Adding cython v0.20.2 in third-party.

third_party/cython/src/Cython/Debugger/libcython.py

+"""
+GDB extension that adds Cython support.
+"""
+
+from __future__ import with_statement
+
+import sys
+import textwrap
+import traceback
+import functools
+import itertools
+import collections
+
+import gdb
+
+try:
+    from lxml import etree
+    have_lxml = True
+except ImportError:
+    have_lxml = False
+    try:
+        # Python 2.5
+        from xml.etree import cElementTree as etree
+    except ImportError:
+        try:
+            # Python 2.5
+            from xml.etree import ElementTree as etree
+        except ImportError:
+            try:
+                # normal cElementTree install
+                import cElementTree as etree
+            except ImportError:
+                # normal ElementTree install
+                import elementtree.ElementTree as etree
+
+try:
+    import pygments.lexers
+    import pygments.formatters
+except ImportError:
+    pygments = None
+    sys.stderr.write("Install pygments for colorized source code.\n")
+
+if hasattr(gdb, 'string_to_argv'):
+    from gdb import string_to_argv
+else:
+    from shlex import split as string_to_argv
+
+from Cython.Debugger import libpython
+
+# C or Python type
+CObject = 'CObject'
+PythonObject = 'PythonObject'
+
+_data_types = dict(CObject=CObject, PythonObject=PythonObject)
+_filesystemencoding = sys.getfilesystemencoding() or 'UTF-8'
+
+# decorators
+
+def dont_suppress_errors(function):
+    "*sigh*, readline"
+    @functools.wraps(function)
+    def wrapper(*args, **kwargs):
+        try:
+            return function(*args, **kwargs)
+        except Exception:
+            traceback.print_exc()
+            raise
+
+    return wrapper
+
+def default_selected_gdb_frame(err=True):
+    def decorator(function):
+        @functools.wraps(function)
+        def wrapper(self, frame=None, *args, **kwargs):
+            try:
+                frame = frame or gdb.selected_frame()
+            except RuntimeError:
+                raise gdb.GdbError("No frame is currently selected.")
+
+            if err and frame.name() is None:
+                raise NoFunctionNameInFrameError()
+
+            return function(self, frame, *args, **kwargs)
+        return wrapper
+    return decorator
+
+def require_cython_frame(function):
+    @functools.wraps(function)
+    @require_running_program
+    def wrapper(self, *args, **kwargs):
+        frame = kwargs.get('frame') or gdb.selected_frame()
+        if not self.is_cython_function(frame):
+            raise gdb.GdbError('Selected frame does not correspond with a '
+                               'Cython function we know about.')
+        return function(self, *args, **kwargs)
+    return wrapper
+
+def dispatch_on_frame(c_command, python_command=None):
+    def decorator(function):
+        @functools.wraps(function)
+        def wrapper(self, *args, **kwargs):
+            is_cy = self.is_cython_function()
+            is_py = self.is_python_function()
+
+            if is_cy or (is_py and not python_command):
+                function(self, *args, **kwargs)
+            elif is_py:
+                gdb.execute(python_command)
+            elif self.is_relevant_function():
+                gdb.execute(c_command)
+            else:
+                raise gdb.GdbError("Not a function cygdb knows about. "
+                                   "Use the normal GDB commands instead.")
+
+        return wrapper
+    return decorator
+
+def require_running_program(function):
+    @functools.wraps(function)
+    def wrapper(*args, **kwargs):
+        try:
+            gdb.selected_frame()
+        except RuntimeError:
+            raise gdb.GdbError("No frame is currently selected.")
+
+        return function(*args, **kwargs)
+    return wrapper
+
+
+def gdb_function_value_to_unicode(function):
+    @functools.wraps(function)
+    def wrapper(self, string, *args, **kwargs):
+        if isinstance(string, gdb.Value):
+            string = string.string()
+
+        return function(self, string, *args, **kwargs)
+    return wrapper
+
+
+# Classes that represent the debug information
+# Don't rename the parameters of these classes, they come directly from the XML
+
+class CythonModule(object):
+    def __init__(self, module_name, filename, c_filename):
+        self.name = module_name
+        self.filename = filename
+        self.c_filename = c_filename
+        self.globals = {}
+        # {cython_lineno: min(c_linenos)}
+        self.lineno_cy2c = {}
+        # {c_lineno: cython_lineno}
+        self.lineno_c2cy = {}
+        self.functions = {}
+
+class CythonVariable(object):
+
+    def __init__(self, name, cname, qualified_name, type, lineno):
+        self.name = name
+        self.cname = cname
+        self.qualified_name = qualified_name
+        self.type = type
+        self.lineno = int(lineno)
+
+class CythonFunction(CythonVariable):
+    def __init__(self,
+                 module,
+                 name,
+                 cname,
+                 pf_cname,
+                 qualified_name,
+                 lineno,
+                 type=CObject,
+                 is_initmodule_function="False"):
+        super(CythonFunction, self).__init__(name,
+                                             cname,
+                                             qualified_name,
+                                             type,
+                                             lineno)
+        self.module = module
+        self.pf_cname = pf_cname
+        self.is_initmodule_function = is_initmodule_function == "True"
+        self.locals = {}
+        self.arguments = []
+        self.step_into_functions = set()
+
+
+# General purpose classes
+
+class CythonBase(object):
+
+    @default_selected_gdb_frame(err=False)
+    def is_cython_function(self, frame):
+        return frame.name() in self.cy.functions_by_cname
+
+    @default_selected_gdb_frame(err=False)
+    def is_python_function(self, frame):
+        """
+        Tells if a frame is associated with a Python function.
