1# Verify that gdb can pretty-print the various PyObject* types 2# 3# The code for testing gdb was adapted from similar work in Unladen Swallow's 4# Lib/test/test_jit_gdb.py 5 6import os 7import platform 8import re 9import subprocess 10import sys 11import sysconfig 12import textwrap 13import unittest 14 15from test import support 16from test.support import run_unittest, findfile, python_is_optimized 17 18def get_gdb_version(): 19 try: 20 cmd = ["gdb", "-nx", "--version"] 21 proc = subprocess.Popen(cmd, 22 stdout=subprocess.PIPE, 23 stderr=subprocess.PIPE, 24 universal_newlines=True) 25 with proc: 26 version, stderr = proc.communicate() 27 28 if proc.returncode: 29 raise Exception(f"Command {' '.join(cmd)!r} failed " 30 f"with exit code {proc.returncode}: " 31 f"stdout={version!r} stderr={stderr!r}") 32 except OSError: 33 # This is what "no gdb" looks like. There may, however, be other 34 # errors that manifest this way too. 35 raise unittest.SkipTest("Couldn't find gdb on the path") 36 37 # Regex to parse: 38 # 'GNU gdb (GDB; SUSE Linux Enterprise 12) 7.7\n' -> 7.7 39 # 'GNU gdb (GDB) Fedora 7.9.1-17.fc22\n' -> 7.9 40 # 'GNU gdb 6.1.1 [FreeBSD]\n' -> 6.1 41 # 'GNU gdb (GDB) Fedora (7.5.1-37.fc18)\n' -> 7.5 42 # 'HP gdb 6.7 for HP Itanium (32 or 64 bit) and target HP-UX 11iv2 and 11iv3.\n' -> 6.7 43 match = re.search(r"^(?:GNU|HP) gdb.*?\b(\d+)\.(\d+)", version) 44 if match is None: 45 raise Exception("unable to parse GDB version: %r" % version) 46 return (version, int(match.group(1)), int(match.group(2))) 47 48gdb_version, gdb_major_version, gdb_minor_version = get_gdb_version() 49if gdb_major_version < 7: 50 raise unittest.SkipTest("gdb versions before 7.0 didn't support python " 51 "embedding. Saw %s.%s:\n%s" 52 % (gdb_major_version, gdb_minor_version, 53 gdb_version)) 54 55if not sysconfig.is_python_build(): 56 raise unittest.SkipTest("test_gdb only works on source builds at the moment.") 57 58if 'Clang' in platform.python_compiler() and sys.platform == 'darwin': 59 raise unittest.SkipTest("test_gdb doesn't work correctly when python is" 60 " built with LLVM clang") 61 62if ((sysconfig.get_config_var('PGO_PROF_USE_FLAG') or 'xxx') in 63 (sysconfig.get_config_var('PY_CORE_CFLAGS') or '')): 64 raise unittest.SkipTest("test_gdb is not reliable on PGO builds") 65 66# Location of custom hooks file in a repository checkout. 67checkout_hook_path = os.path.join(os.path.dirname(sys.executable), 68 'python-gdb.py') 69 70PYTHONHASHSEED = '123' 71 72 73def cet_protection(): 74 cflags = sysconfig.get_config_var('CFLAGS') 75 if not cflags: 76 return False 77 flags = cflags.split() 78 # True if "-mcet -fcf-protection" options are found, but false 79 # if "-fcf-protection=none" or "-fcf-protection=return" is found. 80 return (('-mcet' in flags) 81 and any((flag.startswith('-fcf-protection') 82 and not flag.endswith(("=none", "=return"))) 83 for flag in flags)) 84 85# Control-flow enforcement technology 86CET_PROTECTION = cet_protection() 87 88 89def run_gdb(*args, **env_vars): 90 """Runs gdb in --batch mode with the additional arguments given by *args. 91 92 Returns its (stdout, stderr) decoded from utf-8 using the replace handler. 93 """ 94 if env_vars: 95 env = os.environ.copy() 96 env.update(env_vars) 97 else: 98 env = None 99 # -nx: Do not execute commands from any .gdbinit initialization files 100 # (issue #22188) 101 base_cmd = ('gdb', '--batch', '-nx') 102 if (gdb_major_version, gdb_minor_version) >= (7, 4): 103 base_cmd += ('-iex', 'add-auto-load-safe-path ' + checkout_hook_path) 104 proc = subprocess.Popen(base_cmd + args, 105 # Redirect stdin to prevent GDB from messing with 106 # the terminal settings 107 stdin=subprocess.PIPE, 108 stdout=subprocess.PIPE, 109 stderr=subprocess.PIPE, 110 env=env) 111 with proc: 112 out, err = proc.communicate() 113 return out.decode('utf-8', 'replace'), err.decode('utf-8', 'replace') 114 115# Verify that "gdb" was built with the embedded python support enabled: 116gdbpy_version, _ = run_gdb("--eval-command=python import sys; print(sys.version_info)") 117if not gdbpy_version: 118 raise unittest.SkipTest("gdb not built with embedded python support") 119 120# Verify that "gdb" can load our custom hooks, as OS security settings may 121# disallow this without a customized .gdbinit. 122_, gdbpy_errors = run_gdb('--args', sys.executable) 123if "auto-loading has been declined" in gdbpy_errors: 124 msg = "gdb security settings prevent use of custom hooks: " 125 raise unittest.SkipTest(msg + gdbpy_errors.rstrip()) 126 127def gdb_has_frame_select(): 128 # Does this build of gdb have gdb.Frame.select ? 