Merge pull request #195 from opensourcerouting/cli_merge

CLI: independent merge step

12 files changed, 547 insertions, 125 deletions

diff --git a/bgpd/bgp_vty.c b/bgpd/bgp_vty.c
index 01d1768691..b4425297b3 100644
--- a/bgpd/bgp_vty.c
+++ b/bgpd/bgp_vty.c
@@ -2841,7 +2841,7 @@ DEFUN (neighbor_peer_group,
 
 DEFUN (no_neighbor,
        no_neighbor_cmd,
-       "no neighbor <A.B.C.D|X:X::X:X|WORD> [remote-as <(1-4294967295)|internal|external>]",
+       "no neighbor <WORD|<A.B.C.D|X:X::X:X> [remote-as <(1-4294967295)|internal|external>]>",
        NO_STR
        NEIGHBOR_STR
        NEIGHBOR_ADDR_STR2
diff --git a/lib/command.c b/lib/command.c
index d1e11f0617..b166d8e0da 100644
--- a/lib/command.c
+++ b/lib/command.c
@@ -304,6 +304,272 @@ cmd_prompt (enum node_type node)
   return cnode->prompt;
 }
 
+static bool
+cmd_nodes_link (struct graph_node *from, struct graph_node *to)
+{
+  for (size_t i = 0; i < vector_active (from->to); i++)
+    if (vector_slot (from->to, i) == to)
+      return true;
+  return false;
+}
+
+static bool cmd_nodes_equal (struct graph_node *ga, struct graph_node *gb);
+
+/* returns a single node to be excluded as "next" from iteration
+ * - for JOIN_TKN, never continue back to the FORK_TKN
+ * - in all other cases, don't try the node itself (in case of "...")
+ */
+static inline struct graph_node *
+cmd_loopstop(struct graph_node *gn)
+{
+  struct cmd_token *tok = gn->data;
+  if (tok->type == JOIN_TKN)
+    return tok->forkjoin;
+  else
+    return gn;
+}
+
+static bool
+cmd_subgraph_equal (struct graph_node *ga, struct graph_node *gb,
+                    struct graph_node *a_join)
+{
+  size_t i, j;
+  struct graph_node *a_fork, *b_fork;
+  a_fork = cmd_loopstop (ga);
+  b_fork = cmd_loopstop (gb);
+
+  if (vector_active (ga->to) != vector_active (gb->to))
+    return false;
+  for (i = 0; i < vector_active (ga->to); i++)
+    {
+      struct graph_node *cga = vector_slot (ga->to, i);
+
+      for (j = 0; j < vector_active (gb->to); j++)
+        {
+          struct graph_node *cgb = vector_slot (gb->to, i);
+
+          if (cga == a_fork && cgb != b_fork)
+            continue;
+          if (cga == a_fork && cgb == b_fork)
+            break;
+
+          if (cmd_nodes_equal (cga, cgb))
+            {
+              if (cga == a_join)
+                break;
+              if (cmd_subgraph_equal (cga, cgb, a_join))
+                break;
+            }
+        }
+      if (j == vector_active (gb->to))
+        return false;
+    }
+  return true;
+}
+
+/* deep compare -- for FORK_TKN, the entire subgraph is compared.
+ * this is what's needed since we're not currently trying to partially
+ * merge subgraphs */
+static bool
+cmd_nodes_equal (struct graph_node *ga, struct graph_node *gb)
+{
+  struct cmd_token *a = ga->data, *b = gb->data;
+
+  if (a->type != b->type || a->allowrepeat != b->allowrepeat)
+    return false;
+  if (a->type < SPECIAL_TKN && strcmp (a->text, b->text))
+    return false;
+  /* one a ..., the other not. */
+  if (cmd_nodes_link (ga, ga) != cmd_nodes_link (gb, gb))
+    return false;
+
+  switch (a->type)
+    {
+    case RANGE_TKN:
+      return a->min == b->min && a->max == b->max;
+
+    case FORK_TKN:
+      /* one is keywords, the other just option or selector ... */
+      if (cmd_nodes_link (a->forkjoin, ga) != cmd_nodes_link (b->forkjoin, gb))
+        return false;
+      if (cmd_nodes_link (ga, a->forkjoin) != cmd_nodes_link (gb, b->forkjoin))
+        return false;
+      return cmd_subgraph_equal (ga, gb, a->forkjoin);
+
+    default:
+      return true;
+    }
+}
+
+static void
+cmd_fork_bump_attr (struct graph_node *gn, struct graph_node *join,
+                    u_char attr)
+{
+  size_t i;
+  struct cmd_token *tok = gn->data;
+  struct graph_node *stop = cmd_loopstop (gn);
+
+  tok->attr = attr;
+  for (i = 0; i < vector_active (gn->to); i++)
+    {
+      struct graph_node *next = vector_slot (gn->to, i);
+      if (next == stop || next == join)
+        continue;
+      cmd_fork_bump_attr (next, join, attr);
+    }
+}
+
+/* move an entire subtree from the temporary graph resulting from
+ * parse() into the permanent graph for the command node.
+ *
+ * this touches rather deeply into the graph code unfortunately.
+ */
+static void
+cmd_reparent_tree (struct graph *fromgraph, struct graph *tograph,
+                   struct graph_node *node)
+{
+  struct graph_node *stop = cmd_loopstop (node);
+  size_t i;
+