+        If we can't read the Python frame information, don't regard it as such.
+        """
+        if frame.name() == 'PyEval_EvalFrameEx':
+            pyframe = libpython.Frame(frame).get_pyop()
+            return pyframe and not pyframe.is_optimized_out()
+        return False
+
+    @default_selected_gdb_frame()
+    def get_c_function_name(self, frame):
+        return frame.name()
+
+    @default_selected_gdb_frame()
+    def get_c_lineno(self, frame):
+        return frame.find_sal().line
+
+    @default_selected_gdb_frame()
+    def get_cython_function(self, frame):
+        result = self.cy.functions_by_cname.get(frame.name())
+        if result is None:
+            raise NoCythonFunctionInFrameError()
+
+        return result
+
+    @default_selected_gdb_frame()
+    def get_cython_lineno(self, frame):
+        """
+        Get the current Cython line number. Returns 0 if there is no
+        correspondence between the C and Cython code.
+        """
+        cyfunc = self.get_cython_function(frame)
+        return cyfunc.module.lineno_c2cy.get(self.get_c_lineno(frame), 0)
+
+    @default_selected_gdb_frame()
+    def get_source_desc(self, frame):
+        filename = lineno = lexer = None
+        if self.is_cython_function(frame):
+            filename = self.get_cython_function(frame).module.filename
+            lineno = self.get_cython_lineno(frame)
+            if pygments:
+                lexer = pygments.lexers.CythonLexer(stripall=False)
+        elif self.is_python_function(frame):
+            pyframeobject = libpython.Frame(frame).get_pyop()
+
+            if not pyframeobject:
+                raise gdb.GdbError(
+                            'Unable to read information on python frame')
+
+            filename = pyframeobject.filename()
+            lineno = pyframeobject.current_line_num()
+
+            if pygments:
+                lexer = pygments.lexers.PythonLexer(stripall=False)
+        else:
+            symbol_and_line_obj = frame.find_sal()
+            if not symbol_and_line_obj or not symbol_and_line_obj.symtab:
+                filename = None
+                lineno = 0
+            else:
+                filename = symbol_and_line_obj.symtab.fullname()
+                lineno = symbol_and_line_obj.line
+                if pygments:
+                    lexer = pygments.lexers.CLexer(stripall=False)
+
+        return SourceFileDescriptor(filename, lexer), lineno
+
+    @default_selected_gdb_frame()
+    def get_source_line(self, frame):
+        source_desc, lineno = self.get_source_desc()
+        return source_desc.get_source(lineno)
+
+    @default_selected_gdb_frame()
+    def is_relevant_function(self, frame):
+        """
+        returns whether we care about a frame on the user-level when debugging
+        Cython code
+        """
+        name = frame.name()
+        older_frame = frame.older()
+        if self.is_cython_function(frame) or self.is_python_function(frame):
+            return True
+        elif older_frame and self.is_cython_function(older_frame):
+            # check for direct C function call from a Cython function
+            cython_func = self.get_cython_function(older_frame)
+            return name in cython_func.step_into_functions
+
+        return False
+
+    @default_selected_gdb_frame(err=False)
+    def print_stackframe(self, frame, index, is_c=False):
+        """
+        Print a C, Cython or Python stack frame and the line of source code
+        if available.
+        """
+        # do this to prevent the require_cython_frame decorator from
+        # raising GdbError when calling self.cy.cy_cvalue.invoke()
+        selected_frame = gdb.selected_frame()
+        frame.select()
+
+        try:
+            source_desc, lineno = self.get_source_desc(frame)
+        except NoFunctionNameInFrameError:
+            print '#%-2d Unknown Frame (compile with -g)' % index
+            return
+
+        if not is_c and self.is_python_function(frame):
+            pyframe = libpython.Frame(frame).get_pyop()
+            if pyframe is None or pyframe.is_optimized_out():
+                # print this python function as a C function
+                return self.print_stackframe(frame, index, is_c=True)
+
+            func_name = pyframe.co_name
+            func_cname = 'PyEval_EvalFrameEx'
+            func_args = []
+        elif self.is_cython_function(frame):
+            cyfunc = self.get_cython_function(frame)
+            f = lambda arg: self.cy.cy_cvalue.invoke(arg, frame=frame)
+
+            func_name = cyfunc.name
+            func_cname = cyfunc.cname
+            func_args = [] # [(arg, f(arg)) for arg in cyfunc.arguments]
+        else:
+            source_desc, lineno = self.get_source_desc(frame)
+            func_name = frame.name()
+            func_cname = func_name
+            func_args = []
+
+        try:
+            gdb_value = gdb.parse_and_eval(func_cname)
+        except RuntimeError:
+            func_address = 0
+        else:
+            # Seriously? Why is the address not an int?
+            func_address = int(str(gdb_value.address).split()[0], 0)
+
+        a = ', '.join('%s=%s' % (name, val) for name, val in func_args)
+        print '#%-2d 0x%016x in %s(%s)' % (index, func_address, func_name, a),
+
+        if source_desc.filename is not None:
+            print 'at %s:%s' % (source_desc.filename, lineno),
+
+        print
+
+        try:
+            print '    ' + source_desc.get_source(lineno)
+        except gdb.GdbError:
+            pass
+
+        selected_frame.select()
+
+    def get_remote_cython_globals_dict(self):
+        m = gdb.parse_and_eval('__pyx_m')
+
+        try:
+            PyModuleObject = gdb.lookup_type('PyModuleObject')
+        except RuntimeError:
+            raise gdb.GdbError(textwrap.dedent("""\
+                Unable to lookup type PyModuleObject, did you compile python
+                with debugging support (-g)?"""))
