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pyfields.py
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| $ python foo.py & | |
| [1] 21377 | |
| $ gdb -p 21377 | |
| GNU gdb (GDB) Fedora 7.7.1-17.fc20 | |
| [... gdb loading messages ...] | |
| 0x00007f9a09af46e3 in __select_nocancel () at ../sysdeps/unix/syscall-template.S:81 | |
| 81 T_PSEUDO (SYSCALL_SYMBOL, SYSCALL_NAME, SYSCALL_NARGS) | |
| (gdb) py-bt | |
| #4 Frame 0x22d9c70, for file foo.py, line 12, in forever () | |
| sleep(1) | |
| #7 Frame 0x224f830, for file foo.py, line 14, in <module> () | |
| forever() | |
| (gdb) py-print f | |
| global 'f' = <Foo(foo=1) at remote 0x7f9a0abba830> | |
| (gdb) py-print f.foo | |
| 'f.foo' not found | |
| (gdb) source pyfields.py | |
| (gdb) py-fields f.foo | |
| global 'foo' = 1 | |
| (gdb) quit | |
| A debugging session is active. | |
| Inferior 1 [process 21377] will be detached. | |
| Quit anyway? (y or n) y | |
| Detaching from program: /usr/bin/python2.7, process 21377 | |
| $ exit | |
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| from time import sleep | |
| class Foo: | |
| def __init__(self): | |
| self.foo = 1 | |
| f = Foo() | |
| def forever(): | |
| while f.foo == 1: | |
| sleep(1) | |
| forever() |
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| class PyPrintFields(gdb.Command): | |
| 'Look up the given python variable name, and print it' | |
| def __init__(self): | |
| gdb.Command.__init__ (self, | |
| "py-fields", | |
| 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 to read information on python frame' | |
| return | |
| def get_var_dict(v): | |
| if isinstance(v, PyInstanceObjectPtr): | |
| return v.pyop_field('in_dict') | |
| elif isinstance(v, HeapTypeObjectPtr): | |
| return v.get_attr_dict() | |
| else: | |
| return {} | |
| parent = None | |
| fields = name.split('.') | |
| for name in fields: | |
| if parent is None: | |
| pyop_var, scope = pyop_frame.get_var_by_name(name) | |
| else: | |
| for k, pyop_var in get_var_dict(parent).iteritems(): | |
| if str(k) == name: | |
| break | |
| else: | |
| print "Can't find field %s of %s" % (name, parent) | |
| return | |
| parent = pyop_var | |
| if pyop_var: | |
| print ('%s %r = %s' | |
| % (scope, | |
| name, | |
| pyop_var.get_truncated_repr(MAX_OUTPUT_LEN))) | |
| else: | |
| print '%r not found' % name | |
| PyPrintFields() |
Here is a replacement for invoke that works (at least somewhat) on python3:
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 to read information on python frame'
return
def get_var_dict(v):
if isinstance(v, HeapTypeObjectPtr):
return v.get_attr_dict()
elif 'pyop_field' in v:
return v.pyop_field('in_dict')
else:
return {}
parent = None
fields = name.split('.')
for name in fields:
if parent is None:
pyop_var, scope = pyop_frame.get_var_by_name(name)
else:
pyop_var = next((_v for _k, _v in get_var_dict(parent).iteritems() if str(_k.proxyval(set())) == name), None)
if not pyop_var:
names = [str(_k.proxyval(set())) for _k, _v in get_var_dict(parent).iteritems()]
print "Can't find field %s of %s. Available keys: %s" % (name, parent, names)
return
parent = pyop_var
if pyop_var:
print ('%s %r = %s'
% (scope,
name,
pyop_var.get_truncated_repr(MAX_OUTPUT_LEN)))
else:
print '%r not found' % name
Hey that worked! Thanks a lot @PhracturedBlue!
Here's a full version of pyfields.py including @PhracturedBlue's change, as well as switching from print statements to print function:
class PyPrintFields(gdb.Command):
'Look up the given python variable name, and print it'
def __init__(self):
gdb.Command.__init__ (self,
"py-fields",
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 to read information on python frame')
return
def get_var_dict(v):
if isinstance(v, HeapTypeObjectPtr):
return v.get_attr_dict()
elif 'pyop_field' in v:
return v.pyop_field('in_dict')
else:
return {}
parent = None
fields = name.split('.')
for name in fields:
if parent is None:
pyop_var, scope = pyop_frame.get_var_by_name(name)
else:
pyop_var = next((_v for _k, _v in get_var_dict(parent).iteritems() if str(_k.proxyval(set())) == name), None)
if not pyop_var:
names = [str(_k.proxyval(set())) for _k, _v in get_var_dict(parent).iteritems()]
print("Can't find field %s of %s. Available keys: %s" % (name, parent, names))
return
parent = pyop_var
if pyop_var:
print ('%s %r = %s'
% (scope,
name,
pyop_var.get_truncated_repr(MAX_OUTPUT_LEN)))
else:
print('%r not found' % name)
PyPrintFields()
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Any ideas why this wouldn't work in python3? I get this error