PM update; NSH extension to catch return values

git-svn-id: https://nuttx.svn.sourceforge.net/svnroot/nuttx/trunk@4987 7fd9a85b-ad96-42d3-883c-3090e2eb8679

3 files changed, 74 insertions, 17 deletions

diff --git a/apps/ChangeLog.txt b/apps/ChangeLog.txt
index 9edc37c4e7..ee7b8f26a5 100755
--- a/apps/ChangeLog.txt
+++ b/apps/ChangeLog.txt
@@ -259,3 +259,5 @@
 	* apps/modbus:  Add CONFIG_MB_TERMIOS.  If the driver doesn't support
 	  termios ioctls, then don't bother trying to configure the baud, parity
 	  etc.
+	* apps/nslib:  If waitpid() is supported, then NSH not catches the
+	  return value from spawned applications.
diff --git a/apps/nshlib/nsh_apps.c b/apps/nshlib/nsh_apps.c
index c6f7509489..eb019f57b2 100644
--- a/apps/nshlib/nsh_apps.c
+++ b/apps/nshlib/nsh_apps.c
@@ -84,7 +84,22 @@
  ****************************************************************************/
 
 /****************************************************************************
- * Name: nsh_execute
+ * Name: nsh_execapp
+ *
+ * Description:
+ *    Attempt to execute the application task whose name is 'cmd'
+ *
+ * Returned Value:
+ *   -1 (ERRROR) 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_execapp(FAR struct nsh_vtbl_s *vtbl, FAR const char *cmd,
@@ -103,7 +118,21 @@ int nsh_execapp(FAR struct nsh_vtbl_s *vtbl, FAR const char *cmd,
 #ifdef CONFIG_SCHED_WAITPID
   if (vtbl->np.np_bg == false)
     {
-      waitpid(ret, NULL, 0);
+      int rc = 0;
+
+      waitpid(ret, &rc, 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.
+       */
     }
   else
 #endif
@@ -111,11 +140,15 @@ int nsh_execapp(FAR struct nsh_vtbl_s *vtbl, FAR const char *cmd,
       struct sched_param param;
       sched_getparam(0, &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;
     }
 
-  return OK;
+  return ret;
 }
 
 #endif /* CONFIG_NSH_BUILTIN_APPS */
-
-
diff --git a/apps/nshlib/nsh_parse.c b/apps/nshlib/nsh_parse.c
index 76cd4664ee..64850eb628 100644
--- a/apps/nshlib/nsh_parse.c
+++ b/apps/nshlib/nsh_parse.c
@@ -67,7 +67,7 @@
 #include "nsh_console.h"
 
 /****************************************************************************
- * Definitions
+ * Pre-processor Definitions
  ****************************************************************************/
 
 /* Argument list size
@@ -487,6 +487,16 @@ static int cmd_exit(FAR struct nsh_vtbl_s *vtbl, int argc, char **argv)
 
 /****************************************************************************
  * Name: nsh_execute
+ *
+ * Description:
+ *   Exectue the command in argv[0]
+ *
+ * Returned Value:
+ *   -1 (ERRROR) if the command was unsuccessful
+ *    0 (OK)     if the command was successful
+ *    1          if an application task was spawned successfully, but
+ *               returned failure exit status.
+ *
  ****************************************************************************/
 
 static int nsh_execute(FAR struct nsh_vtbl_s *vtbl, int argc, char *argv[])
@@ -506,18 +516,20 @@ static int nsh_execute(FAR struct nsh_vtbl_s *vtbl, int argc, char *argv[])
 
    cmd = argv[0];
    
-   /* Try to find a command in the application library.
-    */
+   /* Try to find a command in the application library. */
 
 #ifdef CONFIG_NSH_BUILTIN_APPS
-   if (nsh_execapp(vtbl, cmd, argv) == OK)
-     {
-       /* The pre-built application was successfully started -- return OK. */
+   ret = nsh_execapp(vtbl, cmd, argv);
 
-       return OK;
-     }
-#endif
+   /* The pre-built application was successfully started -- return OK 
+    * or 1 if it returned a non-zero exit status.
+    */
 
+   if (ret >= 0)
+    {
+      return ret;
+    }
+#endif
 
    /* See if the command is one that we understand */
 
@@ -1123,6 +1135,7 @@ int nsh_parse(FAR struct nsh_vtbl_s *vtbl, char *cmdline)
           break;
         }
     }
+
   argv[argc] = NULL;
 
   /* Check if the command should run in background */
@@ -1136,7 +1149,6 @@ int nsh_parse(FAR struct nsh_vtbl_s *vtbl, char *cmdline)
     }
 #endif
 
-
   /* Check if the output was re-directed using > or >> */
 
   if (argc > 2)
@@ -1285,6 +1297,7 @@ int nsh_parse(FAR struct nsh_vtbl_s *vtbl, char *cmdline)
           nsh_release(bkgvtbl);
           goto errout;
         }
+
       nsh_output(vtbl, "%s [%d:%d]\n", cmd, thread, param.sched_priority);
     }
   else
@@ -1300,7 +1313,12 @@ int nsh_parse(FAR struct nsh_vtbl_s *vtbl, char *cmdline)
         }
 
       /* Then execute the command in "foreground" -- i.e., while the user waits
-       * for the next prompt.
+       * for the next prompt.  nsh_execute will return:
+       *
+       * -1 (ERRROR) if the command was unsuccessful
+       *  0 (OK)     if the command was successful
+       *  1          if an application task was spawned successfully, but
+       *             returned failure exit status.
        */
 
       ret = nsh_execute(vtbl, argc, argv);
@@ -1314,7 +1332,11 @@ int nsh_parse(FAR struct nsh_vtbl_s *vtbl, char *cmdline)
           nsh_undirect(vtbl, save);
         }
 
-      if (ret < 0)
+      /* Treat both errors and non-zero return codes as "errors" so that
+       * it is possible to test for non-zero returns in nsh scripts.
+       */
+
+      if (ret != OK)
         {
           goto errout;
         }