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GCC Code Coverage Report

Directory:	./		Exec	Total	Coverage
File:	bin/ksh/expr.c	Lines:	164	262	62.6 %
Date:	2016-12-06	Branches:	100	187	53.5 %


/*	$OpenBSD: expr.c,v 1.32 2015/12/30 09:07:00 tedu Exp $	*/

/*
 * Korn expression evaluation
 */
/*
 * todo: better error handling: if in builtin, should be builtin error, etc.
 */

#include <ctype.h>
#include <limits.h>
#include <string.h>

#include "sh.h"

/* The order of these enums is constrained by the order of opinfo[] */
enum token {
	/* some (long) unary operators */
	O_PLUSPLUS = 0, O_MINUSMINUS,
	/* binary operators */
	O_EQ, O_NE,
	/* assignments are assumed to be in range O_ASN .. O_BORASN */
	O_ASN, O_TIMESASN, O_DIVASN, O_MODASN, O_PLUSASN, O_MINUSASN,
	O_LSHIFTASN, O_RSHIFTASN, O_BANDASN, O_BXORASN, O_BORASN,
	O_LSHIFT, O_RSHIFT,
	O_LE, O_GE, O_LT, O_GT,
	O_LAND,
	O_LOR,
	O_TIMES, O_DIV, O_MOD,
	O_PLUS, O_MINUS,
	O_BAND,
	O_BXOR,
	O_BOR,
	O_TERN,
	O_COMMA,
	/* things after this aren't used as binary operators */
	/* unary that are not also binaries */
	O_BNOT, O_LNOT,
	/* misc */
	OPEN_PAREN, CLOSE_PAREN, CTERN,
	/* things that don't appear in the opinfo[] table */
	VAR, LIT, END, BAD
};
#define IS_BINOP(op) (((int)op) >= (int)O_EQ && ((int)op) <= (int)O_COMMA)
#define IS_ASSIGNOP(op)	((int)(op) >= (int)O_ASN && (int)(op) <= (int)O_BORASN)

enum prec {
	P_PRIMARY = 0,		/* VAR, LIT, (), ~ ! - + */
	P_MULT,			/* * / % */
	P_ADD,			/* + - */
	P_SHIFT,		/* << >> */
	P_RELATION,		/* < <= > >= */
	P_EQUALITY,		/* == != */
	P_BAND,			/* & */
	P_BXOR,			/* ^ */
	P_BOR,			/* | */
	P_LAND,			/* && */
	P_LOR,			/* || */
	P_TERN,			/* ?: */
	P_ASSIGN,		/* = *= /= %= += -= <<= >>= &= ^= |= */
	P_COMMA			/* , */
};
#define MAX_PREC	P_COMMA

struct opinfo {
	char		name[4];
	int		len;	/* name length */
	enum prec	prec;	/* precedence: lower is higher */
};

/* Tokens in this table must be ordered so the longest are first
 * (eg, += before +).  If you change something, change the order
 * of enum token too.
 */
static const struct opinfo opinfo[] = {
	{ "++",	 2, P_PRIMARY },	/* before + */
	{ "--",	 2, P_PRIMARY },	/* before - */
	{ "==",	 2, P_EQUALITY },	/* before = */
	{ "!=",	 2, P_EQUALITY },	/* before ! */
	{ "=",	 1, P_ASSIGN },		/* keep assigns in a block */
	{ "*=",	 2, P_ASSIGN },
	{ "/=",	 2, P_ASSIGN },
	{ "%=",	 2, P_ASSIGN },
	{ "+=",	 2, P_ASSIGN },
	{ "-=",	 2, P_ASSIGN },
	{ "<<=", 3, P_ASSIGN },
	{ ">>=", 3, P_ASSIGN },
	{ "&=",	 2, P_ASSIGN },
	{ "^=",	 2, P_ASSIGN },
	{ "|=",	 2, P_ASSIGN },
	{ "<<",	 2, P_SHIFT },
	{ ">>",	 2, P_SHIFT },
	{ "<=",	 2, P_RELATION },
	{ ">=",	 2, P_RELATION },
	{ "<",	 1, P_RELATION },
	{ ">",	 1, P_RELATION },
	{ "&&",	 2, P_LAND },
	{ "||",	 2, P_LOR },
	{ "*",	 1, P_MULT },
	{ "/",	 1, P_MULT },
	{ "%",	 1, P_MULT },
	{ "+",	 1, P_ADD },
	{ "-",	 1, P_ADD },
	{ "&",	 1, P_BAND },
	{ "^",	 1, P_BXOR },
	{ "|",	 1, P_BOR },
	{ "?",	 1, P_TERN },
	{ ",",	 1, P_COMMA },
	{ "~",	 1, P_PRIMARY },
	{ "!",	 1, P_PRIMARY },
	{ "(",	 1, P_PRIMARY },
	{ ")",	 1, P_PRIMARY },
	{ ":",	 1, P_PRIMARY },
	{ "",	 0, P_PRIMARY } /* end of table */
};


