1 | /* _hurd_ctty_input -- Do an input RPC and generate SIGTTIN if necessary. |
2 | Copyright (C) 1995-2022 Free Software Foundation, Inc. |
3 | This file is part of the GNU C Library. |
4 | |
5 | The GNU C Library is free software; you can redistribute it and/or |
6 | modify it under the terms of the GNU Lesser General Public |
7 | License as published by the Free Software Foundation; either |
8 | version 2.1 of the License, or (at your option) any later version. |
9 | |
10 | The GNU C Library is distributed in the hope that it will be useful, |
11 | but WITHOUT ANY WARRANTY; without even the implied warranty of |
12 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
13 | Lesser General Public License for more details. |
14 | |
15 | You should have received a copy of the GNU Lesser General Public |
16 | License along with the GNU C Library; if not, see |
17 | <https://www.gnu.org/licenses/>. */ |
18 | |
19 | #include <hurd.h> |
20 | #include <hurd/signal.h> |
21 | |
22 | /* Call *RPC on PORT and/or CTTY. If a call on CTTY returns EBACKGROUND, |
23 | generate SIGTTIN or EIO as appropriate. */ |
24 | |
25 | error_t |
26 | _hurd_ctty_input (io_t port, io_t ctty, error_t (*rpc) (io_t)) |
27 | { |
28 | error_t err; |
29 | |
30 | if (ctty == MACH_PORT_NULL) |
31 | return (*rpc) (port); |
32 | |
33 | do |
34 | { |
35 | err = (*rpc) (ctty); |
36 | if (err == EBACKGROUND) |
37 | { |
38 | /* We are a background job and tried to read from the tty. |
39 | We should probably get a SIGTTIN signal. */ |
40 | if (_hurd_orphaned) |
41 | /* Our process group is orphaned. Don't stop; just fail. */ |
42 | err = EIO; |
43 | else |
44 | { |
45 | struct hurd_sigstate *ss = _hurd_self_sigstate (); |
46 | struct sigaction *actions; |
47 | |
48 | _hurd_sigstate_lock (ss); |
49 | actions = _hurd_sigstate_actions (ss); |
50 | if (__sigismember (set: &ss->blocked, SIGTTIN) |
51 | || actions[SIGTTIN].sa_handler == SIG_IGN) |
52 | /* We are blocking or ignoring SIGTTIN. Just fail. */ |
53 | err = EIO; |
54 | _hurd_sigstate_unlock (ss); |
55 | |
56 | if (err == EBACKGROUND) |
57 | { |
58 | /* Send a SIGTTIN signal to our process group. |
59 | |
60 | We must remember here not to clobber ERR, since |
61 | the loop condition below uses it to recall that |
62 | we should retry after a stop. */ |
63 | |
64 | __USEPORT (CTTYID, _hurd_sig_post (0, SIGTTIN, port)); |
65 | /* XXX what to do if error here? */ |
66 | |
67 | /* At this point we should have just run the handler for |
68 | SIGTTIN or resumed after being stopped. Now this is |
69 | still a "system call", so check to see if we should |
70 | restart it. */ |
71 | _hurd_sigstate_lock (ss); |
72 | actions = _hurd_sigstate_actions (ss); |
73 | if (!(actions[SIGTTIN].sa_flags & SA_RESTART)) |
74 | err = EINTR; |
75 | _hurd_sigstate_unlock (ss); |
76 | } |
77 | } |
78 | } |
79 | /* If the last RPC generated a SIGTTIN, loop to try it again. */ |
80 | } while (err == EBACKGROUND); |
81 | |
82 | return err; |
83 | } |
84 | |