1 files changed, 144 insertions, 0 deletions
diff --git a/sysdeps/pthread/tst-sem3.c b/sysdeps/pthread/tst-sem3.c
new file mode 100644
index 0000000..6568840
--- /dev/null
+++ b/sysdeps/pthread/tst-sem3.c
@@ -0,0 +1,144 @@
+/* Copyright (C) 2002-2020 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, see
+   <https://www.gnu.org/licenses/>.  */
+
+#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
+do_test (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");
+      return 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) != (ssize_t) ps)
+    {
+      puts ("short write");
+      return 1;
+    }
+
+  mem = mmap (NULL, ps, PROT_READ | PROT_WRITE, MAP_SHARED, fd, 0);
+  if (mem == MAP_FAILED)
+    {
+      printf ("mmap failed: %m\n");
+      return 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");
+      return 1;
+    }
+
+  if (TEMP_FAILURE_RETRY (sem_wait (s)) == -1)
+    {
+      puts ("1st wait failed");
+      return 1;
+    }
+
+  errno = 0;
+  if (TEMP_FAILURE_RETRY (sem_trywait (s)) != -1)
+    {
+      puts ("trywait succeeded");
+      return 1;
+    }
+  else if (errno != EAGAIN)
+    {
+      puts ("trywait didn't return EAGAIN");
+      return 1;
+    }
+
+  *p = 0;
+
+  puts ("going to fork now");
+  pid = fork ();
+  if (pid == -1)
+    {
+      puts ("fork failed");
+      return 1;
+    }
+  else if (pid == 0)
+    {
+      /* Play some lock ping-pong.  It's our turn to unlock first.  */
+      if ((*p)++ != 0)
+	{
+	  puts ("child: *p != 0");
+	  return 1;
+	}
+
+      if (sem_post (s) == -1)
+	{
+	  puts ("child: 1st post failed");
+	  return 1;
+	}
+
+      puts ("child done");
+    }
+  else
+    {
+      if (TEMP_FAILURE_RETRY (sem_wait (s)) == -1)
+	{
+	  printf ("parent: 2nd wait failed: %m\n");
+	  return 1;
+	}
+
+      if (*p != 1)
+	{
+	  puts ("*p != 1");
+	  return 1;
+	}
+
+      puts ("parent done");
+    }
+
+  return 0;
+}
+
+#define TEST_FUNCTION do_test ()
+#include "../test-skeleton.c"