# This is a shell archive.  Save it in a file, remove anything before
# this line, and then unpack it by entering "sh file".  Note, it may
# create directories; files and directories will be owned by you and
# have default permissions.
#
# This archive contains:
#
#	cpp5.c
#	cpp6.c
#
echo x - cpp5.c
sed 's/^X//' >cpp5.c << 'END-of-cpp5.c'
X/*
X *			    C P P 5 . C
X *		E x p r e s s i o n   E v a l u a t i o n
X *
X * Edit History
X * 31-Aug-84	MM	USENET net.sources release
X * 04-Oct-84	MM	__LINE__ and __FILE__ must call ungetstring()
X *			so they work correctly with token concatenation.
X *			Added string formal recognition.
X * 25-Oct-84	MM	"Short-circuit" evaluate #if's so that we
X *			don't print unnecessary error messages for
X *			#if !defined(FOO) && FOO != 0 && 10 / FOO ...
X * 31-Oct-84	ado/MM	Added token concatenation
X *  6-Nov-84	MM	Split from #define stuff, added sizeof stuff
X * 19-Nov-84	ado	#if error returns TRUE for (sigh) compatibility
X */
X
X#include	<stdio.h>
X#include	<ctype.h>
X#include	"cppdef.h"
X#include	"cpp.h"
X
X/*
X * Evaluate an #if expression.
X */
X
Xstatic char	*opname[] = {		/* For debug and error messages	*/
X"end of expression", "val", "id",
X  "+",   "-",  "*",  "/",  "%",
X  "<<", ">>",  "&",  "|",  "^",
X  "==", "!=",  "<", "<=", ">=",  ">",
X  "&&", "||",  "?",  ":",  ",",
X  "unary +", "unary -", "~", "!",  "(",  ")", "(none)",
X};
X
X/*
X * opdope[] has the operator precedence:
X *     Bits
X *	  7	Unused (so the value is always positive)
X *	6-2	Precedence (000x .. 017x)
X *	1-0	Binary op. flags:
X *	    01	The binop flag should be set/cleared when this op is seen.
X *	    10	The new value of the binop flag.
X * Note:  Expected, New binop
X * constant	0	1	Binop, end, or ) should follow constants
X * End of line	1	0	End may not be preceeded by an operator
X * binary	1	0	Binary op follows a value, value follows.
X * unary	0	0	Unary op doesn't follow a value, value follows
X *   (		0	0	Doesn't follow value, value or unop follows
X *   )		1	1	Follows value.  Op follows.
X */
X
Xstatic char	opdope[OP_MAX] = {
X  0001,					/* End of expression		*/
X  0002,					/* Digit			*/
X  0000,					/* Letter (identifier)		*/
X  0141, 0141, 0151, 0151, 0151,		/* ADD, SUB, MUL, DIV, MOD	*/
X  0131, 0131, 0101, 0071, 0071,		/* ASL, ASR, AND,  OR, XOR	*/
X  0111, 0111, 0121, 0121, 0121,	0121,	/*  EQ,  NE,  LT,  LE,  GE,  GT	*/
X  0061, 0051, 0041, 0041, 0031,		/* ANA, ORO, QUE, COL, CMA	*/
X/*
X * Unary op's follow
X */
X  0160, 0160, 0160, 0160,		/* NEG, PLU, COM, NOT		*/
X  0170, 0013, 0023,			/* LPA, RPA, END		*/
X};
X/*
X * OP_QUE and OP_RPA have alternate precedences:
X */
X#define	OP_RPA_PREC	0013
X#define OP_QUE_PREC	0034
X
X/*
X * S_ANDOR and S_QUEST signal "short-circuit" boolean evaluation, so that
X *	#if FOO != 0 && 10 / FOO ...
X * doesn't generate an error message.  They are stored in optab.skip.
X */
X#define S_ANDOR		2
X#define S_QUEST		1
X
Xtypedef struct optab {
X    char	op;			/* Operator			*/
X    char	prec;			/* Its precedence		*/
X    char	skip;			/* Short-circuit: TRUE to skip	*/
X} OPTAB;
Xstatic int	evalue;			/* Current value from evallex()	*/
X
X#ifdef	nomacargs
XFILE_LOCAL int
Xisbinary(op)
Xregister int	op;
X{
X	return (op >= FIRST_BINOP && op <= LAST_BINOP);
X}
X
XFILE_LOCAL int
Xisunary(op)
Xregister int	op;
X{
X	return (op >= FIRST_UNOP && op <= LAST_UNOP);
X}
X#else
X#define	isbinary(op)	(op >= FIRST_BINOP && op <= LAST_BINOP)
X#define	isunary(op)	(op >= FIRST_UNOP  && op <= LAST_UNOP)
X#endif
X
X/*
X * The following definitions are used to specify basic variable sizes.
X */
X
X#ifndef	S_CHAR
X#define	S_CHAR		(sizeof (char))
X#endif
X#ifndef	S_SINT
X#define	S_SINT		(sizeof (short int))
X#endif
X#ifndef	S_INT
X#define	S_INT		(sizeof (int))
X#endif
X#ifndef	S_LINT
X#define	S_LINT		(sizeof (long int))
X#endif
X#ifndef	S_FLOAT
X#define	S_FLOAT		(sizeof (float))
X#endif
X#ifndef	S_DOUBLE
X#define	S_DOUBLE	(sizeof (double))
X#endif
X#ifndef	S_PCHAR
X#define	S_PCHAR		(sizeof (char *))
X#endif
X#ifndef	S_PSINT
X#define	S_PSINT		(sizeof (short int *))
X#endif
X#ifndef	S_PINT
X#define	S_PINT		(sizeof (int *))
X#endif
X#ifndef	S_PLINT
X#define	S_PLINT		(sizeof (long int *))
X#endif
X#ifndef	S_PFLOAT
X#define	S_PFLOAT	(sizeof (float *))
X#endif
X#ifndef	S_PDOUBLE
X#define	S_PDOUBLE	(sizeof (double *))
X#endif
X#ifndef	S_PFPTR
X#define S_PFPTR		(sizeof (int (*)()))
X#endif
X
Xtypedef struct types {
X    short	type;			/* This is the bit if		*/
X    char	*name;			/* this is the token word	*/
X} TYPES;
X
Xstatic TYPES basic_types[] = {
X	{ T_CHAR,	"char",		},
X	{ T_INT,	"int",		},
X	{ T_FLOAT,	"float",	},
X	{ T_DOUBLE,	"double",	},
X	{ T_SHORT,	"short",	},
X	{ T_LONG,	"long",		},
X	{ T_SIGNED,	"signed",	},
X	{ T_UNSIGNED,	"unsigned",	},
X	{ 0,		NULL,		},	/* Signal end		*/
X};
X
X/*
X * Test_table[] is used to test for illegal combinations.
X */
Xstatic short test_table[] = {
X	T_FLOAT | T_DOUBLE | T_LONG | T_SHORT,
X	T_FLOAT | T_DOUBLE | T_CHAR | T_INT,
X	T_FLOAT | T_DOUBLE | T_SIGNED | T_UNSIGNED,
X	T_LONG  | T_SHORT  | T_CHAR,
X	0						/* end marker	*/
X};
X
X/*
X * The order of this table is important -- it is also referenced by
X * the command line processor to allow run-time overriding of the
X * built-in size values.  The order must not be changed:
X *	char, short, int, long, float, double (func pointer)
X */
XSIZES size_table[] = {
X    { T_CHAR,	S_CHAR,		S_PCHAR		},	/* char		*/
X    { T_SHORT,	S_SINT,		S_PSINT		},	/* short int	*/
X    { T_INT,	S_INT,		S_PINT		},	/* int		*/
X    { T_LONG,	S_LINT,		S_PLINT		},	/* long		*/
X    { T_FLOAT,	S_FLOAT,	S_PFLOAT	},	/* float	*/
X    { T_DOUBLE,	S_DOUBLE,	S_PDOUBLE	},	/* double	*/
X    { T_FPTR,	0,		S_PFPTR		},	/* int (*()) 	*/
X    { 0,	0,		0		},	/* End of table	*/
X};
X
Xint
Xeval()
X/*
X * Evaluate an expression.  Straight-forward operator precedence.
X * This is called from control() on encountering an #if statement.
X * It calls the following routines:
X * evallex	Lexical analyser -- returns the type and value of
X *		the next input token.
