| 1 | """A pure-Python Python bytecode interpreter."""
|
| 2 | # Based on:
|
| 3 | # pyvm2 by Paul Swartz (z3p), from http://www.twistedmatrix.com/users/z3p/
|
| 4 |
|
| 5 | from __future__ import print_function, division
|
| 6 | import dis
|
| 7 | import inspect
|
| 8 | import linecache
|
| 9 | import logging
|
| 10 | import operator
|
| 11 | import sys
|
| 12 | import types
|
| 13 |
|
| 14 | import six
|
| 15 | from six.moves import reprlib
|
| 16 |
|
| 17 | PY3, PY2 = six.PY3, not six.PY3
|
| 18 |
|
| 19 | from pyobj import Frame, Block, Method, Function, Generator
|
| 20 |
|
| 21 | log = logging.getLogger(__name__)
|
| 22 |
|
| 23 | # Create a repr that won't overflow.
|
| 24 | repr_obj = reprlib.Repr()
|
| 25 | repr_obj.maxother = 120
|
| 26 | repper = repr_obj.repr
|
| 27 |
|
| 28 |
|
| 29 | class VirtualMachineError(Exception):
|
| 30 | """For raising errors in the operation of the VM."""
|
| 31 | pass
|
| 32 |
|
| 33 |
|
| 34 | class VirtualMachine(object):
|
| 35 | def __init__(self):
|
| 36 | # The call stack of frames.
|
| 37 | self.frames = []
|
| 38 | # The current frame.
|
| 39 | self.frame = None
|
| 40 | self.return_value = None
|
| 41 | self.last_exception = None
|
| 42 |
|
| 43 | def top(self):
|
| 44 | """Return the value at the top of the stack, with no changes."""
|
| 45 | return self.frame.stack[-1]
|
| 46 |
|
| 47 | def pop(self, i=0):
|
| 48 | """Pop a value from the stack.
|
| 49 |
|
| 50 | Default to the top of the stack, but `i` can be a count from the top
|
| 51 | instead.
|
| 52 |
|
| 53 | """
|
| 54 | return self.frame.stack.pop(-1-i)
|
| 55 |
|
| 56 | def push(self, *vals):
|
| 57 | """Push values onto the value stack."""
|
| 58 | self.frame.stack.extend(vals)
|
| 59 |
|
| 60 | def popn(self, n):
|
| 61 | """Pop a number of values from the value stack.
|
| 62 |
|
| 63 | A list of `n` values is returned, the deepest value first.
|
| 64 |
|
| 65 | """
|
| 66 | if n:
|
| 67 | ret = self.frame.stack[-n:]
|
| 68 | self.frame.stack[-n:] = []
|
| 69 | return ret
|
| 70 | else:
|
| 71 | return []
|
| 72 |
|
| 73 | def peek(self, n):
|
| 74 | """Get a value `n` entries down in the stack, without changing the stack."""
|
| 75 | return self.frame.stack[-n]
|
| 76 |
|
| 77 | def jump(self, jump):
|
| 78 | """Move the bytecode pointer to `jump`, so it will execute next."""
|
| 79 | self.frame.f_lasti = jump
|
| 80 |
|
| 81 | def push_block(self, type, handler=None, level=None):
|
| 82 | if level is None:
|
| 83 | level = len(self.frame.stack)
|
| 84 | self.frame.block_stack.append(Block(type, handler, level))
|
| 85 |
|
| 86 | def pop_block(self):
|
| 87 | return self.frame.block_stack.pop()
|
| 88 |
|
| 89 | def make_frame(self, code, callargs={}, f_globals=None, f_locals=None):
|
| 90 | log.info("make_frame: code=%r, callargs=%s" % (code, repper(callargs)))
|
| 91 | if f_globals is not None:
|
| 92 | f_globals = f_globals
|
| 93 | if f_locals is None:
|
| 94 | f_locals = f_globals
|
| 95 | elif self.frames:
|
| 96 | f_globals = self.frame.f_globals
|
| 97 | f_locals = {}
|
| 98 | else:
|
| 99 | f_globals = f_locals = {
|
| 100 | '__builtins__': __builtins__,
|
| 101 | '__name__': '__main__',
|
| 102 | '__doc__': None,
|
| 103 | '__package__': None,
|
| 104 | }
|
| 105 | f_locals.update(callargs)
|
| 106 | frame = Frame(code, f_globals, f_locals, self.frame)
|
| 107 | return frame
|
| 108 |
|
| 109 | def push_frame(self, frame):
|
| 110 | self.frames.append(frame)
|
| 111 | self.frame = frame
|
| 112 |
|
| 113 | def pop_frame(self):
|
| 114 | self.frames.pop()
|
| 115 | if self.frames:
|
| 116 | self.frame = self.frames[-1]
|
| 117 | else:
|
| 118 | self.frame = None
|
| 119 |
|
| 120 | def print_frames(self):
|
| 121 | """Print the call stack, for debugging."""
|
| 122 | for f in self.frames:
|
| 123 | filename = f.f_code.co_filename
|
| 124 | lineno = f.line_number()
|
| 125 | print(' File "%s", line %d, in %s' % (
|
| 126 | filename, lineno, f.f_code.co_name
|
| 127 | ))
|
| 128 | linecache.checkcache(filename)
|
| 129 | line = linecache.getline(filename, lineno, f.f_globals)
|
| 130 | if line:
|
| 131 | print(' ' + line.strip())
|
| 132 |
|
| 133 | def resume_frame(self, frame):
|
| 134 | frame.f_back = self.frame
|
| 135 | val = self.run_frame(frame)
|
| 136 | frame.f_back = None
|
| 137 | return val
|
| 138 |
|
| 139 | def run_code(self, code, f_globals=None, f_locals=None):
|
| 140 | frame = self.make_frame(code, f_globals=f_globals, f_locals=f_locals)
|
| 141 | val = self.run_frame(frame)
|
| 142 | # Check some invariants
|
| 143 | if self.frames: # pragma: no cover
|
| 144 | raise VirtualMachineError("Frames left over!")
