OILS / osh / cmd_eval.py View on Github | oilshell.org

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1#!/usr/bin/env python2
2# Copyright 2016 Andy Chu. All rights reserved.
3# Licensed under the Apache License, Version 2.0 (the "License");
4# you may not use this file except in compliance with the License.
5# You may obtain a copy of the License at
6#
7# http://www.apache.org/licenses/LICENSE-2.0
8"""
9cmd_eval.py -- Interpreter for the command language.
10
11Problems:
12$ < Makefile cat | < NOTES.txt head
13
14This just does head? Last one wins.
15"""
16from __future__ import print_function
17
18import sys
19
20from _devbuild.gen.id_kind_asdl import Id
21from _devbuild.gen.option_asdl import option_i
22from _devbuild.gen.syntax_asdl import (
23 IntParamBox,
24 loc,
25 loc_t,
26 loc_e,
27 Token,
28 CompoundWord,
29 command,
30 command_e,
31 command_t,
32 command_str,
33 condition,
34 condition_e,
35 condition_t,
36 case_arg,
37 case_arg_e,
38 case_arg_t,
39 BraceGroup,
40 Proc,
41 Func,
42 assign_op_e,
43 expr_t,
44 proc_sig,
45 proc_sig_e,
46 redir_param,
47 redir_param_e,
48 for_iter,
49 for_iter_e,
50 pat,
51 pat_e,
52 word,
53 Eggex,
54)
55from _devbuild.gen.runtime_asdl import (
56 cmd_value,
57 cmd_value_e,
58 RedirValue,
59 redirect_arg,
60 flow_e,
61 scope_e,
62 CommandStatus,
63 StatusArray,
64)
65from _devbuild.gen.types_asdl import redir_arg_type_e
66from _devbuild.gen.value_asdl import (value, value_e, value_t, y_lvalue,
67 y_lvalue_e, y_lvalue_t, LeftName)
68
69from core import dev
70from core import error
71from core import executor
72from core.error import e_die, e_die_status
73from core import num
74from core import pyos # Time(). TODO: rename
75from core import pyutil
76from core import state
77from core import ui
78from core import util
79from core import vm
80from frontend import consts
81from frontend import lexer
82from frontend import location
83from osh import braces
84from osh import sh_expr_eval
85from osh import word_eval
86from mycpp import mops
87from mycpp import mylib
88from mycpp.mylib import log, probe, switch, tagswitch
89from ysh import expr_eval
90from ysh import func_proc
91from ysh import val_ops
92
93import posix_ as posix
94import libc # for fnmatch
95# Import this name directly because the C++ translation uses macros literally.
96from libc import FNM_CASEFOLD
97
98from typing import List, Dict, Tuple, Optional, Any, cast, TYPE_CHECKING
99
100if TYPE_CHECKING:
101 from _devbuild.gen.option_asdl import builtin_t
102 from _devbuild.gen.runtime_asdl import cmd_value_t
103 from _devbuild.gen.syntax_asdl import Redir, EnvPair
104 from core.alloc import Arena
105 from core import optview
106 from core.vm import _Executor, _AssignBuiltin
107 from builtin import trap_osh
108
109# flags for main_loop.Batch, ExecuteAndCatch. TODO: Should probably in
110# ExecuteAndCatch, along with SetValue() flags.
111IsMainProgram = 1 << 0 # the main shell program, not eval/source/subshell
112RaiseControlFlow = 1 << 1 # eval/source builtins
113Optimize = 1 << 2
114NoDebugTrap = 1 << 3
115NoErrTrap = 1 << 4
116
117
118def MakeBuiltinArgv(argv1):
119 # type: (List[str]) -> cmd_value.Argv
120 argv = [''] # dummy for argv[0]
121 argv.extend(argv1)
122 missing = None # type: CompoundWord
123 return cmd_value.Argv(argv, [missing] * len(argv), None, None, None, None)
124
125
126class Deps(object):
127
128 def __init__(self):
129 # type: () -> None
130 self.mutable_opts = None # type: state.MutableOpts
131 self.dumper = None # type: dev.CrashDumper
132 self.debug_f = None # type: util._DebugFile
133
134
135def _HasManyStatuses(node):
136 # type: (command_t) -> bool
137 """Code patterns that are bad for POSIX errexit. For YSH strict_errexit.
138
139 Note: strict_errexit also uses
140 shopt --unset _allow_command_sub _allow_process_sub
141 """
142 UP_node = node
143 with tagswitch(node) as case:
144 # Atoms.
145 # TODO: Do we need YSH atoms here?
146 if case(command_e.Simple, command_e.DBracket, command_e.DParen):
147 return False
148
149 elif case(command_e.Redirect):
150 node = cast(command.Redirect, UP_node)
151 return _HasManyStatuses(node.child)
152
153 elif case(command_e.Sentence):
154 # Sentence check is for if false; versus if false
155 node = cast(command.Sentence, UP_node)
156 return _HasManyStatuses(node.child)
157
158 elif case(command_e.Pipeline):
159 node = cast(command.Pipeline, UP_node)
160 if len(node.children) == 1:
161 # '! false' is a pipeline that we want to ALLOW
162 # '! ( echo subshell )' is DISALLWOED
163 return _HasManyStatuses(node.children[0])
164 else:
165 # Multiple parts like 'ls | wc' is disallowed
166 return True
167
168 # - ShAssignment could be allowed, though its exit code will always be
169 # 0 without command subs
170 # - Naively, (non-singleton) pipelines could be allowed because pipefail.
171 # BUT could be a proc executed inside a child process, which causes a
172 # problem: the strict_errexit check has to occur at runtime and there's
173 # no way to signal it ot the parent.
174
175 return True
176
177
178def PlusEquals(old_val, val):
179 # type: (value_t, value_t) -> value_t
180 """Implement s+=val, typeset s+=val, etc."""
181
182 UP_old_val = old_val
183 UP_val = val
184
185 tag = val.tag()
186
187 with tagswitch(old_val) as case:
188 if case(value_e.Undef):
189 pass # val is RHS
190
191 elif case(value_e.Str):
192 if tag == value_e.Str:
193 old_val = cast(value.Str, UP_old_val)
194 str_to_append = cast(value.Str, UP_val)
195 val = value.Str(old_val.s + str_to_append.s)
196
197 elif tag == value_e.BashArray:
198 e_die("Can't append array to string")
199
200 else:
201 raise AssertionError() # parsing should prevent this
202
203 elif case(value_e.BashArray):
204 if tag == value_e.Str:
205 e_die("Can't append string to array")
206
207 elif tag == value_e.BashArray:
208 old_val = cast(value.BashArray, UP_old_val)
209 to_append = cast(value.BashArray, UP_val)
210
211 # TODO: MUTATE the existing value for efficiency?
212 strs = [] # type: List[str]
213 strs.extend(old_val.strs)
214 strs.extend(to_append.strs)
215 val = value.BashArray(strs)
216
217 else:
218 raise AssertionError() # parsing should prevent this
219
220 elif case(value_e.BashAssoc):
221 # TODO: Could try to match bash, it will append to ${A[0]}
222 pass
223
224 else:
225 e_die("Can't append to value of type %s" % ui.ValType(old_val))
226
227 return val
228
229
230class ctx_LoopLevel(object):
231 """For checking for invalid control flow."""
232
233 def __init__(self, cmd_ev):
234 # type: (CommandEvaluator) -> None
235 cmd_ev.loop_level += 1
236 self.cmd_ev = cmd_ev
237
238 def __enter__(self):
239 # type: () -> None
240 pass
241
242 def __exit__(self, type, value, traceback):
243 # type: (Any, Any, Any) -> None
244 self.cmd_ev.loop_level -= 1
245
246
247class CommandEvaluator(object):
248 """Executes the program by tree-walking.
249
250 It also does some double-dispatch by passing itself into Eval() for
251 Compound/WordPart.
252 """
253
254 def __init__(
255 self,
256 mem, # type: state.Mem
257 exec_opts, # type: optview.Exec
258 errfmt, # type: ui.ErrorFormatter
259 procs, # type: Dict[str, value.Proc]
260 assign_builtins, # type: Dict[builtin_t, _AssignBuiltin]
261 arena, # type: Arena
262 cmd_deps, # type: Deps
263 trap_state, # type: trap_osh.TrapState
264 signal_safe, # type: pyos.SignalSafe
265 ):
266 # type: (...) -> None
267 """
268 Args:
269 mem: Mem instance for storing variables
270 procs: dict of SHELL functions or 'procs'
271 builtins: dict of builtin callables
272 TODO: This should only be for assignment builtins?
273 cmd_deps: A bundle of stateless code
274 """
275 self.shell_ex = None # type: _Executor
276 self.arith_ev = None # type: sh_expr_eval.ArithEvaluator
277 self.bool_ev = None # type: sh_expr_eval.BoolEvaluator
278 self.expr_ev = None # type: expr_eval.ExprEvaluator
279 self.word_ev = None # type: word_eval.AbstractWordEvaluator
280 self.tracer = None # type: dev.Tracer
281
282 self.mem = mem
283 # This is for shopt and set -o. They are initialized by flags.
284 self.exec_opts = exec_opts
285 self.errfmt = errfmt
286 self.procs = procs
287 self.assign_builtins = assign_builtins
288 self.arena = arena
289
290 self.mutable_opts = cmd_deps.mutable_opts
291 self.dumper = cmd_deps.dumper
292 self.debug_f = cmd_deps.debug_f # Used by ShellFuncAction too
293
294 self.trap_state = trap_state
295 self.signal_safe = signal_safe
296
297 self.loop_level = 0 # for detecting bad top-level break/continue
298 self.check_command_sub_status = False # a hack. Modified by ShellExecutor
299
300 self.status_array_pool = [] # type: List[StatusArray]
301
302 def CheckCircularDeps(self):
303 # type: () -> None
304 assert self.arith_ev is not None
305 assert self.bool_ev is not None
306 # Disabled for push OSH
307 #assert self.expr_ev is not None
308 assert self.word_ev is not None
309
310 def _RunAssignBuiltin(self, cmd_val):
311 # type: (cmd_value.Assign) -> int
312 """Run an assignment builtin.
