V8/usr/src/cmd/awk/awk.h

#ifdef MYALLOC
	extern char *Malloc(), *Calloc();
#else
#	define	Malloc	malloc
#	define	Calloc	calloc
#	define	Free	free
#endif

#define	xfree(a)	{ if ((a) != NULL) { Free(a); a=NULL;} }

#ifdef	DEBUG
#	define	dprintf	if(dbg)printf
#else
#	define	dprintf(x1, x2, x3, x4)
#endif

#define	RECSIZE	(3 * 1024)	/* sets limit on records, fields, etc., etc. */

typedef double	Awkfloat;

extern char	**FS;
extern char	**RS;
extern char	**ORS;
extern char	**OFS;
extern char	**OFMT;
extern Awkfloat *NR;
extern Awkfloat *FNR;
extern Awkfloat *NF;
extern char	**FILENAME;

extern char	*record;
extern int	dbg;
extern int	lineno;
extern int	errorflag;
extern int	donefld;	/* 1 if record broken into fields */
extern int	donerec;	/* 1 if record is valid (no fld has changed */

/* Cell:  all information about a variable or constant */

typedef struct Cell {
	char	ctype;		/* OCELL, OBOOL, OJUMP, etc. */
	char	csub;		/* CCON, CTEMP, CFLD, etc. */
	char	*nval;		/* name, for variables only */
	char	*sval;		/* string value */
	Awkfloat fval;		/* value as number */
	unsigned tval;		/* type info: STR|NUM|ARR|FCN|FLD|CON|DONTFREE */
	struct Cell *cnext;	/* ptr to next if chained */
} Cell;

extern Cell	*symtab[];
extern Cell	*setsymtab(), *lookup(), **makesymtab();

extern Cell	*recloc;	/* location of input record */
extern Cell	*nrloc;		/* NR */
extern Cell	*fnrloc;	/* FNR */
extern Cell	*nfloc;		/* NF */

/* Cell.tval values: */
#define	NUM	01	/* number value is valid */
#define	STR	02	/* string value is valid */
#define DONTFREE 04	/* string space is not freeable */
#define	CON	010	/* this is a constant */
#define	ARR	020	/* this is an array */
#define	FCN	040	/* this is a function name */
#define FLD	0100	/* this is a field $1, $2, ... */
#define	REC	0200	/* this is $0 */

#define freeable(p)	(!((p)->tval & DONTFREE))

Awkfloat setfval(), getfval();
char	*setsval(), *getsval();
char	*tostring(), *tokname(), *malloc(), *calloc();
double	log(), sqrt(), exp(), atof();

/* function types */
#define	FLENGTH	1
#define	FSQRT	2
#define	FEXP	3
#define	FLOG	4
#define	FINT	5
#define	FSYSTEM	6
#define	FRAND	7
#define	FSRAND	8
#define	FSIN	9
#define	FCOS	10
#define	FATAN	11

/* Node:  parse tree is made of nodes, with Cell's at bottom */

typedef struct Node {
	int	ntype;
	struct	Node *nnext;
	int	lineno;
	int	nobj;
	struct Node *narg[1];	/* variable: actual size set by calling malloc */
} Node;

extern Node	*winner;
extern Node	*nullstat;


/* ctypes */
#define OCELL	1
#define OBOOL	2
#define OJUMP	3

/* Cell subtypes: csub */
#define CCOPY	6
#define CCON	5
#define CTEMP	4
#define CNAME	3 
#define CVAR	2
#define CFLD	1

/* bool subtypes */
#define BTRUE	11
#define BFALSE	12

/* jump subtypes */
#define JEXIT	21
#define JNEXT	22
#define	JBREAK	23
#define	JCONT	24
#define	JRET	25

/* node types */
#define NVALUE	1
#define NSTAT	2
#define NEXPR	3
#define	NFIELD	4

extern Cell	*(*proctab[])();
extern Cell	*nullproc();
extern Cell	*relop();
extern int	pairstack[], paircnt;

#define notlegal(n)	(n <= FIRSTTOKEN || n >= LASTTOKEN || proctab[n-FIRSTTOKEN] == nullproc)
#define isvalue(n)	((n)->ntype == NVALUE)
#define isexpr(n)	((n)->ntype == NEXPR)
#define isjump(n)	((n)->ctype == OJUMP)
#define isexit(n)	((n)->csub == JEXIT)
#define	isbreak(n)	((n)->csub == JBREAK)
#define	iscont(n)	((n)->csub == JCONT)
#define	isnext(n)	((n)->csub == JNEXT)
#define	isret(n)	((n)->csub == JRET)
#define isstr(n)	((n)->tval & STR)
#define isnum(n)	((n)->tval & NUM)
#define isarr(n)	((n)->tval & ARR)
#define isfunc(n)	((n)->tval & FCN)
#define istrue(n)	((n)->csub == BTRUE)
#define istemp(n)	((n)->csub == CTEMP)

#define MAXSYM	50
#define	HAT	0177	/* matches ^ in regular expr */
#define NCHARS	128
#define NSTATES	16
typedef struct fcell {
	int info;
	struct fcell *link;
} fcell;

typedef struct rrow {
	int ltype;
	int lval;
	fcell *lfollow;
} rrow;

typedef struct fa {
	char gototab[NSTATES][NCHARS];
	fcell *posns[NSTATES];
	char out[NSTATES];
	char initstat;
	char curstat;
	char accept;
	char reset;
	struct rrow re[1];
} fa;