mu: improve query interface.

* include/mailutils/cfg.h (mu_cfg_node) <parent>: New member.
(MU_CFG_FMT_VALUE_ONLY)
(MU_CFG_FMT_PARAM_PATH): New flags.
* libmailutils/cfg/format.c (format_path): New static.
(format_node,format_node_end): Handle new flags.
(mu_cfg_format_node): Clear MU_CFG_FMT_VALUE_ONLY if the
requested node is mu_cfg_node_statement.
* libmailutils/cfg/parser.y: Set node parents.
(mu_cfg_find_node): Fix coredump.
* mu/query.c: New options --value and --path.

@@ -69,6 +69,7 @@ struct mu_cfg_node
   char *tag;
   mu_config_value_t *label;
   mu_list_t nodes;   /* a list of mu_cfg_node_t */
+  struct mu_cfg_node *parent; /* parent node */
 };
 
 struct mu_cfg_tree
@@ -250,8 +251,10 @@ int mu_cfg_parse_boolean (const char *str, int *res);
 extern int mu_cfg_parser_verbose;
 extern size_t mu_cfg_error_count;
 
-#define MU_CFG_FMT_LOCUS 0x01
-  
+#define MU_CFG_FMT_LOCUS      0x01
+#define MU_CFG_FMT_VALUE_ONLY 0x02
+#define MU_CFG_FMT_PARAM_PATH 0x04
+
 void mu_cfg_format_docstring (mu_stream_t stream, const char *docstring,
 			      int level);
 void mu_cfg_format_parse_tree (mu_stream_t stream, struct mu_cfg_tree *tree,

@@ -129,6 +129,25 @@ format_value (struct tree_print *tp, mu_config_value_t *val)
     }
 }
 
+static void
+format_path (struct tree_print *tp, const mu_cfg_node_t *node, int delim)
+{
+  char c;
+  
+  if (node->parent)
+    format_path (tp, node->parent, MU_CFG_PATH_DELIM);
+
+  mu_stream_write (tp->stream, node->tag, strlen (node->tag), NULL);
+  if (node->type == mu_cfg_node_statement && node->label)
+    {
+      mu_stream_write (tp->stream, "=\"", 2, NULL);
+      format_value (tp, node->label);
+      mu_stream_write (tp->stream, "\"", 1, NULL);
+    }
+  c = delim;
+  mu_stream_write (tp->stream, &c, 1, NULL);
+}
+
 static int
 format_node (const mu_cfg_node_t *node, void *data)
 {
@@ -147,25 +166,39 @@ format_node (const mu_cfg_node_t *node, void *data)
       break;
 
     case mu_cfg_node_statement:
-      {
-	mu_stream_write (tp->stream, node->tag, strlen (node->tag), NULL);
-	if (node->label)
-	  {
-	    mu_stream_write (tp->stream, " ", 1, NULL);
-	    format_value (tp, node->label);
-	  }
-	mu_stream_write (tp->stream, " {", 2, NULL);
-	tp->level++;
-      }
+      if (tp->flags & MU_CFG_FMT_PARAM_PATH)
+	return MU_CFG_ITER_OK;
+      else
+	{
+	  mu_stream_write (tp->stream, node->tag, strlen (node->tag), NULL);
+	  if (node->label)
+	    {
+	      mu_stream_write (tp->stream, " ", 1, NULL);
+	      format_value (tp, node->label);
+	    }
+	  mu_stream_write (tp->stream, " {", 2, NULL);
+	  tp->level++;
+	}
       break;
 
     case mu_cfg_node_param:
-      mu_stream_write (tp->stream, node->tag, strlen (node->tag), NULL);
-      if (node->label)
+      if (tp->flags & MU_CFG_FMT_VALUE_ONLY)
+	format_value (tp, node->label);
+      else if (tp->flags & MU_CFG_FMT_PARAM_PATH)
 	{
+	  format_path (tp, node, ':');
 	  mu_stream_write (tp->stream, " ", 1, NULL);
 	  format_value (tp, node->label);
-	  mu_stream_write (tp->stream, ";", 1, NULL);
+	}
+      else
+	{
+	  mu_stream_write (tp->stream, node->tag, strlen (node->tag), NULL);
+	  if (node->label)
+	    {
+	      mu_stream_write (tp->stream, " ", 1, NULL);
+	      format_value (tp, node->label);
+	      mu_stream_write (tp->stream, ";", 1, NULL);
+	    }
 	}
       break;
     }
@@ -177,9 +210,12 @@ static int
 format_node_end (const mu_cfg_node_t *node, void *data)
 {
   struct tree_print *tp = data;
-  tp->level--;
-  format_level (tp->stream, tp->level);
-  mu_stream_write (tp->stream, "};\n", 3, NULL);
+  if (!(tp->flags & MU_CFG_FMT_PARAM_PATH))
+    {
+      tp->level--;
+      format_level (tp->stream, tp->level);
+      mu_stream_write (tp->stream, "};\n", 3, NULL);
+    }
   return MU_CFG_ITER_OK;
 }
 
@@ -205,7 +241,9 @@ void
 mu_cfg_format_node (mu_stream_t stream, const mu_cfg_node_t *node, int flags)
 {
   struct tree_print t;
-  
+
+  if (node->type == mu_cfg_node_statement)
+    flags &= ~MU_CFG_FMT_VALUE_ONLY;
   t.flags = flags;
   t.level = 0;
   t.stream = stream;