313
314 Except blocks copied from RunBuiltin.
315 """
316 builtin_func = self.assign_builtins.get(cmd_val.builtin_id)
317 if builtin_func is None:
318 # This only happens with alternative Oils interpreters.
319 e_die("Assignment builtin %r not configured" % cmd_val.argv[0],
320 cmd_val.arg_locs[0])
321
322 io_errors = [] # type: List[error.IOError_OSError]
323 with vm.ctx_FlushStdout(io_errors):
324 with ui.ctx_Location(self.errfmt, cmd_val.arg_locs[0]):
325 try:
326 status = builtin_func.Run(cmd_val)
327 except (IOError, OSError) as e:
328 # e.g. declare -p > /dev/full
329 self.errfmt.PrintMessage(
330 '%s builtin I/O error: %s' %
331 (cmd_val.argv[0], pyutil.strerror(e)),
332 cmd_val.arg_locs[0])
333 return 1
334 except error.Usage as e: # Copied from RunBuiltin
335 arg0 = cmd_val.argv[0]
336 self.errfmt.PrefixPrint(e.msg, '%r ' % arg0, e.location)
337 return 2 # consistent error code for usage error
338
339 if len(io_errors): # e.g. declare -p > /dev/full
340 self.errfmt.PrintMessage(
341 '%s builtin I/O: %s' %
342 (cmd_val.argv[0], pyutil.strerror(io_errors[0])),
343 cmd_val.arg_locs[0])
344 return 1
345
346 return status
347
348 def _CheckStatus(self, status, cmd_st, node, default_loc):
349 # type: (int, CommandStatus, command_t, loc_t) -> None
350 """Raises error.ErrExit, maybe with location info attached."""
351
352 assert status >= 0, status
353
354 if status == 0:
355 return # Nothing to do
356
357 self._MaybeRunErrTrap()
358
359 if self.exec_opts.errexit():
360 # NOTE: Sometimes we print 2 errors
361 # - 'type -z' has a UsageError with location, then errexit
362 # - '> /nonexistent' has an I/O error, then errexit
363 # - Pipelines and subshells are compound. Commands within them fail.
364 # - however ( exit 33 ) only prints one message.
365 #
366 # But we will want something like 'false' to have location info.
367
368 UP_node = node
369 with tagswitch(node) as case:
370 if case(command_e.ShAssignment):
371 node = cast(command.ShAssignment, UP_node)
372 cmd_st.show_code = True # leaf
373 # Note: we show errors from assignments a=$(false) rarely: when
374 # errexit, inherit_errexit, verbose_errexit are on, but
375 # command_sub_errexit is off!
376
377 # Note: a subshell often doesn't fail on its own.
378 elif case(command_e.Subshell):
379 node = cast(command.Subshell, UP_node)
380 cmd_st.show_code = True # not sure about this, e.g. ( exit 42 )
381
382 elif case(command_e.Pipeline):
383 node = cast(command.Pipeline, UP_node)
384 cmd_st.show_code = True # not sure about this
385 # TODO: We should show which element of the pipeline failed!
386
387 desc = command_str(node.tag())
388
389 # Override location if explicitly passed.
390 # Note: this produces better results for process sub
391 # echo <(sort x)
392 # and different results for some pipelines:
393 # { ls; false; } | wc -l; echo hi # Point to | or first { ?
394 if default_loc.tag() != loc_e.Missing:
395 blame_loc = default_loc # type: loc_t
396 else:
397 blame_loc = location.TokenForCommand(node)
398
399 msg = '%s failed with status %d' % (desc, status)
400 raise error.ErrExit(status,
401 msg,
402 blame_loc,
403 show_code=cmd_st.show_code)
404
405 def _EvalRedirect(self, r):
406 # type: (Redir) -> RedirValue
407
408 result = RedirValue(r.op.id, r.op, r.loc, None)
409
410 arg = r.arg
411 UP_arg = arg
412 with tagswitch(arg) as case:
413 if case(redir_param_e.Word):
414 arg_word = cast(CompoundWord, UP_arg)
415
416 # Note: needed for redirect like 'echo foo > x$LINENO'
417 self.mem.SetTokenForLine(r.op)
418
419 # Could be computed at parse time?
420 redir_type = consts.RedirArgType(r.op.id)
421
422 if redir_type == redir_arg_type_e.Path:
423 # Redirects with path arguments are evaluated in a special
424 # way. bash and zsh allow globbing a path, but
425 # dash/ash/mksh don't.
426 #
427 # If there are multiple files, zsh opens BOTH, but bash
428 # makes the command fail with status 1. We mostly follow
429 # bash behavior.
430
431 # These don't match bash/zsh behavior
432 # val = self.word_ev.EvalWordToString(arg_word)
433 # val, has_extglob = self.word_ev.EvalWordToPattern(arg_word)
434 # Short-circuit with word_.StaticEval() also doesn't work
435 # with globs
436
437 # mycpp needs this explicit declaration
438 b = braces.BraceDetect(
439 arg_word) # type: Optional[word.BracedTree]
440 if b is not None:
441 raise error.RedirectEval(
442 'Brace expansion not allowed (try adding quotes)',
443 arg_word)
444
445 # Needed for globbing behavior
446 files = self.word_ev.EvalWordSequence([arg_word])
447
448 n = len(files)
449 if n == 0:
450 # happens in OSH on empty elision
451 # in YSH because simple_word_eval globs to zero
452 raise error.RedirectEval(
453 "Can't redirect to zero files", arg_word)
454 if n > 1:
455 raise error.RedirectEval(
456 "Can't redirect to more than one file", arg_word)
457
458 result.arg = redirect_arg.Path(files[0])
459 return result
460
461 elif redir_type == redir_arg_type_e.Desc: # e.g. 1>&2, 1>&-, 1>&2-
462 val = self.word_ev.EvalWordToString(arg_word)
463 t = val.s
464 if len(t) == 0:
465 raise error.RedirectEval(
466 "Redirect descriptor can't be empty", arg_word)
467 return None
468
469 try:
470 if t == '-':
471 result.arg = redirect_arg.CloseFd
472 elif t[-1] == '-':
473 target_fd = int(t[:-1])
474 result.arg = redirect_arg.MoveFd(target_fd)
475 else:
476 result.arg = redirect_arg.CopyFd(int(t))
477 except ValueError:
478 raise error.RedirectEval(
479 'Invalid descriptor %r. Expected D, -, or D- where D is an '
480 'integer' % t, arg_word)
481 return None
482
483 return result
484
485 elif redir_type == redir_arg_type_e.Here: # here word
486 val = self.word_ev.EvalWordToString(arg_word)
487 assert val.tag() == value_e.Str, val
488 # NOTE: bash and mksh both add \n
489 result.arg = redirect_arg.HereDoc(val.s + '\n')
490 return result
491
492 else:
493 raise AssertionError('Unknown redirect op')
494
495 elif case(redir_param_e.HereDoc):
496 arg = cast(redir_param.HereDoc, UP_arg)
497 w = CompoundWord(
498 arg.stdin_parts) # HACK: Wrap it in a word to eval
499 val = self.word_ev.EvalWordToString(w)
500 assert val.tag() == value_e.Str, val
501 result.arg = redirect_arg.HereDoc(val.s)
502 return result
503
504 else:
505 raise AssertionError('Unknown redirect type')
506
507 raise AssertionError('for -Wreturn-type in C++')
508
509 def _RunSimpleCommand(self, cmd_val, cmd_st, run_flags):
510 # type: (cmd_value_t, CommandStatus, int) -> int
511 """Private interface to run a simple command (including assignment)."""
512 UP_cmd_val = cmd_val
513 with tagswitch(UP_cmd_val) as case:
514 if case(cmd_value_e.Argv):
515 cmd_val = cast(cmd_value.Argv, UP_cmd_val)
516 self.tracer.OnSimpleCommand(cmd_val.argv)
517 return self.shell_ex.RunSimpleCommand(cmd_val, cmd_st,
518 run_flags)
519
520 elif case(cmd_value_e.Assign):
521 cmd_val = cast(cmd_value.Assign, UP_cmd_val)
522 self.tracer.OnAssignBuiltin(cmd_val)
523 return self._RunAssignBuiltin(cmd_val)
524
525 else:
526 raise AssertionError()
527
528 def _EvalTempEnv(self, more_env, flags):
529 # type: (List[EnvPair], int) -> None
530 """For FOO=1 cmd."""
531 for e_pair in more_env:
532 val = self.word_ev.EvalRhsWord(e_pair.val)
533 # Set each var so the next one can reference it. Example:
534 # FOO=1 BAR=$FOO ls /
535 self.mem.SetNamed(location.LName(e_pair.name),
536 val,
537 scope_e.LocalOnly,
538 flags=flags)
539
540 def _StrictErrExit(self, node):
541 # type: (command_t) -> None
542 if not (self.exec_opts.errexit() and self.exec_opts.strict_errexit()):
543 return
544
545 if _HasManyStatuses(node):
546 node_str = ui.CommandType(node)
547 e_die(
548 "strict_errexit only allows simple commands in conditionals (got %s). "
549 % node_str, loc.Command(node))
550
551 def _StrictErrExitList(self, node_list):
552 # type: (List[command_t]) -> None
553 """Not allowed, too confusing:
554
555 if grep foo eggs.txt; grep bar eggs.txt; then echo hi fi
556 """
557 if not (self.exec_opts.errexit() and self.exec_opts.strict_errexit()):
558 return
559
560 if len(node_list) > 1:
561 e_die(
562 "strict_errexit only allows a single command. Hint: use 'try'.",
563 loc.Command(node_list[0]))
564
565 assert len(node_list) > 0
566 node = node_list[0]
567 if _HasManyStatuses(node):
568 # TODO: consolidate error message with above
569 node_str = ui.CommandType(node)
570 e_die(
571 "strict_errexit only allows simple commands in conditionals (got %s). "
572 % node_str, loc.Command(node))
573
574 def _EvalCondition(self, cond, blame_tok):
575 # type: (condition_t, Token) -> bool
576 """
577 Args:
578 spid: for OSH conditions, where errexit was disabled -- e.g. if
579 for YSH conditions, it would be nice to blame the ( instead
580 """
581 b = False
582 UP_cond = cond
583 with tagswitch(cond) as case:
584 if case(condition_e.Shell):
585 cond = cast(condition.Shell, UP_cond)
586 self._StrictErrExitList(cond.commands)
587 with state.ctx_ErrExit(self.mutable_opts, False, blame_tok):
588 cond_status = self._ExecuteList(cond.commands)
589
590 b = cond_status == 0
591
592 elif case(condition_e.YshExpr):
593 cond = cast(condition.YshExpr, UP_cond)
594 obj = self.expr_ev.EvalExpr(cond.e, blame_tok)
595 b = val_ops.ToBool(obj)
596
597 return b
598
599 def _EvalCaseArg(self, arg, blame):
600 # type: (case_arg_t, loc_t) -> value_t
601 """Evaluate a `case_arg` into a `value_t` which can be matched on in a case
602 command.
