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 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 ignore_stderr=False): 150 ''' 151 Run 'python -c SOURCE' under gdb with a breakpoint. 152 153 Support injecting commands after the breakpoint is reached 154 155 Returns the stdout from gdb 156 157 cmds_after_breakpoint: if provided, a list of strings: gdb commands 158 ''' 159 # We use "set breakpoint pending yes" to avoid blocking with a: 160 # Function "foo" not defined. 161 # Make breakpoint pending on future shared library load? (y or [n]) 162 # error, which typically happens python is dynamically linked (the 163 # breakpoints of interest are to be found in the shared library) 164 # When this happens, we still get: 165 # Function "textiowrapper_write" not defined. 166 # emitted to stderr each time, alas. 167 168 # Initially I had "--eval-command=continue" here, but removed it to 169 # avoid repeated print breakpoints when traversing hierarchical data 170 # structures 171 172 # Generate a list of commands in gdb's language: 173 commands = ['set breakpoint pending yes', 174 'break %s' % breakpoint, 175 176 # The tests assume that the first frame of printed 177 # backtrace will not contain program counter, 178 # that is however not guaranteed by gdb 179 # therefore we need to use 'set print address off' to 180 # make sure the counter is not there. For example: 181 # #0 in PyObject_Print ... 182 # is assumed, but sometimes this can be e.g. 183 # #0 0x00003fffb7dd1798 in PyObject_Print ... 184 'set print address off', 185 186 'run'] 187 188 # GDB as of 7.4 onwards can distinguish between the 189 # value of a variable at entry vs current value: 190 # http://sourceware.org/gdb/onlinedocs/gdb/Variables.html 191 # which leads to the selftests failing with errors like this: 192 # AssertionError: 'v@entry=()' != '()' 193 # Disable this: 194 if (gdb_major_version, gdb_minor_version) >= (7, 4): 195 commands += ['set print entry-values no'] 196 197 if cmds_after_breakpoint: 198 if CET_PROTECTION: 199 # bpo-32962: When Python is compiled with -mcet 200 # -fcf-protection, function arguments are unusable before 201 # running the first instruction of the function entry point. 202 # The 'next' command makes the required first step. 203 commands += ['next'] 204 commands += cmds_after_breakpoint 205 else: 206 commands += ['backtrace'] 207 208 # print commands 209 210 # Use "commands" to generate the arguments with which to invoke "gdb": 211 args = ['--eval-command=%s' % cmd for cmd in commands] 212 args += ["--args", 213 sys.executable] 214 args.extend(subprocess._args_from_interpreter_flags()) 215 216 if not import_site: 217 # -S suppresses the default 'import site' 218 args += ["-S"] 219 220 if source: 221 args += ["-c", source] 222 elif script: 223 args += [script] 224 225 # Use "args" to invoke gdb, capturing stdout, stderr: 226 out, err = run_gdb(*args, PYTHONHASHSEED=PYTHONHASHSEED) 227 228 if not ignore_stderr: 229 for line in err.splitlines(): 230 print(line, file=sys.stderr) 231 232 # bpo-34007: Sometimes some versions of the shared libraries that 233 # are part of the traceback are compiled in optimised mode and the 234 # Program Counter (PC) is not present, not allowing gdb to walk the 235 # frames back. When this happens, the Python bindings of gdb raise 236 # an exception, making the test impossible to succeed. 237 if "PC not saved" in err: 238 raise unittest.SkipTest("gdb cannot walk the frame object" 239 " because the Program Counter is" 240 " not present") 241 242 # bpo-40019: Skip the test if gdb failed to read debug information 243 # because the Python binary is optimized. 