Various fixes for buffered R/W I/O and seeking

git-svn-id: svn://svn.code.sf.net/p/nuttx/code/trunk@630 42af7a65-404d-4744-a932-0658087f49c3

1 files changed, 111 insertions, 0 deletions

diff --git a/nuttx/lib/lib_wrflush.c b/nuttx/lib/lib_wrflush.c
new file mode 100644
index 000000000..cc2f65543
--- /dev/null
+++ b/nuttx/lib/lib_wrflush.c
@@ -0,0 +1,111 @@
+/****************************************************************************
+ * lib/lib_wrlush.c
+ *
+ *   Copyright (C) 2008 Gregory Nutt. All rights reserved.
+ *   Author: Gregory Nutt <spudmonkey@racsa.co.cr>
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in
+ *    the documentation and/or other materials provided with the
+ *    distribution.
+ * 3. Neither the name NuttX nor the names of its contributors may be
+ *    used to endorse or promote products derived from this software
+ *    without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
+ * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
+ * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
+ * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
+ * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
+ * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
+ * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+ * POSSIBILITY OF SUCH DAMAGE.
+ *
+ ****************************************************************************/
+
+/****************************************************************************
+ * Compilation Switches
+ ****************************************************************************/
+
+/****************************************************************************
+ * Included Files
+ ****************************************************************************/
+
+#include <nuttx/config.h>
+
+#include <sys/types.h>
+#include <fcntl.h>
+#include <errno.h>
+
+#include "lib_internal.h"
+
+/****************************************************************************
+ * Definitions
+ ****************************************************************************/
+
+/****************************************************************************
+ * Private Type Declarations
+ ****************************************************************************/
+
+/****************************************************************************
+ * Private Function Prototypes
+ ****************************************************************************/
+
+/****************************************************************************
+ * Global Constant Data
+ ****************************************************************************/
+
+/****************************************************************************
+ * Global Variables
+ ****************************************************************************/
+
+/****************************************************************************
+ * Private Constant Data
+ ****************************************************************************/
+
+/****************************************************************************
+ * Private Variables
+ ****************************************************************************/
+
+/****************************************************************************
+ * Global Functions
+ ****************************************************************************/
+
+/****************************************************************************
+ * Name: lib_wrflush
+ *
+ * Description:
+ *   This is simply a version of fflush that does not report an error if
+ *   the file is not open for writing.
+ *
+ ****************************************************************************/
+
+/****************************************************************************
+ * Name: lib_wrflush
+ ****************************************************************************/
+
+int lib_wrflush(FILE *stream)
+{
+#if CONFIG_STDIO_BUFFER_SIZE > 0
+  /* Verify that the stream is opened for writing... flush will return an
+   * error if it is called for a stream that is not opened for writing.
+   */
+
+  if (stream && (stream->fs_oflags & O_WROK) != 0)
+    {
+      return fflush(stream);
+    }
+#endif
+  return OK;
+}
+