| """Debugger basics""" | |
| import fnmatch | |
| import sys | |
| import os | |
| import types | |
| __all__ = ["BdbQuit","Bdb","Breakpoint"] | |
| class BdbQuit(Exception): | |
| """Exception to give up completely""" | |
| class Bdb: | |
| """Generic Python debugger base class. | |
| This class takes care of details of the trace facility; | |
| a derived class should implement user interaction. | |
| The standard debugger class (pdb.Pdb) is an example. | |
| """ | |
| def __init__(self, skip=None): | |
| self.skip = set(skip) if skip else None | |
| self.breaks = {} | |
| self.fncache = {} | |
| def canonic(self, filename): | |
| if filename == "<" + filename[1:-1] + ">": | |
| return filename | |
| canonic = self.fncache.get(filename) | |
| if not canonic: | |
| canonic = os.path.abspath(filename) | |
| canonic = os.path.normcase(canonic) | |
| self.fncache[filename] = canonic | |
| return canonic | |
| def reset(self): | |
| import linecache | |
| linecache.checkcache() | |
| self.botframe = None | |
| self._set_stopinfo(None, None) | |
| def trace_dispatch(self, frame, event, arg): | |
| if self.quitting: | |
| return # None | |
| if event == 'line': | |
| return self.dispatch_line(frame) | |
| if event == 'call': | |
| return self.dispatch_call(frame, arg) | |
| if event == 'return': | |
| return self.dispatch_return(frame, arg) | |
| if event == 'exception': | |
| return self.dispatch_exception(frame, arg) | |
| if event == 'c_call': | |
| return self.trace_dispatch | |
| if event == 'c_exception': | |
| return self.trace_dispatch | |
| if event == 'c_return': | |
| return self.trace_dispatch | |
| print 'bdb.Bdb.dispatch: unknown debugging event:', repr(event) | |
| return self.trace_dispatch | |
| def dispatch_line(self, frame): | |
| if self.stop_here(frame) or self.break_here(frame): | |
| self.user_line(frame) | |
| if self.quitting: raise BdbQuit | |
| return self.trace_dispatch | |
| def dispatch_call(self, frame, arg): | |
| # XXX 'arg' is no longer used | |
| if self.botframe is None: | |
| # First call of dispatch since reset() | |
| self.botframe = frame.f_back # (CT) Note that this may also be None! | |
| return self.trace_dispatch | |
| if not (self.stop_here(frame) or self.break_anywhere(frame)): | |
| # No need to trace this function | |
| return # None | |
| self.user_call(frame, arg) | |
| if self.quitting: raise BdbQuit | |
| return self.trace_dispatch | |
| def dispatch_return(self, frame, arg): | |
| if self.stop_here(frame) or frame == self.returnframe: | |
| self.user_return(frame, arg) | |
| if self.quitting: raise BdbQuit | |
| return self.trace_dispatch | |
| def dispatch_exception(self, frame, arg): | |
| if self.stop_here(frame): | |
| self.user_exception(frame, arg) | |
| if self.quitting: raise BdbQuit | |
| return self.trace_dispatch | |
| # Normally derived classes don't override the following | |
| # methods, but they may if they want to redefine the | |
| # definition of stopping and breakpoints. | |
| def is_skipped_module(self, module_name): | |
| for pattern in self.skip: | |
| if fnmatch.fnmatch(module_name, pattern): | |
| return True | |
| return False | |
| def stop_here(self, frame): | |
| # (CT) stopframe may now also be None, see dispatch_call. | |
| # (CT) the former test for None is therefore removed from here. | |
| if self.skip and \ | |
| self.is_skipped_module(frame.f_globals.get('__name__')): | |
| return False | |
| if frame is self.stopframe: | |
| if self.stoplineno == -1: | |
| return False | |
| return frame.f_lineno >= self.stoplineno | |
| while frame is not None and frame is not self.stopframe: | |
| if frame is self.botframe: | |
| return True | |
| frame = frame.f_back | |
| return False | |
| def break_here(self, frame): | |
| filename = self.canonic(frame.f_code.co_filename) | |
| if not filename in self.breaks: | |
| return False | |
| lineno = frame.f_lineno | |
