fs: Reimplement file_open to not depend on nx_open

on the other hand, open/nx_open call file_open instead

Signed-off-by: Xiang Xiao <[email protected]>
Change-Id: I66990a77cdeb6ff18f7bf48a65bbc7b701dad552

fs/driver/driver.h

@@ -119,7 +119,7 @@ int find_blockdriver(FAR const char *pathname, int mountflags,
  ****************************************************************************/
 
 #if !defined(CONFIG_DISABLE_MOUNTPOINT)
-int block_proxy(FAR const char *blkdev, int oflags);
+int block_proxy(FAR struct file *filep, FAR const char *blkdev, int oflags);
 #endif
 
 /****************************************************************************

fs/driver/fs_blockproxy.c

@@ -105,10 +105,10 @@ static FAR char *unique_chardev(void)
 
       /* Make sure that file name is not in use */
 
-      ret = stat(devbuf, &statbuf);
+      ret = nx_stat(devbuf, &statbuf, 1);
       if (ret < 0)
         {
-          DEBUGASSERT(errno == ENOENT);
+          DEBUGASSERT(ret == -ENOENT);
           return strdup(devbuf);
         }
 
@@ -147,12 +147,11 @@ static FAR char *unique_chardev(void)
  *
  ****************************************************************************/
 
-int block_proxy(FAR const char *blkdev, int oflags)
+int block_proxy(FAR struct file *filep, FAR const char *blkdev, int oflags)
 {
   FAR char *chardev;
   bool readonly;
   int ret;
-  int fd;
 
   DEBUGASSERT(blkdev);
 
@@ -183,10 +182,9 @@ int block_proxy(FAR const char *blkdev, int oflags)
   /* Open the newly created character driver */
 
   oflags &= ~(O_CREAT | O_EXCL | O_APPEND | O_TRUNC);
-  fd = nx_open(chardev, oflags);
-  if (fd < 0)
+  ret = file_open(filep, chardev, oflags);
+  if (ret < 0)
     {
-      ret = fd;
       ferr("ERROR: Failed to open %s: %d\n", chardev, ret);
       goto errout_with_bchdev;
     }
@@ -209,7 +207,7 @@ int block_proxy(FAR const char *blkdev, int oflags)
    */
 
   kmm_free(chardev);
-  return fd;
+  return OK;
 
 errout_with_bchdev:
   unlink(chardev);

fs/inode/Make.defs

@@ -36,7 +36,7 @@
 CSRCS += fs_files.c fs_foreachinode.c fs_inode.c fs_inodeaddref.c
 CSRCS += fs_inodebasename.c fs_inodefind.c fs_inodefree.c fs_inoderelease.c
 CSRCS += fs_inoderemove.c fs_inodereserve.c fs_inodesearch.c
-CSRCS += fs_fileopen.c fs_filedetach.c
+CSRCS += fs_filedetach.c
 
 # Include inode/utils build support
 

fs/vfs/fs_open.c

@@ -80,31 +80,30 @@ int inode_checkflags(FAR struct inode *inode, int oflags)
 }
 
 /****************************************************************************
- * Name: nx_vopen
+ * Name: file_vopen
  *
  * Description:
- *   nx_vopen() is identical to 'nx_open' except that it accepts a va_list
+ *   file_vopen() is identical to 'file_open' except that it accepts va_list
  *   as an argument versus taking a variable length list of arguments.
  *
- *   nx_vopen() is an internal NuttX interface and should not be called from
- *   applications.
+ *   file_vopen() is an internal NuttX interface and should not be called
+ *   from applications.
  *
  * Returned Value:
- *   The new file descriptor is returned on success; a negated errno value is
- *   returned on any failure.
+ *   Zero (OK) is returned on success.  On failure, a negated errno value is
+ *   returned.
  *
  ****************************************************************************/
 
-int nx_vopen(FAR const char *path, int oflags, va_list ap)
+int file_vopen(FAR struct file *filep,
+               FAR const char *path, int oflags, va_list ap)
 {
   struct inode_search_s desc;
-  FAR struct file *filep;
   FAR struct inode *inode;
 #if defined(CONFIG_FILE_MODE) || !defined(CONFIG_DISABLE_MOUNTPOINT)
   mode_t mode = 0666;
 #endif
   int ret;
-  int fd;
 
   if (path == NULL)
     {
@@ -160,20 +159,11 @@ int nx_vopen(FAR const char *path, int oflags, va_list ap)
       /* Release the inode reference */
 
       inode_release(inode);
+      RELEASE_SEARCH(&desc);
 
