tar-1.29HEADtar-1.29master

1 files changed, 92 insertions, 0 deletions

diff --git a/tests/checkseekhole.c b/tests/checkseekhole.c
new file mode 100644
index 0000000..c7d6204
--- /dev/null
+++ b/tests/checkseekhole.c
@@ -0,0 +1,92 @@
+/* Test suite for GNU tar - SEEK_HOLE detector.
+
+   Copyright 2015-2016 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, 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 <http://www.gnu.org/licenses/>.
+
+   Description:  detect whether it is possible to work with SEEK_HOLE on
+   particular operating system and file system. */
+
+#include "config.h"
+
+#include <sys/stat.h>
+#include <sys/types.h>
+#include <unistd.h>
+#include <stdlib.h>
+#include <fcntl.h>
+
+enum {
+    EX_OK = 0,    /* SEEK_HOLE support */
+    EX_FAIL,      /* test failed - no SEEK_HOLE support */
+    EX_BAD,       /* test is not relevant */
+};
+
+int
+check_seek_hole (int fd)
+{
+#ifdef SEEK_HOLE
+  struct stat stat;
+  off_t offset;
+
+  /* hole of 100MB */
+  if (lseek (fd, 100*1024*1024, SEEK_END) < 0)
+    return EX_BAD;
+
+  /* piece of data */
+  if (write (fd, "data\n", 5) != 5)
+    return EX_BAD;
+
+  /* another hole */
+  if (lseek (fd, 100*1024*1024, SEEK_END) < 0)
+    return EX_BAD;
+
+  /* piece of data */
+  if (write (fd, "data\n", 5) != 5)
+    return EX_BAD;
+
+  if (fstat (fd, &stat))
+    return EX_BAD;
+
+  offset = lseek (fd, 0, SEEK_DATA);
+  if (offset == (off_t)-1)
+    return EX_FAIL;
+
+  offset = lseek (fd, offset, SEEK_HOLE);
+  if (offset == (off_t)-1 || offset == stat.st_size)
+    return EX_FAIL;
+
+  return EX_OK;
+#else
+  return EX_BAD;
+#endif
+}
+
+int
+main ()
+{
+#ifdef SEEK_HOLE
+  int rc;
+  char template[] = "testseekhole-XXXXXX";
+  int fd = mkstemp (template);
+  if (fd == -1)
+    return EX_BAD;
+  rc = check_seek_hole (fd);
+  close (fd);
+  unlink (template);
+
+  return rc;
+#else
+  return EX_FAIL;
+#endif
+}