| if not lineno in self.breaks[filename]: | |
| # The line itself has no breakpoint, but maybe the line is the | |
| # first line of a function with breakpoint set by function name. | |
| lineno = frame.f_code.co_firstlineno | |
| if not lineno in self.breaks[filename]: | |
| return False | |
| # flag says ok to delete temp. bp | |
| (bp, flag) = effective(filename, lineno, frame) | |
| if bp: | |
| self.currentbp = bp.number | |
| if (flag and bp.temporary): | |
| self.do_clear(str(bp.number)) | |
| return True | |
| else: | |
| return False | |
| def do_clear(self, arg): | |
| raise NotImplementedError, "subclass of bdb must implement do_clear()" | |
| def break_anywhere(self, frame): | |
| return self.canonic(frame.f_code.co_filename) in self.breaks | |
| # Derived classes should override the user_* methods | |
| # to gain control. | |
| def user_call(self, frame, argument_list): | |
| """This method is called when there is the remote possibility | |
| that we ever need to stop in this function.""" | |
| pass | |
| def user_line(self, frame): | |
| """This method is called when we stop or break at this line.""" | |
| pass | |
| def user_return(self, frame, return_value): | |
| """This method is called when a return trap is set here.""" | |
| pass | |
| def user_exception(self, frame, exc_info): | |
| exc_type, exc_value, exc_traceback = exc_info | |
| """This method is called if an exception occurs, | |
| but only if we are to stop at or just below this level.""" | |
| pass | |
| def _set_stopinfo(self, stopframe, returnframe, stoplineno=0): | |
| self.stopframe = stopframe | |
| self.returnframe = returnframe | |
| self.quitting = 0 | |
| # stoplineno >= 0 means: stop at line >= the stoplineno | |
| # stoplineno -1 means: don't stop at all | |
| self.stoplineno = stoplineno | |
| # Derived classes and clients can call the following methods | |
| # to affect the stepping state. | |
| def set_until(self, frame): #the name "until" is borrowed from gdb | |
| """Stop when the line with the line no greater than the current one is | |
| reached or when returning from current frame""" | |
| self._set_stopinfo(frame, frame, frame.f_lineno+1) | |
| def set_step(self): | |
| """Stop after one line of code.""" | |
| self._set_stopinfo(None, None) | |
| def set_next(self, frame): | |
| """Stop on the next line in or below the given frame.""" | |
| self._set_stopinfo(frame, None) | |
| def set_return(self, frame): | |
| """Stop when returning from the given frame.""" | |
| self._set_stopinfo(frame.f_back, frame) | |
| def set_trace(self, frame=None): | |
| """Start debugging from `frame`. | |
| If frame is not specified, debugging starts from caller's frame. | |
| """ | |
| if frame is None: | |
| frame = sys._getframe().f_back | |
| self.reset() | |
| while frame: | |
| frame.f_trace = self.trace_dispatch | |
| self.botframe = frame | |
| frame = frame.f_back | |
| self.set_step() | |
| sys.settrace(self.trace_dispatch) | |
| def set_continue(self): | |
| # Don't stop except at breakpoints or when finished | |
| self._set_stopinfo(self.botframe, None, -1) | |
| if not self.breaks: | |
| # no breakpoints; run without debugger overhead | |
| sys.settrace(None) | |
| frame = sys._getframe().f_back | |
| while frame and frame is not self.botframe: | |
| del frame.f_trace | |
| frame = frame.f_back | |
| def set_quit(self): | |
| self.stopframe = self.botframe | |
| self.returnframe = None | |
| self.quitting = 1 | |
| sys.settrace(None) | |
| # Derived classes and clients can call the following methods | |
| # to manipulate breakpoints. These methods return an | |
| # error message is something went wrong, None if all is well. | |
| # Set_break prints out the breakpoint line and file:lineno. | |
| # Call self.get_*break*() to see the breakpoints or better | |
| # for bp in Breakpoint.bpbynumber: if bp: bp.bpprint(). | |
