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-rw-r--r--nptl/tst-sem3.c142
1 files changed, 142 insertions, 0 deletions
diff --git a/nptl/tst-sem3.c b/nptl/tst-sem3.c
new file mode 100644
index 0000000000..7d3f68f019
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+++ b/nptl/tst-sem3.c
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+/* Copyright (C) 2002 Free Software Foundation, Inc.
+ This file is part of the GNU C Library.
+ Contributed by Ulrich Drepper <drepper@redhat.com>, 2002.
+
+ The GNU C Library is free software; you can redistribute it and/or
+ modify it under the terms of the GNU Lesser General Public
+ License as published by the Free Software Foundation; either
+ version 2.1 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
+ Lesser General Public License for more details.
+
+ You should have received a copy of the GNU Lesser General Public
+ License along with the GNU C Library; if not, write to the Free
+ Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
+ 02111-1307 USA. */
+
+#include <errno.h>
+#include <semaphore.h>
+#include <stdint.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <unistd.h>
+#include <sys/mman.h>
+#include <sys/wait.h>
+
+
+int
+main (void)
+{
+ size_t ps = sysconf (_SC_PAGESIZE);
+ char tmpfname[] = "/tmp/tst-sem3.XXXXXX";
+ char data[ps];
+ void *mem;
+ int fd;
+ sem_t *s;
+ pid_t pid;
+ char *p;
+
+ fd = mkstemp (tmpfname);
+ if (fd == -1)
+ {
+ printf ("cannot open temporary file: %m\n");
+ exit (1);
+ }
+
+ /* Make sure it is always removed. */
+ unlink (tmpfname);
+
+ /* Create one page of data. */
+ memset (data, '\0', ps);
+
+ /* Write the data to the file. */
+ if (write (fd, data, ps) != ps)
+ {
+ puts ("short write");
+ exit (1);
+ }
+
+ mem = mmap (NULL, ps, PROT_READ | PROT_WRITE, MAP_SHARED, fd, 0);
+ if (mem == MAP_FAILED)
+ {
+ printf ("mmap failed: %m\n");
+ exit (1);
+ }
+
+ s = (sem_t *) (((uintptr_t) mem + __alignof (sem_t))
+ & ~(__alignof (sem_t) - 1));
+ p = (char *) (s + 1);
+
+ if (sem_init (s, 1, 1) == -1)
+ {
+ puts ("init failed");
+ exit (1);
+ }
+
+ if (TEMP_FAILURE_RETRY (sem_wait (s)) == -1)
+ {
+ puts ("1st wait failed");
+ exit (1);
+ }
+
+ errno = 0;
+ if (TEMP_FAILURE_RETRY (sem_trywait (s)) != -1)
+ {
+ puts ("trywait succeeded");
+ exit (1);
+ }
+ else if (errno != EAGAIN)
+ {
+ puts ("trywait didn't return EAGAIN");
+ exit (1);
+ }
+
+ *p = 0;
+
+ puts ("going to fork now");
+ pid = fork ();
+ if (pid == -1)
+ {
+ puts ("fork failed");
+ exit (1);
+ }
+ else if (pid == 0)
+ {
+ /* Play some lock ping-pong. It's our turn to unlock first. */
+ if ((*p)++ != 0)
+ {
+ puts ("child: *p != 0");
+ exit (1);
+ }
+
+ if (sem_post (s) == -1)
+ {
+ puts ("child: 1st post failed");
+ exit (1);
+ }
+
+ puts ("child done");
+ }
+ else
+ {
+ if (TEMP_FAILURE_RETRY (sem_wait (s)) == -1)
+ {
+ printf ("parent: 2nd wait failed: %m\n");
+ exit (1);
+ }
+
+ if (*p != 1)
+ {
+ puts ("*p != 1");
+ exit (1);
+ }
+
+ puts ("parent done");
+ }
+
+ exit (0);
+}