procfs/: Extenstive architectural changes and enhancements by Ken Pettit

2 files changed, 461 insertions, 1 deletions

diff --git a/nuttx/fs/smartfs/Make.defs b/nuttx/fs/smartfs/Make.defs
index 9604d546f..b77e1cfd3 100644
--- a/nuttx/fs/smartfs/Make.defs
+++ b/nuttx/fs/smartfs/Make.defs
@@ -38,7 +38,7 @@ ifeq ($(CONFIG_FS_SMARTFS),y)
 # Files required for SmartFS file system support
 
 ASRCS +=
-CSRCS += smartfs_smart.c smartfs_utils.c
+CSRCS += smartfs_smart.c smartfs_utils.c smartfs_procfs.c
 
 # Files required for mksmartfs utility function
 
diff --git a/nuttx/fs/smartfs/smartfs_procfs.c b/nuttx/fs/smartfs/smartfs_procfs.c
new file mode 100644
index 000000000..64f7101d4
--- /dev/null
+++ b/nuttx/fs/smartfs/smartfs_procfs.c
@@ -0,0 +1,460 @@
+/****************************************************************************
+ * fs/smartfs/smartfs_procfs.c
+ *
+ *   Copyright (C) 2013 Ken Pettit. All rights reserved.
+ *   Author: Ken Pettit <pettitkd@gmail.com>
+ *
+ * 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 <sys/types.h>
+#include <sys/statfs.h>
+#include <sys/stat.h>
+
+#include <stdint.h>
+#include <stdbool.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <fcntl.h>
+#include <assert.h>
+#include <errno.h>
+#include <debug.h>
+
+#include <nuttx/arch.h>
+#include <nuttx/sched.h>
+#include <nuttx/kmalloc.h>
+#include <nuttx/fs/fs.h>
+#include <nuttx/fs/procfs.h>
+#include <nuttx/fs/dirent.h>
+
+#include <arch/irq.h>
+
+#if defined(CONFIG_FS_PROCFS) && !defined(CONFIG_FS_EXCLUDE_SMARTFS)
+
+/****************************************************************************
+ * Pre-processor Definitions
+ ****************************************************************************/
+
+/****************************************************************************
+ * Private Types
+ ****************************************************************************/
+/* This enumeration identifies all of the thread attributes that can be
+ * accessed via the procfs file system.
+ */
+
+/* This structure describes one open "file" */
+
+struct smartfs_file_s
+{
+  struct procfs_file_s  base;        /* Base open file structure */
+
+  /* Add context specific data types for managing an open file here */
+};
+
+/* Level 1 is the directory of attributes */
+
+struct smartfs_level1_s
+{
+  struct procfs_dir_priv_s  base;    /* Base directory private data */
+
+  /* Add context specific data types here for managing the directory
+   * open / read / stat, etc.
+   */
+
+};
+
+/****************************************************************************
+ * Private Function Prototypes
+ ****************************************************************************/
+/* File system methods */
+
+static int     smartfs_open(FAR struct file *filep, FAR const char *relpath,
+                 int oflags, mode_t mode);
+static int     smartfs_close(FAR struct file *filep);
+static ssize_t smartfs_read(FAR struct file *filep, FAR char *buffer,
+                 size_t buflen);
+
+static int     smartfs_dup(FAR const struct file *oldp,
+                 FAR struct file *newp);
+
+static int     smartfs_opendir(const char *relpath, FAR struct fs_dirent_s *dir);
+static int     smartfs_closedir(FAR struct fs_dirent_s *dir);
+static int     smartfs_readdir(FAR struct fs_dirent_s *dir);
+static int     smartfs_rewinddir(FAR struct fs_dirent_s *dir);
+
+static int     smartfs_stat(FAR const char *relpath, FAR struct stat *buf);
+
+/****************************************************************************
+ * Private Variables
+ ****************************************************************************/
+
+/****************************************************************************
+ * Public Variables
+ ****************************************************************************/
+
+/* See include/nutts/fs/procfs.h
+ * We use the old-fashioned kind of initializers so that this will compile
+ * with any compiler.
+ */
+
+const struct procfs_operations smartfs_procfsoperations =
+{
+  smartfs_open,       /* open */
+  smartfs_close,      /* close */
+  smartfs_read,       /* read */
+
+  /* TODO:  Decide if this deiver supports write */
+  NULL,            /* write */
+
+  smartfs_dup,        /* dup */
