| 1 | # Copyright 2016 Andy Chu. All rights reserved.
|
| 2 | # Licensed under the Apache License, Version 2.0 (the "License");
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| 3 | # you may not use this file except in compliance with the License.
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| 4 | # You may obtain a copy of the License at
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| 5 | #
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| 6 | # http://www.apache.org/licenses/LICENSE-2.0
|
| 7 | """process.py - Launch processes and manipulate file descriptors."""
|
| 8 | from __future__ import print_function
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| 9 |
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| 10 | from errno import EACCES, EBADF, ECHILD, EINTR, ENOENT, ENOEXEC, EEXIST
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| 11 | import fcntl as fcntl_
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| 12 | from fcntl import F_DUPFD, F_GETFD, F_SETFD, FD_CLOEXEC
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| 13 | from signal import (SIG_DFL, SIG_IGN, SIGINT, SIGPIPE, SIGQUIT, SIGTSTP,
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| 14 | SIGTTOU, SIGTTIN, SIGWINCH)
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| 15 |
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| 16 | import libc
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| 17 |
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| 18 | from _devbuild.gen.id_kind_asdl import Id
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| 19 | from _devbuild.gen.runtime_asdl import (job_state_e, job_state_t,
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| 20 | job_state_str, wait_status,
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| 21 | wait_status_t, RedirValue,
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| 22 | redirect_arg, redirect_arg_e, trace,
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| 23 | trace_t)
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| 24 | from _devbuild.gen.syntax_asdl import (
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| 25 | loc_t,
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| 26 | redir_loc,
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| 27 | redir_loc_e,
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| 28 | redir_loc_t,
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| 29 | )
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| 30 | from _devbuild.gen.value_asdl import (value, value_e)
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| 31 | from core import dev
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| 32 | from core import error
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| 33 | from core.error import e_die
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| 34 | from core import pyutil
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| 35 | from core import pyos
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| 36 | from core import state
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| 37 | from display import ui
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| 38 | from core import util
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| 39 | from data_lang import j8_lite
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| 40 | from frontend import location
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| 41 | from frontend import match
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| 42 | from mycpp import iolib
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| 43 | from mycpp import mylib
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| 44 | from mycpp.mylib import log, print_stderr, probe, tagswitch, iteritems
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| 45 |
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| 46 | import posix_ as posix
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| 47 | from posix_ import (
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| 48 | # translated by mycpp and directly called! No wrapper!
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| 49 | WIFSIGNALED,
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| 50 | WIFEXITED,
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| 51 | WIFSTOPPED,
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| 52 | WEXITSTATUS,
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| 53 | WSTOPSIG,
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| 54 | WTERMSIG,
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| 55 | WCOREDUMP,
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| 56 | WNOHANG,
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| 57 | O_APPEND,
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| 58 | O_CREAT,
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| 59 | O_EXCL,
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| 60 | O_NONBLOCK,
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| 61 | O_NOCTTY,
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| 62 | O_RDONLY,
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| 63 | O_RDWR,
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| 64 | O_WRONLY,
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| 65 | O_TRUNC,
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| 66 | F_DUPFD_CLOEXEC, # OSH patch - this didn't appear until Python 3.2
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| 67 | )
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| 68 |
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| 69 | from typing import IO, List, Tuple, Dict, Optional, Any, cast, TYPE_CHECKING
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| 70 |
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| 71 | if TYPE_CHECKING:
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| 72 | from _devbuild.gen.runtime_asdl import cmd_value
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| 73 | from _devbuild.gen.syntax_asdl import command_t
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| 74 | from builtin import trap_osh
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| 75 | from core import optview
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| 76 | from core import vm
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| 77 | from core.util import _DebugFile
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| 78 | from osh.cmd_eval import CommandEvaluator
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| 79 |
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| 80 | NO_FD = -1
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| 81 |
|
| 82 | # Minimum file descriptor that the shell can use. Other descriptors can be
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| 83 | # directly used by user programs, e.g. exec 9>&1
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| 84 | #
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| 85 | # Oils uses 100 because users are allowed TWO digits in frontend/lexer_def.py.
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| 86 | # This is a compromise between bash (unlimited, but requires crazy
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| 87 | # bookkeeping), and dash/zsh (10) and mksh (24)
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| 88 | _SHELL_MIN_FD = 100
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| 89 |
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| 90 | # Style for 'jobs' builtin
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| 91 | STYLE_DEFAULT = 0
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| 92 | STYLE_LONG = 1
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| 93 | STYLE_PID_ONLY = 2
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| 94 |
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| 95 | # To save on allocations in JobList::JobFromSpec()
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| 96 | CURRENT_JOB_SPECS = ['', '%', '%%', '%+']
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| 97 |
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| 98 |
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| 99 | class ctx_FileCloser(object):
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| 100 |
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| 101 | def __init__(self, f):
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| 102 | # type: (mylib.LineReader) -> None
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| 103 | self.f = f
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| 104 |
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| 105 | def __enter__(self):
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| 106 | # type: () -> None
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| 107 | pass
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| 108 |
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| 109 | def __exit__(self, type, value, traceback):
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| 110 | # type: (Any, Any, Any) -> None
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| 111 | self.f.close()
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| 112 |
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| 113 |
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| 114 | def InitInteractiveShell(signal_safe):
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| 115 | # type: (iolib.SignalSafe) -> None
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| 116 | """Called when initializing an interactive shell."""
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| 117 |
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| 118 | # The shell itself should ignore Ctrl-\.
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| 119 | iolib.sigaction(SIGQUIT, SIG_IGN)
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| 120 |
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| 121 | # This prevents Ctrl-Z from suspending OSH in interactive mode.
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| 122 | iolib.sigaction(SIGTSTP, SIG_IGN)
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| 123 |
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| 124 | # More signals from
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| 125 | # https://www.gnu.org/software/libc/manual/html_node/Initializing-the-Shell.html
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| 126 | # (but not SIGCHLD)
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| 127 | iolib.sigaction(SIGTTOU, SIG_IGN)
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| 128 | iolib.sigaction(SIGTTIN, SIG_IGN)
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| 129 |
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| 130 | # Register a callback to receive terminal width changes.
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| 131 | # NOTE: In line_input.c, we turned off rl_catch_sigwinch.
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| 132 |
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| 133 | # This is ALWAYS on, which means that it can cause EINTR, and wait() and
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| 134 | # read() have to handle it
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| 135 | iolib.RegisterSignalInterest(SIGWINCH)
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| 136 |
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| 137 |
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| 138 | _ = F_DUPFD_CLOEXEC # shut up lint for now
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| 139 |
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| 140 | def SaveFd(fd):
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| 141 | # type: (int) -> int
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| 142 |
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| 143 | # Note: may raise IOError_OSError
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| 144 | saved = fcntl_.fcntl(fd, F_DUPFD, _SHELL_MIN_FD) # type: int
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| 145 |
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| 146 | # Bug fix: make sure we never leak the saved descriptor to child processes
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| 147 | fcntl_.fcntl(saved, F_SETFD, FD_CLOEXEC)
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| 148 |
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| 149 | # TODO: use this
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| 150 | #saved = fcntl_.fcntl(fd, F_DUPFD_CLOEXEC, _SHELL_MIN_FD) # type: int
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| 151 |
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| 152 | return saved
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| 153 |
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| 154 |
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| 155 | class _RedirFrame(object):
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| 156 |
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| 157 | def __init__(self, saved_fd, orig_fd, forget):
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| 158 | # type: (int, int, bool) -> None
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| 159 | self.saved_fd = saved_fd
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| 160 | self.orig_fd = orig_fd
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| 161 | self.forget = forget
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| 162 |
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| 163 |
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| 164 | class _FdFrame(object):
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| 165 |
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| 166 | def __init__(self):
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| 167 | # type: () -> None
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| 168 | self.saved = [] # type: List[_RedirFrame]
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| 169 | self.need_wait = [] # type: List[Process]
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| 170 |
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| 171 | def Forget(self):
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| 172 | # type: () -> None
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| 173 | """For exec 1>&2."""
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| 174 | for rf in reversed(self.saved):
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| 175 | if rf.saved_fd != NO_FD and rf.forget:
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| 176 | posix.close(rf.saved_fd)
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| 177 |
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| 178 | del self.saved[:] # like list.clear() in Python 3.3
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| 179 | del self.need_wait[:]
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| 180 |
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| 181 | def __repr__(self):
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| 182 | # type: () -> str
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| 183 | return '<_FdFrame %s>' % self.saved
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| 184 |
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| 185 |
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| 186 | class FdState(object):
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| 187 | """File descriptor state for the current process.
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| 188 |
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| 189 | For example, you can do 'myfunc > out.txt' without forking. Child
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| 190 | processes inherit our state.
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| 191 | """
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| 192 |
|
| 193 | def __init__(
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| 194 | self,
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| 195 | errfmt, # type: ui.ErrorFormatter
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| 196 | job_control, # type: JobControl
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| 197 | job_list, # type: JobList
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| 198 | mem, # type: state.Mem
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| 199 | tracer, # type: Optional[dev.Tracer]
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| 200 | waiter, # type: Optional[Waiter]
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| 201 | exec_opts, # type: optview.Exec
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| 202 | ):
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| 203 | # type: (...) -> None
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| 204 | """
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| 205 | Args:
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| 206 | errfmt: for errors
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| 207 | job_list: For keeping track of _HereDocWriterThunk
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| 208 | """
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| 209 | self.errfmt = errfmt
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| 210 | self.job_control = job_control
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| 211 | self.job_list = job_list
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| 212 | self.cur_frame = _FdFrame() # for the top level
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| 213 | self.stack = [self.cur_frame]
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| 214 | self.mem = mem
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| 215 | self.tracer = tracer
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| 216 | self.waiter = waiter
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| 217 | self.exec_opts = exec_opts
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| 218 |
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| 219 | def Open(self, path):
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| 220 | # type: (str) -> mylib.LineReader
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| 221 | """Opens a path for read, but moves it out of the reserved 3-9 fd
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| 222 | range.
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| 223 |
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| 224 | Returns:
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| 225 | A Python file object. The caller is responsible for Close().
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| 226 |
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| 227 | Raises:
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| 228 | IOError or OSError if the path can't be found. (This is Python-induced wart)
|
| 229 | """
|
| 230 | fd_mode = O_RDONLY
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| 231 | f = self._Open(path, 'r', fd_mode)
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| 232 |
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| 233 | # Hacky downcast
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| 234 | return cast('mylib.LineReader', f)
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| 235 |
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| 236 | # used for util.DebugFile
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| 237 | def OpenForWrite(self, path):
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| 238 | # type: (str) -> mylib.Writer
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| 239 | fd_mode = O_CREAT | O_RDWR
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| 240 | f = self._Open(path, 'w', fd_mode)
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| 241 |
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| 242 | # Hacky downcast
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| 243 | return cast('mylib.Writer', f)
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| 244 |
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| 245 | def _Open(self, path, c_mode, fd_mode):
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| 246 | # type: (str, str, int) -> IO[str]
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| 247 | fd = posix.open(path, fd_mode, 0o666) # may raise OSError
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| 248 |
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| 249 | # Immediately move it to a new location
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| 250 | new_fd = SaveFd(fd)
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| 251 | posix.close(fd)
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| 252 |
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| 253 | # Return a Python file handle
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| 254 | f = posix.fdopen(new_fd, c_mode) # may raise IOError
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| 255 | return f
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| 256 |
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| 257 | def _WriteFdToMem(self, fd_name, fd):
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| 258 | # type: (str, int) -> None
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| 259 | if self.mem:
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| 260 | # setvar, not setref
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| 261 | state.OshLanguageSetValue(self.mem, location.LName(fd_name),
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| 262 | value.Str(str(fd)))
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| 263 |
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| 264 | def _ReadFdFromMem(self, fd_name):
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| 265 | # type: (str) -> int
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| 266 | val = self.mem.GetValue(fd_name)
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| 267 | if val.tag() == value_e.Str:
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| 268 | try:
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| 269 | return int(cast(value.Str, val).s)
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| 270 | except ValueError:
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| 271 | return NO_FD
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| 272 | return NO_FD
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| 273 |
|
| 274 | def _PushSave(self, fd):
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| 275 | # type: (int) -> bool
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| 276 | """Save fd to a new location and remember to restore it later."""
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| 277 | #log('---- _PushSave %s', fd)
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| 278 | ok = True
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| 279 | try:
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| 280 | new_fd = SaveFd(fd)
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| 281 | except (IOError, OSError) as e:
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| 282 | ok = False
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| 283 | # Example program that causes this error: exec 4>&1. Descriptor 4 isn't
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| 284 | # open.
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| 285 | # This seems to be ignored in dash too in savefd()?