244 for pattern in ( 245 '(frame information optimized out)', 246 'Unable to read information on python frame', 247 ): 248 if pattern in out: 249 raise unittest.SkipTest(f"{pattern!r} found in gdb output") 250 251 return out 252 253 def get_gdb_repr(self, source, 254 cmds_after_breakpoint=None, 255 import_site=False): 256 # Given an input python source representation of data, 257 # run "python -c'id(DATA)'" under gdb with a breakpoint on 258 # builtin_id and scrape out gdb's representation of the "op" 259 # parameter, and verify that the gdb displays the same string 260 # 261 # Verify that the gdb displays the expected string 262 # 263 # For a nested structure, the first time we hit the breakpoint will 264 # give us the top-level structure 265 266 # NOTE: avoid decoding too much of the traceback as some 267 # undecodable characters may lurk there in optimized mode 268 # (issue #19743). 269 cmds_after_breakpoint = cmds_after_breakpoint or ["backtrace 1"] 270 gdb_output = self.get_stack_trace(source, breakpoint=BREAKPOINT_FN, 271 cmds_after_breakpoint=cmds_after_breakpoint, 272 import_site=import_site) 273 # gdb can insert additional '\n' and space characters in various places 274 # in its output, depending on the width of the terminal it's connected 275 # to (using its "wrap_here" function) 276 m = re.search( 277 # Match '#0 builtin_id(self=..., v=...)' 278 r'#0\s+builtin_id\s+\(self\=.*,\s+v=\s*(.*?)?\)' 279 # Match ' at Python/bltinmodule.c'. 280 # bpo-38239: builtin_id() is defined in Python/bltinmodule.c, 281 # but accept any "Directory\file.c" to support Link Time 282 # Optimization (LTO). 283 r'\s+at\s+\S*[A-Za-z]+/[A-Za-z0-9_-]+\.c', 284 gdb_output, re.DOTALL) 285 if not m: 286 self.fail('Unexpected gdb output: %r\n%s' % (gdb_output, gdb_output)) 287 return m.group(1), gdb_output 288 289 def assertEndsWith(self, actual, exp_end): 290 '''Ensure that the given "actual" string ends with "exp_end"''' 291 self.assertTrue(actual.endswith(exp_end), 292 msg='%r did not end with %r' % (actual, exp_end)) 293 294 def assertMultilineMatches(self, actual, pattern): 295 m = re.match(pattern, actual, re.DOTALL) 296 if not m: 297 self.fail(msg='%r did not match %r' % (actual, pattern)) 298 299 def get_sample_script(self): 300 return findfile('gdb_sample.py') 301 302class PrettyPrintTests(DebuggerTests): 303 def test_getting_backtrace(self): 304 gdb_output = self.get_stack_trace('id(42)') 305 self.assertTrue(BREAKPOINT_FN in gdb_output) 306 307 def assertGdbRepr(self, val, exp_repr=None): 308 # Ensure that gdb's rendering of the value in a debugged process 309 # matches repr(value) in this process: 310 gdb_repr, gdb_output = self.get_gdb_repr('id(' + ascii(val) + ')') 311 if not exp_repr: 312 exp_repr = repr(val) 313 self.assertEqual(gdb_repr, exp_repr, 314 ('%r did not equal expected %r; full output was:\n%s' 315 % (gdb_repr, exp_repr, gdb_output))) 316 317 def test_int(self): 318 'Verify the pretty-printing of various int values' 319 self.assertGdbRepr(42) 320 self.assertGdbRepr(0) 321 self.assertGdbRepr(-7) 322 self.assertGdbRepr(1000000000000) 323 self.assertGdbRepr(-1000000000000000) 324 325 def test_singletons(self): 326 'Verify the pretty-printing of True, False and None' 327 self.assertGdbRepr(True) 328 self.assertGdbRepr(False) 329 self.assertGdbRepr(None) 330 331 def test_dicts(self): 332 'Verify the pretty-printing of dictionaries' 333 self.assertGdbRepr({}) 334 self.assertGdbRepr({'foo': 'bar'}, "{'foo': 'bar'}") 335 # Python preserves insertion order since 3.6 336 self.assertGdbRepr({'foo': 'bar', 'douglas': 42}, "{'foo': 'bar', 'douglas': 42}") 337 338 def test_lists(self): 339 'Verify the pretty-printing of lists' 340 self.assertGdbRepr([]) 341 self.assertGdbRepr(list(range(5))) 342 343 def test_bytes(self): 344 'Verify the pretty-printing of bytes' 345 self.assertGdbRepr(b'') 346 self.assertGdbRepr(b'And now for something hopefully the same') 347 self.assertGdbRepr(b'string with embedded NUL here \0 and then some more text') 348 self.assertGdbRepr(b'this is a tab:\t' 349 b' this is a slash-N:\n' 350 b' this is a slash-R:\r' 351 ) 352 353 self.assertGdbRepr(b'this is byte 255:\xff and byte 128:\x80') 354 355 self.assertGdbRepr(bytes([b for b in range(255)])) 356 357 def test_strings(self): 358 'Verify the pretty-printing of unicode strings' 359 # We cannot simply call locale.getpreferredencoding() here, 360 # as GDB might have been linked against a different version 361 # of Python with a different encoding and coercion policy 362 # with respect to PEP 538 and PEP 540. 