+  for (i = 0; i < vector_active (fromgraph->nodes); i++)
+    if (vector_slot (fromgraph->nodes, i) == node)
+      {
+        /* agressive iteration punching through subgraphs - may hit some
+         * nodes twice.  reparent only if found on old graph */
+        vector_unset (fromgraph->nodes, i);
+        vector_set (tograph->nodes, node);
+        break;
+      }
+
+  for (i = 0; i < vector_active (node->to); i++)
+    {
+      struct graph_node *next = vector_slot (node->to, i);
+      if (next != stop)
+        cmd_reparent_tree (fromgraph, tograph, next);
+    }
+}
+
+static void
+cmd_free_recur (struct graph *graph, struct graph_node *node,
+                struct graph_node *stop)
+{
+  struct graph_node *next, *nstop;
+
+  for (size_t i = vector_active (node->to); i; i--)
+    {
+      next = vector_slot (node->to, i - 1);
+      if (next == stop)
+        continue;
+      nstop = cmd_loopstop (next);
+      if (nstop != next)
+        cmd_free_recur (graph, next, nstop);
+      cmd_free_recur (graph, nstop, stop);
+    }
+  graph_delete_node (graph, node);
+}
+
+static void
+cmd_free_node (struct graph *graph, struct graph_node *node)
+{
+  struct cmd_token *tok = node->data;
+  if (tok->type == JOIN_TKN)
+    cmd_free_recur (graph, tok->forkjoin, node);
+  graph_delete_node (graph, node);
+}
+
+/* recursive graph merge.  call with
+ *   old ~= new
+ * (which holds true for old == START_TKN, new == START_TKN)
+ */
+static void
+cmd_merge_nodes (struct graph *oldgraph, struct graph *newgraph,
+                 struct graph_node *old, struct graph_node *new,
+                 int direction)
+{
+  struct cmd_token *tok;
+  struct graph_node *old_skip, *new_skip;
+  old_skip = cmd_loopstop (old);
+  new_skip = cmd_loopstop (new);
+
+  assert (direction == 1 || direction == -1);
+
+  tok = old->data;
+  tok->refcnt += direction;
+
+  size_t j, i;
+  for (j = 0; j < vector_active (new->to); j++)
+    {
+      struct graph_node *cnew = vector_slot (new->to, j);
+      if (cnew == new_skip)
+        continue;
+
+      for (i = 0; i < vector_active (old->to); i++)
+        {
+          struct graph_node *cold = vector_slot (old->to, i);
+          if (cold == old_skip)
+            continue;
+
+          if (cmd_nodes_equal (cold, cnew))
+            {
+              struct cmd_token *told = cold->data, *tnew = cnew->data;
+
+              if (told->type == END_TKN)
+                {
+                  if (direction < 0)
+                    {
+                      graph_delete_node (oldgraph, vector_slot (cold->to, 0));
+                      graph_delete_node (oldgraph, cold);
+                    }
+                  else
+                    /* force no-match handling to install END_TKN */
+                    i = vector_active (old->to);
+                  break;
+                }
+
+              /* the entire fork compared as equal, we continue after it. */
+              if (told->type == FORK_TKN)
+                {
+                  if (tnew->attr < told->attr && direction > 0)
+                    cmd_fork_bump_attr (cold, told->forkjoin, tnew->attr);
+                  /* XXX: no reverse bump on uninstall */
+                  told = (cold = told->forkjoin)->data;
+                  tnew = (cnew = tnew->forkjoin)->data;
+                }
+              if (tnew->attr < told->attr)
+                told->attr = tnew->attr;
+
+              cmd_merge_nodes (oldgraph, newgraph, cold, cnew, direction);
+              break;
+            }
+        }
+      /* nothing found => add new to old */
+      if (i == vector_active (old->to) && direction > 0)
+        {
+          assert (vector_count (cnew->from) ==
+                          cmd_nodes_link (cnew, cnew) ? 2 : 1);
+          graph_remove_edge (new, cnew);
+
+          cmd_reparent_tree (newgraph, oldgraph, cnew);
+
+          graph_add_edge (old, cnew);
+        }
+    }
+
+  if (!tok->refcnt)
+    cmd_free_node (oldgraph, old);
+}
+
+void
+cmd_merge_graphs (struct graph *old, struct graph *new, int direction)
+{
+  assert (vector_active (old->nodes) >= 1);
+  assert (vector_active (new->nodes) >= 1);
+
+  cmd_merge_nodes (old, new,
+                   vector_slot (old->nodes, 0), vector_slot (new->nodes, 0),
+                   direction);
+}
+
 /* Install a command into a node. */
 void
 install_element (enum node_type ntype, struct cmd_element *cmd)
@@ -337,13 +603,65 @@ install_element (enum node_type ntype, struct cmd_element *cmd)
 