typedef struct expr_state Expr_state;
struct expr_state {
	const char *expression;		/* expression being evaluated */
	const char *tokp;		/* lexical position */
	enum token  tok;		/* token from token() */
	int	    noassign;		/* don't do assigns (for ?:,&&,||) */
	bool	    arith;		/* true if evaluating an $(())
					 * expression
					 */
	struct tbl *val;		/* value from token() */
	struct tbl *evaling;		/* variable that is being recursively
					 * expanded (EXPRINEVAL flag set)
					 */
};

enum error_type {
	ET_UNEXPECTED, ET_BADLIT, ET_RECURSIVE,
	ET_LVALUE, ET_RDONLY, ET_STR
};

static void	   evalerr(Expr_state *, enum error_type, const char *)
		    __attribute__((__noreturn__));
static struct tbl *evalexpr(Expr_state *, enum prec);
static void	   token(Expr_state *);
static struct tbl *do_ppmm(Expr_state *, enum token, struct tbl *, bool);
static void	   assign_check(Expr_state *, enum token, struct tbl *);
static struct tbl *tempvar(void);
static struct tbl *intvar(Expr_state *, struct tbl *);

/*
 * parse and evaluate expression
 */
int
evaluate(const char *expr, long int *rval, int error_ok, bool arith)
{
	struct tbl v;
	int ret;

	v.flag = DEFINED|INTEGER;
	v.type = 0;
	ret = v_evaluate(&v, expr, error_ok, arith);
	*rval = v.val.i;
	return ret;
}

/*
 * parse and evaluate expression, storing result in vp.
 */
int
v_evaluate(struct tbl *vp, const char *expr, volatile int error_ok,
    bool arith)
{
	struct tbl *v;
	Expr_state curstate;
	Expr_state * const es = &curstate;
	int i;

	/* save state to allow recursive calls */
	curstate.expression = curstate.tokp = expr;
	curstate.noassign = 0;
	curstate.arith = arith;
	curstate.evaling = NULL;
	curstate.val = NULL;

	newenv(E_ERRH);
	i = sigsetjmp(genv->jbuf, 0);
	if (i) {
		/* Clear EXPRINEVAL in of any variables we were playing with */
		if (curstate.evaling)
			curstate.evaling->flag &= ~EXPRINEVAL;
		quitenv(NULL);
		if (i == LAEXPR) {
			if (error_ok == KSH_RETURN_ERROR)
				return 0;
			errorf(NULL);
		}
		unwind(i);
		/* NOTREACHED */
	}

	token(es);
#if 1 /* ifdef-out to disallow empty expressions to be treated as 0 */
	if (es->tok == END) {
		es->tok = LIT;
		es->val = tempvar();
	}
#endif /* 0 */
	v = intvar(es, evalexpr(es, MAX_PREC));

	if (es->tok != END)
		evalerr(es, ET_UNEXPECTED, NULL);

	if (vp->flag & INTEGER)
		setint_v(vp, v, es->arith);
	else
		/* can fail if readonly */
		setstr(vp, str_val(v), error_ok);

	quitenv(NULL);

	return 1;
}

static void
evalerr(Expr_state *es, enum error_type type, const char *str)
{
	char tbuf[2];
	const char *s;

	es->arith = false;
	switch (type) {
	case ET_UNEXPECTED:
		switch (es->tok) {
		case VAR:
			s = es->val->name;
			break;
		case LIT:
			s = str_val(es->val);
			break;
		case END:
			s = "end of expression";
			break;
		case BAD:
			tbuf[0] = *es->tokp;
			tbuf[1] = '\0';
			s = tbuf;
			break;
		default:
			s = opinfo[(int)es->tok].name;
		}
		warningf(true, "%s: unexpected `%s'", es->expression, s);
		break;

	case ET_BADLIT:
		warningf(true, "%s: bad number `%s'", es->expression, str);
		break;

	case ET_RECURSIVE:
		warningf(true, "%s: expression recurses on parameter `%s'",
		    es->expression, str);
		break;

	case ET_LVALUE:
		warningf(true, "%s: %s requires lvalue",
		    es->expression, str);
		break;

	case ET_RDONLY:
		warningf(true, "%s: %s applied to read only variable",
		    es->expression, str);
		break;

	default: /* keep gcc happy */
	case ET_STR:
		warningf(true, "%s: %s", es->expression, str);
		break;
	}
	unwind(LAEXPR);
}

static struct tbl *
evalexpr(Expr_state *es, enum prec prec)
{
	struct tbl *vl, *vr = NULL, *vasn;
	enum token op;
	long res = 0;