363 out, err = run_gdb( 364 '--eval-command', 365 'python import locale; print(locale.getpreferredencoding())') 366 367 encoding = out.rstrip() 368 if err or not encoding: 369 raise RuntimeError( 370 f'unable to determine the preferred encoding ' 371 f'of embedded Python in GDB: {err}') 372 373 def check_repr(text): 374 try: 375 text.encode(encoding) 376 except UnicodeEncodeError: 377 self.assertGdbRepr(text, ascii(text)) 378 else: 379 self.assertGdbRepr(text) 380 381 self.assertGdbRepr('') 382 self.assertGdbRepr('And now for something hopefully the same') 383 self.assertGdbRepr('string with embedded NUL here \0 and then some more text') 384 385 # Test printing a single character: 386 # U+2620 SKULL AND CROSSBONES 387 check_repr('\u2620') 388 389 # Test printing a Japanese unicode string 390 # (I believe this reads "mojibake", using 3 characters from the CJK 391 # Unified Ideographs area, followed by U+3051 HIRAGANA LETTER KE) 392 check_repr('\u6587\u5b57\u5316\u3051') 393 394 # Test a character outside the BMP: 395 # U+1D121 MUSICAL SYMBOL C CLEF 396 # This is: 397 # UTF-8: 0xF0 0x9D 0x84 0xA1 398 # UTF-16: 0xD834 0xDD21 399 check_repr(chr(0x1D121)) 400 401 def test_tuples(self): 402 'Verify the pretty-printing of tuples' 403 self.assertGdbRepr(tuple(), '()') 404 self.assertGdbRepr((1,), '(1,)') 405 self.assertGdbRepr(('foo', 'bar', 'baz')) 406 407 def test_sets(self): 408 'Verify the pretty-printing of sets' 409 if (gdb_major_version, gdb_minor_version) < (7, 3): 410 self.skipTest("pretty-printing of sets needs gdb 7.3 or later") 411 self.assertGdbRepr(set(), "set()") 412 self.assertGdbRepr(set(['a']), "{'a'}") 413 # PYTHONHASHSEED is need to get the exact frozenset item order 414 if not sys.flags.ignore_environment: 415 self.assertGdbRepr(set(['a', 'b']), "{'a', 'b'}") 416 self.assertGdbRepr(set([4, 5, 6]), "{4, 5, 6}") 417 418 # Ensure that we handle sets containing the "dummy" key value, 419 # which happens on deletion: 420 gdb_repr, gdb_output = self.get_gdb_repr('''s = set(['a','b']) 421s.remove('a') 422id(s)''') 423 self.assertEqual(gdb_repr, "{'b'}") 424 425 def test_frozensets(self): 426 'Verify the pretty-printing of frozensets' 427 if (gdb_major_version, gdb_minor_version) < (7, 3): 428 self.skipTest("pretty-printing of frozensets needs gdb 7.3 or later") 429 self.assertGdbRepr(frozenset(), "frozenset()") 430 self.assertGdbRepr(frozenset(['a']), "frozenset({'a'})") 431 # PYTHONHASHSEED is need to get the exact frozenset item order 432 if not sys.flags.ignore_environment: 433 self.assertGdbRepr(frozenset(['a', 'b']), "frozenset({'a', 'b'})") 434 self.assertGdbRepr(frozenset([4, 5, 6]), "frozenset({4, 5, 6})") 435 436 def test_exceptions(self): 437 # Test a RuntimeError 438 gdb_repr, gdb_output = self.get_gdb_repr(''' 439try: 440 raise RuntimeError("I am an error") 441except RuntimeError as e: 442 id(e) 443''') 444 self.assertEqual(gdb_repr, 445 "RuntimeError('I am an error',)") 446 447 448 # Test division by zero: 449 gdb_repr, gdb_output = self.get_gdb_repr(''' 450try: 451 a = 1 / 0 452except ZeroDivisionError as e: 453 id(e) 454''') 455 self.assertEqual(gdb_repr, 456 "ZeroDivisionError('division by zero',)") 457 458 def test_modern_class(self): 459 'Verify the pretty-printing of new-style class instances' 460 gdb_repr, gdb_output = self.get_gdb_repr(''' 461class Foo: 462 pass 463foo = Foo() 464foo.an_int = 42 465id(foo)''') 466 m = re.match(r'<Foo\(an_int=42\) at remote 0x-?[0-9a-f]+>', gdb_repr) 467 self.assertTrue(m, 468 msg='Unexpected new-style class rendering %r' % gdb_repr) 469 470 def test_subclassing_list(self): 471 'Verify the pretty-printing of an instance of a list subclass' 472 gdb_repr, gdb_output = self.get_gdb_repr(''' 473class Foo(list): 474 pass 475foo = Foo() 476foo += [1, 2, 3] 477foo.an_int = 42 478id(foo)''') 479 m = re.match(r'<Foo\(an_int=42\) at remote 0x-?