       /* Get the file descriptor of the opened character driver proxy */
 
-      fd = block_proxy(path, oflags);
-      if (fd < 0)
-        {
-          ret = fd;
-          goto errout_with_search;
-        }
-
-      /* Return the file descriptor */
-
-      RELEASE_SEARCH(&desc);
-      return fd;
+      return block_proxy(filep, path, oflags);
     }
   else
 #endif
@@ -204,20 +194,10 @@ int nx_vopen(FAR const char *path, int oflags, va_list ap)
 
   /* Associate the inode with a file structure */
 
-  fd = files_allocate(inode, oflags, 0, NULL, 0);
-  if (fd < 0)
-    {
-      ret = fd;
-      goto errout_with_inode;
-    }
-
-  /* Get the file structure corresponding to the file descriptor. */
-
-  ret = fs_getfilep(fd, &filep);
-  if (ret < 0)
-    {
-      goto errout_with_inode;
-    }
+  filep->f_oflags = oflags;
+  filep->f_pos    = 0;
+  filep->f_inode  = inode;
+  filep->f_priv   = NULL;
 
   /* Perform the driver open operation.  NOTE that the open method may be
    * called many times.  The driver/mountpoint logic should handled this
@@ -241,23 +221,97 @@ int nx_vopen(FAR const char *path, int oflags, va_list ap)
 
   if (ret < 0)
     {
-      goto errout_with_fd;
+      goto errout_with_inode;
     }
 
   RELEASE_SEARCH(&desc);
-  return fd;
-
-errout_with_fd:
-  files_release(fd);
+  return OK;
 
 errout_with_inode:
+  filep->f_inode = NULL;
   inode_release(inode);
 
 errout_with_search:
   RELEASE_SEARCH(&desc);
   return ret;
 }
 
+/****************************************************************************
+ * Name: file_open
+ *
+ * Description:
+ *   file_open() is similar to the standard 'open' interface except that it
+ *   returns an instance of 'struct file' rather than a file descriptor.  It
+ *   also is not a cancellation point and does not modify the errno variable.
+ *
+ * Input Parameters:
+ *   filep  - The caller provided location in which to return the 'struct
+ *            file' instance.
+ *   path   - The full path to the file to be open.
+ *   oflags - open flags
+ *   ...    - Variable number of arguments, may include 'mode_t mode'
+ *
+ * Returned Value:
+ *   Zero (OK) is returned on success.  On failure, a negated errno value is
+ *   returned.
+ *
+ ****************************************************************************/
+
+int file_open(FAR struct file *filep, FAR const char *path, int oflags, ...)
+{
+  va_list ap;
+  int ret;
+
+  va_start(ap, oflags);
+  ret = file_vopen(filep, path, oflags, ap);
+  va_end(ap);
+
+  return ret;
+}
+
+/****************************************************************************
+ * Name: nx_vopen
+ *
+ * Description:
+ *   nx_vopen() is identical to 'nx_open' except that it accepts a va_list
+ *   as an argument versus taking a variable length list of arguments.
+ *
+ *   nx_vopen() is an internal NuttX interface and should not be called from
+ *   applications.
+ *
+ * Returned Value:
+ *   The new file descriptor is returned on success; a negated errno value is
+ *   returned on any failure.
+ *
+ ****************************************************************************/
+
+int nx_vopen(FAR const char *path, int oflags, va_list ap)
+{
+  struct file filep;
+  int ret;
+  int fd;
+
+  /* Let file_vopen() do all of the work */
+
+  ret = file_vopen(&filep, path, oflags, ap);
+  if (ret < 0)
+    {
+      return ret;
+    }
+
+  /* Allocate a new file descriptor for the inode */
+
+  fd = files_allocate(filep.f_inode, filep.f_oflags,
+                      filep.f_pos, filep.f_priv, 0);
+  if (fd < 0)
+    {
+      file_close(&filep);
+      return fd;
+    }
+
+  return fd;
+}
+
 /****************************************************************************
  * Name: nx_open
  *

include/nuttx/fs/fs.h

@@ -835,6 +835,8 @@ int nx_dup2(int fd1, int fd2);
  *
  ****************************************************************************/
 
+int file_vopen(FAR struct file *filep,
+               FAR const char *path, int oflags, va_list ap);
 int file_open(FAR struct file *filep, FAR const char *path, int oflags, ...);
 
 /****************************************************************************