Reorganize source tree to use single autotools instance

Change-Id: I7b51f88292e057c6443b12224486f2d0c9f8ae23
Signed-off-by: Damjan Marion <damarion@cisco.com>

1 files changed, 1007 insertions, 0 deletions

diff --git a/src/vlib/parse.c b/src/vlib/parse.c
new file mode 100644
index 00000000000..1c4500ce85a
--- /dev/null
+++ b/src/vlib/parse.c
@@ -0,0 +1,1007 @@
+/*
+ * Copyright (c) 2015 Cisco and/or its affiliates.
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at:
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+#include <vlib/parse.h>
+
+#define PARSE_DEBUG 0
+
+u16 word_type_index, number_type_index, eof_type_index, rule_eof_type_index,
+  plus_type_index, minus_type_index, star_type_index, slash_type_index,
+  lpar_type_index, rpar_type_index;
+
+u8 *
+format_vlib_parse_value (u8 * s, va_list * args)
+{
+  vlib_parse_main_t *pm = va_arg (*args, vlib_parse_main_t *);
+  vlib_parse_type_t *type;
+  vlib_parse_value_t *v;
+  u16 type_index;
+
+  s = format (s, "%d items:\n", vec_len (pm->parse_value));
+  vec_foreach (v, pm->parse_value)
+  {
+    type_index = v->type;
+    type = pool_elt_at_index (pm->parse_types, type_index);
+    if (type->format_value)
+      s = format (s, "[%d]: %U\n", v - pm->parse_value,
+		  type->format_value, v);
+    else
+      s = format (s, "[%d]: (nofun)\n", v - pm->parse_value);
+  }
+  return s;
+}
+
+static u8 *
+format_vlib_parse_match (u8 * s, va_list * args)
+{
+  vlib_parse_match_t m = va_arg (*args, vlib_parse_match_t);
+  char *t = 0;
+  switch (m)
+    {
+#define _(a) case VLIB_PARSE_##a: t = #a; break;
+      foreach_parse_match_type
+#undef _
+    default:
+      t = 0;
+      break;
+    }
+
+  if (t)
+    return format (s, "%s", t);
+  else
+    return format (s, "unknown 0x%x", m);
+}
+
+static u8 *
+format_vlib_parse_item (u8 * s, va_list * args)
+{
+  vlib_parse_main_t *pm = va_arg (*args, vlib_parse_main_t *);
+  vlib_parse_item_t *item = va_arg (*args, vlib_parse_item_t *);
+  vlib_parse_type_t *type = pool_elt_at_index (pm->parse_types, item->type);
+
+  if (item->type == word_type_index)
+    s = format (s, "%s", item->value.as_pointer);
+  else
+    s = format (s, "<%s>", type->name);
+  return s;
+}
+
+static u8 *
+format_vlib_parse_graph (u8 * s, va_list * args)
+{
+  vlib_parse_main_t *pm = va_arg (*args, vlib_parse_main_t *);
+  vlib_parse_graph_t *node = va_arg (*args, vlib_parse_graph_t *);
+  vlib_parse_item_t *item;
+  vlib_parse_type_t *type;
+
+  /* $$$ hash table */
+  /* *INDENT-OFF* */
+  pool_foreach (type, pm->parse_types,
+                ({
+                  if (type->rule_index == node - pm->parse_graph)
+                    s = format (s, "\n<%s>\n", type->name);
+                }));
+/* *INDENT-ON* */
+
+  if (pm->root_index == (node - pm->parse_graph))
+    s = format (s, "\n<root>\n");
+
+  item = pool_elt_at_index (pm->parse_items, node->item);
+
+  s = format (s, "[%d] %U ", node - pm->parse_graph,
+	      format_vlib_parse_item, pm, item);
+
+  if (node->peer == (u32) ~ 0)
+    s = format (s, "peer nil  ");
+  else
+    s = format (s, "peer %4u ", node->peer);
+
+  if (node->deeper == (u32) ~ 0)
+    s = format (s, "deeper nil  ");
+  else
+    s = format (s, "deeper %4u ", node->deeper);
+
+  return s;
+}
+
+void
+dump_parse_graph (void)