   assert (hash_get (cnode->cmd_hash, cmd, hash_alloc_intern));
 
-  command_parse_format (cnode->cmdgraph, cmd);
+  struct graph *graph = graph_new();
+  struct cmd_token *token = new_cmd_token (START_TKN, CMD_ATTR_NORMAL, NULL, NULL);
+  graph_new_node (graph, token, (void (*)(void *)) &del_cmd_token);
+
+  command_parse_format (graph, cmd);
+  cmd_merge_graphs (cnode->cmdgraph, graph, +1);
+  graph_delete_graph (graph);
+
   vector_set (cnode->cmd_vector, cmd);
 
   if (ntype == VIEW_NODE)
     install_element (ENABLE_NODE, cmd);
 }
 
+void
+uninstall_element (enum node_type ntype, struct cmd_element *cmd)
+{
+  struct cmd_node *cnode;
+
+  /* cmd_init hasn't been called */
+  if (!cmdvec)
+    {
+      fprintf (stderr, "%s called before cmd_init, breakage likely\n",
+               __func__);
+      return;
+    }
+
+  cnode = vector_slot (cmdvec, ntype);
+
+  if (cnode == NULL)
+    {
+      fprintf (stderr, "Command node %d doesn't exist, please check it\n",
+               ntype);
+      exit (EXIT_FAILURE);
+    }
+
+  if (hash_release (cnode->cmd_hash, cmd) == NULL)
+    {
+      fprintf (stderr,
+               "Trying to uninstall non-installed command (node %d):\n%s\n",
+               ntype, cmd->string);
+      return;
+    }
+
+  vector_unset_value (cnode->cmd_vector, cmd);
+
+  struct graph *graph = graph_new();
+  struct cmd_token *token = new_cmd_token (START_TKN, CMD_ATTR_NORMAL, NULL, NULL);
+  graph_new_node (graph, token, (void (*)(void *)) &del_cmd_token);
+
+  command_parse_format (graph, cmd);
+  cmd_merge_graphs (cnode->cmdgraph, graph, -1);
+  graph_delete_graph (graph);
+
+  if (ntype == VIEW_NODE)
+    uninstall_element (ENABLE_NODE, cmd);
+}
+
+
 static const unsigned char itoa64[] =
 "./0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz";
 
@@ -2420,6 +2738,7 @@ new_cmd_token (enum cmd_token_type type, u_char attr,
   token->attr = attr;
   token->text = text ? XSTRDUP (MTYPE_CMD_TEXT, text) : NULL;
   token->desc = desc ? XSTRDUP (MTYPE_CMD_DESC, desc) : NULL;
+  token->refcnt = 1;
   token->arg  = NULL;
   token->allowrepeat = false;
 
diff --git a/lib/command.h b/lib/command.h
index 04bba9e412..29283418ce 100644
--- a/lib/command.h
+++ b/lib/command.h
@@ -200,6 +200,7 @@ struct cmd_token
   enum cmd_token_type type;     // token type
   u_char attr;                  // token attributes
   bool allowrepeat;             // matcher allowed to match token repetively?
+  uint32_t refcnt;
 
   char *text;                   // token text
   char *desc;                   // token description
@@ -219,6 +220,8 @@ struct cmd_element
 
