#ifndef	REGEX_H
#define REGEX_H

/*
 * Copyright (C) 1985 Richard M. Stallman
 * 
 * This software may be redistributed under the terms described in the file
 * LICENSE in this directory.
 */

#ifndef RE_NREGS
#define RE_NREGS 10
#endif

/* This data structure is used to represent a compiled pattern. */

struct re_pattern_buffer {
	char           *buffer;	/* Space holding the compiled pattern
				 * commands. */
	int             allocated;	/* Size of space that  buffer  points
					 * to */
	int             used;	/* Length of portion of buffer actually
				 * occupied */
	char           *fastmap;/* Pointer to fastmap, if any, or zero if
				 * none. */
	/*
	 * re_search uses the fastmap, if there is one, to skip quickly over
	 * totally implausible characters
	 */
	char           *translate;	/* Translate table to apply to all
					 * characters before comparing. Or
					 * zero for no translation. The
					 * translation is applied to a
					 * pattern when it is compiled and to
					 * data when it is matched. */
	char            fastmap_accurate;
	/*
	 * Set to zero when a new pattern is stored, set to one when the
	 * fastmap is updated from it.
	 */
	char            can_be_null;	/* Set to one by compiling fastmap if
					 * this pattern might match the null
					 * string. It does not necessarily
					 * match the null string in that
					 * case, but if this is zero, it
					 * cannot.  */
};

/*
 * Structure to store "register" contents data in.
 * 
 * Pass the address of such a structure as an argument to re_match, etc., if you
 * want this information back.
 * 
 * start[i] and end[i] record the string matched by \( ... \) grouping i, for i
 * from 1 to RE_NREGS - 1. start[0] and end[0] record the entire string
 * matched.
 */

struct re_registers {
	int             start[RE_NREGS];
	int             end[RE_NREGS];
};

#ifndef	NO_PROTO
char           *re_compile_pattern PROTO((char *, int, struct re_pattern_buffer *));
VOID re_compile_fastmap PROTO((struct re_pattern_buffer *));
int re_search 
PROTO((struct re_pattern_buffer *, char *, int, int, int,
       struct re_registers *));
int re_search_2 
PROTO((struct re_pattern_buffer *, char *, int, char *, int,
       int, int, struct re_registers *, int));
int re_match 
PROTO((struct re_pattern_buffer *, char *, int, int,
       struct re_registers *));
int re_match_2 
PROTO((struct re_pattern_buffer *, char *, int, char *, int,
       int, struct re_registers *, int));
char           *re_comp PROTO((char *));
int re_exec     PROTO((char *));
VOID           *alloca PROTO((unsigned));
#endif

/* Is this really advertised? */
extern VOID     re_compile_fastmap();
extern int      re_search(), re_search_2();
extern int      re_match(), re_match_2();

/* 4.2 bsd compatibility (yuck) */
extern char    *re_comp();
extern int      re_exec();

#ifdef SYNTAX_TABLE
extern char    *re_syntax_table;
#endif

#endif