X * evaleval	Evaluate the current operator, given the values on
X *		the value stack.  Returns a pointer to the (new)
X *		value stack.
X * For compatiblity with older cpp's, this return returns 1 (TRUE)
X * if a syntax error is detected.
X */
X{
X	register int	op;		/* Current operator		*/
X	register int	*valp;		/* -> value vector		*/
X	register OPTAB	*opp;		/* Operator stack		*/
X	int		prec;		/* Op precedence		*/
X	int		binop;		/* Set if binary op. needed	*/
X	int		op1;		/* Operand from stack		*/
X	int		skip;		/* For short-circuit testing	*/
X	int		value[NEXP];	/* Value stack			*/
X	OPTAB		opstack[NEXP];	/* Operand stack		*/
X	extern int	*evaleval();	/* Does actual evaluation	*/
X
X	valp = value;
X	opp = opstack;
X	opp->op = OP_END;		/* Mark bottom of stack		*/
X	opp->prec = opdope[OP_END];	/* And its precedence		*/
X	opp->skip = 0;			/* Not skipping now		*/
X	binop = 0;
Xagain:	;
X#ifdef	DEBUG_EVAL
X	printf("In #if at again: skip = %d, binop = %d, line is: %s",
X	    opp->skip, binop, infile->bptr);
X#endif
X	if ((op = evallex(opp->skip)) == OP_SUB && binop == 0)
X	    op = OP_NEG;			/* Unary minus		*/
X	else if (op == OP_ADD && binop == 0)
X	    op = OP_PLU;			/* Unary plus		*/
X	else if (op == OP_FAIL)
X	    return (1);				/* Error in evallex	*/
X#ifdef	DEBUG_EVAL
X	printf("op = %s, opdope = %03o, binop = %d, skip = %d\n",
X	    opname[op], opdope[op], binop, opp->skip);
X#endif
X	if (op == DIG) {			/* Value?		*/
X	    if (binop != 0) {
X		cerror("misplaced constant in #if", NULLST);
X		return (1);
X	    }
X	    else if (valp >= &value[NEXP-1]) {
X		cerror("#if value stack overflow", NULLST);
X		return (1);
X	    }
X	    else {
X#ifdef	DEBUG_EVAL
X		printf("pushing %d onto value stack[%d]\n",
X		    evalue, valp - value);
X#endif
X		*valp++ = evalue;
X		binop = 1;
X	    }
X	    goto again;
X	}
X	else if (op > OP_END) {
X	    cerror("Illegal #if line", NULLST);
X	    return (1);
X	}
X	prec = opdope[op];
X	if (binop != (prec & 1)) {
X	    cerror("Operator %s in incorrect context", opname[op]);
X	    return (1);
X	}
X	binop = (prec & 2) >> 1;
X	for (;;) {
X#ifdef	DEBUG_EVAL
X	    printf("op %s, prec %d., stacked op %s, prec %d, skip %d\n",
X		opname[op], prec, opname[opp->op], opp->prec, opp->skip);
X#endif
X	    if (prec > opp->prec) {
X		if (op == OP_LPA)
X		    prec = OP_RPA_PREC;
X		else if (op == OP_QUE)
X		    prec = OP_QUE_PREC;
X		op1 = opp->skip;		/* Save skip for test	*/
X		/*
X		 * Push operator onto op. stack.
X		 */
X		opp++;
X		if (opp >= &opstack[NEXP]) {
X		    cerror("expression stack overflow at op \"%s\"",
X			opname[op]);
X		    return (1);
X		}
X		opp->op = op;
X		opp->prec = prec;
X		skip = (valp[-1] != 0);		/* Short-circuit tester	*/
X		/*
X		 * Do the short-circuit stuff here.  Short-circuiting
X		 * stops automagically when operators are evaluated.
X		 */
X		if ((op == OP_ANA && !skip)
X		 || (op == OP_ORO && skip))
X		    opp->skip = S_ANDOR;	/* And/or skip starts	*/
X		else if (op == OP_QUE)		/* Start of ?: operator	*/
X		    opp->skip = (op1 & S_ANDOR) | ((!skip) ? S_QUEST : 0);
X		else if (op == OP_COL) {	/* : inverts S_QUEST	*/
X		    opp->skip = (op1 & S_ANDOR)
X			      | (((op1 & S_QUEST) != 0) ? 0 : S_QUEST);
X		}
X		else {				/* Other ops leave	*/
X		    opp->skip = op1;		/*  skipping unchanged.	*/
X		}
X#ifdef	DEBUG_EVAL
X		printf("stacking %s, valp[-1] == %d at %s",
X		    opname[op], valp[-1], infile->bptr);
X		dumpstack(opstack, opp, value, valp);
X#endif
X		goto again;
X	    }
X	    /*
X	     * Pop operator from op. stack and evaluate it.
X	     * End of stack and '(' are specials.
X	     */
X	    skip = opp->skip;			/* Remember skip value	*/
X	    switch ((op1 = opp->op)) {		/* Look at stacked op	*/
X	    case OP_END:			/* Stack end marker	*/
X		if (op == OP_EOE)
X		    return (valp[-1]);		/* Finished ok.		*/
X		goto again;			/* Read another op.	*/
X
X	    case OP_LPA:			/* ( on stack		*/
X		if (op != OP_RPA) {		/* Matches ) on input	*/
X		    cerror("unbalanced paren's, op is \"%s\"", opname[op]);
X		    return (1);
X		}
X		opp--;				/* Unstack it		*/
X		/* goto again;			-- Fall through		*/
X
X	    case OP_QUE:
X		goto again;			/* Evaluate true expr.	*/
X
X	    case OP_COL:			/* : on stack.		*/
X		opp--;				/* Unstack :		*/
X		if (opp->op != OP_QUE) {	/* Matches ? on stack?	*/
X		    cerror("Misplaced '?' or ':', previous operator is %s",
X			opname[opp->op]);
X		    return (1);
X		}
X		/*
X		 * Evaluate op1.
X		 */
X	    default:				/* Others:		*/
X		opp--;				/* Unstack the operator	*/
X#ifdef	DEBUG_EVAL
X		printf("Stack before evaluation of %s\n", opname[op1]);
X		dumpstack(opstack, opp, value, valp);
X#endif
X		valp = evaleval(valp, op1, skip);
X#ifdef	DEBUG_EVAL
X		printf("Stack after evaluation\n");
X		dumpstack(opstack, opp, value, valp);
X#endif
X	    }					/* op1 switch end	*/
X	}					/* Stack unwind loop	*/
X}
X
XFILE_LOCAL int
Xevallex(skip)
Xint		skip;		/* TRUE if short-circuit evaluation	*/
X/*
X * Return next eval operator or value.  Called from eval().  It
X * calls a special-purpose routines for 'char' strings and
X * numeric values:
X * evalchar	called to evaluate 'x'
X * evalnum	called to evaluate numbers.
X */
X{
X	register int	c, c1, t;
X
Xagain:  do {					/* Collect the token	*/
X	    c = skipws();
X	    if ((c = macroid(c)) == EOF_CHAR || c == '\n') {
X		unget();
X		return (OP_EOE);		/* End of expression	*/
X	    }
X	} while ((t = type[c]) == LET && catenate());
X	if (t == INV) {				/* Total nonsense	*/
X	    if (!skip) {
X		if (isascii(c) && isprint(c))
X		    cierror("illegal character '%c' in #if", c);
X		else
X		    cierror("illegal character (%d decimal) in #if", c);
X	    }
X	    return (OP_FAIL);
X	}
X	else if (t == QUO) {			/* ' or "		*/
X	    if (c == '\'') {			/* Character constant	*/
X		evalue = evalchar(skip);	/* Somewhat messy	*/
X#ifdef	DEBUG_EVAL
X		printf("evalchar returns %d.\n", evalue);
X#endif
X		return (DIG);			/* Return a value	*/
X	    }
X	    cerror("Can't use a string in an #if", NULLST);
X	    return (OP_FAIL);
X	}
X	else if (t == LET) {			/* ID must be a macro	*/
X	    if (streq(token, "defined")) {	/* Or defined name	*/
X		c1 = c = skipws();
X		if (c == '(')			/* Allow defined(name)	*/
X		    c = skipws();
X		if (type[c] == LET) {
X		    evalue = (lookid(c) != NULL);
X		    if (c1 != '('		/* Need to balance	*/
X		     || skipws() == ')')	/* Did we balance?	*/
X			return (DIG);		/* Parsed ok		*/
X		}
X		cerror("Bad #if ... defined() syntax", NULLST);
X		return (OP_FAIL);
X	    }
X	    else if (streq(token, "sizeof"))	/* New sizeof hackery	*/
X		return (dosizeof());		/* Gets own routine	*/
X	    /*
X	     * The Draft ANSI C Standard says that an undefined symbol
X	     * in an #if has the value zero.  We are a bit pickier,
X	     * warning except where the programmer was careful to write
X	     * 		#if defined(foo) ? foo : 0
X	     */
X#ifdef VERBOSE
X	     if (!skip)
X  		cwarn("undefined symbol \"%s\" in #if, 0 used", token);
X#endif
X	    evalue = 0;
X	    return (DIG);
X	}
X	else if (t == DIG) {			/* Numbers are harder	*/
X	    evalue = evalnum(c);
X#ifdef	DEBUG_EVAL
X	    printf("evalnum returns %d.\n", evalue);
X#endif
X	}
X	else if (strchr("!=<>&|\\", c) != NULL) {
X	    /*
X	     * Process a possible multi-byte lexeme.