   /* handler function for command */
   int (*func) (const struct cmd_element *, struct vty *, int, struct cmd_token *[]);
+
+  const char *name;             /* symbol name for debugging */
 };
 
 /* Return value of the commands. */
@@ -251,6 +254,7 @@ struct cmd_element
     .doc = helpstr, \
     .attr = attrs, \
     .daemon = dnum, \
+    .name = #cmdname, \
   };
 
 #define DEFUN_CMD_FUNC_DECL(funcname) \
@@ -402,6 +406,10 @@ extern void install_node (struct cmd_node *, int (*) (struct vty *));
 extern void install_default (enum node_type);
 extern void install_element (enum node_type, struct cmd_element *);
 
+/* known issue with uninstall_element:  changes to cmd_token->attr (i.e.
+ * deprecated/hidden) are not reversed. */
+extern void uninstall_element (enum node_type, struct cmd_element *);
+
 /* Concatenates argv[shift] through argv[argc-1] into a single NUL-terminated
    string with a space between each element (allocated using
    XMALLOC(MTYPE_TMP)).  Returns NULL if shift >= argc. */
@@ -435,6 +443,7 @@ extern void del_cmd_token (struct cmd_token *);
 extern struct cmd_token *copy_cmd_token (struct cmd_token *);
 
 extern vector completions_to_vec (struct list *completions);
+extern void cmd_merge_graphs (struct graph *old, struct graph *new, int direction);
 extern void command_parse_format (struct graph *graph, struct cmd_element *cmd);
 
 /* Export typical functions. */
diff --git a/lib/command_parse.y b/lib/command_parse.y
index 1c220b6b69..0c415af3aa 100644
--- a/lib/command_parse.y
+++ b/lib/command_parse.y
@@ -121,15 +121,6 @@
   doc_next (struct parser_ctx *ctx);
 
   static struct graph_node *
-  node_adjacent (struct graph_node *, struct graph_node *);
-
-  static struct graph_node *
-  add_edge_dedup (struct graph_node *, struct graph_node *);
-
-  static int
-  cmp_token (struct cmd_token *, struct cmd_token *);
-
-  static struct graph_node *
   new_token_node (struct parser_ctx *,
                   enum cmd_token_type type,
                   const char *text,
@@ -179,14 +170,14 @@ start:
 }
 | cmd_token_seq placeholder_token '.' '.' '.'
 {
-  if ((ctx->currnode = add_edge_dedup (ctx->currnode, $2)) != $2)
+  if ((ctx->currnode = graph_add_edge (ctx->currnode, $2)) != $2)
     graph_delete_node (ctx->graph, $2);
 
   ((struct cmd_token *)ctx->currnode->data)->allowrepeat = 1;
 
   // adding a node as a child of itself accepts any number
   // of the same token, which is what we want for variadics
-  add_edge_dedup (ctx->currnode, ctx->currnode);
+  graph_add_edge (ctx->currnode, ctx->currnode);
 
   // tack on the command element
   terminate_graph (&@1, ctx, ctx->currnode);
@@ -201,7 +192,7 @@ cmd_token_seq:
 cmd_token:
   simple_token
 {
-  if ((ctx->currnode = add_edge_dedup (ctx->currnode, $1)) != $1)
+  if ((ctx->currnode = graph_add_edge (ctx->currnode, $1)) != $1)
     graph_delete_node (ctx->graph, $1);
 }
 | selector
@@ -418,9 +409,6 @@ terminate_graph (CMD_YYLTYPE *locp, struct parser_ctx *ctx,
   struct graph_node *end_element_node =
     graph_new_node (ctx->graph, element, NULL);
 