|
| 145 | if self.frame and self.frame.stack: # pragma: no cover
|
| 146 | raise VirtualMachineError("Data left on stack! %r" % self.frame.stack)
|
| 147 |
|
| 148 | return val
|
| 149 |
|
| 150 | def unwind_block(self, block):
|
| 151 | if block.type == 'except-handler':
|
| 152 | offset = 3
|
| 153 | else:
|
| 154 | offset = 0
|
| 155 |
|
| 156 | while len(self.frame.stack) > block.level + offset:
|
| 157 | self.pop()
|
| 158 |
|
| 159 | if block.type == 'except-handler':
|
| 160 | tb, value, exctype = self.popn(3)
|
| 161 | self.last_exception = exctype, value, tb
|
| 162 |
|
| 163 | def parse_byte_and_args(self):
|
| 164 | """ Parse 1 - 3 bytes of bytecode into
|
| 165 | an instruction and optionally arguments."""
|
| 166 | f = self.frame
|
| 167 | opoffset = f.f_lasti
|
| 168 | byteCode = ord(f.f_code.co_code[opoffset])
|
| 169 | f.f_lasti += 1
|
| 170 | byteName = dis.opname[byteCode]
|
| 171 | arg = None
|
| 172 | arguments = []
|
| 173 | if byteCode >= dis.HAVE_ARGUMENT:
|
| 174 | arg = f.f_code.co_code[f.f_lasti:f.f_lasti+2]
|
| 175 | f.f_lasti += 2
|
| 176 | intArg = ord(arg[0]) + (ord(arg[1]) << 8)
|
| 177 | if byteCode in dis.hasconst:
|
| 178 | arg = f.f_code.co_consts[intArg]
|
| 179 | elif byteCode in dis.hasfree:
|
| 180 | if intArg < len(f.f_code.co_cellvars):
|
| 181 | arg = f.f_code.co_cellvars[intArg]
|
| 182 | else:
|
| 183 | var_idx = intArg - len(f.f_code.co_cellvars)
|
| 184 | arg = f.f_code.co_freevars[var_idx]
|
| 185 | elif byteCode in dis.hasname:
|
| 186 | arg = f.f_code.co_names[intArg]
|
| 187 | elif byteCode in dis.hasjrel:
|
| 188 | arg = f.f_lasti + intArg
|
| 189 | elif byteCode in dis.hasjabs:
|
| 190 | arg = intArg
|
| 191 | elif byteCode in dis.haslocal:
|
| 192 | arg = f.f_code.co_varnames[intArg]
|
| 193 | else:
|
| 194 | arg = intArg
|
| 195 | arguments = [arg]
|
| 196 |
|
| 197 | return byteName, arguments, opoffset
|
| 198 |
|
| 199 | def log(self, byteName, arguments, opoffset):
|
| 200 | """ Log arguments, block stack, and data stack for each opcode."""
|
| 201 | op = "%d: %s" % (opoffset, byteName)
|
| 202 | if arguments:
|
| 203 | op += " %r" % (arguments[0],)
|
| 204 | indent = " "*(len(self.frames)-1)
|
| 205 | stack_rep = repper(self.frame.stack)
|
| 206 | block_stack_rep = repper(self.frame.block_stack)
|
| 207 |
|
| 208 | log.info(" %sdata: %s" % (indent, stack_rep))
|
| 209 | log.info(" %sblks: %s" % (indent, block_stack_rep))
|
| 210 | log.info("%s%s" % (indent, op))
|
| 211 |
|
| 212 | def dispatch(self, byteName, arguments):
|
| 213 | """ Dispatch by bytename to the corresponding methods.
|
| 214 | Exceptions are caught and set on the virtual machine."""
|
| 215 | why = None
|
| 216 | try:
|
| 217 | if byteName.startswith('UNARY_'):
|
| 218 | self.unaryOperator(byteName[6:])
|
| 219 | elif byteName.startswith('BINARY_'):
|
| 220 | self.binaryOperator(byteName[7:])
|
| 221 | elif byteName.startswith('INPLACE_'):
|
| 222 | self.inplaceOperator(byteName[8:])
|
| 223 | elif 'SLICE+' in byteName:
|
| 224 | self.sliceOperator(byteName)
|
| 225 | else:
|
| 226 | # dispatch
|
| 227 | bytecode_fn = getattr(self, 'byte_%s' % byteName, None)
|
| 228 | if not bytecode_fn: # pragma: no cover
|
| 229 | raise VirtualMachineError(
|
| 230 | "unknown bytecode type: %s" % byteName
|
| 231 | )
|
| 232 | why = bytecode_fn(*arguments)
|
| 233 |
|
| 234 | except:
|
| 235 | # deal with exceptions encountered while executing the op.
|
| 236 | self.last_exception = sys.exc_info()[:2] + (None,)
|
| 237 | log.info("Caught exception during execution")
|
| 238 | why = 'exception'
|
| 239 |
|
| 240 | return why
|
| 241 |
|
| 242 | def manage_block_stack(self, why):
|
| 243 | """ Manage a frame's block stack.
|
| 244 | Manipulate the block stack and data stack for looping,
|
| 245 | exception handling, or returning."""