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| 286 | if e.errno != EBADF:
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| 287 | raise
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| 288 | if ok:
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| 289 | posix.close(fd)
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| 290 | self.cur_frame.saved.append(_RedirFrame(new_fd, fd, True))
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| 291 | else:
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| 292 | # if we got EBADF, we still need to close the original on Pop()
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| 293 | self._PushClose(fd)
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| 294 |
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| 295 | return ok
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| 296 |
|
| 297 | def _PushDup(self, fd1, blame_loc):
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| 298 | # type: (int, redir_loc_t) -> int
|
| 299 | """Save fd2 in a higher range, and dup fd1 onto fd2.
|
| 300 |
|
| 301 | Returns whether F_DUPFD/dup2 succeeded, and the new descriptor.
|
| 302 | """
|
| 303 | UP_loc = blame_loc
|
| 304 | if blame_loc.tag() == redir_loc_e.VarName:
|
| 305 | fd2_name = cast(redir_loc.VarName, UP_loc).name
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| 306 | try:
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| 307 | # F_DUPFD: GREATER than range
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| 308 | new_fd = fcntl_.fcntl(fd1, F_DUPFD, _SHELL_MIN_FD) # type: int
|
| 309 | except (IOError, OSError) as e:
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| 310 | if e.errno == EBADF:
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| 311 | print_stderr('F_DUPFD fd %d: %s' %
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| 312 | (fd1, pyutil.strerror(e)))
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| 313 | return NO_FD
|
| 314 | else:
|
| 315 | raise # this redirect failed
|
| 316 |
|
| 317 | self._WriteFdToMem(fd2_name, new_fd)
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| 318 |
|
| 319 | elif blame_loc.tag() == redir_loc_e.Fd:
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| 320 | fd2 = cast(redir_loc.Fd, UP_loc).fd
|
| 321 |
|
| 322 | if fd1 == fd2:
|
| 323 | # The user could have asked for it to be open on descriptor 3, but open()
|
| 324 | # already returned 3, e.g. echo 3>out.txt
|
| 325 | return NO_FD
|
| 326 |
|
| 327 | # Check the validity of fd1 before _PushSave(fd2)
|
| 328 | try:
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| 329 | fcntl_.fcntl(fd1, F_GETFD)
|
| 330 | except (IOError, OSError) as e:
|
| 331 | print_stderr('F_GETFD fd %d: %s' % (fd1, pyutil.strerror(e)))
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| 332 | raise
|
| 333 |
|
| 334 | need_restore = self._PushSave(fd2)
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| 335 |
|
| 336 | #log('==== dup2 %s %s\n' % (fd1, fd2))
|
| 337 | try:
|
| 338 | posix.dup2(fd1, fd2)
|
| 339 | except (IOError, OSError) as e:
|
| 340 | # bash/dash give this error too, e.g. for 'echo hi 1>&3'
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| 341 | print_stderr('dup2(%d, %d): %s' %
|
| 342 | (fd1, fd2, pyutil.strerror(e)))
|
| 343 |
|
| 344 | # Restore and return error
|
| 345 | if need_restore:
|
| 346 | rf = self.cur_frame.saved.pop()
|
| 347 | posix.dup2(rf.saved_fd, rf.orig_fd)
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| 348 | posix.close(rf.saved_fd)
|
| 349 |
|
| 350 | raise # this redirect failed
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| 351 |
|
| 352 | new_fd = fd2
|
| 353 |
|
| 354 | else:
|
| 355 | raise AssertionError()
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| 356 |
|
| 357 | return new_fd
|
| 358 |
|
| 359 | def _PushCloseFd(self, blame_loc):
|
| 360 | # type: (redir_loc_t) -> bool
|
| 361 | """For 2>&-"""
|
| 362 | # exec {fd}>&- means close the named descriptor
|
| 363 |
|
| 364 | UP_loc = blame_loc
|
| 365 | if blame_loc.tag() == redir_loc_e.VarName:
|
| 366 | fd_name = cast(redir_loc.VarName, UP_loc).name
|
| 367 | fd = self._ReadFdFromMem(fd_name)
|
| 368 | if fd == NO_FD:
|
| 369 | return False
|
| 370 |
|
| 371 | elif blame_loc.tag() == redir_loc_e.Fd:
|
| 372 | fd = cast(redir_loc.Fd, UP_loc).fd
|
| 373 |
|
| 374 | else:
|
| 375 | raise AssertionError()
|
| 376 |
|
| 377 | self._PushSave(fd)
|
| 378 |
|
| 379 | return True
|
| 380 |
|
| 381 | def _PushClose(self, fd):
|
| 382 | # type: (int) -> None
|
| 383 | self.cur_frame.saved.append(_RedirFrame(NO_FD, fd, False))
|
| 384 |
|
| 385 | def _PushWait(self, proc):
|
| 386 | # type: (Process) -> None
|
| 387 | self.cur_frame.need_wait.append(proc)
|
| 388 |
|
| 389 | def _ApplyRedirect(self, r, err_out):
|
| 390 | # type: (RedirValue, List[int]) -> None
|
| 391 | arg = r.arg
|
| 392 | UP_arg = arg
|
| 393 | with tagswitch(arg) as case:
|
| 394 |
|
| 395 | if case(redirect_arg_e.Path):
|
| 396 | arg = cast(redirect_arg.Path, UP_arg)
|
| 397 |
|
| 398 | if r.op_id in (Id.Redir_Great, Id.Redir_AndGreat): # > &>
|
| 399 | mode = O_CREAT | O_WRONLY | O_TRUNC
|
| 400 | elif r.op_id == Id.Redir_Clobber: # >|
|
| 401 | mode = O_CREAT | O_WRONLY | O_TRUNC
|
| 402 | elif r.op_id in (Id.Redir_DGreat,
|
| 403 | Id.Redir_AndDGreat): # >> &>>
|
| 404 | mode = O_CREAT | O_WRONLY | O_APPEND
|
| 405 | elif r.op_id == Id.Redir_Less: # <
|
| 406 | mode = O_RDONLY
|
| 407 | elif r.op_id == Id.Redir_LessGreat: # <>
|
| 408 | mode = O_CREAT | O_RDWR
|
| 409 | else:
|
| 410 | raise NotImplementedError(r.op_id)
|
| 411 |
|
| 412 | # noclobber: don't overwrite existing files (except for special
|
| 413 | # files like /dev/null)
|
| 414 | noclobber = self.exec_opts.noclobber()
|
| 415 |
|
| 416 | # Only > and &> actually follow noclobber. See
|
| 417 | # spec/redirect.test.sh
|
| 418 | op_respects_noclobber = r.op_id in (Id.Redir_Great, Id.Redir_AndGreat)
|
| 419 |
|
| 420 | if noclobber and op_respects_noclobber:
|
| 421 | stat = mylib.stat(arg.filename)
|
| 422 | if not stat:
|
| 423 | # File doesn't currently exist, open with O_EXCL (open
|
| 424 | # will fail is EEXIST if arg.filename exists when we
|
| 425 | # call open(2)). This guards against a race where the
|
| 426 | # file may be created *after* we check it with stat.
|
| 427 | mode |= O_EXCL
|
| 428 |
|
| 429 | elif stat.isreg():
|
| 430 | # This is a regular file, opening it would clobber,
|
| 431 | # so raise an error.
|
| 432 | err_out.append(EEXIST)
|
| 433 | return
|
| 434 |
|
| 435 | # Otherwise, the file exists and is a special file like
|
| 436 | # /dev/null, we can open(2) it without O_EXCL. (Note,
|
| 437 | # there is a race here. See demo/noclobber-race.sh)
|
| 438 |
|
| 439 | # NOTE: 0666 is affected by umask, all shells use it.
|
| 440 | try:
|
| 441 | open_fd = posix.open(arg.filename, mode, 0o666)
|
| 442 | except (IOError, OSError) as e:
|
| 443 | if e.errno == EEXIST and noclobber:
|
| 444 | extra = ' (noclobber)'
|
| 445 | else:
|
| 446 | extra = ''
|
| 447 | self.errfmt.Print_(
|
| 448 | "Can't open %r: %s%s" %
|
| 449 | (arg.filename, pyutil.strerror(e), extra),
|
| 450 | blame_loc=r.op_loc)
|
| 451 | raise
|
| 452 |
|
| 453 | new_fd = self._PushDup(open_fd, r.loc)
|
| 454 | if new_fd != NO_FD:
|
| 455 | posix.close(open_fd)
|
| 456 |
|
| 457 | # Now handle &> and &>> and their variants. These pairs are the same:
|
| 458 | #
|
| 459 | # stdout_stderr.py &> out-err.txt
|
| 460 | # stdout_stderr.py > out-err.txt 2>&1
|
| 461 | #
|
| 462 | # stdout_stderr.py 3&> out-err.txt
|
| 463 | # stdout_stderr.py 3> out-err.txt 2>&3
|
| 464 | #
|
| 465 | # Ditto for {fd}> and {fd}&>
|
| 466 |
|
| 467 | if r.op_id in (Id.Redir_AndGreat, Id.Redir_AndDGreat):
|
| 468 | self._PushDup(new_fd, redir_loc.Fd(2))
|
| 469 |
|
| 470 | elif case(redirect_arg_e.CopyFd): # e.g. echo hi 1>&2
|
| 471 | arg = cast(redirect_arg.CopyFd, UP_arg)
|
| 472 |
|
| 473 | if r.op_id == Id.Redir_GreatAnd: # 1>&2
|
| 474 | self._PushDup(arg.target_fd, r.loc)
|
| 475 |
|
| 476 | elif r.op_id == Id.Redir_LessAnd: # 0<&5
|
| 477 | # The only difference between >& and <& is the default file
|
| 478 | # descriptor argument.
|
| 479 | self._PushDup(arg.target_fd, r.loc)
|
| 480 |
|
| 481 | else:
|
| 482 | raise NotImplementedError()
|
| 483 |
|
| 484 | elif case(redirect_arg_e.MoveFd): # e.g. echo hi 5>&6-
|
| 485 | arg = cast(redirect_arg.MoveFd, UP_arg)
|
| 486 | new_fd = self._PushDup(arg.target_fd, r.loc)
|
| 487 | if new_fd != NO_FD:
|
| 488 | posix.close(arg.target_fd)
|
| 489 |
|
| 490 | UP_loc = r.loc
|
| 491 | if r.loc.tag() == redir_loc_e.Fd:
|
| 492 | fd = cast(redir_loc.Fd, UP_loc).fd
|
| 493 | else:
|
| 494 | fd = NO_FD
|
| 495 |
|
| 496 | self.cur_frame.saved.append(_RedirFrame(new_fd, fd, False))
|
| 497 |
|
| 498 | elif case(redirect_arg_e.CloseFd): # e.g. echo hi 5>&-
|
| 499 | self._PushCloseFd(r.loc)
|
| 500 |
|
| 501 | elif case(redirect_arg_e.HereDoc):
|
| 502 | arg = cast(redirect_arg.HereDoc, UP_arg)
|
| 503 |
|
| 504 | # NOTE: Do these descriptors have to be moved out of the range 0-9?
|
| 505 | read_fd, write_fd = posix.pipe()
|
| 506 |
|
| 507 | self._PushDup(read_fd, r.loc) # stdin is now the pipe
|
| 508 |
|
| 509 | # We can't close like we do in the filename case above? The writer can
|
| 510 | # get a "broken pipe".
|
| 511 | self._PushClose(read_fd)
|
| 512 |
|
| 513 | thunk = _HereDocWriterThunk(write_fd, arg.body)
|
| 514 |
|
| 515 | # Use PIPE_SIZE to save a process in the case of small here
|
| 516 | # docs, which are the common case. (dash does this.)
|
| 517 |
|
| 518 | # Note: could instrument this to see how often it happens.
|
| 519 | # Though strace -ff can also work.
|
| 520 | start_process = len(arg.body) > 4096
|
| 521 | #start_process = True
|
| 522 |
|
| 523 | if start_process:
|
| 524 | here_proc = Process(thunk, self.job_control, self.job_list,
|
| 525 | self.tracer)
|
| 526 |
|
| 527 | # NOTE: we could close the read pipe here, but it doesn't really
|
| 528 | # matter because we control the code.
|
| 529 | here_proc.StartProcess(trace.HereDoc)
|
| 530 | #log('Started %s as %d', here_proc, pid)
|
| 531 | self._PushWait(here_proc)
|
| 532 |
|
| 533 | # Now that we've started the child, close it in the parent.
|
| 534 | posix.close(write_fd)
|
| 535 |
|
| 536 | else:
|
| 537 | posix.write(write_fd, arg.body)
|
| 538 | posix.close(write_fd)
|
| 539 |
|
| 540 | def Push(self, redirects, err_out):
|
| 541 | # type: (List[RedirValue], List[int]) -> None
|
| 542 | """Apply a group of redirects and remember to undo them."""
|
| 543 |
|
| 544 | #log('> fd_state.Push %s', redirects)
|
| 545 | new_frame = _FdFrame()
|
| 546 | self.stack.append(new_frame)
|
| 547 | self.cur_frame = new_frame
|
| 548 |
|
| 549 | for r in redirects:
|
| 550 | #log('apply %s', r)
|
| 551 | with ui.ctx_Location(self.errfmt, r.op_loc):
|
| 552 | try:
|
| 553 | # _ApplyRedirect reports errors in 2 ways:
|
| 554 | # 1. Raising an IOError or OSError from posix.* calls
|
| 555 | # 2. Returning errors in err_out from checks like noclobber
|
| 556 | self._ApplyRedirect(r, err_out)
|
| 557 | except (IOError, OSError) as e:
|
| 558 | err_out.append(e.errno)
|
| 559 |
|
| 560 | if len(err_out):
|
| 561 | # This can fail too
|
| 562 | self.Pop(err_out)
|
| 563 | return # for bad descriptor, etc.
|
| 564 |
|
| 565 | def PushStdinFromPipe(self, r):
|
| 566 | # type: (int) -> bool
|
| 567 | """Save the current stdin and make it come from descriptor 'r'.