+{
+  vlib_parse_main_t *pm = &vlib_parse_main;
+  vlib_parse_graph_t *node;
+
+  /* *INDENT-OFF* */
+  pool_foreach (node, pm->parse_graph, ({
+    fformat(stdout, "%U\n", format_vlib_parse_graph, pm, node);
+  }));
+/* *INDENT-ON* */
+}
+
+always_inline void
+parse_cleanup_value (vlib_parse_main_t * pm, vlib_parse_value_t * pv)
+{
+  vlib_parse_type_t *type = pool_elt_at_index (pm->parse_types, pv->type);
+  if (type->value_cleanup_function)
+    type->value_cleanup_function (pv);
+}
+
+static void
+parse_reset (vlib_parse_main_t * pm, u8 * input)
+{
+  vlib_lex_token_t *t;
+  vlib_parse_value_t *pv;
+
+  vlib_lex_reset (pm->lex_main, input);
+
+  vec_foreach (t, pm->tokens) vlib_lex_cleanup_token (t);
+
+  vec_foreach (pv, pm->parse_value) parse_cleanup_value (pm, pv);
+
+  _vec_len (pm->parse_value) = 0;
+  _vec_len (pm->tokens) = 0;
+  pm->current_token_index = 0;
+}
+
+static void
+parse_help (vlib_parse_main_t * pm, u32 index)
+{
+  vlib_parse_graph_t *node;
+  vlib_parse_item_t *item;
+  vlib_parse_type_t *type;
+  vlib_main_t *vm = pm->vlib_main;
+  u8 *help_input;
+  int i;
+
+  help_input = vec_dup (pm->lex_main->input_vector);
+
+  for (i = vec_len (help_input) - 1; i >= 0; i--)
+    if (help_input[i] == '?')
+      {
+	help_input[i] = 0;
+	_vec_len (help_input) = i;
+	break;
+      }
+
+  for (i = vec_len (help_input) - 1; i >= 0; i--)
+    {
+      if (help_input[i] != ' ' && help_input[i] != '\t')
+	break;
+      help_input[i] = 0;
+      break;
+    }
+  _vec_len (help_input) = i + 1;
+
+  while (index != (u32) ~ 0)
+    {
+      node = pool_elt_at_index (pm->parse_graph, index);
+      item = pool_elt_at_index (pm->parse_items, node->item);
+      type = pool_elt_at_index (pm->parse_types, item->type);
+
+      if (item->type == eof_type_index && vec_len (pm->match_items) == 0)
+	/* do nothing */ ;
+      else if (item->type == word_type_index)
+	vlib_cli_output (vm, "%s %s\n", help_input, item->value.as_pointer);
+      else
+	vlib_cli_output (vm, "%s <%s>\n", help_input, type->name);
+      index = node->peer;
+    }
+  vec_free (help_input);
+}
+
+static vlib_parse_match_t
+parse_eval_internal (vlib_parse_main_t * pm, u32 index)
+{
+  vlib_parse_graph_t *node;
+  vlib_parse_item_t *item;
+  vlib_parse_type_t *type;
+  vlib_parse_value_t value, *pv;
+  vlib_parse_match_t rv;
+  u32 *partial_matches = 0;
+  vlib_lex_token_t *t;
+  u32 save_token_index = (u32) ~ 0, save_match_items = 0;
+  int had_value = 0;
+
+  if (pm->current_token_index >= vec_len (pm->tokens))
+    return VLIB_PARSE_MATCH_FAIL;
+
+  /* current token */
+  t = vec_elt_at_index (pm->tokens, pm->current_token_index);
+
+  /* Help ? */
+  if (PREDICT_FALSE (t->token == VLIB_LEX_qmark))
+    {
+      parse_help (pm, index);
+      _vec_len (pm->match_items) = 0;
+      return VLIB_PARSE_MATCH_DONE;
+    }
+
+  /* Across all peers at this level of the parse graph */
+  while (index != (u32) ~ 0)
+    {
+      node = pool_elt_at_index (pm->parse_graph, index);
+      item = pool_elt_at_index (pm->parse_items, node->item);
+      type = pool_elt_at_index (pm->parse_types, item->type);
+
+      /*
+       * Save the token index. We may have to back up several
+       * trie plies. Type-specific match functions can consume
