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-rw-r--r--gnulib-tests/test-pthread-mutex.c365
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diff --git a/gnulib-tests/test-pthread-mutex.c b/gnulib-tests/test-pthread-mutex.c
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+/* Test of locking in multithreaded situations.
+ Copyright (C) 2005, 2008-2022 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/>. */
+
+/* Written by Bruno Haible <bruno@clisp.org>, 2005. */
+
+#include <config.h>
+
+#if USE_ISOC_THREADS || USE_POSIX_THREADS || USE_ISOC_AND_POSIX_THREADS || USE_WINDOWS_THREADS
+
+/* Whether to enable locking.
+ Uncomment this to get a test program without locking, to verify that
+ it crashes. */
+#define ENABLE_LOCKING 1
+
+/* Which tests to perform.
+ Uncomment some of these, to verify that all tests crash if no locking
+ is enabled. */
+#define DO_TEST_LOCK 1
+#define DO_TEST_RECURSIVE_LOCK 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
+
+/* Number of simultaneous threads. */
+#define THREAD_COUNT 10
+
+/* Number of operations performed in each thread.
+ This is quite high, because with a smaller count, say 5000, we often get
+ an "OK" result even without ENABLE_LOCKING (on Linux/x86). */
+#define REPEAT_COUNT 50000
+
+#include <pthread.h>
+#include <stdint.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+
+#if EXPLICIT_YIELD
+# include <sched.h>
+#endif
+
+#if HAVE_DECL_ALARM
+# include <signal.h>
+# include <unistd.h>
+#endif
+
+#include "macros.h"
+#include "atomic-int-posix.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
+
+/* Returns a reference to the current thread as a pointer, for debugging. */
+#if defined __MVS__
+ /* On IBM z/OS, pthread_t is a struct with an 8-byte '__' field.
+ The first three bytes of this field appear to uniquely identify a
+ pthread_t, though not necessarily representing a pointer. */
+# define pthread_self_pointer() (*((void **) pthread_self ().__))
+#else
+# define pthread_self_pointer() ((void *) (uintptr_t) pthread_self ())
+#endif
+
+#define ACCOUNT_COUNT 4
+
+static int account[ACCOUNT_COUNT];
+
+static int
+random_account (void)
+{
+ return ((unsigned int) rand () >> 3) % ACCOUNT_COUNT;
+}
+
+static void
+check_accounts (void)
+{
+ int i, sum;
+
+ sum = 0;
+ for (i = 0; i < ACCOUNT_COUNT; i++)
+ sum += account[i];
+ if (sum != ACCOUNT_COUNT * 1000)
+ abort ();
+}
+
+
+/* ------------------- Test normal (non-recursive) locks ------------------- */
+
+/* Test normal locks by having several bank accounts and several threads
+ which shuffle around money between the accounts and another thread
+ checking that all the money is still there. */
+
+static pthread_mutex_t my_lock;
+
+static void *
+lock_mutator_thread (void *arg)
+{
+ int repeat;
+
+ for (repeat = REPEAT_COUNT; repeat > 0; repeat--)
+ {
+ int i1, i2, value;
+
+ dbgprintf ("Mutator %p before lock\n", pthread_self_pointer ());
+ ASSERT (pthread_mutex_lock (&my_lock) == 0);
+ dbgprintf ("Mutator %p after lock\n", pthread_self_pointer ());
+
+ i1 = random_account ();
+ i2 = random_account ();
+ value = ((unsigned int) rand () >> 3) % 10;
+ account[i1] += value;
+ account[i2] -= value;
+
+ dbgprintf ("Mutator %p before unlock\n", pthread_self_pointer ());
+ ASSERT (pthread_mutex_unlock (&my_lock) == 0);
+ dbgprintf ("Mutator %p after unlock\n", pthread_self_pointer ());
+
+ dbgprintf ("Mutator %p before check lock\n", pthread_self_pointer ());
+ ASSERT (pthread_mutex_lock (&my_lock) == 0);
+ check_accounts ();
+ ASSERT (pthread_mutex_unlock (&my_lock) == 0);
+ dbgprintf ("Mutator %p after check unlock\n", pthread_self_pointer ());
+
+ yield ();
+ }
+
+ dbgprintf ("Mutator %p dying.\n", pthread_self_pointer ());
+ return NULL;
+}
+
+static struct atomic_int lock_checker_done;
+
+static void *
+lock_checker_thread (void *arg)
+{
+ while (get_atomic_int_value (&lock_checker_done) == 0)
+ {
+ dbgprintf ("Checker %p before check lock\n", pthread_self_pointer ());
+ ASSERT (pthread_mutex_lock (&my_lock) == 0);
+ check_accounts ();
+ ASSERT (pthread_mutex_unlock (&my_lock) == 0);
+ dbgprintf ("Checker %p after check unlock\n", pthread_self_pointer ());
+
+ yield ();
+ }
+
+ dbgprintf ("Checker %p dying.\n", pthread_self_pointer ());
+ return NULL;
+}
+
+static void
+test_pthread_mutex_normal (void)
+{
+ int i;
+ pthread_t checkerthread;
+ pthread_t threads[THREAD_COUNT];
+
+ /* Initialization. */
+ for (i = 0; i < ACCOUNT_COUNT; i++)
+ account[i] = 1000;
+ init_atomic_int (&lock_checker_done);
+ set_atomic_int_value (&lock_checker_done, 0);
+
+ /* Spawn the threads. */