[0-9a-f]+>', gdb_repr) 480 481 self.assertTrue(m, 482 msg='Unexpected new-style class rendering %r' % gdb_repr) 483 484 def test_subclassing_tuple(self): 485 'Verify the pretty-printing of an instance of a tuple subclass' 486 # This should exercise the negative tp_dictoffset code in the 487 # new-style class support 488 gdb_repr, gdb_output = self.get_gdb_repr(''' 489class Foo(tuple): 490 pass 491foo = Foo((1, 2, 3)) 492foo.an_int = 42 493id(foo)''') 494 m = re.match(r'<Foo\(an_int=42\) at remote 0x-?[0-9a-f]+>', gdb_repr) 495 496 self.assertTrue(m, 497 msg='Unexpected new-style class rendering %r' % gdb_repr) 498 499 def assertSane(self, source, corruption, exprepr=None): 500 '''Run Python under gdb, corrupting variables in the inferior process 501 immediately before taking a backtrace. 502 503 Verify that the variable's representation is the expected failsafe 504 representation''' 505 if corruption: 506 cmds_after_breakpoint=[corruption, 'backtrace'] 507 else: 508 cmds_after_breakpoint=['backtrace'] 509 510 gdb_repr, gdb_output = \ 511 self.get_gdb_repr(source, 512 cmds_after_breakpoint=cmds_after_breakpoint) 513 if exprepr: 514 if gdb_repr == exprepr: 515 # gdb managed to print the value in spite of the corruption; 516 # this is good (see http://bugs.python.org/issue8330) 517 return 518 519 # Match anything for the type name; 0xDEADBEEF could point to 520 # something arbitrary (see http://bugs.python.org/issue8330) 521 pattern = '<.* at remote 0x-?[0-9a-f]+>' 522 523 m = re.match(pattern, gdb_repr) 524 if not m: 525 self.fail('Unexpected gdb representation: %r\n%s' % \ 526 (gdb_repr, gdb_output)) 527 528 def test_NULL_ptr(self): 529 'Ensure that a NULL PyObject* is handled gracefully' 530 gdb_repr, gdb_output = ( 531 self.get_gdb_repr('id(42)', 532 cmds_after_breakpoint=['set variable v=0', 533 'backtrace']) 534 ) 535 536 self.assertEqual(gdb_repr, '0x0') 537 538 def test_NULL_ob_type(self): 539 'Ensure that a PyObject* with NULL ob_type is handled gracefully' 540 self.assertSane('id(42)', 541 'set v->ob_type=0') 542 543 def test_corrupt_ob_type(self): 544 'Ensure that a PyObject* with a corrupt ob_type is handled gracefully' 545 self.assertSane('id(42)', 546 'set v->ob_type=0xDEADBEEF', 547 exprepr='42') 548 549 def test_corrupt_tp_flags(self): 550 'Ensure that a PyObject* with a type with corrupt tp_flags is handled' 551 self.assertSane('id(42)', 552 'set v->ob_type->tp_flags=0x0', 553 exprepr='42') 554 555 def test_corrupt_tp_name(self): 556 'Ensure that a PyObject* with a type with corrupt tp_name is handled' 557 self.assertSane('id(42)', 558 'set v->ob_type->tp_name=0xDEADBEEF', 559 exprepr='42') 560 561 def test_builtins_help(self): 562 'Ensure that the new-style class _Helper in site.py can be handled' 563 564 if sys.flags.no_site: 565 self.skipTest("need site module, but -S option was used") 566 567 # (this was the issue causing tracebacks in 568 # http://bugs.python.org/issue8032#msg100537 ) 569 gdb_repr, gdb_output = self.get_gdb_repr('id(__builtins__.help)', import_site=True) 570 571 m = re.match(r'<_Helper\(\) at remote 0x-?[0-9a-f]+>', gdb_repr) 572 self.assertTrue(m, 573 msg='Unexpected rendering %r' % gdb_repr) 574 575 def test_selfreferential_list(self): 576 '''Ensure that a reference loop involving a list doesn't lead proxyval 577 into an infinite loop:''' 578 gdb_repr, gdb_output = \ 579 self.get_gdb_repr("a = [3, 4, 5] ; a.append(a) ; id(a)") 580 self.assertEqual(gdb_repr, '[3, 4, 5, [...]]') 581 582 gdb_repr, gdb_output = \ 583 self.get_gdb_repr("a = [3, 4, 5] ; b = [a] ; a.append(b) ; id(a)") 584 self.assertEqual(gdb_repr, '[3, 4, 5, [[...]]]') 585 586 def test_selfreferential_dict(self): 587 '''Ensure that a reference loop involving a dict doesn't lead proxyval 588 into an infinite loop:''' 589 gdb_repr, gdb_output = \ 590 self.get_gdb_repr("a = {} ; b = {'bar':a} ; a['foo'] = b ; id(a)") 591 592 self.assertEqual(gdb_repr, "{'foo': {'bar': {...