| 1 | """vm.py: Library for executing shell."""
|
| 2 | from __future__ import print_function
|
| 3 |
|
| 4 | from _devbuild.gen.id_kind_asdl import Id, Id_t, Id_str
|
| 5 | from _devbuild.gen.runtime_asdl import (CommandStatus, StatusArray, flow_e,
|
| 6 | flow_t)
|
| 7 | from _devbuild.gen.syntax_asdl import Token, loc, loc_t
|
| 8 | from _devbuild.gen.value_asdl import value, value_e, value_t, Obj
|
| 9 | from core import dev
|
| 10 | from core import error
|
| 11 | from core.error import e_die
|
| 12 | from core import pyos
|
| 13 | from core import pyutil
|
| 14 | from display import ui
|
| 15 | from mycpp.mylib import log, tagswitch
|
| 16 |
|
| 17 | from typing import List, Dict, Tuple, Optional, Any, cast, TYPE_CHECKING
|
| 18 | if TYPE_CHECKING:
|
| 19 | from _devbuild.gen.runtime_asdl import cmd_value, RedirValue
|
| 20 | from _devbuild.gen.syntax_asdl import (command, command_t, CommandSub)
|
| 21 | from builtin import hay_ysh
|
| 22 | from core import optview
|
| 23 | from core import state
|
| 24 | from frontend import typed_args
|
| 25 | from osh import sh_expr_eval
|
| 26 | from osh.sh_expr_eval import ArithEvaluator
|
| 27 | from osh.sh_expr_eval import BoolEvaluator
|
| 28 | from osh import word_eval
|
| 29 | from osh import cmd_eval
|
| 30 | from osh import prompt
|
| 31 | from ysh import expr_eval
|
| 32 |
|
| 33 | _ = log
|
| 34 |
|
| 35 |
|
| 36 | class ControlFlow(Exception):
|
| 37 | """Internal exception for control flow.
|
| 38 |
|
| 39 | Used by CommandEvaluator and 'source' builtin
|
| 40 |
|
| 41 | break and continue are caught by loops, return is caught by functions.
|
| 42 | """
|
| 43 | pass
|
| 44 |
|
| 45 |
|
| 46 | class IntControlFlow(Exception):
|
| 47 |
|
| 48 | def __init__(self, keyword_id, keyword_str, keyword_loc, arg):
|
| 49 | # type: (Id_t, str, loc_t, int) -> None
|
| 50 | """
|
| 51 | Args:
|
| 52 | token: the keyword token
|
| 53 | arg: exit code to 'return', or number of levels to break/continue
|
| 54 | """
|
| 55 | self.keyword_id = keyword_id
|
| 56 | self.keyword_str = keyword_str
|
| 57 | self.keyword_loc = keyword_loc
|
| 58 | self.arg = arg
|
| 59 |
|
| 60 | def Keyword(self):
|
| 61 | # type: () -> str
|
| 62 | return self.keyword_str
|
| 63 |
|
| 64 | def Location(self):
|
| 65 | # type: () -> loc_t
|
| 66 | return self.keyword_loc
|
| 67 |
|
| 68 | def IsReturn(self):
|
| 69 | # type: () -> bool
|
| 70 | return self.keyword_id == Id.ControlFlow_Return
|
| 71 |
|
| 72 | def IsBreak(self):
|
| 73 | # type: () -> bool
|
| 74 | return self.keyword_id == Id.ControlFlow_Break
|
| 75 |
|
| 76 | def IsContinue(self):
|
| 77 | # type: () -> bool
|
| 78 | return self.keyword_id == Id.ControlFlow_Continue
|
| 79 |
|
| 80 | def StatusCode(self):
|
| 81 | # type: () -> int
|
| 82 | assert self.IsReturn()
|
| 83 | # All shells except dash do this truncation.
|
| 84 | # turn 257 into 1, and -1 into 255.
|
| 85 | return self.arg & 0xff
|
| 86 |
|
| 87 | def HandleLoop(self):
|
| 88 | # type: () -> flow_t
|
| 89 | """Mutates this exception and returns what the caller should do."""
