NSH now supports an MOTD string that will be presented after the greeting

ChangeLog.txt

@@ -1514,4 +1514,6 @@
 	  file like /etc/passwd (2016-01-19).
 	* apps/nshlib/nsh_passwdcmds.c:  Add useradd, userdel, and passwd
 	  commands (2019-01-20).
+	* apps/nshlib:  Now supports a Message of the Day (MOTD) that will
+	  be presented after the NSH greeting (2015-01-20).
 

nshlib/Kconfig

@@ -17,6 +17,44 @@ config NSH_LIBRARY
 
 if NSH_LIBRARY
 
+menuconfig NSH_MOTD
+	bool "Message of the Day (MOTD)"
+	default n
+	---help---
+		Support a user-provided Message of the Day (MOTD) that will be
+		presented each time new NSH session is opened.
+
+if NSH_MOTD
+
+config NSH_PLATFORM_MOTD
+	bool "Platform MOTD"
+	default n
+	---help---
+		If this option is selected, the NSH will call into platform-specific
+		logic in order to get the MOTD.  The function prototype for this
+		call is:
+
+			void platform_motd(FAR char *buffer, size_t buflen);
+
+		Where buffer is the location to return the MOTD and buflen is the
+		length of that buffer.  The maximum size of the buffer is detemined
+		by NSH_FILEIOSIZE.  An appopriate location for the
+		implementation of platform_motd would be within apps/platform/<board>.
+
+		One newline will be inserted after the platform-supplied message.
+
+config NSH_MOTD_STRING
+	string "MOTD String"
+	default "No MOTD string provided"
+	depends on !NSH_PLATFORM_MOTD
+	---help---
+		If NSH_MOTD is selected, but NSH_PLATFORM_MOTD is not, then a fixed
+		MOTD string will be used.  That string is provided by this selection.
+
+		One newline will be inserted after supplied MOTD message.
+
+endif # NSH_MOTD
+
 menu "Command Line Configuration"
 
 choice

nshlib/nsh.h

@@ -573,10 +573,12 @@
 #  undef NSH_HAVE_IOBUFFER
 #endif
 
-/* The I/O buffer is needed for the ls, cp, and ps commands */
+/* The I/O buffer is needed for the ls, cp, and ps commands.  It is also
+ * needed if the platform supplied MOTD is configured.
+ */
 
 #if defined(CONFIG_NSH_DISABLE_LS) && defined(CONFIG_NSH_DISABLE_CP) && \
-    defined(CONFIG_NSH_DISABLE_PS)
+    defined(CONFIG_NSH_DISABLE_PS) && !defined(CONFIG_NSH_PLATFORM_MOTD)
 #  undef NSH_HAVE_IOBUFFER
 #endif
 
@@ -798,6 +800,9 @@ typedef CODE int (*nsh_direntry_handler_t)(FAR struct nsh_vtbl_s *vtbl,
  ****************************************************************************/
 
 extern const char g_nshgreeting[];
+#if defined(CONFIG_NSH_MOTD) && !defined(CONFIG_NSH_PLATFORM_MOTD)
+extern const char g_nshmotd[];
+#endif
 #if defined(CONFIG_NSH_TELNET_LOGIN) && defined(CONFIG_NSH_TELNET)
 extern const char g_telnetgreeting[];
 extern const char g_userprompt[];

nshlib/nsh_parse.c

@@ -224,6 +224,12 @@ const char g_nshgreeting[]       = "\nNuttShell (NSH) NuttX-" CONFIG_VERSION_STR
 const char g_nshgreeting[]       = "\nNuttShell (NSH)\n";
 #endif
 
+/* Fixed Message of the Day (MOTD) */
+
+#if defined(CONFIG_NSH_MOTD) && !defined(CONFIG_NSH_PLATFORM_MOTD)
+const char g_nshmotd[]           = CONFIG_NSH_MOTD_STRING;
+#endif
+
 /* Telnet login prompts */
 
 #if defined(CONFIG_NSH_TELNET_LOGIN) && defined(CONFIG_NSH_TELNET)

nshlib/nsh_session.c

@@ -103,19 +103,36 @@
 
 int nsh_session(FAR struct console_stdio_s *pstate)
 {
+  FAR struct nsh_vtbl_s *vtbl;
   int ret;
 
   DEBUGASSERT(pstate);
+  vtbl = &pstate->cn_vtbl;
 
-  /* Present a greeting */
+  /* Present a greeting and possibly a Message of the Day (MOTD) */
 
   fputs(g_nshgreeting, pstate->cn_outstream);
+
+#ifdef CONFIG_NSH_MOTD
+# ifdef CONFIG_NSH_PLATFORM_MOTD
+  /* Output the platform message of the day */
+
+  platform_motd(vtbl->iobuffer, IOBUFFERSIZE);
+  fprintf(pstate->cn_outstream, "%s\n", vtbl->iobuffer);
+
+# else
+  /* Output the fixed message of the day */
+
+  fprintf(pstate->cn_outstream, "%s\n", g_nshmotd);
+# endif
+#endif
+
   fflush(pstate->cn_outstream);
 
   /* Execute the login script */
 
 #ifdef CONFIG_NSH_ROMFSRC
-  (void)nsh_loginscript(&pstate->cn_vtbl);
+  (void)nsh_loginscript(vtbl);
 #endif
 
