1 #ifndef HEADER_CURL_SIGPIPE_H
2 #define HEADER_CURL_SIGPIPE_H
3 /***************************************************************************
4 * _ _ ____ _
5 * Project ___| | | | _ \| |
6 * / __| | | | |_) | |
7 * | (__| |_| | _ <| |___
8 * \___|\___/|_| \_\_____|
9 *
10 * Copyright (C) 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 * SPDX-License-Identifier: curl
24 *
25 ***************************************************************************/
26 #include "curl_setup.h"
27
28 #if defined(HAVE_SIGACTION) && \
29 (defined(USE_OPENSSL) || defined(USE_MBEDTLS) || defined(USE_WOLFSSL))
30 #include <signal.h>
31
32 struct sigpipe_ignore {
33 struct sigaction old_pipe_act;
34 bool no_signal;
35 };
36
37 #define SIGPIPE_VARIABLE(x) struct sigpipe_ignore x
38 #define SIGPIPE_MEMBER(x) struct sigpipe_ignore x
39
sigpipe_init(struct sigpipe_ignore * ig)40 static void sigpipe_init(struct sigpipe_ignore *ig)
41 {
42 memset(ig, 0, sizeof(*ig));
43 ig->no_signal = TRUE;
44 }
45
46 /*
47 * sigpipe_ignore() makes sure we ignore SIGPIPE while running libcurl
48 * internals, and then sigpipe_restore() will restore the situation when we
49 * return from libcurl again.
50 */
sigpipe_ignore(struct Curl_easy * data,struct sigpipe_ignore * ig)51 static void sigpipe_ignore(struct Curl_easy *data,
52 struct sigpipe_ignore *ig)
53 {
54 /* get a local copy of no_signal because the Curl_easy might not be
55 around when we restore */
56 ig->no_signal = data->set.no_signal;
57 if(!data->set.no_signal) {
58 struct sigaction action;
59 /* first, extract the existing situation */
60 sigaction(SIGPIPE, NULL, &ig->old_pipe_act);
61 action = ig->old_pipe_act;
62 /* ignore this signal */
63 action.sa_handler = SIG_IGN;
64 sigaction(SIGPIPE, &action, NULL);
65 }
66 }
67
68 /*
69 * sigpipe_restore() puts back the outside world's opinion of signal handler
70 * and SIGPIPE handling. It MUST only be called after a corresponding
71 * sigpipe_ignore() was used.
72 */
sigpipe_restore(struct sigpipe_ignore * ig)73 static void sigpipe_restore(struct sigpipe_ignore *ig)
74 {
75 if(!ig->no_signal)
76 /* restore the outside state */
77 sigaction(SIGPIPE, &ig->old_pipe_act, NULL);
78 }
79
sigpipe_apply(struct Curl_easy * data,struct sigpipe_ignore * ig)80 static void sigpipe_apply(struct Curl_easy *data,
81 struct sigpipe_ignore *ig)
82 {
83 if(data->set.no_signal != ig->no_signal) {
84 sigpipe_restore(ig);
85 sigpipe_ignore(data, ig);
86 }
87 }
88
89 #else
90 /* for systems without sigaction */
91 #define sigpipe_ignore(x,y) Curl_nop_stmt
92 #define sigpipe_apply(x,y) Curl_nop_stmt
93 #define sigpipe_init(x) Curl_nop_stmt
94 #define sigpipe_restore(x) Curl_nop_stmt
95 #define SIGPIPE_VARIABLE(x)
96 #define SIGPIPE_MEMBER(x) bool x
97 #endif
98
99 #endif /* HEADER_CURL_SIGPIPE_H */
100
