Implement redirection of output from NSH builtin commands to a file in a mounted volume

git-svn-id: svn://svn.code.sf.net/p/nuttx/code/trunk@5521 42af7a65-404d-4744-a932-0658087f49c3

1 files changed, 226 insertions, 0 deletions

diff --git a/apps/nshlib/nsh_builtin.c b/apps/nshlib/nsh_builtin.c
new file mode 100644
index 000000000..16e3e9427
--- /dev/null
+++ b/apps/nshlib/nsh_builtin.c
@@ -0,0 +1,226 @@
+/****************************************************************************
+ * apps/nshlib/nsh_builtin.c
+ *
+ * Originally by:
+ *
+ *   Copyright (C) 2011 Uros Platise. All rights reserved.
+ *   Author: Uros Platise <uros.platise@isotel.eu>
+ *
+ * With subsequent updates, modifications, and general maintenance by:
+ *
+ *   Copyright (C) 2011-2013 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>
+
+#ifdef CONFIG_SCHED_WAITPID
+#  include <sys/wait.h>
+#endif
+
+#include <stdbool.h>
+#include <errno.h>
+#include <string.h>
+
+#include <apps/apps.h>
+
+#include "nsh.h"
+#include "nsh_console.h"
+
+#ifdef CONFIG_NSH_BUILTIN_APPS
+
+/****************************************************************************
+ * Definitions
+ ****************************************************************************/
+
+/****************************************************************************
+ * Private Types
+ ****************************************************************************/
+
+/****************************************************************************
+ * Private Function Prototypes
+ ****************************************************************************/
+
+/****************************************************************************
+ * Private Data
+ ****************************************************************************/
+
+/****************************************************************************
+ * Public Data
+ ****************************************************************************/
+
+/****************************************************************************
+ * Private Functions
+ ****************************************************************************/
+
+/****************************************************************************
+ * Public Functions
+ ****************************************************************************/
+
+/****************************************************************************
+ * Name: nsh_builtin
+ *
+ * Description:
+ *    Attempt to execute the application task whose name is 'cmd'
+ *
+ * Returned Value:
+ *   <0          If exec_builtin() fails, then the negated errno value
+ *               is returned.
+ *   -1 (ERROR)  if the application task corresponding to 'cmd' could not
+ *               be started (possibly because it doesn not exist).
+ *    0 (OK)     if the application task corresponding to 'cmd' was
+ *               and successfully started.  If CONFIG_SCHED_WAITPID is
+ *               defined, this return value also indicates that the
+ *               application returned successful status (EXIT_SUCCESS)
+ *    1          If CONFIG_SCHED_WAITPID is defined, then this return value
+ *               indicates that the application task was spawned successfully
+ *               but returned failure exit status.
+ *
+ ****************************************************************************/
+
+int nsh_builtin(FAR struct nsh_vtbl_s *vtbl, FAR const char *cmd,
+                FAR char **argv, FAR const char *redirfile, int oflags)
+{
+  int ret = OK;
+
+  /* Lock the scheduler to prevent the application from running until the
+   * waitpid() has been called.
+   */
+
+  sched_lock();
+
+  /* Try to find and execute the command within the list of builtin
+   * applications.
+   */
+
+  ret = exec_builtin(cmd, (FAR const char **)argv, redirfile, oflags);
+  if (ret >= 0)
+    {
+      /* The application was successfully started (but still blocked because
+       * the scheduler is locked).  If the application was not backgrounded,
+       * then we need to wait here for the application to exit.  These really
+       * only works works with the following options:
+       *
+       * - CONFIG_NSH_DISABLEBG - Do not run commands in background
+       * - CONFIG_SCHED_WAITPID - Required to run external commands in
+       *     foreground
+       *
+       * These concepts do not apply cleanly to the external applications.
+       */
+
+#ifdef CONFIG_SCHED_WAITPID
+
+      /* CONFIG_SCHED_WAITPID is selected, so we may run the command in
+       * foreground unless we were specifically requested to run the command
+       * in background (and running commands in background is enabled).
+       */
+
+#  ifndef CONFIG_NSH_DISABLEBG
+      if (vtbl->np.np_bg == false)
+#  endif /* CONFIG_NSH_DISABLEBG */
+        {
+          int rc = 0;
+
+          /* Wait for the application to exit.  Since we have locked the
+           * scheduler above, we know that the application has not yet
+           * started and there is no possibility that it has already exited.
+           * The scheduler will be unlocked while waitpid is waiting and the
+           * application will be able to run.
+           */
+
+          ret = waitpid(ret, &rc, 0);
+          if (ret >= 0)
+            {
+              /* We can't return the exact status (nsh has nowhere to put it)
+               * so just pass back zero/nonzero in a fashion that doesn't look 
+               * like an error.
+               */
+
+              ret = (rc == 0) ? OK : 1;
+
+             /* TODO:  Set the environment variable '?' to a string corresponding
+              * to WEXITSTATUS(rc) so that $? will expand to the exit status of
+              * the most recently executed task.
+              */
+            }
+        }
+#  ifndef CONFIG_NSH_DISABLEBG
+      else
+#  endif /* CONFIG_NSH_DISABLEBG */
+#endif /* CONFIG_SCHED_WAITPID */
+
+      /* We get here if either:
+       *
+       * - CONFIG_SCHED_WAITPID is not selected meaning that all commands
+       *   have to be run in background, or
+       * - CONFIG_SCHED_WAITPID and CONFIG_NSH_DISABLEBG are both selected, but the
+       *   user requested to run the command in background.
+       *
+       * NOTE that the case of a) CONFIG_SCHED_WAITPID is not selected and
+       * b) CONFIG_NSH_DISABLEBG selected cannot be supported.  In that event, all
+       * commands will have to run in background.  The waitpid() API must be
+       * available to support running the command in foreground.
+       */
+
+#if !defined(CONFIG_SCHED_WAITPID) || !defined(CONFIG_NSH_DISABLEBG)
+        {
+          struct sched_param param;
+          sched_getparam(ret, &param);
+          nsh_output(vtbl, "%s [%d:%d]\n", cmd, ret, param.sched_priority);
+
+          /* Backgrounded commands always 'succeed' as long as we can start
+           * them.
+           */
+
+          ret = OK;
+        }
+#endif /* !CONFIG_SCHED_WAITPID || !CONFIG_NSH_DISABLEBG */
+    }
+
+  sched_unlock();
+
+  /* If exec_builtin() or waitpid() failed, then return -1 (ERROR) with the
+   * errno value set appropriately.
+   */
+
+  if (ret < 0)
+    {
+      return ERROR;
+    }
+
+  return ret;
+}
+
+#endif /* CONFIG_NSH_BUILTIN_APPS */