+       * multiple tokens, and they may not be optimally careful
+       */
+      save_token_index = pm->current_token_index;
+      save_match_items = vec_len (pm->match_items);
+      vec_add1 (pm->match_items, node->item);
+
+      if (PARSE_DEBUG > 1)
+	clib_warning ("Try to match token %U against node %d",
+		      format_vlib_lex_token, pm->lex_main, t, index);
+
+      /* Call the type-specific match function */
+      rv = type->match_function (pm, type, t, &value);
+
+      if (PARSE_DEBUG > 1)
+	clib_warning ("returned %U", format_vlib_parse_match, rv);
+
+      switch (rv)
+	{
+	case VLIB_PARSE_MATCH_VALUE:
+	  /*
+	   * Matched, and returned a value to append to the
+	   * set of args passed to the action function
+	   */
+	  value.type = item->type;
+	  vec_add1 (pm->parse_value, value);
+	  had_value = 1;
+	  /* fallthrough */
+
+	case VLIB_PARSE_MATCH_FULL:
+	unambiguous_partial_match:
+	  /* Consume the matched token */
+	  pm->current_token_index++;
+
+	  /* continue matching along this path */
+	  rv = parse_eval_internal (pm, node->deeper);
+
+	  /* this is not the right path */
+	  if (rv == VLIB_PARSE_MATCH_FAIL)
+	    {
+	      if (had_value)
+		{
+		  /* Delete the value */
+		  value = pm->parse_value[vec_len (pm->parse_value) - 1];
+		  parse_cleanup_value (pm, &value);
+		  _vec_len (pm->parse_value) -= 1;
+		}
+	      /* Continue with the next sibling */
+	      pm->current_token_index = save_token_index;
+	      _vec_len (pm->match_items) = save_match_items;
+	      index = node->peer;
+	      break;
+	    }
+	  return rv;
+
+	case VLIB_PARSE_MATCH_PARTIAL:
+	  /* Partial (substring) match, remember it but keep going */
+	  vec_add1 (partial_matches, node - pm->parse_graph);
+	  index = node->peer;
+	  break;
+
+	case VLIB_PARSE_MATCH_FAIL:
+	  /* Continue with the next sibling */
+	  index = node->peer;
+	  _vec_len (pm->match_items) = save_match_items;
+	  break;
+
+	case VLIB_PARSE_MATCH_DONE:
+	  /* Parse complete, invoke the action function */
+	  if (PARSE_DEBUG > 0)
+	    clib_warning ("parse_value: %U", format_vlib_parse_value, pm);
+
+	  {
+	    vlib_parse_eval_function_t *f = item->value.as_pointer;
+	    if (f)
+	      rv = f (pm, item, pm->parse_value);
+	  }
+
+	  vec_foreach (pv, pm->parse_value) parse_cleanup_value (pm, pv);
+	  _vec_len (pm->parse_value) = 0;
+	  _vec_len (pm->match_items) = 0;
+	  return rv;
+
+	case VLIB_PARSE_MATCH_AMBIGUOUS:
+	case VLIB_PARSE_MATCH_EVAL_FAIL:
+	case VLIB_PARSE_MATCH_RULE:
+	  _vec_len (pm->match_items) = save_match_items;
+	  return rv;
+	}
+    }
+
+  /*
+   * Out of siblings. If we have exactly one partial match
+   * we win
+   */
+  if (vec_len (partial_matches) == 1)
+    {
+      index = partial_matches[0];
+      node = pool_elt_at_index (pm->parse_graph, index);
+      vec_free (partial_matches);
+      goto unambiguous_partial_match;
+    }
+
+  /* Ordinary loser */
+  rv = VLIB_PARSE_MATCH_FAIL;
+
+  /* Ambiguous loser */
+  if (vec_len (partial_matches) > 1)
+    {
+      vec_free (partial_matches);
+      rv = VLIB_PARSE_MATCH_AMBIGUOUS;
+    }
+
+  _vec_len (pm->match_items) = save_match_items;
+  return rv;
+}
+
+vlib_parse_match_t
+rule_match (vlib_parse_main_t * pm, vlib_parse_type_t * type,
+	    vlib_lex_token_t * t, vlib_parse_value_t * valuep)
