Move procedure for running NFA into FSA module

lib/fsa.c

@@ -65,3 +65,24 @@ void fsa_add_rule(fsa_t *fsa, int from, int to, int input)
 	rule->next = to;
 	++state->count;
 }
+
+bool fsa_accepts(const fsa_t *dfa, const char *input, int len)
+{
+	const char *end = input + len;
+	int current = dfa->initial;
+	while (input < end) {
+		bool found = false;
+		const fsa_rule_t *rules = dfa->states[current].rules;
+		for (int i = 0; i < dfa->states[current].count; ++i) {
+			if (rules[i].input == *input) {
+				current = rules[i].next;
+				found = true;
+				break;
+			}
+		}
+		if (!found)
+			return false;
+		++input;
+	}
+	return dfa->states[current].final;
+}

lib/include/fsa.h

@@ -35,4 +35,6 @@ void fsa_free(const fsa_t *fsa);
 int fsa_add_state(fsa_t *fsa);
 void fsa_add_rule(fsa_t *fsa, int from, int to, int input);
 
+bool fsa_accepts(const fsa_t *dfa, const char *input, int len);
+
 #endif