|
| 90 |
|
| 91 | if self.IsBreak():
|
| 92 | self.arg -= 1
|
| 93 | if self.arg == 0:
|
| 94 | return flow_e.Break # caller should break out of loop
|
| 95 |
|
| 96 | elif self.IsContinue():
|
| 97 | self.arg -= 1
|
| 98 | if self.arg == 0:
|
| 99 | return flow_e.Nothing # do nothing to continue
|
| 100 |
|
| 101 | # return / break 2 / continue 2 need to pop up more
|
| 102 | return flow_e.Raise
|
| 103 |
|
| 104 | def __repr__(self):
|
| 105 | # type: () -> str
|
| 106 | return '<IntControlFlow %s %s>' % (Id_str(self.keyword_id), self.arg)
|
| 107 |
|
| 108 |
|
| 109 | class ValueControlFlow(Exception):
|
| 110 |
|
| 111 | def __init__(self, token, value):
|
| 112 | # type: (Token, value_t) -> None
|
| 113 | """
|
| 114 | Args:
|
| 115 | token: the keyword token
|
| 116 | value: value_t to 'return' from a function
|
| 117 | """
|
| 118 | self.token = token
|
| 119 | self.value = value
|
| 120 |
|
| 121 | def __repr__(self):
|
| 122 | # type: () -> str
|
| 123 | return '<ValueControlFlow %s %s>' % (self.token, self.value)
|
| 124 |
|
| 125 |
|
| 126 | def InitUnsafeArith(mem, word_ev, unsafe_arith):
|
| 127 | # type: (state.Mem, word_eval.NormalWordEvaluator, sh_expr_eval.UnsafeArith) -> None
|
| 128 | """Wire up circular dependencies for UnsafeArith."""
|
| 129 | mem.unsafe_arith = unsafe_arith # for 'declare -n' nameref expansion of a[i]
|
| 130 | word_ev.unsafe_arith = unsafe_arith # for ${!ref} expansion of a[i]
|
| 131 |
|
| 132 |
|
| 133 | def InitCircularDeps(
|
| 134 | arith_ev, # type: ArithEvaluator
|
| 135 | bool_ev, # type: BoolEvaluator
|
| 136 | expr_ev, # type: expr_eval.ExprEvaluator
|
| 137 | word_ev, # type: word_eval.NormalWordEvaluator
|
| 138 | cmd_ev, # type: cmd_eval.CommandEvaluator
|
| 139 | shell_ex, # type: _Executor
|
| 140 | pure_ex, # type: _Executor
|
| 141 | prompt_ev, # type: prompt.Evaluator
|
| 142 | global_io, # type: Obj
|
| 143 | tracer, # type: dev.Tracer
|
| 144 | ):
|
| 145 | # type: (...) -> None
|
| 146 | """Wire up mutually recursive evaluators and runtime objects."""
|
| 147 | arith_ev.word_ev = word_ev
|
| 148 | bool_ev.word_ev = word_ev
|
| 149 |
|
| 150 | if expr_ev: # for pure OSH
|
| 151 | expr_ev.shell_ex = shell_ex
|
| 152 | expr_ev.cmd_ev = cmd_ev
|
| 153 | expr_ev.word_ev = word_ev
|
| 154 |
|
| 155 | word_ev.arith_ev = arith_ev
|
| 156 | word_ev.expr_ev = expr_ev
|
| 157 | word_ev.prompt_ev = prompt_ev
|
| 158 | word_ev.shell_ex = shell_ex
|
| 159 |
|
| 160 | cmd_ev.shell_ex = shell_ex
|
| 161 | cmd_ev.arith_ev = arith_ev
|
| 162 | cmd_ev.bool_ev = bool_ev
|
| 163 | cmd_ev.expr_ev = expr_ev
|
| 164 | cmd_ev.word_ev = word_ev
|
| 165 | cmd_ev.tracer = tracer
|
| 166 |
|