|
| 568 |
|
| 569 | 'r' is typically the read-end of a pipe. For 'lastpipe'/ZSH
|
| 570 | semantics of
|
| 571 |
|
| 572 | echo foo | read line; echo $line
|
| 573 | """
|
| 574 | new_frame = _FdFrame()
|
| 575 | self.stack.append(new_frame)
|
| 576 | self.cur_frame = new_frame
|
| 577 |
|
| 578 | self._PushDup(r, redir_loc.Fd(0))
|
| 579 | return True
|
| 580 |
|
| 581 | def Pop(self, err_out):
|
| 582 | # type: (List[int]) -> None
|
| 583 | frame = self.stack.pop()
|
| 584 | #log('< Pop %s', frame)
|
| 585 | for rf in reversed(frame.saved):
|
| 586 | if rf.saved_fd == NO_FD:
|
| 587 | #log('Close %d', orig)
|
| 588 | try:
|
| 589 | posix.close(rf.orig_fd)
|
| 590 | except (IOError, OSError) as e:
|
| 591 | err_out.append(e.errno)
|
| 592 | log('Error closing descriptor %d: %s', rf.orig_fd,
|
| 593 | pyutil.strerror(e))
|
| 594 | return
|
| 595 | else:
|
| 596 | try:
|
| 597 | posix.dup2(rf.saved_fd, rf.orig_fd)
|
| 598 | except (IOError, OSError) as e:
|
| 599 | err_out.append(e.errno)
|
| 600 | log('dup2(%d, %d) error: %s', rf.saved_fd, rf.orig_fd,
|
| 601 | pyutil.strerror(e))
|
| 602 | #log('fd state:')
|
| 603 | #posix.system('ls -l /proc/%s/fd' % posix.getpid())
|
| 604 | return
|
| 605 | posix.close(rf.saved_fd)
|
| 606 | #log('dup2 %s %s', saved, orig)
|
| 607 |
|
| 608 | # Wait for here doc processes to finish.
|
| 609 | for proc in frame.need_wait:
|
| 610 | unused_status = proc.Wait(self.waiter)
|
| 611 |
|
| 612 | def MakePermanent(self):
|
| 613 | # type: () -> None
|
| 614 | self.cur_frame.Forget()
|
| 615 |
|
| 616 |
|
| 617 | class ChildStateChange(object):
|
| 618 |
|
| 619 | def __init__(self):
|
| 620 | # type: () -> None
|
| 621 | """Empty constructor for mycpp."""
|
| 622 | pass
|
| 623 |
|
| 624 | def Apply(self):
|
| 625 | # type: () -> None
|
| 626 | raise NotImplementedError()
|
| 627 |
|
| 628 | def ApplyFromParent(self, proc):
|
| 629 | # type: (Process) -> None
|
| 630 | """Noop for all state changes other than SetPgid for mycpp."""
|
| 631 | pass
|
| 632 |
|
| 633 |
|
| 634 | class StdinFromPipe(ChildStateChange):
|
| 635 |
|
| 636 | def __init__(self, pipe_read_fd, w):
|
| 637 | # type: (int, int) -> None
|
| 638 | self.r = pipe_read_fd
|
| 639 | self.w = w
|
| 640 |
|
| 641 | def __repr__(self):
|
| 642 | # type: () -> str
|
| 643 | return '<StdinFromPipe %d %d>' % (self.r, self.w)
|
| 644 |
|
| 645 | def Apply(self):
|
| 646 | # type: () -> None
|
| 647 | posix.dup2(self.r, 0)
|
| 648 | posix.close(self.r) # close after dup
|
| 649 |
|
| 650 | posix.close(self.w) # we're reading from the pipe, not writing
|
| 651 | #log('child CLOSE w %d pid=%d', self.w, posix.getpid())
|
| 652 |
|
| 653 |
|
| 654 | class StdoutToPipe(ChildStateChange):
|
| 655 |
|
| 656 | def __init__(self, r, pipe_write_fd):
|
| 657 | # type: (int, int) -> None
|
| 658 | self.r = r
|
| 659 | self.w = pipe_write_fd
|
| 660 |
|
| 661 | def __repr__(self):
|
| 662 | # type: () -> str
|
| 663 | return '<StdoutToPipe %d %d>' % (self.r, self.w)
|
| 664 |
|
| 665 | def Apply(self):
|
| 666 | # type: () -> None
|
| 667 | posix.dup2(self.w, 1)
|
| 668 | posix.close(self.w) # close after dup
|
| 669 |
|
| 670 | posix.close(self.r) # we're writing to the pipe, not reading
|
| 671 | #log('child CLOSE r %d pid=%d', self.r, posix.getpid())
|
| 672 |
|
| 673 |
|
| 674 | class StderrToPipe(ChildStateChange):
|
| 675 |
|
| 676 | def __init__(self, r, pipe_write_fd):
|
| 677 | # type: (int, int) -> None
|
| 678 | self.r = r
|
| 679 | self.w = pipe_write_fd
|
| 680 |
|
| 681 | def __repr__(self):
|
| 682 | # type: () -> str
|
| 683 | return '<StderrToPipe %d %d>' % (self.r, self.w)
|
| 684 |
|
| 685 | def Apply(self):
|
| 686 | # type: () -> None
|
| 687 | posix.dup2(self.w, 2)
|
| 688 | posix.close(self.w) # close after dup
|
| 689 |
|
| 690 | posix.close(self.r) # we're writing to the pipe, not reading
|
| 691 | #log('child CLOSE r %d pid=%d', self.r, posix.getpid())
|
| 692 |
|
| 693 |
|
| 694 | INVALID_PGID = -1
|
| 695 | # argument to setpgid() that means the process is its own leader
|
| 696 | OWN_LEADER = 0
|
| 697 |
|
| 698 |
|
| 699 | class SetPgid(ChildStateChange):
|
| 700 |
|
| 701 | def __init__(self, pgid, tracer):
|
| 702 | # type: (int, dev.Tracer) -> None
|
| 703 | self.pgid = pgid
|
| 704 | self.tracer = tracer
|
| 705 |
|
| 706 | def Apply(self):
|
| 707 | # type: () -> None
|
| 708 | try:
|
| 709 | posix.setpgid(0, self.pgid)
|
| 710 | except (IOError, OSError) as e:
|
| 711 | self.tracer.OtherMessage(
|
| 712 | 'osh: child %d failed to set its process group to %d: %s' %
|
| 713 | (posix.getpid(), self.pgid, pyutil.strerror(e)))
|
| 714 |
|
| 715 | def ApplyFromParent(self, proc):
|
| 716 | # type: (Process) -> None
|
| 717 | try:
|
| 718 | posix.setpgid(proc.pid, self.pgid)
|
| 719 | except (IOError, OSError) as e:
|
| 720 | self.tracer.OtherMessage(
|
| 721 | 'osh: parent failed to set process group for PID %d to %d: %s'
|
| 722 | % (proc.pid, self.pgid, pyutil.strerror(e)))
|
| 723 |
|
| 724 |
|
| 725 | class ExternalProgram(object):
|
| 726 | """The capability to execute an external program like 'ls'."""
|
| 727 |
|
| 728 | def __init__(
|
| 729 | self,
|
| 730 | hijack_shebang, # type: str
|
| 731 | fd_state, # type: FdState
|
| 732 | errfmt, # type: ui.ErrorFormatter
|
| 733 | debug_f, # type: _DebugFile
|
| 734 | ):
|
| 735 | # type: (...) -> None
|
| 736 | """
|
| 737 | Args:
|
| 738 | hijack_shebang: The path of an interpreter to run instead of the one
|
| 739 | specified in the shebang line. May be empty.
|
| 740 | """
|
| 741 | self.hijack_shebang = hijack_shebang
|
| 742 | self.fd_state = fd_state
|
| 743 | self.errfmt = errfmt
|
| 744 | self.debug_f = debug_f
|
| 745 |
|
| 746 | def Exec(self, argv0_path, cmd_val, environ):
|
| 747 | # type: (str, cmd_value.Argv, Dict[str, str]) -> None
|
| 748 | """Execute a program and exit this process.
|
| 749 |
|
| 750 | Called by: ls / exec ls / ( ls / )
|
| 751 | """
|
| 752 | probe('process', 'ExternalProgram_Exec', argv0_path)
|
| 753 | self._Exec(argv0_path, cmd_val.argv, cmd_val.arg_locs[0], environ,
|
| 754 | True)
|
| 755 | assert False, "This line should never execute" # NO RETURN
|
| 756 |
|
| 757 | def _Exec(self, argv0_path, argv, argv0_loc, environ, should_retry):
|
| 758 | # type: (str, List[str], loc_t, Dict[str, str], bool) -> None
|
| 759 | if len(self.hijack_shebang):
|
| 760 | opened = True
|
| 761 | try:
|
| 762 | f = self.fd_state.Open(argv0_path)
|
| 763 | except (IOError, OSError) as e:
|
| 764 | opened = False
|
| 765 |
|
| 766 | if opened:
|
| 767 | with ctx_FileCloser(f):
|
| 768 | # Test if the shebang looks like a shell. TODO: The file might be
|
| 769 | # binary with no newlines, so read 80 bytes instead of readline().
|
| 770 |
|
| 771 | #line = f.read(80) # type: ignore # TODO: fix this
|
| 772 | line = f.readline()
|
| 773 |
|
| 774 | if match.ShouldHijack(line):
|
| 775 | h_argv = [self.hijack_shebang, argv0_path]
|
| 776 | h_argv.extend(argv[1:])
|
| 777 | argv = h_argv
|
| 778 | argv0_path = self.hijack_shebang
|
| 779 | self.debug_f.writeln('Hijacked: %s' % argv0_path)
|
| 780 | else:
|
| 781 | #self.debug_f.log('Not hijacking %s (%r)', argv, line)
|
| 782 | pass
|
| 783 |
|
| 784 | try:
|
| 785 | posix.execve(argv0_path, argv, environ)
|
| 786 | except (IOError, OSError) as e:
|
| 787 | # Run with /bin/sh when ENOEXEC error (no shebang). All shells do this.
|
| 788 | if e.errno == ENOEXEC and should_retry:
|
| 789 | new_argv = ['/bin/sh', argv0_path]
|
| 790 | new_argv.extend(argv[1:])
|
| 791 | self._Exec('/bin/sh', new_argv, argv0_loc, environ, False)
|
| 792 | # NO RETURN
|
| 793 |
|
| 794 | # Would be nice: when the path is relative and ENOENT: print PWD and do
|
| 795 | # spelling correction?
|
| 796 |
|
| 797 | self.errfmt.Print_(
|
| 798 | "Can't execute %r: %s" % (argv0_path, pyutil.strerror(e)),
|
| 799 | argv0_loc)
|
| 800 |
|
| 801 | # POSIX mentions 126 and 127 for two specific errors. The rest are
|
| 802 | # unspecified.
|
| 803 | #
|
| 804 | # http://pubs.opengroup.org/onlinepubs/9699919799.2016edition/utilities/V3_chap02.html#tag_18_08_02
|
| 805 | if e.errno == EACCES:
|
| 806 | status = 126
|
| 807 | elif e.errno == ENOENT:
|
| 808 | # TODO: most shells print 'command not found', rather than strerror()
|
| 809 | # == "No such file or directory". That's better because it's at the
|
| 810 | # end of the path search, and we're never searching for a directory.
|
| 811 | status = 127
|
| 812 | else:
|
| 813 | # dash uses 2, but we use that for parse errors. This seems to be
|
| 814 | # consistent with mksh and zsh.
|
| 815 | status = 127
|
| 816 |
|
| 817 | posix._exit(status)
|
| 818 | # NO RETURN
|
| 819 |
|
| 820 |
|
| 821 | class Thunk(object):
|
| 822 | """Abstract base class for things runnable in another process."""
|
| 823 |
|
| 824 | def __init__(self):
|
| 825 | # type: () -> None
|
| 826 | """Empty constructor for mycpp."""
|
| 827 | pass
|
| 828 |
|
| 829 | def Run(self):
|
| 830 | # type: () -> None
|
| 831 | """Returns a status code."""
|
| 832 | raise NotImplementedError()
|
| 833 |
|
| 834 | def UserString(self):
|
| 835 | # type: () -> str
|
| 836 | """Display for the 'jobs' list."""
|
| 837 | raise NotImplementedError()
|
| 838 |
|
| 839 | def __repr__(self):
|
| 840 | # type: () -> str
|
| 841 | return self.UserString()
|
| 842 |
|
| 843 |
|
| 844 | class ExternalThunk(Thunk):
|
| 845 | """An external executable."""
|
| 846 |
|
| 847 | def __init__(self, ext_prog, argv0_path, cmd_val, environ):
|
| 848 | # type: (ExternalProgram, str, cmd_value.Argv, Dict[str, str]) -> None
|
| 849 | self.ext_prog = ext_prog
|
| 850 | self.argv0_path = argv0_path
|
| 851 | self.cmd_val = cmd_val
|
| 852 | self.environ = environ
|
| 853 |
|
| 854 | def UserString(self):
|
| 855 | # type: () -> str
|
| 856 |
|
| 857 | # NOTE: This is the format the Tracer uses.
|
| 858 | # bash displays sleep $n & (code)
|
| 859 | # but OSH displays sleep 1 & (argv array)
|
| 860 | # We could switch the former but I'm not sure it's necessary.
|
| 861 | tmp = [j8_lite.MaybeShellEncode(a) for a in self.cmd_val.argv]
|
| 862 | return '[process] %s' % ' '.join(tmp)
|
| 863 |
|
| 864 | def Run(self):
|
| 865 | # type: () -> None
|
| 866 | """An ExternalThunk is run in parent for the exec builtin."""
|
| 867 | self.ext_prog.Exec(self.argv0_path, self.cmd_val, self.environ)
|
| 868 |
|
| 869 |
|
| 870 | class BuiltinThunk(Thunk):
|
| 871 | """Builtin thunk - for running builtins in a forked subprocess"""
|
| 872 |
|
| 873 | def __init__(self, shell_ex, builtin_id, cmd_val):
|
| 874 | # type: (vm._Executor, int, cmd_value.Argv) -> None
|
| 875 | self.shell_ex = shell_ex
|
| 876 | self.builtin_id = builtin_id
|
| 877 | self.cmd_val = cmd_val
|
| 878 |
|
| 879 | def UserString(self):
|
| 880 | # type: () -> str
|
| 881 | tmp = [j8_lite.MaybeShellEncode(a) for a in self.cmd_val.argv]
|
| 882 | return '[builtin] %s' % ' '.join(tmp)
|
| 883 |
|
| 884 | def Run(self):
|
| 885 | # type: () -> None
|
| 886 | """No exec - we need to exit ourselves"""
|
| 887 | status = self.shell_ex.RunBuiltin(self.builtin_id, self.cmd_val)
|
| 888 | posix._exit(status)
|
| 889 |
|
| 890 |
|
| 891 | class SubProgramThunk(Thunk):
|
| 892 | """A subprogram that can be executed in another process."""