-  if (node_adjacent (finalnode, end_token_node))
-    cmd_yyerror (locp, ctx, "Duplicate command.");
-
   graph_add_edge (finalnode, end_token_node);
   graph_add_edge (end_token_node, end_element_node);
 }
@@ -445,96 +433,3 @@ new_token_node (struct parser_ctx *ctx, enum cmd_token_type type,
   struct cmd_token *token = new_cmd_token (type, ctx->el->attr, text, doc);
   return graph_new_node (ctx->graph, token, (void (*)(void *)) &del_cmd_token);
 }
-
-/**
- * Determines if there is an out edge from the first node to the second
- */
-static struct graph_node *
-node_adjacent (struct graph_node *first, struct graph_node *second)
-{
-  struct graph_node *adj;
-  for (unsigned int i = 0; i < vector_active (first->to); i++)
-    {
-      adj = vector_slot (first->to, i);
-      struct cmd_token *ftok = adj->data,
-                         *stok = second->data;
-      if (cmp_token (ftok, stok))
-        return adj;
-    }
-  return NULL;
-}
-
-/**
- * Creates an edge betwen two nodes, unless there is already an edge to an
- * equivalent node.
- *
- * The first node's out edges are searched to see if any of them point to a
- * node that is equivalent to the second node. If such a node exists, it is
- * returned. Otherwise an edge is created from the first node to the second.
- *
- * @param from start node for edge
- * @param to end node for edge
- * @return the node which the new edge points to
- */
-static struct graph_node *
-add_edge_dedup (struct graph_node *from, struct graph_node *to)
-{
-  struct graph_node *existing = node_adjacent (from, to);
-  if (existing)
-  {
-    struct cmd_token *ex_tok = existing->data;
-    struct cmd_token *to_tok = to->data;
-    // NORMAL takes precedence over DEPRECATED takes precedence over HIDDEN
-    ex_tok->attr = (ex_tok->attr < to_tok->attr) ? ex_tok->attr : to_tok->attr;
-    return existing;
-  }
-  else
-    return graph_add_edge (from, to);
-}
-
-/**
- * Compares two cmd_token's for equality,
- *
- * As such, this function is the working definition of token equality
- * for parsing purposes and determines overall graph structure.
- */
-static int
-cmp_token (struct cmd_token *first, struct cmd_token *second)
-{
-  // compare types
-  if (first->type != second->type) return 0;
-
-  switch (first->type) {
-    case WORD_TKN:
-    case VARIABLE_TKN:
-      if (first->text && second->text)
-        {
-          if (strcmp (first->text, second->text))
-            return 0;
-        }
-      else if (first->text != second->text) return 0;
-      break;
-    case RANGE_TKN:
-      if (first->min != second->min || first->max != second->max)
-        return 0;
-      break;
-    /* selectors and options should be equal if their subgraphs are equal,
-     * but the graph isomorphism problem is not known to be solvable in
-     * polynomial time so we consider selectors and options inequal in all
-     * cases; ultimately this forks the graph, but the matcher can handle
-     * this regardless
-     */
-    case FORK_TKN:
-      return 0;
-
-    /* end nodes are always considered equal, since each node may only
-     * have one END_TKN child at a time
-     */
-    case START_TKN:
-    case END_TKN:
-    case JOIN_TKN:
-    default:
-      break;
-  }
-  return 1;
-}
diff --git a/lib/grammar_sandbox.c b/lib/grammar_sandbox.c
index 08f012f8ac..e3a7c979fc 100644
--- a/lib/grammar_sandbox.c
+++ b/lib/grammar_sandbox.c
@@ -27,6 +27,7 @@
 #include "command.h"
 #include "memory_vty.h"
 #include "graph.h"
+#include "linklist.h"
 #include "command_match.h"
 
 #define GRAMMAR_STR "CLI grammar sandbox\n"
@@ -68,7 +69,12 @@ DEFUN (grammar_test,
   cmd->func = NULL;
 
   // parse the command and install it into the command graph
-  command_parse_format (nodegraph, cmd);
+  struct graph *graph = graph_new();
+  struct cmd_token *token = new_cmd_token (START_TKN, CMD_ATTR_NORMAL, NULL, NULL);
+  graph_new_node (graph, token, (void (*)(void *)) &del_cmd_token);
+
+  command_parse_format (graph, cmd);
+  cmd_merge_graphs (nodegraph, graph, +1);
 
   return CMD_SUCCESS;
 }
@@ -277,6 +283,157 @@ DEFUN (grammar_test_dot,
   return CMD_SUCCESS;
 }
 