| 167 | shell_ex.cmd_ev = cmd_ev
|
| 168 | pure_ex.cmd_ev = cmd_ev
|
| 169 |
|
| 170 | prompt_ev.word_ev = word_ev
|
| 171 | prompt_ev.expr_ev = expr_ev
|
| 172 | prompt_ev.global_io = global_io
|
| 173 |
|
| 174 | tracer.word_ev = word_ev
|
| 175 |
|
| 176 | arith_ev.CheckCircularDeps()
|
| 177 | bool_ev.CheckCircularDeps()
|
| 178 | if expr_ev:
|
| 179 | expr_ev.CheckCircularDeps()
|
| 180 | word_ev.CheckCircularDeps()
|
| 181 | cmd_ev.CheckCircularDeps()
|
| 182 | shell_ex.CheckCircularDeps()
|
| 183 | pure_ex.CheckCircularDeps()
|
| 184 | prompt_ev.CheckCircularDeps()
|
| 185 | tracer.CheckCircularDeps()
|
| 186 |
|
| 187 |
|
| 188 | class _Executor(object):
|
| 189 |
|
| 190 | def __init__(
|
| 191 | self,
|
| 192 | mem, # type: state.Mem
|
| 193 | exec_opts, # type: optview.Exec
|
| 194 | mutable_opts, # type: state.MutableOpts
|
| 195 | procs, # type: state.Procs
|
| 196 | hay_state, # type: hay_ysh.HayState
|
| 197 | builtins, # type: Dict[int, _Builtin]
|
| 198 | tracer, # type: dev.Tracer
|
| 199 | errfmt # type: ui.ErrorFormatter
|
| 200 | ):
|
| 201 | self.mem = mem
|
| 202 | self.exec_opts = exec_opts
|
| 203 | self.mutable_opts = mutable_opts # for IsDisabled(), not mutating
|
| 204 | self.procs = procs
|
| 205 | self.hay_state = hay_state
|
| 206 | self.builtins = builtins
|
| 207 | self.tracer = tracer
|
| 208 | self.errfmt = errfmt
|
| 209 |
|
| 210 | # Not a constructor argument
|
| 211 | self.cmd_ev = None # type: cmd_eval.CommandEvaluator
|
| 212 |
|
| 213 | def CheckCircularDeps(self):
|
| 214 | # type: () -> None
|
| 215 | assert self.cmd_ev is not None
|
| 216 |
|
| 217 | def RunSimpleCommand(self, cmd_val, cmd_st, run_flags):
|
| 218 | # type: (cmd_value.Argv, CommandStatus, int) -> int
|
| 219 | """Shared between ShellExecutor and PureExecutor"""
|
| 220 | if len(cmd_val.arg_locs):
|
| 221 | arg0_loc = cmd_val.arg_locs[0] # type: loc_t
|
| 222 | else:
|
| 223 | arg0_loc = loc.Missing
|
| 224 |
|
| 225 | argv = cmd_val.argv
|
| 226 | # This happens when you write "$@" but have no arguments.
|
| 227 | if len(argv) == 0:
|
| 228 | if self.exec_opts.strict_argv():
|
| 229 | e_die("Command evaluated to an empty argv array", arg0_loc)
|
| 230 | else:
|
| 231 | return 0 # do nothing
|
| 232 |
|
| 233 | return self._RunSimpleCommand(argv[0], arg0_loc, cmd_val, cmd_st,
|
| 234 | run_flags)
|
| 235 |
|
| 236 | def _RunSimpleCommand(self, arg0, arg0_loc, cmd_val, cmd_st, run_flags):
|
| 237 | # type: (str, loc_t, cmd_value.Argv, CommandStatus, int) -> int
|
| 238 | raise NotImplementedError()
|
| 239 |
|
| 240 | def RunBuiltin(self, builtin_id, cmd_val):
|
| 241 | # type: (int, cmd_value.Argv) -> int
|
| 242 | """Run a builtin.