129 stdout, _ = run_gdb("--eval-command=python print(dir(gdb.Frame))") 130 m = re.match(r'.*\[(.*)\].*', stdout) 131 if not m: 132 raise unittest.SkipTest("Unable to parse output from gdb.Frame.select test") 133 gdb_frame_dir = m.group(1).split(', ') 134 return "'select'" in gdb_frame_dir 135 136HAS_PYUP_PYDOWN = gdb_has_frame_select() 137 138BREAKPOINT_FN='builtin_id' 139 140@unittest.skipIf(support.PGO, "not useful for PGO") 141class DebuggerTests(unittest.TestCase): 142 143 """Test that the debugger can debug Python.""" 144 145 def get_stack_trace(self, source=None, script=None, 146 breakpoint=BREAKPOINT_FN, 147 cmds_after_breakpoint=None, 148 import_site=False): 149 ''' 150 Run 'python -c SOURCE' under gdb with a breakpoint. 151 152 Support injecting commands after the breakpoint is reached 153 154 Returns the stdout from gdb 155 156 cmds_after_breakpoint: if provided, a list of strings: gdb commands 157 ''' 158 # We use "set breakpoint pending yes" to avoid blocking with a: 159 # Function "foo" not defined. 160 # Make breakpoint pending on future shared library load? (y or [n]) 161 # error, which typically happens python is dynamically linked (the 162 # breakpoints of interest are to be found in the shared library) 163 # When this happens, we still get: 164 # Function "textiowrapper_write" not defined. 165 # emitted to stderr each time, alas. 166 167 # Initially I had "--eval-command=continue" here, but removed it to 168 # avoid repeated print breakpoints when traversing hierarchical data 169 # structures 170 171 # Generate a list of commands in gdb's language: 172 commands = ['set breakpoint pending yes', 173 'break %s' % breakpoint, 174 175 # The tests assume that the first frame of printed 176 # backtrace will not contain program counter, 177 # that is however not guaranteed by gdb 178 # therefore we need to use 'set print address off' to 179 # make sure the counter is not there. For example: 180 # #0 in PyObject_Print ... 181 # is assumed, but sometimes this can be e.g. 182 # #0 0x00003fffb7dd1798 in PyObject_Print ... 183 'set print address off', 184 185 'run'] 186 187 # GDB as of 7.4 onwards can distinguish between the 188 # value of a variable at entry vs current value: 189 # http://sourceware.org/gdb/onlinedocs/gdb/Variables.html 190 # which leads to the selftests failing with errors like this: 191 # AssertionError: 'v@entry=()' != '()' 192 # Disable this: 193 if (gdb_major_version, gdb_minor_version) >= (7, 4): 194 commands += ['set print entry-values no'] 195 196 if cmds_after_breakpoint: 197 if CET_PROTECTION: 198 # bpo-32962: When Python is compiled with -mcet 199 # -fcf-protection, function arguments are unusable before 200 # running the first instruction of the function entry point. 201 # The 'next' command makes the required first step. 202 commands += ['next'] 203 commands += cmds_after_breakpoint 204 else: 205 commands += ['backtrace'] 206 207 # print commands 208 209 # Use "commands" to generate the arguments with which to invoke "gdb": 210 args = ['--eval-command=%s' % cmd for cmd in commands] 211 args += ["--args", 212 sys.executable] 213 args.extend(subprocess._args_from_interpreter_flags()) 214 215 if not import_site: 216 # -S suppresses the default 'import site' 217 args += ["-S"] 218 219 if source: 220 args += ["-c", source] 221 elif script: 222 args += [script] 223 224 # Use "args" to invoke gdb, capturing stdout, stderr: 225 out, err = run_gdb(*args, PYTHONHASHSEED=PYTHONHASHSEED) 226 227 for line in err.splitlines(): 228 print(line, file=sys.stderr) 229 230 # bpo-34007: Sometimes some versions of the shared libraries that 231 # are part of the traceback are compiled in optimised mode and the 232 # Program Counter (PC) is not present, not allowing gdb to walk the 233 # frames back. When this happens, the Python bindings of gdb raise 234 # an exception, making the test impossible to succeed. 235 if "PC not saved" in err: 236 raise unittest.SkipTest("gdb cannot walk the frame object" 237 " because the Program Counter is" 238 " not present") 239 240 # bpo-40019: Skip the test if gdb failed to read debug information 241 # because the Python binary is optimized. 