1#ifndef HEADER_CURL_SIGPIPE_H
2#define HEADER_CURL_SIGPIPE_H
3/***************************************************************************
4 * _ _ ____ _
5 * Project ___| | | | _ \| |
6 * / __| | | | |_) | |
7 * | (__| |_| | _ <| |___
8 * \___|\___/|_| \_\_____|
9 *
10 * Copyright (C) 1998 - 2021, Daniel Stenberg, <daniel@haxx.se>, et al.
11 *
12 * This software is licensed as described in the file COPYING, which
13 * you should have received as part of this distribution. The terms
14 * are also available at https://curl.se/docs/copyright.html.
15 *
16 * You may opt to use, copy, modify, merge, publish, distribute and/or sell
17 * copies of the Software, and permit persons to whom the Software is
18 * furnished to do so, under the terms of the COPYING file.
19 *
20 * This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY
21 * KIND, either express or implied.
22 *
23 ***************************************************************************/
24#include "curl_setup.h"
25
26#if defined(HAVE_SIGNAL_H) && defined(HAVE_SIGACTION) && \
27 (defined(USE_OPENSSL) || defined(USE_MBEDTLS) || defined(USE_WOLFSSL))
28#include <signal.h>
29
30struct sigpipe_ignore {
31 struct sigaction old_pipe_act;
32 bool no_signal;
33};
34
35#define SIGPIPE_VARIABLE(x) struct sigpipe_ignore x
36
37/*
38 * sigpipe_ignore() makes sure we ignore SIGPIPE while running libcurl
39 * internals, and then sigpipe_restore() will restore the situation when we
40 * return from libcurl again.
41 */
42static void sigpipe_ignore(struct Curl_easy *data,
43 struct sigpipe_ignore *ig)
44{
45 /* get a local copy of no_signal because the Curl_easy might not be
46 around when we restore */
47 ig->no_signal = data->set.no_signal;
48 if(!data->set.no_signal) {
49 struct sigaction action;
50 /* first, extract the existing situation */
51 memset(&ig->old_pipe_act, 0, sizeof(struct sigaction));
52 sigaction(SIGPIPE, NULL, &ig->old_pipe_act);
53 action = ig->old_pipe_act;
54 /* ignore this signal */
55 action.sa_handler = SIG_IGN;
56 sigaction(SIGPIPE, &action, NULL);
57 }
58}
59
60/*
61 * sigpipe_restore() puts back the outside world's opinion of signal handler
62 * and SIGPIPE handling. It MUST only be called after a corresponding
63 * sigpipe_ignore() was used.
64 */
65static void sigpipe_restore(struct sigpipe_ignore *ig)
66{
67 if(!ig->no_signal)
68 /* restore the outside state */
69 sigaction(SIGPIPE, &ig->old_pipe_act, NULL);
70}
71
72#else
73/* for systems without sigaction */
74#define sigpipe_ignore(x,y) Curl_nop_stmt
75#define sigpipe_restore(x) Curl_nop_stmt
76#define SIGPIPE_VARIABLE(x)
77#endif
78
79#endif /* HEADER_CURL_SIGPIPE_H */
80