	if (prec == P_PRIMARY) {
		op = es->tok;
		if (op == O_BNOT || op == O_LNOT || op == O_MINUS ||
		    op == O_PLUS) {
			token(es);
			vl = intvar(es, evalexpr(es, P_PRIMARY));
			if (op == O_BNOT)
				vl->val.i = ~vl->val.i;
			else if (op == O_LNOT)
				vl->val.i = !vl->val.i;
			else if (op == O_MINUS)
				vl->val.i = -vl->val.i;
			/* op == O_PLUS is a no-op */
		} else if (op == OPEN_PAREN) {
			token(es);
			vl = evalexpr(es, MAX_PREC);
			if (es->tok != CLOSE_PAREN)
				evalerr(es, ET_STR, "missing )");
			token(es);
		} else if (op == O_PLUSPLUS || op == O_MINUSMINUS) {
			token(es);
			vl = do_ppmm(es, op, es->val, true);
			token(es);
		} else if (op == VAR || op == LIT) {
			vl = es->val;
			token(es);
		} else {
			evalerr(es, ET_UNEXPECTED, NULL);
			/* NOTREACHED */
		}
		if (es->tok == O_PLUSPLUS || es->tok == O_MINUSMINUS) {
			vl = do_ppmm(es, es->tok, vl, false);
			token(es);
		}
		return vl;
	}
	vl = evalexpr(es, ((int) prec) - 1);
	for (op = es->tok; IS_BINOP(op) && opinfo[(int) op].prec == prec;
	    op = es->tok) {
		token(es);
		vasn = vl;
		if (op != O_ASN) /* vl may not have a value yet */
			vl = intvar(es, vl);
		if (IS_ASSIGNOP(op)) {
			assign_check(es, op, vasn);
			vr = intvar(es, evalexpr(es, P_ASSIGN));
		} else if (op != O_TERN && op != O_LAND && op != O_LOR)
			vr = intvar(es, evalexpr(es, ((int) prec) - 1));
		if ((op == O_DIV || op == O_MOD || op == O_DIVASN ||
		    op == O_MODASN) && vr->val.i == 0) {
			if (es->noassign)
				vr->val.i = 1;
			else
				evalerr(es, ET_STR, "zero divisor");
		}
		switch ((int) op) {
		case O_TIMES:
		case O_TIMESASN:
			res = vl->val.i * vr->val.i;
			break;
		case O_DIV:
		case O_DIVASN:
			if (vl->val.i == LONG_MIN && vr->val.i == -1)
				res = LONG_MIN;
			else
				res = vl->val.i / vr->val.i;
			break;
		case O_MOD:
		case O_MODASN:
			if (vl->val.i == LONG_MIN && vr->val.i == -1)
				res = 0;
			else
				res = vl->val.i % vr->val.i;
			break;
		case O_PLUS:
		case O_PLUSASN:
			res = vl->val.i + vr->val.i;
			break;
		case O_MINUS:
		case O_MINUSASN:
			res = vl->val.i - vr->val.i;
			break;
		case O_LSHIFT:
		case O_LSHIFTASN:
			res = vl->val.i << vr->val.i;
			break;
		case O_RSHIFT:
		case O_RSHIFTASN:
			res = vl->val.i >> vr->val.i;
			break;
		case O_LT:
			res = vl->val.i < vr->val.i;
			break;
		case O_LE:
			res = vl->val.i <= vr->val.i;
			break;
		case O_GT:
			res = vl->val.i > vr->val.i;
			break;
		case O_GE:
			res = vl->val.i >= vr->val.i;
			break;
		case O_EQ:
			res = vl->val.i == vr->val.i;
			break;
		case O_NE:
			res = vl->val.i != vr->val.i;
			break;
		case O_BAND:
		case O_BANDASN:
			res = vl->val.i & vr->val.i;
			break;
		case O_BXOR:
		case O_BXORASN:
			res = vl->val.i ^ vr->val.i;
			break;
		case O_BOR:
		case O_BORASN:
			res = vl->val.i | vr->val.i;
			break;
		case O_LAND:
			if (!vl->val.i)
				es->noassign++;
			vr = intvar(es, evalexpr(es, ((int) prec) - 1));
			res = vl->val.i && vr->val.i;
			if (!vl->val.i)
				es->noassign--;
			break;
		case O_LOR:
			if (vl->val.i)
				es->noassign++;
			vr = intvar(es, evalexpr(es, ((int) prec) - 1));
			res = vl->val.i || vr->val.i;
			if (vl->val.i)
				es->noassign--;
			break;
		case O_TERN:
			{
				int e = vl->val.i != 0;

				if (!e)
					es->noassign++;
				vl = evalexpr(es, MAX_PREC);
				if (!e)
					es->noassign--;
				if (es->tok != CTERN)
					evalerr(es, ET_STR, "missing :");
				token(es);
				if (e)
					es->noassign++;
				vr = evalexpr(es, P_TERN);
				if (e)
					es->noassign--;
				vl = e ? vl : vr;
			}
			break;
		case O_ASN:
			res = vr->val.i;
			break;
		case O_COMMA:
			res = vr->val.i;
			break;
		}
		if (IS_ASSIGNOP(op)) {
			vr->val.i = res;
			if (vasn->flag & INTEGER)
				setint_v(vasn, vr, es->arith);
			else
				setint(vasn, res);
			vl = vr;
		} else if (op != O_TERN)
			vl->val.i = res;
	}
	return vl;
}

static void
token(Expr_state *es)
{
	const char *cp;
	int c;
	char *tvar;

