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authorpatacongo <patacongo@42af7a65-404d-4744-a932-0658087f49c3>2011-04-28 19:26:46 +0000
committerpatacongo <patacongo@42af7a65-404d-4744-a932-0658087f49c3>2011-04-28 19:26:46 +0000
commitf5deadfbb2ea797607ce7646c2bca1fdfe74c3c2 (patch)
tree7b25391c6c8172936f0c27efae5b40503b7d03c4 /nuttx/fs/nxffs/nxffs_util.c
parentb501edd4c0f7b4fffc6d187ee5e0bd862d381a79 (diff)
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Add first NXFFS files
git-svn-id: svn://svn.code.sf.net/p/nuttx/code/trunk@3536 42af7a65-404d-4744-a932-0658087f49c3
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1 files changed, 112 insertions, 0 deletions
diff --git a/nuttx/fs/nxffs/nxffs_util.c b/nuttx/fs/nxffs/nxffs_util.c
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+/****************************************************************************
+ * fs/nxffs/nxffs_util.c
+ *
+ * Copyright (C) 2011 Gregory Nutt. All rights reserved.
+ * Author: Gregory Nutt <spudmonkey@racsa.co.cr>
+ *
+ * References: Linux/Documentation/filesystems/romfs.txt
+ *
+ * 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.
+ *
+ ****************************************************************************/
+
+/****************************************************************************
+ * Included Files
+ ****************************************************************************/
+
+#include <nuttx/config.h>
+
+#include <string.h>
+#include <errno.h>
+#include <assert.h>
+#include <debug.h>
+
+#include <nuttx/mtd.h>
+
+#include "nxffs.h"
+
+/****************************************************************************
+ * Pre-processor Definitions
+ ****************************************************************************/
+
+/****************************************************************************
+ * Public Types
+ ****************************************************************************/
+
+/****************************************************************************
+ * Public Variables
+ ****************************************************************************/
+
+/****************************************************************************
+ * Private Functions
+ ****************************************************************************/
+
+/****************************************************************************
+ * Public Functions
+ ****************************************************************************/
+
+/****************************************************************************
+ * Name: nxffs_rdle16
+ *
+ * Description:
+ * Get a (possibly unaligned) 16-bit little endian value.
+ *
+ * Input Parameters:
+ * val - A pointer to the first byte of the little endian value.
+ *
+ * Returned Values:
+ * A uint16_t representing the whole 16-bit integer value
+ *
+ ****************************************************************************/
+
+uint16_t nxffs_rdle16(const uint8_t *val)
+{
+ return (uint16_t)val[1] << 8 | (uint16_t)val[0];
+}
+
+/****************************************************************************
+ * Name: nxffs_rdle32
+ *
+ * Description:
+ * Get a (possibly unaligned) 32-bit little endian value.
+ *
+ * Input Parameters:
+ * val - A pointer to the first byte of the little endian value.
+ *
+ * Returned Values:
+ * A uint32_t representing the whole 32-bit integer value
+ *
+ ****************************************************************************/
+
+uint32_t nxffs_rdle32(const uint8_t *val)
+{
+ /* Little endian means LS halfword first in byte stream */
+
+ return (uint32_t)nxffs_rdle16(&val[2]) << 16 | (uint32_t)nxffs_rdle16(val);
+}
+