1 | /* Common definition for tst-cancel4_* tests. |
2 | |
3 | Copyright (C) 2016-2022 Free Software Foundation, Inc. |
4 | This file is part of the GNU C Library. |
5 | |
6 | The GNU C Library is free software; you can redistribute it and/or |
7 | modify it under the terms of the GNU Lesser General Public |
8 | License as published by the Free Software Foundation; either |
9 | version 2.1 of the License, or (at your option) any later version. |
10 | |
11 | The GNU C Library is distributed in the hope that it will be useful, |
12 | but WITHOUT ANY WARRANTY; without even the implied warranty of |
13 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
14 | Lesser General Public License for more details. |
15 | |
16 | You should have received a copy of the GNU Lesser General Public |
17 | License along with the GNU C Library; if not, see |
18 | <https://www.gnu.org/licenses/>. */ |
19 | |
20 | #include <pthread.h> |
21 | |
22 | #include <support/check.h> |
23 | #include <support/xthread.h> |
24 | #include <support/xunistd.h> |
25 | |
26 | /* Pipe descriptors. */ |
27 | static int fds[2]; |
28 | |
29 | /* Temporary file descriptor, to be closed after each round. */ |
30 | static int tempfd = -1; |
31 | static int tempfd2 = -1; |
32 | /* Name of temporary file to be removed after each round. */ |
33 | static char *tempfname; |
34 | /* Temporary message queue. */ |
35 | static int tempmsg = -1; |
36 | |
37 | /* Often used barrier for two threads. */ |
38 | static pthread_barrier_t b2; |
39 | |
40 | /* The WRITE_BUFFER_SIZE value needs to be chosen such that if we set |
41 | the socket send buffer size to '1', a write of this size on that |
42 | socket will block. |
43 | |
44 | The Linux kernel imposes a minimum send socket buffer size which |
45 | has changed over the years. As of Linux 3.10 the value is: |
46 | |
47 | 2 * (2048 + SKB_DATA_ALIGN(sizeof(struct sk_buff))) |
48 | |
49 | which is attempting to make sure that with standard MTUs, |
50 | TCP can always queue up at least 2 full sized packets. |
51 | |
52 | Furthermore, there is logic in the socket send paths that |
53 | will allow one more packet (of any size) to be queued up as |
54 | long as some socket buffer space remains. Blocking only |
55 | occurs when we try to queue up a new packet and the send |
56 | buffer space has already been fully consumed. |
57 | |
58 | Therefore we must set this value to the largest possible value of |
59 | the formula above (and since it depends upon the size of "struct |
60 | sk_buff", it is dependent upon machine word size etc.) plus some |
61 | slack space. */ |
62 | |
63 | #define WRITE_BUFFER_SIZE 16384 |
64 | |
65 | /* Set the send buffer of socket S to 1 byte so any send operation |
66 | done with WRITE_BUFFER_SIZE bytes will force syscall blocking. */ |
67 | static void |
68 | set_socket_buffer (int s) |
69 | { |
70 | int val = 1; |
71 | socklen_t len = sizeof (val); |
72 | |
73 | TEST_VERIFY_EXIT (setsockopt (s, SOL_SOCKET, SO_SNDBUF, &val, |
74 | sizeof (val)) == 0); |
75 | TEST_VERIFY_EXIT (getsockopt (s, SOL_SOCKET, SO_SNDBUF, &val, &len) == 0); |
76 | TEST_VERIFY_EXIT (val < WRITE_BUFFER_SIZE); |
77 | printf(format: "got size %d\n" , val); |
78 | } |
79 | |
80 | /* Cleanup handling test. */ |
81 | static int cl_called; |
82 | |
83 | static void |
84 | cl (void *arg) |
85 | { |
86 | ++cl_called; |
87 | } |
88 | |
89 | /* Named pipe used to check for blocking open. It should be closed |
90 | after the cancellation handling. */ |
91 | static char fifoname[] = "/tmp/tst-cancel4-fifo-XXXXXX" ; |
92 | static int fifofd; |
93 | |
94 | static void |
95 | __attribute__ ((used)) |
96 | cl_fifo (void *arg) |
97 | { |
98 | ++cl_called; |
99 | |
100 | unlink (name: fifoname); |
101 | close (fd: fifofd); |
102 | fifofd = -1; |
103 | } |
104 | |
105 | struct cancel_tests |
106 | { |
107 | const char *name; |
108 | void *(*tf) (void *); |
109 | int nb; |
110 | int only_early; |
111 | }; |
112 | #define ADD_TEST(name, nbar, early) { #name, tf_##name, nbar, early } |
113 | |