}}}") 593 594 def test_selfreferential_old_style_instance(self): 595 gdb_repr, gdb_output = \ 596 self.get_gdb_repr(''' 597class Foo: 598 pass 599foo = Foo() 600foo.an_attr = foo 601id(foo)''') 602 self.assertTrue(re.match(r'<Foo\(an_attr=<\.\.\.>\) at remote 0x-?[0-9a-f]+>', 603 gdb_repr), 604 'Unexpected gdb representation: %r\n%s' % \ 605 (gdb_repr, gdb_output)) 606 607 def test_selfreferential_new_style_instance(self): 608 gdb_repr, gdb_output = \ 609 self.get_gdb_repr(''' 610class Foo(object): 611 pass 612foo = Foo() 613foo.an_attr = foo 614id(foo)''') 615 self.assertTrue(re.match(r'<Foo\(an_attr=<\.\.\.>\) at remote 0x-?[0-9a-f]+>', 616 gdb_repr), 617 'Unexpected gdb representation: %r\n%s' % \ 618 (gdb_repr, gdb_output)) 619 620 gdb_repr, gdb_output = \ 621 self.get_gdb_repr(''' 622class Foo(object): 623 pass 624a = Foo() 625b = Foo() 626a.an_attr = b 627b.an_attr = a 628id(a)''') 629 self.assertTrue(re.match(r'<Foo\(an_attr=<Foo\(an_attr=<\.\.\.>\) at remote 0x-?[0-9a-f]+>\) at remote 0x-?[0-9a-f]+>', 630 gdb_repr), 631 'Unexpected gdb representation: %r\n%s' % \ 632 (gdb_repr, gdb_output)) 633 634 def test_truncation(self): 635 'Verify that very long output is truncated' 636 gdb_repr, gdb_output = self.get_gdb_repr('id(list(range(1000)))') 637 self.assertEqual(gdb_repr, 638 "[0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, " 639 "14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, " 640 "27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, " 641 "40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, " 642 "53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65, " 643 "66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, " 644 "79, 80, 81, 82, 83, 84, 85, 86, 87, 88, 89, 90, 91, " 645 "92, 93, 94, 95, 96, 97, 98, 99, 100, 101, 102, 103, " 646 "104, 105, 106, 107, 108, 109, 110, 111, 112, 113, " 647 "114, 115, 116, 117, 118, 119, 120, 121, 122, 123, " 648 "124, 125, 126, 127, 128, 129, 130, 131, 132, 133, " 649 "134, 135, 136, 137, 138, 139, 140, 141, 142, 143, " 650 "144, 145, 146, 147, 148, 149, 150, 151, 152, 153, " 651 "154, 155, 156, 157, 158, 159, 160, 161, 162, 163, " 652 "164, 165, 166, 167, 168, 169, 170, 171, 172, 173, " 653 "174, 175, 176, 177, 178, 179, 180, 181, 182, 183, " 654 "184, 185, 186, 187, 188, 189, 190, 191, 192, 193, " 655 "194, 195, 196, 197, 198, 199, 200, 201, 202, 203, " 656 "204, 205, 206, 207, 208, 209, 210, 211, 212, 213, " 657 "214, 215, 216, 217, 218, 219, 220, 221, 222, 223, " 658 "224, 225, 226...(truncated)") 659 self.assertEqual(len(gdb_repr), 660 1024 + len('...(truncated)')) 661 662 def test_builtin_method(self): 663 gdb_repr, gdb_output = self.get_gdb_repr('import sys; id(sys.stdout.readlines)') 664 self.assertTrue(re.match(r'<built-in method readlines of _io.TextIOWrapper object at remote 0x-?[0-9a-f]+>', 665 gdb_repr), 666 'Unexpected gdb representation: %r\n%s' % \ 667 (gdb_repr, gdb_output)) 668 669 def test_frames(self): 670 gdb_output = self.get_stack_trace(''' 671import sys 672def foo(a, b, c): 673 return sys._getframe(0) 674 675f = foo(3, 4, 5) 676id(f)''', 677 breakpoint='builtin_id', 678 cmds_after_breakpoint=['print (PyFrameObject*)v'] 679 ) 680 self.assertTrue(re.match(r'.*\s+\$1 =\s+Frame 0x-?[0-9a-f]+, for file <string>, line 4, in foo \(a=3.*', 681 gdb_output, 682 re.DOTALL), 683 'Unexpected gdb representation: %r\n%s' % (gdb_output, gdb_output)) 684 685@unittest.skipIf(python_is_optimized(), 686 "Python was compiled with optimizations") 687class PyListTests(DebuggerTests): 688 def assertListing(self, expected, actual): 689 self.assertEndsWith(actual, expected) 690 691 def test_basic_command(self): 692 'Verify that the "py-list" command works' 693 bt = self.get_stack_trace(script=self.get_sample_script(), 694 cmds_after_breakpoint=['py-list']) 695 696 self.assertListing(' 5 \n' 697 ' 6 def bar(a, b, c):\n' 698 ' 7 baz(a, b, c)\n' 