Added opendir, readdir, closedir, etc.

git-svn-id: svn://svn.code.sf.net/p/nuttx/code/trunk@62 42af7a65-404d-4744-a932-0658087f49c3

1 files changed, 145 insertions, 0 deletions

diff --git a/nuttx/fs/fs_readdir.c b/nuttx/fs/fs_readdir.c
new file mode 100644
index 000000000..40f4f1747
--- /dev/null
+++ b/nuttx/fs/fs_readdir.c
@@ -0,0 +1,145 @@
+/************************************************************
+ * fs_readdir.c
+ *
+ *   Copyright (C) 2007 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 Gregory Nutt 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 <sys/types.h>
+#include <string.h>
+#include <dirent.h>
+#include <errno.h>
+#include <nuttx/fs.h>
+#include "fs_internal.h"
+
+/************************************************************
+ * Private Functions
+ ************************************************************/
+
+/************************************************************
+ * Public Functions
+ ************************************************************/
+
+/************************************************************
+ * Name: readdir
+ *
+ * Description:
+ *   The readdir() function returns a pointer to a dirent
+ *   structure representing the next directory entry in the
+ *   directory stream pointed to by dir.  It returns NULL on
+ *   reaching the end-of-file or if an error occurred.
+ *
+ * Inputs:
+ *   dirp -- An instance of type DIR created by a previous
+ *     call to opendir();
+ *
+ * Return:
+ *   The readdir() function returns a pointer to a dirent
+ *   structure, or NULL if an error occurs or end-of-file
+ *   is reached.  On error, errno is set appropriately.
+ *
+ *   EBADF   - Invalid directory stream descriptor dir
+ *
+ ************************************************************/
+
+#if CONFIG_NFILE_DESCRIPTORS > 0
+
+FAR struct dirent *readdir(DIR *dirp)
+{
+  FAR struct internal_dir_s *idir = (struct internal_dir_s *)dirp;
+  FAR struct inode *prev;
+
+  if (!idir)
+    {
+      *get_errno_ptr() = EBADF;
+      return NULL;
+    }
+
+  /* Check if we are at the end of the list */
+
+  if (!idir->next)
+    {
+      return NULL;
+    }
+
+  /* Copy the inode name into the dirent structure */
+
+  strncpy(idir->dir.d_name, idir->next->i_name, NAME_MAX+1);
+
+  /* If the node has file operations, we will say that it is
+   * a file.
+   */
+
+  idir->dir.d_type = 0;
+  if (idir->next->i_ops)
+    {
+      idir->dir.d_type |= DTYPE_FILE;
+    }
+
+  /* If the node has child node(s), then we will say that it
+   * is a directory.  NOTE: that the node can be both!
+   */
+
+  if (idir->next->i_child || !idir->next->i_ops)
+    {
+      idir->dir.d_type |= DTYPE_FILE;
+    }
+
+  /* Now get the inode to vist next time that readdir() is called */
+
+  inode_semtake();
+
+  prev       = idir->next;
+  idir->next = prev->i_peer; /* The next node to visit */
+
+  if (idir->next)
+    {
+      /* Increment the reference count on this next node */
+
+      idir->next->i_crefs++;
+    }
+
+  inode_semgive();
+
+  if (prev)
+    {
+      inode_release(prev);
+    }
+
+  return &idir->dir;
+}
+
+#endif /* CONFIG_NFILE_DESCRIPTORS */