+struct cmd_permute_item
+{
+  char *cmd;
+  struct cmd_element *el;
+};
+
+static void
+cmd_permute_free (void *arg)
+{
+  struct cmd_permute_item *i = arg;
+  XFREE (MTYPE_TMP, i->cmd);
+  XFREE (MTYPE_TMP, i);
+}
+
+static int
+cmd_permute_cmp (void *a, void *b)
+{
+  struct cmd_permute_item *aa = a, *bb = b;
+  return strcmp (aa->cmd, bb->cmd);
+}
+
+static void
+cmd_graph_permute (struct list *out, struct graph_node **stack,
+                   size_t stackpos, char *cmd)
+{
+  struct graph_node *gn = stack[stackpos];
+  struct cmd_token *tok = gn->data;
+  char *appendp = cmd + strlen(cmd);
+  size_t i, j;
+
+  if (tok->type < SPECIAL_TKN)
+    {
+      sprintf (appendp, "%s ", tok->text);
+      appendp += strlen (appendp);
+    }
+  else if (tok->type == END_TKN)
+    {
+      struct cmd_permute_item *i = XMALLOC (MTYPE_TMP, sizeof (*i));
+      i->el = ((struct graph_node *)vector_slot (gn->to, 0))->data;
+      i->cmd = XSTRDUP (MTYPE_TMP, cmd);
+      i->cmd[strlen(cmd) - 1] = '\0';
+      listnode_add_sort (out, i);
+      return;
+    }
+
+  if (++stackpos == MAXDEPTH)
+    return;
+
+  for (i = 0; i < vector_active (gn->to); i++)
+    {
+      struct graph_node *gnext = vector_slot (gn->to, i);
+      for (j = 0; j < stackpos; j++)
+        if (stack[j] == gnext)
+          break;
+      if (j != stackpos)
+        continue;
+
+      stack[stackpos] = gnext;
+      *appendp = '\0';
+      cmd_graph_permute (out, stack, stackpos, cmd);
+    }
+}
+
+static struct list *
+cmd_graph_permutations (struct graph *graph)
+{
+  char accumulate[2048] = "";
+  struct graph_node *stack[MAXDEPTH];
+
+  struct list *rv = list_new ();
+  rv->cmp = cmd_permute_cmp;
+  rv->del = cmd_permute_free;
+  stack[0] = vector_slot (graph->nodes, 0);
+  cmd_graph_permute (rv, stack, 0, accumulate);
+  return rv;
+}
+
+extern vector cmdvec;
+
+DEFUN (grammar_findambig,
+       grammar_findambig_cmd,
+       "grammar find-ambiguous [{printall|nodescan}]",
+       GRAMMAR_STR
+       "Find ambiguous commands\n"
+       "Print all permutations\n"
+       "Scan all nodes\n")
+{
+  struct list *commands;
+  struct cmd_permute_item *prev = NULL, *cur = NULL;
+  struct listnode *ln;
+  int i, printall, scan, scannode = 0;
+  int ambig = 0;
+
+  i = 0;
+  printall = argv_find (argv, argc, "printall", &i);
+  i = 0;
+  scan = argv_find (argv, argc, "nodescan", &i);
+
+  if (scan && nodegraph_free)
+    {
+      graph_delete_graph (nodegraph_free);
+      nodegraph_free = NULL;
+    }
+
+  if (!scan && !nodegraph)
+    {
+      vty_out(vty, "nodegraph uninitialized\r\n");
+      return CMD_WARNING;
+    }
+
+  do {
+    if (scan)
+      {
+        struct cmd_node *cnode = vector_slot (cmdvec, scannode++);
+        if (!cnode)
+          continue;
+        nodegraph = cnode->cmdgraph;
+        if (!nodegraph)
+          continue;
+        vty_out (vty, "scanning node %d%s", scannode - 1, VTY_NEWLINE);
+      }
+
+    commands = cmd_graph_permutations (nodegraph);
+    prev = NULL;
+    for (ALL_LIST_ELEMENTS_RO (commands, ln, cur))
+      {
+        int same = prev && !strcmp (prev->cmd, cur->cmd);
+        if (printall && !same)
+          vty_out (vty, "'%s'%s", cur->cmd, VTY_NEWLINE);
+        if (same)
+          {
+            vty_out (vty, "'%s' AMBIGUOUS:%s", cur->cmd, VTY_NEWLINE);
+            vty_out (vty, "  %s%s   '%s'%s", prev->el->name, VTY_NEWLINE, prev->el->string, VTY_NEWLINE);
+            vty_out (vty, "  %s%s   '%s'%s", cur->el->name,  VTY_NEWLINE, cur->el->string,  VTY_NEWLINE);
+            vty_out (vty, "%s", VTY_NEWLINE);
+            ambig++;
+          }
+        prev = cur;
+      }
+    list_delete (commands);
+
+    vty_out (vty, "%s", VTY_NEWLINE);
+  } while (scan && scannode < LINK_PARAMS_NODE);
+
+  vty_out (vty, "%d ambiguous commands found.%s", ambig, VTY_NEWLINE);
+
+  if (scan)
+    nodegraph = NULL;
+  return ambig == 0 ? CMD_SUCCESS : CMD_WARNING;
+}
+
 DEFUN (grammar_init_graph,
        grammar_init_graph_cmd,
        "grammar init",
@@ -291,8 +448,6 @@ DEFUN (grammar_init_graph,
   return CMD_SUCCESS;
 }
 
