Add pipeline support for nsh commandline

builtin/exec_builtin.c

@@ -45,13 +45,7 @@
  * Input Parameter:
  *   filename      - Name of the linked-in binary to be started.
  *   argv          - Argument list
- *   redirfile_in  - If input is redirected, this parameter will be non-NULL
- *                   and will provide the full path to the file.
- *   redirfile_out - If output is redirected, this parameter will be non-NULL
- *                   and will provide the full path to the file.
- *   oflags        - If output is redirected, this parameter will provide the
- *                   open flags to use.  This will support file replacement
- *                   of appending to an existing file.
+ *   param         - Parameters for execute.
  *
  * Returned Value:
  *   This is an end-user function, so it follows the normal convention:
@@ -61,13 +55,12 @@
  ****************************************************************************/
 
 int exec_builtin(FAR const char *appname, FAR char * const *argv,
-                 FAR const char *redirfile_in, FAR const char *redirfile_out,
-                 int oflags)
+                 FAR const struct nsh_param_s *param)
 {
   FAR const struct builtin_s *builtin;
   posix_spawnattr_t attr;
   posix_spawn_file_actions_t file_actions;
-  struct sched_param param;
+  struct sched_param sched;
   pid_t pid;
   int index;
   int ret;
@@ -106,8 +99,8 @@ int exec_builtin(FAR const char *appname, FAR char * const *argv,
 
   /* Set the correct task size and priority */
 
-  param.sched_priority = builtin->priority;
-  ret = posix_spawnattr_setschedparam(&attr, &param);
+  sched.sched_priority = builtin->priority;
+  ret = posix_spawnattr_setschedparam(&attr, &sched);
   if (ret != 0)
     {
       goto errout_with_actions;
@@ -147,34 +140,67 @@ int exec_builtin(FAR const char *appname, FAR char * const *argv,
 
 #endif
 
-  /* Is input being redirected? */
-
-  if (redirfile_in)
+  if (param)
     {
-      /* Set up to close open redirfile and set to stdin (0) */
+      /* Is input being redirected? */
 
-      ret = posix_spawn_file_actions_addopen(&file_actions, 0,
-                                             redirfile_in, O_RDONLY, 0);
-      if (ret != 0)
+      if (param->file_in)
         {
-          serr("ERROR: posix_spawn_file_actions_addopen failed: %d\n", ret);
-          goto errout_with_actions;
+          /* Set up to close open redirfile and set to stdin (0) */
+
+          ret = posix_spawn_file_actions_addopen(&file_actions, 0,
+                                                 param->file_in,
+                                                 param->oflags_in, 0);
+          if (ret != 0)
+            {
+              serr("ERROR: posix_spawn_file_actions_addopen failed: %d\n",
+                   ret);
+              goto errout_with_actions;
+            }
         }
-    }
-
-  /* Is output being redirected? */
+#ifdef CONFIG_NSH_PIPELINE
+      else if (param->fd_in != -1)
+        {
+          ret = posix_spawn_file_actions_adddup2(&file_actions,
+                                                 param->fd_in, 0);
+          if (ret != 0)
+            {
+              serr("ERROR: posix_spawn_file_actions_adddup2 failed: %d\n",
+                   ret);
+              goto errout_with_actions;
+            }
+        }
+#endif
 
-  if (redirfile_out)
-    {
-      /* Set up to close open redirfile and set to stdout (1) */
+      /* Is output being redirected? */
 
-      ret = posix_spawn_file_actions_addopen(&file_actions, 1,
-                                             redirfile_out, oflags, 0644);
-      if (ret != 0)
+      if (param->file_out)
         {
-          serr("ERROR: posix_spawn_file_actions_addopen failed: %d\n", ret);
-          goto errout_with_actions;
+          /* Set up to close open redirfile and set to stdout (1) */
+
+          ret = posix_spawn_file_actions_addopen(&file_actions, 1,
+                                                 param->file_out,
+                                                 param->oflags_out, 0644);
+          if (ret != 0)
+            {
+              serr("ERROR: posix_spawn_file_actions_addopen failed: %d\n",
+                   ret);
+              goto errout_with_actions;
+            }
         }
+#ifdef CONFIG_NSH_PIPELINE
+      else if (param->fd_out != -1)
+        {
+          ret = posix_spawn_file_actions_adddup2(&file_actions,
+                                                 param->fd_out, 1);
+          if (ret != 0)
+            {
+              serr("ERROR: posix_spawn_file_actions_adddup2 failed: %d\n",
+                   ret);
+              goto errout_with_actions;
+            }
+        }
+#endif
     }
 