X	     */
X	    c1 = cget();			/* Peek at next char	*/
X	    switch (c) {
X	    case '!':
X		if (c1 == '=')
X		    return (OP_NE);
X		break;
X
X	    case '=':
X		if (c1 != '=') {		/* Can't say a=b in #if	*/
X		    unget();
X		    cerror("= not allowed in #if", NULLST);
X		    return (OP_FAIL);
X		}
X		return (OP_EQ);
X
X	    case '>':
X	    case '<':
X		if (c1 == c)
X		    return ((c == '<') ? OP_ASL : OP_ASR);
X		else if (c1 == '=')
X		    return ((c == '<') ? OP_LE  : OP_GE);
X		break;
X
X	    case '|':
X	    case '&':
X		if (c1 == c)
X		    return ((c == '|') ? OP_ORO : OP_ANA);
X		break;
X
X	    case '\\':
X		if (c1 == '\n')			/* Multi-line if	*/
X		    goto again;
X		cerror("Unexpected \\ in #if", NULLST);
X		return (OP_FAIL);
X	    }
X	    unget();
X	}
X	return (t);
X}
X
XFILE_LOCAL int
Xdosizeof()
X/*
X * Process the sizeof (basic type) operation in an #if string.
X * Sets evalue to the size and returns
X *	DIG		success
X *	OP_FAIL		bad parse or something.
X */
X{
X	register int	c;
X	register TYPES	*tp;
X	register SIZES	*sizp;
X	register short	*testp;
X	short		typecode;
X
X	if ((c = skipws()) != '(')
X	    goto nogood;
X	/*
X	 * Scan off the tokens.
X	 */
X	typecode = 0;
X	while ((c = skipws())) {
X	    if ((c = macroid(c)) == EOF_CHAR || c == '\n')
X		goto nogood;			/* End of line is a bug	*/
X	    else if (c == '(') {		/* thing (*)() func ptr	*/
X		if (skipws() == '*'
X		 && skipws() == ')') {		/* We found (*)		*/
X		    if (skipws() != '(')	/* Let () be optional	*/
X			unget();
X		    else if (skipws() != ')')
X			goto nogood;
X		    typecode |= T_FPTR;		/* Function pointer	*/
X		}
X		else {				/* Junk is a bug	*/
X		    goto nogood;
X		}
X	    }
X	    else if (type[c] != LET)		/* Exit if not a type	*/
X		break;
X	    else if (!catenate()) {		/* Maybe combine tokens	*/
X		/*
X		 * Look for this unexpandable token in basic_types.
X		 * The code accepts "int long" as well as "long int"
X		 * which is a minor bug as bugs go (and one shared with
X		 * a lot of C compilers).
X		 */
X		for (tp = basic_types; tp->name != NULLST; tp++) {
X		    if (streq(token, tp->name))
X			break;
X		}
X		if (tp->name == NULLST) {
X		    cerror("#if sizeof, unknown type \"%s\"", token);
X		    return (OP_FAIL);
X		}
X		typecode |= tp->type;		/* Or in the type bit	*/
X	    }
X	}
X	/*
X	 * We are at the end of the type scan.  Chew off '*' if necessary.
X	 */
X	if (c == '*') {
X	    typecode |= T_PTR;
X	    c = skipws();
X	}
X	if (c == ')') {				/* Last syntax check	*/
X	    for (testp = test_table; *testp != 0; testp++) {
X		if (!bittest(typecode & *testp)) {
X		    cerror("#if ... sizeof: illegal type combination", NULLST);
X		    return (OP_FAIL);
X		}
X	    }
X	    /*
X	     * We assume that all function pointers are the same size:
X	     *		sizeof (int (*)()) == sizeof (float (*)())
X	     * We assume that signed and unsigned don't change the size:
X	     *		sizeof (signed int) == (sizeof unsigned int)
X	     */
X	    if ((typecode & T_FPTR) != 0)	/* Function pointer	*/
X		typecode = T_FPTR | T_PTR;
X	    else {				/* Var or var * datum	*/
X		typecode &= ~(T_SIGNED | T_UNSIGNED);
X		if ((typecode & (T_SHORT | T_LONG)) != 0)
X		    typecode &= ~T_INT;
X	    }
X	    if ((typecode & ~T_PTR) == 0) {
X		cerror("#if sizeof() error, no type specified", NULLST);
X		return (OP_FAIL);
X	    }
X	    /*
X	     * Exactly one bit (and possibly T_PTR) may be set.
X	     */
X	    for (sizp = size_table; sizp->bits != 0; sizp++) {
X		if ((typecode & ~T_PTR) == sizp->bits) {
X		    evalue = ((typecode & T_PTR) != 0)
X			? sizp->psize : sizp->size;
X		    return (DIG);
X		}
X	    }					/* We shouldn't fail	*/
X	    cierror("#if ... sizeof: bug, unknown type code 0x%x", typecode);
X	    return (OP_FAIL);
X	}
X
Xnogood:	unget();
X	cerror("#if ... sizeof() syntax error", NULLST);
X	return (OP_FAIL);
X}
X
XFILE_LOCAL int
Xbittest(value)
X/*
X * TRUE if value is zero or exactly one bit is set in value.
X */
X{
X#if (4096 & ~(-4096)) == 0
X	return ((value & ~(-value)) == 0);
X#else
X	/*
X	 * Do it the hard way (for non 2's complement machines)
X	 */
X	return (value == 0 || value ^ (value - 1) == (value * 2 - 1));
X#endif
X}
X
XFILE_LOCAL int
Xevalnum(c)
Xregister int	c;
X/*
X * Expand number for #if lexical analysis.  Note: evalnum recognizes
X * the unsigned suffix, but only returns a signed int value.
X */
X{
X	register int	value;
X	register int	base;
X	register int	c1;
X
X	if (c != '0')
X	    base = 10;
X	else if ((c = cget()) == 'x' || c == 'X') {
X		base = 16;
X		c = cget();
X	}
X	else base = 8;
X	value = 0;
X	for (;;) {
X	    c1 = c;
X	    if (isascii(c) && isupper(c1))
X		c1 = tolower(c1);
X	    if (c1 >= 'a')
X		c1 -= ('a' - 10);
X	    else c1 -= '0';
X	    if (c1 < 0 || c1 >= base)
X		break;
X	    value *= base;
X	    value += c1;
X	    c = cget();
X	}
X	if (c == 'u' || c == 'U')	/* Unsigned nonsense		*/
X	    c = cget();
X	unget();
X	return (value);
X}
X
XFILE_LOCAL int
Xevalchar(skip)
Xint		skip;		/* TRUE if short-circuit evaluation	*/
X/*
X * Get a character constant
X */
X{
X	register int	c;
X	register int	value;
X	register int	count;
X
X	instring = TRUE;
X	if ((c = cget()) == '\\') {
X	    switch ((c = cget())) {
X	    case 'a':				/* New in Standard	*/
X#if ('a' == '\a' || '\a' == ALERT)
X		value = ALERT;			/* Use predefined value	*/
X#else
X		value = '\a';			/* Use compiler's value	*/
X#endif
X		break;
X
X	    case 'b':
X		value = '\b';
X		break;
X
X	    case 'f':
X		value = '\f';
X		break;
X
X	    case 'n':
X		value = '\n';
X		break;
X
X	    case 'r':
X		value = '\r';
X		break;
X
X	    case 't':
X		value = '\t';
X		break;
X
X	    case 'v':				/* New in Standard	*/
X#if ('v' == '\v' || '\v' == VT)
X		value = VT;			/* Use predefined value	*/
X#else
X		value = '\v';			/* Use compiler's value	*/
X#endif
X		break;
X
X	    case 'x':				/* '\xFF'		*/
X		count = 3;
X		value = 0;
X		while ((((c = get()) >= '0' && c <= '9')
X		     || (c >= 'a' && c <= 'f')
X		     || (c >= 'A' && c <= 'F'))
X		    && (--count >= 0)) {
X			value *= 16;
X			value += (c <= '9') ? (c - '0') : ((c & 0xF) + 9);
X		}
X		unget();
X		break;
X
X	    default:
X		if (c >= '0' && c <= '7') {
X		    count = 3;
X		    value = 0;
X		    while (c >= '0' && c <= '7' && --count >= 0) {
X			value *= 8;
X			value += (c - '0');
X			c = get();
X		    }
X		    unget();
X		}
X		else value = c;
X		break;
X	    }
X	}
X	else if (c == '\'')
X	    value = 0;
X	else value = c;
X	/*
X	 * We warn on multi-byte constants and try to hack
X	 * (big|little)endian machines.