+{
+  vlib_parse_match_t rv;
+  static int recursion_level;
+
+  if (PARSE_DEBUG > 1)
+    clib_warning ("[%d]: try to match type %s graph index %d",
+		  recursion_level, type->name, type->rule_index);
+  recursion_level++;
+  rv = parse_eval_internal (pm, type->rule_index);
+  recursion_level--;
+
+  /* Break the recusive unwind here... */
+  if (rv == VLIB_PARSE_MATCH_RULE)
+    {
+      if (PARSE_DEBUG > 1)
+	clib_warning ("[%d]: type %s matched", recursion_level, type->name);
+
+      return VLIB_PARSE_MATCH_FULL;
+    }
+  else
+    {
+      if (PARSE_DEBUG > 1)
+	clib_warning ("[%d]: type %s returns %U", recursion_level, type->name,
+		      format_vlib_parse_match, rv);
+    }
+  return rv;
+}
+
+static int
+parse_eval (vlib_parse_main_t * pm, u8 * input)
+{
+  vlib_lex_token_t *t;
+
+  parse_reset (pm, input);
+
+  /* Tokenize the entire input vector */
+  do
+    {
+      vec_add2 (pm->tokens, t, 1);
+      vlib_lex_get_token (pm->lex_main, t);
+    }
+  while (t->token != VLIB_LEX_eof);
+
+  /* Feed it to the parser */
+  return parse_eval_internal (pm, pm->root_index);
+}
+
+/* Temporary vlib stub */
+vlib_parse_match_t
+vlib_parse_eval (u8 * input)
+{
+  return parse_eval (&vlib_parse_main, input);
+}
+
+u16
+parse_type_find_or_create (vlib_parse_main_t * pm, vlib_parse_type_t * t)
+{
+  uword *p;
+  vlib_parse_type_t *n;
+  u8 *name_copy;
+
+  p = hash_get_mem (pm->parse_type_by_name_hash, t->name);
+  if (p)
+    return p[0];
+
+  pool_get (pm->parse_types, n);
+  *n = *t;
+  n->rule_index = (u32) ~ 0;
+
+  name_copy = format (0, "%s%c", n->name, 0);
+
+  hash_set_mem (pm->parse_type_by_name_hash, name_copy, n - pm->parse_types);
+  return n - pm->parse_types;
+}
+
+u16
+parse_type_find_by_name (vlib_parse_main_t * pm, char *name)
+{
+  uword *p;
+
+  p = hash_get_mem (pm->parse_type_by_name_hash, name);
+  if (p)
+    return p[0];
+
+  return (u16) ~ 0;
+}
+
+u32
+parse_item_find_or_create (vlib_parse_main_t * pm, vlib_parse_item_t * item)
+{
+  uword *p;
+  vlib_parse_item_t *i;
+
+  /* Exact match the entire item */
+  p = mhash_get (&pm->parse_item_hash, item);
+  if (p)
+    return p[0];
+
+  pool_get (pm->parse_items, i);
+  *i = *item;
+
+  mhash_set (&pm->parse_item_hash, i, i - pm->parse_items, 0);
+  return i - pm->parse_items;
+}
+
+static void
+parse_type_and_graph_init (vlib_parse_main_t * pm)
+{
+  u32 eof_index;
+  vlib_parse_type_t type;
+  vlib_parse_item_t item;
+
+  memset (&type, 0, sizeof (type));
+
+#define foreach_token_type                      \
+  _ (eof)                                       \
+  _ (rule_eof)                                  \
+  _ (word)                                      \
+  _ (number)                                    \
+  _ (plus)                                      \
+  _ (minus)                                     \
+  _ (star)                                      \
+  _ (slash)                                     \
+  _ (lpar)                                      \
+  _ (rpar)
+
+#define _(a) a##_type_index = parse_type_find_by_name (pm, #a);
+  foreach_token_type
+#undef _
+    memset (&item, 0, sizeof (item));
+  item.type = eof_type_index;
+
+  eof_index = parse_item_find_or_create (pm, &item);
+  pm->root_index = (u32) ~ 0;
+
+#if 0