| def set_break(self, filename, lineno, temporary=0, cond = None, | |
| funcname=None): | |
| filename = self.canonic(filename) | |
| import linecache # Import as late as possible | |
| line = linecache.getline(filename, lineno) | |
| if not line: | |
| return 'Line %s:%d does not exist' % (filename, | |
| lineno) | |
| if not filename in self.breaks: | |
| self.breaks[filename] = [] | |
| list = self.breaks[filename] | |
| if not lineno in list: | |
| list.append(lineno) | |
| bp = Breakpoint(filename, lineno, temporary, cond, funcname) | |
| def _prune_breaks(self, filename, lineno): | |
| if (filename, lineno) not in Breakpoint.bplist: | |
| self.breaks[filename].remove(lineno) | |
| if not self.breaks[filename]: | |
| del self.breaks[filename] | |
| def clear_break(self, filename, lineno): | |
| filename = self.canonic(filename) | |
| if not filename in self.breaks: | |
| return 'There are no breakpoints in %s' % filename | |
| if lineno not in self.breaks[filename]: | |
| return 'There is no breakpoint at %s:%d' % (filename, | |
| lineno) | |
| # If there's only one bp in the list for that file,line | |
| # pair, then remove the breaks entry | |
| for bp in Breakpoint.bplist[filename, lineno][:]: | |
| bp.deleteMe() | |
| self._prune_breaks(filename, lineno) | |
| def clear_bpbynumber(self, arg): | |
| try: | |
| number = int(arg) | |
| except: | |
| return 'Non-numeric breakpoint number (%s)' % arg | |
| try: | |
| bp = Breakpoint.bpbynumber[number] | |
| except IndexError: | |
| return 'Breakpoint number (%d) out of range' % number | |
| if not bp: | |
| return 'Breakpoint (%d) already deleted' % number | |
| bp.deleteMe() | |
| self._prune_breaks(bp.file, bp.line) | |
| def clear_all_file_breaks(self, filename): | |
| filename = self.canonic(filename) | |
| if not filename in self.breaks: | |
| return 'There are no breakpoints in %s' % filename | |
| for line in self.breaks[filename]: | |
| blist = Breakpoint.bplist[filename, line] | |
| for bp in blist: | |
| bp.deleteMe() | |
| del self.breaks[filename] | |
| def clear_all_breaks(self): | |
| if not self.breaks: | |
| return 'There are no breakpoints' | |
| for bp in Breakpoint.bpbynumber: | |
| if bp: | |
| bp.deleteMe() | |
| self.breaks = {} | |
| def get_break(self, filename, lineno): | |
| filename = self.canonic(filename) | |
| return filename in self.breaks and \ | |
| lineno in self.breaks[filename] | |
| def get_breaks(self, filename, lineno): | |
| filename = self.canonic(filename) | |
| return filename in self.breaks and \ | |
| lineno in self.breaks[filename] and \ | |
| Breakpoint.bplist[filename, lineno] or [] | |
| def get_file_breaks(self, filename): | |
| filename = self.canonic(filename) | |
| if filename in self.breaks: | |
| return self.breaks[filename] | |
| else: | |
| return [] | |
| def get_all_breaks(self): | |
| return self.breaks | |
| # Derived classes and clients can call the following method | |
| # to get a data structure representing a stack trace. | |
| def get_stack(self, f, t): | |
| stack = [] | |
| if t and t.tb_frame is f: | |
| t = t.tb_next | |
| while f is not None: | |
| stack.append((f, f.f_lineno)) | |
| if f is self.botframe: | |
| break | |
| f = f.f_back | |
| stack.reverse() | |
| i = max(0, len(stack) - 1) | |
| while t is not None: | |
| stack.append((t.tb_frame, t.tb_lineno)) | |
| t = t.tb_next | |
| if f is None: | |
| i = max(0, len(stack) - 1) | |
| return stack, i | |
| # | |
| def format_stack_entry(self, frame_lineno, lprefix=': '): | |
| import linecache, repr | |
| frame, lineno = frame_lineno | |
| filename = self.canonic(frame.f_code.co_filename) | |
| s = '%s(%r)' % (filename, lineno) | |
| if frame.f_code.co_name: | |
| s = s + frame.f_code.co_name | |
| else: | |
| s = s + "<lambda>" | |
| if '__args__' in frame.f_locals: | |
| args = frame.f_locals['__args__'] | |
| else: | |
| args = None | |
| if args: | |
| s = s + repr.repr(args) | |