+
+  smartfs_opendir,    /* opendir */
+  smartfs_closedir,   /* closedir */
+  smartfs_readdir,    /* readdir */
+  smartfs_rewinddir,  /* rewinddir */
+
+  smartfs_stat        /* stat */
+};
+
+/****************************************************************************
+ * Private Functions
+ ****************************************************************************/
+
+/****************************************************************************
+ * Name: smartfs_open
+ ****************************************************************************/
+
+static int smartfs_open(FAR struct file *filep, FAR const char *relpath,
+                      int oflags, mode_t mode)
+{
+  FAR struct smartfs_file_s *priv;
+
+  fvdbg("Open '%s'\n", relpath);
+
+  /* PROCFS is read-only.  Any attempt to open with any kind of write
+   * access is not permitted.
+   *
+   * REVISIT:  Write-able proc files could be quite useful.
+   */
+
+  if (((oflags & O_WRONLY) != 0 || (oflags & O_RDONLY) == 0) &&
+      (smartfs_procfsoperations.write == NULL))
+    {
+      fdbg("ERROR: Only O_RDONLY supported\n");
+      return -EACCES;
+    }
+
+  /* Allocate a container to hold the task and attribute selection */
+
+  priv = (FAR struct smartfs_file_s *)kzalloc(sizeof(struct smartfs_file_s));
+  if (!priv)
+    {
+      fdbg("ERROR: Failed to allocate file attributes\n");
+      return -ENOMEM;
+    }
+
+  /* TODO: Initialize the context specific data here */
+
+
+  /* Save the index as the open-specific state in filep->f_priv */
+
+  filep->f_priv = (FAR void *)priv;
+  return OK;
+}
+
+/****************************************************************************
+ * Name: smartfs_close
+ ****************************************************************************/
+
+static int smartfs_close(FAR struct file *filep)
+{
+  FAR struct smartfs_file_s *priv;
+
+  /* Recover our private data from the struct file instance */
+
+  priv = (FAR struct smartfs_file_s *)filep->f_priv;
+  DEBUGASSERT(priv);
+
+  /* Release the file attributes structure */
+
+  kfree(priv);
+  filep->f_priv = NULL;
+  return OK;
+}
+
+/****************************************************************************
+ * Name: smartfs_read
+ ****************************************************************************/
+
+static ssize_t smartfs_read(FAR struct file *filep, FAR char *buffer,
+                           size_t buflen)
+{
+  FAR struct smartfs_file_s *priv;
+  ssize_t ret;
+
+  fvdbg("buffer=%p buflen=%d\n", buffer, (int)buflen);
+
+  /* Recover our private data from the struct file instance */
+
+  priv = (FAR struct smartfs_file_s *)filep->f_priv;
+  DEBUGASSERT(priv);
+
+  /* TODO: Provide the requested data */
+
+  ret = 0;
+
+  /* Update the file offset */
+
+  if (ret > 0)
+    {
+      filep->f_pos += ret;
+    }
+
+  return ret;
+}
+
+/****************************************************************************
+ * Name: smartfs_dup
+ *
+ * Description:
+ *   Duplicate open file data in the new file structure.
+ *
+ ****************************************************************************/
+
+static int smartfs_dup(FAR const struct file *oldp, FAR struct file *newp)
+{
+  FAR struct smartfs_file_s *oldpriv;
+  FAR struct smartfs_file_s *newpriv;
+
+  fvdbg("Dup %p->%p\n", oldp, newp);
+
+  /* Recover our private data from the old struct file instance */
+
+  oldpriv = (FAR struct smartfs_file_s *)oldp->f_priv;
+  DEBUGASSERT(oldpriv);
+
+  /* Allocate a new container to hold the task and attribute selection */
+
+  newpriv = (FAR struct smartfs_file_s *)kzalloc(sizeof(struct smartfs_file_s));
+  if (!newpriv)
+    {
+      fdbg("ERROR: Failed to allocate file attributes\n");
+      return -ENOMEM;
+    }
+
+  /* The copy the file attribtes from the old attributes to the new */
+
+  memcpy(newpriv, oldpriv, sizeof(struct smartfs_file_s));
+
+  /* Save the new attributes in the new file structure */
+
+  newp->f_priv = (FAR void *)newpriv;
+  return OK;
+}
+
+/****************************************************************************
+ * Name: smartfs_opendir
+ *
+ * Description:
+ *   Open a directory for read access
+ *
+ ****************************************************************************/