+
+        m = m.cast(PyModuleObject.pointer())
+        return m['md_dict']
+
+
+    def get_cython_globals_dict(self):
+        """
+        Get the Cython globals dict where the remote names are turned into
+        local strings.
+        """
+        remote_dict = self.get_remote_cython_globals_dict()
+        pyobject_dict = libpython.PyObjectPtr.from_pyobject_ptr(remote_dict)
+
+        result = {}
+        seen = set()
+        for k, v in pyobject_dict.iteritems():
+            result[k.proxyval(seen)] = v
+
+        return result
+
+    def print_gdb_value(self, name, value, max_name_length=None, prefix=''):
+        if libpython.pretty_printer_lookup(value):
+            typename = ''
+        else:
+            typename = '(%s) ' % (value.type,)
+
+        if max_name_length is None:
+            print '%s%s = %s%s' % (prefix, name, typename, value)
+        else:
+            print '%s%-*s = %s%s' % (prefix, max_name_length, name, typename,
+                                     value)
+
+    def is_initialized(self, cython_func, local_name):
+        cyvar = cython_func.locals[local_name]
+        cur_lineno = self.get_cython_lineno()
+
+        if '->' in cyvar.cname:
+            # Closed over free variable
+            if cur_lineno > cython_func.lineno:
+                if cyvar.type == PythonObject:
+                    return long(gdb.parse_and_eval(cyvar.cname))
+                return True
+            return False
+
+        return cur_lineno > cyvar.lineno
+
+
+class SourceFileDescriptor(object):
+    def __init__(self, filename, lexer, formatter=None):
+        self.filename = filename
+        self.lexer = lexer
+        self.formatter = formatter
+
+    def valid(self):
+        return self.filename is not None
+
+    def lex(self, code):
+        if pygments and self.lexer and parameters.colorize_code:
+            bg = parameters.terminal_background.value
+            if self.formatter is None:
+                formatter = pygments.formatters.TerminalFormatter(bg=bg)
+            else:
+                formatter = self.formatter
+
+            return pygments.highlight(code, self.lexer, formatter)
+
+        return code
+
+    def _get_source(self, start, stop, lex_source, mark_line, lex_entire):
+        with open(self.filename) as f:
+            # to provide "correct" colouring, the entire code needs to be
+            # lexed. However, this makes a lot of things terribly slow, so
+            # we decide not to. Besides, it's unlikely to matter.
+
+            if lex_source and lex_entire:
+                f = self.lex(f.read()).splitlines()
+
+            slice = itertools.islice(f, start - 1, stop - 1)
+
+            for idx, line in enumerate(slice):
+                if start + idx == mark_line:
+                    prefix = '>'
+                else:
+                    prefix = ' '
+
+                if lex_source and not lex_entire:
+                    line = self.lex(line)
+
+                yield '%s %4d    %s' % (prefix, start + idx, line.rstrip())
+
+    def get_source(self, start, stop=None, lex_source=True, mark_line=0,
+                   lex_entire=False):
+        exc = gdb.GdbError('Unable to retrieve source code')
+
+        if not self.filename:
+            raise exc
+
+        start = max(start, 1)
+        if stop is None:
+            stop = start + 1
+
+        try:
+            return '\n'.join(
+                self._get_source(start, stop, lex_source, mark_line, lex_entire))
+        except IOError:
+            raise exc
+
+
+# Errors
+
+class CyGDBError(gdb.GdbError):
+    """
+    Base class for Cython-command related erorrs
+    """
+
+    def __init__(self, *args):
+        args = args or (self.msg,)
+        super(CyGDBError, self).__init__(*args)
+
+class NoCythonFunctionInFrameError(CyGDBError):
+    """
+    raised when the user requests the current cython function, which is
+    unavailable
+    """
+    msg = "Current function is a function cygdb doesn't know about"
+
+class NoFunctionNameInFrameError(NoCythonFunctionInFrameError):
+    """
+    raised when the name of the C function could not be determined
+    in the current C stack frame
+    """
+    msg = ('C function name could not be determined in the current C stack '
+           'frame')
+
+
+# Parameters
+
+class CythonParameter(gdb.Parameter):
+    """
+    Base class for cython parameters
+    """
+
+    def __init__(self, name, command_class, parameter_class, default=None):
+        self.show_doc = self.set_doc = self.__class__.__doc__
+        super(CythonParameter, self).__init__(name, command_class,
+                                              parameter_class)
+        if default is not None:
+            self.value = default
+
+    def __nonzero__(self):
+        return bool(self.value)
+
+    __bool__ = __nonzero__ # python 3
+
+class CompleteUnqualifiedFunctionNames(CythonParameter):
+    """
+    Have 'cy break' complete unqualified function or method names.
+    """
+
+class ColorizeSourceCode(CythonParameter):
+    """
+    Tell cygdb whether to colorize source code.
+    """
+
+class TerminalBackground(CythonParameter):
+    """
+    Tell cygdb about the user's terminal background (light or dark).
+    """
+
+class CythonParameters(object):
+    """
+    Simple container class that might get more functionality in the distant
+    future (mostly to remind us that we're dealing with parameters).