X	 */
X#if BIG_ENDIAN
X	count = 0;
X#endif
X	while ((c = get()) != '\'' && c != EOF_CHAR && c != '\n') {
X	    if (!skip)
X		ciwarn("multi-byte constant '%c' isn't portable", c);
X#if BIG_ENDIAN
X	    count += BITS_CHAR;
X	    value += (c << count);
X#else
X	    value <<= BITS_CHAR;
X	    value += c;
X#endif
X	}
X	instring = FALSE;
X	return (value);
X}
X
XFILE_LOCAL int *
Xevaleval(valp, op, skip)
Xregister int	*valp;
Xint		op;
Xint		skip;		/* TRUE if short-circuit evaluation	*/
X/*
X * Apply the argument operator to the data on the value stack.
X * One or two values are popped from the value stack and the result
X * is pushed onto the value stack.
X *
X * OP_COL is a special case.
X *
X * evaleval() returns the new pointer to the top of the value stack.
X */
X{
X	register int	v1, v2;
X
X	if (isbinary(op))
X	    v2 = *--valp;
X	v1 = *--valp;
X#ifdef	DEBUG_EVAL
X	printf("%s op %s", (isbinary(op)) ? "binary" : "unary",
X	    opname[op]);
X	if (isbinary(op))
X	    printf(", v2 = %d.", v2);
X	printf(", v1 = %d.\n", v1);
X#endif
X	switch (op) {
X	case OP_EOE:
X	     break;
X
X	case OP_ADD:
X	    v1 += v2;
X	    break;
X
X	case OP_SUB:
X	    v1 -= v2;
X	    break;
X
X	case OP_MUL:
X	    v1 *= v2;
X	    break;
X
X	case OP_DIV:
X	case OP_MOD:
X	    if (v2 == 0) {
X		if (!skip) {
X		    cwarn("%s by zero in #if, zero result assumed",
X			(op == OP_DIV) ? "divide" : "mod");
X		}
X		v1 = 0;
X	    }
X	    else if (op == OP_DIV)
X		v1 /= v2;
X	    else
X		v1 %= v2;
X	    break;
X
X	case OP_ASL:
X	    v1 <<= v2;
X	    break;
X
X	case OP_ASR:
X	    v1 >>= v2;
X	    break;
X
X	case OP_AND:
X	    v1 &= v2;
X	    break;
X
X	case OP_OR:
X	    v1 |= v2;
X	    break;
X
X	case OP_XOR:
X	    v1 ^= v2;
X	    break;
X
X	case OP_EQ:
X	    v1 = (v1 == v2);
X	    break;
X
X	case OP_NE:
X	    v1 = (v1 != v2);
X	    break;
X
X	case OP_LT:
X	    v1 = (v1 < v2);
X	    break;
X
X	case OP_LE:
X	    v1 = (v1 <= v2);
X	    break;
X
X	case OP_GE:
X	    v1 = (v1 >= v2);
X	    break;
X
X	case OP_GT:
X	    v1 = (v1 > v2);
X	    break;
X
X	case OP_ANA:
X	    v1 = (v1 && v2);
X	    break;
X
X	case OP_ORO:
X	    v1 = (v1 || v2);
X	    break;
X
X	case OP_COL:
X	    /*
X	     * v1 has the "true" value, v2 the "false" value.
X	     * The top of the value stack has the test.
X	     */
X	    v1 = (*--valp) ? v1 : v2;
X	    break;
X
X	case OP_NEG:
X	    v1 = (-v1);
X	    break;
X
X	case OP_PLU:
X	    break;
X
X	case OP_COM:
X	    v1 = ~v1;
X	    break;
X
X	case OP_NOT:
X	    v1 = !v1;
X	    break;
X
X	default:
X	    cierror("#if bug, operand = %d.", op);
X	    v1 = 0;
X	}
X	*valp++ = v1;
X	return (valp);
X}
X
X#ifdef	DEBUG_EVAL
Xdumpstack(opstack, opp, value, valp)
XOPTAB		opstack[NEXP];	/* Operand stack		*/
Xregister OPTAB	*opp;		/* Operator stack		*/
Xint		value[NEXP];	/* Value stack			*/
Xregister int	*valp;		/* -> value vector		*/
X{
X	printf("index op prec skip name -- op stack at %s", infile->bptr);
X	while (opp > opstack) {
X	    printf(" [%2d] %2d  %03o    %d %s\n", opp - opstack,
X		opp->op, opp->prec, opp->skip, opname[opp->op]);
X	    opp--;
X	}
X	while (--valp >= value) {
X	    printf("value[%d] = %d\n", (valp - value), *valp);
X	}
X}
X#endif
X
END-of-cpp5.c
echo x - cpp6.c
sed 's/^X//' >cpp6.c << 'END-of-cpp6.c'
X/*
X *			    C P P 6 . C
X *		S u p p o r t   R o u t i n e s
X *
X * Edit History
X * 25-May-84 MM		Added 8-bit support to type table.
X * 30-May-84 ARF	sharp() should output filename in quotes
X * 02-Aug-84 MM		Newline and #line hacking.  sharp() now in cpp1.c
X * 31-Aug-84 MM		USENET net.sources release
X * 11-Sep-84 ado/MM	Keepcomments, also line number pathological
X * 12-Sep-84 ado/MM	bug if comment changes to space and we unget later.
X * 03-Oct-84 gkr/MM	Fixed scannumber bug for '.e' (as in struct.element).
X * 04-Oct-84 MM		Added ungetstring() for token concatenation
X * 08-Oct-84 MM		Yet another attack on number scanning
X * 31-Oct-84 ado	Parameterized $ in identifiers
X *  2-Nov-84 MM		Token concatenation is messier than I thought
X *  6-Dec-84 MM		\<nl> is everywhere invisible.
X */
X
X#include	<stdio.h>
X#include	<ctype.h>
X#include	"cppdef.h"
X#include	"cpp.h"
X
X/*
X * skipnl()	skips over input text to the end of the line.
X * skipws()	skips over "whitespace" (spaces or tabs), but
X *		not skip over the end of the line.  It skips over
X *		TOK_SEP, however (though that shouldn't happen).
X * scanid()	reads the next token (C identifier) into token[].
X *		The caller has already read the first character of
X *		the identifier.  Unlike macroid(), the token is
X *		never expanded.
X * macroid()	reads the next token (C identifier) into token[].
X *		If it is a #defined macro, it is expanded, and
X *		macroid() returns TRUE, otherwise, FALSE.
X * catenate()	Does the dirty work of token concatenation, TRUE if it did.
X * scanstring()	Reads a string from the input stream, calling
X *		a user-supplied function for each character.
X *		This function may be output() to write the
X *		string to the output file, or save() to save
X *		the string in the work buffer.
X * scannumber()	Reads a C numeric constant from the input stream,
X *		calling the user-supplied function for each
X *		character.  (output() or save() as noted above.)
X * save()	Save one character in the work[] buffer.
