lib/command_graph.h

   1 #ifndef COMMAND_GRAPH_H
   2 #define COMMAND_GRAPH_H
   3
   4 #include "command.h"
   5
   6 enum graph_node_type
   7 {
   8   IPV4_GN,
   9   IPV4_PREFIX_GN,
  10   IPV6_GN,
  11   IPV6_PREFIX_GN,
  12   WORD_GN,
  13   RANGE_GN,
  14   NUMBER_GN,
  15   VARIABLE_GN,
  16   SELECTOR_GN,
  17   OPTION_GN,
  18   NUL_GN,
  19   START_GN,
  20   END_GN
  21 };
  22
  23 struct graph_node
  24 {
  25   enum graph_node_type type;// data type this node matches or holds
  26   unsigned int is_start;    // whether this node is a start node
  27   vector children;          // this node's children
  28   struct graph_node * end;  // pointer to end for SELECTOR_GN & OPTION_GN
  29
  30   char *text;               // original format text
  31   char *doc;                // docstring for this node
  32   long long value;          // for NUMBER_GN
  33   long long min, max;       // for RANGE_GN
  34
  35   /* cmd_element struct pointer, only valid for END_GN */
  36   struct cmd_element *element;
  37   /* used for passing arguments to command functions */
  38   char *arg;
  39
  40   /* refcount for node parents */
  41   unsigned int refs;
  42 };
  43
  44 /*
  45  * Adds a node as a child of another node.
  46  *
  47  * @param[in] parent node
  48  * @param[in] child node
  49  * @return child node, for convenience
  50  */
  51 struct graph_node *
  52 add_node(struct graph_node *, struct graph_node *);
  53
  54 /*
  55  * Compares two nodes for parsing equivalence.
  56  * Equivalence in this case means that a single user input token
  57  * should be able to unambiguously match one of the two nodes.
  58  * For example, two nodes which have all fields equal except their
  59  * function pointers would be considered equal.
  60  *
  61  * @param[in] first node to compare
  62  * @param[in] second node to compare
  63  * @return 1 if equal, zero otherwise.
  64  */
  65 int
  66 cmp_node(struct graph_node *, struct graph_node *);
  67
  68 /*
  69  * Create a new node.
  70  * Initializes all fields to default values and sets the node type.
  71  *
  72  * @param[in] node type
  73  * @return pointer to the newly allocated node
  74  */
  75 struct graph_node *
  76 new_node(enum graph_node_type);
  77
  78 /**
  79  * Frees the data associated with a graph_node.
  80  * @param[out] pointer to graph_node to free
  81  */
  82 void
  83 free_node(struct graph_node *);
  84
  85 /**
  86  * Recursively calls free_node on a graph node
  87  * and all its children.
  88  * @param[out] graph to free
  89  */
  90 void
  91 free_graph(struct graph_node *);
  92
  93 /**
  94  * Walks a command DFA, printing structure to stdout.
  95  * For debugging.
  96  *
  97  * @param[in] start node of graph to walk
  98  * @param[in] graph depth for recursion, caller passes 0
  99  */
 100 void
 101 walk_graph(struct graph_node *, int);
 102
 103 /**
 104  * Returns a string representation of the given node.
 105  * @param[in] the node to describe
 106  * @param[out] the buffer to write the description into
 107  * @return pointer to description string
 108  */
 109 char *
 110 describe_node(struct graph_node *, char *, unsigned int);
 111
 112 void
 113 dump_node (struct graph_node *);
 114 #endif