1 files changed, 94 insertions, 0 deletions
diff --git a/cpukit/libcsupport/src/lseek.c b/cpukit/libcsupport/src/lseek.c
new file mode 100644
index 0000000000..3f37029807
--- /dev/null
+++ b/cpukit/libcsupport/src/lseek.c
@@ -0,0 +1,94 @@
+/*
+ *  lseek() - POSIX 1003.1b 6.5.3 - Reposition Read/Write File Offset
+ *
+ *  COPYRIGHT (c) 1989-1999.
+ *  On-Line Applications Research Corporation (OAR).
+ *
+ *  The license and distribution terms for this file may be
+ *  found in the file LICENSE in this distribution or at
+ *  http://www.rtems.com/license/LICENSE.
+ *
+ *  $Id$
+ */
+
+#if HAVE_CONFIG_H
+#include "config.h"
+#endif
+
+#include <stdio.h>
+
+#include <rtems/libio_.h>
+#include <rtems/seterr.h>
+
+off_t lseek(
+  int     fd,
+  off_t   offset,
+  int     whence
+)
+{
+  rtems_libio_t *iop;
+  off_t          old_offset;
+  off_t          status;
+
+  rtems_libio_check_fd( fd );
+  iop = rtems_libio_iop( fd );
+  rtems_libio_check_is_open(iop);
+
+  /*
+   *  Now process the lseek().
+   */
+
+  old_offset = iop->offset;
+  switch ( whence ) {
+    case SEEK_SET:
+      iop->offset = offset;
+      break;
+
+    case SEEK_CUR:
+      iop->offset += offset;
+      break;
+
+    case SEEK_END:
+      iop->offset = iop->size + offset;
+      break;
+
+    default:
+      rtems_set_errno_and_return_minus_one( EINVAL );
+  }
+
+  /*
+   *  At this time, handlers assume iop->offset has the desired
+   *  new offset.
+   */
+
+  status = (*iop->pathinfo.handlers->lseek_h)( iop, offset, whence );
+  if ( status == (off_t) -1 )
+    iop->offset = old_offset;
+
+  /*
+   *  So if the operation failed, we have to restore iop->offset.
+   */
+
+  return status;
+}
+
+/*
+ *  _lseek_r
+ *
+ *  This is the Newlib dependent reentrant version of lseek().
+ */
+
+#if defined(RTEMS_NEWLIB) && !defined(HAVE__LSEEK_R)
+
+#include <reent.h>
+
+off_t _lseek_r(
+  struct _reent *ptr __attribute__((unused)),
+  int            fd,
+  off_t          offset,
+  int            whence
+)
+{
+  return lseek( fd, offset, whence );
+}
+#endif