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
46enum signal_action {
47  ONLY_SIGUSR1,
48  ONLY_SIGUSR2,
49  SIGUSR1_AND_SIGUSR2
50};
51
52static uv_sem_t sem;
53static uv_mutex_t lock;
54static int stop = 0;
55
56static int signal1_cb_counter = 0;
57static int signal2_cb_counter = 0;
58static int loop_creation_counter = 0;
59
60
61static void increment_counter(int* counter) {
62  uv_mutex_lock(&lock);
63  ++(*counter);
64  uv_mutex_unlock(&lock);
65}
66
67
68static 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
75static 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
82static 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
159static void signal_unexpected_cb(uv_signal_t* handle, int signum) {
160  ASSERT(0 && "signal_unexpected_cb should never be called");
161}
162
163
164static 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
201TEST_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
323typedef int file_has_no_tests; /* ISO C forbids an empty translation unit. */
324
325#endif /* !_WIN32 */
326