| else: | |
| s = s + '()' | |
| if '__return__' in frame.f_locals: | |
| rv = frame.f_locals['__return__'] | |
| s = s + '->' | |
| s = s + repr.repr(rv) | |
| line = linecache.getline(filename, lineno, frame.f_globals) | |
| if line: s = s + lprefix + line.strip() | |
| return s | |
| # The following two methods can be called by clients to use | |
| # a debugger to debug a statement, given as a string. | |
| def run(self, cmd, globals=None, locals=None): | |
| if globals is None: | |
| import __main__ | |
| globals = __main__.__dict__ | |
| if locals is None: | |
| locals = globals | |
| self.reset() | |
| sys.settrace(self.trace_dispatch) | |
| if not isinstance(cmd, types.CodeType): | |
| cmd = cmd+'\n' | |
| try: | |
| exec cmd in globals, locals | |
| except BdbQuit: | |
| pass | |
| finally: | |
| self.quitting = 1 | |
| sys.settrace(None) | |
| def runeval(self, expr, globals=None, locals=None): | |
| if globals is None: | |
| import __main__ | |
| globals = __main__.__dict__ | |
| if locals is None: | |
| locals = globals | |
| self.reset() | |
| sys.settrace(self.trace_dispatch) | |
| if not isinstance(expr, types.CodeType): | |
| expr = expr+'\n' | |
| try: | |
| return eval(expr, globals, locals) | |
| except BdbQuit: | |
| pass | |
| finally: | |
| self.quitting = 1 | |
| sys.settrace(None) | |
| def runctx(self, cmd, globals, locals): | |
| # B/W compatibility | |
| self.run(cmd, globals, locals) | |
| # This method is more useful to debug a single function call. | |
| def runcall(self, func, *args, **kwds): | |
| self.reset() | |
| sys.settrace(self.trace_dispatch) | |
| res = None | |
| try: | |
| res = func(*args, **kwds) | |
| except BdbQuit: | |
| pass | |
| finally: | |
| self.quitting = 1 | |
| sys.settrace(None) | |
| return res | |
| def set_trace(): | |
| Bdb().set_trace() | |
| class Breakpoint: | |
| """Breakpoint class | |
| Implements temporary breakpoints, ignore counts, disabling and | |
| (re)-enabling, and conditionals. | |
| Breakpoints are indexed by number through bpbynumber and by | |
| the file,line tuple using bplist. The former points to a | |
| single instance of class Breakpoint. The latter points to a | |
| list of such instances since there may be more than one | |
| breakpoint per line. | |
| """ | |
| # XXX Keeping state in the class is a mistake -- this means | |
| # you cannot have more than one active Bdb instance. | |
| next = 1 # Next bp to be assigned | |
| bplist = {} # indexed by (file, lineno) tuple | |
| bpbynumber = [None] # Each entry is None or an instance of Bpt | |
| # index 0 is unused, except for marking an | |
| # effective break .... see effective() | |
| def __init__(self, file, line, temporary=0, cond=None, funcname=None): | |
| self.funcname = funcname | |
| # Needed if funcname is not None. | |
| self.func_first_executable_line = None | |
| self.file = file # This better be in canonical form! | |
| self.line = line | |
| self.temporary = temporary | |
| self.cond = cond | |
| self.enabled = 1 | |
| self.ignore = 0 | |
| self.hits = 0 | |
| self.number = Breakpoint.next | |
| Breakpoint.next = Breakpoint.next + 1 | |
| # Build the two lists | |
| self.bpbynumber.append(self) | |
| if (file, line) in self.bplist: | |
| self.bplist[file, line].append(self) | |
| else: | |
| self.bplist[file, line] = [self] | |
| def deleteMe(self): | |
| index = (self.file, self.line) | |
| self.bpbynumber[self.number] = None # No longer in list | |
| self.bplist[index].remove(self) | |
| if not self.bplist[index]: | |
| # No more bp for this f:l combo | |
| del self.bplist[index] | |
| def enable(self): | |
| self.enabled = 1 | |
| def disable(self): | |
| self.enabled = 0 | |
| def bpprint(self, out=None): | |
| if out is None: | |
| out = sys.stdout | |
| if self.temporary: | |
| disp = 'del ' | |
| else: | |
| disp = 'keep ' | |
| if self.enabled: | |
| disp = disp + 'yes ' | |
