lib: Improve error reporting from broken config files

* command.h: (config_from_file) Add variable to interface for line
      number reporting.
    * command.c: (config_from_file) Set & increment 'line_num' while parsing.
    * vty.c: (vty_read_file) Report parse errors in the correct order to
      stderr, with added line numbers.

1 files changed, 16 insertions, 7 deletions

diff --git a/lib/vty.c b/lib/vty.c
index 11413576..488f8d5f 100644
--- a/lib/vty.c
+++ b/lib/vty.c
@@ -2229,28 +2229,37 @@ vty_read_file (FILE *confp)
 {
   int ret;
   struct vty *vty;
+  unsigned int line_num = 0;
 
   vty = vty_new ();
-  vty->fd = 0;			/* stdout */
-  vty->type = VTY_TERM;
+  vty->fd = dup(STDERR_FILENO); /* vty_close() will close this */
+  if (vty->fd < 0)
+  {
+    /* Fine, we couldn't make a new fd. vty_close doesn't close stdout. */
+    vty->fd = STDOUT_FILENO;
+  }
+  vty->type = VTY_FILE;
   vty->node = CONFIG_NODE;
   
   /* Execute configuration file */
-  ret = config_from_file (vty, confp);
+  ret = config_from_file (vty, confp, &line_num);
+
+  /* Flush any previous errors before printing messages below */
+  buffer_flush_all (vty->obuf, vty->fd);
 
   if ( !((ret == CMD_SUCCESS) || (ret == CMD_ERR_NOTHING_TODO)) ) 
     {
       switch (ret)
        {
          case CMD_ERR_AMBIGUOUS:
-           fprintf (stderr, "Ambiguous command.\n");
+           fprintf (stderr, "*** Error reading config: Ambiguous command.\n");
            break;
          case CMD_ERR_NO_MATCH:
-           fprintf (stderr, "There is no such command.\n");
+           fprintf (stderr, "*** Error reading config: There is no such command.\n");
            break;
        }
-      fprintf (stderr, "Error occured during reading below line.\n%s\n", 
-	       vty->buf);
+      fprintf (stderr, "*** Error occured processing line %u, below:\n%s\n",
+		       line_num, vty->buf);
       vty_close (vty);
       exit (1);
     }