|
| 893 |
|
| 894 | def __init__(
|
| 895 | self,
|
| 896 | cmd_ev, # type: CommandEvaluator
|
| 897 | node, # type: command_t
|
| 898 | trap_state, # type: trap_osh.TrapState
|
| 899 | multi_trace, # type: dev.MultiTracer
|
| 900 | inherit_errexit, # type: bool
|
| 901 | inherit_errtrace, # type: bool
|
| 902 | ):
|
| 903 | # type: (...) -> None
|
| 904 | self.cmd_ev = cmd_ev
|
| 905 | self.node = node
|
| 906 | self.trap_state = trap_state
|
| 907 | self.multi_trace = multi_trace
|
| 908 | self.inherit_errexit = inherit_errexit # for bash errexit compatibility
|
| 909 | self.inherit_errtrace = inherit_errtrace # for bash errtrace compatibility
|
| 910 |
|
| 911 | def UserString(self):
|
| 912 | # type: () -> str
|
| 913 |
|
| 914 | # NOTE: These can be pieces of a pipeline, so they're arbitrary nodes.
|
| 915 | # TODO: Extract SPIDS from node to display source? Note that
|
| 916 | # CompoundStatus also has locations of each pipeline component; see
|
| 917 | # Executor.RunPipeline()
|
| 918 | thunk_str = ui.CommandType(self.node)
|
| 919 | return '[subprog] %s' % thunk_str
|
| 920 |
|
| 921 | def Run(self):
|
| 922 | # type: () -> None
|
| 923 | #self.errfmt.OneLineErrExit() # don't quote code in child processes
|
| 924 | probe('process', 'SubProgramThunk_Run')
|
| 925 |
|
| 926 | # TODO: break circular dep. Bit flags could go in ASDL or headers.
|
| 927 | from osh import cmd_eval
|
| 928 |
|
| 929 | # signal handlers aren't inherited
|
| 930 | self.trap_state.ClearForSubProgram(self.inherit_errtrace)
|
| 931 |
|
| 932 | # NOTE: may NOT return due to exec().
|
| 933 | if not self.inherit_errexit:
|
| 934 | self.cmd_ev.mutable_opts.DisableErrExit()
|
| 935 | try:
|
| 936 | # optimize to eliminate redundant subshells like ( echo hi ) | wc -l etc.
|
| 937 | self.cmd_ev.ExecuteAndCatch(
|
| 938 | self.node,
|
| 939 | cmd_eval.OptimizeSubshells | cmd_eval.MarkLastCommands)
|
| 940 | status = self.cmd_ev.LastStatus()
|
| 941 | # NOTE: We ignore the is_fatal return value. The user should set -o
|
| 942 | # errexit so failures in subprocesses cause failures in the parent.
|
| 943 | except util.HardExit as e:
|
| 944 | status = e.status
|
| 945 |
|
| 946 | # Handle errors in a subshell. These two cases are repeated from main()
|
| 947 | # and the core/completion.py hook.
|
| 948 | except KeyboardInterrupt:
|
| 949 | print('')
|
| 950 | status = 130 # 128 + 2
|
| 951 | except (IOError, OSError) as e:
|
| 952 | print_stderr('oils I/O error (subprogram): %s' %
|
| 953 | pyutil.strerror(e))
|
| 954 | status = 2
|
| 955 |
|
| 956 | # If ProcessInit() doesn't turn off buffering, this is needed before
|
| 957 | # _exit()
|
| 958 | pyos.FlushStdout()
|
| 959 |
|
| 960 | self.multi_trace.WriteDumps()
|
| 961 |
|
| 962 | # We do NOT want to raise SystemExit here. Otherwise dev.Tracer::Pop()
|
| 963 | # gets called in BOTH processes.
|
| 964 | # The crash dump seems to be unaffected.
|
| 965 | posix._exit(status)
|
| 966 |
|
| 967 |
|
| 968 | class _HereDocWriterThunk(Thunk):
|
| 969 | """Write a here doc to one end of a pipe.
|
| 970 |
|
| 971 | May be be executed in either a child process or the main shell
|
| 972 | process.
|
| 973 | """
|
| 974 |
|
| 975 | def __init__(self, w, body_str):
|
| 976 | # type: (int, str) -> None
|
| 977 | self.w = w
|
| 978 | self.body_str = body_str
|
| 979 |
|
| 980 | def UserString(self):
|
| 981 | # type: () -> str
|
| 982 |
|
| 983 | # You can hit Ctrl-Z and the here doc writer will be suspended! Other
|
| 984 | # shells don't have this problem because they use temp files! That's a bit
|
| 985 | # unfortunate.
|
| 986 | return '[here doc writer]'
|
| 987 |
|
| 988 | def Run(self):
|
| 989 | # type: () -> None
|
| 990 | """do_exit: For small pipelines."""
|
| 991 | probe('process', 'HereDocWriterThunk_Run')
|
| 992 | #log('Writing %r', self.body_str)
|
| 993 | posix.write(self.w, self.body_str)
|
| 994 | #log('Wrote %r', self.body_str)
|
| 995 | posix.close(self.w)
|
| 996 | #log('Closed %d', self.w)
|
| 997 |
|
| 998 | posix._exit(0)
|
| 999 |
|
| 1000 |
|
| 1001 | class Job(object):
|
| 1002 | """Interface for both Process and Pipeline.
|
| 1003 |
|
| 1004 | They both can be put in the background and waited on.
|
| 1005 |
|
| 1006 | Confusing thing about pipelines in the background: They have TOO MANY NAMES.
|
| 1007 |
|
| 1008 | sleep 1 | sleep 2 &
|
| 1009 |
|
| 1010 | - The LAST PID is what's printed at the prompt. This is $!, a PROCESS ID and
|
| 1011 | not a JOB ID.
|
| 1012 | # https://www.gnu.org/software/bash/manual/html_node/Special-Parameters.html#Special-Parameters
|
| 1013 | - The process group leader (setpgid) is the FIRST PID.
|
| 1014 | - It's also %1 or %+. The last job started.
|
| 1015 | """
|
| 1016 |
|
| 1017 | def __init__(self):
|
| 1018 | # type: () -> None
|
| 1019 | # Initial state with & or Ctrl-Z is Running.
|
| 1020 | self.state = job_state_e.Running
|
| 1021 | self.job_id = -1
|
| 1022 | self.in_background = False
|
| 1023 |
|
| 1024 | def DisplayJob(self, job_id, f, style):
|
| 1025 | # type: (int, mylib.Writer, int) -> None
|
| 1026 | raise NotImplementedError()
|
| 1027 |
|
| 1028 | def State(self):
|
| 1029 | # type: () -> job_state_t
|
| 1030 | return self.state
|
| 1031 |
|
| 1032 | def ProcessGroupId(self):
|
| 1033 | # type: () -> int
|
| 1034 | """Return the process group ID associated with this job."""
|
| 1035 | raise NotImplementedError()
|
| 1036 |
|
| 1037 | def PidForWait(self):
|
| 1038 | # type: () -> int
|
| 1039 | """Return the pid we can wait on."""
|
| 1040 | raise NotImplementedError()
|
| 1041 |
|
| 1042 | def JobWait(self, waiter):
|
| 1043 | # type: (Waiter) -> wait_status_t
|
| 1044 | """Wait for this process/pipeline to be stopped or finished."""
|
| 1045 | raise NotImplementedError()
|
| 1046 |
|
| 1047 | def SetBackground(self):
|
| 1048 | # type: () -> None
|
| 1049 | """Record that this job is running in the background."""
|
| 1050 | self.in_background = True
|
| 1051 |
|
| 1052 | def SetForeground(self):
|
| 1053 | # type: () -> None
|
| 1054 | """Record that this job is running in the foreground."""
|
| 1055 | self.in_background = False
|
| 1056 |
|
| 1057 |
|
| 1058 | class Process(Job):
|
| 1059 | """A process to run.
|
| 1060 |
|
| 1061 | TODO: Should we make it clear that this is a FOREGROUND process? A
|
| 1062 | background process is wrapped in a "job". It is unevaluated.
|
| 1063 |
|
| 1064 | It provides an API to manipulate file descriptor state in parent and child.
|
| 1065 | """
|
| 1066 |
|
| 1067 | def __init__(self, thunk, job_control, job_list, tracer):
|
| 1068 | # type: (Thunk, JobControl, JobList, dev.Tracer) -> None
|
| 1069 | """
|
| 1070 | Args:
|
| 1071 | thunk: Thunk instance
|
| 1072 | job_list: for process bookkeeping
|
| 1073 | """
|
| 1074 | Job.__init__(self)
|
| 1075 | assert isinstance(thunk, Thunk), thunk
|
| 1076 | self.thunk = thunk
|
| 1077 | self.job_control = job_control
|
| 1078 | self.job_list = job_list
|
| 1079 | self.tracer = tracer
|
| 1080 | self.exec_opts = tracer.exec_opts
|
| 1081 |
|
| 1082 | # For pipelines
|
| 1083 | self.parent_pipeline = None # type: Pipeline
|
| 1084 | self.state_changes = [] # type: List[ChildStateChange]
|
| 1085 | self.close_r = -1
|
| 1086 | self.close_w = -1
|
| 1087 |
|
| 1088 | self.pid = -1
|
| 1089 | self.status = -1
|
| 1090 |
|
| 1091 | def Init_ParentPipeline(self, pi):
|
| 1092 | # type: (Pipeline) -> None
|
| 1093 | """For updating PIPESTATUS."""
|
| 1094 | self.parent_pipeline = pi
|
| 1095 |
|
| 1096 | def __repr__(self):
|
| 1097 | # type: () -> str
|
| 1098 |
|
| 1099 | # note: be wary of infinite mutual recursion
|
| 1100 | #s = ' %s' % self.parent_pipeline if self.parent_pipeline else ''
|
| 1101 | #return '<Process %s%s>' % (self.thunk, s)
|
| 1102 | return '<Process pid=%d state=%s %s>' % (
|
| 1103 | self.pid, _JobStateStr(self.state), self.thunk)
|
| 1104 |
|
| 1105 | def ProcessGroupId(self):
|
| 1106 | # type: () -> int
|
| 1107 | """Returns the group ID of this process."""
|
| 1108 | # This should only ever be called AFTER the process has started
|
| 1109 | assert self.pid != -1
|
| 1110 | if self.parent_pipeline:
|
| 1111 | # XXX: Maybe we should die here instead? Unclear if this branch
|
| 1112 | # should even be reachable with the current builtins.
|
| 1113 | return self.parent_pipeline.ProcessGroupId()
|
| 1114 |
|
| 1115 | return self.pid
|
| 1116 |
|
| 1117 | def PidForWait(self):
|
| 1118 | # type: () -> int
|
| 1119 | """Return the pid we can wait on."""
|
| 1120 | assert self.pid != -1
|
| 1121 | return self.pid
|
| 1122 |
|
| 1123 | def DisplayJob(self, job_id, f, style):
|
| 1124 | # type: (int, mylib.Writer, int) -> None
|
| 1125 | if job_id == -1:
|
| 1126 | job_id_str = ' '
|
| 1127 | else:
|
| 1128 | job_id_str = '%%%d' % job_id
|
| 1129 | if style == STYLE_PID_ONLY:
|
| 1130 | f.write('%d\n' % self.pid)
|
| 1131 | else:
|
| 1132 | f.write('%s %d %7s ' %
|
| 1133 | (job_id_str, self.pid, _JobStateStr(self.state)))
|
| 1134 | f.write(self.thunk.UserString())
|
| 1135 | f.write('\n')
|
| 1136 |
|
| 1137 | def AddStateChange(self, s):
|
| 1138 | # type: (ChildStateChange) -> None
|
| 1139 | self.state_changes.append(s)
|
| 1140 |
|
| 1141 | def AddPipeToClose(self, r, w):
|
| 1142 | # type: (int, int) -> None
|
| 1143 | self.close_r = r
|
| 1144 | self.close_w = w
|
| 1145 |
|
| 1146 | def MaybeClosePipe(self):
|
| 1147 | # type: () -> None
|
| 1148 | if self.close_r != -1:
|
| 1149 | posix.close(self.close_r)
|
| 1150 | posix.close(self.close_w)
|
| 1151 |
|
| 1152 | def StartProcess(self, why):
|
| 1153 | # type: (trace_t) -> int
|
| 1154 | """Start this process with fork(), handling redirects."""
|
| 1155 | pid = posix.fork()
|
| 1156 | if pid < 0:
|
| 1157 | # When does this happen?
|
| 1158 | e_die('Fatal error in posix.fork()')
|
| 1159 |
|
| 1160 | elif pid == 0: # child
|
| 1161 | # Note: this happens in BOTH interactive and non-interactive shells.
|
| 1162 | # We technically don't need to do most of it in non-interactive, since we
|
| 1163 | # did not change state in InitInteractiveShell().
|
| 1164 |
|
| 1165 | for st in self.state_changes:
|
| 1166 | st.Apply()
|
| 1167 |
|
| 1168 | # Python sets SIGPIPE handler to SIG_IGN by default. Child processes
|
| 1169 | # shouldn't have this.
|
| 1170 | # https://docs.python.org/2/library/signal.html
|
| 1171 | # See Python/pythonrun.c.