+    """
+
+    def __init__(self):
+        self.complete_unqualified = CompleteUnqualifiedFunctionNames(
+            'cy_complete_unqualified',
+            gdb.COMMAND_BREAKPOINTS,
+            gdb.PARAM_BOOLEAN,
+            True)
+        self.colorize_code = ColorizeSourceCode(
+            'cy_colorize_code',
+            gdb.COMMAND_FILES,
+            gdb.PARAM_BOOLEAN,
+            True)
+        self.terminal_background = TerminalBackground(
+            'cy_terminal_background_color',
+            gdb.COMMAND_FILES,
+            gdb.PARAM_STRING,
+            "dark")
+
+parameters = CythonParameters()
+
+
+# Commands
+
+class CythonCommand(gdb.Command, CythonBase):
+    """
+    Base class for Cython commands
+    """
+
+    command_class = gdb.COMMAND_NONE
+
+    @classmethod
+    def _register(cls, clsname, args, kwargs):
+        if not hasattr(cls, 'completer_class'):
+            return cls(clsname, cls.command_class, *args, **kwargs)
+        else:
+            return cls(clsname, cls.command_class, cls.completer_class,
+                       *args, **kwargs)
+
+    @classmethod
+    def register(cls, *args, **kwargs):
+        alias = getattr(cls, 'alias', None)
+        if alias:
+            cls._register(cls.alias, args, kwargs)
+
+        return cls._register(cls.name, args, kwargs)
+
+
+class CyCy(CythonCommand):
+    """
+    Invoke a Cython command. Available commands are:
+
+        cy import
+        cy break
+        cy step
+        cy next
+        cy run
+        cy cont
+        cy finish
+        cy up
+        cy down
+        cy select
+        cy bt / cy backtrace
+        cy list
+        cy print
+        cy set
+        cy locals
+        cy globals
+        cy exec
+    """
+
+    name = 'cy'
+    command_class = gdb.COMMAND_NONE
+    completer_class = gdb.COMPLETE_COMMAND
+
+    def __init__(self, name, command_class, completer_class):
+        # keep the signature 2.5 compatible (i.e. do not use f(*a, k=v)
+        super(CythonCommand, self).__init__(name, command_class,
+                                            completer_class, prefix=True)
+
+        commands = dict(
+            # GDB commands
+            import_ = CyImport.register(),
+            break_ = CyBreak.register(),
+            step = CyStep.register(),
+            next = CyNext.register(),
+            run = CyRun.register(),
+            cont = CyCont.register(),
+            finish = CyFinish.register(),
+            up = CyUp.register(),
+            down = CyDown.register(),
+            select = CySelect.register(),
+            bt = CyBacktrace.register(),
+            list = CyList.register(),
+            print_ = CyPrint.register(),
+            locals = CyLocals.register(),
+            globals = CyGlobals.register(),
+            exec_ = libpython.FixGdbCommand('cy exec', '-cy-exec'),
+            _exec = CyExec.register(),
+            set = CySet.register(),
+
+            # GDB functions
+            cy_cname = CyCName('cy_cname'),
+            cy_cvalue = CyCValue('cy_cvalue'),
+            cy_lineno = CyLine('cy_lineno'),
+            cy_eval = CyEval('cy_eval'),
+        )
+
+        for command_name, command in commands.iteritems():
+            command.cy = self
+            setattr(self, command_name, command)
+
+        self.cy = self
+
+        # Cython module namespace
+        self.cython_namespace = {}
+
+        # maps (unique) qualified function names (e.g.
+        # cythonmodule.ClassName.method_name) to the CythonFunction object
+        self.functions_by_qualified_name = {}
+
+        # unique cnames of Cython functions
+        self.functions_by_cname = {}
+
+        # map function names like method_name to a list of all such
+        # CythonFunction objects
+        self.functions_by_name = collections.defaultdict(list)
+
+
+class CyImport(CythonCommand):
+    """
+    Import debug information outputted by the Cython compiler
+    Example: cy import FILE...
+    """
+
+    name = 'cy import'
+    command_class = gdb.COMMAND_STATUS
+    completer_class = gdb.COMPLETE_FILENAME
+
+    def invoke(self, args, from_tty):
+        args = args.encode(_filesystemencoding)
+        for arg in string_to_argv(args):
+            try:
+                f = open(arg)
+            except OSError, e:
+                raise gdb.GdbError('Unable to open file %r: %s' %
+                                                (args, e.args[1]))
+
+            t = etree.parse(f)
+
+            for module in t.getroot():
+                cython_module = CythonModule(**module.attrib)
+                self.cy.cython_namespace[cython_module.name] = cython_module
+
+                for variable in module.find('Globals'):
+                    d = variable.attrib
+                    cython_module.globals[d['name']] = CythonVariable(**d)
+
+                for function in module.find('Functions'):
+                    cython_function = CythonFunction(module=cython_module,
+                                                     **function.attrib)
+
+                    # update the global function mappings
+                    name = cython_function.name
+                    qname = cython_function.qualified_name
+
+                    self.cy.functions_by_name[name].append(cython_function)
+                    self.cy.functions_by_qualified_name[
+                        cython_function.qualified_name] = cython_function
+                    self.cy.functions_by_cname[
+                        cython_function.cname] = cython_function
+
+                    d = cython_module.functions[qname] = cython_function
+
+                    for local in function.find('Locals'):
+                        d = local.attrib
+                        cython_function.locals[d['name']] = CythonVariable(**d)
+
+                    for step_into_func in function.find('StepIntoFunctions'):
+                        d = step_into_func.attrib
+                        cython_function.step_into_functions.add(d['name'])
+
+                    cython_function.arguments.extend(
+                        funcarg.tag for funcarg in function.find('Arguments'))
+
+                for marker in module.find('LineNumberMapping'):
+                    cython_lineno = int(marker.attrib['cython_lineno'])
+                    c_linenos = map(int, marker.attrib['c_linenos'].split())
+                    cython_module.lineno_cy2c[cython_lineno] = min(c_linenos)
+                    for c_lineno in c_linenos:
+                        cython_module.lineno_c2cy[c_lineno] = cython_lineno
+
+
+class CyBreak(CythonCommand):
+    """
+    Set a breakpoint for Cython code using Cython qualified name notation, e.g.:
+
+        cy break cython_modulename.ClassName.method_name...