603 """
604 UP_arg = arg
605 with tagswitch(arg) as case:
606 if case(case_arg_e.Word):
607 arg = cast(case_arg.Word, UP_arg)
608 return self.word_ev.EvalWordToString(arg.w)
609
610 elif case(case_arg_e.YshExpr):
611 arg = cast(case_arg.YshExpr, UP_arg)
612 return self.expr_ev.EvalExpr(arg.e, blame)
613
614 else:
615 raise NotImplementedError()
616
617 def _DoVarDecl(self, node):
618 # type: (command.VarDecl) -> int
619 # x = 'foo' in Hay blocks
620 if node.keyword is None:
621 # Note: there's only one LHS
622 lhs0 = node.lhs[0]
623 lval = LeftName(lhs0.name, lhs0.left)
624 assert node.rhs is not None, node
625 val = self.expr_ev.EvalExpr(node.rhs, loc.Missing)
626
627 self.mem.SetNamed(lval,
628 val,
629 scope_e.LocalOnly,
630 flags=state.SetReadOnly)
631
632 else: # var or const
633 flags = (state.SetReadOnly
634 if node.keyword.id == Id.KW_Const else 0)
635
636 # var x, y does null initialization
637 if node.rhs is None:
638 for i, lhs_val in enumerate(node.lhs):
639 lval = LeftName(lhs_val.name, lhs_val.left)
640 self.mem.SetNamed(lval,
641 value.Null,
642 scope_e.LocalOnly,
643 flags=flags)
644 return 0
645
646 right_val = self.expr_ev.EvalExpr(node.rhs, loc.Missing)
647 lvals = None # type: List[LeftName]
648 rhs_vals = None # type: List[value_t]
649
650 num_lhs = len(node.lhs)
651 if num_lhs == 1:
652 lhs0 = node.lhs[0]
653 lvals = [LeftName(lhs0.name, lhs0.left)]
654 rhs_vals = [right_val]
655 else:
656 items = val_ops.ToList(
657 right_val, 'Destructuring assignment expected List',
658 node.keyword)
659
660 num_rhs = len(items)
661 if num_lhs != num_rhs:
662 raise error.Expr(
663 'Got %d places on the left, but %d values on right' %
664 (num_lhs, num_rhs), node.keyword)
665
666 lvals = []
667 rhs_vals = []
668 for i, lhs_val in enumerate(node.lhs):
669 lval = LeftName(lhs_val.name, lhs_val.left)
670 lvals.append(lval)
671 rhs_vals.append(items[i])
672
673 for i, lval in enumerate(lvals):
674 rval = rhs_vals[i]
675 self.mem.SetNamed(lval, rval, scope_e.LocalOnly, flags=flags)
676
677 return 0
678
679 def _DoMutation(self, node):
680 # type: (command.Mutation) -> None
681
682 with switch(node.keyword.id) as case2:
683 if case2(Id.KW_SetVar):
684 which_scopes = scope_e.LocalOnly
685 elif case2(Id.KW_SetGlobal):
686 which_scopes = scope_e.GlobalOnly
687 else:
688 raise AssertionError(node.keyword.id)
689
690 if node.op.id == Id.Arith_Equal:
691 right_val = self.expr_ev.EvalExpr(node.rhs, loc.Missing)
692
693 lvals = None # type: List[y_lvalue_t]
694 rhs_vals = None # type: List[value_t]
695
696 num_lhs = len(node.lhs)
697 if num_lhs == 1:
698 lvals = [self.expr_ev.EvalLhsExpr(node.lhs[0], which_scopes)]
699 rhs_vals = [right_val]
700 else:
701 items = val_ops.ToList(
702 right_val, 'Destructuring assignment expected List',
703 node.keyword)
704
705 num_rhs = len(items)
706 if num_lhs != num_rhs:
707 raise error.Expr(
708 'Got %d places on the left, but %d values on the right'
709 % (num_lhs, num_rhs), node.keyword)
710
711 lvals = []
712 rhs_vals = []
713 for i, lhs_val in enumerate(node.lhs):
714 lvals.append(
715 self.expr_ev.EvalLhsExpr(lhs_val, which_scopes))
716 rhs_vals.append(items[i])
717
718 for i, lval in enumerate(lvals):
719 rval = rhs_vals[i]
720
721 # setvar mylist[0] = 42
722 # setvar mydict['key'] = 42
723 UP_lval = lval
724
725 if lval.tag() == y_lvalue_e.Local:
726 lval = cast(LeftName, UP_lval)
727
728 self.mem.SetNamed(lval, rval, which_scopes)
729
730 elif lval.tag() == y_lvalue_e.Container:
731 lval = cast(y_lvalue.Container, UP_lval)
732
733 obj = lval.obj
734 UP_obj = obj
735 with tagswitch(obj) as case:
736 if case(value_e.List):
737 obj = cast(value.List, UP_obj)
738 index = val_ops.ToInt(lval.index,
739 'List index should be Int',
740 loc.Missing)
741 obj.items[index] = rval
742
743 elif case(value_e.Dict):
744 obj = cast(value.Dict, UP_obj)
745 key = val_ops.ToStr(lval.index,
746 'Dict index should be Str',
747 loc.Missing)
748 obj.d[key] = rval
749
750 else:
751 raise error.TypeErr(
752 obj, "obj[index] expected List or Dict",
753 loc.Missing)
754
755 else:
756 raise AssertionError()
757
758 else:
759 # Checked in the parser
760 assert len(node.lhs) == 1
761
762 aug_lval = self.expr_ev.EvalLhsExpr(node.lhs[0], which_scopes)
763 val = self.expr_ev.EvalExpr(node.rhs, loc.Missing)
764
765 self.expr_ev.EvalAugmented(aug_lval, val, node.op, which_scopes)
766
767 def _DoSimple(self, node, cmd_st):
768 # type: (command.Simple, CommandStatus) -> int
769 probe('cmd_eval', '_DoSimple_enter')
770
771 # PROBLEM: We want to log argv in 'xtrace' mode, but we may have already
772 # redirected here, which screws up logging. For example, 'echo hi
773 # >/dev/null 2>&1'. We want to evaluate argv and log it BEFORE applying
774 # redirects.
775
776 # Another problem:
777 # - tracing can be called concurrently from multiple processes, leading
778 # to overlap. Maybe have a mode that creates a file per process.
779 # xtrace-proc
780 # - line numbers for every command would be very nice. But then you have
781 # to print the filename too.
782
783 words = braces.BraceExpandWords(node.words)
784
785 # Note: Individual WORDS can fail
786 # - $() and <() can have failures. This can happen in DBracket,
787 # DParen, etc. too
788 # - Tracing: this can start processes for proc sub and here docs!
789 cmd_val = self.word_ev.EvalWordSequence2(words, allow_assign=True)
790
791 UP_cmd_val = cmd_val
792 if UP_cmd_val.tag() == cmd_value_e.Argv:
793 cmd_val = cast(cmd_value.Argv, UP_cmd_val)
794
795 if len(cmd_val.argv): # it can be empty in rare cases
796 self.mem.SetLastArgument(cmd_val.argv[-1])
797 else:
798 self.mem.SetLastArgument('')
799
800 if node.typed_args or node.block: # guard to avoid allocs
801 func_proc.EvalTypedArgsToProc(self.expr_ev, self.mutable_opts,
802 node, cmd_val)
803 else:
804 if node.block:
805 e_die("ShAssignment builtins don't accept blocks",
806 node.block.brace_group.left)
807 cmd_val = cast(cmd_value.Assign, UP_cmd_val)
808
809 # Could reset $_ after assignment, but then we'd have to do it for
810 # all YSH constructs too. It's easier to let it persist. Other
811 # shells aren't consistent.
812 # self.mem.SetLastArgument('')
813
814 run_flags = executor.DO_FORK if node.do_fork else 0
815 # NOTE: RunSimpleCommand never returns when do_fork=False!
816 if len(node.more_env): # I think this guard is necessary?
817 is_other_special = False # TODO: There are other special builtins too!
818 if cmd_val.tag() == cmd_value_e.Assign or is_other_special:
819 # Special builtins have their temp env persisted.
820 self._EvalTempEnv(node.more_env, 0)
821 status = self._RunSimpleCommand(cmd_val, cmd_st, run_flags)
822 else:
823 with state.ctx_Temp(self.mem):
824 self._EvalTempEnv(node.more_env, state.SetExport)
825 status = self._RunSimpleCommand(cmd_val, cmd_st, run_flags)
826 else:
827 status = self._RunSimpleCommand(cmd_val, cmd_st, run_flags)
828
829 probe('cmd_eval', '_DoSimple_exit', status)
830 return status
831
832 def _DoExpandedAlias(self, node):
833 # type: (command.ExpandedAlias) -> int
834 # Expanded aliases need redirects and env bindings from the calling
835 # context, as well as redirects in the expansion!
