Add support for block drivers

git-svn-id: svn://svn.code.sf.net/p/nuttx/code/trunk@206 42af7a65-404d-4744-a932-0658087f49c3

1 files changed, 206 insertions, 0 deletions

diff --git a/nuttx/fs/fs_inodereserve.c b/nuttx/fs/fs_inodereserve.c
new file mode 100644
index 000000000..ad010e21e
--- /dev/null
+++ b/nuttx/fs/fs_inodereserve.c
@@ -0,0 +1,206 @@
+/************************************************************
+ * fs_registerreserve.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 <stdlib.h>
+#include <errno.h>
+#include <nuttx/fs.h>
+#include "fs_internal.h"
+
+/************************************************************
+ * Definitions
+ ************************************************************/
+
+/************************************************************
+ * Private Variables
+ ************************************************************/
+
+/************************************************************
+ * Public Variables
+ ************************************************************/
+
+/************************************************************
+ * Private Functions
+ ************************************************************/
+
+/************************************************************
+ * Name: inode_namelen
+ ************************************************************/
+
+static int inode_namelen(const char *name)
+{
+  const char *tmp = name;
+  while(*tmp && *tmp != '/') tmp++;
+  return tmp - name;
+}
+
+/************************************************************
+ * Name: inode_namecpy
+ ************************************************************/
+
+static void inode_namecpy(char *dest, const char *src)
+{
+  while(*src && *src != '/') *dest++ = *src++;
+  *dest='\0';
+}
+
+/************************************************************
+ * Name: inode_alloc
+ ************************************************************/
+
+static FAR struct inode *inode_alloc(const char *name)
+{
+  int namelen = inode_namelen(name);
+  FAR struct inode *node = (FAR struct inode*)zalloc(FSNODE_SIZE(namelen));
+  if (node)
+    {
+      inode_namecpy(node->i_name, name);
+    }
+  return node;
+}
+
+/************************************************************
+ * Name: inode_insert
+ ************************************************************/
+
+static void inode_insert(FAR struct inode *node,
+                         FAR struct inode *peer,
+                         FAR struct inode *parent)
+{
+  /* If peer is non-null, then new node simply goes to the right
+   * of that peer node.
+   */
+
+   if (peer)
+     {
+       node->i_peer = peer->i_peer;
+       peer->i_peer = node;
+     }
+
+   /* If parent is non-null, then it must go at the head of its
+    * list of children.
+    */
+
+   else if (parent)
+     {
+       node->i_peer    = parent->i_child;
+       parent->i_child = node;
+     }
+
+   /* Otherwise, this must be the new root_inode */
+
+   else
+     {
+       node->i_peer = root_inode;
+       root_inode   = node;
+     }
+}
+
+/************************************************************
+ * Public Functions
+ ************************************************************/
+
+/************************************************************
+ * Name: inode_reserve
+ ************************************************************/
+
+FAR struct inode *inode_reserve(const char *path)
+{
+  const char       *name = path;
+  FAR struct inode *left;
+  FAR struct inode *parent;
+
+  if (!*path || path[0] != '/')
+    {
+      return NULL;
+    }
+
+  /* Find the location to insert the new subtree */
+
+  if (inode_search(&name, &left, &parent, NULL) != NULL)
+    {
+      /* Is is an error if the node already exists in the tree */
+
+      return NULL;
+    }
+
+  /* Now we now where to insert the subtree */
+
+  for (;;)
+    {
+      FAR struct inode *node;
+
+      /* Create a new node -- we need to know if this is the
+       * the leaf node or some intermediary.  We can find this
+       * by looking at the next name.
+       */
+
+      const char *next_name = inode_nextname(name);
+      if (*next_name)
+        {
+          /* Insert an operationless node */
+
+          node = inode_alloc(name);
+          if (node)
+            {
+              inode_insert(node, left, parent);
+
+              /* Set up for the next time through the loop */
+
+              name   = next_name;
+              left   = NULL;
+              parent = node;
+              continue;
+            }
+        }
+      else
+        {
+          node = inode_alloc(name);
+          if (node)
+            {
+              inode_insert(node, left, parent);
+              return node;
+            }
+        }
+
+      /* We get here on failures to allocate node memory */
+      return NULL;
+    }
+}