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
  19  * along with GNU Zebra; see the file COPYING.  If not, write to the Free
  20  * Software Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA
  21  * 02111-1307, USA.
  22  */
  23
  24 #include "command.h"
  25 #include "graph.h"
  26 #include "vector.h"
  27
  28 #define USAGE "usage: permutations <cmdstr>"
  29
  30 void permute(struct graph_node *);
  31 void pretty_print_graph(struct graph_node *start, int level);
  32
  33 int main(int argc, char *argv[])
  34 {
  35         if (argc < 2) {
  36                 fprintf(stdout, USAGE "\n");
  37                 exit(EXIT_SUCCESS);
  38         }
  39         struct cmd_element *cmd = calloc(1, sizeof(struct cmd_element));
  40         cmd->string = strdup(argv[1]);
  41
  42         struct graph *graph = graph_new();
  43         struct cmd_token *token =
  44                 new_cmd_token(START_TKN, cmd->attr, NULL, NULL);
  45         graph_new_node(graph, token, NULL);
  46         command_parse_format(graph, cmd);
  47
  48         permute(vector_slot(graph->nodes, 0));
  49 }
  50
  51 void permute(struct graph_node *start)
  52 {
  53         static struct list *position = NULL;
  54         if (!position)
  55                 position = list_new();
  56
  57         struct cmd_token *stok = start->data;
  58         struct graph_node *gnn;
  59         struct listnode *ln;
  60
  61         // recursive dfs
  62         listnode_add(position, start);
  63         for (unsigned int i = 0; i < vector_active(start->to); i++) {
  64                 struct graph_node *gn = vector_slot(start->to, i);
  65                 struct cmd_token *tok = gn->data;
  66                 if (tok->attr == CMD_ATTR_HIDDEN
  67                     || tok->attr == CMD_ATTR_DEPRECATED)
  68                         continue;
  69                 else if (tok->type == END_TKN || gn == start) {
  70                         fprintf(stdout, " ");
  71                         for (ALL_LIST_ELEMENTS_RO(position, ln, gnn)) {
  72                                 struct cmd_token *tt = gnn->data;
  73                                 if (tt->type < SPECIAL_TKN)
  74                                         fprintf(stdout, " %s", tt->text);
  75                         }
  76                         if (gn == start)
  77                                 fprintf(stdout, "...");
  78                         fprintf(stdout, "\n");
  79                 } else {
  80                         bool skip = false;
  81                         if (stok->type == FORK_TKN && tok->type != FORK_TKN)
  82                                 for (ALL_LIST_ELEMENTS_RO(position, ln, gnn))
  83                                         if (gnn == gn) {
  84                                                 skip = true;
  85                                                 break;
  86                                         }
  87                         if (!skip)
  88                                 permute(gn);
  89                 }
  90         }
  91         list_delete_node(position, listtail(position));
  92 }