modify nuttx bug of lack of files

2021-06-11 11:25:07 +08:00
parent 4a7f51a5e9
commit 6d0f2ca39a
6752 changed files with 1528133 additions and 0 deletions
@@ -0,0 +1,124 @@
+/****************************************************************************
+ * drivers/dev_null.c
+ *
+ * Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements.  See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.  The
+ * ASF licenses this file to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance with the
+ * License.  You may obtain a copy of the License at
+ *
+ *   http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+ * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.  See the
+ * License for the specific language governing permissions and limitations
+ * under the License.
+ *
+ ****************************************************************************/
+
+/****************************************************************************
+ * Included Files
+ ****************************************************************************/
+
+#include <nuttx/config.h>
+
+#include <sys/types.h>
+#include <stdbool.h>
+#include <string.h>
+#include <poll.h>
+#include <errno.h>
+
+#include <nuttx/semaphore.h>
+#include <nuttx/fs/fs.h>
+#include <nuttx/drivers/drivers.h>
+
+/****************************************************************************
+ * Private Function Prototypes
+ ****************************************************************************/
+
+static ssize_t devnull_read(FAR struct file *filep, FAR char *buffer,
+                 size_t buflen);
+static ssize_t devnull_write(FAR struct file *filep, FAR const char *buffer,
+                 size_t buflen);
+static int     devnull_poll(FAR struct file *filep, FAR struct pollfd *fds,
+                 bool setup);
+
+/****************************************************************************
+ * Private Data
+ ****************************************************************************/
+
+static const struct file_operations devnull_fops =
+{
+  NULL,          /* open */
+  NULL,          /* close */
+  devnull_read,  /* read */
+  devnull_write, /* write */
+  NULL,          /* seek */
+  NULL,          /* ioctl */
+  devnull_poll   /* poll */
+#ifndef CONFIG_DISABLE_PSEUDOFS_OPERATIONS
+  , NULL         /* unlink */
+#endif
+};
+
+/****************************************************************************
+ * Private Functions
+ ****************************************************************************/
+
+/****************************************************************************
+ * Name: devnull_read
+ ****************************************************************************/
+
+static ssize_t devnull_read(FAR struct file *filep, FAR char *buffer,
+                            size_t len)
+{
+  return 0; /* Return EOF */
+}
+
+/****************************************************************************
+ * Name: devnull_write
+ ****************************************************************************/
+
+static ssize_t devnull_write(FAR struct file *filep, FAR const char *buffer,
+                             size_t len)
+{
+  return len; /* Say that everything was written */
+}
+
+/****************************************************************************
+ * Name: devnull_poll
+ ****************************************************************************/
+
+static int devnull_poll(FAR struct file *filep, FAR struct pollfd *fds,
+                        bool setup)
+{
+  if (setup)
+    {
+      fds->revents |= (fds->events & (POLLIN | POLLOUT));
+      if (fds->revents != 0)
+        {
+          nxsem_post(fds->sem);
+        }
+    }
+
+  return OK;
+}
+
+/****************************************************************************
+ * Public Functions
+ ****************************************************************************/
+
+/****************************************************************************
+ * Name: devnull_register
+ *
+ * Description:
+ *   Register /dev/null
+ *
+ ****************************************************************************/
+
+void devnull_register(void)
+{
+  register_driver("/dev/null", &devnull_fops, 0666, NULL);
+}