699 ' 8 \n' 700 ' 9 def baz(*args):\n' 701 ' >10 id(42)\n' 702 ' 11 \n' 703 ' 12 foo(1, 2, 3)\n', 704 bt) 705 706 def test_one_abs_arg(self): 707 'Verify the "py-list" command with one absolute argument' 708 bt = self.get_stack_trace(script=self.get_sample_script(), 709 cmds_after_breakpoint=['py-list 9']) 710 711 self.assertListing(' 9 def baz(*args):\n' 712 ' >10 id(42)\n' 713 ' 11 \n' 714 ' 12 foo(1, 2, 3)\n', 715 bt) 716 717 def test_two_abs_args(self): 718 'Verify the "py-list" command with two absolute arguments' 719 bt = self.get_stack_trace(script=self.get_sample_script(), 720 cmds_after_breakpoint=['py-list 1,3']) 721 722 self.assertListing(' 1 # Sample script for use by test_gdb.py\n' 723 ' 2 \n' 724 ' 3 def foo(a, b, c):\n', 725 bt) 726 727SAMPLE_WITH_C_CALL = """ 728 729from _testcapi import pyobject_fastcall 730 731def foo(a, b, c): 732 bar(a, b, c) 733 734def bar(a, b, c): 735 pyobject_fastcall(baz, (a, b, c)) 736 737def baz(*args): 738 id(42) 739 740foo(1, 2, 3) 741 742""" 743 744 745class StackNavigationTests(DebuggerTests): 746 @unittest.skipUnless(HAS_PYUP_PYDOWN, "test requires py-up/py-down commands") 747 @unittest.skipIf(python_is_optimized(), 748 "Python was compiled with optimizations") 749 def test_pyup_command(self): 750 'Verify that the "py-up" command works' 751 bt = self.get_stack_trace(source=SAMPLE_WITH_C_CALL, 752 cmds_after_breakpoint=['py-up', 'py-up']) 753 self.assertMultilineMatches(bt, 754 r'''^.* 755#[0-9]+ Frame 0x-?[0-9a-f]+, for file <string>, line 12, in baz \(args=\(1, 2, 3\)\) 756#[0-9]+ <built-in method pyobject_fastcall of module object at remote 0x[0-9a-f]+> 757$''') 758 759 @unittest.skipUnless(HAS_PYUP_PYDOWN, "test requires py-up/py-down commands") 760 def test_down_at_bottom(self): 761 'Verify handling of "py-down" at the bottom of the stack' 762 bt = self.get_stack_trace(script=self.get_sample_script(), 763 cmds_after_breakpoint=['py-down']) 764 self.assertEndsWith(bt, 765 'Unable to find a newer python frame\n') 766 767 @unittest.skipUnless(HAS_PYUP_PYDOWN, "test requires py-up/py-down commands") 768 def test_up_at_top(self): 769 'Verify handling of "py-up" at the top of the stack' 770 bt = self.get_stack_trace(script=self.get_sample_script(), 771 cmds_after_breakpoint=['py-up'] * 5) 772 self.assertEndsWith(bt, 773 'Unable to find an older python frame\n') 774 775 @unittest.skipUnless(HAS_PYUP_PYDOWN, "test requires py-up/py-down commands") 776 @unittest.skipIf(python_is_optimized(), 777 "Python was compiled with optimizations") 778 def test_up_then_down(self): 779 'Verify "py-up" followed by "py-down"' 780 bt = self.get_stack_trace(source=SAMPLE_WITH_C_CALL, 781 cmds_after_breakpoint=['py-up', 'py-up', 'py-down']) 782 self.assertMultilineMatches(bt, 783 r'''^.* 784#[0-9]+ Frame 0x-?[0-9a-f]+, for file <string>, line 12, in baz \(args=\(1, 2, 3\)\) 785#[0-9]+ <built-in method pyobject_fastcall of module object at remote 0x[0-9a-f]+> 786#[0-9]+ Frame 0x-?[0-9a-f]+, for file <string>, line 12, in baz \(args=\(1, 2, 3\)\) 787$''') 788 789class PyBtTests(DebuggerTests): 790 @unittest.skipIf(python_is_optimized(), 791 "Python was compiled with optimizations") 792 def test_bt(self): 793 'Verify that the "py-bt" command works' 794 bt = self.get_stack_trace(script=self.get_sample_script(), 795 cmds_after_breakpoint=['py-bt']) 796 self.assertMultilineMatches(bt, 797 r'''^.* 798Traceback \(most recent call first\): 799 <built-in method id of module object .*> 800 File ".*gdb_sample.py", line 10, in baz 801 id\(42\) 802 File ".*gdb_sample.py", line 7, in bar 803 baz\(a, b, c\) 804 File ".*gdb_sample.py", line 4, in foo 805 bar\(a=a, b=b, c=c\) 806 File ".*gdb_sample.py", line 12, in <module> 807 foo\(1, 2, 3\) 808''') 809 810 @unittest.skipIf(python_is_optimized(), 811 "Python was compiled with optimizations") 812 def test_bt_full(self): 813 'Verify that the "py-bt-full" command works' 814 bt = self.get_stack_trace(script=self.get_sample_script(), 815 cmds_after_breakpoint=['py-bt-full']) 816 self.assertMultilineMatches(bt, 817 r'''^.