nsh: return EOF when nread is 0

If enable CONFIG NSH_CLE. When sh reads data and detects that nread is 0,
return EOF and exit.

Signed-off-by: yangsong8 <[email protected]>

Author: yangsong8-a1

nshlib/nsh_session.c

@@ -211,11 +211,12 @@ int nsh_session(FAR struct console_stdio_s *pstate,
 
       ret = cle_fd(pstate->cn_line, nsh_prompt(), LINE_MAX,
                    INFD(pstate), OUTFD(pstate));
-      if (ret < 0)
+      if (ret == EOF)
         {
           dprintf(ERRFD(pstate), g_fmtcmdfailed, "nsh_session",
                   "cle", NSH_ERRNO_OF(-ret));
-          continue;
+          ret = EXIT_SUCCESS;
+          break;
         }
 #else
       /* Display the prompt string */

system/cle/cle.c

@@ -316,7 +316,7 @@ static int cle_getch(FAR struct cle_s *priv)
           if (nread == 0 || errcode != EINTR)
             {
               cledbg("ERROR: read from stdin failed: %d\n", errcode);
-              return -EIO;
+              return EOF;
             }
         }
     }
@@ -703,9 +703,9 @@ static int cle_editloop(FAR struct cle_s *priv)
       for (; ; )
         {
           ch = cle_getch(priv);
-          if (ch < 0)
+          if (ch == EOF)
             {
-              return -EIO;
+              return EOF;
             }
           else if (state != 0)
             {