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-rw-r--r--linuxthreads/Examples/ex11.c152
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diff --git a/linuxthreads/Examples/ex11.c b/linuxthreads/Examples/ex11.c
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+/* Test program for timedout read/write lock functions.
+ Copyright (C) 2000 Free Software Foundation, Inc.
+ Contributed by Ulrich Drepper <drepper@redhat.com>, 2000.
+
+ The GNU C Library is free software; you can redistribute it and/or
+ modify it under the terms of the GNU Library General Public License as
+ published by the Free Software Foundation; either version 2 of the
+ License, or (at your option) any later version.
+
+ The GNU C Library 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
+ Library General Public License for more details.
+
+ You should have received a copy of the GNU Library General Public
+ License along with the GNU C Library; see the file COPYING.LIB. If not,
+ write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
+ Boston, MA 02111-1307, USA. */
+
+#include <errno.h>
+#include <error.h>
+#include <pthread.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <time.h>
+#include <unistd.h>
+
+
+#define NWRITERS 15
+#define WRITETRIES 10
+#define NREADERS 15
+#define READTRIES 15
+
+#define TIMEOUT 1000000
+#define DELAY 1000000
+
+static pthread_rwlock_t lock = PTHREAD_RWLOCK_WRITER_NONRECURSIVE_INITIALIZER_NP;
+
+
+static void *
+writer_thread (void *nr)
+{
+ struct timespec ts;
+ struct timespec delay;
+ int n;
+
+ ts.tv_sec = 0;
+ ts.tv_nsec = TIMEOUT;
+
+ delay.tv_sec = 0;
+ delay.tv_nsec = DELAY;
+
+ for (n = 0; n < WRITETRIES; ++n)
+ {
+ do
+ {
+ clock_gettime (CLOCK_REALTIME, &ts);
+
+ ts.tv_nsec += 2 * TIMEOUT;
+
+ printf ("writer thread %ld tries again\n", (long int) nr);
+ }
+ //while (pthread_rwlock_wrlock (&lock), 0);
+ while (pthread_rwlock_timedwrlock (&lock, &ts) == ETIMEDOUT);
+
+ printf ("writer thread %ld succeeded\n", (long int) nr);
+
+ nanosleep (&delay, NULL);
+
+ pthread_rwlock_unlock (&lock);
+
+ printf ("writer thread %ld released\n", (long int) nr);
+ }
+
+ return NULL;
+}
+
+
+static void *
+reader_thread (void *nr)
+{
+ struct timespec ts;
+ struct timespec delay;
+ int n;
+
+ delay.tv_sec = 0;
+ delay.tv_nsec = DELAY;
+
+ for (n = 0; n < READTRIES; ++n)
+ {
+ do
+ {
+ clock_gettime (CLOCK_REALTIME, &ts);
+
+ ts.tv_nsec += TIMEOUT;
+
+ printf ("reader thread %ld tries again\n", (long int) nr);
+ }
+ //while (pthread_rwlock_rdlock (&lock), 0);
+ while (pthread_rwlock_timedrdlock (&lock, &ts) == ETIMEDOUT);
+
+ printf ("reader thread %ld succeeded\n", (long int) nr);
+
+ nanosleep (&delay, NULL);
+
+ pthread_rwlock_unlock (&lock);
+
+ printf ("reader thread %ld released\n", (long int) nr);
+ }
+
+ return NULL;
+}
+
+
+int
+main (void)
+{
+ pthread_t thwr[NWRITERS];
+ pthread_t thrd[NREADERS];
+ int n;
+ void *res;
+
+ /* Make standard error the same as standard output. */
+ dup2 (1, 2);
+
+ /* Make sure we see all message, even those on stdout. */
+ setvbuf (stdout, NULL, _IONBF, 0);
+
+ for (n = 0; n < NWRITERS; ++n)
+ {
+ int err = pthread_create (&thwr[n], NULL, writer_thread, (void *) n);
+
+ if (err != 0)
+ error (EXIT_FAILURE, err, "cannot create writer thread");
+ }
+
+ for (n = 0; n < NREADERS; ++n)
+ {
+ int err = pthread_create (&thrd[n], NULL, reader_thread, (void *) n);
+
+ if (err != 0)
+ error (EXIT_FAILURE, err, "cannot create reader thread");
+ }
+
+ /* Wait for all the threads. */
+ for (n = 0; n < NWRITERS; ++n)
+ pthread_join (thwr[n], &res);
+ for (n = 0; n < NREADERS; ++n)
+ pthread_join (thrd[n], &res);
+
+ return 0;
+}