1 /* Copyright Joyent, Inc. and other Node contributors. All rights reserved.
2 *
3 * Permission is hereby granted, free of charge, to any person obtaining a copy
4 * of this software and associated documentation files (the "Software"), to
5 * deal in the Software without restriction, including without limitation the
6 * rights to use, copy, modify, merge, publish, distribute, sublicense, and/or
7 * sell copies of the Software, and to permit persons to whom the Software is
8 * furnished to do so, subject to the following conditions:
9 *
10 * The above copyright notice and this permission notice shall be included in
11 * all copies or substantial portions of the Software.
12 *
13 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
14 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
15 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
16 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
17 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
18 * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
19 * IN THE SOFTWARE.
20 */
21
22
23 /* This test does not pretend to be cross-platform. */
24 #ifndef _WIN32
25
26 #include "uv.h"
27 #include "task.h"
28
29 #include <errno.h>
30 #include <signal.h>
31 #include <stdarg.h>
32 #include <stdio.h>
33 #include <stdlib.h>
34 #include <string.h>
35 #include <unistd.h>
36
37 /* The value of NUM_SIGNAL_HANDLING_THREADS is not arbitrary; it needs to be a
38 * multiple of three for reasons that will become clear when you scroll down.
39 * We're basically creating three different thread groups. The total needs
40 * to be divisible by three in order for the numbers in the final check to
41 * match up.
42 */
43 #define NUM_SIGNAL_HANDLING_THREADS 24
44 #define NUM_LOOP_CREATING_THREADS 10
45
46 enum signal_action {
47 ONLY_SIGUSR1,
48 ONLY_SIGUSR2,
49 SIGUSR1_AND_SIGUSR2
50 };
51
52 static uv_sem_t sem;
53 static uv_mutex_t lock;
54 static int stop = 0;
55
56 static int signal1_cb_counter = 0;
57 static int signal2_cb_counter = 0;
58 static int loop_creation_counter = 0;
59
60
increment_counter(int * counter)61 static void increment_counter(int* counter) {
62 uv_mutex_lock(&lock);
63 ++(*counter);
64 uv_mutex_unlock(&lock);
65 }
66
67
signal1_cb(uv_signal_t * handle,int signum)68 static void signal1_cb(uv_signal_t* handle, int signum) {
69 ASSERT_EQ(signum, SIGUSR1);
70 increment_counter(&signal1_cb_counter);
71 uv_signal_stop(handle);
72 }
73
74
signal2_cb(uv_signal_t * handle,int signum)75 static void signal2_cb(uv_signal_t* handle, int signum) {
76 ASSERT_EQ(signum, SIGUSR2);
77 increment_counter(&signal2_cb_counter);
78 uv_signal_stop(handle);
79 }
80
81
signal_handling_worker(void * context)82 static void signal_handling_worker(void* context) {
83 enum signal_action action;
84 uv_signal_t signal1a;
85 uv_signal_t signal1b;
86 uv_signal_t signal2;
87 uv_loop_t loop;
88 int r;
89
90 action = (enum signal_action) (uintptr_t) context;
91
92 ASSERT_OK(uv_loop_init(&loop));
93
94 /* Setup the signal watchers and start them. */
95 if (action == ONLY_SIGUSR1 || action == SIGUSR1_AND_SIGUSR2) {
96 r = uv_signal_init(&loop, &signal1a);
97 ASSERT_OK(r);
98 r = uv_signal_start(&signal1a, signal1_cb, SIGUSR1);
99 ASSERT_OK(r);
100 r = uv_signal_init(&loop, &signal1b);
101 ASSERT_OK(r);
102 r = uv_signal_start(&signal1b, signal1_cb, SIGUSR1);
103 ASSERT_OK(r);
104 }
105
106 if (action == ONLY_SIGUSR2 || action == SIGUSR1_AND_SIGUSR2) {
107 r = uv_signal_init(&loop, &signal2);
108 ASSERT_OK(r);
109 r = uv_signal_start(&signal2, signal2_cb, SIGUSR2);
110 ASSERT_OK(r);
111 }
112
113 /* Signal watchers are now set up. */
114 uv_sem_post(&sem);
115
116 /* Wait for all signals. The signal callbacks stop the watcher, so uv_run
117 * will return when all signal watchers caught a signal.