X * savestring()	Saves a string in malloc() memory.
X * getfile()	Initialize a new FILEINFO structure, called when
X *		#include opens a new file, or a macro is to be
X *		expanded.
X * getmem()	Get a specified number of bytes from malloc memory.
X * output()	Write one character to stdout (calling putchar) --
X *		implemented as a function so its address may be
X *		passed to scanstring() and scannumber().
X * lookid()	Scans the next token (identifier) from the input
X *		stream.  Looks for it in the #defined symbol table.
X *		Returns a pointer to the definition, if found, or NULL
X *		if not present.  The identifier is stored in token[].
X * defnedel()	Define enter/delete subroutine.  Updates the
X *		symbol table.
X * get()	Read the next byte from the current input stream,
X *		handling end of (macro/file) input and embedded
X *		comments appropriately.  Note that the global
X *		instring is -- essentially -- a parameter to get().
X * cget()	Like get(), but skip over TOK_SEP.
X * unget()	Push last gotten character back on the input stream.
X * cerror(), cwarn(), cfatal(), cierror(), ciwarn()
X *		These routines format an print messages to the user.
X *		cerror & cwarn take a format and a single string argument.
X *		cierror & ciwarn take a format and a single int (char) argument.
X *		cfatal takes a format and a single string argument.
X */
X
X/*
X * This table must be rewritten for a non-Ascii machine.
X *
X * Note that several "non-visible" characters have special meaning:
X * Hex 1D DEF_MAGIC -- a flag to prevent #define recursion.
X * Hex 1E TOK_SEP   -- a delimiter for token concatenation
X * Hex 1F COM_SEP   -- a zero-width whitespace for comment concatenation
X */
X#if TOK_SEP != 0x1E || COM_SEP != 0x1F || DEF_MAGIC != 0x1D
X	<< error type table isn't correct >>
X#endif
X
X#if OK_DOLLAR
X#define	DOL	LET
X#else
X#define	DOL	000
X#endif
X
Xchar type[256] = {		/* Character type codes    Hex		*/
X   END,   000,   000,   000,   000,   000,   000,   000, /* 00		*/
X   000,   SPA,   000,   000,   000,   000,   000,   000, /* 08		*/
X   000,   000,   000,   000,   000,   000,   000,   000, /* 10		*/
X   000,   000,   000,   000,   000,   LET,   000,   SPA, /* 18		*/
X   SPA,OP_NOT,   QUO,   000,   DOL,OP_MOD,OP_AND,   QUO, /* 20  !"#$%&'	*/
XOP_LPA,OP_RPA,OP_MUL,OP_ADD,   000,OP_SUB,   DOT,OP_DIV, /* 28 ()*+,-./	*/
X   DIG,   DIG,   DIG,   DIG,   DIG,   DIG,   DIG,   DIG, /* 30 01234567	*/
X   DIG,   DIG,OP_COL,   000, OP_LT, OP_EQ, OP_GT,OP_QUE, /* 38 89:;<=>?	*/
X   000,   LET,   LET,   LET,   LET,   LET,   LET,   LET, /* 40 @ABCDEFG	*/
X   LET,   LET,   LET,   LET,   LET,   LET,   LET,   LET, /* 48 HIJKLMNO	*/
X   LET,   LET,   LET,   LET,   LET,   LET,   LET,   LET, /* 50 PQRSTUVW	*/
X   LET,   LET,   LET,   000,   BSH,   000,OP_XOR,   LET, /* 58 XYZ[\]^_	*/
X   000,   LET,   LET,   LET,   LET,   LET,   LET,   LET, /* 60 `abcdefg	*/
X   LET,   LET,   LET,   LET,   LET,   LET,   LET,   LET, /* 68 hijklmno	*/
X   LET,   LET,   LET,   LET,   LET,   LET,   LET,   LET, /* 70 pqrstuvw	*/
X   LET,   LET,   LET,   000, OP_OR,   000,OP_NOT,   000, /* 78 xyz{|}~	*/
X   000,   000,   000,   000,   000,   000,   000,   000, /*   80 .. FF	*/
X   000,   000,   000,   000,   000,   000,   000,   000, /*   80 .. FF	*/
X   000,   000,   000,   000,   000,   000,   000,   000, /*   80 .. FF	*/
X   000,   000,   000,   000,   000,   000,   000,   000, /*   80 .. FF	*/
X   000,   000,   000,   000,   000,   000,   000,   000, /*   80 .. FF	*/
X   000,   000,   000,   000,   000,   000,   000,   000, /*   80 .. FF	*/
X   000,   000,   000,   000,   000,   000,   000,   000, /*   80 .. FF	*/
X   000,   000,   000,   000,   000,   000,   000,   000, /*   80 .. FF	*/
X};
X
Xskipnl()
X/*
X * Skip to the end of the current input line.
X */
X{
X	register int		c;
X
X	do {				/* Skip to newline	*/
X	    c = get();
X	} while (c != '\n' && c != EOF_CHAR);
X}
X
Xint
Xskipws()
X/*
X * Skip over whitespace
X */
X{
X	register int		c;
X
X	do {				/* Skip whitespace	*/
X	    c = get();
X#if COMMENT_INVISIBLE
X	} while (type[c] == SPA || c == COM_SEP);
X#else
X	} while (type[c] == SPA);
X#endif
X	return (c);
X}
X
Xscanid(c)
Xregister int	c;				/* First char of id	*/
X/*
X * Get the next token (an id) into the token buffer.
X * Note: this code is duplicated in lookid().
X * Change one, change both.
X */
X{
X	register char	*bp;
X
X	if (c == DEF_MAGIC)			/* Eat the magic token	*/
X	    c = get();				/* undefiner.		*/
X	bp = token;
X	do {
X	    if (bp < &token[IDMAX])		/* token dim is IDMAX+1	*/
X		*bp++ = c;
X	    c = get();
X	} while (type[c] == LET || type[c] == DIG);
X	unget();
X	*bp = EOS;
X}
X
Xint
Xmacroid(c)
Xregister int		c;
X/*
X * If c is a letter, scan the id.  if it's #defined, expand it and scan
X * the next character and try again.
X *
X * Else, return the character.  If type[c] is a LET, the token is in token.
X */
X{
X	register DEFBUF	*dp;
X
X	if (infile != NULL && infile->fp != NULL)
X	    recursion = 0;
X	while (type[c] == LET && (dp = lookid(c)) != NULL) {
X	    expand(dp);
X	    c = get();
X	}
X	return (c);
X}
X
Xint
Xcatenate()
X/*
X * A token was just read (via macroid).
X * If the next character is TOK_SEP, concatenate the next token
X * return TRUE -- which should recall macroid after refreshing
X * macroid's argument.  If it is not TOK_SEP, unget() the character
X * and return FALSE.
X */
X{
X	register int		c;
X	register char		*token1;
X
X#if OK_CONCAT
X	if (get() != TOK_SEP) {			/* Token concatenation	*/
X	    unget();
X	    return (FALSE);
X	}
X	else {
X	    token1 = savestring(token);		/* Save first token	*/
X	    c = macroid(get());			/* Scan next token	*/
X	    switch(type[c]) {			/* What was it?		*/
X	    case LET:				/* An identifier, ...	*/
X		if (strlen(token1) + strlen(token) >= NWORK)
X		    cfatal("work buffer overflow doing %s #", token1);
X		sprintf(work, "%s%s", token1, token);
X		break;
X
X	    case DIG:				/* A digit string	*/
X		strcpy(work, token1);
X		workp = work + strlen(work);
X		do {
X		    save(c);
X		} while ((c = get()) != TOK_SEP);
X		/*
X		 * The trailing TOK_SEP is no longer needed.
X		 */
X		save(EOS);
X		break;
X
X	    default:				/* An error, ...	*/
X		if (isprint(c))
X		    cierror("Strange character '%c' after #", c);
X		else
X		    cierror("Strange character (%d.) after #", c);
X		strcpy(work, token1);
X		unget();
X		break;
X	    }
X	    /*
X	     * work has the concatenated token and token1 has
X	     * the first token (no longer needed).  Unget the
X	     * new (concatenated) token after freeing token1.
X	     * Finally, setup to read the new token.