|
| 246 | assert why != 'yield'
|
| 247 |
|
| 248 | block = self.frame.block_stack[-1]
|
| 249 | if block.type == 'loop' and why == 'continue':
|
| 250 | self.jump(self.return_value)
|
| 251 | why = None
|
| 252 | return why
|
| 253 |
|
| 254 | self.pop_block()
|
| 255 | self.unwind_block(block)
|
| 256 |
|
| 257 | if block.type == 'loop' and why == 'break':
|
| 258 | why = None
|
| 259 | self.jump(block.handler)
|
| 260 | return why
|
| 261 |
|
| 262 | if PY2:
|
| 263 | if (
|
| 264 | block.type == 'finally' or
|
| 265 | (block.type == 'setup-except' and why == 'exception') or
|
| 266 | block.type == 'with'
|
| 267 | ):
|
| 268 | if why == 'exception':
|
| 269 | exctype, value, tb = self.last_exception
|
| 270 | self.push(tb, value, exctype)
|
| 271 | else:
|
| 272 | if why in ('return', 'continue'):
|
| 273 | self.push(self.return_value)
|
| 274 | self.push(why)
|
| 275 |
|
| 276 | why = None
|
| 277 | self.jump(block.handler)
|
| 278 | return why
|
| 279 |
|
| 280 | elif PY3:
|
| 281 | if (
|
| 282 | why == 'exception' and
|
| 283 | block.type in ['setup-except', 'finally']
|
| 284 | ):
|
| 285 | self.push_block('except-handler')
|
| 286 | exctype, value, tb = self.last_exception
|
| 287 | self.push(tb, value, exctype)
|
| 288 | # PyErr_Normalize_Exception goes here
|
| 289 | self.push(tb, value, exctype)
|
| 290 | why = None
|
| 291 | self.jump(block.handler)
|
| 292 | return why
|
| 293 |
|
| 294 | elif block.type == 'finally':
|
| 295 | if why in ('return', 'continue'):
|
| 296 | self.push(self.return_value)
|
| 297 | self.push(why)
|
| 298 |
|
| 299 | why = None
|
| 300 | self.jump(block.handler)
|
| 301 | return why
|
| 302 |
|
| 303 | return why
|
| 304 |
|
| 305 |
|
| 306 | def run_frame(self, frame):
|
| 307 | """Run a frame until it returns (somehow).
|
| 308 |
|
| 309 | Exceptions are raised, the return value is returned.
|
| 310 |
|
| 311 | """
|
| 312 | self.push_frame(frame)
|
| 313 | num_ticks = 0
|
| 314 | while True:
|
| 315 | num_ticks += 1
|
| 316 | byteName, arguments, opoffset = self.parse_byte_and_args()
|
| 317 | if log.isEnabledFor(logging.INFO):
|
| 318 | self.log(byteName, arguments, opoffset)
|
| 319 |
|
| 320 | # When unwinding the block stack, we need to keep track of why we
|
| 321 | # are doing it.
|
| 322 | why = self.dispatch(byteName, arguments)
|
| 323 | if why == 'exception':
|
| 324 | # TODO: ceval calls PyTraceBack_Here, not sure what that does.
|
| 325 | pass
|
| 326 |
|
| 327 | if why == 'reraise':
|
| 328 | why = 'exception'
|
| 329 |
|
| 330 | if why != 'yield':
|
| 331 | while why and frame.block_stack:
|
| 332 | # Deal with any block management we need to do.
|
| 333 | why = self.manage_block_stack(why)
|
| 334 |
|
| 335 | if why:
|
| 336 | break
|
| 337 |
|
| 338 | # TODO: handle generator exception state
|
| 339 |
|
| 340 | self.pop_frame()
|
| 341 |
|
| 342 | if why == 'exception':
|
| 343 | # Hm there is no third traceback part of the tuple?
|
| 344 | #print('GOT', self.last_exception)
|
| 345 | six.reraise(*self.last_exception)
|
| 346 | # How to raise with_traceback? Is that Python 3 only?
|
| 347 | #raise self.last_exception
|
| 348 |
|
| 349 | #print('num_ticks: %d' % num_ticks)
|
| 350 | return self.return_value
|
| 351 |
|
| 352 | ## Stack manipulation
|
| 353 |
|
| 354 | def byte_LOAD_CONST(self, const):
|
| 355 | self.push(const)
|
| 356 |
|
| 357 | def byte_POP_TOP(self):
|
| 358 | self.pop()
|
| 359 |
|
| 360 | def byte_DUP_TOP(self):
|
| 361 | self.push(self.top())
|
| 362 |
|
| 363 | def byte_DUP_TOPX(self, count):
|
| 364 | items = self.popn(count)
|
| 365 | for i in [1, 2]:
|
| 366 | self.push(*items)
|
| 367 |
|
| 368 | def byte_DUP_TOP_TWO(self):
|
| 369 | # Py3 only
|
| 370 | a, b = self.popn(2)
|
| 371 | self.push(a, b, a, b)
|
| 372 |
|
| 373 | def byte_ROT_TWO(self):
|
| 374 | a, b = self.popn(2)
|
| 375 | self.push(b, a)
|
| 376 |
|
| 377 | def byte_ROT_THREE(self):
|
| 378 | a, b, c = self.popn(3)
|
| 379 | self.push(c, a, b)
|
| 380 |
|
| 381 | def byte_ROT_FOUR(self):
|
| 382 | a, b, c, d = self.popn(4)
|
| 383 | self.push(d, a, b, c)
|
| 384 |
|
| 385 | ## Names
|
| 386 |
|
| 387 | def byte_LOAD_NAME(self, name):
|
| 388 | frame = self.frame
|
| 389 | if name in frame.f_locals:
|
| 390 | val = frame.f_locals[name]
|
| 391 | elif name in frame.f_globals:
|
| 392 | val = frame.f_globals[name]
|
| 393 | elif name in frame.f_builtins:
|
| 394 | val = frame.f_builtins[name]
|
| 395 | else:
|
| 396 | raise NameError("name '%s' is not defined" % name)
|
| 397 | self.push(val)
|
| 398 |
|
| 399 | def byte_STORE_NAME(self, name):
|
| 400 | self.frame.f_locals[name] = self.pop()
|
| 401 |
|
| 402 | def byte_DELETE_NAME(self, name):
|
| 403 | del self.frame.f_locals[name]
|
| 404 |
|
| 405 | def byte_LOAD_FAST(self, name):
|
| 406 | if name in self.frame.f_locals:
|
| 407 | val = self.frame.f_locals[name]
|
| 408 | else:
|
| 409 | raise UnboundLocalError(
|
| 410 | "local variable '%s' referenced before assignment" % name
|
| 411 | )
|
| 412 | self.push(val)
|
| 413 |
|
| 414 | def byte_STORE_FAST(self, name):
|
| 415 | self.frame.f_locals[name] = self.pop()
|
| 416 |
|
| 417 | def byte_DELETE_FAST(self, name):
|
| 418 | del self.frame.f_locals[name]
|
| 419 |
|
| 420 | def byte_LOAD_GLOBAL(self, name):
|
| 421 | f = self.frame
|
| 422 | if name in f.f_globals:
|
| 423 | val = f.f_globals[name]
|
| 424 | elif name in f.f_builtins:
|
| 425 | val = f.f_builtins[name]
|
| 426 | else:
|
| 427 | raise NameError("global name '%s' is not defined" % name)
|
| 428 | self.push(val)
|
| 429 |
|
| 430 | def byte_STORE_GLOBAL(self, name):
|
| 431 | f = self.frame
|
| 432 | f.f_globals[name] = self.pop()
|
| 433 |
|
| 434 | def byte_LOAD_DEREF(self, name):
|
| 435 | self.push(self.frame.cells[name].get())
|
| 436 |
|
| 437 | def byte_STORE_DEREF(self, name):
|
| 438 | self.frame.cells[name].set(self.pop())
|
| 439 |
|
| 440 | def byte_LOAD_LOCALS(self):
|
| 441 | self.push(self.frame.f_locals)
|
| 442 |
|
| 443 | ## Operators
|
| 444 |
|
| 445 | UNARY_OPERATORS = {
|
| 446 | 'POSITIVE': operator.pos,
|
| 447 | 'NEGATIVE': operator.neg,
|
| 448 | 'NOT': operator.not_,
|
| 449 | 'CONVERT': repr,
|
| 450 | 'INVERT': operator.invert,
|
| 451 | }
|
| 452 |
|
| 453 | def unaryOperator(self, op):
|
| 454 | x = self.pop()
|
| 455 | self.push(self.UNARY_OPERATORS[op](x))
|
| 456 |
|
| 457 | BINARY_OPERATORS = {
|
| 458 | 'POWER': pow,
|
| 459 | 'MULTIPLY': operator.mul,
|
| 460 | 'DIVIDE': getattr(operator, 'div', lambda x, y: None),
|
| 461 | 'FLOOR_DIVIDE': operator.floordiv,
|
| 462 | 'TRUE_DIVIDE': operator.truediv,
|
| 463 | 'MODULO': operator.mod,
|
| 464 | 'ADD': operator.add,
|
| 465 | 'SUBTRACT': operator.sub,
|
| 466 | 'SUBSCR': operator.getitem,
|
| 467 | 'LSHIFT': operator.lshift,
|
| 468 | 'RSHIFT': operator.rshift,
|
| 469 | 'AND': operator.and_,
|
| 470 | 'XOR': operator.xor,
|
| 471 | 'OR': operator.or_,
|
| 472 | }
|
| 473 |
|
| 474 | def binaryOperator(self, op):
|
| 475 | x, y = self.popn(2)
|
| 476 | self.push(self.BINARY_OPERATORS[op](x, y))
|
| 477 |
|
| 478 | def inplaceOperator(self, op):
|
| 479 | x, y = self.popn(2)
|
| 480 | if op == 'POWER':
|
| 481 | x **= y
|
| 482 | elif op == 'MULTIPLY':
|
| 483 | x *= y
|
| 484 | elif op in ['DIVIDE', 'FLOOR_DIVIDE']:
|
| 485 | x //= y
|
| 486 | elif op == 'TRUE_DIVIDE':
|
| 487 | x /= y
|
| 488 | elif op == 'MODULO':
|
| 489 | x %= y
|
| 490 | elif op == 'ADD':
|
| 491 | x += y
|
| 492 | elif op == 'SUBTRACT':
|
| 493 | x -= y
|
| 494 | elif op == 'LSHIFT':
|
| 495 | x <<= y
|
| 496 | elif op == 'RSHIFT':
|
| 497 | x >>= y
|
| 498 | elif op == 'AND':
|
| 499 | x &= y
|
| 500 | elif op == 'XOR':
|
| 501 | x ^= y
|
| 502 | elif op == 'OR':
|
| 503 | x |= y
|
| 504 | else: # pragma: no cover
|
| 505 | raise VirtualMachineError("Unknown in-place operator: %r" % op)
|
| 506 | self.push(x)
|
| 507 |
|
| 508 | def sliceOperator(self, op):
|
| 509 | start = 0
|
| 510 | end = None # we will take this to mean end
|
| 511 | op, count = op[:-2], int(op[-1])
|
| 512 | if count == 1:
|
| 513 | start = self.pop()
|
| 514 | elif count == 2:
|
| 515 | end = self.pop()
|
| 516 | elif count == 3:
|
| 517 | end = self.pop()
|
| 518 | start = self.pop()
|
| 519 | l = self.pop()
|
| 520 | if end is None:
|
| 521 | end = len(l)
|
| 522 | if op.startswith('STORE_'):
|
| 523 | l[start:end] = self.pop()
|
| 524 | elif op.startswith('DELETE_'):
|
| 525 | del l[start:end]
|
| 526 | else:
|
| 527 | self.push(l[start:end])
|
| 528 |
|
| 529 | COMPARE_OPERATORS = [
|
| 530 | operator.lt,
|
| 531 | operator.le,
|
| 532 | operator.eq,
|