118 */
119 r = uv_run(&loop, UV_RUN_DEFAULT);
120 ASSERT_OK(r);
121
122 /* Restart the signal watchers. */
123 if (action == ONLY_SIGUSR1 || action == SIGUSR1_AND_SIGUSR2) {
124 r = uv_signal_start(&signal1a, signal1_cb, SIGUSR1);
125 ASSERT_OK(r);
126 r = uv_signal_start(&signal1b, signal1_cb, SIGUSR1);
127 ASSERT_OK(r);
128 }
129
130 if (action == ONLY_SIGUSR2 || action == SIGUSR1_AND_SIGUSR2) {
131 r = uv_signal_start(&signal2, signal2_cb, SIGUSR2);
132 ASSERT_OK(r);
133 }
134
135 /* Wait for signals once more. */
136 uv_sem_post(&sem);
137
138 r = uv_run(&loop, UV_RUN_DEFAULT);
139 ASSERT_OK(r);
140
141 /* Close the watchers. */
142 if (action == ONLY_SIGUSR1 || action == SIGUSR1_AND_SIGUSR2) {
143 uv_close((uv_handle_t*) &signal1a, NULL);
144 uv_close((uv_handle_t*) &signal1b, NULL);
145 }
146
147 if (action == ONLY_SIGUSR2 || action == SIGUSR1_AND_SIGUSR2) {
148 uv_close((uv_handle_t*) &signal2, NULL);
149 }
150
151 /* Wait for the signal watchers to close. */
152 r = uv_run(&loop, UV_RUN_DEFAULT);
153 ASSERT_OK(r);
154
155 uv_loop_close(&loop);
156 }
157
158
signal_unexpected_cb(uv_signal_t * handle,int signum)159 static void signal_unexpected_cb(uv_signal_t* handle, int signum) {
160 ASSERT(0 && "signal_unexpected_cb should never be called");
161 }
162
163
loop_creating_worker(void * context)164 static void loop_creating_worker(void* context) {
165 int done;
166
167 (void) context;
168
169 do {
170 uv_loop_t *loop;
171 uv_signal_t signal;
172 int r;
173
174 loop = malloc(sizeof(*loop));
175 ASSERT_NOT_NULL(loop);
176 ASSERT_OK(uv_loop_init(loop));
177
178 r = uv_signal_init(loop, &signal);
179 ASSERT_OK(r);
180
181 r = uv_signal_start(&signal, signal_unexpected_cb, SIGTERM);
182 ASSERT_OK(r);
183
184 uv_close((uv_handle_t*) &signal, NULL);
185
186 r = uv_run(loop, UV_RUN_DEFAULT);
187 ASSERT_OK(r);
188
189 uv_loop_close(loop);
190 free(loop);
191
192 increment_counter(&loop_creation_counter);
193
194 uv_mutex_lock(&lock);
195 done = stop;
196 uv_mutex_unlock(&lock);
197 } while (!done);
198 }
199
200
TEST_IMPL(signal_multiple_loops)201 TEST_IMPL(signal_multiple_loops) {
202 #if defined(__CYGWIN__) || defined(__MSYS__)
203 /* FIXME: This test needs more investigation. Somehow the `read` in
204 uv__signal_lock fails spuriously with EACCES or even EAGAIN even
205 though it is supposed to be blocking. Also the test hangs during
206 thread setup occasionally. */
207 RETURN_SKIP("FIXME: This test needs more investigation on Cygwin");
208 #endif
209 /* TODO(gengjiawen): Fix test on QEMU. */
210 #if defined(__QEMU__)
211 /* See https://github.com/libuv/libuv/issues/2859 */
212 RETURN_SKIP("QEMU's signal emulation code is notoriously tricky");
213 #endif
214 #if defined(__ASAN__) || defined(__MSAN__)
215 /* See https://github.com/libuv/libuv/issues/3956 */
216 RETURN_SKIP("Test is too slow to run under ASan or MSan");
217 #endif
218 #if defined(__TSAN__)
219 /* ThreadSanitizer complains - likely legitimately - about data races
220 * in uv__signal_compare() in src/unix/signal.c but that's pre-existing.