	/* skip white space */
	for (cp = es->tokp; (c = *cp), isspace((unsigned char)c); cp++)
		;
	es->tokp = cp;

	if (c == '\0')
		es->tok = END;
	else if (letter(c)) {
		for (; letnum(c); c = *cp)
			cp++;
		if (c == '[') {
			int len;

			len = array_ref_len(cp);
			if (len == 0)
				evalerr(es, ET_STR, "missing ]");
			cp += len;
		} else if (c == '(' /*)*/ ) {
			/* todo: add math functions (all take single argument):
			 * abs acos asin atan cos cosh exp int log sin sinh sqrt
			 * tan tanh
			 */
			;
		}
		if (es->noassign) {
			es->val = tempvar();
			es->val->flag |= EXPRLVALUE;
		} else {
			tvar = str_nsave(es->tokp, cp - es->tokp, ATEMP);
			es->val = global(tvar);
			afree(tvar, ATEMP);
		}
		es->tok = VAR;
	} else if (digit(c)) {
		for (; c != '_' && (letnum(c) || c == '#'); c = *cp++)
			;
		tvar = str_nsave(es->tokp, --cp - es->tokp, ATEMP);
		es->val = tempvar();
		es->val->flag &= ~INTEGER;
		es->val->type = 0;
		es->val->val.s = tvar;
		if (setint_v(es->val, es->val, es->arith) == NULL)
			evalerr(es, ET_BADLIT, tvar);
		afree(tvar, ATEMP);
		es->tok = LIT;
	} else {
		int i, n0;

		for (i = 0; (n0 = opinfo[i].name[0]); i++)
			if (c == n0 &&
			    strncmp(cp, opinfo[i].name, opinfo[i].len) == 0) {
				es->tok = (enum token) i;
				cp += opinfo[i].len;
				break;
			}
		if (!n0)
			es->tok = BAD;
	}
	es->tokp = cp;
}

/* Do a ++ or -- operation */
static struct tbl *
do_ppmm(Expr_state *es, enum token op, struct tbl *vasn, bool is_prefix)
{
	struct tbl *vl;
	int oval;

	assign_check(es, op, vasn);

	vl = intvar(es, vasn);
	oval = op == O_PLUSPLUS ? vl->val.i++ : vl->val.i--;
	if (vasn->flag & INTEGER)
		setint_v(vasn, vl, es->arith);
	else
		setint(vasn, vl->val.i);
	if (!is_prefix)		/* undo the inc/dec */
		vl->val.i = oval;

	return vl;
}

static void
assign_check(Expr_state *es, enum token op, struct tbl *vasn)
{
	if (es->tok == END || vasn == NULL ||
	    (vasn->name[0] == '\0' && !(vasn->flag & EXPRLVALUE)))
		evalerr(es, ET_LVALUE, opinfo[(int) op].name);
	else if (vasn->flag & RDONLY)
		evalerr(es, ET_RDONLY, opinfo[(int) op].name);
}

static struct tbl *
tempvar(void)
{
	struct tbl *vp;

	vp = alloc(sizeof(struct tbl), ATEMP);
	vp->flag = ISSET|INTEGER;
	vp->type = 0;
	vp->areap = ATEMP;
	vp->val.i = 0;
	vp->name[0] = '\0';
	return vp;
}

/* cast (string) variable to temporary integer variable */
static struct tbl *
intvar(Expr_state *es, struct tbl *vp)
{
	struct tbl *vq;

	/* try to avoid replacing a temp var with another temp var */
	if (vp->name[0] == '\0' &&
	    (vp->flag & (ISSET|INTEGER|EXPRLVALUE)) == (ISSET|INTEGER))
		return vp;

	vq = tempvar();
	if (setint_v(vq, vp, es->arith) == NULL) {
		if (vp->flag & EXPRINEVAL)
			evalerr(es, ET_RECURSIVE, vp->name);
		es->evaling = vp;
		vp->flag |= EXPRINEVAL;
		v_evaluate(vq, str_val(vp), KSH_UNWIND_ERROR, es->arith);
		vp->flag &= ~EXPRINEVAL;
		es->evaling = NULL;
	}
	return vq;
}


Generated by: GCOVR (Version 3.3)