* 818#[0-9]+ Frame 0x-?[0-9a-f]+, for file .*gdb_sample.py, line 7, in bar \(a=1, b=2, c=3\) 819 baz\(a, b, c\) 820#[0-9]+ Frame 0x-?[0-9a-f]+, for file .*gdb_sample.py, line 4, in foo \(a=1, b=2, c=3\) 821 bar\(a=a, b=b, c=c\) 822#[0-9]+ Frame 0x-?[0-9a-f]+, for file .*gdb_sample.py, line 12, in <module> \(\) 823 foo\(1, 2, 3\) 824''') 825 826 @unittest.skipIf(python_is_optimized(), 827 "Python was compiled with optimizations") 828 def test_threads(self): 829 'Verify that "py-bt" indicates threads that are waiting for the GIL' 830 cmd = ''' 831from threading import Thread 832 833class TestThread(Thread): 834 # These threads would run forever, but we'll interrupt things with the 835 # debugger 836 def run(self): 837 i = 0 838 while 1: 839 i += 1 840 841t = {} 842for i in range(4): 843 t[i] = TestThread() 844 t[i].start() 845 846# Trigger a breakpoint on the main thread 847id(42) 848 849''' 850 # Verify with "py-bt": 851 gdb_output = self.get_stack_trace(cmd, 852 cmds_after_breakpoint=['thread apply all py-bt']) 853 self.assertIn('Waiting for the GIL', gdb_output) 854 855 # Verify with "py-bt-full": 856 gdb_output = self.get_stack_trace(cmd, 857 cmds_after_breakpoint=['thread apply all py-bt-full']) 858 self.assertIn('Waiting for the GIL', gdb_output) 859 860 @unittest.skipIf(python_is_optimized(), 861 "Python was compiled with optimizations") 862 # Some older versions of gdb will fail with 863 # "Cannot find new threads: generic error" 864 # unless we add LD_PRELOAD=PATH-TO-libpthread.so.1 as a workaround 865 def test_gc(self): 866 'Verify that "py-bt" indicates if a thread is garbage-collecting' 867 cmd = ('from gc import collect\n' 868 'id(42)\n' 869 'def foo():\n' 870 ' collect()\n' 871 'def bar():\n' 872 ' foo()\n' 873 'bar()\n') 874 # Verify with "py-bt": 875 gdb_output = self.get_stack_trace(cmd, 876 cmds_after_breakpoint=['break update_refs', 'continue', 'py-bt'], 877 ) 878 self.assertIn('Garbage-collecting', gdb_output) 879 880 # Verify with "py-bt-full": 881 gdb_output = self.get_stack_trace(cmd, 882 cmds_after_breakpoint=['break update_refs', 'continue', 'py-bt-full'], 883 ) 884 self.assertIn('Garbage-collecting', gdb_output) 885 886 887 @unittest.skipIf(python_is_optimized(), 888 "Python was compiled with optimizations") 889 # Some older versions of gdb will fail with 890 # "Cannot find new threads: generic error" 891 # unless we add LD_PRELOAD=PATH-TO-libpthread.so.1 as a workaround 892 # 893 # gdb will also generate many erroneous errors such as: 894 # Function "meth_varargs" not defined. 895 # This is because we are calling functions from an "external" module 896 # (_testcapimodule) rather than compiled-in functions. It seems difficult 897 # to suppress these. See also the comment in DebuggerTests.get_stack_trace 898 def test_pycfunction(self): 899 'Verify that "py-bt" displays invocations of PyCFunction instances' 900 # Various optimizations multiply the code paths by which these are 901 # called, so test a variety of calling conventions. 902 for func_name, args, expected_frame in ( 903 ('meth_varargs', '', 1), 904 ('meth_varargs_keywords', '', 1), 905 ('meth_o', '[]', 1), 906 ('meth_noargs', '', 1), 907 ('meth_fastcall', '', 1), 908 ('meth_fastcall_keywords', '', 1), 909 ): 910 for obj in ( 911 '_testcapi', 912 '_testcapi.MethClass', 913 '_testcapi.MethClass()', 914 '_testcapi.MethStatic()', 915 916 # XXX: bound methods don't yet give nice tracebacks 917 # '_testcapi.MethInstance()', 918 ): 919 with self.subTest(f'{obj}.{func_name}'): 920 cmd = textwrap.dedent(f''' 921 import _testcapi 922 def foo(): 923 {obj}.{func_name}({args}) 924 def bar(): 925 foo() 926 bar() 927 ''') 928 # Verify with "py-bt": 929 gdb_output = self.get_stack_trace( 930 cmd, 931 breakpoint=func_name, 932 cmds_after_breakpoint=['bt', 'py-bt'], 933 # bpo-45207: Ignore 'Function "meth_varargs" not 934 # defined.' message in stderr. 