| else: | |
| disp = disp + 'no ' | |
| print >>out, '%-4dbreakpoint %s at %s:%d' % (self.number, disp, | |
| self.file, self.line) | |
| if self.cond: | |
| print >>out, '\tstop only if %s' % (self.cond,) | |
| if self.ignore: | |
| print >>out, '\tignore next %d hits' % (self.ignore) | |
| if (self.hits): | |
| if (self.hits > 1): ss = 's' | |
| else: ss = '' | |
| print >>out, ('\tbreakpoint already hit %d time%s' % | |
| (self.hits, ss)) | |
| # -----------end of Breakpoint class---------- | |
| def checkfuncname(b, frame): | |
| """Check whether we should break here because of `b.funcname`.""" | |
| if not b.funcname: | |
| # Breakpoint was set via line number. | |
| if b.line != frame.f_lineno: | |
| # Breakpoint was set at a line with a def statement and the function | |
| # defined is called: don't break. | |
| return False | |
| return True | |
| # Breakpoint set via function name. | |
| if frame.f_code.co_name != b.funcname: | |
| # It's not a function call, but rather execution of def statement. | |
| return False | |
| # We are in the right frame. | |
| if not b.func_first_executable_line: | |
| # The function is entered for the 1st time. | |
| b.func_first_executable_line = frame.f_lineno | |
| if b.func_first_executable_line != frame.f_lineno: | |
| # But we are not at the first line number: don't break. | |
| return False | |
| return True | |
| # Determines if there is an effective (active) breakpoint at this | |
| # line of code. Returns breakpoint number or 0 if none | |
| def effective(file, line, frame): | |
| """Determine which breakpoint for this file:line is to be acted upon. | |
| Called only if we know there is a bpt at this | |
| location. Returns breakpoint that was triggered and a flag | |
| that indicates if it is ok to delete a temporary bp. | |
| """ | |
| possibles = Breakpoint.bplist[file,line] | |
| for i in range(0, len(possibles)): | |
| b = possibles[i] | |
| if b.enabled == 0: | |
| continue | |
| if not checkfuncname(b, frame): | |
| continue | |
| # Count every hit when bp is enabled | |
| b.hits = b.hits + 1 | |
| if not b.cond: | |
| # If unconditional, and ignoring, | |
| # go on to next, else break | |
| if b.ignore > 0: | |
| b.ignore = b.ignore -1 | |
| continue | |
| else: | |
| # breakpoint and marker that's ok | |
| # to delete if temporary | |
| return (b,1) | |
| else: | |
| # Conditional bp. | |
| # Ignore count applies only to those bpt hits where the | |
| # condition evaluates to true. | |
| try: | |
| val = eval(b.cond, frame.f_globals, | |
| frame.f_locals) | |
| if val: | |
| if b.ignore > 0: | |
| b.ignore = b.ignore -1 | |
| # continue | |
| else: | |
| return (b,1) | |
| # else: | |
| # continue | |
| except: | |
| # if eval fails, most conservative | |
| # thing is to stop on breakpoint | |
| # regardless of ignore count. | |
| # Don't delete temporary, | |
| # as another hint to user. | |
| return (b,0) | |
| return (None, None) | |
| # -------------------- testing -------------------- | |
| class Tdb(Bdb): | |
| def user_call(self, frame, args): | |
| name = frame.f_code.co_name | |
| if not name: name = '???' | |
| print '+++ call', name, args | |
| def user_line(self, frame): | |
| import linecache | |
| name = frame.f_code.co_name | |
| if not name: name = '???' | |
| fn = self.canonic(frame.f_code.co_filename) | |
| line = linecache.getline(fn, frame.f_lineno, frame.f_globals) | |
| print '+++', fn, frame.f_lineno, name, ':', line.strip() | |
| def user_return(self, frame, retval): | |
| print '+++ return', retval | |
| def user_exception(self, frame, exc_stuff): | |
| print '+++ exception', exc_stuff | |
| self.set_continue() | |
| def foo(n): | |
| print 'foo(', n, ')' | |
| x = bar(n*10) | |
| print 'bar returned', x | |
| def bar(a): | |
| print 'bar(', a, ')' | |
| return a/2 | |
| def test(): | |
| t = Tdb() | |
| t.run('import bdb; bdb.foo(10)') | |
| # end |