@@ -77,6 +77,14 @@ config_value_dup (mu_config_value_t *src)
     }
 }
 
+static int
+_node_set_parent (void *item, void *data)
+{
+  struct mu_cfg_node *node = item;
+  node->parent = data;
+  return 0;
+}
+
 static mu_cfg_node_t *
 mu_cfg_alloc_node (enum mu_cfg_node_type type, struct mu_locus *loc,
 		   const char *tag, mu_config_value_t *label,
@@ -93,6 +101,7 @@ mu_cfg_alloc_node (enum mu_cfg_node_type type, struct mu_locus *loc,
   strcpy (p, tag);
   np->label = label;
   np->nodes = nodelist;
+  np->parent = NULL;
   return np;
 }
 
@@ -220,13 +229,12 @@ block   : ident tag '{' '}' opt_sc
 	    $$ = mu_cfg_alloc_node (mu_cfg_node_statement, &$1.locus,
 				    $1.name, $2,
 				    NULL);
-
 	  }
 	| ident tag '{' stmtlist '}' opt_sc
 	  {
 	    $$ = mu_cfg_alloc_node (mu_cfg_node_statement, &$1.locus,
 				    $1.name, $2, $4);
-
+	    mu_list_do ($4, _node_set_parent, $$);
 	  }
 	;
 
@@ -1752,23 +1760,27 @@ mu_cfg_find_node (mu_cfg_tree_t *tree, const char *path, mu_cfg_node_t **pval)
 {
   int rc;
   struct find_data data;
-  struct mu_cfg_iter_closure clos;
 
   rc = split_cfg_path (path, &data.argc, &data.argv);
   if (rc)
     return rc;
   data.tag = 0;
-  parse_tag (&data);
-
-  clos.beg = node_finder;
-  clos.end = NULL;
-  clos.data = &data;
-  rc = mu_cfg_preorder (tree->nodes, &clos);
-  destroy_value (data.label);
-  if (rc)
+  if (data.argc)
     {
-      *pval = (mu_cfg_node_t *) data.node;
-      return 0;
+      struct mu_cfg_iter_closure clos;
+
+      parse_tag (&data);
+
+      clos.beg = node_finder;
+      clos.end = NULL;
+      clos.data = &data;
+      rc = mu_cfg_preorder (tree->nodes, &clos);
+      destroy_value (data.label);
+      if (rc)
+	{
+	  *pval = (mu_cfg_node_t *) data.node;
+	  return 0;
+	}
     }
   return MU_ERR_NOENT;
 }
@@ -1798,6 +1810,7 @@ mu_cfg_create_subtree (const char *path, mu_cfg_node_t **pnode)
       mu_list_t nodelist = NULL;
       mu_config_value_t *label = NULL;
       char *q = argv[i], *p;
+      mu_cfg_node_t *parent;
       
       type = mu_cfg_node_statement;
       do
@@ -1823,7 +1836,10 @@ mu_cfg_create_subtree (const char *path, mu_cfg_node_t **pnode)
 	  mu_cfg_create_node_list (&nodelist);
 	  mu_list_append (nodelist, node);
 	}
-      node = mu_cfg_alloc_node (type, &locus, argv[i], label, nodelist);
+      parent = mu_cfg_alloc_node (type, &locus, argv[i], label, nodelist);
+      if (node)
+	node->parent = parent;
+      node = parent;
     }
 
   mu_argcv_free (argc, argv);

@@ -29,12 +29,22 @@ char query_docstring[] = N_("query configuration values");
 static char query_args_doc[] = N_("path [path...]");
 
 char *file_name;
-int verbose_option;
+int fmtflags = 0;
+
+enum {
+  VALUE_OPTION = 256,
+  PATH_OPTION
+};
 
 static struct argp_option query_options[] = {
   { "file", 'f', N_("FILE"), 0,
     N_("query configuration values from FILE (default mailutils.rc)"),
     0 },
+  { "value", VALUE_OPTION, NULL, 0,
+    N_("display parameter values only"),
+    0 },
+  { "path", PATH_OPTION, NULL, 0,
+    N_("display parameters as paths") },
   { "verbose", 'v', NULL, 0,
     N_("increase output verbosity"), 0},
   { NULL }
@@ -50,7 +60,15 @@ query_parse_opt (int key, char *arg, struct argp_state *state)
       break;
 
     case 'v':
-      verbose_option++;
+      fmtflags |= MU_CFG_FMT_LOCUS;
+      break;
+
+    case VALUE_OPTION:
+      fmtflags |= MU_CFG_FMT_VALUE_ONLY;
+      break;
+      
+    case PATH_OPTION:
+      fmtflags |= MU_CFG_FMT_PARAM_PATH;
       break;
       
     default:
@@ -74,7 +92,6 @@ mutool_query (int argc, char **argv)
 {
   int index;
   mu_cfg_tree_t *tree = NULL;
-  int fmtflags = 0;
   
   if (argp_parse (&query_argp, argc, argv, ARGP_IN_ORDER, &index, NULL))
     return 1;
@@ -99,8 +116,6 @@ mutool_query (int argc, char **argv)
     return 1;
   if (!tree)
     return 0;
-  if (verbose_option)
-    fmtflags = MU_CFG_FMT_LOCUS;
   for ( ; argc > 0; argc--, argv++)
     {
       char *path = *argv;