X	     */
X	    free(token1);			/* Free up memory	*/
X	    ungetstring(work);			/* Unget the new thing,	*/
X	    return (TRUE);
X	}
X#else
X	return (FALSE);				/* Not supported	*/
X#endif
X}
X
Xint
Xscanstring(delim, outfun)
Xregister int	delim;			/* ' or "			*/
Xint		(*outfun)();		/* Output function		*/
X/*
X * Scan off a string.  Warning if terminated by newline or EOF.
X * outfun() outputs the character -- to a buffer if in a macro.
X * TRUE if ok, FALSE if error.
X */
X{
X	register int		c;
X
X	instring = TRUE;		/* Don't strip comments		*/
X	(*outfun)(delim);
X	while ((c = get()) != delim
X	     && c != '\n'
X	     && c != EOF_CHAR) {
X	    (*outfun)(c);
X	    if (c == '\\')
X		(*outfun)(get());
X	}
X	instring = FALSE;
X	if (c == delim) {
X	    (*outfun)(c);
X	    return (TRUE);
X	}
X	else {
X	    cerror("Unterminated string", NULLST);
X	    unget();
X	    return (FALSE);
X	}
X}
X
Xscannumber(c, outfun)
Xregister int	c;				/* First char of number	*/
Xregister int	(*outfun)();			/* Output/store func	*/
X/*
X * Process a number.  We know that c is from 0 to 9 or dot.
X * Algorithm from Dave Conroy's Decus C.
X */
X{
X	register int	radix;			/* 8, 10, or 16		*/
X	int		expseen;		/* 'e' seen in floater	*/
X	int		signseen;		/* '+' or '-' seen	*/
X	int		octal89;		/* For bad octal test	*/
X	int		dotflag;		/* TRUE if '.' was seen	*/
X
X	expseen = FALSE;			/* No exponent seen yet	*/
X	signseen = TRUE;			/* No +/- allowed yet	*/
X	octal89 = FALSE;			/* No bad octal yet	*/
X	radix = 10;				/* Assume decimal	*/
X	if ((dotflag = (c == '.')) != FALSE) {	/* . something?		*/
X	    (*outfun)('.');			/* Always out the dot	*/
X	    if (type[(c = get())] != DIG) {	/* If not a float numb,	*/
X		unget();			/* Rescan strange char	*/
X		return;				/* All done for now	*/
X	    }
X	}					/* End of float test	*/
X	else if (c == '0') {			/* Octal or hex?	*/
X	    (*outfun)(c);			/* Stuff initial zero	*/
X	    radix = 8;				/* Assume it's octal	*/
X	    c = get();				/* Look for an 'x'	*/
X	    if (c == 'x' || c == 'X') {		/* Did we get one?	*/
X		radix = 16;			/* Remember new radix	*/
X		(*outfun)(c);			/* Stuff the 'x'	*/
X		c = get();			/* Get next character	*/
X	    }
X	}
X	for (;;) {				/* Process curr. char.	*/
X	    /*
X	     * Note that this algorithm accepts "012e4" and "03.4"
X	     * as legitimate floating-point numbers.
X	     */
X	    if (radix != 16 && (c == 'e' || c == 'E')) {
X		if (expseen)			/* Already saw 'E'?	*/
X		    break;			/* Exit loop, bad nbr.	*/
X		expseen = TRUE;			/* Set exponent seen	*/
X		signseen = FALSE;		/* We can read '+' now	*/
X		radix = 10;			/* Decimal exponent	*/
X	    }
X	    else if (radix != 16 && c == '.') {
X		if (dotflag)			/* Saw dot already?	*/
X		    break;			/* Exit loop, two dots	*/
X		dotflag = TRUE;			/* Remember the dot	*/
X		radix = 10;			/* Decimal fraction	*/
X	    }
X	    else if (c == '+' || c == '-') {	/* 1.0e+10		*/
X		if (signseen)			/* Sign in wrong place?	*/
X		    break;			/* Exit loop, not nbr.	*/
X		/* signseen = TRUE; */		/* Remember we saw it	*/
X	    }
X	    else {				/* Check the digit	*/
X		switch (c) {
X		case '8': case '9':		/* Sometimes wrong	*/
X		    octal89 = TRUE;		/* Do check later	*/
X		case '0': case '1': case '2': case '3':
X		case '4': case '5': case '6': case '7':
X		    break;			/* Always ok		*/
X
X		case 'a': case 'b': case 'c': case 'd': case 'e': case 'f':
X		case 'A': case 'B': case 'C': case 'D': case 'E': case 'F':
X		    if (radix == 16)		/* Alpha's are ok only 	*/
X			break;			/* if reading hex.	*/
X		default:			/* At number end	*/
X		    goto done;			/* Break from for loop	*/
X		}				/* End of switch	*/
X	    }					/* End general case	*/
X	    (*outfun)(c);			/* Accept the character	*/
X	    signseen = TRUE;			/* Don't read sign now	*/
X	    c = get();				/* Read another char	*/
X	}					/* End of scan loop	*/
X	/*
X	 * When we break out of the scan loop, c contains the first
X	 * character (maybe) not in the number.  If the number is an
X	 * integer, allow a trailing 'L' for long and/or a trailing 'U'
X	 * for unsigned.  If not those, push the trailing character back
X	 * on the input stream.  Floating point numbers accept a trailing
X	 * 'L' for "long double".
X	 */
Xdone:	if (dotflag || expseen) {		/* Floating point?	*/
X	    if (c == 'l' || c == 'L') {
X		(*outfun)(c);
X		c = get();			/* Ungotten later	*/
X	    }
X	}
X	else {					/* Else it's an integer	*/
X	    /*
X	     * We know that dotflag and expseen are both zero, now:
X	     * dotflag signals "saw 'L'", and
X	     * expseen signals "saw 'U'".
X	     */
X	    for (;;) {
X		switch (c) {
X		case 'l':
X		case 'L':
X		    if (dotflag)
X			goto nomore;
X		    dotflag = TRUE;
X		    break;
X
X		case 'u':
X		case 'U':
X		    if (expseen)
X			goto nomore;
X		    expseen = TRUE;
X		    break;
X
X		default:
X		    goto nomore;
X		}
X		(*outfun)(c);			/* Got 'L' or 'U'.	*/
X		c = get();			/* Look at next, too.	*/
X	    }
X	}
Xnomore:	unget();				/* Not part of a number	*/
X	if (octal89 && radix == 8)
X	    cwarn("Illegal digit in octal number", NULLST);
X}
X
Xsave(c)
Xregister int	c;
X{
X	if (workp >= &work[NWORK])
X	    cfatal("Work buffer overflow", NULLST);
X	else *workp++ = c;
X}
X
Xchar *
Xsavestring(text)
Xchar		*text;
X/*
X * Store a string into free memory.
X */
X{
X	register char	*result;
X
X	result = getmem(strlen(text) + 1);
X	strcpy(result, text);
X	return (result);
X}
X
XFILEINFO	*
Xgetfile(bufsize, name)
Xint		bufsize;		/* Line or define buffer size	*/
Xchar		*name;			/* File or macro name string	*/
X/*
X * Common FILEINFO buffer initialization for a new file or macro.
X */
X{
X	register FILEINFO	*file;
X	register int		size;
X
X	size = strlen(name);			/* File/macro name	*/
X	file = (FILEINFO *) getmem(sizeof (FILEINFO) + bufsize + size);
X	file->parent = infile;			/* Chain files together	*/
X	file->fp = NULL;			/* No file yet		*/
X	file->filename = savestring(name);	/* Save file/macro name	*/
X	file->progname = NULL;			/* No #line seen yet	*/
X	file->unrecur = 0;			/* No macro fixup	*/
X	file->bptr = file->buffer;		/* Initialize line ptr	*/
X	file->buffer[0] = EOS;			/* Force first read	*/
X	file->line = 0;				/* (Not used just yet)	*/
X	if (infile != NULL)			/* If #include file	*/
X	    infile->line = line;		/* Save current line	*/
X	infile = file;				/* New current file	*/
X	line = 1;				/* Note first line	*/
X	return (file);				/* All done.		*/
X}
X
Xchar *
Xgetmem(size)
Xint		size;
X/*
X * Get a block of free memory.
X */
X{
X	register char	*result;
X	extern char	*malloc();
X
X	if ((result = malloc((unsigned) size)) == NULL)
X	    cfatal("Out of memory", NULLST);
X	return (result);
X}
X
X/*
X *			C P P   S y m b o l   T a b l e s
X */
X
X/*
X * SBSIZE defines the number of hash-table slots for the symbol table.
