tools/permutations.c

   1 /*
   2  * Generates all possible matching inputs for a command string.
   3  * --
   4  * Copyright (C) 2016 Cumulus Networks, Inc.
   5  *
   6  * This file is part of GNU Zebra.
   7  *
   8  * GNU Zebra is free software; you can redistribute it and/or modify it
   9  * under the terms of the GNU General Public License as published by the
  10  * Free Software Foundation; either version 2, or (at your option) any
  11  * later version.
  12  *
  13  * GNU Zebra is distributed in the hope that it will be useful, but
  14  * WITHOUT ANY WARRANTY; without even the implied warranty of
  15  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  16  * General Public License for more details.
  17  *
  18  * You should have received a copy of the GNU General Public License along
  19  * with this program; see the file COPYING; if not, write to the Free Software
  20  * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
  21  */
  22
  23 #include "command.h"
  24 #include "graph.h"
  25 #include "vector.h"
  26
  27 #define USAGE "usage: permutations <cmdstr>"
  28
  29 void permute(struct graph_node *);
  30 void pretty_print_graph(struct graph_node *start, int level);
  31
  32 int main(int argc, char *argv[])
  33 {
  34         if (argc < 2) {
  35                 fprintf(stdout, USAGE "\n");
  36                 exit(EXIT_SUCCESS);
  37         }
  38         struct cmd_element *cmd = calloc(1, sizeof(struct cmd_element));
  39         cmd->string = strdup(argv[1]);
  40
  41         struct graph *graph = graph_new();
  42         struct cmd_token *token =
  43                 cmd_token_new(START_TKN, cmd->attr, NULL, NULL);
  44         graph_new_node(graph, token, NULL);
  45         cmd_graph_parse(graph, cmd);
  46
  47         permute(vector_slot(graph->nodes, 0));
  48 }
  49
  50 void permute(struct graph_node *start)
  51 {
  52         static struct list *position = NULL;
  53         if (!position)
  54                 position = list_new();
  55
  56         struct cmd_token *stok = start->data;
  57         struct graph_node *gnn;
  58         struct listnode *ln;
  59
  60         // recursive dfs
  61         listnode_add(position, start);
  62         for (unsigned int i = 0; i < vector_active(start->to); i++) {
  63                 struct graph_node *gn = vector_slot(start->to, i);
  64                 struct cmd_token *tok = gn->data;
  65                 if (tok->attr == CMD_ATTR_HIDDEN
  66                     || tok->attr == CMD_ATTR_DEPRECATED)
  67                         continue;
  68                 else if (tok->type == END_TKN || gn == start) {
  69                         fprintf(stdout, " ");
  70                         for (ALL_LIST_ELEMENTS_RO(position, ln, gnn)) {
  71                                 struct cmd_token *tt = gnn->data;
  72                                 if (tt->type < SPECIAL_TKN)
  73                                         fprintf(stdout, " %s", tt->text);
  74                         }
  75                         if (gn == start)
  76                                 fprintf(stdout, "...");
  77                         fprintf(stdout, "\n");
  78                 } else {
  79                         bool skip = false;
  80                         if (stok->type == FORK_TKN && tok->type != FORK_TKN)
  81                                 for (ALL_LIST_ELEMENTS_RO(position, ln, gnn))
  82                                         if (gnn == gn) {
  83                                                 skip = true;
  84                                                 break;
  85                                         }
  86                         if (!skip)
  87                                 permute(gn);
  88                 }
  89         }
  90         list_delete_node(position, listtail(position));
  91 }