summaryrefslogtreecommitdiffstats
path: root/Lib/bdb.py
blob: 66d3457c6b7a5f6ca17354b41280054512cbde04 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
# A generic Python debugger base class.
# This class takes care of details of the trace facility;
# a derived class should implement user interaction.
# There are two debuggers based upon this:
# 'pdb', a text-oriented debugger not unlike dbx or gdb;
# and 'wdb', a window-oriented debugger.
# And of course... you can roll your own!

import sys

BdbQuit = 'bdb.BdbQuit' # Exception to give up completely


class Bdb: # Basic Debugger
	
	def init(self):
		self.breaks = {}
		return self
	
	def reset(self):
		self.botframe = None
		self.stopframe = None
		self.returnframe = None
		self.quitting = 0
	
	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)
		print 'bdb.Bdb.dispatch: unknown debugging event:', `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):
		frame.f_locals['__args__'] = arg
		if self.botframe is None:
			# First call of dispatch since reset()
			self.botframe = frame
			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
	
	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 stop_here(self, frame):
		if self.stopframe is None:
			return 1
		if frame is self.stopframe:
			return 1
		while frame is not None and frame is not self.stopframe:
			if frame is self.botframe:
				return 1
			frame = frame.f_back
		return 0
	
	def break_here(self, frame):
		if not self.breaks.has_key(frame.f_code.co_filename):
			return 0
		if not frame.f_lineno in \
				self.breaks[frame.f_code.co_filename]:
			return 0
		return 1
	
	def break_anywhere(self, frame):
		return self.breaks.has_key(frame.f_code.co_filename)
	
	# 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_type, exc_value, exc_traceback)):
		# This method is called if an exception occurs,
		# but only if we are to stop at or just below this level
		pass
	
	# Derived classes and clients can call the following methods
	# to affect the stepping state.
	
	def set_step(self):
		# Stop after one line of code
		self.stopframe = None
		self.returnframe = None
		self.quitting = 0
	
	def set_next(self, frame):
		# Stop on the next line in or below the given frame
		self.stopframe = frame
		self.returnframe = None
		self.quitting = 0
	
	def set_return(self, frame):
		# Stop when returning from the given frame
		self.stopframe = frame.f_back
		self.returnframe = frame
		self.quitting = 0
	
	def set_continue(self):
		# Don't stop except at breakpoints or when finished
		self.stopframe = self.botframe
		self.returnframe = None
		self.quitting = 0
	
	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.
	# Call self.get_*break*() to see the breakpoints.
	
	def set_break(self, filename, lineno):
		import linecache # Import as late as possible
		line = linecache.getline(filename, lineno)
		if not line:
			return 'That line does not exist!'
		if not self.breaks.has_key(filename):
			self.breaks[filename] = []
		list = self.breaks[filename]
		if lineno in list:
			return 'There is already a breakpoint there!'
		list.append(lineno)
	
	def clear_break(self, filename, lineno):
		if not self.breaks.has_key(filename):
			return 'There are no breakpoints in that file!'
		if lineno not in self.breaks[filename]:
			return 'There is no breakpoint there!'
		self.breaks[filename].remove(lineno)
		if not self.breaks[filename]:
			del self.breaks[filename]
	
	def clear_all_file_breaks(self, filename):
		if not self.breaks.has_key(filename):
			return 'There are no breakpoints in that file!'
		del self.breaks[filename]
	
	def clear_all_breaks(self, filename, lineno):
		if not self.breaks:
			return 'There are no breakpoints!'
		self.breaks = {}
	
	def get_break(self, filename, lineno):
		return self.breaks.has_key(filename) and \
			lineno in self.breaks[filename]
	
	def get_file_breaks(self, filename):
		if self.breaks.has_key(filename):
			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
		return stack, i
	
	# 
	
	def format_stack_entry(self, frame_lineno):
		import codehack, linecache, repr, string
		frame, lineno = frame_lineno
		filename = frame.f_code.co_filename
		s = filename + '(' + `lineno` + ')'
		s = s + codehack.getcodename(frame.f_code)
		if frame.f_locals.has_key('__args__'):
			args = frame.f_locals['__args__']
			if args is not None:
				s = s + repr.repr(args)
		if frame.f_locals.has_key('__return__'):
			rv = frame.f_locals['__return__']
			s = s + '->'
			s = s + repr.repr(rv)
		line = linecache.getline(filename, lineno)
		if line: s = s + ': ' + string.strip(line)
		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):
		import __main__
		dict = __main__.__dict__
		self.runctx(cmd, dict, dict)
	
	def runctx(self, cmd, globals, locals):
		self.reset()
		sys.settrace(self.trace_dispatch)
		try:
			try:
				exec(cmd + '\n', globals, locals)
			except BdbQuit:
				pass
		finally:
			self.quitting = 1
			sys.settrace(None)

	# This method is more useful to debug a single function call.

	def runcall(self, func, *args):
		self.reset()
		sys.settrace(self.trace_dispatch)
		try:
			try:
				apply(func, args)
			except BdbQuit:
				pass
		finally:
			self.quitting = 1
			sys.settrace(None)


# -------------------- testing --------------------

class Tdb(Bdb):
	def user_call(self, frame, args):
		import codehack
		name = codehack.getcodename(frame.f_code)
		if not name: name = '???'
		print '+++ call', name, args
	def user_line(self, frame):
		import linecache, string, codehack
		name = codehack.getcodename(frame.f_code)
		if not name: name = '???'
		fn = frame.f_code.co_filename
		line = linecache.getline(fn, frame.f_lineno)
		print '+++', fn, frame.f_lineno, name, ':', string.strip(line)
	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():
	import linecache
	linecache.checkcache()
	t = Tdb().init()
	t.run('import bdb; bdb.foo(10)')