+  pool_get (pm->parse_graph, g);
+  memset (g, 0xff, sizeof (*g));
+  g->item = eof_index;
+  pm->root_index = 0;
+#endif
+}
+
+
+
+static void
+tokenize (vlib_parse_main_t * pm, parse_registration_t * pr)
+{
+  vlib_lex_token_t *t;
+  pm->register_input = format (pm->register_input,
+			       "%s%c", pr->initializer, 0);
+
+  parse_reset (pm, pm->register_input);
+
+  do
+    {
+      vec_add2 (pm->tokens, t, 1);
+      vlib_lex_get_token (pm->lex_main, t);
+    }
+  while (t->token != VLIB_LEX_eof);
+  _vec_len (pm->register_input) = 0;
+}
+
+static int
+is_typed_rule (vlib_parse_main_t * pm)
+{
+  vlib_lex_token_t *t = vec_elt_at_index (pm->tokens, 0);
+
+  /* <mytype> = blah blah blah */
+  if (vec_len (pm->tokens) >= 4
+      && t[0].token == VLIB_LEX_lt
+      && t[1].token == VLIB_LEX_word
+      && t[2].token == VLIB_LEX_gt && t[3].token == VLIB_LEX_equals)
+    return 1;
+  return 0;
+}
+
+static int
+token_matches_graph_node (vlib_parse_main_t * pm,
+			  vlib_lex_token_t * t,
+			  vlib_parse_graph_t * node,
+			  vlib_parse_item_t * item,
+			  vlib_parse_type_t * type, u32 * token_increment)
+{
+  /* EOFs don't match */
+  if (t->token == VLIB_LEX_eof)
+    return 0;
+
+  /* New chain element is a word */
+  if (t->token == VLIB_LEX_word)
+    {
+      /* but the item in hand is not a word */
+      if (item->type != word_type_index)
+	return 0;
+
+      /* Or it's not this particular word */
+      if (strcmp (t->value.as_pointer, item->value.as_pointer))
+	return 0;
+      *token_increment = 1;
+      return 1;
+    }
+  /* New chain element is a type-name: < TYPE-NAME > */
+  if (t->token == VLIB_LEX_lt)
+    {
+      u16 token_type_index;
+
+      /* < TYPE > */
+      if (t[1].token != VLIB_LEX_word || t[2].token != VLIB_LEX_gt)
+	{
+	  clib_warning (0, "broken type name in '%s'", pm->register_input);
+	  return 0;
+	}
+
+      token_type_index = parse_type_find_by_name (pm, t[1].value.as_pointer);
+      if (token_type_index == (u16) ~ 0)
+	{
+	  clib_warning (0, "unknown type '%s'", t[1].value.as_pointer);
+	  return 0;
+	}
+
+      /* Its a known type but does not match. */
+      if (item->type != token_type_index)
+	return 0;
+
+      *token_increment = 3;
+      return 1;
+    }
+  clib_warning ("BUG: t->token = %d", t->token);
+  return 0;
+}
+
+u32
+generate_subgraph_from_tokens (vlib_parse_main_t * pm,
+			       vlib_lex_token_t * t,
+			       u32 * new_subgraph_depth,
+			       parse_registration_t * pr, int not_a_rule)
+{
+  vlib_parse_graph_t *g, *last_g;
+  vlib_parse_item_t new_item;
+  u32 rv = (u32) ~ 0, new_item_index, last_index = (u32) ~ 0;
+  u16 token_type_index;
+  u32 depth = 0;
+
+  while (t < pm->tokens + vec_len (pm->tokens))
+    {
+      memset (&new_item, 0, sizeof (new_item));
+
+      if (t->token == VLIB_LEX_word)
+	{
+	  new_item.type = word_type_index;
+	  new_item.value.as_pointer = vec_dup ((u8 *) t->value.as_pointer);
+	  new_item_index = parse_item_find_or_create (pm, &new_item);
+	  t++;
+	}
+      else if (t->token == VLIB_LEX_lt)
+	{
+	  if (t[1].token != VLIB_LEX_word || t[2].token != VLIB_LEX_gt)
+	    {
+	      clib_warning ("broken type name in '%s'", pm->register_input);
+	      goto screwed;
+	    }
+	  token_type_index = parse_type_find_by_name (pm,