|
| 243 |
|
| 244 | Also called by the 'builtin' builtin, in builtin/meta_oils.py
|
| 245 | """
|
| 246 | self.tracer.OnBuiltin(builtin_id, cmd_val.argv)
|
| 247 |
|
| 248 | builtin_proc = self.builtins[builtin_id]
|
| 249 |
|
| 250 | return self._RunBuiltinProc(builtin_proc, cmd_val)
|
| 251 |
|
| 252 | def _RunBuiltinProc(self, builtin_proc, cmd_val):
|
| 253 | # type: (_Builtin, cmd_value.Argv) -> int
|
| 254 |
|
| 255 | io_errors = [] # type: List[error.IOError_OSError]
|
| 256 | with ctx_FlushStdout(io_errors):
|
| 257 | # note: could be second word, like 'builtin read'
|
| 258 | with ui.ctx_Location(self.errfmt, cmd_val.arg_locs[0]):
|
| 259 | try:
|
| 260 | status = builtin_proc.Run(cmd_val)
|
| 261 | assert isinstance(status, int)
|
| 262 | except (IOError, OSError) as e:
|
| 263 | self.errfmt.PrintMessage(
|
| 264 | '%s builtin I/O error: %s' %
|
| 265 | (cmd_val.argv[0], pyutil.strerror(e)),
|
| 266 | cmd_val.arg_locs[0])
|
| 267 | return 1
|
| 268 | except error.Usage as e:
|
| 269 | arg0 = cmd_val.argv[0]
|
| 270 | # e.g. 'type' doesn't accept flag '-x'
|
| 271 | self.errfmt.PrefixPrint(e.msg, '%r ' % arg0, e.location)
|
| 272 | return 2 # consistent error code for usage error
|
| 273 |
|
| 274 | if len(io_errors): # e.g. disk full, ulimit
|
| 275 | self.errfmt.PrintMessage(
|
| 276 | '%s builtin I/O error: %s' %
|
| 277 | (cmd_val.argv[0], pyutil.strerror(io_errors[0])),
|
| 278 | cmd_val.arg_locs[0])
|
| 279 | return 1
|
| 280 |
|
| 281 | return status
|
| 282 |
|
| 283 | def _RunInvokable(self, proc_val, self_obj, arg0_loc, cmd_val):
|
| 284 | # type: (value_t, Optional[Obj], loc_t, cmd_value.Argv) -> int
|
| 285 |
|
| 286 | cmd_val.self_obj = self_obj # MAYBE bind self
|
| 287 |
|
| 288 | if self.exec_opts.strict_errexit():
|
| 289 | disabled_tok = self.mutable_opts.ErrExitDisabledToken()
|
| 290 | if disabled_tok:
|
| 291 | self.errfmt.Print_('errexit was disabled for this construct',
|
| 292 | disabled_tok)
|
| 293 | self.errfmt.StderrLine('')
|
| 294 | e_die(
|
| 295 | "Can't run functions or procs while errexit is disabled (OILS-ERR-301)",
|
| 296 | arg0_loc)
|
| 297 |
|
| 298 | with tagswitch(proc_val) as case:
|
| 299 | if case(value_e.BuiltinProc):
|
| 300 | # Handle the special case of the BUILTIN proc
|
| 301 | # module_ysh.ModuleInvoke, which is returned on the Obj
|
| 302 | # created by 'use util.ysh'
|
| 303 | builtin_proc = cast(value.BuiltinProc, proc_val)
|
| 304 | b = cast(_Builtin, builtin_proc.builtin)
|
| 305 | status = self._RunBuiltinProc(b, cmd_val)
|
| 306 |
|
| 307 | elif case(value_e.Proc):
|
| 308 | proc = cast(value.Proc, proc_val)
|
| 309 | with dev.ctx_Tracer(self.tracer, 'proc', cmd_val.argv):
|
| 310 | # NOTE: Functions could call 'exit 42' directly, etc.