|
| 1172 | iolib.sigaction(SIGPIPE, SIG_DFL)
|
| 1173 |
|
| 1174 | # Respond to Ctrl-\ (core dump)
|
| 1175 | iolib.sigaction(SIGQUIT, SIG_DFL)
|
| 1176 |
|
| 1177 | # Only standalone children should get Ctrl-Z. Pipelines remain in the
|
| 1178 | # foreground because suspending them is difficult with our 'lastpipe'
|
| 1179 | # semantics.
|
| 1180 | pid = posix.getpid()
|
| 1181 | if posix.getpgid(0) == pid and self.parent_pipeline is None:
|
| 1182 | iolib.sigaction(SIGTSTP, SIG_DFL)
|
| 1183 |
|
| 1184 | # More signals from
|
| 1185 | # https://www.gnu.org/software/libc/manual/html_node/Launching-Jobs.html
|
| 1186 | # (but not SIGCHLD)
|
| 1187 | iolib.sigaction(SIGTTOU, SIG_DFL)
|
| 1188 | iolib.sigaction(SIGTTIN, SIG_DFL)
|
| 1189 |
|
| 1190 | self.tracer.OnNewProcess(pid)
|
| 1191 | # clear foreground pipeline for subshells
|
| 1192 | self.thunk.Run()
|
| 1193 | # Never returns
|
| 1194 |
|
| 1195 | #log('STARTED process %s, pid = %d', self, pid)
|
| 1196 | self.tracer.OnProcessStart(pid, why)
|
| 1197 |
|
| 1198 | # Class invariant: after the process is started, it stores its PID.
|
| 1199 | self.pid = pid
|
| 1200 |
|
| 1201 | # SetPgid needs to be applied from the child and the parent to avoid
|
| 1202 | # racing in calls to tcsetpgrp() in the parent. See APUE sec. 9.2.
|
| 1203 | for st in self.state_changes:
|
| 1204 | st.ApplyFromParent(self)
|
| 1205 |
|
| 1206 | # Program invariant: We keep track of every child process!
|
| 1207 | # Waiter::WaitForOne() needs it to update state
|
| 1208 | self.job_list.AddChildProcess(pid, self)
|
| 1209 |
|
| 1210 | return pid
|
| 1211 |
|
| 1212 | def Wait(self, waiter):
|
| 1213 | # type: (Waiter) -> int
|
| 1214 | """Wait for this Process to finish."""
|
| 1215 | # Keep waiting if waitpid() was interrupted with a signal (unlike the
|
| 1216 | # 'wait' builtin)
|
| 1217 | while self.state == job_state_e.Running:
|
| 1218 | result, _ = waiter.WaitForOne()
|
| 1219 | if result == W1_NO_CHILDREN:
|
| 1220 | break
|
| 1221 |
|
| 1222 | # Linear search
|
| 1223 | # if we get a W1_EXITED event, and the pid is OUR PID, then we can
|
| 1224 | # return?
|
| 1225 | # well we need the status too
|
| 1226 |
|
| 1227 | # Cleanup - for background jobs this happens in the 'wait' builtin,
|
| 1228 | # e.g. after JobWait()
|
| 1229 | if self.state == job_state_e.Exited:
|
| 1230 | self.job_list.PopChildProcess(self.pid)
|
| 1231 |
|
| 1232 | assert self.status >= 0, self.status
|
| 1233 | return self.status
|
| 1234 |
|
| 1235 | def JobWait(self, waiter):
|
| 1236 | # type: (Waiter) -> wait_status_t
|
| 1237 | """Process::JobWait, called by wait builtin"""
|
| 1238 | # wait builtin can be interrupted
|
| 1239 | while self.state == job_state_e.Running:
|
| 1240 | result, w1_arg = waiter.WaitForOne() # mutates self.state
|
| 1241 |
|
| 1242 | if result == W1_CALL_INTR:
|
| 1243 | return wait_status.Cancelled(w1_arg)
|
| 1244 |
|
| 1245 | if result == W1_NO_CHILDREN:
|
| 1246 | break
|
| 1247 |
|
| 1248 | # Ignore W1_EXITED, W1_STOPPED - these are OTHER processes
|
| 1249 |
|
| 1250 | assert self.status >= 0, self.status
|
| 1251 | return wait_status.Proc(self.state, self.status)
|
| 1252 |
|
| 1253 | def WhenContinued(self):
|
| 1254 | # type: () -> None
|
| 1255 | self.state = job_state_e.Running
|
| 1256 |
|
| 1257 | if self.parent_pipeline:
|
| 1258 | # TODO: do we need anything here?
|
| 1259 | pass
|
| 1260 |
|
| 1261 | # TODO: Should we remove it as a job?
|
| 1262 |
|
| 1263 | # Now job_id is set
|
| 1264 | if self.exec_opts.interactive():
|
| 1265 | #if 0:
|
| 1266 | print_stderr('[%%%d] PID %d Continued' % (self.job_id, self.pid))
|
| 1267 |
|
| 1268 | #if self.in_background:
|
| 1269 | if 1:
|
| 1270 | self.job_control.MaybeTakeTerminal()
|
| 1271 | self.SetForeground()
|
| 1272 |
|
| 1273 | def WhenStopped(self, stop_sig):
|
| 1274 | # type: (int) -> None
|
| 1275 | """Called by the Waiter when this Process is stopped."""
|
| 1276 | # 128 is a shell thing
|
| 1277 | # https://www.gnu.org/software/bash/manual/html_node/Exit-Status.html
|
| 1278 | self.status = 128 + stop_sig
|
| 1279 | self.state = job_state_e.Stopped
|
| 1280 |
|
| 1281 | if self.parent_pipeline:
|
| 1282 | # TODO: do we need anything here?
|
| 1283 | # We need AllStopped() just like AllExited()?
|
| 1284 |
|
| 1285 | #self.parent_pipeline.WhenPartIsStopped(pid, status)
|
| 1286 | #return
|
| 1287 | pass
|
| 1288 |
|
| 1289 | if self.job_id == -1:
|
| 1290 | # This process was started in the foreground, not with &. So it
|
| 1291 | # was NOT a job, but after Ctrl-Z, it's a job.
|
| 1292 | self.job_list.RegisterJob(self)
|
| 1293 |
|
| 1294 | # Now self.job_id is set
|
| 1295 | if self.exec_opts.interactive():
|
| 1296 | print_stderr('') # newline after ^Z (TODO: consolidate with ^C)
|
| 1297 | print_stderr('[%%%d] PID %d Stopped with signal %d' %
|
| 1298 | (self.job_id, self.pid, stop_sig))
|
| 1299 |
|
| 1300 | if not self.in_background:
|
| 1301 | # e.g. sleep 5; then Ctrl-Z
|
| 1302 | self.job_control.MaybeTakeTerminal()
|
| 1303 | self.SetBackground()
|
| 1304 |
|
| 1305 | def WhenExited(self, pid, status):
|
| 1306 | # type: (int, int) -> None
|
| 1307 | """Called by the Waiter when this Process exits."""
|
| 1308 |
|
| 1309 | #log('Process WhenExited %d %d', pid, status)
|
| 1310 | assert pid == self.pid, 'Expected %d, got %d' % (self.pid, pid)
|
| 1311 | self.status = status
|
| 1312 | self.state = job_state_e.Exited
|
| 1313 |
|
| 1314 | if self.parent_pipeline:
|
| 1315 | # populate pipeline status array; update Pipeline state, etc.
|
| 1316 | self.parent_pipeline.WhenPartExited(pid, status)
|
| 1317 | return
|
| 1318 |
|
| 1319 | if self.job_id != -1 and self.in_background:
|
| 1320 | # TODO: ONE condition should determine if this was a background
|
| 1321 | # job, rather than a foreground process
|
| 1322 | # "Job might have been brought to the foreground after being
|
| 1323 | # assigned a job ID"
|
| 1324 | if self.exec_opts.interactive():
|
| 1325 | print_stderr('[%%%d] PID %d Done' % (self.job_id, self.pid))
|
| 1326 |
|
| 1327 | if not self.in_background:
|
| 1328 | self.job_control.MaybeTakeTerminal()
|
| 1329 |
|
| 1330 | def RunProcess(self, waiter, why):
|
| 1331 | # type: (Waiter, trace_t) -> int
|
| 1332 | """Run this process synchronously."""
|
| 1333 | self.StartProcess(why)
|
| 1334 | # ShellExecutor might be calling this for the last part of a pipeline.
|
| 1335 | if self.parent_pipeline is None:
|
| 1336 | # QUESTION: Can the PGID of a single process just be the PID? i.e. avoid
|
| 1337 | # calling getpgid()?
|
| 1338 | self.job_control.MaybeGiveTerminal(posix.getpgid(self.pid))
|
| 1339 | return self.Wait(waiter)
|
| 1340 |
|
| 1341 |
|
| 1342 | class ctx_Pipe(object):
|
| 1343 |
|
| 1344 | def __init__(self, fd_state, fd, err_out):
|
| 1345 | # type: (FdState, int, List[int]) -> None
|
| 1346 | fd_state.PushStdinFromPipe(fd)
|
| 1347 | self.fd_state = fd_state
|
| 1348 | self.err_out = err_out
|
| 1349 |
|
| 1350 | def __enter__(self):
|
| 1351 | # type: () -> None
|
| 1352 | pass
|
| 1353 |
|
| 1354 | def __exit__(self, type, value, traceback):
|
| 1355 | # type: (Any, Any, Any) -> None
|
| 1356 | self.fd_state.Pop(self.err_out)
|
| 1357 |
|
| 1358 |
|
| 1359 | class Pipeline(Job):
|
| 1360 | """A pipeline of processes to run.
|
| 1361 |
|
| 1362 | Cases we handle:
|
| 1363 |
|
| 1364 | foo | bar
|
| 1365 | $(foo | bar)
|
| 1366 | foo | bar | read v
|
| 1367 | """
|
| 1368 |
|
| 1369 | def __init__(self, sigpipe_status_ok, job_control, job_list, tracer):
|
| 1370 | # type: (bool, JobControl, JobList, dev.Tracer) -> None
|
| 1371 | Job.__init__(self)
|
| 1372 | self.job_control = job_control
|
| 1373 | self.job_list = job_list
|
| 1374 | self.tracer = tracer
|
| 1375 | self.exec_opts = tracer.exec_opts
|
| 1376 |
|
| 1377 | self.procs = [] # type: List[Process]
|
| 1378 | self.pids = [] # type: List[int] # pids in order
|
| 1379 | self.pipe_status = [] # type: List[int] # status in order
|
| 1380 | self.status = -1 # for 'wait' jobs
|
| 1381 |
|
| 1382 | self.pgid = INVALID_PGID
|
| 1383 |
|
| 1384 | # Optional for foreground
|
| 1385 | self.last_thunk = None # type: Tuple[CommandEvaluator, command_t]
|
| 1386 | self.last_pipe = None # type: Tuple[int, int]
|
| 1387 |
|
| 1388 | self.sigpipe_status_ok = sigpipe_status_ok
|
| 1389 |
|
| 1390 | def __repr__(self):
|
| 1391 | # type: () -> str
|
| 1392 | return '<Pipeline pgid=%d pids=%s state=%s procs=%s>' % (
|
| 1393 | self.pgid, self.pids, _JobStateStr(self.state), self.procs)
|
| 1394 |
|
| 1395 | def ProcessGroupId(self):
|
| 1396 | # type: () -> int
|
| 1397 | """Returns the group ID of this pipeline.
|
| 1398 |
|
| 1399 | In an interactive shell, it's often the FIRST.
|
| 1400 | """
|
| 1401 | return self.pgid
|
| 1402 |
|
| 1403 | def PidForWait(self):
|
| 1404 | # type: () -> int
|
| 1405 | """Return the PID we can wait on.
|
| 1406 |
|
| 1407 | This is the same as the PID for $!
|
| 1408 |
|
| 1409 | Shell WART:
|
| 1410 | The $! variable is the PID of the LAST pipeline part.
|
| 1411 | But in an interactive shell, the PGID is the PID of the FIRST pipeline part.
|
| 1412 | It would be nicer if these were consistent!
|
| 1413 | """
|
| 1414 | return self.pids[-1]
|
| 1415 |
|
| 1416 | def DisplayJob(self, job_id, f, style):
|
| 1417 | # type: (int, mylib.Writer, int) -> None
|
| 1418 | if style == STYLE_PID_ONLY:
|
| 1419 | f.write('%d\n' % self.procs[0].pid)
|
| 1420 | else:
|
| 1421 | # Note: this is STYLE_LONG.
|
| 1422 | for i, proc in enumerate(self.procs):
|
| 1423 | if i == 0: # show job ID for first element in pipeline
|
| 1424 | job_id_str = '%%%d' % job_id
|
| 1425 | else:
|
| 1426 | job_id_str = ' ' # 2 spaces
|
| 1427 |
|
| 1428 | f.write('%s %d %7s ' %
|
| 1429 | (job_id_str, proc.pid, _JobStateStr(proc.state)))
|
| 1430 | f.write(proc.thunk.UserString())
|
| 1431 | f.write('\n')
|
| 1432 |
|
| 1433 | def DebugPrint(self):
|
| 1434 | # type: () -> None
|
| 1435 | print('Pipeline in state %s' % _JobStateStr(self.state))
|
| 1436 | if mylib.PYTHON: # %s for Process not allowed in C++
|
| 1437 | for proc in self.procs:
|
| 1438 | print(' proc %s' % proc)
|
| 1439 | _, last_node = self.last_thunk
|
| 1440 | print(' last %s' % last_node)
|
| 1441 | print(' pipe_status %s' % self.pipe_status)
|
| 1442 |
|
| 1443 | def Add(self, p):
|
| 1444 | # type: (Process) -> None
|
| 1445 | """Append a process to the pipeline."""