836
837 # TODO: SetTokenForLine to OUTSIDE? Don't bother with stuff inside
838 # expansion, since aliases are discouraged.
839
840 if len(node.more_env):
841 with state.ctx_Temp(self.mem):
842 self._EvalTempEnv(node.more_env, state.SetExport)
843 return self._Execute(node.child)
844 else:
845 return self._Execute(node.child)
846
847 def _DoPipeline(self, node, cmd_st):
848 # type: (command.Pipeline, CommandStatus) -> int
849 cmd_st.check_errexit = True
850 for op in node.ops:
851 if op.id != Id.Op_Pipe:
852 e_die("|& isn't supported", op)
853
854 # Remove $_ before pipeline. This matches bash, and is important in
855 # pipelines than assignments because pipelines are non-deterministic.
856 self.mem.SetLastArgument('')
857
858 # Set status to INVALID value, because we MIGHT set cmd_st.pipe_status,
859 # which _Execute() boils down into a status for us.
860 status = -1
861
862 if node.negated is not None:
863 self._StrictErrExit(node)
864 with state.ctx_ErrExit(self.mutable_opts, False, node.negated):
865 # '! grep' is parsed as a pipeline, according to the grammar, but
866 # there's no pipe() call.
867 if len(node.children) == 1:
868 tmp_status = self._Execute(node.children[0])
869 status = 1 if tmp_status == 0 else 0
870 else:
871 self.shell_ex.RunPipeline(node, cmd_st)
872 cmd_st.pipe_negated = True
873
874 # errexit is disabled for !.
875 cmd_st.check_errexit = False
876 else:
877 self.shell_ex.RunPipeline(node, cmd_st)
878
879 return status
880
881 def _DoShAssignment(self, node, cmd_st):
882 # type: (command.ShAssignment, CommandStatus) -> int
883 assert len(node.pairs) >= 1, node
884
885 # x=y is 'neutered' inside 'proc'
886 which_scopes = self.mem.ScopesForWriting()
887
888 for pair in node.pairs:
889 if pair.op == assign_op_e.PlusEqual:
890 assert pair.rhs, pair.rhs # I don't think a+= is valid?
891 rhs = self.word_ev.EvalRhsWord(pair.rhs)
892
893 lval = self.arith_ev.EvalShellLhs(pair.lhs, which_scopes)
894 # do not respect set -u
895 old_val = sh_expr_eval.OldValue(lval, self.mem, None)
896
897 val = PlusEquals(old_val, rhs)
898
899 else: # plain assignment
900 lval = self.arith_ev.EvalShellLhs(pair.lhs, which_scopes)
901
902 # RHS can be a string or array.
903 if pair.rhs:
904 val = self.word_ev.EvalRhsWord(pair.rhs)
905 assert isinstance(val, value_t), val
906
907 else: # e.g. 'readonly x' or 'local x'
908 val = None
909
910 # NOTE: In bash and mksh, declare -a myarray makes an empty cell
911 # with Undef value, but the 'array' attribute.
912
913 flags = 0 # for tracing
914 self.mem.SetValue(lval, val, which_scopes, flags=flags)
915 self.tracer.OnShAssignment(lval, pair.op, val, flags, which_scopes)
916
917 # PATCH to be compatible with existing shells: If the assignment had a
918 # command sub like:
919 #
920 # s=$(echo one; false)
921 #
922 # then its status will be in mem.last_status, and we can check it here.
923 # If there was NOT a command sub in the assignment, then we don't want to
924 # check it.
925
926 # Only do this if there was a command sub? How? Look at node?
927 # Set a flag in mem? self.mem.last_status or
928 if self.check_command_sub_status:
929 last_status = self.mem.LastStatus()
930 self._CheckStatus(last_status, cmd_st, node, loc.Missing)
931 return last_status # A global assignment shouldn't clear $?.
932 else:
933 return 0
934
935 def _DoExpr(self, node):
936 # type: (command.Expr) -> int
937
938 # call f(x) or = f(x)
939 val = self.expr_ev.EvalExpr(node.e, loc.Missing)
940
941 if node.keyword.id == Id.Lit_Equals: # = f(x)
942 io_errors = [] # type: List[error.IOError_OSError]
943 with vm.ctx_FlushStdout(io_errors):
944 try:
945 ui.PrettyPrintValue(val, mylib.Stdout())
946 except (IOError, OSError) as e:
947 self.errfmt.PrintMessage(
948 'I/O error during = keyword: %s' % pyutil.strerror(e),
949 node.keyword)
950 return 1
951
952 if len(io_errors): # e.g. disk full, ulimit
953 self.errfmt.PrintMessage(
954 'I/O error during = keyword: %s' %
955 pyutil.strerror(io_errors[0]), node.keyword)
956 return 1
957
958 return 0
959
960 def _DoControlFlow(self, node):
961 # type: (command.ControlFlow) -> int
962 keyword = node.keyword
963
964 if node.arg_word: # Evaluate the argument
965 str_val = self.word_ev.EvalWordToString(node.arg_word)
966
967 # Quirk: We need 'return $empty' to be valid for libtool. This is
968 # another meaning of strict_control_flow, which also has to do with
969 # break/continue at top level. It has the side effect of making
970 # 'return ""' valid, which shells other than zsh fail on.
971 if (len(str_val.s) == 0 and
972 not self.exec_opts.strict_control_flow()):
973 arg = 0
974 else:
975 try:
976 arg = int(str_val.s) # all control flow takes an integer
977 except ValueError:
978 # Either a bad argument, or integer overflow
979 e_die(
980 '%r expected a small integer, got %r' %
981 (lexer.TokenVal(keyword), str_val.s),
982 loc.Word(node.arg_word))
983
984 # C++ int() does range checking, but Python doesn't. So let's
985 # simulate it here for spec tests.
986 # TODO: could be mylib.ToMachineInt()? Problem: 'int' in C/C++
987 # could be more than 4 bytes. We are testing INT_MAX and
988 # INT_MIN in gc_builtins.cc - those could be hard-coded.
989 if mylib.PYTHON:
990 max_int = (1 << 31) - 1
991 min_int = -(1 << 31)
992 if not (min_int <= arg <= max_int):
993 e_die(
994 '%r expected a small integer, got %r' %
995 (lexer.TokenVal(keyword), str_val.s),
996 loc.Word(node.arg_word))
997 else:
998 if keyword.id in (Id.ControlFlow_Exit, Id.ControlFlow_Return):
999 arg = self.mem.LastStatus()
1000 else:
1001 arg = 1 # break or continue 1 level by default
1002
1003 self.tracer.OnControlFlow(consts.ControlFlowName(keyword.id), arg)
1004
1005 # NOTE: A top-level 'return' is OK, unlike in bash. If you can return
1006 # from a sourced script, it makes sense to return from a main script.
1007 if (keyword.id in (Id.ControlFlow_Break, Id.ControlFlow_Continue) and
1008 self.loop_level == 0):
1009 msg = 'Invalid control flow at top level'
1010 if self.exec_opts.strict_control_flow():
1011 e_die(msg, keyword)
1012 else:
1013 # Only print warnings, never fatal.
1014 # Bash oddly only exits 1 for 'return', but no other shell does.
1015 self.errfmt.PrefixPrint(msg, 'warning: ', keyword)
1016 return 0
1017
1018 if keyword.id == Id.ControlFlow_Exit:
1019 # handled differently than other control flow
1020 raise util.UserExit(arg)
1021 else:
1022 raise vm.IntControlFlow(keyword, arg)
1023
1024 def _DoAndOr(self, node, cmd_st):
1025 # type: (command.AndOr, CommandStatus) -> int
1026 # NOTE: && and || have EQUAL precedence in command mode. See case #13
1027 # in dbracket.test.sh.
1028
1029 left = node.children[0]
1030
1031 # Suppress failure for every child except the last one.