+
+static int smartfs_opendir(FAR const char *relpath, FAR struct fs_dirent_s *dir)
+{
+  FAR struct smartfs_level1_s *level1;
+
+  fvdbg("relpath: \"%s\"\n", relpath ? relpath : "NULL");
+  DEBUGASSERT(relpath && dir && !dir->u.procfs);
+
+  /* The path refers to the 1st level sbdirectory.  Allocate the level1
+   * dirent structure.
+   */
+
+  level1 = (FAR struct smartfs_level1_s *)
+     kzalloc(sizeof(struct smartfs_level1_s));
+
+  if (!level1)
+    {
+      fdbg("ERROR: Failed to allocate the level1 directory structure\n");
+      return -ENOMEM;
+    }
+
+  /* TODO:  Initialze context specific data */
+
+
+  /* Initialze base structure components */
+
+  level1->base.level    = 1;
+  level1->base.nentries = 0;
+  level1->base.index    = 0;
+
+  dir->u.procfs = (FAR void *) level1;
+  return OK;
+}
+
+/****************************************************************************
+ * Name: smartfs_closedir
+ *
+ * Description: Close the directory listing
+ *
+ ****************************************************************************/
+
+static int smartfs_closedir(FAR struct fs_dirent_s *dir)
+{
+  FAR struct smartfs_level1_s *priv;
+
+  DEBUGASSERT(dir && dir->u.procfs);
+  priv = dir->u.procfs;
+
+  if (priv)
+    {
+      kfree(priv);
+    }
+
+  dir->u.procfs = NULL;
+  return OK;
+}
+
+/****************************************************************************
+ * Name: smartfs_readdir
+ *
+ * Description: Read the next directory entry
+ *
+ ****************************************************************************/
+
+static int smartfs_readdir(struct fs_dirent_s *dir)
+{
+  FAR struct smartfs_level1_s *level1;
+  char  filename[16];
+  int ret, index;
+
+  DEBUGASSERT(dir && dir->u.procfs);
+  level1 = dir->u.procfs;
+
+  /* TODO: Perform device specific readdir function here.  This may
+   *       or may not involve validating the nentries variable
+   *       in the base depending on the implementation.
+   */
+
+  /* Have we reached the end of the directory */
+
+  index = level1->base.index;
+  if (index >= level1->base.nentries)
+    {
+      /* We signal the end of the directory by returning the special
+       * error -ENOENT
+       */
+
+      fvdbg("Entry %d: End of directory\n", index);
+      ret = -ENOENT;
+    }
+
+  /* We are tranversing a subdirectory of task attributes */
+
+  else
+    {
+      DEBUGASSERT(level1->base.level == 1);
+
+      /* TODO: Add device specific entries */
+
+      strcpy(filename, "dummy");
+
+      /* TODO:  Specify the type of entry */
+
+      dir->fd_dir.d_type = DTYPE_FILE;
+      strncpy(dir->fd_dir.d_name, filename, NAME_MAX+1);
+
+      /* Set up the next directory entry offset.  NOTE that we could use the
+       * standard f_pos instead of our own private index.
+       */
+
+      ret = OK;
+    }
+
+  return ret;
+}
+
+/****************************************************************************
+ * Name: smartfs_rewindir
+ *
+ * Description: Reset directory read to the first entry
+ *
+ ****************************************************************************/
+
+static int smartfs_rewinddir(struct fs_dirent_s *dir)
+{
+  FAR struct smartfs_level1_s *priv;
+
+  DEBUGASSERT(dir && dir->u.procfs);
+  priv = dir->u.procfs;
+
+  priv->base.index = 0;
+  return OK;
+}
+
+/****************************************************************************
+ * Name: smartfs_stat
+ *
+ * Description: Return information about a file or directory
+ *
+ ****************************************************************************/
+
+static int smartfs_stat(const char *relpath, struct stat *buf)
+{
+  int ret = -ENOENT;
+
+  /* TODO:  Decide if the relpath is valid and if it is a file
+   *        or a directory and set it's permissions.
+   */
+
+  buf->st_mode = S_IFDIR|S_IROTH|S_IRGRP|S_IRUSR;
+  ret = OK;
+
+  /* File/directory size, access block size */
+
+  buf->st_size    = 0;
+  buf->st_blksize = 0;
+  buf->st_blocks  = 0;
+  
+  return ret;
+}
+
+/****************************************************************************
+ * Public Functions
+ ****************************************************************************/
+
+#endif /* CONFIG_FS_PROCFS && !CONFIG_FS_PROCFS_EXCLUDE_SMARTFS */