242 for pattern in ( 243 '(frame information optimized out)', 244 'Unable to read information on python frame', 245 ): 246 if pattern in out: 247 raise unittest.SkipTest(f"{pattern!r} found in gdb output") 248 249 return out 250 251 def get_gdb_repr(self, source, 252 cmds_after_breakpoint=None, 253 import_site=False): 254 # Given an input python source representation of data, 255 # run "python -c'id(DATA)'" under gdb with a breakpoint on 256 # builtin_id and scrape out gdb's representation of the "op" 257 # parameter, and verify that the gdb displays the same string 258 # 259 # Verify that the gdb displays the expected string 260 # 261 # For a nested structure, the first time we hit the breakpoint will 262 # give us the top-level structure 263 264 # NOTE: avoid decoding too much of the traceback as some 265 # undecodable characters may lurk there in optimized mode 266 # (issue #19743). 267 cmds_after_breakpoint = cmds_after_breakpoint or ["backtrace 1"] 268 gdb_output = self.get_stack_trace(source, breakpoint=BREAKPOINT_FN, 269 cmds_after_breakpoint=cmds_after_breakpoint, 270 import_site=import_site) 271 # gdb can insert additional '\n' and space characters in various places 272 # in its output, depending on the width of the terminal it's connected 273 # to (using its "wrap_here" function) 274 m = re.search( 275 # Match '#0 builtin_id(self=..., v=...)' 276 r'#0\s+builtin_id\s+\(self\=.*,\s+v=\s*(.*?)?\)' 277 # Match ' at Python/bltinmodule.c'. 278 # bpo-38239: builtin_id() is defined in Python/bltinmodule.c, 279 # but accept any "Directory\file.c" to support Link Time 280 # Optimization (LTO). 281 r'\s+at\s+\S*[A-Za-z]+/[A-Za-z0-9_-]+\.c', 282 gdb_output, re.DOTALL) 283 if not m: 284 self.fail('Unexpected gdb output: %r\n%s' % (gdb_output, gdb_output)) 285 return m.group(1), gdb_output 286 287 def assertEndsWith(self, actual, exp_end): 288 '''Ensure that the given "actual" string ends with "exp_end"''' 289 self.assertTrue(actual.endswith(exp_end), 290 msg='%r did not end with %r' % (actual, exp_end)) 291 292 def assertMultilineMatches(self, actual, pattern): 293 m = re.match(pattern, actual, re.DOTALL) 294 if not m: 295 self.fail(msg='%r did not match %r' % (actual, pattern)) 296 297 def get_sample_script(self): 298 return findfile('gdb_sample.py') 299 300class PrettyPrintTests(DebuggerTests): 301 def test_getting_backtrace(self): 302 gdb_output = self.get_stack_trace('id(42)') 303 self.assertTrue(BREAKPOINT_FN in gdb_output) 304 305 def assertGdbRepr(self, val, exp_repr=None): 306 # Ensure that gdb's rendering of the value in a debugged process 307 # matches repr(value) in this process: 308 gdb_repr, gdb_output = self.get_gdb_repr('id(' + ascii(val) + ')') 309 if not exp_repr: 310 exp_repr = repr(val) 311 self.assertEqual(gdb_repr, exp_repr, 312 ('%r did not equal expected %r; full output was:\n%s' 313 % (gdb_repr, exp_repr, gdb_output))) 314 315 def test_int(self): 316 'Verify the pretty-printing of various int values' 317 self.assertGdbRepr(42) 318 self.assertGdbRepr(0) 319 self.assertGdbRepr(-7) 320 self.assertGdbRepr(1000000000000) 321 self.assertGdbRepr(-1000000000000000) 322 323 def test_singletons(self): 324 'Verify the pretty-printing of True, False and None' 325 self.assertGdbRepr(True) 326 self.assertGdbRepr(False) 327 self.assertGdbRepr(None) 328 329 def test_dicts(self): 330 'Verify the pretty-printing of dictionaries' 331 self.assertGdbRepr({}) 332 self.assertGdbRepr({'foo': 'bar'}, "{'foo': 'bar'}") 333 # Python preserves insertion order since 3.6 334 self.assertGdbRepr({'foo': 'bar', 'douglas': 42}, "{'foo': 'bar', 'douglas': 42}") 335 336 def test_lists(self): 337 'Verify the pretty-printing of lists' 338 self.assertGdbRepr([]) 339 self.assertGdbRepr(list(range(5))) 340 341 def test_bytes(self): 342 'Verify the pretty-printing of bytes' 343 self.assertGdbRepr(b'') 344 self.assertGdbRepr(b'And now for something hopefully the same') 345 self.assertGdbRepr(b'string with embedded NUL here \0 and then some more text') 346 self.assertGdbRepr(b'this is a tab:\t' 347 b' this is a slash-N:\n' 348 b' this is a slash-R:\r' 349 ) 350 351 self.assertGdbRepr(b'this is byte 255:\xff and byte 128:\x80') 352 353 self.assertGdbRepr(bytes([b for b in range(255)])) 354 355 def test_strings(self): 356 'Verify the pretty-printing of unicode strings' 357 # We cannot simply call locale.getpreferredencoding() here, 358 # as GDB might have been linked against a different version 359 # of Python with a different encoding and coercion policy 360 # with respect to PEP 538 and PEP 540. 