1032 self._StrictErrExit(left)
1033 with state.ctx_ErrExit(self.mutable_opts, False, node.ops[0]):
1034 status = self._Execute(left)
1035
1036 i = 1
1037 n = len(node.children)
1038 while i < n:
1039 #log('i %d status %d', i, status)
1040 child = node.children[i]
1041 op = node.ops[i - 1]
1042 op_id = op.id
1043
1044 #log('child %s op_id %s', child, op_id)
1045
1046 if op_id == Id.Op_DPipe and status == 0:
1047 i += 1
1048 continue # short circuit
1049
1050 elif op_id == Id.Op_DAmp and status != 0:
1051 i += 1
1052 continue # short circuit
1053
1054 if i == n - 1: # errexit handled differently for last child
1055 status = self._Execute(child)
1056 else:
1057 # blame the right && or ||
1058 self._StrictErrExit(child)
1059 with state.ctx_ErrExit(self.mutable_opts, False, op):
1060 status = self._Execute(child)
1061
1062 i += 1
1063
1064 return status
1065
1066 def _DoWhileUntil(self, node):
1067 # type: (command.WhileUntil) -> int
1068 status = 0
1069 with ctx_LoopLevel(self):
1070 while True:
1071 try:
1072 # blame while/until spid
1073 b = self._EvalCondition(node.cond, node.keyword)
1074 if node.keyword.id == Id.KW_Until:
1075 b = not b
1076 if not b:
1077 break
1078 status = self._Execute(node.body) # last one wins
1079
1080 except vm.IntControlFlow as e:
1081 status = 0
1082 action = e.HandleLoop()
1083 if action == flow_e.Break:
1084 break
1085 elif action == flow_e.Raise:
1086 raise
1087
1088 return status
1089
1090 def _DoForEach(self, node):
1091 # type: (command.ForEach) -> int
1092
1093 # for the 2 kinds of shell loop
1094 iter_list = None # type: List[str]
1095
1096 # for YSH loop
1097 iter_expr = None # type: expr_t
1098 expr_blame = None # type: loc_t
1099
1100 iterable = node.iterable
1101 UP_iterable = iterable
1102
1103 with tagswitch(node.iterable) as case:
1104 if case(for_iter_e.Args):
1105 iter_list = self.mem.GetArgv()
1106
1107 elif case(for_iter_e.Words):
1108 iterable = cast(for_iter.Words, UP_iterable)
1109 words = braces.BraceExpandWords(iterable.words)
1110 iter_list = self.word_ev.EvalWordSequence(words)
1111
1112 elif case(for_iter_e.YshExpr):
1113 iterable = cast(for_iter.YshExpr, UP_iterable)
1114 iter_expr = iterable.e
1115 expr_blame = iterable.blame
1116
1117 else:
1118 raise AssertionError()
1119
1120 n = len(node.iter_names)
1121 assert n > 0
1122
1123 i_name = None # type: Optional[LeftName]
1124 # required
1125 name1 = None # type: LeftName
1126 name2 = None # type: Optional[LeftName]
1127
1128 it2 = None # type: val_ops.Iterator
1129 if iter_expr: # for_expr.YshExpr
1130 val = self.expr_ev.EvalExpr(iter_expr, expr_blame)
1131
1132 UP_val = val
1133 with tagswitch(val) as case:
1134 if case(value_e.List):
1135 val = cast(value.List, UP_val)
1136 it2 = val_ops.ListIterator(val)
1137
1138 if n == 1:
1139 name1 = location.LName(node.iter_names[0])
1140 elif n == 2:
1141 i_name = location.LName(node.iter_names[0])
1142 name1 = location.LName(node.iter_names[1])
1143 else:
1144 # This is similar to a parse error
1145 e_die_status(
1146 2,
1147 'List iteration expects at most 2 loop variables',
1148 node.keyword)
1149
1150 elif case(value_e.Dict):
1151 val = cast(value.Dict, UP_val)
1152 it2 = val_ops.DictIterator(val)
1153
1154 if n == 1:
1155 name1 = location.LName(node.iter_names[0])
1156 elif n == 2:
1157 name1 = location.LName(node.iter_names[0])
1158 name2 = location.LName(node.iter_names[1])
1159 elif n == 3:
1160 i_name = location.LName(node.iter_names[0])
1161 name1 = location.LName(node.iter_names[1])
1162 name2 = location.LName(node.iter_names[2])
1163 else:
1164 raise AssertionError()
1165
1166 elif case(value_e.Range):
1167 val = cast(value.Range, UP_val)
1168 it2 = val_ops.RangeIterator(val)
1169
1170 if n == 1:
1171 name1 = location.LName(node.iter_names[0])
1172 elif n == 2:
1173 i_name = location.LName(node.iter_names[0])
1174 name1 = location.LName(node.iter_names[1])
1175 else:
1176 e_die_status(
1177 2,
1178 'Range iteration expects at most 2 loop variables',
1179 node.keyword)
1180
1181 elif case(value_e.Stdin):
1182 # TODO: This could changed to magic iterator?
1183 it2 = val_ops.StdinIterator(expr_blame)
1184 if n == 1:
1185 name1 = location.LName(node.iter_names[0])
1186 elif n == 2:
1187 i_name = location.LName(node.iter_names[0])
1188 name1 = location.LName(node.iter_names[1])
1189 else:
1190 e_die_status(
1191 2,
1192 'Stdin iteration expects at most 2 loop variables',
1193 node.keyword)
1194 else:
1195 raise error.TypeErr(
1196 val, 'for loop expected List, Dict, Range, or Stdin',
1197 node.keyword)
1198
1199 else:
1200 assert iter_list is not None, iter_list
1201
1202 #log('iter list %s', iter_list)
1203 it2 = val_ops.ArrayIter(iter_list)
1204
1205 if n == 1:
1206 name1 = location.LName(node.iter_names[0])
1207 elif n == 2:
1208 i_name = location.LName(node.iter_names[0])
1209 name1 = location.LName(node.iter_names[1])
1210 else:
1211 # This is similar to a parse error
1212 e_die_status(
1213 2, 'Argv iteration expects at most 2 loop variables',
1214 node.keyword)
1215
1216 status = 0 # in case we loop zero times
1217 with ctx_LoopLevel(self):
1218 while True:
1219 first = it2.FirstValue()
1220 #log('first %s', first)
1221 if first is None: # for StdinIterator
1222 #log('first is None')
1223 break
1224
1225 if first.tag() == value_e.Interrupted:
1226 self.RunPendingTraps()
1227 #log('Done running traps')
1228 continue
1229
1230 self.mem.SetLocalName(name1, first)
1231 if name2:
1232 self.mem.SetLocalName(name2, it2.SecondValue())
1233 if i_name:
1234 self.mem.SetLocalName(i_name, num.ToBig(it2.Index()))
1235
1236 # increment index before handling continue, etc.
1237 it2.Next()
1238
1239 try:
1240 status = self._Execute(node.body) # last one wins
1241 except vm.IntControlFlow as e:
1242 status = 0
1243 action = e.HandleLoop()
1244 if action == flow_e.Break:
1245 break
1246 elif action == flow_e.Raise:
1247 raise
1248
1249 return status
1250
1251 def _DoForExpr(self, node):
1252 # type: (command.ForExpr) -> int
1253
1254 status = 0
1255
1256 init = node.init
1257 for_cond = node.cond
1258 body = node.body
1259 update = node.update
1260
1261 self.arith_ev.Eval(init)
1262 with ctx_LoopLevel(self):
1263 while True:
1264 # We only accept integers as conditions
1265 cond_int = self.arith_ev.EvalToBigInt(for_cond)
1266 if mops.Equal(cond_int, mops.ZERO): # false
1267 break
1268
1269 try:
1270 status = self._Execute(body)
1271 except vm.IntControlFlow as e:
1272 status = 0
1273 action = e.HandleLoop()
1274 if action == flow_e.Break:
1275 break
1276 elif action == flow_e.Raise:
1277 raise
1278
1279 self.arith_ev.Eval(update)
1280
1281 return status
1282
1283 def _DoShFunction(self, node):
1284 # type: (command.ShFunction) -> None
1285 if node.name in self.procs and not self.exec_opts.redefine_proc_func():
1286 e_die(
1287 "Function %s was already defined (redefine_proc_func)" %
1288 node.name, node.name_tok)
1289 self.procs[node.name] = value.Proc(node.name, node.name_tok,
1290 proc_sig.Open, node.body, None,
1291 True)
1292
1293 def _DoProc(self, node):
1294 # type: (Proc) -> None
1295 proc_name = lexer.TokenVal(node.name)
1296 if proc_name in self.procs and not self.exec_opts.redefine_proc_func():
1297 e_die(
1298 "Proc %s was already defined (redefine_proc_func)" % proc_name,
1299 node.name)
1300
1301 if node.sig.tag() == proc_sig_e.Closed:
1302 sig = cast(proc_sig.Closed, node.sig)
1303 proc_defaults = func_proc.EvalProcDefaults(self.expr_ev, sig)
1304 else:
1305 proc_defaults = None
1306
1307 # no dynamic scope
1308 self.procs[proc_name] = value.Proc(proc_name, node.name, node.sig,
1309 node.body, proc_defaults, False)
1310
1311 def _DoFunc(self, node):
1312 # type: (Func) -> None
1313 name = lexer.TokenVal(node.name)
1314 lval = location.LName(name)
1315
1316 # Check that we haven't already defined a function
1317 cell = self.mem.GetCell(name, scope_e.LocalOnly)
1318 if cell and cell.val.tag() == value_e.Func:
1319 if self.exec_opts.redefine_proc_func():
1320 cell.readonly = False # Ensure we can unset the value
1321 did_unset = self.mem.Unset(lval, scope_e.LocalOnly)
1322 assert did_unset, name
1323 else:
1324 e_die(
1325 "Func %s was already defined (redefine_proc_func)" % name,
1326 node.name)
1327
1328 pos_defaults, named_defaults = func_proc.EvalFuncDefaults(
1329 self.expr_ev, node)
1330 func_val = value.Func(name, node, pos_defaults, named_defaults, None)
1331
1332 self.mem.SetNamed(lval,
1333 func_val,
1334 scope_e.LocalOnly,
1335 flags=state.SetReadOnly)
1336
1337 def _DoIf(self, node):
1338 # type: (command.If) -> int
1339 status = -1
1340
1341 done = False
1342 for if_arm in node.arms:
1343 b = self._EvalCondition(if_arm.cond, if_arm.keyword)
1344 if b:
1345 status = self._ExecuteList(if_arm.action)
1346 done = True
1347 break
1348
1349 if not done and node.else_action is not None:
1350 status = self._ExecuteList(node.else_action)
1351
1352 assert status != -1, 'Should have been initialized'
1353 return status
1354
1355 def _DoCase(self, node):
1356 # type: (command.Case) -> int
1357
1358 to_match = self._EvalCaseArg(node.to_match, node.case_kw)
1359 fnmatch_flags = FNM_CASEFOLD if self.exec_opts.nocasematch() else 0
1360
1361 status = 0 # If there are no arms, it should be zero?
1362
1363 done = False # Should we try the next arm?
1364
1365 # For &; terminator - not just case fallthrough, but IGNORE the condition!
