NSH will now run files from the file system; Add logic to unload and clean-up after running a task from a file system; Extensions to builtin apps from Mike Smith

git-svn-id: svn://svn.code.sf.net/p/nuttx/code/trunk@5529 42af7a65-404d-4744-a932-0658087f49c3

1 files changed, 298 insertions, 0 deletions

diff --git a/apps/nshlib/nsh_fileapps.c b/apps/nshlib/nsh_fileapps.c
new file mode 100644
index 000000000..7f9f58e53
--- /dev/null
+++ b/apps/nshlib/nsh_fileapps.c
@@ -0,0 +1,298 @@
+/****************************************************************************
+ * apps/nshlib/nsh_fileapps.c
+ *
+ *   Copyright (C) 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 <signal.h>
+#include <spawn.h>
+#include <errno.h>
+#include <string.h>
+
+#include "nsh.h"
+#include "nsh_console.h"
+
+#ifdef CONFIG_NSH_FILE_APPS
+
+/****************************************************************************
+ * Definitions
+ ****************************************************************************/
+
+/****************************************************************************
+ * Private Types
+ ****************************************************************************/
+
+/****************************************************************************
+ * Private Function Prototypes
+ ****************************************************************************/
+
+/****************************************************************************
+ * Private Data
+ ****************************************************************************/
+
+/****************************************************************************
+ * Public Data
+ ****************************************************************************/
+
+/****************************************************************************
+ * Private Functions
+ ****************************************************************************/
+
+/****************************************************************************
+ * Public Functions
+ ****************************************************************************/
+
+/****************************************************************************
+ * Name: nsh_fileapp
+ *
+ * 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_fileapp(FAR struct nsh_vtbl_s *vtbl, FAR const char *cmd,
+                FAR char **argv, FAR const char *redirfile, int oflags)
+{
+  posix_spawn_file_actions_t file_actions;
+  posix_spawnattr_t attr;
+  pid_t pid;
+  int ret;
+
+  /* Initialize the attributes file actions structure */
+
+  ret = posix_spawn_file_actions_init(&file_actions);
+  if (ret != 0)
+    {
+      /* posix_spawn_file_actions_init returns a positive errno value on
+       * failure.
+       */
+
+      nsh_output(vtbl, g_fmtcmdfailed, cmd, "posix_spawn_file_actions_init",
+                NSH_ERRNO_OF(ret));
+      goto errout;
+    }
+
+  ret = posix_spawnattr_init(&attr);
+  if (ret != 0)
+    {
+      /* posix_spawnattr_init returns a positive errno value on failure. */
+
+      nsh_output(vtbl, g_fmtcmdfailed, cmd, "posix_spawnattr_init",
+                 NSH_ERRNO);
+      goto errout_with_actions;
+    }
+
+  /* Handle re-direction of output */
+
+  if (redirfile)
+    {
+      ret = posix_spawn_file_actions_addopen(&file_actions, 1, redirfile,
+                                             oflags, 0644);
+      if (ret != 0)
+        {
+           /* posix_spawn_file_actions_addopen returns a positive errno
+            * value on failure.
+            */
+
+          nsh_output(vtbl, g_fmtcmdfailed, cmd,
+                     "posix_spawn_file_actions_addopen",
+                     NSH_ERRNO);
+          goto errout_with_attrs;
+        }
+    }
+
+  /* Lock the scheduler to prevent the application from running until the
+   * waitpid() has been called.
+   */
+
+  sched_lock();
+
+  /* Execute the program. posix_spawnp returns a positive errno value on
+   * failure.
+   */
+
+  ret = posix_spawnp(&pid, cmd, &file_actions, &attr, &argv[1], NULL);
+  if (ret == OK)
+    {
+      /* The application was successfully started with pre-emption disabled.
+       * In the simplest cases, the application will not have run because the
+       * the scheduler is locked.  but in the case were I/O redirected, a 
+       * proxy task ran and, as result, so may have the application.
+       *
+       * If the application did not run and if the application was not
+       * backgrounded, then we need to wait here for the application to
+       * exit.  This 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
+       */
+
+#ifdef CONFIG_SCHED_WAITPID
+      /* Check if the application is still running */
+
+      if (kill(ret, 0) < 0)
+        {
+          /* It is not running.  In this case, we have no idea if the
+           * application ran successfully or not.  Let's assume that is
+           * did.
+           */
+
+          return 0;
+        }
+
+      /* 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(pid, &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();
+
+  /* Free attibutes and file actions.  Ignoring return values in the case
+   * of an error.
+   */
+
+errout_with_actions:
+  (void)posix_spawn_file_actions_destroy(&file_actions);
+
+errout_with_attrs:
+  (void)posix_spawnattr_destroy(&attr);
+
+errout:
+  /* Most posix_spawn interfaces return a positive errno value on failure
+   * and do not set the errno variable.
+   */
+
+  if (ret > 0)
+    {
+      /* Set the errno value and return -1 */
+
+      set_errno(ret);
+      ret = ERROR;
+    }
+  else if (ret < 0)
+    {
+      /* Return -1 on failure.  errno should have been set. */
+
+      ret = ERROR;
+    }
+
+  return ret;
+}
+
+#endif /* CONFIG_NSH_FILE_APPS */