221 */
222 RETURN_SKIP("Fix test under ThreadSanitizer");
223 #endif
224 uv_thread_t loop_creating_threads[NUM_LOOP_CREATING_THREADS];
225 uv_thread_t signal_handling_threads[NUM_SIGNAL_HANDLING_THREADS];
226 enum signal_action action;
227 sigset_t sigset;
228 int i;
229 int r;
230
231 r = uv_sem_init(&sem, 0);
232 ASSERT_OK(r);
233
234 r = uv_mutex_init(&lock);
235 ASSERT_OK(r);
236
237 /* Create a couple of threads that create a destroy loops continuously. */
238 for (i = 0; i < NUM_LOOP_CREATING_THREADS; i++) {
239 r = uv_thread_create(&loop_creating_threads[i],
240 loop_creating_worker,
241 NULL);
242 ASSERT_OK(r);
243 }
244
245 /* Create a couple of threads that actually handle signals. */
246 for (i = 0; i < NUM_SIGNAL_HANDLING_THREADS; i++) {
247 switch (i % 3) {
248 case 0: action = ONLY_SIGUSR1; break;
249 case 1: action = ONLY_SIGUSR2; break;
250 case 2: action = SIGUSR1_AND_SIGUSR2; break;
251 }
252
253 r = uv_thread_create(&signal_handling_threads[i],
254 signal_handling_worker,
255 (void*) (uintptr_t) action);
256 ASSERT_OK(r);
257 }
258
259 /* Wait until all threads have started and set up their signal watchers. */
260 for (i = 0; i < NUM_SIGNAL_HANDLING_THREADS; i++)
261 uv_sem_wait(&sem);
262
263 r = kill(getpid(), SIGUSR1);
264 ASSERT_OK(r);
265 r = kill(getpid(), SIGUSR2);
266 ASSERT_OK(r);
267
268 /* Wait for all threads to handle these signals. */
269 for (i = 0; i < NUM_SIGNAL_HANDLING_THREADS; i++)
270 uv_sem_wait(&sem);
271
272 /* Block all signals to this thread, so we are sure that from here the signal
273 * handler runs in another thread. This is more likely to catch thread and
274 * signal safety issues if there are any.
275 */
276 sigfillset(&sigset);
277 pthread_sigmask(SIG_SETMASK, &sigset, NULL);
278
279 r = kill(getpid(), SIGUSR1);
280 ASSERT_OK(r);
281 r = kill(getpid(), SIGUSR2);
282 ASSERT_OK(r);
283
284 /* Wait for all signal handling threads to exit. */
285 for (i = 0; i < NUM_SIGNAL_HANDLING_THREADS; i++) {
286 r = uv_thread_join(&signal_handling_threads[i]);
287 ASSERT_OK(r);
288 }
289
290 /* Tell all loop creating threads to stop. */
291 uv_mutex_lock(&lock);
292 stop = 1;
293 uv_mutex_unlock(&lock);
294
295 /* Wait for all loop creating threads to exit. */
296 for (i = 0; i < NUM_LOOP_CREATING_THREADS; i++) {
297 r = uv_thread_join(&loop_creating_threads[i]);
298 ASSERT_OK(r);
299 }
300
301 uv_sem_destroy(&sem);
302 printf("signal1_cb calls: %d\n", signal1_cb_counter);
303 printf("signal2_cb calls: %d\n", signal2_cb_counter);
304 printf("loops created and destroyed: %d\n", loop_creation_counter);
305
306 /* The division by three reflects the fact that we spawn three different
307 * thread groups of (NUM_SIGNAL_HANDLING_THREADS / 3) threads each.
308 */
309 ASSERT_EQ(signal1_cb_counter, 8 * (NUM_SIGNAL_HANDLING_THREADS / 3));
310 ASSERT_EQ(signal2_cb_counter, 4 * (NUM_SIGNAL_HANDLING_THREADS / 3));
311
312 /* We don't know exactly how much loops will be created and destroyed, but at
313 * least there should be 1 for every loop creating thread.
314 */
315 ASSERT_GE(loop_creation_counter, NUM_LOOP_CREATING_THREADS);
316
317 MAKE_VALGRIND_HAPPY(uv_default_loop());
318 return 0;
319 }
320
321 #else
322
323 typedef int file_has_no_tests; /* ISO C forbids an empty translation unit. */
324
325 #endif /* !_WIN32 */
326
