re.h

/* Copyright (c) 1994 Sun Wu, Udi Manber, Burra Gopal.  All Rights Reserved. */

/*	09.09.96	T.Gries		new definition of ASCII_MAX
					allows the fully ISO-Charset.
*/

/*************************************************************
 *							     *
 * 	Macros defining special characters.		     *
 *							     *
 *************************************************************/

#define NUL	    '\0'
#define ASCII_MIN   '\001'
#define ASCII_MAX   '\377'	/* changed by TG. Orginal value was \177 */

/*************************************************************
 *							     *
 * 	Macros defining lexical categories.		     *
 *							     *
 *************************************************************/

#define C_LIT	0   /* individual character literal */
#define C_SET	1   /* character set literal	    */

#define EOS		0	/* end-of-string */
#define LITERAL		1
#define OPSTAR		2
#define OPALT		3
#define OPOPT		4
#define OPCAT		5
#define LPAREN		6
#define RPAREN		7

/*************************************************************
 *							     *
 * 	Macros for manipulating syntax tree nodes.	     *
 *							     *
 *************************************************************/

#define lit_type(x)	(x->l_type)
#define lit_pos(x)	(x->pos)
#define lit_char(x)	((x->val).c)
#define lit_cset(x)	((x->val).cset)

#define tok_type(x)	(x->type)
#define tok_val(x)	(x->val)
#define tok_op(x)       (x->val->op)
#define tok_lit(x)	((x->val->refs).lit)

#define Op(x)		(x->op)
#define Lit(x)		((x->refs).lit)
#define Child(x)	((x->refs).child)
#define Lchild(x)	((x->refs).children.l_child)
#define Rchild(x)	((x->refs).children.r_child)
#define Nullable(x)	(x->nullable)
#define Firstpos(x)	(x->firstposn)
#define Lastpos(x)	(x->lastposn)

/*************************************************************
 *							     *
 *  Macros for manipulating DFA states and sets of states.   *
 *							     *
 *************************************************************/

#define Positions(x)	(x->posns)
#define Final_St(x)	(x->final)
#define Goto(x, c)	((x->trans)[c])
#define Next_State(x)	((x)->next_state)

/*************************************************************/

#define new_node(type, l, x)	\
{\
	extern void *malloc();\
\
	(l) = (type) malloc(sizeof(*(x)));\
	if ((l) == NULL) {\
		fprintf(stderr, "malloc failure in new_node\n");\
		exit(2);\
	}\
	memset((l), '\0', sizeof(*(x)));\
}

typedef struct {	/* character range literals */
		char low_bd, hi_bd;
	} *Ch_Range;

typedef struct ch_set {	    /* character set literals */
		Ch_Range elt;	/* rep. as list of ranges */
		struct ch_set *rest;
	} *Ch_Set;

typedef struct {	/* regular expression literal */
		int pos;	     /* position in syntax tree */
		short l_type;    /* type of literal */
		union {
		char c;     /* for character literals */
		Ch_Set cset; /* for character sets */
		} val;
	} *Re_Lit, *(*Re_lit_array)[];

typedef struct pnode {
		int posnum;
		struct pnode *nextpos;
	} *Pset, *(*Pset_array)[];

typedef struct rnode {	/* regular expression node */
		short op;     /* operator at that node */
		union {
		Re_Lit lit;		/* child is a leaf node */
		struct rnode *child;	/* child of unary op */
		struct {
			struct rnode *l_child; 
			struct rnode *r_child;
		} children;		/* children of binary op */
		} refs;
		short nullable;
		Pset firstposn, lastposn;
	} *Re_node;

typedef struct {			/* token node */
		short type;
		Re_node val;
	} *Tok_node;


typedef struct snode {
		Re_node val;
		int size;
		struct snode *next;
	} *Stack;

typedef struct dfa_st {
		Pset posns;
		int final;	    /* 1 if the state is a final state, 0 o/w */
		struct dfa_st *trans[128];
	} *Dfa_state;

typedef struct dfa_stset {
		Dfa_state st;
		struct dfa_stset *next_state;
	} *Dfa_state_set;