| 533 | operator.ne,
|
| 534 | operator.gt,
|
| 535 | operator.ge,
|
| 536 | lambda x, y: x in y,
|
| 537 | lambda x, y: x not in y,
|
| 538 | lambda x, y: x is y,
|
| 539 | lambda x, y: x is not y,
|
| 540 | lambda x, y: issubclass(x, Exception) and issubclass(x, y),
|
| 541 | ]
|
| 542 |
|
| 543 | def byte_COMPARE_OP(self, opnum):
|
| 544 | x, y = self.popn(2)
|
| 545 | self.push(self.COMPARE_OPERATORS[opnum](x, y))
|
| 546 |
|
| 547 | ## Attributes and indexing
|
| 548 |
|
| 549 | def byte_LOAD_ATTR(self, attr):
|
| 550 | obj = self.pop()
|
| 551 | val = getattr(obj, attr)
|
| 552 | self.push(val)
|
| 553 |
|
| 554 | def byte_STORE_ATTR(self, name):
|
| 555 | val, obj = self.popn(2)
|
| 556 | setattr(obj, name, val)
|
| 557 |
|
| 558 | def byte_DELETE_ATTR(self, name):
|
| 559 | obj = self.pop()
|
| 560 | delattr(obj, name)
|
| 561 |
|
| 562 | def byte_STORE_SUBSCR(self):
|
| 563 | val, obj, subscr = self.popn(3)
|
| 564 | obj[subscr] = val
|
| 565 |
|
| 566 | def byte_DELETE_SUBSCR(self):
|
| 567 | obj, subscr = self.popn(2)
|
| 568 | del obj[subscr]
|
| 569 |
|
| 570 | ## Building
|
| 571 |
|
| 572 | def byte_BUILD_TUPLE(self, count):
|
| 573 | elts = self.popn(count)
|
| 574 | self.push(tuple(elts))
|
| 575 |
|
| 576 | def byte_BUILD_LIST(self, count):
|
| 577 | elts = self.popn(count)
|
| 578 | self.push(elts)
|
| 579 |
|
| 580 | def byte_BUILD_SET(self, count):
|
| 581 | # TODO: Not documented in Py2 docs.
|
| 582 | elts = self.popn(count)
|
| 583 | self.push(set(elts))
|
| 584 |
|
| 585 | def byte_BUILD_MAP(self, size):
|
| 586 | # size is ignored.
|
| 587 | self.push({})
|
| 588 |
|
| 589 | def byte_STORE_MAP(self):
|
| 590 | the_map, val, key = self.popn(3)
|
| 591 | the_map[key] = val
|
| 592 | self.push(the_map)
|
| 593 |
|
| 594 | def byte_UNPACK_SEQUENCE(self, count):
|
| 595 | seq = self.pop()
|
| 596 | for x in reversed(seq):
|
| 597 | self.push(x)
|
| 598 |
|
| 599 | def byte_BUILD_SLICE(self, count):
|
| 600 | if count == 2:
|
| 601 | x, y = self.popn(2)
|
| 602 | self.push(slice(x, y))
|
| 603 | elif count == 3:
|
| 604 | x, y, z = self.popn(3)
|
| 605 | self.push(slice(x, y, z))
|
| 606 | else: # pragma: no cover
|
| 607 | raise VirtualMachineError("Strange BUILD_SLICE count: %r" % count)
|
| 608 |
|
| 609 | def byte_LIST_APPEND(self, count):
|
| 610 | val = self.pop()
|
| 611 | the_list = self.peek(count)
|
| 612 | the_list.append(val)
|
| 613 |
|
| 614 | def byte_SET_ADD(self, count):
|
| 615 | val = self.pop()
|
| 616 | the_set = self.peek(count)
|
| 617 | the_set.add(val)
|
| 618 |
|
| 619 | def byte_MAP_ADD(self, count):
|
| 620 | val, key = self.popn(2)
|
| 621 | the_map = self.peek(count)
|
| 622 | the_map[key] = val
|
| 623 |
|
| 624 | ## Printing
|
| 625 |
|
| 626 | if 0: # Only used in the interactive interpreter, not in modules.
|
| 627 | def byte_PRINT_EXPR(self):
|
| 628 | print(self.pop())
|
| 629 |
|
| 630 | def byte_PRINT_ITEM(self):
|
| 631 | item = self.pop()
|
| 632 | self.print_item(item)
|
| 633 |
|
| 634 | def byte_PRINT_ITEM_TO(self):
|
| 635 | to = self.pop()
|
| 636 | item = self.pop()
|
| 637 | self.print_item(item, to)
|
| 638 |
|
| 639 | def byte_PRINT_NEWLINE(self):
|
| 640 | self.print_newline()
|
| 641 |
|
| 642 | def byte_PRINT_NEWLINE_TO(self):
|
| 643 | to = self.pop()
|
| 644 | self.print_newline(to)
|
| 645 |
|
| 646 | def print_item(self, item, to=None):
|
| 647 | if to is None:
|
| 648 | to = sys.stdout
|
| 649 | if to.softspace:
|
| 650 | print(" ", end="", file=to)
|
| 651 | to.softspace = 0
|
| 652 | print(item, end="", file=to)
|
| 653 | if isinstance(item, str):
|
| 654 | if (not item) or (not item[-1].isspace()) or (item[-1] == " "):
|
| 655 | to.softspace = 1
|
| 656 | else:
|
| 657 | to.softspace = 1
|
| 658 |
|
| 659 | def print_newline(self, to=None):
|
| 660 | if to is None:
|
| 661 | to = sys.stdout
|
| 662 | print("", file=to)
|
| 663 | to.softspace = 0
|
| 664 |
|
| 665 | ## Jumps
|
| 666 |
|
| 667 | def byte_JUMP_FORWARD(self, jump):
|
| 668 | self.jump(jump)
|
| 669 |
|
| 670 | def byte_JUMP_ABSOLUTE(self, jump):
|
| 671 | self.jump(jump)
|
| 672 |
|
| 673 | if 0: # Not in py2.7
|
| 674 | def byte_JUMP_IF_TRUE(self, jump):
|
| 675 | val = self.top()
|
| 676 | if val:
|
| 677 | self.jump(jump)
|
| 678 |
|
| 679 | def byte_JUMP_IF_FALSE(self, jump):