+
+    or normal notation:
+
+        cy break function_or_method_name...
+
+    or for a line number:
+
+        cy break cython_module:lineno...
+
+    Set a Python breakpoint:
+        Break on any function or method named 'func' in module 'modname'
+
+            cy break -p modname.func...
+
+        Break on any function or method named 'func'
+
+            cy break -p func...
+    """
+
+    name = 'cy break'
+    command_class = gdb.COMMAND_BREAKPOINTS
+
+    def _break_pyx(self, name):
+        modulename, _, lineno = name.partition(':')
+        lineno = int(lineno)
+        if modulename:
+            cython_module = self.cy.cython_namespace[modulename]
+        else:
+            cython_module = self.get_cython_function().module
+
+        if lineno in cython_module.lineno_cy2c:
+            c_lineno = cython_module.lineno_cy2c[lineno]
+            breakpoint = '%s:%s' % (cython_module.c_filename, c_lineno)
+            gdb.execute('break ' + breakpoint)
+        else:
+            raise gdb.GdbError("Not a valid line number. "
+                               "Does it contain actual code?")
+
+    def _break_funcname(self, funcname):
+        func = self.cy.functions_by_qualified_name.get(funcname)
+
+        if func and func.is_initmodule_function:
+            func = None
+
+        break_funcs = [func]
+
+        if not func:
+            funcs = self.cy.functions_by_name.get(funcname) or []
+            funcs = [f for f in funcs if not f.is_initmodule_function]
+
+            if not funcs:
+                gdb.execute('break ' + funcname)
+                return
+
+            if len(funcs) > 1:
+                # multiple functions, let the user pick one
+                print 'There are multiple such functions:'
+                for idx, func in enumerate(funcs):
+                    print '%3d) %s' % (idx, func.qualified_name)
+
+                while True:
+                    try:
+                        result = raw_input(
+                            "Select a function, press 'a' for all "
+                            "functions or press 'q' or '^D' to quit: ")
+                    except EOFError:
+                        return
+                    else:
+                        if result.lower() == 'q':
+                            return
+                        elif result.lower() == 'a':
+                            break_funcs = funcs
+                            break
+                        elif (result.isdigit() and
+                            0 <= int(result) < len(funcs)):
+                            break_funcs = [funcs[int(result)]]
+                            break
+                        else:
+                            print 'Not understood...'
+            else:
+                break_funcs = [funcs[0]]
+
+        for func in break_funcs:
+            gdb.execute('break %s' % func.cname)
+            if func.pf_cname:
+                gdb.execute('break %s' % func.pf_cname)
+
+    def invoke(self, function_names, from_tty):
+        argv = string_to_argv(function_names.encode('UTF-8'))
+        if function_names.startswith('-p'):
+            argv = argv[1:]
+            python_breakpoints = True
+        else:
+            python_breakpoints = False
+
+        for funcname in argv:
+            if python_breakpoints:
+                gdb.execute('py-break %s' % funcname)
+            elif ':' in funcname:
+                self._break_pyx(funcname)
+            else:
+                self._break_funcname(funcname)
+
+    @dont_suppress_errors
+    def complete(self, text, word):
+        # Filter init-module functions (breakpoints can be set using
+        # modulename:linenumber).
+        names =  [n for n, L in self.cy.functions_by_name.iteritems()
+                        if any(not f.is_initmodule_function for f in L)]
+        qnames = [n for n, f in self.cy.functions_by_qualified_name.iteritems()
+                        if not f.is_initmodule_function]
+
+        if parameters.complete_unqualified:
+            all_names = itertools.chain(qnames, names)
+        else:
+            all_names = qnames
+
+        words = text.strip().split()
+        if not words or '.' not in words[-1]:
+            # complete unqualified
+            seen = set(text[:-len(word)].split())
+            return [n for n in all_names
+                          if n.startswith(word) and n not in seen]
+
+        # complete qualified name
+        lastword = words[-1]
+        compl = [n for n in qnames if n.startswith(lastword)]
+
+        if len(lastword) > len(word):
+            # readline sees something (e.g. a '.') as a word boundary, so don't
+            # "recomplete" this prefix
+            strip_prefix_length = len(lastword) - len(word)
+            compl = [n[strip_prefix_length:] for n in compl]
+
+        return compl
+
+
+class CythonInfo(CythonBase, libpython.PythonInfo):
+    """
+    Implementation of the interface dictated by libpython.LanguageInfo.