-extern vector cmdvec;
-
 DEFUN (grammar_access,
        grammar_access_cmd,
        "grammar access (0-65535)",
@@ -329,6 +484,7 @@ void grammar_sandbox_init(void) {
   install_element (ENABLE_NODE, &grammar_test_match_cmd);
   install_element (ENABLE_NODE, &grammar_test_complete_cmd);
   install_element (ENABLE_NODE, &grammar_test_doc_cmd);
+  install_element (ENABLE_NODE, &grammar_findambig_cmd);
   install_element (ENABLE_NODE, &grammar_init_graph_cmd);
   install_element (ENABLE_NODE, &grammar_access_cmd);
 }
diff --git a/ospf6d/ospf6_asbr.c b/ospf6d/ospf6_asbr.c
index 643519e3fa..5f2d662b78 100644
--- a/ospf6d/ospf6_asbr.c
+++ b/ospf6d/ospf6_asbr.c
@@ -1114,7 +1114,7 @@ DEFUN (ospf6_routemap_set_metric_type,
 /* delete "set metric-type" */
 DEFUN (ospf6_routemap_no_set_metric_type,
        ospf6_routemap_no_set_metric_type_cmd,
-       "no set metric-type <type-1|type-2>",
+       "no set metric-type [<type-1|type-2>]",
        NO_STR
        "Set value\n"
        "Type of metric\n"
@@ -1122,9 +1122,9 @@ DEFUN (ospf6_routemap_no_set_metric_type,
        "OSPF6 external type 2 metric\n")
 {
   VTY_DECLVAR_CONTEXT(route_map_index, route_map_index);
-  int idx_external = 3;
-  int ret = route_map_delete_set (route_map_index, 
-                                  "metric-type", argv[idx_external]->arg);
+  char *ext = (argc == 4) ? argv[3]->text : NULL;
+  int ret = route_map_delete_set (route_map_index,
+                                  "metric-type", ext);
   return route_map_command_status (vty, ret);
 }
 
diff --git a/pimd/pim_cmd.c b/pimd/pim_cmd.c
index ae23499d97..62d8ad8e07 100644
--- a/pimd/pim_cmd.c
+++ b/pimd/pim_cmd.c
@@ -5964,7 +5964,7 @@ ip_msdp_show_sa_sg(struct vty *vty, const char *src, const char *grp, u_char uj)
 
 DEFUN (show_ip_msdp_sa_sg,
        show_ip_msdp_sa_sg_cmd,
-       "show ip msdp sa [A.B.C.D] [A.B.C.D] [json]",
+       "show ip msdp sa [A.B.C.D [A.B.C.D]] [json]",
        SHOW_STR
        IP_STR
        MSDP_STR
diff --git a/tests/lib/cli/common_cli.c b/tests/lib/cli/common_cli.c
index 83196e04aa..104352f516 100644
--- a/tests/lib/cli/common_cli.c
+++ b/tests/lib/cli/common_cli.c
@@ -83,7 +83,7 @@ main (int argc, char **argv)
   vty_init (master);
   memory_init ();
 
-  test_init ();
+  test_init (argc, argv);
 
   vty_stdio (vty_do_exit);
 
diff --git a/tests/lib/cli/common_cli.h b/tests/lib/cli/common_cli.h
index 9c72b08e44..9e7fe99830 100644
--- a/tests/lib/cli/common_cli.h
+++ b/tests/lib/cli/common_cli.h
@@ -28,7 +28,7 @@
 #include "command.h"
 
 /* function to be implemented by test */
-extern void test_init (void);
+extern void test_init (int argc, char **argv);
 
 /* functions provided by common cli
  * (includes main())
diff --git a/tests/lib/cli/test_cli.c b/tests/lib/cli/test_cli.c
index 1a316022e2..54b34bc799 100644
--- a/tests/lib/cli/test_cli.c
+++ b/tests/lib/cli/test_cli.c
@@ -38,8 +38,10 @@ DUMMY_DEFUN(cmd11, "alt a WORD");
 DUMMY_DEFUN(cmd12, "alt a A.B.C.D");
 DUMMY_DEFUN(cmd13, "alt a X:X::X:X");
 