Line	Branch	Exec	Source
1			/* $OpenBSD: expr.c,v 1.32 2015/12/30 09:07:00 tedu Exp $ */
2
3			/*
4			* Korn expression evaluation
5			*/
6			/*
7			* todo: better error handling: if in builtin, should be builtin error, etc.
8			*/
9
10			#include <ctype.h>
11			#include <limits.h>
12			#include <string.h>
13
14			#include "sh.h"
15
16			/* The order of these enums is constrained by the order of opinfo[] */
17			enum token {
18			/* some (long) unary operators */
19			O_PLUSPLUS = 0, O_MINUSMINUS,
20			/* binary operators */
21			O_EQ, O_NE,
22			/* assignments are assumed to be in range O_ASN .. O_BORASN */
23			O_ASN, O_TIMESASN, O_DIVASN, O_MODASN, O_PLUSASN, O_MINUSASN,
24			O_LSHIFTASN, O_RSHIFTASN, O_BANDASN, O_BXORASN, O_BORASN,
25			O_LSHIFT, O_RSHIFT,
26			O_LE, O_GE, O_LT, O_GT,
27			O_LAND,
28			O_LOR,
29			O_TIMES, O_DIV, O_MOD,
30			O_PLUS, O_MINUS,
31			O_BAND,
32			O_BXOR,
33			O_BOR,
34			O_TERN,
35			O_COMMA,
36			/* things after this aren't used as binary operators */
37			/* unary that are not also binaries */
38			O_BNOT, O_LNOT,
39			/* misc */
40			OPEN_PAREN, CLOSE_PAREN, CTERN,
41			/* things that don't appear in the opinfo[] table */
42			VAR, LIT, END, BAD
43			};
44			#define IS_BINOP(op) (((int)op) >= (int)O_EQ && ((int)op) <= (int)O_COMMA)
45			#define IS_ASSIGNOP(op) ((int)(op) >= (int)O_ASN && (int)(op) <= (int)O_BORASN)
46
47			enum prec {
48			P_PRIMARY = 0, /* VAR, LIT, (), ~ ! - + */
49			P_MULT, /* * / % */
50			P_ADD, /* + - */
51			P_SHIFT, /* << >> */
52			P_RELATION, /* < <= > >= */
53			P_EQUALITY, /* == != */
54			P_BAND, /* & */
55			P_BXOR, /* ^ */
56			P_BOR, /* \| */
57			P_LAND, /* && */
58			P_LOR, /* \|\| */
59			P_TERN, /* ?: */
60			P_ASSIGN, /* = = /= %= += -= <<= >>= &= ^= \|= /
61			P_COMMA /* , */
62			};
63			#define MAX_PREC P_COMMA
64
65			struct opinfo {
66			char name[4];
67			int len; /* name length */
68			enum prec prec; /* precedence: lower is higher */
69			};
70
71			/* Tokens in this table must be ordered so the longest are first
72			* (eg, += before +). If you change something, change the order
73			* of enum token too.
74			*/
75			static const struct opinfo opinfo[] = {
76			{ "++", 2, P_PRIMARY }, /* before + */
77			{ "--", 2, P_PRIMARY }, /* before - */
78			{ "==", 2, P_EQUALITY }, /* before = */
79			{ "!=", 2, P_EQUALITY }, /* before ! */
80			{ "=", 1, P_ASSIGN }, /* keep assigns in a block */
81			{ "*=", 2, P_ASSIGN },
82			{ "/=", 2, P_ASSIGN },
83			{ "%=", 2, P_ASSIGN },
84			{ "+=", 2, P_ASSIGN },
85			{ "-=", 2, P_ASSIGN },
86			{ "<<=", 3, P_ASSIGN },
87			{ ">>=", 3, P_ASSIGN },
88			{ "&=", 2, P_ASSIGN },
89			{ "^=", 2, P_ASSIGN },
90			{ "\|=", 2, P_ASSIGN },
91			{ "<<", 2, P_SHIFT },
92			{ ">>", 2, P_SHIFT },
93			{ "<=", 2, P_RELATION },
94			{ ">=", 2, P_RELATION },
95			{ "<", 1, P_RELATION },
96			{ ">", 1, P_RELATION },
97			{ "&&", 2, P_LAND },
98			{ "\|\|", 2, P_LOR },
99			{ "*", 1, P_MULT },
100			{ "/", 1, P_MULT },
101			{ "%", 1, P_MULT },
102			{ "+", 1, P_ADD },
103			{ "-", 1, P_ADD },
104			{ "&", 1, P_BAND },
105			{ "^", 1, P_BXOR },
106			{ "\|", 1, P_BOR },
107			{ "?", 1, P_TERN },
108			{ ",", 1, P_COMMA },
109			{ "~", 1, P_PRIMARY },
110			{ "!", 1, P_PRIMARY },
111			{ "(", 1, P_PRIMARY },
112			{ ")", 1, P_PRIMARY },
113			{ ":", 1, P_PRIMARY },
114			{ "", 0, P_PRIMARY } /* end of table */
115			};
116
117
118			typedef struct expr_state Expr_state;
119			struct expr_state {
120			const char expression; / expression being evaluated */
121			const char tokp; / lexical position */
122			enum token tok; /* token from token() */
123			int noassign; /* don't do assigns (for ?:,&&,\|\|) */
124			bool arith; /* true if evaluating an $(())
125			* expression
126			*/
127			struct tbl val; / value from token() */
128			struct tbl evaling; / variable that is being recursively
129			* expanded (EXPRINEVAL flag set)
130			*/
131			};
132
133			enum error_type {
134			ET_UNEXPECTED, ET_BADLIT, ET_RECURSIVE,
135			ET_LVALUE, ET_RDONLY, ET_STR
136			};
137
138			static void evalerr(Expr_state , enum error_type, const char )