+    """
+
+    def lineno(self, frame):
+        # Take care of the Python and Cython levels. We need to care for both
+        # as we can't simply dispath to 'py-step', since that would work for
+        # stepping through Python code, but it would not step back into Cython-
+        # related code. The C level should be dispatched to the 'step' command.
+        if self.is_cython_function(frame):
+            return self.get_cython_lineno(frame)
+        return super(CythonInfo, self).lineno(frame)
+
+    def get_source_line(self, frame):
+        try:
+            line = super(CythonInfo, self).get_source_line(frame)
+        except gdb.GdbError:
+            return None
+        else:
+            return line.strip() or None
+
+    def exc_info(self, frame):
+        if self.is_python_function:
+            return super(CythonInfo, self).exc_info(frame)
+
+    def runtime_break_functions(self):
+        if self.is_cython_function():
+            return self.get_cython_function().step_into_functions
+        return ()
+
+    def static_break_functions(self):
+        result = ['PyEval_EvalFrameEx']
+        result.extend(self.cy.functions_by_cname)
+        return result
+
+
+class CythonExecutionControlCommand(CythonCommand,
+                                    libpython.ExecutionControlCommandBase):
+
+    @classmethod
+    def register(cls):
+        return cls(cls.name, cython_info)
+
+
+class CyStep(CythonExecutionControlCommand, libpython.PythonStepperMixin):
+    "Step through Cython, Python or C code."
+
+    name = 'cy -step'
+    stepinto = True
+
+    def invoke(self, args, from_tty):
+        if self.is_python_function():
+            self.python_step(self.stepinto)
+        elif not self.is_cython_function():
+            if self.stepinto:
+                command = 'step'
+            else:
+                command = 'next'
+
+            self.finish_executing(gdb.execute(command, to_string=True))
+        else:
+            self.step(stepinto=self.stepinto)
+
+
+class CyNext(CyStep):
+    "Step-over Cython, Python or C code."
+
+    name = 'cy -next'
+    stepinto = False
+
+
+class CyRun(CythonExecutionControlCommand):
+    """
+    Run a Cython program. This is like the 'run' command, except that it
+    displays Cython or Python source lines as well
+    """
+
+    name = 'cy run'
+
+    invoke = CythonExecutionControlCommand.run
+
+
+class CyCont(CythonExecutionControlCommand):
+    """
+    Continue a Cython program. This is like the 'run' command, except that it
+    displays Cython or Python source lines as well.
+    """
+
+    name = 'cy cont'
+    invoke = CythonExecutionControlCommand.cont
+
+
+class CyFinish(CythonExecutionControlCommand):
+    """
+    Execute until the function returns.
+    """
+    name = 'cy finish'
+
+    invoke = CythonExecutionControlCommand.finish
+
+
+class CyUp(CythonCommand):
+    """
+    Go up a Cython, Python or relevant C frame.
+    """
+    name = 'cy up'
+    _command = 'up'
+
+    def invoke(self, *args):
+        try:
+            gdb.execute(self._command, to_string=True)
+            while not self.is_relevant_function(gdb.selected_frame()):
+                gdb.execute(self._command, to_string=True)
+        except RuntimeError, e:
+            raise gdb.GdbError(*e.args)
+
+        frame = gdb.selected_frame()
+        index = 0
+        while frame:
+            frame = frame.older()
+            index += 1
+
+        self.print_stackframe(index=index - 1)
+
+
+class CyDown(CyUp):
+    """
+    Go down a Cython, Python or relevant C frame.
+    """
+
+    name = 'cy down'
+    _command = 'down'
+
+
+class CySelect(CythonCommand):
+    """
+    Select a frame. Use frame numbers as listed in `cy backtrace`.
+    This command is useful because `cy backtrace` prints a reversed backtrace.
+    """
+
+    name = 'cy select'
+
+    def invoke(self, stackno, from_tty):
+        try:
+            stackno = int(stackno)
+        except ValueError:
+            raise gdb.GdbError("Not a valid number: %r" % (stackno,))
+
+        frame = gdb.selected_frame()
+        while frame.newer():
+            frame = frame.newer()
+
+        stackdepth = libpython.stackdepth(frame)
+
+        try:
+            gdb.execute('select %d' % (stackdepth - stackno - 1,))
+        except RuntimeError, e:
+            raise gdb.GdbError(*e.args)
+
+
+class CyBacktrace(CythonCommand):
+    'Print the Cython stack'
+
+    name = 'cy bt'
+    alias = 'cy backtrace'
+    command_class = gdb.COMMAND_STACK
+    completer_class = gdb.COMPLETE_NONE
+
+    @require_running_program
+    def invoke(self, args, from_tty):
+        # get the first frame
+        frame = gdb.selected_frame()
+        while frame.older():
+            frame = frame.older()
+
+        print_all = args == '-a'
+
+        index = 0
+        while frame:
+            try:
+                is_relevant = self.is_relevant_function(frame)
+            except CyGDBError:
+                is_relevant = False
+
+            if print_all or is_relevant:
+                self.print_stackframe(frame, index)
+
+            index += 1
+            frame = frame.newer()
+
+
+class CyList(CythonCommand):
+    """
+    List Cython source code. To disable to customize colouring see the cy_*
+    parameters.