|
| 311 | status = self.cmd_ev.RunProc(proc, cmd_val)
|
| 312 |
|
| 313 | else:
|
| 314 | # GetInvokable() should only return 1 of 2 things
|
| 315 | raise AssertionError()
|
| 316 |
|
| 317 | return status
|
| 318 |
|
| 319 | def RunBackgroundJob(self, node):
|
| 320 | # type: (command_t) -> int
|
| 321 | return 0
|
| 322 |
|
| 323 | def RunPipeline(self, node, status_out):
|
| 324 | # type: (command.Pipeline, CommandStatus) -> None
|
| 325 | pass
|
| 326 |
|
| 327 | def RunSubshell(self, node):
|
| 328 | # type: (command_t) -> int
|
| 329 | return 0
|
| 330 |
|
| 331 | def CaptureStdout(self, node):
|
| 332 | # type: (command_t) -> Tuple[int, str]
|
| 333 | return 0, ''
|
| 334 |
|
| 335 | def Capture3(self, node):
|
| 336 | # type: (command_t) -> Tuple[int, str, str]
|
| 337 | return 0, '', ''
|
| 338 |
|
| 339 | def RunCommandSub(self, cs_part):
|
| 340 | # type: (CommandSub) -> str
|
| 341 | return ''
|
| 342 |
|
| 343 | def RunProcessSub(self, cs_part):
|
| 344 | # type: (CommandSub) -> str
|
| 345 | return ''
|
| 346 |
|
| 347 | def PushRedirects(self, redirects, err_out):
|
| 348 | # type: (List[RedirValue], List[error.IOError_OSError]) -> None
|
| 349 | pass
|
| 350 |
|
| 351 | def PopRedirects(self, num_redirects, err_out):
|
| 352 | # type: (int, List[error.IOError_OSError]) -> None
|
| 353 | pass
|
| 354 |
|
| 355 | def PushProcessSub(self):
|
| 356 | # type: () -> None
|
| 357 | pass
|
| 358 |
|
| 359 | def PopProcessSub(self, compound_st):
|
| 360 | # type: (StatusArray) -> None
|
| 361 | pass
|
| 362 |
|
| 363 |
|
| 364 | #
|
| 365 | # Abstract base classes
|
| 366 | #
|
| 367 |
|
| 368 |
|
| 369 | class _AssignBuiltin(object):
|
| 370 | """Interface for assignment builtins."""
|
| 371 |
|
| 372 | def __init__(self):
|
| 373 | # type: () -> None
|
| 374 | """Empty constructor for mycpp."""
|
| 375 | pass
|
| 376 |
|
| 377 | def Run(self, cmd_val):
|
| 378 | # type: (cmd_value.Assign) -> int
|
| 379 | raise NotImplementedError()
|
| 380 |
|
| 381 |
|
| 382 | class _Builtin(object):
|
| 383 | """All builtins except 'command' obey this interface.
|
| 384 |
|
| 385 | Assignment builtins use cmd_value.Assign; others use cmd_value.Argv.
|
| 386 | """
|
| 387 |
|
| 388 | def __init__(self):
|
| 389 | # type: () -> None
|
| 390 | """Empty constructor for mycpp."""
|
| 391 | pass
|
| 392 |
|
| 393 | def Run(self, cmd_val):
|
| 394 | # type: (cmd_value.Argv) -> int
|
| 395 | raise NotImplementedError()
|
| 396 |
|
| 397 |
|
| 398 | class _Callable(object):
|
| 399 | """Interface for functions in the runtime."""
|
| 400 |
|
| 401 | def __init__(self):
|
| 402 | # type: () -> None
|
| 403 | """Empty constructor for mycpp."""