361 out, err = run_gdb( 362 '--eval-command', 363 'python import locale; print(locale.getpreferredencoding())') 364 365 encoding = out.rstrip() 366 if err or not encoding: 367 raise RuntimeError( 368 f'unable to determine the preferred encoding ' 369 f'of embedded Python in GDB: {err}') 370 371 def check_repr(text): 372 try: 373 text.encode(encoding) 374 printable = True 375 except UnicodeEncodeError: 376 self.assertGdbRepr(text, ascii(text)) 377 else: 378 self.assertGdbRepr(text) 379 380 self.assertGdbRepr('') 381 self.assertGdbRepr('And now for something hopefully the same') 382 self.assertGdbRepr('string with embedded NUL here \0 and then some more text') 383 384 # Test printing a single character: 385 # U+2620 SKULL AND CROSSBONES 386 check_repr('\u2620') 387 388 # Test printing a Japanese unicode string 389 # (I believe this reads "mojibake", using 3 characters from the CJK 390 # Unified Ideographs area, followed by U+3051 HIRAGANA LETTER KE) 391 check_repr('\u6587\u5b57\u5316\u3051') 392 393 # Test a character outside the BMP: 394 # U+1D121 MUSICAL SYMBOL C CLEF 395 # This is: 396 # UTF-8: 0xF0 0x9D 0x84 0xA1 397 # UTF-16: 0xD834 0xDD21 398 check_repr(chr(0x1D121)) 399 400 def test_tuples(self): 401 'Verify the pretty-printing of tuples' 402 self.assertGdbRepr(tuple(), '()') 403 self.assertGdbRepr((1,), '(1,)') 404 self.assertGdbRepr(('foo', 'bar', 'baz')) 405 406 def test_sets(self): 407 'Verify the pretty-printing of sets' 408 if (gdb_major_version, gdb_minor_version) < (7, 3): 409 self.skipTest("pretty-printing of sets needs gdb 7.3 or later") 410 self.assertGdbRepr(set(), "set()") 411 self.assertGdbRepr(set(['a']), "{'a'}") 412 # PYTHONHASHSEED is need to get the exact frozenset item order 413 if not sys.flags.ignore_environment: 414 self.assertGdbRepr(set(['a', 'b']), "{'a', 'b'}") 415 self.assertGdbRepr(set([4, 5, 6]), "{4, 5, 6}") 416 417 # Ensure that we handle sets containing the "dummy" key value, 418 # which happens on deletion: 419 gdb_repr, gdb_output = self.get_gdb_repr('''s = set(['a','b']) 420s.remove('a') 421id(s)''') 422 self.assertEqual(gdb_repr, "{'b'}") 423 424 def test_frozensets(self): 425 'Verify the pretty-printing of frozensets' 426 if (gdb_major_version, gdb_minor_version) < (7, 3): 427 self.skipTest("pretty-printing of frozensets needs gdb 7.3 or later") 428 self.assertGdbRepr(frozenset(), "frozenset()") 429 self.assertGdbRepr(frozenset(['a']), "frozenset({'a'})") 430 # PYTHONHASHSEED is need to get the exact frozenset item order 431 if not sys.flags.ignore_environment: 432 self.assertGdbRepr(frozenset(['a', 'b']), "frozenset({'a', 'b'})") 433 self.assertGdbRepr(frozenset([4, 5, 6]), "frozenset({4, 5, 6})") 434 435 def test_exceptions(self): 436 # Test a RuntimeError 437 gdb_repr, gdb_output = self.get_gdb_repr(''' 438try: 439 raise RuntimeError("I am an error") 440except RuntimeError as e: 441 id(e) 442''') 443 self.assertEqual(gdb_repr, 444 "RuntimeError('I am an error',)") 445 446 447 # Test division by zero: 448 gdb_repr, gdb_output = self.get_gdb_repr(''' 449try: 450 a = 1 / 0 451except ZeroDivisionError as e: 452 id(e) 453''') 454 self.assertEqual(gdb_repr, 455 "ZeroDivisionError('division by zero',)") 456 457 def test_modern_class(self): 458 'Verify the pretty-printing of new-style class instances' 459 gdb_repr, gdb_output = self.get_gdb_repr(''' 460class Foo: 461 pass 462foo = Foo() 463foo.an_int = 42 464id(foo)''') 465 m = re.match(r'<Foo\(an_int=42\) at remote 0x-?[0-9a-f]+>', gdb_repr) 466 self.assertTrue(m, 467 msg='Unexpected new-style class rendering %r' % gdb_repr) 468 469 def test_subclassing_list(self): 470 'Verify the pretty-printing of an instance of a list subclass' 471 gdb_repr, gdb_output = self.get_gdb_repr(''' 472class Foo(list): 473 pass 474foo = Foo() 475foo += [1, 2, 3] 476foo.an_int = 42 477id(foo)''') 478 m = re.match(r'<Foo\(an_int=42\) at remote 0x-?[0-9a-f]+>', gdb_repr) 479 480 self.assertTrue(m, 481 msg='Unexpected new-style class rendering %r' % gdb_repr) 482 483 def test_subclassing_tuple(self): 484 'Verify the pretty-printing of an instance of a tuple subclass' 485 # This should exercise the negative tp_dictoffset code in the 486 # new-style class support 487 gdb_repr, gdb_output = self.get_gdb_repr(''' 488class Foo(tuple): 489 pass 490foo = Foo((1, 2, 3)) 491foo.an_int = 42 492id(foo)''') 493 m = re.match(r'<Foo\(an_int=42\) at remote 0x-?[0-9a-f]+>', gdb_repr) 494 495 self.assertTrue(m, 496 msg='Unexpected new-style class rendering %r' % gdb_repr) 497 498 def assertSane(self, source, corruption, exprepr=None): 499 '''Run Python under gdb, corrupting variables in the inferior process 500 immediately before taking a backtrace. 