X * It must be a power of 2.
X */
X#ifndef	SBSIZE
X#define	SBSIZE	64
X#endif
X#define	SBMASK	(SBSIZE - 1)
X#if (SBSIZE ^ SBMASK) != ((SBSIZE * 2) - 1)
X	<< error, SBSIZE must be a power of 2 >>
X#endif
X
Xstatic DEFBUF	*symtab[SBSIZE];	/* Symbol table queue headers	*/
X
XDEFBUF *
Xlookid(c)
Xint	c;				/* First character of token	*/
X/*
X * Look for the next token in the symbol table.  Returns token in "token".
X * If found, returns the table pointer;  Else returns NULL.
X */
X{
X	register int		nhash;
X	register DEFBUF		*dp;
X	register char		*np;
X	int			temp;
X	int			isrecurse;	/* For #define foo foo	*/
X
X	np = token;
X	nhash = 0;
X	if ((isrecurse = (c == DEF_MAGIC)))	/* If recursive macro	*/
X	    c = get();				/* hack, skip DEF_MAGIC	*/
X	do {
X	    if (np < &token[IDMAX]) {		/* token dim is IDMAX+1	*/
X		*np++ = c;			/* Store token byte	*/
X		nhash += c;			/* Update hash value	*/
X	    }
X	    c = get();				/* And get another byte	*/
X	} while (type[c] == LET || type[c] == DIG);
X	unget();				/* Rescan terminator	*/
X	*np = EOS;				/* Terminate token	*/
X	if (isrecurse)				/* Recursive definition	*/
X	    return (NULL);			/* undefined just now	*/
X	nhash += (np - token);			/* Fix hash value	*/
X	dp = symtab[nhash & SBMASK];		/* Starting bucket	*/
X	while (dp != (DEFBUF *) NULL) {		/* Search symbol table	*/
X	    if (dp->hash == nhash		/* Fast precheck	*/
X	     && (temp = strcmp(dp->name, token)) >= 0)
X		break;
X	    dp = dp->link;			/* Nope, try next one	*/
X	}
X	return ((temp == 0) ? dp : NULL);
X}
X
XDEFBUF *
Xdefendel(name, delete)
Xchar		*name;
Xint		delete;			/* TRUE to delete a symbol	*/
X/*
X * Enter this name in the lookup table (delete = FALSE)
X * or delete this name (delete = TRUE).
X * Returns a pointer to the define block (delete = FALSE)
X * Returns NULL if the symbol wasn't defined (delete = TRUE).
X */
X{
X	register DEFBUF		*dp;
X	register DEFBUF		**prevp;
X	register char		*np;
X	int			nhash;
X	int			temp;
X	int			size;
X
X	for (nhash = 0, np = name; *np != EOS;)
X	    nhash += *np++;
X	size = (np - name);
X	nhash += size;
X	prevp = &symtab[nhash & SBMASK];
X	while ((dp = *prevp) != (DEFBUF *) NULL) {
X	    if (dp->hash == nhash
X	     && (temp = strcmp(dp->name, name)) >= 0) {
X		if (temp > 0)
X		    dp = NULL;			/* Not found		*/
X		else {
X		    *prevp = dp->link;		/* Found, unlink and	*/
X		    if (dp->repl != NULL)	/* Free the replacement	*/
X			free(dp->repl);		/* if any, and then	*/
X		    free((char *) dp);		/* Free the symbol	*/
X		}
X		break;
X	    }
X	    prevp = &dp->link;
X	}
X	if (!delete) {
X	    dp = (DEFBUF *) getmem(sizeof (DEFBUF) + size);
X	    dp->link = *prevp;
X	    *prevp = dp;
X	    dp->hash = nhash;
X	    dp->repl = NULL;
X	    dp->nargs = 0;
X	    strcpy(dp->name, name);
X	}
X	return (dp);
X}
X
X#if DEBUG
X
Xdumpdef(why)
Xchar		*why;
X{
X	register DEFBUF		*dp;
X	register DEFBUF		**syp;
X
X	printf("CPP symbol table dump %s\n", why);
X	for (syp = symtab; syp < &symtab[SBSIZE]; syp++) {
X	    if ((dp = *syp) != (DEFBUF *) NULL) {
X		printf("symtab[%d]\n", (syp - symtab));
X		do {
X		    dumpadef((char *) NULL, dp);
X		} while ((dp = dp->link) != (DEFBUF *) NULL);
X	    }
X	}
X}
X
Xdumpadef(why, dp)
Xchar		*why;			/* Notation			*/
Xregister DEFBUF	*dp;
X{
X	register char		*cp;
X	register int		c;
X
X	printf(" \"%s\" [%d]", dp->name, dp->nargs);
X	if (why != NULL)
X	    printf(" (%s)", why);
X	if (dp->repl != NULL) {
X	    printf(" => ");
X	    for (cp = dp->repl; (c = *cp++ & 0xFF) != EOS;) {
X		if (c >= MAC_PARM && c <= (MAC_PARM + PAR_MAC))
X		    printf("<%d>", c - MAC_PARM);
X		else if (isprint(c) || c == '\n' || c == '\t')
X		    putchar(c);
X		else if (c < ' ')
X		    printf("<^%c>", c + '@');
X		else
X		    printf("<\\0%o>", c);
X	    }
X	}
X	else {
X	    printf(", no replacement.");
X	}
X	putchar('\n');
X}
X#endif
X
X/*
X *			G E T
X */
X
Xint
Xget()
X/*
X * Return the next character from a macro or the current file.
X * Handle end of file from #include files.
X */
X{
X	register int		c;
X	register FILEINFO	*file;
X	register int		popped;		/* Recursion fixup	*/
X
X	popped = 0;
Xget_from_file:
X	if ((file = infile) == NULL)
X	    return (EOF_CHAR);
Xnewline:
X#if 0
X	printf("get(%s), recursion %d, line %d, bptr = %d, buffer \"%s\"\n",
X	    file->filename, recursion, line,
X	    file->bptr - file->buffer, file->buffer);
X#endif
X	/*
X	 * Read a character from the current input line or macro.
X	 * At EOS, either finish the current macro (freeing temp.
X	 * storage) or read another line from the current input file.
X	 * At EOF, exit the current file (#include) or, at EOF from
X	 * the cpp input file, return EOF_CHAR to finish processing.
X	 */
X	if ((c = *file->bptr++ & 0xFF) == EOS) {
X	    /*
X	     * Nothing in current line or macro.  Get next line (if
X	     * input from a file), or do end of file/macro processing.
X	     * In the latter case, jump back to restart from the top.
X	     */
X	    if (file->fp == NULL) {		/* NULL if macro	*/
X		popped++;
X		recursion -= file->unrecur;
X		if (recursion < 0)
X		    recursion = 0;
X		infile = file->parent;		/* Unwind file chain	*/
X	    }
X	    else {				/* Else get from a file	*/
X		if ((file->bptr = fgets(file->buffer, NBUFF, file->fp))
X			!= NULL) {
X#if DEBUG
X		    if (debug > 1) {		/* Dump it to stdout	*/
X			printf("\n#line %d (%s), %s",
X			    line, file->filename, file->buffer);
X		    }
X#endif
X		    goto newline;		/* process the line	*/
X		}
X		else {
X		    fclose(file->fp);		/* Close finished file	*/
X		    if ((infile = file->parent) != NULL) {
X			/*
X			 * There is an "ungotten" newline in the current
X			 * infile buffer (set there by doinclude() in
X			 * cpp1.c).  Thus, we know that the mainline code
X			 * is skipping over blank lines and will do a
X			 * #line at its convenience.
X			 */
X			wrongline = TRUE;	/* Need a #line now	*/
X		    }
X		}
X	    }
X	    /*
X	     * Free up space used by the (finished) file or macro and
X	     * restart input from the parent file/macro, if any.
X	     */
X	    free(file->filename);		/* Free name and	*/
X	    if (file->progname != NULL)		/* if a #line was seen,	*/
X		free(file->progname);		/* free it, too.	*/
X	    free((char *) file);		/* Free file space	*/
X	    if (infile == NULL)			/* If at end of file	*/
X		return (EOF_CHAR);		/* Return end of file	*/
X	    line = infile->line; 		/* Reset line number	*/
X	    goto get_from_file;			/* Get from the top.	*/
X	}
X	/*
X	 * Common processing for the new character.
