nptl/tst-pthread-attr-sigmask.c

   1 /* Tests for pthread_attr_setsigmask_np, pthread_attr_getsigmask_np.
   2    Copyright (C) 2020-2024 Free Software Foundation, Inc.
   3    This file is part of the GNU C Library.
   4
   5    The GNU C Library is free software; you can redistribute it and/or
   6    modify it under the terms of the GNU Lesser General Public
   7    License as published by the Free Software Foundation; either
   8    version 2.1 of the License, or (at your option) any later version.
   9
  10    The GNU C Library is distributed in the hope that it will be useful,
  11    but WITHOUT ANY WARRANTY; without even the implied warranty of
  12    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  13    Lesser General Public License for more details.
  14
  15    You should have received a copy of the GNU Lesser General Public
  16    License along with the GNU C Library; if not, see
  17    <https://www.gnu.org/licenses/>.  */
  18
  19 /* This thread uses different masked status for SIGUSR1, SIGUSR2,
  20    SIGHUP to determine if signal masks are applied to new threads as
  21    expected.  */
  22
  23 #include <signal.h>
  24 #include <stdbool.h>
  25 #include <stddef.h>
  26 #include <stdio.h>
  27 #include <support/check.h>
  28 #include <support/xsignal.h>
  29 #include <support/xthread.h>
  30 #include <threads.h>
  31
  32 typedef bool signals[_NSIG];
  33
  34 static const char *
  35 masked_or_unmasked (bool masked)
  36 {
  37   if (masked)
  38     return "masked";
  39   else
  40     return "unmasked";
  41 }
  42
  43 /* Report an error if ACTUAL_MASK does not match EXPECTED_MASK.
  44    CONTEXT is used in error messages.  */
  45 static void
  46 check_sigmask (const char *context, signals expected_mask,
  47                const sigset_t *actual_mask)
  48 {
  49   for (int sig = 1; sig < _NSIG; ++sig)
  50     if (sigismember (actual_mask, sig) != expected_mask[sig])
  51       {
  52         support_record_failure ();
  53         printf ("error: %s: signal %d should be %s, but is %s\n",
  54                 context, sig,
  55                 masked_or_unmasked (sigismember (actual_mask, sig)),
  56                 masked_or_unmasked (expected_mask[sig]));
  57       }
  58 }
  59
  60 /* Report an error if the current thread signal mask does not match
  61    EXPECTED_MASK.  CONTEXT is used in error messages.  */
  62 static void
  63 check_current_sigmask (const char *context, signals expected_mask)
  64 {
  65   sigset_t actual_mask;
  66   xpthread_sigmask (SIG_SETMASK, NULL, &actual_mask);
  67   check_sigmask (context, expected_mask, &actual_mask);
  68 }
  69
  70 /* Thread start routine which checks the current thread signal mask
  71    against CLOSURE.  */
  72 static void *
  73 check_sigmask_thread_function (void *closure)
  74 {
  75   check_current_sigmask ("on thread", closure);
  76   return NULL;
  77 }
  78
  79 /* Same for C11 threads.  */
  80 static int
  81 check_sigmask_thread_function_c11 (void *closure)
  82 {
  83   check_current_sigmask ("on C11 thread", closure);
  84   return 0;
  85 }
  86
  87 /* Launch a POSIX thread with ATTR (which can be NULL) and check that
  88    it has the expected signal mask.  */
  89 static void
  90 check_posix_thread (pthread_attr_t *attr, signals expected_mask)
  91 {
  92   xpthread_join (xpthread_create (attr, check_sigmask_thread_function,
  93                                   expected_mask));
  94 }
  95
  96 /* Launch a C11 thread and check that it has the expected signal
  97    mask.  */
  98 static void
  99 check_c11_thread (signals expected_mask)
 100 {
 101   thrd_t thr;
 102   TEST_VERIFY_EXIT (thrd_create (&thr, check_sigmask_thread_function_c11,
 103                                  expected_mask) == thrd_success);
 104   TEST_VERIFY_EXIT (thrd_join (thr, NULL) == thrd_success);
 105 }
 106
 107 static int
 108 do_test (void)
 109 {
 110   check_current_sigmask ("initial mask", (signals) { false, });
 111   check_posix_thread (NULL, (signals) { false, });