501 502 Verify that the variable's representation is the expected failsafe 503 representation''' 504 if corruption: 505 cmds_after_breakpoint=[corruption, 'backtrace'] 506 else: 507 cmds_after_breakpoint=['backtrace'] 508 509 gdb_repr, gdb_output = \ 510 self.get_gdb_repr(source, 511 cmds_after_breakpoint=cmds_after_breakpoint) 512 if exprepr: 513 if gdb_repr == exprepr: 514 # gdb managed to print the value in spite of the corruption; 515 # this is good (see http://bugs.python.org/issue8330) 516 return 517 518 # Match anything for the type name; 0xDEADBEEF could point to 519 # something arbitrary (see http://bugs.python.org/issue8330) 520 pattern = '<.* at remote 0x-?[0-9a-f]+>' 521 522 m = re.match(pattern, gdb_repr) 523 if not m: 524 self.fail('Unexpected gdb representation: %r\n%s' % \ 525 (gdb_repr, gdb_output)) 526 527 def test_NULL_ptr(self): 528 'Ensure that a NULL PyObject* is handled gracefully' 529 gdb_repr, gdb_output = ( 530 self.get_gdb_repr('id(42)', 531 cmds_after_breakpoint=['set variable v=0', 532 'backtrace']) 533 ) 534 535 self.assertEqual(gdb_repr, '0x0') 536 537 def test_NULL_ob_type(self): 538 'Ensure that a PyObject* with NULL ob_type is handled gracefully' 539 self.assertSane('id(42)', 540 'set v->ob_type=0') 541 542 def test_corrupt_ob_type(self): 543 'Ensure that a PyObject* with a corrupt ob_type is handled gracefully' 544 self.assertSane('id(42)', 545 'set v->ob_type=0xDEADBEEF', 546 exprepr='42') 547 548 def test_corrupt_tp_flags(self): 549 'Ensure that a PyObject* with a type with corrupt tp_flags is handled' 550 self.assertSane('id(42)', 551 'set v->ob_type->tp_flags=0x0', 552 exprepr='42') 553 554 def test_corrupt_tp_name(self): 555 'Ensure that a PyObject* with a type with corrupt tp_name is handled' 556 self.assertSane('id(42)', 557 'set v->ob_type->tp_name=0xDEADBEEF', 558 exprepr='42') 559 560 def test_builtins_help(self): 561 'Ensure that the new-style class _Helper in site.py can be handled' 562 563 if sys.flags.no_site: 564 self.skipTest("need site module, but -S option was used") 565 566 # (this was the issue causing tracebacks in 567 # http://bugs.python.org/issue8032#msg100537 ) 568 gdb_repr, gdb_output = self.get_gdb_repr('id(__builtins__.help)', import_site=True) 569 570 m = re.match(r'<_Helper at remote 0x-?[0-9a-f]+>', gdb_repr) 571 self.assertTrue(m, 572 msg='Unexpected rendering %r' % gdb_repr) 573 574 def test_selfreferential_list(self): 575 '''Ensure that a reference loop involving a list doesn't lead proxyval 576 into an infinite loop:''' 577 gdb_repr, gdb_output = \ 578 self.get_gdb_repr("a = [3, 4, 5] ; a.append(a) ; id(a)") 579 self.assertEqual(gdb_repr, '[3, 4, 5, [...]]') 580 581 gdb_repr, gdb_output = \ 582 self.get_gdb_repr("a = [3, 4, 5] ; b = [a] ; a.append(b) ; id(a)") 583 self.assertEqual(gdb_repr, '[3, 4, 5, [[...]]]') 584 585 def test_selfreferential_dict(self): 586 '''Ensure that a reference loop involving a dict doesn't lead proxyval 587 into an infinite loop:''' 588 gdb_repr, gdb_output = \ 589 self.get_gdb_repr("a = {} ; b = {'bar':a} ; a['foo'] = b ; id(a)") 590 591 self.assertEqual(gdb_repr, "{'foo': {'bar': {...}}}") 592 593 def test_selfreferential_old_style_instance(self): 594 gdb_repr, gdb_output = \ 595 self.get_gdb_repr(''' 596class Foo: 597 pass 598foo = Foo() 599foo.an_attr = foo 600id(foo)''') 601 self.assertTrue(re.match(r'<Foo\(an_attr=<\.\.\.>\) at remote 0x-?[0-9a-f]+>', 602 gdb_repr), 603 'Unexpected gdb representation: %r\n%s' % \ 604 (gdb_repr, gdb_output)) 605 606 def test_selfreferential_new_style_instance(self): 607 gdb_repr, gdb_output = \ 608 self.get_gdb_repr(''' 609class Foo(object): 610 pass 611foo = Foo() 612foo.an_attr = foo 613id(foo)''') 614 self.assertTrue(re.match(r'<Foo\(an_attr=<\.\.\.>\) at remote 0x-?[0-9a-f]+>', 615 gdb_repr), 616 'Unexpected gdb representation: %r\n%s' % \ 617 (gdb_repr, gdb_output)) 618 619 gdb_repr, gdb_output = \ 620 self.get_gdb_repr(''' 621class Foo(object): 622 pass 623a = Foo() 624b = Foo() 625a.an_attr = b 626b.an_attr = a 627id(a)''') 628 self.assertTrue(re.match(r'<Foo\(an_attr=<Foo\(an_attr=<\.\.\.>\) at remote 0x-?[0-9a-f]+>\) at remote 0x-?