|
| 680 | val = self.top()
|
| 681 | if not val:
|
| 682 | self.jump(jump)
|
| 683 |
|
| 684 | def byte_POP_JUMP_IF_TRUE(self, jump):
|
| 685 | val = self.pop()
|
| 686 | if val:
|
| 687 | self.jump(jump)
|
| 688 |
|
| 689 | def byte_POP_JUMP_IF_FALSE(self, jump):
|
| 690 | val = self.pop()
|
| 691 | if not val:
|
| 692 | self.jump(jump)
|
| 693 |
|
| 694 | def byte_JUMP_IF_TRUE_OR_POP(self, jump):
|
| 695 | val = self.top()
|
| 696 | if val:
|
| 697 | self.jump(jump)
|
| 698 | else:
|
| 699 | self.pop()
|
| 700 |
|
| 701 | def byte_JUMP_IF_FALSE_OR_POP(self, jump):
|
| 702 | val = self.top()
|
| 703 | if not val:
|
| 704 | self.jump(jump)
|
| 705 | else:
|
| 706 | self.pop()
|
| 707 |
|
| 708 | ## Blocks
|
| 709 |
|
| 710 | def byte_SETUP_LOOP(self, dest):
|
| 711 | self.push_block('loop', dest)
|
| 712 |
|
| 713 | def byte_GET_ITER(self):
|
| 714 | self.push(iter(self.pop()))
|
| 715 |
|
| 716 | def byte_FOR_ITER(self, jump):
|
| 717 | iterobj = self.top()
|
| 718 | try:
|
| 719 | v = next(iterobj)
|
| 720 | self.push(v)
|
| 721 | except StopIteration:
|
| 722 | self.pop()
|
| 723 | self.jump(jump)
|
| 724 |
|
| 725 | def byte_BREAK_LOOP(self):
|
| 726 | return 'break'
|
| 727 |
|
| 728 | def byte_CONTINUE_LOOP(self, dest):
|
| 729 | # This is a trick with the return value.
|
| 730 | # While unrolling blocks, continue and return both have to preserve
|
| 731 | # state as the finally blocks are executed. For continue, it's
|
| 732 | # where to jump to, for return, it's the value to return. It gets
|
| 733 | # pushed on the stack for both, so continue puts the jump destination
|
| 734 | # into return_value.
|
| 735 | self.return_value = dest
|
| 736 | return 'continue'
|
| 737 |
|
| 738 | def byte_SETUP_EXCEPT(self, dest):
|
| 739 | self.push_block('setup-except', dest)
|
| 740 |
|
| 741 | def byte_SETUP_FINALLY(self, dest):
|
| 742 | self.push_block('finally', dest)
|
| 743 |
|
| 744 | def byte_END_FINALLY(self):
|
| 745 | v = self.pop()
|
| 746 | if isinstance(v, str):
|
| 747 | why = v
|
| 748 | if why in ('return', 'continue'):
|
| 749 | self.return_value = self.pop()
|
| 750 | if why == 'silenced': # PY3
|
| 751 | block = self.pop_block()
|
| 752 | assert block.type == 'except-handler'
|
| 753 | self.unwind_block(block)
|
| 754 | why = None
|
| 755 | elif v is None:
|
| 756 | why = None
|
| 757 | elif issubclass(v, BaseException):
|
| 758 | exctype = v
|
| 759 | val = self.pop()
|
| 760 | tb = self.pop()
|
| 761 | self.last_exception = (exctype, val, tb)
|
| 762 | why = 'reraise'
|
| 763 | else: # pragma: no cover
|
| 764 | raise VirtualMachineError("Confused END_FINALLY")
|
| 765 | return why
|
| 766 |
|
| 767 | def byte_POP_BLOCK(self):
|
| 768 | self.pop_block()
|
| 769 |
|
| 770 | if PY2:
|
| 771 | def byte_RAISE_VARARGS(self, argc):
|
| 772 | # NOTE: the dis docs are completely wrong about the order of the
|
| 773 | # operands on the stack!
|
| 774 | exctype = val = tb = None
|
| 775 | if argc == 0:
|
| 776 | exctype, val, tb = self.last_exception
|
| 777 | elif argc == 1:
|
| 778 | exctype = self.pop()
|
| 779 | elif argc == 2:
|
| 780 | val = self.pop()
|
| 781 | exctype = self.pop()
|
| 782 | elif argc == 3:
|
| 783 | tb = self.pop()
|
| 784 | val = self.pop()
|
| 785 | exctype = self.pop()
|
| 786 |
|
| 787 | # There are a number of forms of "raise", normalize them somewhat.
|
| 788 | if isinstance(exctype, BaseException):
|
| 789 | val = exctype
|
| 790 | exctype = type(val)
|
| 791 |
|
| 792 | self.last_exception = (exctype, val, tb)
|
| 793 |
|
| 794 | if tb:
|
| 795 | return 'reraise'
|
| 796 | else:
|
| 797 | return 'exception'
|
| 798 |
|
| 799 | elif PY3:
|
| 800 | def byte_RAISE_VARARGS(self, argc):
|
| 801 | cause = exc = None
|
| 802 | if argc == 2:
|
| 803 | cause = self.pop()
|
| 804 | exc = self.pop()
|
| 805 | elif argc == 1:
|
| 806 | exc = self.pop()
|
| 807 | return self.do_raise(exc, cause)
|
| 808 |
|
| 809 | def do_raise(self, exc, cause):
|
| 810 | if exc is None: # reraise
|
| 811 | exc_type, val, tb = self.last_exception
|
| 812 | if exc_type is None:
|
| 813 | return 'exception' # error
|
| 814 | else:
|
| 815 | return 'reraise'
|
| 816 |
|
| 817 | elif type(exc) == type:
|
| 818 | # As in `raise ValueError`
|
| 819 | exc_type = exc
|
| 820 | val = exc() # Make an instance.