139			__attribute__((__noreturn__));
140			static struct tbl evalexpr(Expr_state , enum prec);
141			static void token(Expr_state *);
142			static struct tbl do_ppmm(Expr_state , enum token, struct tbl *, bool);
143			static void assign_check(Expr_state , enum token, struct tbl );
144			static struct tbl *tempvar(void);
145			static struct tbl intvar(Expr_state , struct tbl *);
146
147			/*
148			* parse and evaluate expression
149			*/
150			int
151			evaluate(const char expr, long int rval, int error_ok, bool arith)
152		262	{
153			struct tbl v;
154			int ret;
155
156		262	v.flag = DEFINED\|INTEGER;
157		262	v.type = 0;
158		262	ret = v_evaluate(&v, expr, error_ok, arith);
159		262	*rval = v.val.i;
160		262	return ret;
161			}
162
163			/*
164			* parse and evaluate expression, storing result in vp.
165			*/
166			int
167			v_evaluate(struct tbl vp, const char expr, volatile int error_ok,
168			bool arith)
169		18021	{
170			struct tbl *v;
171			Expr_state curstate;
172		18021	Expr_state * const es = &curstate;
173			int i;
174
175			/* save state to allow recursive calls */
176		18021	curstate.expression = curstate.tokp = expr;
177		18021	curstate.noassign = 0;
178		18021	curstate.arith = arith;
179		18021	curstate.evaling = NULL;
180		18021	curstate.val = NULL;
181
182		18021	newenv(E_ERRH);
183		18021	i = sigsetjmp(genv->jbuf, 0);
184	✓✓	18033	if (i) {
185			/* Clear EXPRINEVAL in of any variables we were playing with */
186	✗✓	12	if (curstate.evaling)
187			curstate.evaling->flag &= ~EXPRINEVAL;
188		12	quitenv(NULL);
189	✓✗	12	if (i == LAEXPR) {
190	✗✓	12	if (error_ok == KSH_RETURN_ERROR)
191			return 0;
192		12	errorf(NULL);
193			}
194			unwind(i);
195			/* NOTREACHED */
196			}
197
198		18021	token(es);
199			#if 1 /* ifdef-out to disallow empty expressions to be treated as 0 */
200	✓✓	18015	if (es->tok == END) {
201		2	es->tok = LIT;
202		2	es->val = tempvar();
203			}
204			#endif /* 0 */
205		18015	v = intvar(es, evalexpr(es, MAX_PREC));
206
207	✗✓	18009	if (es->tok != END)
208			evalerr(es, ET_UNEXPECTED, NULL);
209
210	✓✗	18009	if (vp->flag & INTEGER)
211		18009	setint_v(vp, v, es->arith);
212			else
213			/* can fail if readonly */
214			setstr(vp, str_val(v), error_ok);
215
216		18009	quitenv(NULL);
217
218		18009	return 1;
219			}
220
221			static void
222			evalerr(Expr_state es, enum error_type type, const char str)
223		12	{
224			char tbuf[2];
225			const char *s;
226
227		12	es->arith = false;
228	✓✓✗✓ ✗✗	12	switch (type) {
229			case ET_UNEXPECTED:
230	✗✗✓✗ ✗	4	switch (es->tok) {
231			case VAR:
232			s = es->val->name;
233			break;
234			case LIT:
235			s = str_val(es->val);
236			break;
237			case END:
238		4	s = "end of expression";
239		4	break;
240			case BAD:
241			tbuf[0] = *es->tokp;
242			tbuf[1] = '\0';
243			s = tbuf;
244			break;
245			default:
246			s = opinfo[(int)es->tok].name;
247			}
248		4	warningf(true, "%s: unexpected `%s'", es->expression, s);
249		4	break;
250
251			case ET_BADLIT:
252		6	warningf(true, "%s: bad number `%s'", es->expression, str);
253		6	break;
254
255			case ET_RECURSIVE:
256			warningf(true, "%s: expression recurses on parameter `%s'",
257			es->expression, str);
258			break;
259
260			case ET_LVALUE:
261		2	warningf(true, "%s: %s requires lvalue",
262			es->expression, str);
263		2	break;
264
265			case ET_RDONLY:
266			warningf(true, "%s: %s applied to read only variable",
267			es->expression, str);
268			break;
269
270			default: /* keep gcc happy */
271			case ET_STR:
272			warningf(true, "%s: %s", es->expression, str);
273			break;
274			}
275		12	unwind(LAEXPR);
276			}
277
278			static struct tbl *
279			evalexpr(Expr_state *es, enum prec prec)
280		253236	{
281		253236	struct tbl vl, vr = NULL, *vasn;
282			enum token op;
283		253236	long res = 0;
284
285	✓✓	253236	if (prec == P_PRIMARY) {
286		18151	op = es->tok;
287	✓✓✗✓	18151	if (op == O_BNOT \|\| op == O_LNOT \|\| op == O_MINUS \|\|
288			op == O_PLUS) {
289		2	token(es);
290		2	vl = intvar(es, evalexpr(es, P_PRIMARY));
291	✓✗	2	if (op == O_BNOT)
292		2	vl->val.i = ~vl->val.i;
