lib/command_graph.h

   1 #ifndef COMMAND_GRAPH_H
   2 #define COMMAND_GRAPH_H
   3
   4 #include "vty.h"
   5 #include "vector.h"
   6
   7 enum graph_node_type
   8 {
   9   WORD_GN,
  10   IPV4_GN,
  11   IPV4_PREFIX_GN,
  12   IPV6_GN,
  13   IPV6_PREFIX_GN,
  14   VARIABLE_GN,
  15   RANGE_GN,
  16   NUMBER_GN,
  17   SELECTOR_GN,
  18   OPTION_GN,
  19   NUL_GN
  20 };
  21
  22 struct graph_node
  23 {
  24   enum graph_node_type type;
  25   vector children;
  26   int is_root;              // true if first token in command
  27   int is_leaf;              // true if last token in command
  28   struct graph_node * end;  // pointer to end for selector & option
  29
  30   int (*func)(struct vty *, int, const char *[]);
  31
  32   /* various data fields for nodes */
  33   char* text;       // for words and variables
  34   int value;        // for numbers
  35   int min, max;     // for ranges
  36 };
  37
  38 /*
  39  * Adds a child to a node.
  40  * If the node already has the exact same child, nothing is done. This is
  41  * decided with cmp_node.
  42  *
  43  * @param[in] parent node
  44  * @param[in] child node
  45  * @return the new child, or the existing child if the parent already has the
  46  *         new child
  47  */
  48 extern struct graph_node *
  49 add_node(struct graph_node *, struct graph_node *);
  50
  51 /*
  52  * Compares two nodes for parsing equivalence.
  53  * Equivalence in this case means that a single user input token
  54  * should be able to unambiguously match one of the two nodes.
  55  * For example, two nodes which have all fields equal except their
  56  * function pointers would be considered equal.
  57  *
  58  * @param[in] first node to compare
  59  * @param[in] second node to compare
  60  * @return 1 if equal, zero otherwise.
  61  */
  62 extern int
  63 cmp_node(struct graph_node *, struct graph_node *);
  64
  65 /*
  66  * Create a new node.
  67  * Initializes all fields to default values and sets the node type.
  68  *
  69  * @param[in] node type
  70  * @return pointer to the newly allocated node
  71  */
  72 extern struct graph_node *
  73 new_node(enum graph_node_type);
  74
  75 /**
  76  * Walks a command DFA, printing structure to stdout.
  77  * For debugging.
  78  *
  79  * @param[in] start node of graph to walk
  80  * @param[in] graph depth for recursion, caller passes 0
  81  */
  82 extern void
  83 walk_graph(struct graph_node *, int);
  84
  85 /**
  86  * Returns a string representation of the given node.
  87  * @param[in] the node to describe
  88  * @return pointer to description string
  89  */
  90 extern const char *
  91 describe_node(struct graph_node *);
  92 #endif