+						      t[1].value.as_pointer);
+	  if (token_type_index == (u16) ~ 0)
+	    {
+	      clib_warning ("unknown type 2 '%s'", t[1].value.as_pointer);
+	      goto screwed;
+	    }
+
+	  new_item.type = token_type_index;
+	  new_item.value.as_pointer = 0;
+	  new_item_index = parse_item_find_or_create (pm, &new_item);
+	  t += 3;		/* skip < <type-name> and > */
+	}
+      else if (t->token == VLIB_LEX_eof)
+	{
+	screwed:
+	  new_item.type = not_a_rule ? eof_type_index : rule_eof_type_index;
+	  new_item.value.as_pointer = pr->eof_match;
+	  new_item_index = parse_item_find_or_create (pm, &new_item);
+	  t++;
+	}
+      else
+	{
+	  clib_warning ("unexpected token %U index %d in '%s'",
+			format_vlib_lex_token, pm->lex_main, t,
+			t - pm->tokens, pm->register_input);
+	  goto screwed;
+	}
+
+      pool_get (pm->parse_graph, g);
+      memset (g, 0xff, sizeof (*g));
+      g->item = new_item_index;
+      depth++;
+
+      if (rv == (u32) ~ 0)
+	{
+	  rv = g - pm->parse_graph;
+	  last_index = rv;
+	}
+      else
+	{
+	  last_g = pool_elt_at_index (pm->parse_graph, last_index);
+	  last_index = last_g->deeper = g - pm->parse_graph;
+	}
+    }
+  *new_subgraph_depth = depth;
+  return rv;
+}
+
+static u32
+measure_depth (vlib_parse_main_t * pm, u32 index)
+{
+  vlib_parse_graph_t *node;
+  vlib_parse_item_t *item;
+  u32 max = 0;
+  u32 depth;
+
+  if (index == (u32) ~ 0)
+    return 0;
+
+  node = pool_elt_at_index (pm->parse_graph, index);
+  item = pool_elt_at_index (pm->parse_items, node->item);
+
+  if (item->type == eof_type_index)
+    return 1;
+
+  while (index != (u32) ~ 0)
+    {
+      node = pool_elt_at_index (pm->parse_graph, index);
+      depth = measure_depth (pm, node->deeper);
+      if (max < depth)
+	max = depth;
+      index = node->peer;
+    }
+
+  return max + 1;
+}
+
+static void
+add_subgraph_to_graph (vlib_parse_main_t * pm,
+		       u32 last_matching_index,
+		       u32 graph_root_index,
+		       u32 new_subgraph_index, u32 new_subgraph_depth)
+{
+  vlib_parse_graph_t *parent_node;
+  int new_subgraph_longest = 1;
+  u32 current_peer_index;
+  u32 current_depth;
+  vlib_parse_graph_t *current_peer = 0;
+  vlib_parse_graph_t *new_subgraph_node =
+    pool_elt_at_index (pm->parse_graph, new_subgraph_index);
+
+  /*
+   * Case 1: top-level peer. Splice into the top-level
+   * peer chain according to rule depth
+   */
+  if (last_matching_index == (u32) ~ 0)
+    {
+      u32 index = graph_root_index;
+      while (1)
+	{
+	  current_peer = pool_elt_at_index (pm->parse_graph, index);
+	  current_depth = measure_depth (pm, index);
+	  if (current_depth < new_subgraph_depth
+	      || current_peer->peer == (u32) ~ 0)
+	    break;
+	  index = current_peer->peer;
+	}
+      new_subgraph_node->peer = current_peer->peer;
+      current_peer->peer = new_subgraph_index;
+      return;
+    }
+
+  parent_node = pool_elt_at_index (pm->parse_graph, last_matching_index);
+  current_peer_index = parent_node->deeper;
+
+  while (current_peer_index != (u32) ~ 0)
+    {
+      current_peer = pool_elt_at_index (pm->parse_graph, current_peer_index);
+      current_depth = measure_depth (pm, current_peer_index);
+      if (current_depth < new_subgraph_depth)
+	break;
+      new_subgraph_longest = 0;