293			else if (op == O_LNOT)
294			vl->val.i = !vl->val.i;
295			else if (op == O_MINUS)
296			vl->val.i = -vl->val.i;
297			/* op == O_PLUS is a no-op */
298	✓✓	18149	} else if (op == OPEN_PAREN) {
299		12	token(es);
300		12	vl = evalexpr(es, MAX_PREC);
301	✗✓	12	if (es->tok != CLOSE_PAREN)
302			evalerr(es, ET_STR, "missing )");
303		12	token(es);
304	✗✓	18137	} else if (op == O_PLUSPLUS \|\| op == O_MINUSMINUS) {
305			token(es);
306			vl = do_ppmm(es, op, es->val, true);
307			token(es);
308	✓✓	18137	} else if (op == VAR \|\| op == LIT) {
309		18133	vl = es->val;
310		18133	token(es);
311			} else {
312		4	evalerr(es, ET_UNEXPECTED, NULL);
313			/* NOTREACHED */
314			}
315	✗✓	18147	if (es->tok == O_PLUSPLUS \|\| es->tok == O_MINUSMINUS) {
316			vl = do_ppmm(es, es->tok, vl, false);
317			token(es);
318			}
319		18147	return vl;
320			}
321		235085	vl = evalexpr(es, ((int) prec) - 1);
322	✓✓✓✓	470176	for (op = es->tok; IS_BINOP(op) && opinfo[(int) op].prec == prec;
323		106	op = es->tok) {
324		112	token(es);
325		112	vasn = vl;
326	✓✓	112	if (op != O_ASN) /* vl may not have a value yet */
327		98	vl = intvar(es, vl);
328	✓✓	112	if (IS_ASSIGNOP(op)) {
329		34	assign_check(es, op, vasn);
330		32	vr = intvar(es, evalexpr(es, P_ASSIGN));
331	✓✓✓✗	78	} else if (op != O_TERN && op != O_LAND && op != O_LOR)
332		66	vr = intvar(es, evalexpr(es, ((int) prec) - 1));
333	✓✓✗✓ ✗✓	106	if ((op == O_DIV \|\| op == O_MOD \|\| op == O_DIVASN \|\|
334			op == O_MODASN) && vr->val.i == 0) {
335			if (es->noassign)
336			vr->val.i = 1;
337			else
338			evalerr(es, ET_STR, "zero divisor");
339			}
340	✗✓✗✓ ✗✗✗✗ ✗✗✗✗ ✗✗✗✗ ✗✗✓✓ ✗✗	106	switch ((int) op) {
341			case O_TIMES:
342			case O_TIMESASN:
343			res = vl->val.i * vr->val.i;
344			break;
345			case O_DIV:
346			case O_DIVASN:
347	✗✓✗✗	4	if (vl->val.i == LONG_MIN && vr->val.i == -1)
348			res = LONG_MIN;
349			else
350		4	res = vl->val.i / vr->val.i;
351			break;
352			case O_MOD:
353			case O_MODASN:
354			if (vl->val.i == LONG_MIN && vr->val.i == -1)
355			res = 0;
356			else
357			res = vl->val.i % vr->val.i;
358			break;
359			case O_PLUS:
360			case O_PLUSASN:
361		76	res = vl->val.i + vr->val.i;
362		76	break;
363			case O_MINUS:
364			case O_MINUSASN:
365			res = vl->val.i - vr->val.i;
366			break;
367			case O_LSHIFT:
368			case O_LSHIFTASN:
369			res = vl->val.i << vr->val.i;
370			break;
371			case O_RSHIFT:
372			case O_RSHIFTASN:
373			res = vl->val.i >> vr->val.i;
374			break;
375			case O_LT:
376			res = vl->val.i < vr->val.i;
377			break;
378			case O_LE:
379			res = vl->val.i <= vr->val.i;
380			break;
381			case O_GT:
382			res = vl->val.i > vr->val.i;
383			break;
384			case O_GE:
385			res = vl->val.i >= vr->val.i;
386			break;
387			case O_EQ:
388			res = vl->val.i == vr->val.i;
389			break;
390			case O_NE:
391			res = vl->val.i != vr->val.i;
392			break;
393			case O_BAND:
394			case O_BANDASN:
395			res = vl->val.i & vr->val.i;
396			break;
397			case O_BXOR:
398			case O_BXORASN:
399			res = vl->val.i ^ vr->val.i;
400			break;
401			case O_BOR:
402			case O_BORASN:
403			res = vl->val.i \| vr->val.i;
404			break;
405			case O_LAND:
406			if (!vl->val.i)
407			es->noassign++;
408			vr = intvar(es, evalexpr(es, ((int) prec) - 1));
409			res = vl->val.i && vr->val.i;
410			if (!vl->val.i)
411			es->noassign--;
412			break;
413			case O_LOR:
414			if (vl->val.i)
415			es->noassign++;
416			vr = intvar(es, evalexpr(es, ((int) prec) - 1));
417			res = vl->val.i \|\| vr->val.i;
418			if (vl->val.i)
419			es->noassign--;
420			break;
421			case O_TERN:
422			{
423		12	int e = vl->val.i != 0;
424
425	✓✓	12	if (!e)
426		6	es->noassign++;
427		12	vl = evalexpr(es, MAX_PREC);
428	✓✓	12	if (!e)
429		6	es->noassign--;
430	✗✓	12	if (es->tok != CTERN)
431			evalerr(es, ET_STR, "missing :");
432		12	token(es);
433	✓✓	12	if (e)
434		6	es->noassign++;
435		12	vr = evalexpr(es, P_TERN);
436	✓✓	12	if (e)
437		6	es->noassign--;
438	✓✓	12	vl = e ? vl : vr;
439			}
440		12	break;
441			case O_ASN:
442		14	res = vr->val.i;
443		14	break;
444			case O_COMMA:
445			res = vr->val.i;
446			break;
447			}
