1 | /* Copyright (C) 2002-2024 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 <pthread.h> |
20 | #include <stdint.h> |
21 | #include <stdio.h> |
22 | #include <stdlib.h> |
23 | #include <string.h> |
24 | #include <unistd.h> |
25 | #include <sys/mman.h> |
26 | #include <sys/wait.h> |
27 | |
28 | |
29 | static int |
30 | do_test (void) |
31 | { |
32 | size_t ps = sysconf (_SC_PAGESIZE); |
33 | char tmpfname[] = "/tmp/tst-rwlock4.XXXXXX" ; |
34 | char data[ps]; |
35 | void *mem; |
36 | int fd; |
37 | pthread_rwlock_t *r; |
38 | pthread_rwlockattr_t a; |
39 | pid_t pid; |
40 | char *p; |
41 | int err; |
42 | int s; |
43 | |
44 | fd = mkstemp (template: tmpfname); |
45 | if (fd == -1) |
46 | { |
47 | printf (format: "cannot open temporary file: %m\n" ); |
48 | return 1; |
49 | } |
50 | |
51 | /* Make sure it is always removed. */ |
52 | unlink (name: tmpfname); |
53 | |
54 | /* Create one page of data. */ |
55 | memset (data, '\0', ps); |
56 | |
57 | /* Write the data to the file. */ |
58 | if (write (fd, data, ps) != (ssize_t) ps) |
59 | { |
60 | puts (s: "short write" ); |
61 | return 1; |
62 | } |
63 | |
64 | mem = mmap (NULL, len: ps, PROT_READ | PROT_WRITE, MAP_SHARED, fd: fd, offset: 0); |
65 | if (mem == MAP_FAILED) |
66 | { |
67 | printf (format: "mmap failed: %m\n" ); |
68 | return 1; |
69 | } |
70 | |
71 | r = (pthread_rwlock_t *) (((uintptr_t) mem + __alignof (pthread_rwlock_t)) |
72 | & ~(__alignof (pthread_rwlock_t) - 1)); |
73 | p = (char *) (r + 1); |
74 | |
75 | if (pthread_rwlockattr_init (attr: &a) != 0) |
76 | { |
77 | puts (s: "rwlockattr_init failed" ); |
78 | return 1; |
79 | } |
80 | |
81 | if (pthread_rwlockattr_getpshared (attr: &a, pshared: &s) != 0) |
82 | { |
83 | puts (s: "1st rwlockattr_getpshared failed" ); |
84 | return 1; |
85 | } |
86 | |
87 | if (s != PTHREAD_PROCESS_PRIVATE) |
88 | { |
89 | puts (s: "default pshared value wrong" ); |
90 | return 1; |
91 | } |
92 | |
93 | if (pthread_rwlockattr_setpshared (attr: &a, PTHREAD_PROCESS_SHARED) != 0) |
94 | { |
95 | puts (s: "rwlockattr_setpshared failed" ); |
96 | return 1; |
97 | } |
98 | |
99 | if (pthread_rwlockattr_getpshared (attr: &a, pshared: &s) != 0) |
100 | { |
101 | puts (s: "2nd rwlockattr_getpshared failed" ); |
102 | return 1; |
103 | } |
104 | |
105 | if (s != PTHREAD_PROCESS_SHARED) |
106 | { |
107 | puts (s: "pshared value after setpshared call wrong" ); |
108 | return 1; |
109 | } |
110 | |
111 | if (pthread_rwlock_init (rwlock: r, attr: &a) != 0) |
112 | { |
113 | puts (s: "rwlock_init failed" ); |
114 | return 1; |
115 | } |
116 | |
117 | if (pthread_rwlock_rdlock (rwlock: r) != 0) |
118 | { |
119 | puts (s: "rwlock_rdlock failed" ); |
120 | return 1; |
121 | } |
122 | |
123 | if (pthread_rwlockattr_destroy (attr: &a) != 0) |
124 | { |
125 | puts (s: "rwlockattr_destroy failed" ); |
126 | return 1; |
127 | } |
128 | |
129 | err = pthread_rwlock_trywrlock (rwlock: r); |
130 | if (err == 0) |
131 | { |
132 | puts (s: "rwlock_trywrlock succeeded" ); |
133 | return 1; |
134 | } |
135 | else if (err != EBUSY) |
136 | { |
137 | puts (s: "rwlock_trywrlock didn't return EBUSY" ); |
138 | return 1; |
139 | } |
140 | |
141 | *p = 0; |
142 | |
143 | puts (s: "going to fork now" ); |
144 | pid = fork (); |
145 | if (pid == -1) |
146 | { |
147 | puts (s: "fork failed" ); |
148 | return 1; |
149 | } |
150 | else if (pid == 0) |
151 | { |
152 | /* Play some lock ping-pong. It's our turn to unlock first. */ |
153 | if ((*p)++ != 0) |
154 | { |
155 | puts (s: "child: *p != 0" ); |
156 | return 1; |
157 | } |
158 | |
159 | if (pthread_rwlock_unlock (rwlock: r) != 0) |
160 | { |
161 | puts (s: "child: 1st rwlock_unlock failed" ); |
162 | return 1; |
163 | } |
164 | |
165 | puts (s: "child done" ); |
166 | } |
167 | else |
168 | { |
169 | if (pthread_rwlock_wrlock (rwlock: r) != 0) |
170 | { |
171 | puts (s: "parent: rwlock_wrlock failed" ); |
172 | return 1; |
173 | } |
174 | |
175 | if (*p != 1) |
176 | { |
177 | puts (s: "*p != 1" ); |
178 | return 1; |
179 | } |
180 | |
181 | puts (s: "parent done" ); |
182 | } |
183 | |
184 | return 0; |
185 | } |
186 | |
187 | #define TEST_FUNCTION do_test () |
188 | #include "../test-skeleton.c" |
189 | |