1366 ignore_next_cond = False
1367
1368 for case_arm in node.arms:
1369 with tagswitch(case_arm.pattern) as case:
1370 if case(pat_e.Words):
1371 if to_match.tag() != value_e.Str:
1372 continue # A non-string `to_match` will never match a pat.Words
1373 to_match_str = cast(value.Str, to_match)
1374
1375 pat_words = cast(pat.Words, case_arm.pattern)
1376
1377 this_arm_matches = False
1378 if ignore_next_cond: # Special handling for ;&
1379 this_arm_matches = True
1380 ignore_next_cond = False
1381 else:
1382 for pat_word in pat_words.words:
1383 word_val = self.word_ev.EvalWordToString(
1384 pat_word, word_eval.QUOTE_FNMATCH)
1385
1386 if libc.fnmatch(word_val.s, to_match_str.s,
1387 fnmatch_flags):
1388 this_arm_matches = True
1389 break # Stop at first pattern
1390
1391 if this_arm_matches:
1392 status = self._ExecuteList(case_arm.action)
1393 done = True
1394
1395 # ;& and ;;& only apply to shell-style case
1396 if case_arm.right:
1397 id_ = case_arm.right.id
1398 if id_ == Id.Op_SemiAmp:
1399 # very weird semantic
1400 ignore_next_cond = True
1401 done = False
1402 elif id_ == Id.Op_DSemiAmp:
1403 # Keep going until next pattern
1404 done = False
1405
1406 elif case(pat_e.YshExprs):
1407 pat_exprs = cast(pat.YshExprs, case_arm.pattern)
1408
1409 for pat_expr in pat_exprs.exprs:
1410 expr_val = self.expr_ev.EvalExpr(
1411 pat_expr, case_arm.left)
1412
1413 if val_ops.ExactlyEqual(expr_val, to_match,
1414 case_arm.left):
1415 status = self._ExecuteList(case_arm.action)
1416 done = True
1417 break
1418
1419 elif case(pat_e.Eggex):
1420 eggex = cast(Eggex, case_arm.pattern)
1421 eggex_val = self.expr_ev.EvalEggex(eggex)
1422
1423 if val_ops.MatchRegex(to_match, eggex_val, self.mem):
1424 status = self._ExecuteList(case_arm.action)
1425 done = True
1426 break
1427
1428 elif case(pat_e.Else):
1429 status = self._ExecuteList(case_arm.action)
1430 done = True
1431 break
1432
1433 else:
1434 raise AssertionError()
1435
1436 if done: # first match wins
1437 break
1438
1439 return status
1440
1441 def _DoTimeBlock(self, node):
1442 # type: (command.TimeBlock) -> int
1443 # TODO:
1444 # - When do we need RUSAGE_CHILDREN?
1445 # - Respect TIMEFORMAT environment variable.
1446 # "If this variable is not set, Bash acts as if it had the value"
1447 # $'\nreal\t%3lR\nuser\t%3lU\nsys\t%3lS'
1448 # "A trailing newline is added when the format string is displayed."
1449
1450 s_real, s_user, s_sys = pyos.Time()
1451 status = self._Execute(node.pipeline)
1452 e_real, e_user, e_sys = pyos.Time()
1453 # note: mycpp doesn't support %.3f
1454 libc.print_time(e_real - s_real, e_user - s_user, e_sys - s_sys)
1455
1456 return status
1457
1458 def _DoRedirect(self, node, cmd_st):
1459 # type: (command.Redirect, CommandStatus) -> int
1460
1461 status = 0
1462 redirects = [] # type: List[RedirValue]
1463
1464 try:
1465 for redir in node.redirects:
1466 redirects.append(self._EvalRedirect(redir))
1467 except error.RedirectEval as e:
1468 self.errfmt.PrettyPrintError(e)
1469 redirects = None
1470 except error.FailGlob as e: # e.g. echo hi > foo-*
1471 if not e.HasLocation():
1472 e.location = self.mem.GetFallbackLocation()
1473 self.errfmt.PrettyPrintError(e, prefix='failglob: ')
1474 redirects = None
1475
1476 if redirects is None:
1477 # Error evaluating redirect words
1478 status = 1
1479
1480 # Translation fix: redirect I/O errors may happen in a C++
1481 # destructor ~vm::ctx_Redirect, which means they must be signaled
1482 # by out params, not exceptions.
1483 io_errors = [] # type: List[error.IOError_OSError]
1484
1485 # If we evaluated redirects, apply/push them
1486 if status == 0:
1487 self.shell_ex.PushRedirects(redirects, io_errors)
1488 if len(io_errors):
1489 # core/process.py prints cryptic errors, so we repeat them
1490 # here. e.g. Bad File Descriptor
1491 self.errfmt.PrintMessage(
1492 'I/O error applying redirect: %s' %
1493 pyutil.strerror(io_errors[0]),
1494 self.mem.GetFallbackLocation())
1495 status = 1
1496
1497 # If we applied redirects successfully, run the command_t, and pop
1498 # them.
1499 if status == 0:
1500 with vm.ctx_Redirect(self.shell_ex, len(redirects), io_errors):
1501 status = self._Execute(node.child)
1502 if len(io_errors):
1503 # It would be better to point to the right redirect
1504 # operator, but we don't track it specifically
1505 e_die("Fatal error popping redirect: %s" %
1506 pyutil.strerror(io_errors[0]))
1507
1508 return status
1509
1510 def _Dispatch(self, node, cmd_st):
1511 # type: (command_t, CommandStatus) -> int
1512 """Switch on the command_t variants and execute them."""
1513
1514 # If we call RunCommandSub in a recursive call to the executor, this will
1515 # be set true (if strict_errexit is false). But it only lasts for one
1516 # command.
1517 probe('cmd_eval', '_Dispatch', node.tag())
1518 self.check_command_sub_status = False
1519
1520 UP_node = node
1521 with tagswitch(node) as case:
1522 if case(command_e.Simple): # LEAF command
1523 node = cast(command.Simple, UP_node)
1524
1525 # for $LINENO, e.g. PS4='+$SOURCE_NAME:$LINENO:'
1526 # Note that for '> $LINENO' the location token is set in _EvalRedirect.
1527 # TODO: blame_tok should always be set.
1528 if node.blame_tok is not None:
1529 self.mem.SetTokenForLine(node.blame_tok)
1530
1531 self._MaybeRunDebugTrap()
1532 cmd_st.check_errexit = True
1533 status = self._DoSimple(node, cmd_st)
1534
1535 elif case(command_e.ExpandedAlias):
1536 node = cast(command.ExpandedAlias, UP_node)
1537 status = self._DoExpandedAlias(node)
1538
1539 elif case(command_e.Sentence):
1540 node = cast(command.Sentence, UP_node)
1541
1542 # Don't check_errexit since this isn't a leaf command
1543 if node.terminator.id == Id.Op_Semi:
1544 status = self._Execute(node.child)
1545 else:
1546 status = self.shell_ex.RunBackgroundJob(node.child)
1547
1548 elif case(command_e.Redirect):
1549 node = cast(command.Redirect, UP_node)
1550
1551 # set -e affects redirect error, like mksh and bash 5.2, but unlike
1552 # dash/ash
1553 cmd_st.check_errexit = True
1554 status = self._DoRedirect(node, cmd_st)
1555
1556 elif case(command_e.Pipeline):
1557 node = cast(command.Pipeline, UP_node)
1558 status = self._DoPipeline(node, cmd_st)
1559
1560 elif case(command_e.Subshell):
1561 node = cast(command.Subshell, UP_node)
1562
1563 # This is a leaf from the parent process POV
1564 cmd_st.check_errexit = True
1565 status = self.shell_ex.RunSubshell(node.child)
1566
1567 elif case(command_e.DBracket): # LEAF command
1568 node = cast(command.DBracket, UP_node)
1569
1570 self.mem.SetTokenForLine(node.left)
1571 self._MaybeRunDebugTrap()
1572
1573 self.tracer.PrintSourceCode(node.left, node.right, self.arena)
1574
1575 cmd_st.check_errexit = True
1576 cmd_st.show_code = True # this is a "leaf" for errors
1577 result = self.bool_ev.EvalB(node.expr)
1578 status = 0 if result else 1
1579
1580 elif case(command_e.DParen): # LEAF command
1581 node = cast(command.DParen, UP_node)
1582
1583 self.mem.SetTokenForLine(node.left)
1584 self._MaybeRunDebugTrap()
1585
1586 self.tracer.PrintSourceCode(node.left, node.right, self.arena)
1587
1588 cmd_st.check_errexit = True
1589 cmd_st.show_code = True # this is a "leaf" for errors
1590 i = self.arith_ev.EvalToBigInt(node.child)
1591 status = 1 if mops.Equal(i, mops.ZERO) else 0
1592
1593 elif case(command_e.ControlFlow): # LEAF command
1594 node = cast(command.ControlFlow, UP_node)
1595
1596 self.mem.SetTokenForLine(node.keyword)
1597 self._MaybeRunDebugTrap()
1598
1599 status = self._DoControlFlow(node)
1600
1601 elif case(command_e.VarDecl): # LEAF command
1602 node = cast(command.VarDecl, UP_node)
1603
1604 # Point to var name (bare assignment has no keyword)
1605 self.mem.SetTokenForLine(node.lhs[0].left)
1606 status = self._DoVarDecl(node)
1607
1608 elif case(command_e.Mutation): # LEAF command
1609 node = cast(command.Mutation, UP_node)
1610
1611 self.mem.SetTokenForLine(node.keyword) # point to setvar/set
1612 self._DoMutation(node)
1613 status = 0 # if no exception is thrown, it succeeds
1614
1615 elif case(command_e.ShAssignment): # LEAF command
1616 node = cast(command.ShAssignment, UP_node)
1617
1618 self.mem.SetTokenForLine(node.pairs[0].left)
1619 self._MaybeRunDebugTrap()
1620
1621 # Only unqualified assignment a=b
1622 status = self._DoShAssignment(node, cmd_st)
1623
1624 elif case(command_e.Expr): # YSH LEAF command
1625 node = cast(command.Expr, UP_node)
1626
1627 self.mem.SetTokenForLine(node.keyword)
1628 # YSH debug trap?
1629
1630 status = self._DoExpr(node)
1631
1632 elif case(command_e.Retval): # YSH LEAF command
1633 node = cast(command.Retval, UP_node)
1634
1635 self.mem.SetTokenForLine(node.keyword)
1636 # YSH debug trap? I think we don't want the debug trap in func
1637 # dialect, for speed?
1638
1639 val = self.expr_ev.EvalExpr(node.val, node.keyword)
1640 raise vm.ValueControlFlow(node.keyword, val)
1641
1642 # Note CommandList and DoGroup have no redirects, but BraceGroup does.