+ ASSERT (pthread_create (&checkerthread, NULL, lock_checker_thread, NULL)
+ == 0);
+ for (i = 0; i < THREAD_COUNT; i++)
+ ASSERT (pthread_create (&threads[i], NULL, lock_mutator_thread, NULL) == 0);
+
+ /* Wait for the threads to terminate. */
+ for (i = 0; i < THREAD_COUNT; i++)
+ ASSERT (pthread_join (threads[i], NULL) == 0);
+ set_atomic_int_value (&lock_checker_done, 1);
+ ASSERT (pthread_join (checkerthread, NULL) == 0);
+ check_accounts ();
+}
+
+
+/* -------------------------- Test recursive locks -------------------------- */
+
+/* Test recursive locks by having several bank accounts and several threads
+ which shuffle around money between the accounts (recursively) and another
+ thread checking that all the money is still there. */
+
+static pthread_mutex_t my_reclock;
+
+static void
+recshuffle (void)
+{
+ int i1, i2, value;
+
+ dbgprintf ("Mutator %p before lock\n", pthread_self_pointer ());
+ ASSERT (pthread_mutex_lock (&my_reclock) == 0);
+ dbgprintf ("Mutator %p after lock\n", pthread_self_pointer ());
+
+ i1 = random_account ();
+ i2 = random_account ();
+ value = ((unsigned int) rand () >> 3) % 10;
+ account[i1] += value;
+ account[i2] -= value;
+
+ /* Recursive with probability 0.5. */
+ if (((unsigned int) rand () >> 3) % 2)
+ recshuffle ();
+
+ dbgprintf ("Mutator %p before unlock\n", pthread_self_pointer ());
+ ASSERT (pthread_mutex_unlock (&my_reclock) == 0);
+ dbgprintf ("Mutator %p after unlock\n", pthread_self_pointer ());
+}
+
+static void *
+reclock_mutator_thread (void *arg)
+{
+ int repeat;
+
+ for (repeat = REPEAT_COUNT; repeat > 0; repeat--)
+ {
+ recshuffle ();
+
+ dbgprintf ("Mutator %p before check lock\n", pthread_self_pointer ());
+ ASSERT (pthread_mutex_lock (&my_reclock) == 0);
+ check_accounts ();
+ ASSERT (pthread_mutex_unlock (&my_reclock) == 0);
+ dbgprintf ("Mutator %p after check unlock\n", pthread_self_pointer ());
+
+ yield ();
+ }
+
+ dbgprintf ("Mutator %p dying.\n", pthread_self_pointer ());
+ return NULL;
+}
+
+static struct atomic_int reclock_checker_done;
+
+static void *
+reclock_checker_thread (void *arg)
+{
+ while (get_atomic_int_value (&reclock_checker_done) == 0)
+ {
+ dbgprintf ("Checker %p before check lock\n", pthread_self_pointer ());
+ ASSERT (pthread_mutex_lock (&my_reclock) == 0);
+ check_accounts ();
+ ASSERT (pthread_mutex_unlock (&my_reclock) == 0);
+ dbgprintf ("Checker %p after check unlock\n", pthread_self_pointer ());
+
+ yield ();
+ }
+
+ dbgprintf ("Checker %p dying.\n", pthread_self_pointer ());
+ return NULL;
+}
+
+static void
+test_pthread_mutex_recursive (void)
+{
+ int i;
+ pthread_t checkerthread;
+ pthread_t threads[THREAD_COUNT];
+
+ /* Initialization. */
+ for (i = 0; i < ACCOUNT_COUNT; i++)
+ account[i] = 1000;
+ init_atomic_int (&reclock_checker_done);
+ set_atomic_int_value (&reclock_checker_done, 0);
+
+ /* Spawn the threads. */
+ ASSERT (pthread_create (&checkerthread, NULL, reclock_checker_thread, NULL)
+ == 0);
+ for (i = 0; i < THREAD_COUNT; i++)
+ ASSERT (pthread_create (&threads[i], NULL, reclock_mutator_thread, NULL)
+ == 0);
+
+ /* Wait for the threads to terminate. */
+ for (i = 0; i < THREAD_COUNT; i++)
+ ASSERT (pthread_join (threads[i], NULL) == 0);
+ set_atomic_int_value (&reclock_checker_done, 1);
+ ASSERT (pthread_join (checkerthread, NULL) == 0);
+ check_accounts ();
+}
+
+
+/* -------------------------------------------------------------------------- */
+
+int
+main ()
+{
+#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
+
+ {
+ pthread_mutexattr_t attr;
+
+ ASSERT (pthread_mutexattr_init (&attr) == 0);
+ ASSERT (pthread_mutexattr_settype (&attr, PTHREAD_MUTEX_NORMAL) == 0);
+ ASSERT (pthread_mutex_init (&my_lock, &attr) == 0);
+ ASSERT (pthread_mutexattr_destroy (&attr) == 0);
+ }
+
+ {
+ pthread_mutexattr_t attr;
+
+ ASSERT (pthread_mutexattr_init (&attr) == 0);
+ ASSERT (pthread_mutexattr_settype (&attr, PTHREAD_MUTEX_RECURSIVE) == 0);
+ ASSERT (pthread_mutex_init (&my_reclock, &attr) == 0);
+ ASSERT (pthread_mutexattr_destroy (&attr) == 0);
+ }
+
+#if DO_TEST_LOCK
+ printf ("Starting test_pthread_mutex_normal ..."); fflush (stdout);
+ test_pthread_mutex_normal ();
+ printf (" OK\n"); fflush (stdout);
+#endif
+#if DO_TEST_RECURSIVE_LOCK
+ printf ("Starting test_pthread_mutex_recursive ..."); fflush (stdout);
+ test_pthread_mutex_recursive ();
+ printf (" OK\n"); fflush (stdout);
+#endif
+
+ return 0;
+}
+
+#else
+
+/* No multithreading available. */
+
+#include <stdio.h>
+
+int
+main ()
+{
+ fputs ("Skipping test: multithreading not enabled\n", stderr);
+ return 77;
+}
+
+#endif
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