+      current_peer_index = current_peer->peer;
+    }
+
+  ASSERT (current_peer);
+
+  if (new_subgraph_longest)
+    {
+      new_subgraph_node->peer = parent_node->deeper;
+      parent_node->deeper = new_subgraph_index;
+    }
+  else
+    {
+      new_subgraph_node->peer = current_peer->peer;
+      current_peer->peer = new_subgraph_index;
+    }
+}
+
+static clib_error_t *
+parse_register_one (vlib_parse_main_t * pm, parse_registration_t * pr)
+{
+  u32 graph_root_index;
+  u16 subgraph_type_index = (u16) ~ 0;
+  vlib_parse_type_t *subgraph_type = 0;
+  vlib_lex_token_t *t;
+  vlib_parse_graph_t *node;
+  u32 node_index, last_index, token_increment, new_subgraph_index;
+  u32 new_subgraph_depth, last_matching_index;
+  vlib_parse_item_t *item;
+  vlib_parse_type_t *type;
+
+  int use_main_graph = 1;
+
+  tokenize (pm, pr);
+
+  /* A typed rule? */
+  if (is_typed_rule (pm))
+    {
+      /* Get the type and its current subgraph root, if any */
+      t = vec_elt_at_index (pm->tokens, 1);
+      subgraph_type_index = parse_type_find_by_name (pm, t->value.as_pointer);
+      if (subgraph_type_index == (u16) ~ 0)
+	return clib_error_return (0, "undeclared type '%s'",
+				  t->value.as_pointer);
+      subgraph_type =
+	pool_elt_at_index (pm->parse_types, subgraph_type_index);
+      graph_root_index = subgraph_type->rule_index;
+      /* Skip "mytype> = */
+      t += 3;
+      use_main_graph = 0;
+    }
+  else
+    {
+      /* top-level graph */
+      graph_root_index = pm->root_index;
+      t = vec_elt_at_index (pm->tokens, 0);
+    }
+
+  last_matching_index = (u32) ~ 0;
+  last_index = node_index = graph_root_index;
+
+  /* Find the first token which isn't already being parsed */
+  while (t < pm->tokens + vec_len (pm->tokens) && node_index != (u32) ~ 0)
+    {
+      node = pool_elt_at_index (pm->parse_graph, node_index);
+      item = pool_elt_at_index (pm->parse_items, node->item);
+      type = pool_elt_at_index (pm->parse_types, item->type);
+      last_index = node_index;
+
+      if (token_matches_graph_node
+	  (pm, t, node, item, type, &token_increment))
+	{
+	  t += token_increment;
+	  last_matching_index = node_index;
+	  node_index = node->deeper;
+	}
+      else
+	node_index = node->peer;
+    }
+
+  new_subgraph_index =
+    generate_subgraph_from_tokens (pm, t, &new_subgraph_depth, pr,
+				   use_main_graph);
+
+  /* trivial cases: first graph node or first type rule */
+  if (graph_root_index == (u32) ~ 0)
+    {
+      if (use_main_graph)
+	pm->root_index = new_subgraph_index;
+      else
+	subgraph_type->rule_index = new_subgraph_index;
+      return 0;
+    }
+
+  add_subgraph_to_graph (pm, last_matching_index, graph_root_index,
+			 new_subgraph_index, new_subgraph_depth);
+  return 0;
+}
+
+static clib_error_t *
+parse_register (vlib_main_t * vm,
+		parse_registration_t * lo,
+		parse_registration_t * hi, vlib_parse_main_t * pm)
+{
+  parse_registration_t *pr;
+
+  for (pr = lo; pr < hi; pr = vlib_elf_section_data_next (pr, 0))
+    vec_add1 (pm->parse_registrations, pr);
+
+  return 0;
+}
+
+static clib_error_t *
+parse_register_one_type (vlib_parse_main_t * pm, vlib_parse_type_t * rp)
+{
+  (void) parse_type_find_or_create (pm, (vlib_parse_type_t *) rp);
+  return 0;
+}
+
+static clib_error_t *
