New wordsplit call: mu_worsplit_append

* include/mailutils/wordsplit.h (mu_wordsplit_append): New proto.
* libmailutils/string/wordsplit.c (mu_wordsplit_append): New function.
* libmailutils/tests/wordsplit.at: Two more tests cases for
mu_wordsplit_append.
* libmailutils/tests/wsp.c: Accept extra arguments to append using
the new function.

@@ -241,6 +241,7 @@ void mu_wordsplit_free_words (mu_wordsplit_t *ws);
 void mu_wordsplit_free_envbuf (mu_wordsplit_t *ws);
 
 int mu_wordsplit_get_words (mu_wordsplit_t *ws, size_t *wordc, char ***wordv);
+int mu_wordsplit_append (struct mu_wordsplit *wsp, int argc, char **argv);
 
 int mu_wordsplit_c_unquote_char (int c);
 int mu_wordsplit_c_quote_char (int c);

@@ -674,7 +674,35 @@ mu_wordsplit_finish (struct mu_wordsplit *wsp)
   return 0;
 }
 
-
+int
+mu_wordsplit_append (struct mu_wordsplit *wsp, int argc, char **argv)
+{
+  int rc;
+  size_t i;
+  
+  rc = alloc_space (wsp, wsp->ws_wordc + argc + 1);
+  if (rc)
+    return rc;
+  for (i = 0; i < argc; i++)
+    {
+      char *newstr = strdup (argv[i]);
+      if (!newstr)
+	{
+	  while (i > 0)
+	    {
+	      free (wsp->ws_wordv[wsp->ws_offs + wsp->ws_wordc + i - 1]);
+	      wsp->ws_wordv[wsp->ws_offs + wsp->ws_wordc + i - 1] = NULL;
+	      i--;
+	    }
+	  return _wsplt_nomem (wsp);
+	}
+      wsp->ws_wordv[wsp->ws_offs + wsp->ws_wordc + i] = newstr;
+    }
+  wsp->ws_wordc += i;
+  wsp->ws_wordv[wsp->ws_offs + wsp->ws_wordc] = NULL;
+  return 0;
+}
+
 /* Variable expansion */
 static int
 node_split_prefix (struct mu_wordsplit *wsp,

@@ -623,5 +623,32 @@ EOT
 [no files match pattern dir/*.d
 ])
 AT_CLEANUP
+
+TESTWSP([append],[],[-- extra arguments follow],
+[some words and],
+[NF: 6
+0: some
+1: words
+2: and
+3: extra
+4: arguments
+5: follow
+])
+
+TESTWSP([append + dooffs + env],[],
+[dooffs 2 preface words V=2 -- extra arguments follow],
+[some words and var=$V],
+[NF: 7 (2)
+(0): preface
+(1): words
+2: some
+3: words
+4: and
+5: var=2
+6: extra
+7: arguments
+8: follow
+])
+
 
 m4_popdef([TESTWSP])

@@ -77,7 +77,7 @@ help ()
 {
   size_t i;
   
-  printf ("usage: %s [options] [VAR=VALUE...]\n", progname);
+  printf ("usage: %s [options] [VAR=VALUE...] [-- EXTRA...]\n", progname);
   printf ("options are:\n");
   printf (" [-]trimnl\n");
   printf (" [-]plaintext\n");
@@ -314,6 +314,8 @@ main (int argc, char **argv)
   size_t fenvidx = 0;
   size_t fenvmax = sizeof (fenvbase) / sizeof (fenvbase[0]);
   int use_env = env_sys;
+  int appendc = 0;
+  char **appendv = NULL;
   
   progname = argv[0];
 
@@ -326,6 +328,12 @@ main (int argc, char **argv)
 
       if (opt[0] == '-')
 	{
+	  if (opt[1] == '-' && opt[2] == 0)
+	    {
+	      appendc = argc - i - 1;
+	      appendv = argv + i + 1;
+	      break;
+	    }
 	  negate = 1;
 	  opt++;
 	}
@@ -588,6 +596,17 @@ main (int argc, char **argv)
 	  offarg = 0;
 	}
 
+      if (appendc)
+	{
+	  rc = mu_wordsplit_append (&ws, appendc, appendv);
+	  if (rc)
+	    {
+	      if (!(wsflags & MU_WRDSF_SHOWERR))
+		mu_wordsplit_perror (&ws);
+	      continue;
+	    }
+	}
+      
       wsflags |= MU_WRDSF_REUSE | (ws.ws_flags & MU_WRDSF_ENV);
       printf ("NF: %lu", (unsigned long) ws.ws_wordc);
       if (wsflags & MU_WRDSF_DOOFFS)