1 files changed, 301 insertions, 0 deletions
diff --git a/tests/test-pthread-cond.c b/tests/test-pthread-cond.c
new file mode 100644
index 00000000..3f621fa1
--- /dev/null
+++ b/tests/test-pthread-cond.c
@@ -0,0 +1,301 @@
+/* Test of condition variables in multithreaded situations.
+   Copyright (C) 2008-2024 Free Software Foundation, Inc.
+
+   This program is free software: you can redistribute it and/or modify
+   it under the terms of the GNU General Public License as published by
+   the Free Software Foundation, either version 3 of the License, or
+   (at your option) any later version.
+
+   This program is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+   GNU General Public License for more details.
+
+   You should have received a copy of the GNU General Public License
+   along with this program.  If not, see <https://www.gnu.org/licenses/>.  */
+
+#include <config.h>
+
+#if USE_ISOC_THREADS || USE_POSIX_THREADS || USE_ISOC_AND_POSIX_THREADS || USE_WINDOWS_THREADS
+
+/* Which tests to perform.
+   Uncomment some of these, to verify that all tests crash if no locking
+   is enabled.  */
+#define DO_TEST_COND 1
+#define DO_TEST_TIMEDCOND 1
+
+/* Whether to help the scheduler through explicit sched_yield().
+   Uncomment this to see if the operating system has a fair scheduler.  */
+#define EXPLICIT_YIELD 1
+
+/* Whether to print debugging messages.  */
+#define ENABLE_DEBUGGING 0
+
+#include <pthread.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <sys/time.h>
+
+#if EXPLICIT_YIELD
+# include <sched.h>
+#endif
+
+#if HAVE_DECL_ALARM
+# include <signal.h>
+# include <unistd.h>
+#endif
+
+#include "virtualbox.h"
+#include "macros.h"
+
+#if ENABLE_DEBUGGING
+# define dbgprintf printf
+#else
+# define dbgprintf if (0) printf
+#endif
+
+#if EXPLICIT_YIELD
+# define yield() sched_yield ()
+#else
+# define yield()
+#endif
+
+
+/*
+ * Condition check
+ */
+
+/* Marked volatile so that different threads see the same value.  This is
+   good enough in practice, although in theory stdatomic.h should be used.  */
+static int volatile cond_value;
+static pthread_cond_t condtest;
+static pthread_mutex_t lockcond;
+
+static void *
+pthread_cond_wait_routine (void *arg)
+{
+  ASSERT (pthread_mutex_lock (&lockcond) == 0);
+  if (cond_value)
+    {
+      /* The main thread already slept, and nevertheless this thread comes
+         too late.  */
+      *(int *)arg = 1;
+    }
+  else
+    {
+      do
+        {
+          ASSERT (pthread_cond_wait (&condtest, &lockcond) == 0);
+        }
+      while (!cond_value);
+    }
+  ASSERT (pthread_mutex_unlock (&lockcond) == 0);
+
+  cond_value = 2;
+
+  return NULL;
+}
+
+static int
+test_pthread_cond_wait ()
+{
+  int skipped = 0;
+  pthread_t thread;
+  int ret;
+
+  cond_value = 0;
+
+  /* Create a separate thread.  */
+  ASSERT (pthread_create (&thread, NULL, pthread_cond_wait_routine, &skipped)
+          == 0);
+
+  /* Sleep for 2 seconds.  */
+  {
+    struct timespec remaining;
+
+    remaining.tv_sec = 2;
+    remaining.tv_nsec = 0;
+
+    do
+      {
+        yield ();
+        ret = nanosleep (&remaining, &remaining);
+        ASSERT (ret >= -1);
+      }
+    while (ret == -1 && (remaining.tv_sec != 0 || remaining.tv_nsec != 0));
+  }
+
+  /* Tell one of the waiting threads (if any) to continue.  */
+  ASSERT (pthread_mutex_lock (&lockcond) == 0);
+  cond_value = 1;
+  ASSERT (pthread_cond_signal (&condtest) == 0);
+  ASSERT (pthread_mutex_unlock (&lockcond) == 0);
+
+  ASSERT (pthread_join (thread, NULL) == 0);
+
+  if (cond_value != 2)
+    abort ();
+
+  return skipped;
+}
+
+
+/*
+ * Timed Condition check
+ */
+
