#define ALLOWED_LITERALS "0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz"
+/**
+ * Transition between two states. Each state can have 0-n transitions. If label
+ * is 0, this is considered to be an epsilon transition.
+ */
+struct GNUNET_REGEX_Transition
+{
+ /**
+ * This is a linked list.
+ */
+ struct GNUNET_REGEX_Transition *prev;
+
+ /**
+ * This is a linked list.
+ */
+ struct GNUNET_REGEX_Transition *next;
+
+ /**
+ * Unique id of this transition.
+ */
+ unsigned int id;
+
+ /**
+ * Label for this transition. This is basically the edge label for the graph.
+ */
+ char *label;
+
+ /**
+ * State to which this transition leads.
+ */
+ struct GNUNET_REGEX_State *to_state;
+
+ /**
+ * State from which this transition origins.
+ */
+ struct GNUNET_REGEX_State *from_state;
+};
+
+
+/**
+ * A state. Can be used in DFA and NFA automatons.
+ */
+struct GNUNET_REGEX_State
+{
+ /**
+ * This is a linked list.
+ */
+ struct GNUNET_REGEX_State *prev;
+
+ /**
+ * This is a linked list.
+ */
+ struct GNUNET_REGEX_State *next;
+
+ /**
+ * Unique state id.
+ */
+ unsigned int id;
+
+ /**
+ * Unique state id that is used for traversing the automaton. It is guaranteed
+ * to be > 0 and < state_count.
+ */
+ unsigned int traversal_id;
+
+ /**
+ * If this is an accepting state or not.
+ */
+ int accepting;
+
+ /**
+ * Marking of the state. This is used for marking all visited states when
+ * traversing all states of an automaton and for cases where the state id
+ * cannot be used (dfa minimization).
+ */
+ int marked;
+
+ /**
+ * Marking the state as contained. This is used for checking, if the state is
+ * contained in a set in constant time
+ */
+ int contained;
+
+ /**
+ * Marking the state as part of an SCC (Strongly Connected Component). All
+ * states with the same scc_id are part of the same SCC. scc_id is 0, if state
+ * is not a part of any SCC.
+ */
+ unsigned int scc_id;
+
+ /**
+ * Used for SCC detection.
+ */
+ int index;
+
+ /**
+ * Used for SCC detection.
+ */
+ int lowlink;
+
+ /**
+ * Human readable name of the automaton. Used for debugging and graph
+ * creation.
+ */
+ char *name;
+
+ /**
+ * Hash of the state.
+ */
+ struct GNUNET_HashCode hash;
+
+ /**
+ * Linear state ID accquired by depth-first-search. This ID should be used for
+ * storing information about the state in an array, because the 'id' of the
+ * state is not guaranteed to be linear. The 'dfs_id' is guaranteed to be > 0
+ * and < 'state_count'.
+ */
+ unsigned int dfs_id;
+
+ /**
+ * Proof for this state.
+ */
+ char *proof;
+
+ /**
+ * Number of transitions from this state to other states.
+ */
+ unsigned int transition_count;
+
+ /**
+ * DLL of transitions.
+ */
+ struct GNUNET_REGEX_Transition *transitions_head;
+
+ /**
+ * DLL of transitions.
+ */
+ struct GNUNET_REGEX_Transition *transitions_tail;
+
+ /**
+ * Set of states on which this state is based on. Used when creating a DFA out
+ * of several NFA states.
+ */
+ struct GNUNET_REGEX_StateSet *nfa_set;
+};
+
+
+/**
+ * Type of an automaton.
+ */
+enum GNUNET_REGEX_AutomatonType
+{
+ NFA,
+ DFA
+};
+
+
+/**
+ * Automaton representation.
+ */
+struct GNUNET_REGEX_Automaton
+{
+ /**
+ * Linked list of NFAs used for partial NFA creation.
+ */
+ struct GNUNET_REGEX_Automaton *prev;
+
+ /**
+ * Linked list of NFAs used for partial NFA creation.
+ */
+ struct GNUNET_REGEX_Automaton *next;
+
+ /**
+ * First state of the automaton. This is mainly used for constructing an NFA,
+ * where each NFA itself consists of one or more NFAs linked together.
+ */
+ struct GNUNET_REGEX_State *start;
+
+ /**
+ * End state of the partial NFA. This is undefined for DFAs
+ */
+ struct GNUNET_REGEX_State *end;
+
+ /**
+ * Number of states in the automaton.
+ */
+ unsigned int state_count;
+
+ /**
+ * DLL of states.
+ */
+ struct GNUNET_REGEX_State *states_head;
+
+ /**
+ * DLL of states
+ */
+ struct GNUNET_REGEX_State *states_tail;
+
+ /**
+ * Type of the automaton.
+ */
+ enum GNUNET_REGEX_AutomatonType type;
+
+ /**
+ * Regex
+ */
+ char *regex;
+
+ /**
+ * Canonical regex (result of RX->NFA->DFA->RX)
+ */
+ char *canonical_regex;
+};
+
+
+/**
+ * Function that is called with each state, when traversing an automaton.
+ *
+ * @param cls closure.
+ * @param count current count of the state, from 0 to a->state_count -1.
+ * @param s state.
+ */
+typedef void (*GNUNET_REGEX_traverse_action) (void *cls,
+ const unsigned int count,
+ struct GNUNET_REGEX_State * s);
+
+
+/**
+ * Traverses the given automaton using depth-first-search (DFS) from it's start
+ * state, visiting all reachable states and calling 'action' on each one of
+ * them.
+ *
+ * @param a automaton to be traversed.
+ * @param start start state, pass a->start or NULL to traverse the whole automaton.
+ * @param action action to be performed on each state.
+ * @param action_cls closure for action
+ */
+void
+GNUNET_REGEX_automaton_traverse (const struct GNUNET_REGEX_Automaton *a,
+ struct GNUNET_REGEX_State *start,
+ GNUNET_REGEX_traverse_action action,
+ void *action_cls);
+
+
/**
* Get the canonical regex of the given automaton.
* When constructing the automaton a proof is computed for each state,
char *
GNUNET_REGEX_generate_random_string (size_t max_len);
+
#if 0 /* keep Emacsens' auto-indent happy */
{
#endif
projects / oweals / gnunet.git / blobdiff