_frame()
 | |
|     if not frame:
 | |
|         print('Unable to locate python frame')
 | |
|         return
 | |
|     while frame:
 | |
|         if move_up:
 | |
|             iter_frame = frame.older()
 | |
|         else:
 | |
|             iter_frame = frame.newer()
 | |
| 
 | |
|         if not iter_frame:
 | |
|             break
 | |
| 
 | |
|         if iter_frame.is_python_frame():
 | |
|             # Result:
 | |
|             if iter_frame.select():
 | |
|                 iter_frame.print_summary()
 | |
|             return
 | |
| 
 | |
|         frame = iter_frame
 | |
| 
 | |
|     if move_up:
 | |
|         print('Unable to find an older python frame')
 | |
|     else:
 | |
|         print('Unable to find a newer python frame')
 | |
| 
 | |
| 
 | |
| class PyUp(gdb.Command):
 | |
|     'Select and print all python stack frame in the same eval loop starting from the one that called this one (if any)'
 | |
|     def __init__(self):
 | |
|         gdb.Command.__init__ (self,
 | |
|                               "py-up",
 | |
|                               gdb.COMMAND_STACK,
 | |
|                               gdb.COMPLETE_NONE)
 | |
| 
 | |
| 
 | |
|     def invoke(self, args, from_tty):
 | |
|         move_in_stack(move_up=True)
 | |
| 
 | |
| class PyDown(gdb.Command):
 | |
|     'Select and print all python stack frame in the same eval loop starting from the one called this one (if any)'
 | |
|     def __init__(self):
 | |
|         gdb.Command.__init__ (self,
 | |
|                               "py-down",
 | |
|                               gdb.COMMAND_STACK,
 | |
|                               gdb.COMPLETE_NONE)
 | |
| 
 | |
| 
 | |
|     def invoke(self, args, from_tty):
 | |
|         move_in_stack(move_up=False)
 | |
| 
 | |
| # Not all builds of gdb have gdb.Frame.select
 | |
| if hasattr(gdb.Frame, 'select'):
 | |
|     PyUp()
 | |
|     PyDown()
 | |
| 
 | |
| class PyBacktraceFull(gdb.Command):
 | |
|     'Display the current python frame and all the frames within its call stack (if any)'
 | |
|     def __init__(self):
 | |
|         gdb.Command.__init__ (self,
 | |
|                               "py-bt-full",
 | |
|                               gdb.COMMAND_STACK,
 | |
|                               gdb.COMPLETE_NONE)
 | |
| 
 | |
| 
 | |
|     def invoke(self, args, from_tty):
 | |
|         frame = Frame.get_selected_python_frame()
 | |
|         if not frame:
 | |
|             print('Unable to locate python frame')
 | |
|             return
 | |
| 
 | |
|         while frame:
 | |
|             if frame.is_python_frame():
 | |
|                 frame.print_summary()
 | |
|             frame = frame.older()
 | |
| 
 | |
| PyBacktraceFull()
 | |
| 
 | |
| class PyBacktrace(gdb.Command):
 | |
|     'Display the current python frame and all the frames within its call stack (if any)'
 | |
|     def __init__(self):
 | |
|         gdb.Command.__init__ (self,
 | |
|                               "py-bt",
 | |
|                               gdb.COMMAND_STACK,
 | |
|                               gdb.COMPLETE_NONE)
 | |
| 
 | |
| 
 | |
|     def invoke(self, args, from_tty):
 | |
|         frame = Frame.get_selected_python_frame()
 | |
|         if not frame:
 | |
|             print('Unable to locate python frame')
 | |
|             return
 | |
| 
 | |
|         sys.stdout.write('Traceback (most recent call first):\n')
 | |
|         while frame:
 | |
|             if frame.is_python_frame():
 | |
|                 frame.print_traceback()
 | |
|             frame = frame.older()
 | |
| 
 | |
| PyBacktrace()
 | |
| 
 | |
| class PyPrint(gdb.Command):
 | |
|     'Look up the given python variable name, and print it'
 | |
|     def __init__(self):
 | |
|         gdb.Command.__init__ (self,
 | |
|                               "py-print",
 | |
|                               gdb.COMMAND_DATA,
 | |
|                               gdb.COMPLETE_NONE)
 | |
| 
 | |
| 
 | |
|     def invoke(self, args, from_tty):
 | |
|         name = str(args)
 | |
| 
 | |
|         frame = Frame.get_selected_python_frame()
 | |
|         if not frame:
 | |
|             print('Unable to locate python frame')
 | |
|             return
 | |
| 
 | |
|         pyop_frame = frame.get_pyop()
 | |
|         if not pyop_frame:
 | |
|             print(UNABLE_READ_INFO_PYTHON_FRAME)
 | |
|             return
 | |
| 
 | |
|         pyop_var, scope = pyop_frame.get_var_by_name(name)
 | |
| 
 | |
|         if pyop_var:
 | |
|             print('%s %r = %s'
 | |
|                    % (scope,
 | |
|                       name,
 | |
|                       pyop_var.get_truncated_repr(MAX_OUTPUT_LEN)))
 | |
|         else:
 | |
|             print('%r not found' % name)
 | |
| 
 | |
| PyPrint()
 | |
| 
 | |
| class PyLocals(gdb.Command):
 | |
|     'Look up the given python variable name, and print it'
 | |
|     def __init__(self):
 | |
|         gdb.Command.__init__ (self,
 | |
|                               "py-locals",
 | |
|                               gdb.COMMAND_DATA,
 | |
|                               gdb.COMPLETE_NONE)
 | |
| 
 | |
| 
 | |
|     def invoke(self, args, from_tty):
 | |
|         name = str(args)
 | |
| 
 | |
|         frame = Frame.get_selected_python_frame()
 | |
|         if not frame:
 | |
|             print('Unable to locate python frame')
 | |
|             return
 | |
| 
 | |
|         pyop_frame = frame.get_pyop()
 | |
|         while True:
 | |
|             if not pyop_frame:
 | |
|                 print(UNABLE_READ_INFO_PYTHON_FRAME)
 | |
|             if pyop_frame.is_shim():
 | |
|                 break
 | |
| 
 | |
|             sys.stdout.write('Locals for %s\n' % (pyop_frame.co_name.proxyval(set())))
 | |
| 
 | |
|             for pyop_name, pyop_value in pyop_frame.iter_locals():
 | |
|                 print('%s = %s'
 | |
|                     % (pyop_name.proxyval(set()),
 | |
|                         pyop_value.get_truncated_repr(MAX_OUTPUT_LEN)))
 | |
| 
 | |
| 
 | |
|             pyop_frame = pyop_frame.previous()
 | |
| 
 | |
| PyLocals()
 |