448	✓✓	106	if (IS_ASSIGNOP(op)) {
449		32	vr->val.i = res;
450	✓✓	32	if (vasn->flag & INTEGER)
451		18	setint_v(vasn, vr, es->arith);
452			else
453		14	setint(vasn, res);
454		32	vl = vr;
455	✓✓	74	} else if (op != O_TERN)
456		62	vl->val.i = res;
457			}
458		235029	return vl;
459			}
460
461			static void
462			token(Expr_state *es)
463		36304	{
464			const char *cp;
465			int c;
466			char *tvar;
467
468			/* skip white space */
469	✓✓	72740	for (cp = es->tokp; (c = *cp), isspace((unsigned char)c); cp++)
470			;
471		36304	es->tokp = cp;
472
473	✓✓	36304	if (c == '\0')
474		18015	es->tok = END;
475	✓✓	18289	else if (letter(c)) {
476	✓✓✗✓	44	for (; letnum(c); c = *cp)
477		44	cp++;
478	✗✓	40	if (c == '[') {
479			int len;
480
481			len = array_ref_len(cp);
482			if (len == 0)
483			evalerr(es, ET_STR, "missing ]");
484			cp += len;
485			} else if (c == '(' /)/ ) {
486			/* todo: add math functions (all take single argument):
487			* abs acos asin atan cos cosh exp int log sin sinh sqrt
488			* tan tanh
489			*/
490			;
491			}
492	✓✓	40	if (es->noassign) {
493		8	es->val = tempvar();
494		8	es->val->flag \|= EXPRLVALUE;
495			} else {
496		32	tvar = str_nsave(es->tokp, cp - es->tokp, ATEMP);
497		32	es->val = global(tvar);
498		32	afree(tvar, ATEMP);
499			}
500		40	es->tok = VAR;
501	✓✓	18249	} else if (digit(c)) {
502	✓✗✗✓ ✓✓	57205	for (; c != '_' && (letnum(c) \|\| c == '#'); c = *cp++)
503			;
504		18099	tvar = str_nsave(es->tokp, --cp - es->tokp, ATEMP);
505		18099	es->val = tempvar();
506		18099	es->val->flag &= ~INTEGER;
507		18099	es->val->type = 0;
508		18099	es->val->val.s = tvar;
509	✓✓	18099	if (setint_v(es->val, es->val, es->arith) == NULL)
510		6	evalerr(es, ET_BADLIT, tvar);
511		18093	afree(tvar, ATEMP);
512		18093	es->tok = LIT;
513			} else {
514			int i, n0;
515
516	✓✗	3808	for (i = 0; (n0 = opinfo[i].name[0]); i++)
517	✓✓✓✓	3808	if (c == n0 &&
518			strncmp(cp, opinfo[i].name, opinfo[i].len) == 0) {
519		150	es->tok = (enum token) i;
520		150	cp += opinfo[i].len;
521		150	break;
522			}
523	✗✓	150	if (!n0)
524			es->tok = BAD;
525			}
526		36298	es->tokp = cp;
527		36298	}
528
529			/* Do a ++ or -- operation */
530			static struct tbl *
531			do_ppmm(Expr_state es, enum token op, struct tbl vasn, bool is_prefix)
532			{
533			struct tbl *vl;
534			int oval;
535
536			assign_check(es, op, vasn);
537
538			vl = intvar(es, vasn);
539			oval = op == O_PLUSPLUS ? vl->val.i++ : vl->val.i--;
540			if (vasn->flag & INTEGER)
541			setint_v(vasn, vl, es->arith);
542			else
543			setint(vasn, vl->val.i);
544			if (!is_prefix) /* undo the inc/dec */
545			vl->val.i = oval;
546
547			return vl;
548			}
549
550			static void
551			assign_check(Expr_state es, enum token op, struct tbl vasn)
552		34	{
553	✓✗✓✓ ✓✓	34	if (es->tok == END \|\| vasn == NULL \|\|
554			(vasn->name[0] == '\0' && !(vasn->flag & EXPRLVALUE)))
555		2	evalerr(es, ET_LVALUE, opinfo[(int) op].name);
556	✗✓	32	else if (vasn->flag & RDONLY)
557			evalerr(es, ET_RDONLY, opinfo[(int) op].name);
558		32	}
559
560			static struct tbl *
561			tempvar(void)
562		18133	{
563			struct tbl *vp;
564
565		18133	vp = alloc(sizeof(struct tbl), ATEMP);
566		18133	vp->flag = ISSET\|INTEGER;
567		18133	vp->type = 0;
568		18133	vp->areap = ATEMP;
569		18133	vp->val.i = 0;
570		18133	vp->name[0] = '\0';
571		18133	return vp;
572			}
573
574			/* cast (string) variable to temporary integer variable */
575			static struct tbl *
576			intvar(Expr_state es, struct tbl vp)
577		18203	{
578			struct tbl *vq;
579
580			/* try to avoid replacing a temp var with another temp var */
581	✓✓✓✓	18203	if (vp->name[0] == '\0' &&
582			(vp->flag & (ISSET\|INTEGER\|EXPRLVALUE)) == (ISSET\|INTEGER))
583		18179	return vp;
584
585		24	vq = tempvar();
586	✗✓	24	if (setint_v(vq, vp, es->arith) == NULL) {
587			if (vp->flag & EXPRINEVAL)
588			evalerr(es, ET_RECURSIVE, vp->name);
589			es->evaling = vp;
590			vp->flag \|= EXPRINEVAL;
591			v_evaluate(vq, str_val(vp), KSH_UNWIND_ERROR, es->arith);
592			vp->flag &= ~EXPRINEVAL;
593			es->evaling = NULL;
594			}
595		24	return vq;
596			}