|
| 1446 | if len(self.procs) == 0:
|
| 1447 | self.procs.append(p)
|
| 1448 | return
|
| 1449 |
|
| 1450 | r, w = posix.pipe()
|
| 1451 | #log('pipe for %s: %d %d', p, r, w)
|
| 1452 | prev = self.procs[-1]
|
| 1453 |
|
| 1454 | prev.AddStateChange(StdoutToPipe(r, w)) # applied on StartPipeline()
|
| 1455 | p.AddStateChange(StdinFromPipe(r, w)) # applied on StartPipeline()
|
| 1456 |
|
| 1457 | p.AddPipeToClose(r, w) # MaybeClosePipe() on StartPipeline()
|
| 1458 |
|
| 1459 | self.procs.append(p)
|
| 1460 |
|
| 1461 | def AddLast(self, thunk):
|
| 1462 | # type: (Tuple[CommandEvaluator, command_t]) -> None
|
| 1463 | """Append the last noden to the pipeline.
|
| 1464 |
|
| 1465 | This is run in the CURRENT process. It is OPTIONAL, because
|
| 1466 | pipelines in the background are run uniformly.
|
| 1467 | """
|
| 1468 | self.last_thunk = thunk
|
| 1469 |
|
| 1470 | assert len(self.procs) != 0
|
| 1471 |
|
| 1472 | r, w = posix.pipe()
|
| 1473 | prev = self.procs[-1]
|
| 1474 | prev.AddStateChange(StdoutToPipe(r, w))
|
| 1475 |
|
| 1476 | self.last_pipe = (r, w) # So we can connect it to last_thunk
|
| 1477 |
|
| 1478 | def StartPipeline(self, waiter):
|
| 1479 | # type: (Waiter) -> None
|
| 1480 |
|
| 1481 | # If we are creating a pipeline in a subshell or we aren't running with job
|
| 1482 | # control, our children should remain in our inherited process group.
|
| 1483 | # the pipelines's group ID.
|
| 1484 | if self.job_control.Enabled():
|
| 1485 | self.pgid = OWN_LEADER # first process in pipeline is the leader
|
| 1486 |
|
| 1487 | for i, proc in enumerate(self.procs):
|
| 1488 | if self.pgid != INVALID_PGID:
|
| 1489 | proc.AddStateChange(SetPgid(self.pgid, self.tracer))
|
| 1490 |
|
| 1491 | # Figure out the pid
|
| 1492 | pid = proc.StartProcess(trace.PipelinePart)
|
| 1493 | if i == 0 and self.pgid != INVALID_PGID:
|
| 1494 | # Mimic bash and use the PID of the FIRST process as the group
|
| 1495 | # for the whole pipeline.
|
| 1496 | self.pgid = pid
|
| 1497 |
|
| 1498 | self.pids.append(pid)
|
| 1499 | self.pipe_status.append(-1) # uninitialized
|
| 1500 |
|
| 1501 | # NOTE: This is done in the SHELL PROCESS after every fork() call.
|
| 1502 | # It can't be done at the end; otherwise processes will have descriptors
|
| 1503 | # from non-adjacent pipes.
|
| 1504 | proc.MaybeClosePipe()
|
| 1505 |
|
| 1506 | if self.last_thunk:
|
| 1507 | self.pipe_status.append(-1) # for self.last_thunk
|
| 1508 |
|
| 1509 | #log('Started pipeline PIDS=%s, pgid=%d', self.pids, self.pgid)
|
| 1510 |
|
| 1511 | def Wait(self, waiter):
|
| 1512 | # type: (Waiter) -> List[int]
|
| 1513 | """Wait for this Pipeline to finish."""
|
| 1514 |
|
| 1515 | assert self.procs, "no procs for Wait()"
|
| 1516 | # waitpid(-1) zero or more times
|
| 1517 | while self.state == job_state_e.Running:
|
| 1518 | # Keep waiting until there's nothing to wait for.
|
| 1519 | result, _ = waiter.WaitForOne()
|
| 1520 | if result == W1_NO_CHILDREN:
|
| 1521 | break
|
| 1522 |
|
| 1523 | return self.pipe_status
|
| 1524 |
|
| 1525 | def JobWait(self, waiter):
|
| 1526 | # type: (Waiter) -> wait_status_t
|
| 1527 | """Pipeline::JobWait(), called by 'wait' builtin, e.g. 'wait %1'."""
|
| 1528 | # wait builtin can be interrupted
|
| 1529 | assert self.procs, "no procs for Wait()"
|
| 1530 | while self.state == job_state_e.Running:
|
| 1531 | result, w1_arg = waiter.WaitForOne()
|
| 1532 |
|
| 1533 | if result == W1_CALL_INTR: # signal
|
| 1534 | return wait_status.Cancelled(w1_arg)
|
| 1535 |
|
| 1536 | if result == W1_NO_CHILDREN:
|
| 1537 | break
|
| 1538 |
|
| 1539 | # Ignore W1_EXITED, W1_STOPPED - these are OTHER processes
|
| 1540 |
|
| 1541 | assert all(st >= 0 for st in self.pipe_status), self.pipe_status
|
| 1542 | return wait_status.Pipeline(self.state, self.pipe_status)
|
| 1543 |
|
| 1544 | def RunLastPart(self, waiter, fd_state):
|
| 1545 | # type: (Waiter, FdState) -> List[int]
|
| 1546 | """Run this pipeline synchronously (foreground pipeline).
|
| 1547 |
|
| 1548 | Returns:
|
| 1549 | pipe_status (list of integers).
|
| 1550 | """
|
| 1551 | assert len(self.pids) == len(self.procs)
|
| 1552 |
|
| 1553 | # TODO: break circular dep. Bit flags could go in ASDL or headers.
|
| 1554 | from osh import cmd_eval
|
| 1555 |
|
| 1556 | # This is tcsetpgrp()
|
| 1557 | # TODO: fix race condition -- I believe the first process could have
|
| 1558 | # stopped already, and thus getpgid() will fail
|
| 1559 | self.job_control.MaybeGiveTerminal(self.pgid)
|
| 1560 |
|
| 1561 | # Run the last part of the pipeline IN PARALLEL with other processes. It
|
| 1562 | # may or may not fork:
|
| 1563 | # echo foo | read line # no fork, the builtin runs in THIS shell process
|
| 1564 | # ls | wc -l # fork for 'wc'
|
| 1565 |
|
| 1566 | cmd_ev, last_node = self.last_thunk
|
| 1567 |
|
| 1568 | assert self.last_pipe is not None
|
| 1569 | r, w = self.last_pipe # set in AddLast()
|
| 1570 | posix.close(w) # we will not write here
|
| 1571 |
|
| 1572 | # Fix lastpipe / job control / DEBUG trap interaction
|
| 1573 | cmd_flags = cmd_eval.NoDebugTrap if self.job_control.Enabled() else 0
|
| 1574 |
|
| 1575 | # The ERR trap only runs for the WHOLE pipeline, not the COMPONENTS in
|
| 1576 | # a pipeline.
|
| 1577 | cmd_flags |= cmd_eval.NoErrTrap
|
| 1578 |
|
| 1579 | io_errors = [] # type: List[int]
|
| 1580 | with ctx_Pipe(fd_state, r, io_errors):
|
| 1581 | cmd_ev.ExecuteAndCatch(last_node, cmd_flags)
|
| 1582 |
|
| 1583 | if len(io_errors):
|
| 1584 | e_die('Error setting up last part of pipeline: %s' %
|
| 1585 | posix.strerror(io_errors[0]))
|
| 1586 |
|
| 1587 | # We won't read anymore. If we don't do this, then 'cat' in 'cat
|
| 1588 | # /dev/urandom | sleep 1' will never get SIGPIPE.
|
| 1589 | posix.close(r)
|
| 1590 |
|
| 1591 | self.pipe_status[-1] = cmd_ev.LastStatus()
|
| 1592 | if self.AllExited():
|
| 1593 | self.state = job_state_e.Exited
|
| 1594 |
|
| 1595 | #log('pipestatus before all have finished = %s', self.pipe_status)
|
| 1596 | return self.Wait(waiter)
|
| 1597 |
|
| 1598 | def AllExited(self):
|
| 1599 | # type: () -> bool
|
| 1600 |
|
| 1601 | # mycpp rewrite: all(status != -1 for status in self.pipe_status)
|
| 1602 | for status in self.pipe_status:
|
| 1603 | if status == -1:
|
| 1604 | return False
|
| 1605 | return True
|
| 1606 |
|
| 1607 | def WhenPartExited(self, pid, status):
|
| 1608 | # type: (int, int) -> None
|
| 1609 | """Called by Process::WhenExited()"""
|
| 1610 | #log('Pipeline WhenExited %d %d', pid, status)
|
| 1611 | i = self.pids.index(pid)
|
| 1612 | assert i != -1, 'Unexpected PID %d' % pid
|
| 1613 |
|
| 1614 | if status == 141 and self.sigpipe_status_ok:
|
| 1615 | status = 0
|
| 1616 |
|
| 1617 | self.pipe_status[i] = status
|
| 1618 | if not self.AllExited():
|
| 1619 | return
|
| 1620 |
|
| 1621 | if self.job_id != -1 and self.in_background:
|
| 1622 | # TODO: ONE condition
|
| 1623 | # "Job might have been brought to the foreground after being
|
| 1624 | # assigned a job ID"
|
| 1625 | if self.exec_opts.interactive():
|
| 1626 | print_stderr('[%%%d] PGID %d Done' %
|
| 1627 | (self.job_id, self.pids[0]))
|
| 1628 |
|
| 1629 | # Status of pipeline is status of last process
|
| 1630 | self.status = self.pipe_status[-1]
|
| 1631 | self.state = job_state_e.Exited
|
| 1632 |
|
| 1633 | if not self.in_background:
|
| 1634 | self.job_control.MaybeTakeTerminal()
|
| 1635 |
|
| 1636 |
|
| 1637 | def _JobStateStr(i):
|
| 1638 | # type: (job_state_t) -> str
|
| 1639 | return job_state_str(i, dot=False)
|
| 1640 |
|
| 1641 |
|
| 1642 | def _GetTtyFd():
|
| 1643 | # type: () -> int
|
| 1644 | """Returns -1 if stdio is not a TTY."""
|
| 1645 | try:
|
| 1646 | return posix.open("/dev/tty", O_NONBLOCK | O_NOCTTY | O_RDWR, 0o666)
|
| 1647 | except (IOError, OSError) as e:
|
| 1648 | return -1
|
| 1649 |
|
| 1650 |
|
| 1651 | class ctx_TerminalControl(object):
|
| 1652 |
|
| 1653 | def __init__(self, job_control, errfmt):
|
| 1654 | # type: (JobControl, ui.ErrorFormatter) -> None
|
| 1655 | job_control.InitJobControl()
|
| 1656 | self.job_control = job_control
|
| 1657 | self.errfmt = errfmt
|
| 1658 |
|
| 1659 | def __enter__(self):
|
| 1660 | # type: () -> None
|
| 1661 | pass
|
| 1662 |
|
| 1663 | def __exit__(self, type, value, traceback):
|
| 1664 | # type: (Any, Any, Any) -> None
|
| 1665 |
|
| 1666 | # Return the TTY to the original owner before exiting.
|
| 1667 | try:
|
| 1668 | self.job_control.MaybeReturnTerminal()
|
| 1669 | except error.FatalRuntime as e:
|
| 1670 | # Don't abort the shell on error, just print a message.
|
| 1671 | self.errfmt.PrettyPrintError(e)
|
| 1672 |
|
| 1673 |
|
| 1674 | class JobControl(object):
|
| 1675 | """Interface to setpgid(), tcsetpgrp(), etc."""
|
| 1676 |
|
| 1677 | def __init__(self):
|
| 1678 | # type: () -> None
|
| 1679 |
|
| 1680 | # The main shell's PID and group ID.
|
| 1681 | self.shell_pid = -1
|
| 1682 | self.shell_pgid = -1
|
| 1683 |
|
| 1684 | # The fd of the controlling tty. Set to -1 when job control is disabled.
|
| 1685 | self.shell_tty_fd = -1
|
| 1686 |
|
| 1687 | # For giving the terminal back to our parent before exiting (if not a login
|
| 1688 | # shell).
|
| 1689 | self.original_tty_pgid = -1
|
| 1690 |
|
| 1691 | def InitJobControl(self):
|
| 1692 | # type: () -> None
|
| 1693 | self.shell_pid = posix.getpid()
|
| 1694 | orig_shell_pgid = posix.getpgid(0)
|
| 1695 | self.shell_pgid = orig_shell_pgid
|
| 1696 | self.shell_tty_fd = _GetTtyFd()
|
| 1697 |
|
| 1698 | # If we aren't the leader of our process group, create a group and mark
|
| 1699 | # ourselves as the leader.
|
| 1700 | if self.shell_pgid != self.shell_pid:
|
| 1701 | try:
|
| 1702 | posix.setpgid(self.shell_pid, self.shell_pid)
|
| 1703 | self.shell_pgid = self.shell_pid
|
| 1704 | except (IOError, OSError) as e:
|
| 1705 | self.shell_tty_fd = -1
|
| 1706 |
|
| 1707 | if self.shell_tty_fd != -1:
|
| 1708 | self.original_tty_pgid = posix.tcgetpgrp(self.shell_tty_fd)
|
| 1709 |
|
| 1710 | # If stdio is a TTY, put the shell's process group in the foreground.
|
| 1711 | try:
|
| 1712 | posix.tcsetpgrp(self.shell_tty_fd, self.shell_pgid)
|
| 1713 | except (IOError, OSError) as e:
|
| 1714 | # We probably aren't in the session leader's process group. Disable job
|
| 1715 | # control.