+/* Marked volatile so that different threads see the same value.  This is
+   good enough in practice, although in theory stdatomic.h should be used.  */
+static int volatile cond_timed_out;
+
+/* Stores in *TS the current time plus 1 second.  */
+static void
+get_ts (struct timespec *ts)
+{
+  struct timeval now;
+
+  gettimeofday (&now, NULL);
+
+  ts->tv_sec = now.tv_sec + 1;
+  ts->tv_nsec = now.tv_usec * 1000;
+}
+
+static void *
+pthread_cond_timedwait_routine (void *arg)
+{
+  int ret;
+  struct timespec ts;
+
+  ASSERT (pthread_mutex_lock (&lockcond) == 0);
+  if (cond_value)
+    {
+      /* The main thread already slept, and nevertheless this thread comes
+         too late.  */
+      *(int *)arg = 1;
+    }
+  else
+    {
+      do
+        {
+          get_ts (&ts);
+          ret = pthread_cond_timedwait (&condtest, &lockcond, &ts);
+          if (ret == ETIMEDOUT)
+            cond_timed_out = 1;
+        }
+      while (!cond_value);
+    }
+  ASSERT (pthread_mutex_unlock (&lockcond) == 0);
+
+  return NULL;
+}
+
+static int
+test_pthread_cond_timedwait (void)
+{
+  int skipped = 0;
+  pthread_t thread;
+  int ret;
+
+  cond_value = cond_timed_out = 0;
+
+  /* Create a separate thread.  */
+  ASSERT (pthread_create (&thread, NULL,
+                          pthread_cond_timedwait_routine, &skipped)
+          == 0);
+
+  /* Sleep for 2 seconds.  */
+  {
+    struct timespec remaining;
+
+    remaining.tv_sec = 2;
+    remaining.tv_nsec = 0;
+
+    do
+      {
+        yield ();
+        ret = nanosleep (&remaining, &remaining);
+        ASSERT (ret >= -1);
+      }
+    while (ret == -1 && (remaining.tv_sec != 0 || remaining.tv_nsec != 0));
+  }
+
+  /* Tell one of the waiting threads (if any) to continue.  */
+  ASSERT (pthread_mutex_lock (&lockcond) == 0);
+  cond_value = 1;
+  ASSERT (pthread_cond_signal (&condtest) == 0);
+  ASSERT (pthread_mutex_unlock (&lockcond) == 0);
+
+  ASSERT (pthread_join (thread, NULL) == 0);
+
+  if (!cond_timed_out)
+    abort ();
+
+  return skipped;
+}
+
+
+int
+main ()
+{
+  /* This test occasionally fails on Linux (glibc or musl libc), in a
+     VirtualBox VM with paravirtualization = Default or KVM, with ≥ 2 CPUs.
+     Skip the test in this situation.  */
+  if (is_running_under_virtualbox_kvm () && num_cpus () > 1)
+    {
+      fputs ("Skipping test: avoiding VirtualBox bug with KVM paravirtualization\n",
+             stderr);
+      return 77;
+    }
+
+#if HAVE_DECL_ALARM
+  /* Declare failure if test takes too long, by using default abort
+     caused by SIGALRM.  */
+  int alarm_value = 600;
+  signal (SIGALRM, SIG_DFL);
+  alarm (alarm_value);
+#endif
+
+  ASSERT (pthread_cond_init (&condtest, NULL) == 0);
+
+  {
+    pthread_mutexattr_t attr;
+
+    ASSERT (pthread_mutexattr_init (&attr) == 0);
+    ASSERT (pthread_mutexattr_settype (&attr, PTHREAD_MUTEX_NORMAL) == 0);
+    ASSERT (pthread_mutex_init (&lockcond, &attr) == 0);
+    ASSERT (pthread_mutexattr_destroy (&attr) == 0);
+  }
+
+#if DO_TEST_COND
+  printf ("Starting test_pthread_cond_wait ..."); fflush (stdout);
+  {
+    int skipped = test_pthread_cond_wait ();
+    printf (skipped ? " SKIP\n" : " OK\n"); fflush (stdout);
+  }
+#endif
+#if DO_TEST_TIMEDCOND
+  printf ("Starting test_pthread_cond_timedwait ..."); fflush (stdout);
+  {
+    int skipped = test_pthread_cond_timedwait ();
+    printf (skipped ? " SKIP\n" : " OK\n"); fflush (stdout);
+  }
+#endif
+
+  return test_exit_status;
+}
+
+#else
+
+/* No multithreading available.  */
+
+#include <stdio.h>
+
+int
+main ()
+{
+  fputs ("Skipping test: multithreading not enabled\n", stderr);
+  return 77;
+}
+
+#endif