935 ignore_stderr=True, 936 ) 937 self.assertIn(f'<built-in method {func_name}', gdb_output) 938 939 # Verify with "py-bt-full": 940 gdb_output = self.get_stack_trace( 941 cmd, 942 breakpoint=func_name, 943 cmds_after_breakpoint=['py-bt-full'], 944 # bpo-45207: Ignore 'Function "meth_varargs" not 945 # defined.' message in stderr. 946 ignore_stderr=True, 947 ) 948 self.assertIn( 949 f'#{expected_frame} <built-in method {func_name}', 950 gdb_output, 951 ) 952 953 @unittest.skipIf(python_is_optimized(), 954 "Python was compiled with optimizations") 955 def test_wrapper_call(self): 956 cmd = textwrap.dedent(''' 957 class MyList(list): 958 def __init__(self): 959 super().__init__() # wrapper_call() 960 961 id("first break point") 962 l = MyList() 963 ''') 964 cmds_after_breakpoint = ['break wrapper_call', 'continue'] 965 if CET_PROTECTION: 966 # bpo-32962: same case as in get_stack_trace(): 967 # we need an additional 'next' command in order to read 968 # arguments of the innermost function of the call stack. 969 cmds_after_breakpoint.append('next') 970 cmds_after_breakpoint.append('py-bt') 971 972 # Verify with "py-bt": 973 gdb_output = self.get_stack_trace(cmd, 974 cmds_after_breakpoint=cmds_after_breakpoint) 975 self.assertRegex(gdb_output, 976 r"<method-wrapper u?'__init__' of MyList object at ") 977 978class PyPrintTests(DebuggerTests): 979 @unittest.skipIf(python_is_optimized(), 980 "Python was compiled with optimizations") 981 def test_basic_command(self): 982 'Verify that the "py-print" command works' 983 bt = self.get_stack_trace(source=SAMPLE_WITH_C_CALL, 984 cmds_after_breakpoint=['py-up', 'py-print args']) 985 self.assertMultilineMatches(bt, 986 r".*\nlocal 'args' = \(1, 2, 3\)\n.*") 987 988 @unittest.skipIf(python_is_optimized(), 989 "Python was compiled with optimizations") 990 @unittest.skipUnless(HAS_PYUP_PYDOWN, "test requires py-up/py-down commands") 991 def test_print_after_up(self): 992 bt = self.get_stack_trace(source=SAMPLE_WITH_C_CALL, 993 cmds_after_breakpoint=['py-up', 'py-up', 'py-print c', 'py-print b', 'py-print a']) 994 self.assertMultilineMatches(bt, 995 r".*\nlocal 'c' = 3\nlocal 'b' = 2\nlocal 'a' = 1\n.*") 996 997 @unittest.skipIf(python_is_optimized(), 998 "Python was compiled with optimizations") 999 def test_printing_global(self): 1000 bt = self.get_stack_trace(script=self.get_sample_script(), 1001 cmds_after_breakpoint=['py-up', 'py-print __name__']) 1002 self.assertMultilineMatches(bt, 1003 r".*\nglobal '__name__' = '__main__'\n.*") 1004 1005 @unittest.skipIf(python_is_optimized(), 1006 "Python was compiled with optimizations") 1007 def test_printing_builtin(self): 1008 bt = self.get_stack_trace(script=self.get_sample_script(), 1009 cmds_after_breakpoint=['py-up', 'py-print len']) 1010 self.assertMultilineMatches(bt, 1011 r".*\nbuiltin 'len' = <built-in method len of module object at remote 0x-?[0-9a-f]+>\n.*") 1012 1013class PyLocalsTests(DebuggerTests): 1014 @unittest.skipIf(python_is_optimized(), 1015 "Python was compiled with optimizations") 1016 def test_basic_command(self): 1017 bt = self.get_stack_trace(script=self.get_sample_script(), 1018 cmds_after_breakpoint=['py-up', 'py-locals']) 1019 self.assertMultilineMatches(bt, 1020 r".*\nargs = \(1, 2, 3\)\n.*") 1021 1022 @unittest.skipUnless(HAS_PYUP_PYDOWN, "test requires py-up/py-down commands") 1023 @unittest.skipIf(python_is_optimized(), 1024 "Python was compiled with optimizations") 1025 def test_locals_after_up(self): 1026 bt = self.get_stack_trace(script=self.get_sample_script(), 1027 cmds_after_breakpoint=['py-up', 'py-up', 'py-locals']) 1028 self.assertMultilineMatches(bt, 1029 r'''^.* 1030Locals for foo 1031a = 1 1032b = 2 1033c = 3 1034Locals for <module> 1035.*$''') 1036 1037 1038def setUpModule(): 1039 if support.verbose: 1040 print("GDB version %s.%s:" % (gdb_major_version, gdb_minor_version)) 1041 for line in gdb_version.splitlines(): 1042 print(" " * 4 + line) 1043 1044 1045if __name__ == "__main__": 1046 unittest.main() 1047