   /* Then enter the command line parsing loop */
@@ -148,7 +165,7 @@ int nsh_session(FAR struct console_stdio_s *pstate)
         {
           /* Parse process the command */
 
-          (void)nsh_parse(&pstate->cn_vtbl, pstate->cn_line);
+          (void)nsh_parse(vtbl, pstate->cn_line);
           fflush(pstate->cn_outstream);
         }
 

nshlib/nsh_stdsession.c

@@ -102,14 +102,30 @@
 
 int nsh_session(FAR struct console_stdio_s *pstate)
 {
+  FAR struct nsh_vtbl_s *vtbl;
   int ret;
 
   DEBUGASSERT(pstate);
+  vtbl = &pstate->cn_vtbl;
 
-  /* Present a greeting */
+  /* Present a greeting and possibly a Message of the Day (MOTD) */
 
   printf("%s", g_nshgreeting);
 
+#ifdef CONFIG_NSH_MOTD
+# ifdef CONFIG_NSH_PLATFORM_MOTD
+  /* Output the platform message of the day */
+
+  platform_motd(vtbl->iobuffer, IOBUFFERSIZE);
+  printf("%s\n", vtbl->iobuffer);
+
+# else
+  /* Output the fixed message of the day */
+
+  printf("%s\n", g_nshmotd);
+# endif
+#endif
+
   /* Then enter the command line parsing loop */
 
   for (;;)
@@ -138,7 +154,7 @@ int nsh_session(FAR struct console_stdio_s *pstate)
         {
           /* Parse process the command */
 
-          (void)nsh_parse(&pstate->cn_vtbl, pstate->cn_line);
+          (void)nsh_parse(vtbl, pstate->cn_line);
         }
 
       /* Readline normally returns the number of characters read,

nshlib/nsh_telnetd.c

@@ -274,7 +274,10 @@ static int nsh_telnetlogin(FAR struct console_stdio_s *pstate)
 int nsh_telnetmain(int argc, char *argv[])
 {
   FAR struct console_stdio_s *pstate = nsh_newconsole();
+  FAR struct nsh_vtbl_s *vtbl;
+
   DEBUGASSERT(pstate != NULL);
+  vtbl = &pstate->cn_vtbl;
 
   dbg("Session [%d] Started\n", getpid());
 
@@ -283,7 +286,7 @@ int nsh_telnetmain(int argc, char *argv[])
 #ifdef CONFIG_NSH_TELNET_LOGIN
   if (nsh_telnetlogin(pstate) != OK)
     {
-      nsh_exit(&pstate->cn_vtbl, 1);
+      nsh_exit(vtbl, 1);
       return -1; /* nsh_exit does not return */
     }
 #endif /* CONFIG_NSH_TELNET_LOGIN */
@@ -293,9 +296,24 @@ int nsh_telnetmain(int argc, char *argv[])
    * readline().
    */
 
-  /* Present the NSH greeting */
+  /* Present a greeting and possibly a Message of the Day (MOTD) */
 
   fputs(g_nshgreeting, pstate->cn_outstream);
+
+#ifdef CONFIG_NSH_MOTD
+# ifdef CONFIG_NSH_PLATFORM_MOTD
+  /* Output the platform message of the day */
+
+  platform_motd(vtbl->iobuffer, IOBUFFERSIZE);
+  fprintf(pstate->cn_outstream, "%s/n", vtbl->iobuffer);
+
+# else
+  /* Output the fixed message of the day */
+
+  fprintf(pstate->cn_outstream, "%s/n", g_nshmotd);
+# endif
+#endif
+
   fflush(pstate->cn_outstream);
 
   /* Execute the startup script.  If standard console is also defined, then
@@ -304,13 +322,13 @@ int nsh_telnetmain(int argc, char *argv[])
    */
 
 #if defined(CONFIG_NSH_ROMFSETC) && !defined(CONFIG_NSH_CONSOLE)
-  (void)nsh_initscript(&pstate->cn_vtbl);
+  (void)nsh_initscript(vtbl);
 #endif
 
   /* Execute the login script */
 
 #ifdef CONFIG_NSH_ROMFSRC
-  (void)nsh_loginscript(&pstate->cn_vtbl);
+  (void)nsh_loginscript(vtbl);
 #endif
 
   /* Then enter the command line parsing loop */
@@ -328,20 +346,20 @@ int nsh_telnetmain(int argc, char *argv[])
         {
           /* Parse process the received Telnet command */
 
-          (void)nsh_parse(&pstate->cn_vtbl, pstate->cn_line);
+          (void)nsh_parse(vtbl, pstate->cn_line);
           fflush(pstate->cn_outstream);
         }
       else
         {
           fprintf(pstate->cn_outstream, g_fmtcmdfailed, "nsh_telnetmain",
                   "fgets", NSH_ERRNO);
-          nsh_exit(&pstate->cn_vtbl, 1);
+          nsh_exit(vtbl, 1);
         }
     }
 
   /* Clean up */
 
-  nsh_exit(&pstate->cn_vtbl, 0);
+  nsh_exit(vtbl, 0);
 
   /* We do not get here, but this is necessary to keep some compilers happy */