+    """
+
+    name = 'cy list'
+    command_class = gdb.COMMAND_FILES
+    completer_class = gdb.COMPLETE_NONE
+
+    # @dispatch_on_frame(c_command='list')
+    def invoke(self, _, from_tty):
+        sd, lineno = self.get_source_desc()
+        source = sd.get_source(lineno - 5, lineno + 5, mark_line=lineno,
+                               lex_entire=True)
+        print source
+
+
+class CyPrint(CythonCommand):
+    """
+    Print a Cython variable using 'cy-print x' or 'cy-print module.function.x'
+    """
+
+    name = 'cy print'
+    command_class = gdb.COMMAND_DATA
+
+    def invoke(self, name, from_tty, max_name_length=None):
+        if self.is_python_function():
+            return gdb.execute('py-print ' + name)
+        elif self.is_cython_function():
+            value = self.cy.cy_cvalue.invoke(name.lstrip('*'))
+            for c in name:
+                if c == '*':
+                    value = value.dereference()
+                else:
+                    break
+
+            self.print_gdb_value(name, value, max_name_length)
+        else:
+            gdb.execute('print ' + name)
+
+    def complete(self):
+        if self.is_cython_function():
+            f = self.get_cython_function()
+            return list(itertools.chain(f.locals, f.globals))
+        else:
+            return []
+
+
+sortkey = lambda (name, value): name.lower()
+
+class CyLocals(CythonCommand):
+    """
+    List the locals from the current Cython frame.
+    """
+
+    name = 'cy locals'
+    command_class = gdb.COMMAND_STACK
+    completer_class = gdb.COMPLETE_NONE
+
+    @dispatch_on_frame(c_command='info locals', python_command='py-locals')
+    def invoke(self, args, from_tty):
+        cython_function = self.get_cython_function()
+
+        if cython_function.is_initmodule_function:
+            self.cy.globals.invoke(args, from_tty)
+            return
+
+        local_cython_vars = cython_function.locals
+        max_name_length = len(max(local_cython_vars, key=len))
+        for name, cyvar in sorted(local_cython_vars.iteritems(), key=sortkey):
+            if self.is_initialized(self.get_cython_function(), cyvar.name):
+                value = gdb.parse_and_eval(cyvar.cname)
+                if not value.is_optimized_out:
+                    self.print_gdb_value(cyvar.name, value,
+                                         max_name_length, '')
+
+
+class CyGlobals(CyLocals):
+    """
+    List the globals from the current Cython module.
+    """
+
+    name = 'cy globals'
+    command_class = gdb.COMMAND_STACK
+    completer_class = gdb.COMPLETE_NONE
+
+    @dispatch_on_frame(c_command='info variables', python_command='py-globals')
+    def invoke(self, args, from_tty):
+        global_python_dict = self.get_cython_globals_dict()
+        module_globals = self.get_cython_function().module.globals
+
+        max_globals_len = 0
+        max_globals_dict_len = 0
+        if module_globals:
+            max_globals_len = len(max(module_globals, key=len))
+        if global_python_dict:
+            max_globals_dict_len = len(max(global_python_dict))
+
+        max_name_length = max(max_globals_len, max_globals_dict_len)
+
+        seen = set()
+        print 'Python globals:'
+        for k, v in sorted(global_python_dict.iteritems(), key=sortkey):
+            v = v.get_truncated_repr(libpython.MAX_OUTPUT_LEN)
+            seen.add(k)
+            print '    %-*s = %s' % (max_name_length, k, v)
+
+        print 'C globals:'
+        for name, cyvar in sorted(module_globals.iteritems(), key=sortkey):
+            if name not in seen:
+                try:
+                    value = gdb.parse_and_eval(cyvar.cname)
+                except RuntimeError:
+                    pass
+                else:
+                    if not value.is_optimized_out:
+                        self.print_gdb_value(cyvar.name, value,
+                                             max_name_length, '    ')
+
+
+
+class EvaluateOrExecuteCodeMixin(object):
+    """
+    Evaluate or execute Python code in a Cython or Python frame. The 'evalcode'
+    method evaluations Python code, prints a traceback if an exception went
+    uncaught, and returns any return value as a gdb.Value (NULL on exception).
+    """
+
+    def _fill_locals_dict(self, executor, local_dict_pointer):
+        "Fill a remotely allocated dict with values from the Cython C stack"
+        cython_func = self.get_cython_function()
+
+        for name, cyvar in cython_func.locals.iteritems():
+            if (cyvar.type == PythonObject and
+                self.is_initialized(cython_func, name)):
+
+                try:
+                    val = gdb.parse_and_eval(cyvar.cname)
+                except RuntimeError:
+                    continue
+                else:
+                    if val.is_optimized_out:
+                        continue
+
+                pystringp = executor.alloc_pystring(name)
+                code = '''
+                    (PyObject *) PyDict_SetItem(
+                        (PyObject *) %d,
+                        (PyObject *) %d,
+                        (PyObject *) %s)
+                ''' % (local_dict_pointer, pystringp, cyvar.cname)
+
+                try:
+                    if gdb.parse_and_eval(code) < 0:
+                        gdb.parse_and_eval('PyErr_Print()')
+                        raise gdb.GdbError("Unable to execute Python code.")
+                finally:
+                    # PyDict_SetItem doesn't steal our reference
+                    executor.xdecref(pystringp)
+
+    def _find_first_cython_or_python_frame(self):
+        frame = gdb.selected_frame()
+        while frame:
+            if (self.is_cython_function(frame) or
+                self.is_python_function(frame)):
+                frame.select()
+                return frame
+
+            frame = frame.older()
+
+        raise gdb.GdbError("There is no Cython or Python frame on the stack.")