[0-9a-f]+>', 629 gdb_repr), 630 'Unexpected gdb representation: %r\n%s' % \ 631 (gdb_repr, gdb_output)) 632 633 def test_truncation(self): 634 'Verify that very long output is truncated' 635 gdb_repr, gdb_output = self.get_gdb_repr('id(list(range(1000)))') 636 self.assertEqual(gdb_repr, 637 "[0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, " 638 "14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, " 639 "27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, " 640 "40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, " 641 "53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65, " 642 "66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, " 643 "79, 80, 81, 82, 83, 84, 85, 86, 87, 88, 89, 90, 91, " 644 "92, 93, 94, 95, 96, 97, 98, 99, 100, 101, 102, 103, " 645 "104, 105, 106, 107, 108, 109, 110, 111, 112, 113, " 646 "114, 115, 116, 117, 118, 119, 120, 121, 122, 123, " 647 "124, 125, 126, 127, 128, 129, 130, 131, 132, 133, " 648 "134, 135, 136, 137, 138, 139, 140, 141, 142, 143, " 649 "144, 145, 146, 147, 148, 149, 150, 151, 152, 153, " 650 "154, 155, 156, 157, 158, 159, 160, 161, 162, 163, " 651 "164, 165, 166, 167, 168, 169, 170, 171, 172, 173, " 652 "174, 175, 176, 177, 178, 179, 180, 181, 182, 183, " 653 "184, 185, 186, 187, 188, 189, 190, 191, 192, 193, " 654 "194, 195, 196, 197, 198, 199, 200, 201, 202, 203, " 655 "204, 205, 206, 207, 208, 209, 210, 211, 212, 213, " 656 "214, 215, 216, 217, 218, 219, 220, 221, 222, 223, " 657 "224, 225, 226...(truncated)") 658 self.assertEqual(len(gdb_repr), 659 1024 + len('...(truncated)')) 660 661 def test_builtin_method(self): 662 gdb_repr, gdb_output = self.get_gdb_repr('import sys; id(sys.stdout.readlines)') 663 self.assertTrue(re.match(r'<built-in method readlines of _io.TextIOWrapper object at remote 0x-?[0-9a-f]+>', 664 gdb_repr), 665 'Unexpected gdb representation: %r\n%s' % \ 666 (gdb_repr, gdb_output)) 667 668 def test_frames(self): 669 gdb_output = self.get_stack_trace(''' 670def foo(a, b, c): 671 pass 672 673foo(3, 4, 5) 674id(foo.__code__)''', 675 breakpoint='builtin_id', 676 cmds_after_breakpoint=['print (PyFrameObject*)(((PyCodeObject*)v)->co_zombieframe)'] 677 ) 678 self.assertTrue(re.match(r'.*\s+\$1 =\s+Frame 0x-?[0-9a-f]+, for file <string>, line 3, in foo \(\)\s+.*', 679 gdb_output, 680 re.DOTALL), 681 'Unexpected gdb representation: %r\n%s' % (gdb_output, gdb_output)) 682 683@unittest.skipIf(python_is_optimized(), 684 "Python was compiled with optimizations") 685class PyListTests(DebuggerTests): 686 def assertListing(self, expected, actual): 687 self.assertEndsWith(actual, expected) 688 689 def test_basic_command(self): 690 'Verify that the "py-list" command works' 691 bt = self.get_stack_trace(script=self.get_sample_script(), 692 cmds_after_breakpoint=['py-list']) 693 694 self.assertListing(' 5 \n' 695 ' 6 def bar(a, b, c):\n' 696 ' 7 baz(a, b, c)\n' 697 ' 8 \n' 698 ' 9 def baz(*args):\n' 699 ' >10 id(42)\n' 700 ' 11 \n' 701 ' 12 foo(1, 2, 3)\n', 702 bt) 703 704 def test_one_abs_arg(self): 705 'Verify the "py-list" command with one absolute argument' 706 bt = self.get_stack_trace(script=self.get_sample_script(), 707 cmds_after_breakpoint=['py-list 9']) 708 709 self.assertListing(' 9 def baz(*args):\n' 710 ' >10 id(42)\n' 711 ' 11 \n' 712 ' 12 foo(1, 2, 3)\n', 713 bt) 714 715 def test_two_abs_args(self): 716 'Verify the "py-list" command with two absolute arguments' 717 bt = self.get_stack_trace(script=self.get_sample_script(), 718 cmds_after_breakpoint=['py-list 1,3']) 719 720 self.assertListing(' 1 # Sample script for use by test_gdb.py\n' 721 ' 2 \n' 722 ' 3 def foo(a, b, c):\n', 723 bt) 724 725class StackNavigationTests(DebuggerTests): 726 @unittest.skipUnless(HAS_PYUP_PYDOWN, "test requires py-up/py-down commands") 727 @unittest.skipIf(python_is_optimized(), 728 "Python was compiled with optimizations") 729 def test_pyup_command(self): 730 'Verify that the "py-up" command works' 731 bt = self.get_stack_trace(script=self.get_sample_script(), 732 cmds_after_breakpoint=['py-up', 'py-up']) 733 self.assertMultilineMatches(bt, 734 r'''^.* 735#[0-9]+ Frame 0x-?[0-9a-f]+, for file .*gdb_sample.py, line 7, in bar \(a=1, b=2, c=3\) 736 baz\(a, b, c\) 737$''') 738 739 @unittest.skipUnless(HAS_PYUP_PYDOWN, "test requires py-up/py-down commands") 740 def test_down_at_bottom(self): 741 'Verify handling of "py-down" at the bottom of the stack' 742 bt = self.get_stack_trace(script=self.get_sample_script(), 743 cmds_after_breakpoint=['py-down']) 744 self.assertEndsWith(bt, 745 'Unable to find a newer python frame\n') 746 747 @unittest.skipUnless(HAS_PYUP_PYDOWN, "test requires py-up/py-down commands") 748 def test_up_at_top(self): 749 'Verify handling of "py-up" at the top of the stack' 750 bt = self.get_stack_trace(script=self.get_sample_script(), 751 cmds_after_breakpoint=['py-up'] * 5) 752 self.assertEndsWith(bt, 753 'Unable to find an older python frame\n') 754 755 @unittest.skipUnless(HAS_PYUP_PYDOWN, "test requires py-up/py-down commands") 756 @unittest.skipIf(python_is_optimized(), 757 "Python was compiled with optimizations") 758 def test_up_then_down(self): 759 'Verify "py-up" followed by "py-down"' 760 bt = self.get_stack_trace(script=self.get_sample_script(), 761 cmds_after_breakpoint=['py-up', 'py-up', 'py-down']) 762 self.assertMultilineMatches(bt, 763 r'''^.