|
| 821 | elif isinstance(exc, BaseException):
|
| 822 | # As in `raise ValueError('foo')`
|
| 823 | exc_type = type(exc)
|
| 824 | val = exc
|
| 825 | else:
|
| 826 | return 'exception' # error
|
| 827 |
|
| 828 | # If you reach this point, you're guaranteed that
|
| 829 | # val is a valid exception instance and exc_type is its class.
|
| 830 | # Now do a similar thing for the cause, if present.
|
| 831 | if cause:
|
| 832 | if type(cause) == type:
|
| 833 | cause = cause()
|
| 834 | elif not isinstance(cause, BaseException):
|
| 835 | return 'exception' # error
|
| 836 |
|
| 837 | val.__cause__ = cause
|
| 838 |
|
| 839 | self.last_exception = exc_type, val, val.__traceback__
|
| 840 | return 'exception'
|
| 841 |
|
| 842 | def byte_POP_EXCEPT(self):
|
| 843 | block = self.pop_block()
|
| 844 | if block.type != 'except-handler':
|
| 845 | raise Exception("popped block is not an except handler")
|
| 846 | self.unwind_block(block)
|
| 847 |
|
| 848 | def byte_SETUP_WITH(self, dest):
|
| 849 | ctxmgr = self.pop()
|
| 850 | self.push(ctxmgr.__exit__)
|
| 851 | ctxmgr_obj = ctxmgr.__enter__()
|
| 852 | if PY2:
|
| 853 | self.push_block('with', dest)
|
| 854 | elif PY3:
|
| 855 | self.push_block('finally', dest)
|
| 856 | self.push(ctxmgr_obj)
|
| 857 |
|
| 858 | def byte_WITH_CLEANUP(self):
|
| 859 | # The code here does some weird stack manipulation: the exit function
|
| 860 | # is buried in the stack, and where depends on what's on top of it.
|
| 861 | # Pull out the exit function, and leave the rest in place.
|
| 862 | v = w = None
|
| 863 | u = self.top()
|
| 864 | if u is None:
|
| 865 | exit_func = self.pop(1)
|
| 866 | elif isinstance(u, str):
|
| 867 | if u in ('return', 'continue'):
|
| 868 | exit_func = self.pop(2)
|
| 869 | else:
|
| 870 | exit_func = self.pop(1)
|
| 871 | u = None
|
| 872 | elif issubclass(u, BaseException):
|
| 873 | if PY2:
|
| 874 | w, v, u = self.popn(3)
|
| 875 | exit_func = self.pop()
|
| 876 | self.push(w, v, u)
|
| 877 | elif PY3:
|
| 878 | w, v, u = self.popn(3)
|
| 879 | tp, exc, tb = self.popn(3)
|
| 880 | exit_func = self.pop()
|
| 881 | self.push(tp, exc, tb)
|
| 882 | self.push(None)
|
| 883 | self.push(w, v, u)
|
| 884 | block = self.pop_block()
|
| 885 | assert block.type == 'except-handler'
|
| 886 | self.push_block(block.type, block.handler, block.level-1)
|
| 887 | else: # pragma: no cover
|
| 888 | raise VirtualMachineError("Confused WITH_CLEANUP")
|
| 889 | exit_ret = exit_func(u, v, w)
|
| 890 | err = (u is not None) and bool(exit_ret)
|
| 891 | if err:
|
| 892 | # An error occurred, and was suppressed
|
| 893 | if PY2:
|
| 894 | self.popn(3)
|
| 895 | self.push(None)
|
| 896 | elif PY3:
|
| 897 | self.push('silenced')
|
| 898 |
|
| 899 | ## Functions
|
| 900 |
|
| 901 | def byte_MAKE_FUNCTION(self, argc):
|
| 902 | if PY3:
|
| 903 | name = self.pop()
|
| 904 | else:
|
| 905 | name = None
|
| 906 | code = self.pop()
|
| 907 | defaults = self.popn(argc)
|
| 908 | globs = self.frame.f_globals
|
| 909 | fn = Function(name, code, globs, defaults, None, self)
|
| 910 | self.push(fn)
|
| 911 |
|
| 912 | def byte_LOAD_CLOSURE(self, name):
|
| 913 | self.push(self.frame.cells[name])
|
| 914 |
|
| 915 | def byte_MAKE_CLOSURE(self, argc):
|
| 916 | if PY3:
|
| 917 | # TODO: the py3 docs don't mention this change.
|
| 918 | name = self.pop()
|
| 919 | else:
|
| 920 | name = None
|
| 921 | closure, code = self.popn(2)
|
| 922 | defaults = self.popn(argc)
|
| 923 | globs = self.frame.f_globals
|
| 924 | fn = Function(name, code, globs, defaults, closure, self)
|
| 925 | self.push(fn)
|
| 926 |
|
| 927 | def byte_CALL_FUNCTION(self, arg):
|
| 928 | return self.call_function(arg, [], {})
|
| 929 |
|
| 930 | def byte_CALL_FUNCTION_VAR(self, arg):
|
| 931 | args = self.pop()
|
| 932 | return self.call_function(arg, args, {})
|
| 933 |
|
| 934 | def byte_CALL_FUNCTION_KW(self, arg):
|
| 935 | kwargs = self.pop()
|
| 936 | return self.call_function(arg, [], kwargs)
|
| 937 |
|
| 938 | def byte_CALL_FUNCTION_VAR_KW(self, arg):
|
| 939 | args, kwargs = self.popn(2)
|
| 940 | return self.call_function(arg, args, kwargs)
|
| 941 |
|
| 942 | def call_function(self, arg, args, kwargs):
|
| 943 | lenKw, lenPos = divmod(arg, 256)
|
| 944 | namedargs = {}
|
| 945 | for i in range(lenKw):
|
| 946 | key, val = self.popn(2)
|
| 947 | namedargs[key] = val
|
| 948 | namedargs.update(kwargs)
|
| 949 | posargs = self.popn(lenPos)
|
| 950 | posargs.extend(args)
|
| 951 |
|
| 952 | func = self.pop()
|
| 953 | frame = self.frame
|
| 954 | if hasattr(func, 'im_func'):
|
| 955 | # Methods get self as an implicit first parameter.
