1/* Copyright (C) 1991-2022 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 <errno.h>
19#include <sys/types.h>
20#include <signal.h>
21#include <hurd.h>
22#include <hurd/port.h>
23#include <hurd/signal.h>
24#include <hurd/msg.h>
25
26/* Send a `sig_post' RPC to process number PID. If PID is zero,
27 send the message to all processes in the current process's process group.
28 If PID is < -1, send SIG to all processes in process group - PID.
29 SIG and REFPORT are passed along in the request message. */
30error_t
31_hurd_sig_post (pid_t pid, int sig, mach_port_t arg_refport)
32{
33 int delivered = 0; /* Set when we deliver any signal. */
34 error_t err;
35 mach_port_t proc;
36 struct hurd_userlink ulink;
37
38 inline void kill_pid (pid_t pid) /* Kill one PID. */
39 {
40 err = HURD_MSGPORT_RPC (__proc_getmsgport (proc, pid, &msgport),
41 (refport = arg_refport, 0), 0,
42 /* If no message port we cannot send signals. */
43 msgport == MACH_PORT_NULL ? EPERM
44 : __msg_sig_post (msgport, sig, 0, refport));
45 if (! err)
46 delivered = 1;
47 }
48
49 proc = _hurd_port_get (&_hurd_ports[INIT_PORT_PROC], &ulink);
50
51 if (pid <= 0)
52 {
53 /* Send SIG to each process in pgrp (- PID). */
54 mach_msg_type_number_t npids = 10, i;
55 pid_t pidsbuf[10], *pids = pidsbuf;
56
57 err = __proc_getpgrppids (proc, - pid, &pids, &npids);
58 if (!err)
59 {
60 int self = 0;
61 for (i = 0; i < npids; ++i)
62 if (pids[i] == _hurd_pid)
63 /* We must do ourselves last so we are not suspended
64 and fail to suspend the other processes in the pgrp. */
65 self = 1;
66 else
67 {
68 kill_pid (pids[i]);
69 if (err == ESRCH)
70 /* The process died already. Ignore it. */
71 err = 0;
72 }
73 if (pids != pidsbuf)
74 __vm_deallocate (__mach_task_self (),
75 (vm_address_t) pids, npids * sizeof (pids[0]));
76
77 if (self)
78 kill_pid (_hurd_pid);
79 }
80 }
81 else
82 kill_pid (pid);
83
84 _hurd_port_free (&_hurd_ports[INIT_PORT_PROC], &ulink, proc);
85
86 /* If we delivered no signals, but ERR is clear, this must mean that
87 every kill_pid call failed with ESRCH, meaning all the processes in
88 the pgrp died between proc_getpgrppids and kill_pid; in that case we
89 fail with ESRCH. */
90 return delivered ? 0 : err ?: ESRCH;
91}
92weak_alias (_hurd_sig_post, hurd_sig_post)
93

source code of glibc/hurd/hurdkill.c