 112   check_c11_thread ((signals) { false, });
 113
 114   sigset_t set;
 115   sigemptyset (&set);
 116   sigaddset (&set, SIGUSR1);
 117   xpthread_sigmask (SIG_SETMASK, &set, NULL);
 118   check_current_sigmask ("SIGUSR1 masked", (signals) { [SIGUSR1] = true, });
 119   /* The signal mask is inherited by the new thread.  */
 120   check_posix_thread (NULL, (signals) { [SIGUSR1] = true, });
 121   check_c11_thread ((signals) { [SIGUSR1] = true, });
 122
 123   pthread_attr_t attr;
 124   xpthread_attr_init (&attr);
 125   TEST_COMPARE (pthread_attr_getsigmask_np (&attr, &set),
 126                 PTHREAD_ATTR_NO_SIGMASK_NP);
 127   /* By default, the signal mask is inherited (even with an explicit
 128      thread attribute).  */
 129   check_posix_thread (&attr, (signals) { [SIGUSR1] = true, });
 130
 131   /* Check that pthread_attr_getsigmask_np can obtain the signal
 132      mask.  */
 133   sigemptyset (&set);
 134   sigaddset (&set, SIGUSR2);
 135   TEST_COMPARE (pthread_attr_setsigmask_np (&attr, &set), 0);
 136   sigemptyset (&set);
 137   TEST_COMPARE (pthread_attr_getsigmask_np (&attr, &set), 0);
 138   check_sigmask ("pthread_attr_getsigmask_np", (signals) { [SIGUSR2] = true, },
 139                  &set);
 140
 141   /* Check that a thread is launched with the configured signal
 142      mask.  */
 143   check_current_sigmask ("SIGUSR1 masked", (signals) { [SIGUSR1] = true, });
 144   check_posix_thread (&attr, (signals) { [SIGUSR2] = true, });
 145   check_current_sigmask ("SIGUSR1 masked", (signals) { [SIGUSR1] = true, });
 146
 147   /* But C11 threads remain at inheritance.  */
 148   check_c11_thread ((signals) { [SIGUSR1] = true, });
 149
 150   /* Check that filling the original signal set does not affect thread
 151      creation.  */
 152   sigfillset (&set);
 153   check_posix_thread (&attr, (signals) { [SIGUSR2] = true, });
 154
 155   /* Check that clearing the signal in the attribute restores
 156      inheritance.  */
 157   TEST_COMPARE (pthread_attr_setsigmask_np (&attr, NULL), 0);
 158   TEST_COMPARE (pthread_attr_getsigmask_np (&attr, &set),
 159                 PTHREAD_ATTR_NO_SIGMASK_NP);
 160   check_posix_thread (&attr, (signals) { [SIGUSR1] = true, });
 161
 162   /* Mask SIGHUP via the default thread attribute.  */
 163   sigemptyset (&set);
 164   sigaddset (&set, SIGHUP);
 165   TEST_COMPARE (pthread_attr_setsigmask_np (&attr, &set), 0);
 166   TEST_COMPARE (pthread_setattr_default_np (&attr), 0);
 167
 168   /* Check that the mask was applied to the default attribute.  */
 169   xpthread_attr_destroy (&attr);
 170   TEST_COMPARE (pthread_getattr_default_np (&attr), 0);
 171   sigaddset (&set, SIGHUP);
 172   TEST_COMPARE (pthread_attr_getsigmask_np (&attr, &set), 0);
 173   check_sigmask ("default attribute", (signals) { [SIGHUP] = true, }, &set);
 174   xpthread_attr_destroy (&attr);
 175
 176   /* Check that the default attribute is applied.  */
 177   check_posix_thread (NULL, (signals) { [SIGHUP] = true, });
 178   check_c11_thread ((signals) { [SIGHUP] = true, });
 179
 180   /* An explicit attribute with no signal mask triggers inheritance
 181      even if the default has been changed.  */
 182   xpthread_attr_init (&attr);
 183   check_posix_thread (&attr, (signals) { [SIGUSR1] = true, });
 184
 185   /* Explicitly setting the signal mask affects the new thread even
 186      with a default attribute.  */
 187   sigemptyset (&set);
 188   sigaddset (&set, SIGUSR2);
 189   TEST_COMPARE (pthread_attr_setsigmask_np (&attr, &set), 0);
 190   check_posix_thread (&attr, (signals) { [SIGUSR2] = true, });
 191
 192   /* Resetting the default attribute brings back the old inheritance
 193      behavior.  */
 194   xpthread_attr_destroy (&attr);
 195   xpthread_attr_init (&attr);
 196   TEST_COMPARE (pthread_setattr_default_np (&attr), 0);
 197   xpthread_attr_destroy (&attr);
 198   check_posix_thread (NULL, (signals) { [SIGUSR1] = true, });
 199   check_c11_thread ((signals) { [SIGUSR1] = true, });
 200
 201   return 0;
 202 }
 203
 204 #include <support/test-driver.c>