1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166
|
/* Pseudo implementation of waitid.
Copyright (C) 1997-2016 Free Software Foundation, Inc.
This file is part of the GNU C Library.
Contributed by Zack Weinberg <zack@rabi.phys.columbia.edu>, 1997.
The GNU C Library is free software; you can redistribute it and/or
modify it under the terms of the GNU Lesser General Public
License as published by the Free Software Foundation; either
version 2.1 of the License, or (at your option) any later version.
The GNU C Library is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
Lesser General Public License for more details.
You should have received a copy of the GNU Lesser General Public
License along with the GNU C Library; if not, see
<http://www.gnu.org/licenses/>. */
#include <assert.h>
#include <errno.h>
#include <signal.h>
#define __need_NULL
#include <stddef.h>
#include <sys/wait.h>
#include <sys/types.h>
#include <sysdep-cancel.h>
#ifdef DO_WAITID
# define OUR_WAITID DO_WAITID
#elif !defined NO_DO_WAITID
# define OUR_WAITID do_waitid
#endif
#ifdef OUR_WAITID
static int
OUR_WAITID (idtype_t idtype, id_t id, siginfo_t *infop, int options)
{
pid_t pid, child;
int status;
switch (idtype)
{
case P_PID:
if(id <= 0)
goto invalid;
pid = (pid_t) id;
break;
case P_PGID:
if (id < 0 || id == 1)
goto invalid;
pid = (pid_t) -id;
break;
case P_ALL:
pid = -1;
break;
default:
invalid:
__set_errno (EINVAL);
return -1;
}
/* Technically we're supposed to return EFAULT if infop is bogus,
but that would involve mucking with signals, which is
too much hassle. User will have to deal with SIGSEGV/SIGBUS.
We just check for a null pointer. */
if (infop == NULL)
{
__set_errno (EFAULT);
return -1;
}
/* This emulation using waitpid cannot support the waitid modes in which
we do not reap the child, or match only stopped and not dead children. */
if (0
#ifdef WNOWAIT
|| (options & WNOWAIT)
#endif
#ifdef WEXITED
|| ((options & (WEXITED|WSTOPPED|WCONTINUED))
!= (WEXITED | (options & WSTOPPED)))
#endif
)
{
__set_errno (ENOTSUP);
return -1;
}
/* Note the waitid() is a cancellation point. But since we call
waitpid() which itself is a cancellation point we do not have
to do anything here. */
child = __waitpid (pid, &status,
options
#ifdef WEXITED
&~ WEXITED
#endif
);
if (child == -1)
/* `waitpid' set `errno' for us. */
return -1;
if (child == 0)
{
/* The WHOHANG bit in OPTIONS is set and there are children available
but none has a status for us. The XPG docs do not mention this
case so we clear the `siginfo_t' struct and return successfully. */
infop->si_signo = 0;
infop->si_code = 0;
return 0;
}
/* Decode the status field and set infop members... */
infop->si_signo = SIGCHLD;
infop->si_pid = child;
infop->si_errno = 0;
if (WIFEXITED (status))
{
infop->si_code = CLD_EXITED;
infop->si_status = WEXITSTATUS (status);
}
else if (WIFSIGNALED (status))
{
infop->si_code = WCOREDUMP (status) ? CLD_DUMPED : CLD_KILLED;
infop->si_status = WTERMSIG (status);
}
else if (WIFSTOPPED (status))
{
infop->si_code = CLD_STOPPED;
infop->si_status = WSTOPSIG (status);
}
#ifdef WIFCONTINUED
else if (WIFCONTINUED (status))
{
infop->si_code = CLD_CONTINUED;
infop->si_status = SIGCONT;
}
#endif
else
/* Can't happen. */
assert (! "What?");
return 0;
}
#endif
int
__waitid (idtype_t idtype, id_t id, siginfo_t *infop, int options)
{
if (SINGLE_THREAD_P)
return do_waitid (idtype, id, infop, options);
int oldtype = LIBC_CANCEL_ASYNC ();
int result = do_waitid (idtype, id, infop, options);
LIBC_CANCEL_RESET (oldtype);
return result;
}
weak_alias (__waitid, waitid)
strong_alias (__waitid, __libc_waitid)
|