-void test_init(void)
+void test_init(int argc, char **argv)
 {
+  size_t repeat = argc > 1 ? strtoul(argv[1], NULL, 0) : 223;
+
   install_element (ENABLE_NODE, &cmd0_cmd);
   install_element (ENABLE_NODE, &cmd1_cmd);
   install_element (ENABLE_NODE, &cmd2_cmd);
@@ -53,4 +55,12 @@ void test_init(void)
   install_element (ENABLE_NODE, &cmd11_cmd);
   install_element (ENABLE_NODE, &cmd12_cmd);
   install_element (ENABLE_NODE, &cmd13_cmd);
+  for (size_t i = 0; i < repeat; i++) {
+    uninstall_element (ENABLE_NODE, &cmd5_cmd);
+    install_element (ENABLE_NODE, &cmd5_cmd);
+  }
+  for (size_t i = 0; i < repeat; i++) {
+    uninstall_element (ENABLE_NODE, &cmd13_cmd);
+    install_element (ENABLE_NODE, &cmd13_cmd);
+  }
 }
diff --git a/vtysh/vtysh_main.c b/vtysh/vtysh_main.c
index 49aedae322..561eda0454 100644
--- a/vtysh/vtysh_main.c
+++ b/vtysh/vtysh_main.c
@@ -274,7 +274,7 @@ main (int argc, char **argv, char **env)
   const char *inputfile = NULL;
   const char *vtysh_configfile_name;
   struct cmd_rec {
-    const char *line;
+    char *line;
     struct cmd_rec *next;
   } *cmd = NULL;
   struct cmd_rec *tail = NULL;
@@ -444,7 +444,7 @@ main (int argc, char **argv, char **env)
     }
 
   /* Start execution only if not in dry-run mode */
-  if(dryrun)
+  if (dryrun && !cmd)
     {
       if (inputfile)
 	{
@@ -454,6 +454,39 @@ main (int argc, char **argv, char **env)
 	{
 	  ret = vtysh_read_config(quagga_config_default);
 	}
+
+      exit(ret);
+    }
+
+  if (dryrun && cmd)
+    {
+      vtysh_execute ("enable");
+      while (cmd)
+        {
+          struct cmd_rec *cr;
+          char *cmdnow = cmd->line, *next;
+          do
+            {
+              next = strchr(cmdnow, '\n');
+              if (next)
+                *next++ = '\0';
+
+              if (echo_command)
+                printf("%s%s\n", vtysh_prompt(), cmdnow);
+
+              ret = vtysh_execute_no_pager(cmdnow);
+              if (!no_error &&
+                  ! (ret == CMD_SUCCESS ||
+                     ret == CMD_SUCCESS_DAEMON ||
+                     ret == CMD_WARNING))
+                exit(1);
+            }
+          while ((cmdnow = next) != NULL);
+
+          cr = cmd;
+          cmd = cmd->next;
+          XFREE(MTYPE_TMP, cr);
+        }
       exit(ret);
     }
 
diff --git a/zebra/zebra_mpls_vty.c b/zebra/zebra_mpls_vty.c
index fcd0fff32c..dd381723c5 100644
--- a/zebra/zebra_mpls_vty.c
+++ b/zebra/zebra_mpls_vty.c
@@ -472,7 +472,7 @@ DEFUN (no_ip_route_tag_distance_label,
 
 DEFUN (no_ip_route_mask_distance_label,
        no_ip_route_mask_distance_label_cmd,
-       "no ip route A.B.C.D A.B.C.D <A.B.C.D|INTERFACE|null0> (1-255)",
+       "no ip route A.B.C.D A.B.C.D <A.B.C.D|INTERFACE|null0> (1-255) label WORD",
        NO_STR
        IP_STR
        "Establish static routes\n"
@@ -486,7 +486,7 @@ DEFUN (no_ip_route_mask_distance_label,
        "One or more labels separated by '/'\n")
 {
   return zebra_static_ipv4 (vty, SAFI_UNICAST, 0, argv[3]->arg, argv[4]->arg, argv[5]->arg, NULL, NULL,
-                            argv[6]->arg, NULL, NULL);
+                            argv[6]->arg, NULL, argv[8]->arg);
 }
 
 DEFUN (no_ip_route_mask_tag_distance_label,