|
| 1716 | self.shell_tty_fd = -1
|
| 1717 | self.shell_pgid = orig_shell_pgid
|
| 1718 | posix.setpgid(self.shell_pid, self.shell_pgid)
|
| 1719 |
|
| 1720 | def Enabled(self):
|
| 1721 | # type: () -> bool
|
| 1722 | """
|
| 1723 | Only the main shell process should bother with job control functions.
|
| 1724 | """
|
| 1725 | #log('ENABLED? %d', self.shell_tty_fd)
|
| 1726 |
|
| 1727 | # TODO: get rid of getpid()? I think SubProgramThunk should set a
|
| 1728 | # flag.
|
| 1729 | return self.shell_tty_fd != -1 and posix.getpid() == self.shell_pid
|
| 1730 |
|
| 1731 | # TODO: This isn't a PID. This is a process group ID?
|
| 1732 | #
|
| 1733 | # What should the table look like?
|
| 1734 | #
|
| 1735 | # Do we need the last PID? I don't know why bash prints that. Probably so
|
| 1736 | # you can do wait $!
|
| 1737 | # wait -n waits for any node to go from job_state_e.Running to job_state_e.Done?
|
| 1738 | #
|
| 1739 | # And it needs a flag for CURRENT, for the implicit arg to 'fg'.
|
| 1740 | # job_id is just an integer. This is sort of lame.
|
| 1741 | #
|
| 1742 | # [job_id, flag, pgid, job_state, node]
|
| 1743 |
|
| 1744 | def MaybeGiveTerminal(self, pgid):
|
| 1745 | # type: (int) -> None
|
| 1746 | """If stdio is a TTY, move the given process group to the
|
| 1747 | foreground."""
|
| 1748 | if not self.Enabled():
|
| 1749 | # Only call tcsetpgrp when job control is enabled.
|
| 1750 | return
|
| 1751 |
|
| 1752 | try:
|
| 1753 | posix.tcsetpgrp(self.shell_tty_fd, pgid)
|
| 1754 | except (IOError, OSError) as e:
|
| 1755 | e_die('osh: Failed to move process group %d to foreground: %s' %
|
| 1756 | (pgid, pyutil.strerror(e)))
|
| 1757 |
|
| 1758 | def MaybeTakeTerminal(self):
|
| 1759 | # type: () -> None
|
| 1760 | """If stdio is a TTY, return the main shell's process group to the
|
| 1761 | foreground."""
|
| 1762 | self.MaybeGiveTerminal(self.shell_pgid)
|
| 1763 |
|
| 1764 | def MaybeReturnTerminal(self):
|
| 1765 | # type: () -> None
|
| 1766 | """Called before the shell exits."""
|
| 1767 | self.MaybeGiveTerminal(self.original_tty_pgid)
|
| 1768 |
|
| 1769 |
|
| 1770 | class JobList(object):
|
| 1771 | """Global list of jobs, used by a few builtins."""
|
| 1772 |
|
| 1773 | def __init__(self):
|
| 1774 | # type: () -> None
|
| 1775 |
|
| 1776 | # self.child_procs is used by WaitForOne() to call proc.WhenExited()
|
| 1777 | # and proc.WhenStopped().
|
| 1778 | self.child_procs = {} # type: Dict[int, Process]
|
| 1779 |
|
| 1780 | # self.jobs is used by 'wait %1' and 'fg %2'
|
| 1781 | # job_id -> Job
|
| 1782 | self.jobs = {} # type: Dict[int, Job]
|
| 1783 |
|
| 1784 | # self.pid_to_job is used by 'wait -n' and 'wait' - to call
|
| 1785 | # CleanupWhenProcessExits(). They Dict key is job.PidForWait()
|
| 1786 | self.pid_to_job = {} # type: Dict[int, Job]
|
| 1787 |
|
| 1788 | # TODO: consider linear search through JobList
|
| 1789 | # - by job ID
|
| 1790 | # - by PID
|
| 1791 | # - then you don't have to bother as much with the dicts
|
| 1792 | # - you still need the child process dict to set the status and
|
| 1793 | # state?
|
| 1794 |
|
| 1795 | self.debug_pipelines = [] # type: List[Pipeline]
|
| 1796 |
|
| 1797 | # Counter used to assign IDs to jobs. It is incremented every time a job
|
| 1798 | # is created. Once all active jobs are done it is reset to 1. I'm not
|
| 1799 | # sure if this reset behavior is mandated by POSIX, but other shells do
|
| 1800 | # it, so we mimic for the sake of compatibility.
|
| 1801 | self.next_job_id = 1
|
| 1802 |
|
| 1803 | def RegisterJob(self, job):
|
| 1804 | # type: (Job) -> int
|
| 1805 | """Create a background job, which you can wait %2, fg %2, kill %2, etc.
|
| 1806 |
|
| 1807 | - A job is either a Process or Pipeline.
|
| 1808 | - A job is registered in these 2 situations:
|
| 1809 | 1. async: sleep 5 &
|
| 1810 | 2. stopped: sleep 5; then Ctrl-Z
|
| 1811 | That is, in the interactive shell, the foreground process can be
|
| 1812 | receives signals, and can be stopped
|
| 1813 | """
|
| 1814 | job_id = self.next_job_id
|
| 1815 | self.next_job_id += 1
|
| 1816 |
|
| 1817 | # Look up the job by job ID, for wait %1, kill %1, etc.
|
| 1818 | self.jobs[job_id] = job
|
| 1819 |
|
| 1820 | # Pipelines
|
| 1821 | # TODO: register all PIDs? And conversely, remove all PIDs
|
| 1822 | # what do other shells do?
|
| 1823 | self.pid_to_job[job.PidForWait()] = job
|
| 1824 |
|
| 1825 | # Mutate the job itself
|
| 1826 | job.job_id = job_id
|
| 1827 |
|
| 1828 | return job_id
|
| 1829 |
|
| 1830 | def JobFromPid(self, pid):
|
| 1831 | # type: (int) -> Optional[Job]
|
| 1832 | return self.pid_to_job.get(pid)
|
| 1833 |
|
| 1834 | def _MaybeResetCounter(self):
|
| 1835 | # type: () -> None
|
| 1836 | if len(self.jobs) == 0:
|
| 1837 | self.next_job_id = 1
|
| 1838 |
|
| 1839 | def CleanupWhenJobExits(self, job):
|
| 1840 | # type: (Job) -> None
|
| 1841 | """Called when say 'fg %2' exits, and when 'wait %2' exits"""
|
| 1842 | mylib.dict_erase(self.jobs, job.job_id)
|
| 1843 |
|
| 1844 | mylib.dict_erase(self.pid_to_job, job.PidForWait())
|
| 1845 |
|
| 1846 | self._MaybeResetCounter()
|
| 1847 |
|
| 1848 | def CleanupWhenProcessExits(self, pid):
|
| 1849 | # type: (int) -> None
|
| 1850 | """Given a PID, remove the job if it has Exited."""
|
| 1851 |
|
| 1852 | job = self.pid_to_job.get(pid)
|
| 1853 | if 0:
|
| 1854 | # TODO: background pipelines don't clean up properly, because only
|
| 1855 | # the last PID is registered in job_list.pid_to_job
|
| 1856 |
|
| 1857 | # Should we switch to a linear search of a background job array?
|
| 1858 | # Foreground jobs are stored in self.child_procs, and we migrate
|
| 1859 | # between them?
|
| 1860 |
|
| 1861 | log('*** CleanupWhenProcessExits %d', pid)
|
| 1862 | log('job %s', job)
|
| 1863 | #log('STATE %s', _JobStateStr(job.state))
|
| 1864 |
|
| 1865 | if job and job.state == job_state_e.Exited:
|
| 1866 | # Note: only the LAST PID in a pipeline will ever be here, but it's
|
| 1867 | # OK to try to delete it.
|
| 1868 | mylib.dict_erase(self.pid_to_job, pid)
|
| 1869 |
|
| 1870 | mylib.dict_erase(self.jobs, job.job_id)
|
| 1871 |
|
| 1872 | self._MaybeResetCounter()
|
| 1873 |
|
| 1874 | def AddChildProcess(self, pid, proc):
|
| 1875 | # type: (int, Process) -> None
|
| 1876 | """Every child process should be added here as soon as we know its PID.
|
| 1877 |
|
| 1878 | When the Waiter gets an EXITED or STOPPED notification, we need
|
| 1879 | to know about it so 'jobs' can work.
|
| 1880 |
|
| 1881 | Note: this contains Process objects that are part of a Pipeline object.
|
| 1882 | Does it need to?
|
| 1883 | """
|
| 1884 | self.child_procs[pid] = proc
|
| 1885 |
|
| 1886 | def PopChildProcess(self, pid):
|
| 1887 | # type: (int) -> Optional[Process]
|
| 1888 | """Remove the child process with the given PID."""
|
| 1889 | pr = self.child_procs.get(pid)
|
| 1890 | if pr is not None:
|
| 1891 | mylib.dict_erase(self.child_procs, pid)
|
| 1892 | return pr
|
| 1893 |
|
| 1894 | if mylib.PYTHON:
|
| 1895 |
|
| 1896 | def AddPipeline(self, pi):
|
| 1897 | # type: (Pipeline) -> None
|
| 1898 | """For debugging only."""
|
| 1899 | self.debug_pipelines.append(pi)
|
| 1900 |
|
| 1901 | def GetCurrentAndPreviousJobs(self):
|
| 1902 | # type: () -> Tuple[Optional[Job], Optional[Job]]
|
| 1903 | """Return the "current" and "previous" jobs (AKA `%+` and `%-`).
|
| 1904 |
|
| 1905 | See the POSIX specification for the `jobs` builtin for details:
|
| 1906 | https://pubs.opengroup.org/onlinepubs/007904875/utilities/jobs.html
|
| 1907 |
|
| 1908 | IMPORTANT NOTE: This method assumes that the jobs list will not change
|
| 1909 | during its execution! This assumption holds for now because we only ever
|
| 1910 | update the jobs list from the main loop after WaitPid() informs us of a
|
| 1911 | change. If we implement `set -b` and install a signal handler for
|
| 1912 | SIGCHLD we should be careful to synchronize it with this function. The
|
| 1913 | unsafety of mutating GC data structures from a signal handler should
|
| 1914 | make this a non-issue, but if bugs related to this appear this note may
|
| 1915 | be helpful...
|
| 1916 | """
|
| 1917 | # Split all active jobs by state and sort each group by decreasing job
|
| 1918 | # ID to approximate newness.
|
| 1919 | stopped_jobs = [] # type: List[Job]
|
| 1920 | running_jobs = [] # type: List[Job]
|
| 1921 | for i in xrange(0, self.next_job_id):
|
| 1922 | job = self.jobs.get(i, None)
|
| 1923 | if not job:
|
| 1924 | continue
|
| 1925 |
|
| 1926 | if job.state == job_state_e.Stopped:
|
| 1927 | stopped_jobs.append(job)
|
| 1928 |
|
| 1929 | elif job.state == job_state_e.Running:
|
| 1930 | running_jobs.append(job)
|
| 1931 |
|
| 1932 | current = None # type: Optional[Job]
|
| 1933 | previous = None # type: Optional[Job]
|
| 1934 | # POSIX says: If there is any suspended job, then the current job shall
|
| 1935 | # be a suspended job. If there are at least two suspended jobs, then the
|
| 1936 | # previous job also shall be a suspended job.
|
| 1937 | #
|
| 1938 | # So, we will only return running jobs from here if there are no recent
|
| 1939 | # stopped jobs.
|
| 1940 | if len(stopped_jobs) > 0:
|
| 1941 | current = stopped_jobs.pop()
|
| 1942 |
|
| 1943 | if len(stopped_jobs) > 0:
|
| 1944 | previous = stopped_jobs.pop()
|
| 1945 |
|
| 1946 | if len(running_jobs) > 0 and not current:
|
| 1947 | current = running_jobs.pop()
|
| 1948 |
|
| 1949 | if len(running_jobs) > 0 and not previous:
|
| 1950 | previous = running_jobs.pop()
|
| 1951 |
|
| 1952 | if not previous:
|
| 1953 | previous = current
|
| 1954 |
|
| 1955 | return current, previous
|
| 1956 |
|
| 1957 | def JobFromSpec(self, job_spec):
|
| 1958 | # type: (str) -> Optional[Job]
|
| 1959 | """Parse the given job spec and return the matching job. If there is no
|
| 1960 | matching job, this function returns None.
|
| 1961 |
|
| 1962 | See the POSIX spec for the `jobs` builtin for details about job specs:
|
| 1963 | https://pubs.opengroup.org/onlinepubs/007904875/utilities/jobs.html
|
| 1964 | """
|
| 1965 | if job_spec in CURRENT_JOB_SPECS:
|
| 1966 | current, _ = self.GetCurrentAndPreviousJobs()
|
| 1967 | return current
|
| 1968 |
|
| 1969 | if job_spec == '%-':
|
| 1970 | _, previous = self.GetCurrentAndPreviousJobs()
|
| 1971 | return previous
|
| 1972 |
|
| 1973 | #log('** SEARCHING %s', self.jobs)
|
| 1974 | # TODO: Add support for job specs based on prefixes of process argv.
|
| 1975 | m = util.RegexSearch(r'^%([0-9]+)$', job_spec)
|
| 1976 | if m is not None:
|
| 1977 | assert len(m) == 2
|
| 1978 | job_id = int(m[1])
|
| 1979 | if job_id in self.jobs:
|
| 1980 | return self.jobs[job_id]
|
| 1981 |
|
| 1982 | return None
|
| 1983 |
|
| 1984 | def DisplayJobs(self, style):
|
| 1985 | # type: (int) -> None
|
| 1986 | """Used by the 'jobs' builtin.
