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-rw-r--r--posix/tst-fork.c136
1 files changed, 136 insertions, 0 deletions
diff --git a/posix/tst-fork.c b/posix/tst-fork.c
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+/* Tests for fork.
+   Copyright (C) 2000 Free Software Foundation, Inc.
+   Contributed by Ulrich Drepper <drepper@cygnus.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 <stdlib.h>
+#include <string.h>
+#include <unistd.h>
+#include <wait.h>
+
+
+static const char testdata[] = "This is a test";
+static const char testdata2[] = "And here we go again";
+
+
+int
+main (void)
+{
+  const char *tmpdir = getenv ("TMPDIR");
+  char buf[100];
+  size_t tmpdirlen;
+  char *name;
+  int fd;
+  pid_t pid;
+  off_t off;
+  int status;
+
+  if (tmpdir == NULL || *tmpdir == '\0')
+    tmpdir = "/tmp";
+  tmpdirlen = strlen (tmpdir);
+
+  name = (char *) malloc (tmpdirlen + strlen ("/forkXXXXXX") + 1);
+  if (name == NULL)
+    error (EXIT_FAILURE, errno, "cannot allocate file name");
+
+  mempcpy (mempcpy (name, tmpdir, tmpdirlen),
+	   "/forkXXXXXX", sizeof ("/forkXXXXXX"));
+
+  /* Open our test file.   */
+  fd = mkstemp (name);
+  if (fd == -1)
+     error (EXIT_FAILURE, errno, "cannot open test file `%s'", name);
+
+  /* Make sure it gets removed.  */
+  unlink (name);
+
+  /* Write some data.  */
+  if (write (fd, testdata, strlen (testdata)) != strlen (testdata))
+    error (EXIT_FAILURE, errno, "cannot write test data");
+
+  /* Get the position in the stream.  */
+  off = lseek (fd, 0, SEEK_CUR);
+  if (off == (off_t) -1 || off != strlen (testdata))
+    error (EXIT_FAILURE, errno, "wrong file position");
+
+  /* Now fork of the process.  */
+  pid = fork ();
+  if (pid == 0)
+    {
+      /* This is the child.  First get the position of the descriptor.  */
+      off = lseek (fd, 0, SEEK_CUR);
+      if (off == (off_t) -1 || off != strlen (testdata))
+	error (EXIT_FAILURE, errno, "wrong file position in child");
+
+      /* Reset the position.  */
+      if (lseek (fd, 0, SEEK_SET) != 0)
+	error (EXIT_FAILURE, errno, "cannot reset position in child");
+
+      /* Read the data.  */
+      if (read (fd, buf, sizeof buf) != strlen (testdata))
+	error (EXIT_FAILURE, errno, "cannot read data in child");
+
+      /* Compare the data.  */
+      if (memcmp (buf, testdata, strlen (testdata)) != 0)
+	error (EXIT_FAILURE, 0, "data comparison failed in child");
+
+      /* Reset position again.  */
+      if (lseek (fd, 0, SEEK_SET) != 0)
+	error (EXIT_FAILURE, errno, "cannot reset position again in child");
+
+      /* Write new data.  */
+      if (write (fd, testdata2, strlen (testdata2)) != strlen (testdata2))
+	error (EXIT_FAILURE, errno, "cannot write new data in child");
+
+      /* Close the file.  This must not remove it.  */
+      close (fd);
+
+      _exit (0);
+    }
+  else if (pid < 0)
+    /* Something went wrong.  */
+    error (EXIT_FAILURE, errno, "cannot fork");
+
+  /* Wait for the child.  */
+  if (waitpid (pid, &status, 0) != pid)
+    error (EXIT_FAILURE, 0, "Oops, wrong test program terminated");
+
+  if (WTERMSIG (status) != 0)
+    error (EXIT_FAILURE, 0, "Child terminated incorrectly");
+  status = WEXITSTATUS (status);
+
+  if (status == 0)
+    {
+      /* Test whether the child wrote the right data.  First test the
+	 position.  It must be the same as in the child.  */
+      if (lseek (fd, 0, SEEK_CUR) != strlen (testdata2))
+	error (EXIT_FAILURE, 0, "file position not changed");
+
+      if (lseek (fd, 0, SEEK_SET) != 0)
+	error (EXIT_FAILURE, errno, "cannot reset file position");
+
+      if (read (fd, buf, sizeof buf) != strlen (testdata2))
+	error (EXIT_FAILURE, errno, "cannot read new data");
+
+      if (memcmp (buf, testdata2, strlen (testdata2)) != 0)
+	error (EXIT_FAILURE, 0, "new data not read correctly");
+    }
+
+  return status;
+}