|
| 956 | if func.im_self:
|
| 957 | posargs.insert(0, func.im_self)
|
| 958 | # The first parameter must be the correct type.
|
| 959 | if not isinstance(posargs[0], func.im_class):
|
| 960 | raise TypeError(
|
| 961 | 'unbound method %s() must be called with %s instance '
|
| 962 | 'as first argument (got %s instance instead)' % (
|
| 963 | func.im_func.func_name,
|
| 964 | func.im_class.__name__,
|
| 965 | type(posargs[0]).__name__,
|
| 966 | )
|
| 967 | )
|
| 968 | func = func.im_func
|
| 969 |
|
| 970 | # BUG FIX: The callable must be a pyobj.Function, not a native Python
|
| 971 | # function (types.FunctionType). The latter will be executed using the
|
| 972 | # HOST CPython interpreter rather than the byterun interpreter.
|
| 973 |
|
| 974 | # Cases:
|
| 975 | # 1. builtin functions like int(). We want to use the host here.
|
| 976 | # 2. User-defined functions from this module. These are created with
|
| 977 | # MAKE_FUNCTION, which properly turns them into pyobj.Function.
|
| 978 | # 3. User-defined function from another module. These are created with
|
| 979 | # __import__, which yields a native function.
|
| 980 |
|
| 981 | if isinstance(func, types.FunctionType):
|
| 982 | defaults = func.func_defaults or ()
|
| 983 | byterun_func = Function(
|
| 984 | func.func_name, func.func_code, func.func_globals,
|
| 985 | defaults, func.func_closure, self)
|
| 986 | else:
|
| 987 | byterun_func = func
|
| 988 |
|
| 989 | retval = byterun_func(*posargs, **namedargs)
|
| 990 | self.push(retval)
|
| 991 |
|
| 992 | def byte_RETURN_VALUE(self):
|
| 993 | self.return_value = self.pop()
|
| 994 | if self.frame.generator:
|
| 995 | self.frame.generator.finished = True
|
| 996 | return "return"
|
| 997 |
|
| 998 | def byte_YIELD_VALUE(self):
|
| 999 | self.return_value = self.pop()
|
| 1000 | return "yield"
|
| 1001 |
|
| 1002 | def byte_YIELD_FROM(self):
|
| 1003 | u = self.pop()
|
| 1004 | x = self.top()
|
| 1005 |
|
| 1006 | try:
|
| 1007 | if not isinstance(x, Generator) or u is None:
|
| 1008 | # Call next on iterators.
|
| 1009 | retval = next(x)
|
| 1010 | else:
|
| 1011 | retval = x.send(u)
|
| 1012 | self.return_value = retval
|
| 1013 | except StopIteration as e:
|
| 1014 | self.pop()
|
| 1015 | self.push(e.value)
|
| 1016 | else:
|
| 1017 | # YIELD_FROM decrements f_lasti, so that it will be called
|
| 1018 | # repeatedly until a StopIteration is raised.
|
| 1019 | self.jump(self.frame.f_lasti - 1)
|
| 1020 | # Returning "yield" prevents the block stack cleanup code
|
| 1021 | # from executing, suspending the frame in its current state.
|
| 1022 | return "yield"
|
| 1023 |
|
| 1024 | ## Importing
|
| 1025 |
|
| 1026 | def byte_IMPORT_NAME(self, name):
|
| 1027 | level, fromlist = self.popn(2)
|
| 1028 | frame = self.frame
|
| 1029 | mod = __import__(name, frame.f_globals, frame.f_locals, fromlist, level)
|
| 1030 | #print('-- IMPORTED %s -> %s' % (name, mod))
|
| 1031 | self.push(mod)
|
| 1032 |
|
| 1033 | def byte_IMPORT_STAR(self):
|
| 1034 | # TODO: this doesn't use __all__ properly.
|
| 1035 | mod = self.pop()
|
| 1036 | for attr in dir(mod):
|
| 1037 | if attr[0] != '_':
|
| 1038 | self.frame.f_locals[attr] = getattr(mod, attr)
|
| 1039 |
|
| 1040 | def byte_IMPORT_FROM(self, name):
|
| 1041 | mod = self.top()
|
| 1042 | self.push(getattr(mod, name))
|
| 1043 |
|
| 1044 | ## And the rest...
|
| 1045 |
|
| 1046 | def byte_EXEC_STMT(self):
|
| 1047 | stmt, globs, locs = self.popn(3)
|
| 1048 | six.exec_(stmt, globs, locs)
|
| 1049 |
|
| 1050 | if PY2:
|
| 1051 | def byte_BUILD_CLASS(self):
|
| 1052 | name, bases, methods = self.popn(3)
|
| 1053 | self.push(type(name, bases, methods))
|
| 1054 |
|
| 1055 |
|
| 1056 | elif PY3:
|
| 1057 | def byte_LOAD_BUILD_CLASS(self):
|
| 1058 | # New in py3
|
| 1059 | self.push(__build_class__)
|
| 1060 |
|
| 1061 | def byte_STORE_LOCALS(self):
|
| 1062 | self.frame.f_locals = self.pop()
|
| 1063 |
|
| 1064 | if 0: # Not in py2.7
|
| 1065 | def byte_SET_LINENO(self, lineno):
|
| 1066 | self.frame.f_lineno = lineno
|