* 764#[0-9]+ Frame 0x-?[0-9a-f]+, for file .*gdb_sample.py, line 7, in bar \(a=1, b=2, c=3\) 765 baz\(a, b, c\) 766#[0-9]+ Frame 0x-?[0-9a-f]+, for file .*gdb_sample.py, line 10, in baz \(args=\(1, 2, 3\)\) 767 id\(42\) 768$''') 769 770class PyBtTests(DebuggerTests): 771 @unittest.skipIf(python_is_optimized(), 772 "Python was compiled with optimizations") 773 def test_bt(self): 774 'Verify that the "py-bt" command works' 775 bt = self.get_stack_trace(script=self.get_sample_script(), 776 cmds_after_breakpoint=['py-bt']) 777 self.assertMultilineMatches(bt, 778 r'''^.* 779Traceback \(most recent call first\): 780 <built-in method id of module object .*> 781 File ".*gdb_sample.py", line 10, in baz 782 id\(42\) 783 File ".*gdb_sample.py", line 7, in bar 784 baz\(a, b, c\) 785 File ".*gdb_sample.py", line 4, in foo 786 bar\(a, b, c\) 787 File ".*gdb_sample.py", line 12, in <module> 788 foo\(1, 2, 3\) 789''') 790 791 @unittest.skipIf(python_is_optimized(), 792 "Python was compiled with optimizations") 793 def test_bt_full(self): 794 'Verify that the "py-bt-full" command works' 795 bt = self.get_stack_trace(script=self.get_sample_script(), 796 cmds_after_breakpoint=['py-bt-full']) 797 self.assertMultilineMatches(bt, 798 r'''^.* 799#[0-9]+ Frame 0x-?[0-9a-f]+, for file .*gdb_sample.py, line 7, in bar \(a=1, b=2, c=3\) 800 baz\(a, b, c\) 801#[0-9]+ Frame 0x-?[0-9a-f]+, for file .*gdb_sample.py, line 4, in foo \(a=1, b=2, c=3\) 802 bar\(a, b, c\) 803#[0-9]+ Frame 0x-?[0-9a-f]+, for file .*gdb_sample.py, line 12, in <module> \(\) 804 foo\(1, 2, 3\) 805''') 806 807 def test_threads(self): 808 'Verify that "py-bt" indicates threads that are waiting for the GIL' 809 cmd = ''' 810from threading import Thread 811 812class TestThread(Thread): 813 # These threads would run forever, but we'll interrupt things with the 814 # debugger 815 def run(self): 816 i = 0 817 while 1: 818 i += 1 819 820t = {} 821for i in range(4): 822 t[i] = TestThread() 823 t[i].start() 824 825# Trigger a breakpoint on the main thread 826id(42) 827 828''' 829 # Verify with "py-bt": 830 gdb_output = self.get_stack_trace(cmd, 831 cmds_after_breakpoint=['thread apply all py-bt']) 832 self.assertIn('Waiting for the GIL', gdb_output) 833 834 # Verify with "py-bt-full": 835 gdb_output = self.get_stack_trace(cmd, 836 cmds_after_breakpoint=['thread apply all py-bt-full']) 837 self.assertIn('Waiting for the GIL', gdb_output) 838 839 @unittest.skipIf(python_is_optimized(), 840 "Python was compiled with optimizations") 841 # Some older versions of gdb will fail with 842 # "Cannot find new threads: generic error" 843 # unless we add LD_PRELOAD=PATH-TO-libpthread.so.1 as a workaround 844 def test_gc(self): 845 'Verify that "py-bt" indicates if a thread is garbage-collecting' 846 cmd = ('from gc import collect\n' 847 'id(42)\n' 848 'def foo():\n' 849 ' collect()\n' 850 'def bar():\n' 851 ' foo()\n' 852 'bar()\n') 853 # Verify with "py-bt": 854 gdb_output = self.get_stack_trace(cmd, 855 cmds_after_breakpoint=['break update_refs', 'continue', 'py-bt'], 856 ) 857 self.assertIn('Garbage-collecting', gdb_output) 858 859 # Verify with "py-bt-full": 860 gdb_output = self.get_stack_trace(cmd, 861 cmds_after_breakpoint=['break update_refs', 'continue', 'py-bt-full'], 862 ) 863 self.assertIn('Garbage-collecting', gdb_output) 864 865 @unittest.skipIf(python_is_optimized(), 866 "Python was compiled with optimizations") 867 # Some older versions of gdb will fail with 868 # "Cannot find new threads: generic error" 869 # unless we add LD_PRELOAD=PATH-TO-libpthread.so.1 as a workaround 870 def test_pycfunction(self): 871 'Verify that "py-bt" displays invocations of PyCFunction instances' 872 # Various optimizations multiply the code paths by which these are 873 # called, so test a variety of calling conventions. 