X	 */
X	if (c == DEF_MAGIC && file->fp != NULL)	/* Don't allow delete	*/
X	    goto newline;			/* from a file		*/
X	if (file->parent != NULL) {		/* Macro or #include	*/
X	    if (popped != 0)
X		file->parent->unrecur += popped;
X	    else {
X		recursion -= file->parent->unrecur;
X		if (recursion < 0)
X		    recursion = 0;
X		file->parent->unrecur = 0;
X	    }
X	}
X	if (c == '\n')				/* Maintain current	*/
X	    ++line;				/* line counter		*/
X	if (instring)				/* Strings just return	*/
X	    return (c);				/* the character.	*/
X	else if (c == '/') {			/* Comment?		*/
X	    instring = TRUE;			/* So get() won't loop	*/
X	    if ((c = get()) != '*') {		/* Next byte '*'?	*/
X		instring = FALSE;		/* Nope, no comment	*/
X		unget();			/* Push the char. back	*/
X		return ('/');			/* Return the slash	*/
X	    }
X	    if (keepcomments) {			/* If writing comments	*/
X		putchar('/');			/* Write out the	*/
X		putchar('*');			/*   initializer	*/
X	    }
X	    for (;;) {				/* Eat a comment	*/
X		c = get();
Xtest:		if (keepcomments && c != EOF_CHAR)
X		    cput(c);
X		switch (c) {
X		case EOF_CHAR:
X		    cerror("EOF in comment", NULLST);
X		    return (EOF_CHAR);
X
X		case '/':
X		    if ((c = get()) != '*')	/* Don't let comments	*/
X			goto test;		/* Nest.		*/
X#ifdef VERBOSE
X		    cwarn("Nested comments", NULLST);
X#endif
X						/* Fall into * stuff	*/
X		case '*':
X		    if ((c = get()) != '/')	/* If comment doesn't	*/
X			goto test;		/* end, look at next	*/
X		    instring = FALSE;		/* End of comment,	*/
X		    if (keepcomments) {		/* Put out the comment	*/
X			cput(c);		/* terminator, too	*/
X		    }
X		    /*
X		     * A comment is syntactically "whitespace" --
X		     * however, there are certain strange sequences
X		     * such as
X		     *		#define foo(x)	(something)
X		     *			foo|* comment *|(123)
X		     *       these are '/' ^           ^
X		     * where just returning space (or COM_SEP) will cause
X		     * problems.  This can be "fixed" by overwriting the
X		     * '/' in the input line buffer with ' ' (or COM_SEP)
X		     * but that may mess up an error message.
X		     * So, we peek ahead -- if the next character is
X		     * "whitespace" we just get another character, if not,
X		     * we modify the buffer.  All in the name of purity.
X		     */
X		    if (*file->bptr == '\n'
X		     || type[*file->bptr & 0xFF] == SPA)
X			goto newline;
X#if COMMENT_INVISIBLE
X		    /*
X		     * Return magic (old-fashioned) syntactic space.
X		     */
X		    return ((file->bptr[-1] = COM_SEP));
X#else
X		    return ((file->bptr[-1] = ' '));
X#endif
X
X		case '\n':			/* we'll need a #line	*/
X		    if (!keepcomments)
X			wrongline = TRUE;	/* later...		*/
X		default:			/* Anything else is	*/
X		    break;			/* Just a character	*/
X		}				/* End switch		*/
X	    }					/* End comment loop	*/
X	}					/* End if in comment	*/
X	else if (!inmacro && c == '\\') {	/* If backslash, peek 	*/
X	    if ((c = get()) == '\n') {		/* for a <nl>.  If so,	*/
X		wrongline = TRUE;
X		goto newline;
X	    }
X	    else {				/* Backslash anything	*/
X		unget();			/* Get it later		*/
X		return ('\\');			/* Return the backslash	*/
X	    }
X	}
X	else if (c == '\f' || c == VT)		/* Form Feed, Vertical	*/
X	    c = ' ';				/* Tab are whitespace	*/
X	return (c);				/* Just return the char	*/
X}
X
Xunget()
X/*
X * Backup the pointer to reread the last character.  Fatal error
X * (code bug) if we backup too far.  unget() may be called,
X * without problems, at end of file.  Only one character may
X * be ungotten.  If you need to unget more, call ungetstring().
X */
X{
X	register FILEINFO	*file;
X
X	if ((file = infile) == NULL)
X	    return;			/* Unget after EOF		*/
X	if (--file->bptr < file->buffer)
X	    cfatal("Too much pushback", NULLST);
X	if (*file->bptr == '\n')	/* Ungetting a newline?		*/
X	    --line;			/* Unget the line number, too	*/
X}
X
Xungetstring(text)
Xchar		*text;
X/*
X * Push a string back on the input stream.  This is done by treating
X * the text as if it were a macro.
X */
X{
X	register FILEINFO	*file;
X	extern FILEINFO		*getfile();
X
X	file = getfile(strlen(text) + 1, "");
X	strcpy(file->buffer, text);
X}
X
Xint
Xcget()
X/*
X * Get one character, absorb "funny space" after comments or
X * token concatenation
X */
X{
X	register int	c;
X
X	do {
X	    c = get();
X#if COMMENT_INVISIBLE
X	} while (c == TOK_SEP || c == COM_SEP);
X#else
X	} while (c == TOK_SEP);
X#endif
X	return (c);
X}
X
X/*
X * Error messages and other hacks.  The first byte of severity
X * is 'S' for string arguments and 'I' for int arguments.  This
X * is needed for portability with machines that have int's that
X * are shorter than  char *'s.
X */
X
Xstatic
Xdomsg(severity, format, arg)
Xchar		*severity;		/* "Error", "Warning", "Fatal"	*/
Xchar		*format;		/* Format for the error message	*/
Xchar		*arg;			/* Something for the message	*/
X/*
X * Print filenames, macro names, and line numbers for error messages.
X */
X{
X	register char		*tp;
X	register FILEINFO	*file;
X
X	fprintf(stderr, "%sline %d, %s: ", MSG_PREFIX, line, &severity[1]);
X	if (*severity == 'S')
X	    fprintf(stderr, format, arg);
X	else
X	    fprintf(stderr, format, (int) arg);
X	putc('\n', stderr);
X	if ((file = infile) == NULL)
X	    return;				/* At end of file	*/
X	if (file->fp != NULL) {
X	    tp = file->buffer;			/* Print current file	*/
X	    fprintf(stderr, "%s", tp);		/* name, making sure	*/
X	    if (tp[strlen(tp) - 1] != '\n')	/* there's a newline	*/
X		putc('\n', stderr);
X	}
X	while ((file = file->parent) != NULL) {	/* Print #includes, too	*/
X	    if (file->fp == NULL)
X		fprintf(stderr, "from macro %s\n", file->filename);
X	    else {
X		tp = file->buffer;
X		fprintf(stderr, "from file %s, line %d:\n%s",
X		    (file->progname != NULL)
X			? file->progname : file->filename,
X		    file->line, tp);
X		if (tp[strlen(tp) - 1] != '\n')
X		    putc('\n', stderr);
X	    }
X	}
X}
X
Xcerror(format, sarg)
Xchar		*format;
Xchar		*sarg;		/* Single string argument		*/
X/*
X * Print a normal error message, string argument.
X */
X{
X	domsg("SError", format, sarg);
X	errors++;
X}
X
Xcierror(format, narg)
Xchar		*format;
Xint		narg;		/* Single numeric argument		*/
X/*
X * Print a normal error message, numeric argument.
X */
X{
X	domsg("IError", format, (char *) narg);
X	errors++;
X}
X
Xcfatal(format, sarg)
Xchar		*format;
Xchar		*sarg;			/* Single string argument	*/
X/*
X * A real disaster
X */
X{
X	domsg("SFatal error", format, sarg);
X	exit(IO_ERROR);
X}
X
Xcwarn(format, sarg)
Xchar		*format;
Xchar		*sarg;			/* Single string argument	*/
X/*
X * A non-fatal error, string argument.
X */
X{
X	domsg("SWarning", format, sarg);
X}
X
Xciwarn(format, narg)
Xchar		*format;
Xint		narg;			/* Single numeric argument	*/
X/*
X * A non-fatal error, numeric argument.
X */
X{
X	domsg("IWarning", format, (char *) narg);
X}
X
X
X
END-of-cpp6.c
exit