 #ifdef CONFIG_LIBC_EXECFUNCS

include/builtin/builtin.h

@@ -30,6 +30,7 @@
 #include <sys/types.h>
 
 #include <nuttx/lib/builtin.h>
+#include <nshlib/nshlib.h>
 
 /****************************************************************************
  * Pre-processor Definitions
@@ -66,13 +67,7 @@ extern "C"
  * Input Parameter:
  *   filename      - Name of the linked-in binary to be started.
  *   argv          - Argument list
- *   redirfile_in  - If input is redirected, this parameter will be non-NULL
- *                   and will provide the full path to the file.
- *   redirfile_out - If output is redirected, this parameter will be non-NULL
- *                   and will provide the full path to the file.
- *   oflags        - If output is redirected, this parameter will provide the
- *                   open flags to use.  This will support file replacement
- *                   of appending to an existing file.
+ *   param         - Parameters for execute.
  *
  * Returned Value:
  *   This is an end-user function, so it follows the normal convention:
@@ -82,8 +77,7 @@ extern "C"
  ****************************************************************************/
 
 int exec_builtin(FAR const char *appname, FAR char * const *argv,
-                 FAR const char *redirfile_in, FAR const char *redirfile_out,
-                 int oflags);
+                 FAR const struct nsh_param_s *param);
 
 #undef EXTERN
 #if defined(__cplusplus)

include/nshlib/nshlib.h

@@ -65,6 +65,25 @@
 #  define SCHED_NSH SCHED_FIFO
 #endif
 
+struct nsh_param_s
+{
+  /* Redirect input/output through `fd` OR `path_name`
+   *
+   * Select one:
+   * 1. Using fd_in/fd_out as oldfd for dup2() if greater than -1.
+   * 2. Using file_in/file_out as full path to the file if it is
+   *    not NULL, and oflags_in/oflags_out as flags for open().
+   */
+
+  int fd_in;
+  int fd_out;
+
+  int oflags_in;
+  int oflags_out;
+  FAR const char *file_in;
+  FAR const char *file_out;
+};
+
 /****************************************************************************
  * Public Data
  ****************************************************************************/

nshlib/Kconfig

@@ -231,6 +231,13 @@ config NSH_ALIAS_MAX_AMOUNT
 
 endif # NSH_ALIAS
 
+config NSH_PIPELINE
+	bool "Enable pipeline support"
+	default !DEFAULT_SMALL
+	depends on PIPES
+	---help---
+		Enable pipeline support for nsh.
+
 endmenu # Command Line Configuration
 
 config NSH_BUILTIN_APPS

nshlib/nsh.h

@@ -39,6 +39,7 @@
 #endif
 
 #include <nuttx/usb/usbdev_trace.h>
+#include <nshlib/nshlib.h>
 
 /****************************************************************************
  * Pre-processor Definitions
@@ -858,14 +859,12 @@ int nsh_command(FAR struct nsh_vtbl_s *vtbl, int argc, FAR char *argv[]);
 
 #ifdef CONFIG_NSH_BUILTIN_APPS
 int nsh_builtin(FAR struct nsh_vtbl_s *vtbl, FAR const char *cmd,
-                FAR char **argv, FAR const char *redirfile_in,
-                FAR const char *redirfile_out, int oflags);
+                FAR char **argv, FAR const struct nsh_param_s *param);
 #endif
 
 #ifdef CONFIG_NSH_FILE_APPS
 int nsh_fileapp(FAR struct nsh_vtbl_s *vtbl, FAR const char *cmd,
-                FAR char **argv, FAR const char *redirfile_in,
-                FAR const char *redirfile_out, int oflags);
+                FAR char **argv, FAR const struct nsh_param_s *param);
 #endif
 
 #ifndef CONFIG_DISABLE_ENVIRON

nshlib/nsh_builtin.c

@@ -69,8 +69,8 @@
  ****************************************************************************/
 
 int nsh_builtin(FAR struct nsh_vtbl_s *vtbl, FAR const char *cmd,
-                FAR char **argv, FAR const char *redirfile_in,
-                FAR const char *redirfile_out, int oflags)
+                FAR char **argv,
+                FAR const struct nsh_param_s *param)
 {
 #if !defined(CONFIG_NSH_DISABLEBG) && defined(CONFIG_SCHED_CHILD_STATUS)
   struct sigaction act;
@@ -102,7 +102,7 @@ int nsh_builtin(FAR struct nsh_vtbl_s *vtbl, FAR const char *cmd,
    * applications.
    */
 
-  ret = exec_builtin(cmd, argv, redirfile_in, redirfile_out, oflags);
+  ret = exec_builtin(cmd, argv, param);
   if (ret >= 0)
     {
       /* The application was successfully started with pre-emption disabled.
@@ -234,9 +234,9 @@ int nsh_builtin(FAR struct nsh_vtbl_s *vtbl, FAR const char *cmd,
 
           sigaction(SIGCHLD, &old, NULL);
 #  endif
-          struct sched_param param;
-          sched_getparam(ret, &param);
-          nsh_output(vtbl, "%s [%d:%d]\n", cmd, ret, param.sched_priority);
+          struct sched_param sched;
+          sched_getparam(ret, &sched);
+          nsh_output(vtbl, "%s [%d:%d]\n", cmd, ret, sched.sched_priority);
 
           /* Backgrounded commands always 'succeed' as long as we can start
            * them.