1643 # DoGroup has 'do' and 'done' spids for translation.
1644 elif case(command_e.CommandList):
1645 node = cast(command.CommandList, UP_node)
1646 status = self._ExecuteList(node.children)
1647
1648 elif case(command_e.DoGroup):
1649 node = cast(command.DoGroup, UP_node)
1650 status = self._ExecuteList(node.children)
1651
1652 elif case(command_e.BraceGroup):
1653 node = cast(BraceGroup, UP_node)
1654 status = self._ExecuteList(node.children)
1655
1656 elif case(command_e.AndOr):
1657 node = cast(command.AndOr, UP_node)
1658 status = self._DoAndOr(node, cmd_st)
1659
1660 elif case(command_e.WhileUntil):
1661 node = cast(command.WhileUntil, UP_node)
1662
1663 self.mem.SetTokenForLine(node.keyword)
1664 status = self._DoWhileUntil(node)
1665
1666 elif case(command_e.ForEach):
1667 node = cast(command.ForEach, UP_node)
1668
1669 self.mem.SetTokenForLine(node.keyword)
1670 status = self._DoForEach(node)
1671
1672 elif case(command_e.ForExpr):
1673 node = cast(command.ForExpr, UP_node)
1674
1675 self.mem.SetTokenForLine(node.keyword) # for x in $LINENO
1676 status = self._DoForExpr(node)
1677
1678 elif case(command_e.ShFunction):
1679 node = cast(command.ShFunction, UP_node)
1680 self._DoShFunction(node)
1681 status = 0
1682
1683 elif case(command_e.Proc):
1684 node = cast(Proc, UP_node)
1685 self._DoProc(node)
1686 status = 0
1687
1688 elif case(command_e.Func):
1689 node = cast(Func, UP_node)
1690
1691 # Needed for error, when the func is an existing variable name
1692 self.mem.SetTokenForLine(node.name)
1693
1694 self._DoFunc(node)
1695 status = 0
1696
1697 elif case(command_e.If):
1698 node = cast(command.If, UP_node)
1699
1700 # No SetTokenForLine() because
1701 # - $LINENO can't appear directly in 'if'
1702 # - 'if' doesn't directly cause errors
1703 # It will be taken care of by command.Simple, condition, etc.
1704 status = self._DoIf(node)
1705
1706 elif case(command_e.NoOp):
1707 status = 0 # make it true
1708
1709 elif case(command_e.Case):
1710 node = cast(command.Case, UP_node)
1711
1712 # Must set location for 'case $LINENO'
1713 self.mem.SetTokenForLine(node.case_kw)
1714 self._MaybeRunDebugTrap()
1715 status = self._DoCase(node)
1716
1717 elif case(command_e.TimeBlock):
1718 node = cast(command.TimeBlock, UP_node)
1719 status = self._DoTimeBlock(node)
1720
1721 else:
1722 raise NotImplementedError(node.tag())
1723
1724 # Return to caller. Note the only case that didn't set it was Pipeline,
1725 # which set cmd_st.pipe_status.
1726 return status
1727
1728 def RunPendingTraps(self):
1729 # type: () -> None
1730
1731 trap_nodes = self.trap_state.GetPendingTraps()
1732 if trap_nodes is not None:
1733 with state.ctx_Option(self.mutable_opts, [option_i._running_trap],
1734 True):
1735 for trap_node in trap_nodes:
1736 # Isolate the exit status.
1737 with state.ctx_Registers(self.mem):
1738 # Trace it. TODO: Show the trap kind too
1739 with dev.ctx_Tracer(self.tracer, 'trap', None):
1740 self._Execute(trap_node)
1741
1742 def _Execute(self, node):
1743 # type: (command_t) -> int
1744 """Call _Dispatch(), and performs the errexit check.
1745
1746 Also runs trap handlers.
1747 """
1748 # TODO: Do this in "leaf" nodes? SimpleCommand, DBracket, DParen should
1749 # call self.DoTick()? That will RunPendingTraps and check the Ctrl-C flag,
1750 # and maybe throw an exception.
1751 self.RunPendingTraps()
1752
1753 # We only need this somewhat hacky check in osh-cpp since python's runtime
1754 # handles SIGINT for us in osh.
1755 if mylib.CPP:
1756 if self.signal_safe.PollSigInt():
1757 raise KeyboardInterrupt()
1758
1759 # Manual GC point before every statement
1760 mylib.MaybeCollect()
1761
1762 # Optimization: These 2 records have rarely-used lists, so we don't pass
1763 # alloc_lists=True. We create them on demand.
1764 cmd_st = CommandStatus.CreateNull()
1765 if len(self.status_array_pool):
1766 # Optimized to avoid allocs
1767 process_sub_st = self.status_array_pool.pop()
1768 else:
1769 process_sub_st = StatusArray.CreateNull()
1770
1771 with vm.ctx_ProcessSub(self.shell_ex, process_sub_st): # for wait()
1772 try:
1773 status = self._Dispatch(node, cmd_st)
1774 except error.FailGlob as e:
1775 if not e.HasLocation(): # Last resort!
1776 e.location = self.mem.GetFallbackLocation()
1777 self.errfmt.PrettyPrintError(e, prefix='failglob: ')
1778 status = 1 # another redirect word eval error
1779 cmd_st.check_errexit = True # failglob + errexit
1780
1781 # Now we've waited for process subs
1782
1783 # If it was a real pipeline, compute status from ${PIPESTATUS[@]} aka
1784 # @_pipeline_status
1785 pipe_status = cmd_st.pipe_status
1786 # Note: bash/mksh set PIPESTATUS set even on non-pipelines. This
1787 # makes it annoying to check both _process_sub_status and
1788 # _pipeline_status
1789
1790 errexit_loc = loc.Missing # type: loc_t
1791 if pipe_status is not None:
1792 # Tricky: _DoPipeline sets cmt_st.pipe_status and returns -1
1793 # for a REAL pipeline (but not singleton pipelines)
1794 assert status == -1, (
1795 "Shouldn't have redir errors when PIPESTATUS (status = %d)" %
1796 status)
1797
1798 self.mem.SetPipeStatus(pipe_status)
1799
1800 if self.exec_opts.pipefail():
1801 # The status is that of the last command that is non-zero.
1802 status = 0
1803 for i, st in enumerate(pipe_status):
1804 if st != 0:
1805 status = st
1806 errexit_loc = cmd_st.pipe_locs[i]
1807 else:
1808 # The status is that of last command, period.
1809 status = pipe_status[-1]
1810
1811 if cmd_st.pipe_negated:
1812 status = 1 if status == 0 else 0
1813
1814 # Compute status from _process_sub_status
1815 if process_sub_st.codes is None:
1816 # Optimized to avoid allocs
1817 self.status_array_pool.append(process_sub_st)
1818 else:
1819 codes = process_sub_st.codes
1820 self.mem.SetProcessSubStatus(codes)
1821 if status == 0 and self.exec_opts.process_sub_fail():
1822 # Choose the LAST non-zero status, consistent with pipefail above.
1823 for i, st in enumerate(codes):
1824 if st != 0:
1825 status = st
1826 errexit_loc = process_sub_st.locs[i]
1827
1828 self.mem.SetLastStatus(status)
1829
1830 # NOTE: Bash says that 'set -e' checking is done after each 'pipeline'.
1831 # However, any bash construct can appear in a pipeline. So it's easier
1832 # just to put it at the end, instead of after every node.
1833 #
1834 # Possible exceptions:
1835 # - function def (however this always exits 0 anyway)
1836 # - assignment - its result should be the result of the RHS?
1837 # - e.g. arith sub, command sub? I don't want arith sub.
1838 # - ControlFlow: always raises, it has no status.
1839 if cmd_st.check_errexit:
1840 #log('cmd_st %s', cmd_st)
1841 self._CheckStatus(status, cmd_st, node, errexit_loc)
1842
1843 return status
1844
1845 def _ExecuteList(self, children):
1846 # type: (List[command_t]) -> int
1847 status = 0 # for empty list
1848 for child in children:
1849 # last status wins
1850 status = self._Execute(child)
1851 return status
1852
1853 def LastStatus(self):
1854 # type: () -> int
1855 """For main_loop.py to determine the exit code of the shell itself."""
1856 return self.mem.LastStatus()
1857
1858 def _NoForkLast(self, node):
1859 # type: (command_t) -> None
1860
1861 if 0:
1862 log('optimizing')
1863 node.PrettyPrint(sys.stderr)
1864 log('')
1865
1866 UP_node = node
1867 with tagswitch(node) as case:
1868 if case(command_e.Simple):
1869 node = cast(command.Simple, UP_node)
1870 node.do_fork = False
1871 if 0:
1872 log('Simple optimized')
1873
1874 elif case(command_e.Pipeline):
1875 node = cast(command.Pipeline, UP_node)
1876 if node.negated is None:
1877 #log ('pipe')
1878 self._NoForkLast(node.children[-1])
1879
1880 elif case(command_e.Sentence):
1881 node = cast(command.Sentence, UP_node)
1882 self._NoForkLast(node.child)
1883
1884 elif case(command_e.CommandList):
1885 # Subshells start with CommandList, even if there's only one.
1886 node = cast(command.CommandList, UP_node)
1887 self._NoForkLast(node.children[-1])
1888
1889 elif case(command_e.BraceGroup):
1890 # TODO: What about redirects?
1891 node = cast(BraceGroup, UP_node)
1892 self._NoForkLast(node.children[-1])
1893
1894 def _RemoveSubshells(self, node):
1895 # type: (command_t) -> command_t
1896 """Eliminate redundant subshells like ( echo hi ) | wc -l etc.
1897
1898 This is ONLY called at the top level of ExecuteAndCatch() - it wouldn't
1899 be correct otherwise.
1900 """
1901 UP_node = node
1902 with tagswitch(node) as case:
1903 if case(command_e.Subshell):
1904 node = cast(command.Subshell, UP_node)
1905 # Optimize ( ( date ) ) etc.
