If we are using a USB serial console, then NSH must wait for the USB device to be connected

git-svn-id: svn://svn.code.sf.net/p/nuttx/code/trunk@4327 42af7a65-404d-4744-a932-0658087f49c3
2025-10-19 11:23:07 +08:00 · 2012-01-24 00:00:31 +00:00
parent a3301a7079
commit c2266ac99a
6 changed files with 237 additions and 55 deletions
--- a/nshlib/nsh_usbdev.c
+++ b/nshlib/nsh_usbdev.c
@@ -0,0 +1,149 @@
+/****************************************************************************
+ * apps/nshlib/nsh_usbdev.c
+ *
+ *   Copyright (C) 2012 Gregory Nutt. All rights reserved.
+ *   Author: Gregory Nutt <gnutt@nuttx.org>
+ *
+ * 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 <stdlib.h>
+
+#include "nsh.h"
+
+#ifdef CONFIG_USBDEV
+
+/****************************************************************************
+ * Definitions
+ ****************************************************************************/
+
+/****************************************************************************
+ * Private Types
+ ****************************************************************************/
+
+/****************************************************************************
+ * Private Function Prototypes
+ ****************************************************************************/
+
+/****************************************************************************
+ * Private Data
+ ****************************************************************************/
+
+/****************************************************************************
+ * Public Data
+ ****************************************************************************/
+
+/****************************************************************************
+ * Private Functions
+ ****************************************************************************/
+
+/****************************************************************************
+ * Public Functions
+ ****************************************************************************/
+
+/****************************************************************************
+ * Name: nsh_usbconsole
+ ****************************************************************************/
+
+#ifdef HAVE_USB_CONSOLE
+int nsh_usbconsole(void)
+{
+  int errval;
+  int fd;
+
+  /* Don't start the NSH console until the console device is ready.  Chances
+   * are, we get here with no functional console.  The USB console will not
+   * be available until the device is connected to the host and until the
+   * host-side application opens the connection.
+   */
+
+  /* Make sure the stdin, stdout, and stderr are closed */
+
+  (void)fclose(stdin);
+  (void)fclose(stdout);
+  (void)fclose(stderr);
+
+  /* Open the USB serial device for writing */
+
+  do
+    {
+      /* Try to open the console */
+
+      fd = open("/dev/console", O_RDWR);
+      if (fd < 0)
+        {
+          /* ENOTCONN means that the USB device is not yet connected. Anything
+           * else is bad.
+           */
+
+          DEBUGASSERT(errno == ENOTCONN);
+
+          /* Sleep a bit and try again */
+
+          sleep(2);
+        }
+    }
+  while (fd < 0);
+
+  /* Dup the fd to create standard fd 0-2 */
+
+  (void)dup2(fd, 0);
+  (void)dup2(fd, 1);
+  (void)dup2(fd, 2);
+
+  /* We can close the original file descriptor now (unless it was one of 0-2) */
+
+  if (fd > 2)
+    {
+      close(fd);
+    }
+
+  /* fdopen to get the stdin, stdout and stderr streams. The following logic depends
+   * on the fact that the library* layer will allocate FILEs in order.  And since
+   * we closed stdin, stdout, and stderr above, that is what we should get.
+   *
+   * fd = 0 is stdin  (read-only)
+   * fd = 1 is stdout (write-only, append)
+   * fd = 2 is stderr (write-only, append)
+   */
+
+  (void)fdopen(0, "r");
+  (void)fdopen(1, "a");
+  (void)fdopen(2, "a");
+  return OK;
+}
+
+#endif /* HAVE_USB_CONSOLE */
+#endif /* CONFIG_USBDEV */