|
| 404 | pass
|
| 405 |
|
| 406 | def Call(self, args):
|
| 407 | # type: (typed_args.Reader) -> value_t
|
| 408 | raise NotImplementedError()
|
| 409 |
|
| 410 |
|
| 411 | class ctx_MaybePure(object):
|
| 412 | """Enforce purity of the shell interpreter
|
| 413 |
|
| 414 | Use this for:
|
| 415 |
|
| 416 | --eval-pure
|
| 417 | func - pure functions
|
| 418 | eval() evalToDict() - builtin pure functions, not methods
|
| 419 | """
|
| 420 |
|
| 421 | def __init__(
|
| 422 | self,
|
| 423 | pure_ex, # type: Optional[_Executor]
|
| 424 | cmd_ev, # type: cmd_eval.CommandEvaluator
|
| 425 | ):
|
| 426 | # type: (...) -> None
|
| 427 | self.pure_ex = pure_ex
|
| 428 | if not pure_ex:
|
| 429 | return # do nothing
|
| 430 |
|
| 431 | word_ev = cmd_ev.word_ev
|
| 432 | expr_ev = cmd_ev.expr_ev
|
| 433 |
|
| 434 | # Save the Shell Executor
|
| 435 | self.saved = cmd_ev.shell_ex
|
| 436 | assert self.saved is word_ev.shell_ex
|
| 437 | assert self.saved is expr_ev.shell_ex
|
| 438 |
|
| 439 | # Patch evaluators to use the Pure Executor
|
| 440 | cmd_ev.shell_ex = pure_ex
|
| 441 | word_ev.shell_ex = pure_ex
|
| 442 | expr_ev.shell_ex = pure_ex
|
| 443 |
|
| 444 | self.cmd_ev = cmd_ev
|
| 445 |
|
| 446 | def __enter__(self):
|
| 447 | # type: () -> None
|
| 448 | pass
|
| 449 |
|
| 450 | def __exit__(self, type, value, traceback):
|
| 451 | # type: (Any, Any, Any) -> None
|
| 452 | if not self.pure_ex:
|
| 453 | return # do nothing
|
| 454 |
|
| 455 | # Unpatch the evaluators
|
| 456 | self.cmd_ev.shell_ex = self.saved
|
| 457 | self.cmd_ev.word_ev.shell_ex = self.saved
|
| 458 | self.cmd_ev.expr_ev.shell_ex = self.saved
|
| 459 |
|
| 460 |
|
| 461 | class ctx_Redirect(object):
|
| 462 | """For closing files.
|
| 463 |
|
| 464 | This is asymmetric because if PushRedirects fails, then we don't execute
|
| 465 | the command at all.
|
| 466 |
|
| 467 | Example:
|
| 468 | { seq 3 > foo.txt; echo 4; } > bar.txt
|
| 469 | """
|
| 470 |
|
| 471 | def __init__(self, shell_ex, num_redirects, err_out):
|
| 472 | # type: (_Executor, int, List[error.IOError_OSError]) -> None
|
| 473 | self.shell_ex = shell_ex
|
| 474 | self.num_redirects = num_redirects
|
| 475 | self.err_out = err_out
|
| 476 |
|
| 477 | def __enter__(self):
|
| 478 | # type: () -> None
|
| 479 | pass
|
| 480 |
|
| 481 | def __exit__(self, type, value, traceback):
|
| 482 | # type: (Any, Any, Any) -> None
|
| 483 | self.shell_ex.PopRedirects(self.num_redirects, self.err_out)
|
| 484 |
|
| 485 |
|
| 486 | class ctx_ProcessSub(object):
|
| 487 | """For waiting on processes started during word evaluation.
|
| 488 |
|
| 489 | Example:
|
| 490 | diff <(seq 3) <(seq 4) > >(tac)
|
| 491 | """
|
| 492 |
|
| 493 | def __init__(self, shell_ex, process_sub_status):
|
| 494 | # type: (_Executor, StatusArray) -> None
|
| 495 | shell_ex.PushProcessSub()
|
| 496 | self.shell_ex = shell_ex
|
| 497 | self.process_sub_status = process_sub_status
|
| 498 |
|
| 499 | def __enter__(self):
|
| 500 | # type: () -> None
|
| 501 | pass
|
| 502 |
|
| 503 | def __exit__(self, type, value, traceback):
|
| 504 | # type: (Any, Any, Any) -> None
|
| 505 |
|
| 506 | # Wait and return array to set _process_sub_status
|
| 507 | self.shell_ex.PopProcessSub(self.process_sub_status)
|
| 508 |
|
| 509 |
|
| 510 | class ctx_FlushStdout(object):
|
| 511 |
|
| 512 | def __init__(self, err_out):
|
| 513 | # type: (List[error.IOError_OSError]) -> None
|
| 514 | self.err_out = err_out
|
| 515 |
|
| 516 | def __enter__(self):
|
| 517 | # type: () -> None
|
| 518 | pass
|
| 519 |
|
| 520 | def __exit__(self, type, value, traceback):
|
| 521 | # type: (Any, Any, Any) -> None
|
| 522 |
|
| 523 | # Can't raise exception in destructor! So we append it to out param.
|
| 524 | err = pyos.FlushStdout()
|
| 525 | if err is not None:
|
| 526 | self.err_out.append(err)
|