+parse_type_register (vlib_main_t * vm,
+		     vlib_parse_type_t * lo,
+		     vlib_parse_type_t * hi, vlib_parse_main_t * pm)
+{
+  clib_error_t *error = 0;
+  vlib_parse_type_t *ptr;
+
+  for (ptr = lo; ptr < hi; ptr = vlib_elf_section_data_next (ptr, 0))
+    {
+      error = parse_register_one_type (pm, ptr);
+      if (error)
+	goto done;
+    }
+
+done:
+  return error;
+}
+
+clib_error_t *vlib_stdlex_init (vlib_main_t * vm) __attribute__ ((weak));
+clib_error_t *
+vlib_stdlex_init (vlib_main_t * vm)
+{
+  (void) vlib_lex_add_table ("ignore_everything");
+  return 0;
+}
+
+static int
+compute_rule_length (parse_registration_t * r)
+{
+  int length, i;
+  vlib_parse_main_t *pm = &vlib_parse_main;
+
+  if (r->rule_length)
+    return r->rule_length;
+
+  length = 0;
+
+  tokenize (pm, r);
+  length = vec_len (pm->tokens);
+
+  /* Account for "<foo> = " in "<foo> = bar" etc. */
+  if (is_typed_rule (pm))
+    length -= 2;
+
+  for (i = 0; i < vec_len (pm->tokens); i++)
+    {
+      switch (pm->tokens[i].token)
+	{
+	case VLIB_LEX_lt:
+	case VLIB_LEX_gt:
+	  length -= 1;
+
+	default:
+	  break;
+	}
+    }
+
+  ASSERT (length > 0);
+  r->rule_length = length;
+  return length;
+}
+
+static int
+rule_length_compare (parse_registration_t * r1, parse_registration_t * r2)
+{
+  compute_rule_length (r1);
+  compute_rule_length (r2);
+  /* Descending sort */
+  return r2->rule_length - r1->rule_length;
+}
+
+
+static clib_error_t *
+parse_init (vlib_main_t * vm)
+{
+  vlib_parse_main_t *pm = &vlib_parse_main;
+  vlib_lex_main_t *lm = &vlib_lex_main;
+  vlib_elf_section_bounds_t *b, *bounds;
+  clib_error_t *error = 0;
+  parse_registration_t *rule;
+  int i;
+
+  if ((error = vlib_call_init_function (vm, lex_onetime_init)))
+    return error;
+
+  if ((error = vlib_stdlex_init (vm)))
+    return error;
+
+  if ((error = vlib_call_init_function (vm, parse_builtin_init)))
+    return error;
+
+  pm->vlib_main = vm;
+  pm->lex_main = lm;
+
+  mhash_init (&pm->parse_item_hash, sizeof (u32), sizeof (vlib_parse_item_t));
+  pm->parse_type_by_name_hash = hash_create_string (0, sizeof (u32));
+
+  vec_validate (pm->parse_value, 16);
+  vec_validate (pm->tokens, 16);
+  vec_validate (pm->register_input, 32);
+  vec_validate (pm->match_items, 16);
+
+  _vec_len (pm->parse_value) = 0;
+  _vec_len (pm->tokens) = 0;
+  _vec_len (pm->register_input) = 0;
+  _vec_len (pm->match_items) = 0;
+
+  bounds = vlib_get_elf_section_bounds (vm, "parse_type_registrations");
+  vec_foreach (b, bounds)
+  {
+    error = parse_type_register (vm, b->lo, b->hi, pm);
+    if (error)
+      break;
+  }
+  vec_free (bounds);
+
+  parse_type_and_graph_init (pm);
+
+  bounds = vlib_get_elf_section_bounds (vm, "parse_registrations");
+  vec_foreach (b, bounds)
+  {
+    error = parse_register (vm, b->lo, b->hi, pm);
+    if (error)
+      break;
+  }
+  vec_free (bounds);
+
+  vec_sort_with_function (pm->parse_registrations, rule_length_compare);
+
+  for (i = 0; i < vec_len (pm->parse_registrations); i++)
+    {
+      rule = pm->parse_registrations[i];
+      parse_register_one (pm, rule);
+    }
+
+  return error;
+}
+
+VLIB_INIT_FUNCTION (parse_init);
+
+/*
+ * fd.io coding-style-patch-verification: ON
+ *
+ * Local Variables:
+ * eval: (c-set-style "gnu")
+ * End:
+ */