+
+
+    def _evalcode_cython(self, executor, code, input_type):
+        with libpython.FetchAndRestoreError():
+            # get the dict of Cython globals and construct a dict in the
+            # inferior with Cython locals
+            global_dict = gdb.parse_and_eval(
+                '(PyObject *) PyModule_GetDict(__pyx_m)')
+            local_dict = gdb.parse_and_eval('(PyObject *) PyDict_New()')
+
+            try:
+                self._fill_locals_dict(executor,
+                                       libpython.pointervalue(local_dict))
+                result = executor.evalcode(code, input_type, global_dict,
+                                           local_dict)
+            finally:
+                executor.xdecref(libpython.pointervalue(local_dict))
+
+        return result
+
+    def evalcode(self, code, input_type):
+        """
+        Evaluate `code` in a Python or Cython stack frame using the given
+        `input_type`.
+        """
+        frame = self._find_first_cython_or_python_frame()
+        executor = libpython.PythonCodeExecutor()
+        if self.is_python_function(frame):
+            return libpython._evalcode_python(executor, code, input_type)
+        return self._evalcode_cython(executor, code, input_type)
+
+
+class CyExec(CythonCommand, libpython.PyExec, EvaluateOrExecuteCodeMixin):
+    """
+    Execute Python code in the nearest Python or Cython frame.
+    """
+
+    name = '-cy-exec'
+    command_class = gdb.COMMAND_STACK
+    completer_class = gdb.COMPLETE_NONE
+
+    def invoke(self, expr, from_tty):
+        expr, input_type = self.readcode(expr)
+        executor = libpython.PythonCodeExecutor()
+        executor.xdecref(self.evalcode(expr, executor.Py_single_input))
+
+
+class CySet(CythonCommand):
+    """
+    Set a Cython variable to a certain value
+
+        cy set my_cython_c_variable = 10
+        cy set my_cython_py_variable = $cy_eval("{'doner': 'kebab'}")
+
+    This is equivalent to
+
+        set $cy_value("my_cython_variable") = 10
+    """
+
+    name = 'cy set'
+    command_class = gdb.COMMAND_DATA
+    completer_class = gdb.COMPLETE_NONE
+
+    @require_cython_frame
+    def invoke(self, expr, from_tty):
+        name_and_expr = expr.split('=', 1)
+        if len(name_and_expr) != 2:
+            raise gdb.GdbError("Invalid expression. Use 'cy set var = expr'.")
+
+        varname, expr = name_and_expr
+        cname = self.cy.cy_cname.invoke(varname.strip())
+        gdb.execute("set %s = %s" % (cname, expr))
+
+
+# Functions
+
+class CyCName(gdb.Function, CythonBase):
+    """
+    Get the C name of a Cython variable in the current context.
+    Examples:
+
+        print $cy_cname("function")
+        print $cy_cname("Class.method")
+        print $cy_cname("module.function")
+    """
+
+    @require_cython_frame
+    @gdb_function_value_to_unicode
+    def invoke(self, cyname, frame=None):
+        frame = frame or gdb.selected_frame()
+        cname = None
+
+        if self.is_cython_function(frame):
+            cython_function = self.get_cython_function(frame)
+            if cyname in cython_function.locals:
+                cname = cython_function.locals[cyname].cname
+            elif cyname in cython_function.module.globals:
+                cname = cython_function.module.globals[cyname].cname
+            else:
+                qname = '%s.%s' % (cython_function.module.name, cyname)
+                if qname in cython_function.module.functions:
+                    cname = cython_function.module.functions[qname].cname
+
+        if not cname:
+            cname = self.cy.functions_by_qualified_name.get(cyname)
+
+        if not cname:
+            raise gdb.GdbError('No such Cython variable: %s' % cyname)
+
+        return cname
+
+
+class CyCValue(CyCName):
+    """
+    Get the value of a Cython variable.
+    """
+
+    @require_cython_frame
+    @gdb_function_value_to_unicode
+    def invoke(self, cyname, frame=None):
+        globals_dict = self.get_cython_globals_dict()
+        cython_function = self.get_cython_function(frame)
+
+        if self.is_initialized(cython_function, cyname):
+            cname = super(CyCValue, self).invoke(cyname, frame=frame)
+            return gdb.parse_and_eval(cname)
+        elif cyname in globals_dict:
+            return globals_dict[cyname]._gdbval
+        else:
+            raise gdb.GdbError("Variable %s is not initialized." % cyname)
+
+
+class CyLine(gdb.Function, CythonBase):
+    """
+    Get the current Cython line.
+    """
+
+    @require_cython_frame
+    def invoke(self):
+        return self.get_cython_lineno()
+
+
+class CyEval(gdb.Function, CythonBase, EvaluateOrExecuteCodeMixin):
+    """
+    Evaluate Python code in the nearest Python or Cython frame and return
+    """
+
+    @gdb_function_value_to_unicode
+    def invoke(self, python_expression):
+        input_type = libpython.PythonCodeExecutor.Py_eval_input
+        return self.evalcode(python_expression, input_type)
+
+
+cython_info = CythonInfo()
+cy = CyCy.register()
+cython_info.cy = cy
+
+def register_defines():
+    libpython.source_gdb_script(textwrap.dedent("""\
+        define cy step
+        cy -step
+        end
+
+        define cy next
+        cy -next
+        end
+
+        document cy step
+        %s
+        end
+
+        document cy next
+        %s
+        end
+    """) % (CyStep.__doc__, CyNext.__doc__))
+
+register_defines()