1 | /* Copyright (C) 1993-2022 Free Software Foundation, Inc. |
2 | This file is part of the GNU C Library. |
3 | |
4 | The GNU C Library is free software; you can redistribute it and/or |
5 | modify it under the terms of the GNU Lesser General Public |
6 | License as published by the Free Software Foundation; either |
7 | version 2.1 of the License, or (at your option) any later version. |
8 | |
9 | The GNU C Library is distributed in the hope that it will be useful, |
10 | but WITHOUT ANY WARRANTY; without even the implied warranty of |
11 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
12 | Lesser General Public License for more details. |
13 | |
14 | You should have received a copy of the GNU Lesser General Public |
15 | License along with the GNU C Library; if not, see |
16 | <https://www.gnu.org/licenses/>. */ |
17 | |
18 | #include <sys/types.h> |
19 | #include <sys/wait.h> |
20 | #include <errno.h> |
21 | #include <hurd.h> |
22 | #include <hurd/port.h> |
23 | #include <sysdep-cancel.h> |
24 | |
25 | pid_t |
26 | __wait4 (pid_t pid, int *stat_loc, int options, struct rusage *usage) |
27 | { |
28 | pid_t dead; |
29 | error_t err; |
30 | struct rusage ignored; |
31 | int sigcode; |
32 | int dummy; |
33 | int cancel_oldtype; |
34 | |
35 | cancel_oldtype = LIBC_CANCEL_ASYNC(); |
36 | err = __USEPORT_CANCEL (PROC, __proc_wait (port, pid, options, |
37 | stat_loc ?: &dummy, &sigcode, |
38 | usage ?: &ignored, &dead)); |
39 | LIBC_CANCEL_RESET (cancel_oldtype); |
40 | switch (err) |
41 | { |
42 | case 0: /* Got a child. */ |
43 | return dead; |
44 | case EAGAIN: |
45 | /* The RPC returns this error when the WNOHANG flag is set and no |
46 | selected children are dead (but some are living). In that |
47 | situation, our return value is zero. (The RPC can't return zero |
48 | for DEAD without also returning some garbage for the other out |
49 | parameters, so an error return is much more natural here. Hence |
50 | the difference between the RPC and the POSIX.1 interface. */ |
51 | return (pid_t) 0; |
52 | default: |
53 | return (pid_t) __hurd_fail (err); |
54 | } |
55 | } |
56 | |
57 | libc_hidden_def (__wait4) |
58 | weak_alias (__wait4, wait4) |
59 | |