874 for py_name, py_args, c_name, expected_frame_number in ( 875 ('gmtime', '', 'time_gmtime', 1), # METH_VARARGS 876 ('len', '[]', 'builtin_len', 1), # METH_O 877 ('locals', '', 'builtin_locals', 1), # METH_NOARGS 878 ('iter', '[]', 'builtin_iter', 1), # METH_FASTCALL 879 ('sorted', '[]', 'builtin_sorted', 1), # METH_FASTCALL|METH_KEYWORDS 880 ): 881 with self.subTest(c_name): 882 cmd = ('from time import gmtime\n' # (not always needed) 883 'def foo():\n' 884 f' {py_name}({py_args})\n' 885 'def bar():\n' 886 ' foo()\n' 887 'bar()\n') 888 # Verify with "py-bt": 889 gdb_output = self.get_stack_trace( 890 cmd, 891 breakpoint=c_name, 892 cmds_after_breakpoint=['bt', 'py-bt'], 893 ) 894 self.assertIn(f'<built-in method {py_name}', gdb_output) 895 896 # Verify with "py-bt-full": 897 gdb_output = self.get_stack_trace( 898 cmd, 899 breakpoint=c_name, 900 cmds_after_breakpoint=['py-bt-full'], 901 ) 902 self.assertIn( 903 f'#{expected_frame_number} <built-in method {py_name}', 904 gdb_output, 905 ) 906 907 @unittest.skipIf(python_is_optimized(), 908 "Python was compiled with optimizations") 909 def test_wrapper_call(self): 910 cmd = textwrap.dedent(''' 911 class MyList(list): 912 def __init__(self): 913 super().__init__() # wrapper_call() 914 915 id("first break point") 916 l = MyList() 917 ''') 918 cmds_after_breakpoint = ['break wrapper_call', 'continue'] 919 if CET_PROTECTION: 920 # bpo-32962: same case as in get_stack_trace(): 921 # we need an additional 'next' command in order to read 922 # arguments of the innermost function of the call stack. 923 cmds_after_breakpoint.append('next') 924 cmds_after_breakpoint.append('py-bt') 925 926 # Verify with "py-bt": 927 gdb_output = self.get_stack_trace(cmd, 928 cmds_after_breakpoint=cmds_after_breakpoint) 929 self.assertRegex(gdb_output, 930 r"<method-wrapper u?'__init__' of MyList object at ") 931 932 933class PyPrintTests(DebuggerTests): 934 @unittest.skipIf(python_is_optimized(), 935 "Python was compiled with optimizations") 936 def test_basic_command(self): 937 'Verify that the "py-print" command works' 938 bt = self.get_stack_trace(script=self.get_sample_script(), 939 cmds_after_breakpoint=['py-up', 'py-print args']) 940 self.assertMultilineMatches(bt, 941 r".*\nlocal 'args' = \(1, 2, 3\)\n.*") 942 943 @unittest.skipIf(python_is_optimized(), 944 "Python was compiled with optimizations") 945 @unittest.skipUnless(HAS_PYUP_PYDOWN, "test requires py-up/py-down commands") 946 def test_print_after_up(self): 947 bt = self.get_stack_trace(script=self.get_sample_script(), 948 cmds_after_breakpoint=['py-up', 'py-up', 'py-print c', 'py-print b', 'py-print a']) 949 self.assertMultilineMatches(bt, 950 r".*\nlocal 'c' = 3\nlocal 'b' = 2\nlocal 'a' = 1\n.*") 951 952 @unittest.skipIf(python_is_optimized(), 953 "Python was compiled with optimizations") 954 def test_printing_global(self): 955 bt = self.get_stack_trace(script=self.get_sample_script(), 956 cmds_after_breakpoint=['py-up', 'py-print __name__']) 957 self.assertMultilineMatches(bt, 958 r".*\nglobal '__name__' = '__main__'\n.*") 959 960 @unittest.skipIf(python_is_optimized(), 961 "Python was compiled with optimizations") 962 def test_printing_builtin(self): 963 bt = self.get_stack_trace(script=self.get_sample_script(), 964 cmds_after_breakpoint=['py-up', 'py-print len']) 965 self.assertMultilineMatches(bt, 966 r".*\nbuiltin 'len' = <built-in method len of module object at remote 0x-?[0-9a-f]+>\n.*") 967 968class PyLocalsTests(DebuggerTests): 969 @unittest.skipIf(python_is_optimized(), 970 "Python was compiled with optimizations") 971 def test_basic_command(self): 972 bt = self.get_stack_trace(script=self.get_sample_script(), 973 cmds_after_breakpoint=['py-up', 'py-locals']) 974 self.assertMultilineMatches(bt, 975 r".*\nargs = \(1, 2, 3\)\n.*") 976 977 @unittest.skipUnless(HAS_PYUP_PYDOWN, "test requires py-up/py-down commands") 978 @unittest.skipIf(python_is_optimized(), 979 "Python was compiled with optimizations") 980 def test_locals_after_up(self): 981 bt = self.get_stack_trace(script=self.get_sample_script(), 982 cmds_after_breakpoint=['py-up', 'py-up', 'py-locals']) 983 self.assertMultilineMatches(bt, 984 r".*\na = 1\nb = 2\nc = 3\n.*") 985 986def test_main(): 987 if support.verbose: 988 print("GDB version %s.%s:" % (gdb_major_version, gdb_minor_version)) 989 for line in gdb_version.splitlines(): 990 print(" " * 4 + line) 991 run_unittest(PrettyPrintTests, 992 PyListTests, 993 StackNavigationTests, 994 PyBtTests, 995 PyPrintTests, 996 PyLocalsTests 997 ) 998 999if __name__ == "__main__": 1000 test_main() 1001