|
| 1987 |
|
| 1988 | https://pubs.opengroup.org/onlinepubs/9699919799/utilities/jobs.html
|
| 1989 |
|
| 1990 | "By default, the jobs utility shall display the status of all stopped jobs,
|
| 1991 | running background jobs and all jobs whose status has changed and have not
|
| 1992 | been reported by the shell."
|
| 1993 | """
|
| 1994 | # NOTE: A job is a background process or pipeline.
|
| 1995 | #
|
| 1996 | # echo hi | wc -l -- this starts two processes. Wait for TWO
|
| 1997 | # echo hi | wc -l & -- this starts a process which starts two processes
|
| 1998 | # Wait for ONE.
|
| 1999 | #
|
| 2000 | # 'jobs -l' GROUPS the PIDs by job. It has the job number, + - indicators
|
| 2001 | # for %% and %-, PID, status, and "command".
|
| 2002 | #
|
| 2003 | # Every component of a pipeline is on the same line with 'jobs', but
|
| 2004 | # they're separated into different lines with 'jobs -l'.
|
| 2005 | #
|
| 2006 | # See demo/jobs-builtin.sh
|
| 2007 |
|
| 2008 | # $ jobs -l
|
| 2009 | # [1]+ 24414 Stopped sleep 5
|
| 2010 | # 24415 | sleep 5
|
| 2011 | # [2] 24502 Running sleep 6
|
| 2012 | # 24503 | sleep 6
|
| 2013 | # 24504 | sleep 5 &
|
| 2014 | # [3]- 24508 Running sleep 6
|
| 2015 | # 24509 | sleep 6
|
| 2016 | # 24510 | sleep 5 &
|
| 2017 |
|
| 2018 | f = mylib.Stdout()
|
| 2019 | for job_id, job in iteritems(self.jobs):
|
| 2020 | # Use the %1 syntax
|
| 2021 | job.DisplayJob(job_id, f, style)
|
| 2022 |
|
| 2023 | def DebugPrint(self):
|
| 2024 | # type: () -> None
|
| 2025 |
|
| 2026 | f = mylib.Stdout()
|
| 2027 | f.write('\n')
|
| 2028 | f.write('[process debug info]\n')
|
| 2029 |
|
| 2030 | for pid, proc in iteritems(self.child_procs):
|
| 2031 | proc.DisplayJob(-1, f, STYLE_DEFAULT)
|
| 2032 | #p = ' |' if proc.parent_pipeline else ''
|
| 2033 | #print('%d %7s %s%s' % (pid, _JobStateStr(proc.state), proc.thunk.UserString(), p))
|
| 2034 |
|
| 2035 | if len(self.debug_pipelines):
|
| 2036 | f.write('\n')
|
| 2037 | f.write('[pipeline debug info]\n')
|
| 2038 | for pi in self.debug_pipelines:
|
| 2039 | pi.DebugPrint()
|
| 2040 |
|
| 2041 | def ListRecent(self):
|
| 2042 | # type: () -> None
|
| 2043 | """For jobs -n, which I think is also used in the interactive
|
| 2044 | prompt."""
|
| 2045 | pass
|
| 2046 |
|
| 2047 | def NumRunning(self):
|
| 2048 | # type: () -> int
|
| 2049 | """Return the number of running jobs.
|
| 2050 |
|
| 2051 | Used by 'wait' and 'wait -n'.
|
| 2052 | """
|
| 2053 | count = 0
|
| 2054 | for _, job in iteritems(self.jobs): # mycpp rewrite: from itervalues()
|
| 2055 | if job.State() == job_state_e.Running:
|
| 2056 | count += 1
|
| 2057 | return count
|
| 2058 |
|
| 2059 |
|
| 2060 | # Some WaitForOne() return values, which are negative. The numbers are
|
| 2061 | # arbitrary negative numbers.
|
| 2062 | #
|
| 2063 | # They don't overlap with iolib.UNTRAPPED_SIGWINCH == -10
|
| 2064 | # which LastSignal() can return
|
| 2065 |
|
| 2066 | W1_EXITED = -11 # process exited
|
| 2067 | W1_STOPPED = -12 # process was stopped
|
| 2068 | W1_CALL_INTR = -15 # the waitpid(-1) call was interrupted
|
| 2069 |
|
| 2070 | W1_NO_CHILDREN = -13 # no child processes to wait for
|
| 2071 | W1_NO_CHANGE = -14 # WNOHANG was passed and there were no state changes
|
| 2072 |
|
| 2073 | NO_ARG = -20
|
| 2074 |
|
| 2075 |
|
| 2076 |
|
| 2077 |
|
| 2078 |
|
| 2079 | def GetSignalMessage(sig_num):
|
| 2080 | # type: (int) -> Optional[str]
|
| 2081 | """Get signal message from libc."""
|
| 2082 | return libc.strsignal(sig_num)
|
| 2083 |
|
| 2084 |
|
| 2085 | class Waiter(object):
|
| 2086 | """A capability to wait for processes.
|
| 2087 |
|
| 2088 | This must be a singleton (and is because CommandEvaluator is a singleton).
|
| 2089 |
|
| 2090 | Invariants:
|
| 2091 | - Every child process is registered once
|
| 2092 | - Every child process is waited for
|
| 2093 |
|
| 2094 | Canonical example of why we need a GLOBAL waiter:
|
| 2095 |
|
| 2096 | { sleep 3; echo 'done 3'; } &
|
| 2097 | { sleep 4; echo 'done 4'; } &
|
| 2098 |
|
| 2099 | # ... do arbitrary stuff ...
|
| 2100 |
|
| 2101 | { sleep 1; exit 1; } | { sleep 2; exit 2; }
|
| 2102 |
|
| 2103 | Now when you do wait() after starting the pipeline, you might get a pipeline
|
| 2104 | process OR a background process! So you have to distinguish between them.
|
| 2105 | """
|
| 2106 |
|
| 2107 | def __init__(self, job_list, exec_opts, signal_safe, tracer):
|
| 2108 | # type: (JobList, optview.Exec, iolib.SignalSafe, dev.Tracer) -> None
|
| 2109 | self.job_list = job_list
|
| 2110 | self.exec_opts = exec_opts
|
| 2111 | self.signal_safe = signal_safe
|
| 2112 | self.tracer = tracer
|
| 2113 | self.last_status = 127 # wait -n error code
|
| 2114 |
|
| 2115 | def LastStatusCode(self):
|
| 2116 | # type: () -> int
|
| 2117 | """Returns exit code for wait -n"""
|
| 2118 | return self.last_status
|
| 2119 |
|
| 2120 | def WaitForOne(self, waitpid_options=0):
|
| 2121 | # type: (int) -> Tuple[int, int]
|
| 2122 | """Wait until the next process returns (or maybe Ctrl-C).
|
| 2123 |
|
| 2124 | Returns:
|
| 2125 | One of these negative numbers:
|
| 2126 | W1_NO_CHILDREN Nothing to wait for
|
| 2127 | W1_NO_CHANGE no state changes when WNOHANG passed - used by
|
| 2128 | main loop
|
| 2129 | W1_EXITED Process exited (with or without signal)
|
| 2130 | W1_STOPPED Process stopped
|
| 2131 | W1_CALL_INTR
|
| 2132 | UNTRAPPED_SIGWINCH
|
| 2133 | Or
|
| 2134 | result > 0 Signal that waitpid() was interrupted with
|
| 2135 |
|
| 2136 | In the interactive shell, we return 0 if we get a Ctrl-C, so the caller
|
| 2137 | will try again.
|
| 2138 |
|
| 2139 | Callers:
|
| 2140 | wait -n -- loop until there is one fewer process (TODO)
|
| 2141 | wait -- loop until there are no processes
|
| 2142 | wait $! -- loop until job state is Done (process or pipeline)
|
| 2143 | Process::Wait() -- loop until Process state is done
|
| 2144 | Pipeline::Wait() -- loop until Pipeline state is done
|
| 2145 |
|
| 2146 | Comparisons:
|
| 2147 | bash: jobs.c waitchld() Has a special case macro(!) CHECK_WAIT_INTR for
|
| 2148 | the wait builtin
|
| 2149 |
|
| 2150 | dash: jobs.c waitproc() uses sigfillset(), sigprocmask(), etc. Runs in a
|
| 2151 | loop while (gotsigchld), but that might be a hack for System V!
|
| 2152 |
|
| 2153 | Should we have a cleaner API like posix::wait_for_one() ?
|
| 2154 |
|
| 2155 | wait_result =
|
| 2156 | NoChildren -- ECHILD - no more
|
| 2157 | | Exited(int pid) -- process done - call job_list.PopStatus() for status
|
| 2158 | # do we also we want ExitedWithSignal() ?
|
| 2159 | | Stopped(int pid)
|
| 2160 | | Interrupted(int sig_num) -- may or may not retry
|
| 2161 | | UntrappedSigwinch -- ignored
|
| 2162 |
|
| 2163 | | NoChange -- for WNOHANG - is this a different API?
|
| 2164 | """
|
| 2165 | #waitpid_options |= WCONTINUED
|
| 2166 | pid, status = pyos.WaitPid(waitpid_options)
|
| 2167 | if pid == 0:
|
| 2168 | return W1_NO_CHANGE, NO_ARG # WNOHANG passed, and no state changes
|
| 2169 |
|
| 2170 | if pid < 0: # error case
|
| 2171 | err_num = status
|
| 2172 | #log('waitpid() error => %d %s', e.errno, pyutil.strerror(e))
|
| 2173 | if err_num == ECHILD:
|
| 2174 | return W1_NO_CHILDREN, NO_ARG
|
| 2175 |
|
| 2176 | if err_num == EINTR: # Bug #858 fix
|
| 2177 | # e.g. 1 for SIGHUP, or also be UNTRAPPED_SIGWINCH == -1
|
| 2178 | last_sig = self.signal_safe.LastSignal()
|
| 2179 | if last_sig == iolib.UNTRAPPED_SIGWINCH:
|
| 2180 | return iolib.UNTRAPPED_SIGWINCH, NO_ARG
|
| 2181 | else:
|
| 2182 | return W1_CALL_INTR, last_sig
|
| 2183 |
|
| 2184 | # No other errors? Man page says waitpid(INT_MIN) == ESRCH, "no
|
| 2185 | # such process", an invalid PID
|
| 2186 | raise AssertionError()
|
| 2187 |
|
| 2188 | # All child processes are supposed to be in this dict. Even if a
|
| 2189 | # grandchild outlives the child (its parent), the shell does NOT become
|
| 2190 | # the parent. The init process does.
|
| 2191 | proc = self.job_list.child_procs.get(pid)
|
| 2192 |
|
| 2193 | if proc is None and self.exec_opts.verbose_warn():
|
| 2194 | print_stderr("oils: PID %d exited, but oils didn't start it" % pid)
|
| 2195 |
|
| 2196 | if 0:
|
| 2197 | self.job_list.DebugPrint()
|
| 2198 |
|
| 2199 | was_stopped = False
|
| 2200 | if WIFSIGNALED(status):
|
| 2201 | term_sig = WTERMSIG(status)
|
| 2202 | status = 128 + term_sig
|
| 2203 |
|
| 2204 | # Print newline after Ctrl-C.
|
| 2205 | if term_sig == SIGINT:
|
| 2206 | print('')
|
| 2207 | else:
|
| 2208 | msg = GetSignalMessage(term_sig)
|
| 2209 | if msg is not None:
|
| 2210 | # WCOREDUMP checks if process dumped core
|
| 2211 | # On systems without WCOREDUMP, this will be False
|
| 2212 | if WCOREDUMP(status):
|
| 2213 | msg = msg + ' (core dumped)'
|
| 2214 | print_stderr(msg)
|
| 2215 |
|
| 2216 | if proc:
|
| 2217 | proc.WhenExited(pid, status)
|
| 2218 |
|
| 2219 | elif WIFEXITED(status):
|
| 2220 | status = WEXITSTATUS(status)
|
| 2221 | if proc:
|
| 2222 | proc.WhenExited(pid, status)
|
| 2223 |
|
| 2224 | elif WIFSTOPPED(status):
|
| 2225 | was_stopped = True
|
| 2226 |
|
| 2227 | stop_sig = WSTOPSIG(status)
|
| 2228 |
|
| 2229 | if proc:
|
| 2230 | proc.WhenStopped(stop_sig)
|
| 2231 |
|
| 2232 | # This would be more consistent, but it's an extension to POSIX
|
| 2233 | #elif WIFCONTINUED(status):
|
| 2234 | # if proc:
|
| 2235 | # proc.WhenContinued()
|
| 2236 |
|
| 2237 | else:
|
| 2238 | raise AssertionError(status)
|
| 2239 |
|
| 2240 | self.last_status = status # for wait -n
|
| 2241 | self.tracer.OnProcessEnd(pid, status)
|
| 2242 |
|
| 2243 | if was_stopped:
|
| 2244 | return W1_STOPPED, pid
|
| 2245 | else:
|
| 2246 | return W1_EXITED, pid
|
| 2247 |
|
| 2248 | def PollForEvents(self):
|
| 2249 | # type: () -> None
|
| 2250 | """For the interactive shell to print when processes have exited."""
|
| 2251 | while True:
|
| 2252 | result, _ = self.WaitForOne(waitpid_options=WNOHANG)
|
| 2253 |
|
| 2254 | if result == W1_NO_CHANGE:
|
| 2255 | break
|
| 2256 | if result == W1_NO_CHILDREN:
|
| 2257 | break
|
| 2258 |
|
| 2259 | # Keep polling here
|
| 2260 | assert result in (W1_EXITED, W1_STOPPED), result
|
| 2261 | # W1_CALL_INTR and iolib.UNTRAPPED_SIGWINCH should not happen,
|
| 2262 | # because WNOHANG is a non-blocking call
|