1906 return self._RemoveSubshells(node.child)
1907 return node
1908
1909 def ExecuteAndCatch(self, node, cmd_flags=0):
1910 # type: (command_t, int) -> Tuple[bool, bool]
1911 """Execute a subprogram, handling vm.IntControlFlow and fatal exceptions.
1912
1913 Args:
1914 node: LST subtree
1915 optimize: Whether to exec the last process rather than fork/exec
1916
1917 Returns:
1918 TODO: use enum 'why' instead of the 2 booleans
1919
1920 Used by
1921 - main_loop.py.
1922 - SubProgramThunk for pipelines, subshell, command sub, process sub
1923 - TODO: Signals besides EXIT trap
1924
1925 Note: To do what optimize does, dash has EV_EXIT flag and yash has a
1926 finally_exit boolean. We use a different algorithm.
1927 """
1928 if cmd_flags & Optimize:
1929 node = self._RemoveSubshells(node)
1930 self._NoForkLast(node) # turn the last ones into exec
1931
1932 if 0:
1933 log('after opt:')
1934 node.PrettyPrint()
1935 log('')
1936
1937 is_return = False
1938 is_fatal = False
1939 is_errexit = False
1940
1941 err = None # type: error.FatalRuntime
1942 status = -1 # uninitialized
1943
1944 try:
1945 options = [] # type: List[int]
1946 if cmd_flags & NoDebugTrap:
1947 options.append(option_i._no_debug_trap)
1948 if cmd_flags & NoErrTrap:
1949 options.append(option_i._no_err_trap)
1950 with state.ctx_Option(self.mutable_opts, options, True):
1951 status = self._Execute(node)
1952 except vm.IntControlFlow as e:
1953 if cmd_flags & RaiseControlFlow:
1954 raise # 'eval break' and 'source return.sh', etc.
1955 else:
1956 # Return at top level is OK, unlike in bash.
1957 if e.IsReturn():
1958 is_return = True
1959 status = e.StatusCode()
1960 else:
1961 # TODO: This error message is invalid. Can also happen in eval.
1962 # We need a flag.
1963
1964 # Invalid control flow
1965 self.errfmt.Print_(
1966 "Loop and control flow can't be in different processes",
1967 blame_loc=e.token)
1968 is_fatal = True
1969 # All shells exit 0 here. It could be hidden behind
1970 # strict_control_flow if the incompatibility causes problems.
1971 status = 1
1972 except error.Parse as e:
1973 self.dumper.MaybeRecord(self, e) # Do this before unwinding stack
1974 raise
1975 except error.ErrExit as e:
1976 err = e
1977 is_errexit = True
1978 except error.FatalRuntime as e:
1979 err = e
1980
1981 if err:
1982 status = err.ExitStatus()
1983
1984 is_fatal = True
1985 # Do this before unwinding stack
1986 self.dumper.MaybeRecord(self, err)
1987
1988 if not err.HasLocation(): # Last resort!
1989 #log('Missing location')
1990 err.location = self.mem.GetFallbackLocation()
1991 #log('%s', err.location)
1992
1993 if is_errexit:
1994 if self.exec_opts.verbose_errexit():
1995 self.errfmt.PrintErrExit(cast(error.ErrExit, err),
1996 posix.getpid())
1997 else:
1998 self.errfmt.PrettyPrintError(err, prefix='fatal: ')
1999
2000 assert status >= 0, 'Should have been initialized'
2001
2002 # Problem: We have no idea here if a SUBSHELL (or pipeline comment) already
2003 # created a crash dump. So we get 2 or more of them.
2004 self.dumper.MaybeDump(status)
2005
2006 self.mem.SetLastStatus(status)
2007 return is_return, is_fatal
2008
2009 def EvalCommand(self, block):
2010 # type: (command_t) -> int
2011 """For builtins to evaluate command args.
2012
2013 e.g. cd /tmp (x)
2014 """
2015 status = 0
2016 try:
2017 status = self._Execute(block) # can raise FatalRuntimeError, etc.
2018 except vm.IntControlFlow as e: # A block is more like a function.
2019 # return in a block
2020 if e.IsReturn():
2021 status = e.StatusCode()
2022 else:
2023 e_die('Unexpected control flow in block', e.token)
2024
2025 return status
2026
2027 def MaybeRunExitTrap(self, mut_status):
2028 # type: (IntParamBox) -> None
2029 """If an EXIT trap handler exists, run it.
2030
2031 Only mutates the status if 'return' or 'exit'. This is odd behavior, but
2032 all bash/dash/mksh seem to agree on it. See cases in
2033 builtin-trap.test.sh.
2034
2035 Note: if we could easily modulo -1 % 256 == 255 here, then we could get rid
2036 of this awkward interface. But that's true in Python and not C!
2037
2038 Could use i & (n-1) == i & 255 because we have a power of 2.
2039 https://stackoverflow.com/questions/14997165/fastest-way-to-get-a-positive-modulo-in-c-c
2040 """
2041 node = self.trap_state.GetHook('EXIT') # type: command_t
2042 if node:
2043 # NOTE: Don't set option_i._running_trap, because that's for
2044 # RunPendingTraps() in the MAIN LOOP
2045 with dev.ctx_Tracer(self.tracer, 'trap EXIT', None):
2046 try:
2047 is_return, is_fatal = self.ExecuteAndCatch(node)
2048 except util.UserExit as e: # explicit exit
2049 mut_status.i = e.status
2050 return
2051 if is_return: # explicit 'return' in the trap handler!
2052 mut_status.i = self.LastStatus()
2053
2054 def _MaybeRunDebugTrap(self):
2055 # type: () -> None
2056 """Run user-specified DEBUG code before certain commands."""
2057 node = self.trap_state.GetHook('DEBUG') # type: command_t
2058 if node is None:
2059 return
2060
2061 # Fix lastpipe / job control / DEBUG trap interaction
2062 if self.exec_opts._no_debug_trap():
2063 return
2064
2065 # Don't run recursively run traps, etc.
2066 if not self.mem.ShouldRunDebugTrap():
2067 return
2068
2069 # NOTE: Don't set option_i._running_trap, because that's for
2070 # RunPendingTraps() in the MAIN LOOP
2071
2072 with dev.ctx_Tracer(self.tracer, 'trap DEBUG', None):
2073 with state.ctx_Registers(self.mem): # prevent setting $? etc.
2074 # for SetTokenForLine $LINENO
2075 with state.ctx_DebugTrap(self.mem):
2076 # Don't catch util.UserExit, etc.
2077 self._Execute(node)
2078
2079 def _MaybeRunErrTrap(self):
2080 # type: () -> None
2081 """
2082 Run user-specified ERR code after checking the status of certain
2083 commands (pipelines)
2084 """
2085 node = self.trap_state.GetHook('ERR') # type: command_t
2086 if node is None:
2087 return
2088
2089 # ERR trap is only run for a whole pipeline, not its parts
2090 if self.exec_opts._no_err_trap():
2091 return
2092
2093 # Prevent infinite recursion
2094 if self.mem.running_err_trap:
2095 return
2096
2097 # "disabled errexit" rule
2098 if self.mutable_opts.ErrExitIsDisabled():
2099 return
2100
2101 # bash rule - affected by set -o errtrace
2102 if self.mem.InsideFunction():
2103 return
2104
2105 # NOTE: Don't set option_i._running_trap, because that's for
2106 # RunPendingTraps() in the MAIN LOOP
2107
2108 with dev.ctx_Tracer(self.tracer, 'trap ERR', None):
2109 #with state.ctx_Registers(self.mem): # prevent setting $? etc.
2110 with state.ctx_ErrTrap(self.mem):
2111 self._Execute(node)
2112
2113 def RunProc(self, proc, cmd_val):
2114 # type: (value.Proc, cmd_value.Argv) -> int
2115 """Run procs aka "shell functions".
2116
2117 For SimpleCommand and registered completion hooks.
2118 """
2119 sig = proc.sig
2120 if sig.tag() == proc_sig_e.Closed:
2121 # We're binding named params. User should use @rest. No 'shift'.
2122 proc_argv = [] # type: List[str]
2123 else:
2124 proc_argv = cmd_val.argv[1:]
2125
2126 # Hm this sets "$@". TODO: Set ARGV only
2127 with state.ctx_ProcCall(self.mem, self.mutable_opts, proc, proc_argv):
2128 func_proc.BindProcArgs(proc, cmd_val, self.mem)
2129
2130 # Redirects still valid for functions.
2131 # Here doc causes a pipe and Process(SubProgramThunk).
2132 try:
2133 status = self._Execute(proc.body)
2134 except vm.IntControlFlow as e:
2135 if e.IsReturn():
2136 status = e.StatusCode()
2137 else:
2138 # break/continue used in the wrong place.
2139 e_die(
2140 'Unexpected %r (in proc call)' %
2141 lexer.TokenVal(e.token), e.token)
2142 except error.FatalRuntime as e:
2143 # Dump the stack before unwinding it
2144 self.dumper.MaybeRecord(self, e)
2145 raise
2146
2147 return status
2148
2149 def RunFuncForCompletion(self, proc, argv):
2150 # type: (value.Proc, List[str]) -> int
2151 """
2152 Args:
2153 argv: $1 $2 $3 ... not including $0
2154 """
2155 cmd_val = MakeBuiltinArgv(argv)
2156
2157 # TODO: Change this to run YSH procs and funcs too
2158 try:
2159 status = self.RunProc(proc, cmd_val)
2160 except error.FatalRuntime as e:
2161 self.errfmt.PrettyPrintError(e)
2162 status = e.ExitStatus()
2163 except vm.IntControlFlow as e:
2164 # shouldn't be able to exit the shell from a completion hook!
2165 # TODO: Avoid overwriting the prompt!
2166 self.errfmt.Print_('Attempted to exit from completion hook.',
2167 blame_loc=e.token)
2168
2169 status = 1
2170 # NOTE: (IOError, OSError) are caught in completion.py:ReadlineCallback
2171 return status
2172
2173
2174# vim: sw=4