/*  * This file is part of the UCB release of Plan 9. It is subject to the license * terms in the LICENSE file found in the top-level directory of this * distribution and at http://akaros.cs.berkeley.edu/files/Plan9License. No * part of the UCB release of Plan 9, including this file, may be copied, * modified, propagated, or distributed except according to the terms contained * in the LICENSE file. */ #include "a.h" /* * Section 1 - General Explanation. */ /* 1.3 - Numerical parameter input.  */char *units = "icPmnpuvx";intscale2units(char c){	int x;		switch(c){	case 'i':	/* inch */		return UPI;	case 'c':	/* centimeter */		return 0.3937008 * UPI;	case 'P':	/* pica = 1/6 inch */		return UPI / 6;	case 'm':	/* em = S points */		return UPI / 72.0 * getnr(L(".s"));	case 'n':	/* en = em/2 */		return UPI / 72.0 * getnr(L(".s")) / 2;	case 'p':	/* point = 1/72 inch */		return UPI / 72;	case 'u':	/* basic unit */		return 1;	case 'v':	/* vertical line space V */		x = getnr(L(".v"));		if(x == 0)			x = 12 * UPI / 72;		return x;	case 'x':	/* pixel (htmlroff addition) */		return UPX;	default:		return 1;	}} /* 1.4 - Numerical expressions. */int eval0(Rune**, int, int);inteval(Rune *s){	return eval0(&s, 1, 1);}longrunestrtol(Rune *a, Rune **p){	long n;		n = 0;	while('0' <= *a && *a <= '9'){		n = n*10 + *a-'0';		a++;	}	*p = a;	return n;} intevalscale(Rune *s, int c){	return eval0(&s, scale2units(c), 1);} inteval0(Rune **pline, int scale, int recur){	Rune *p;	int neg;	double f, p10;	int x, y; 	neg = 0;	p = *pline;	while(*p == '-'){		neg = 1 - neg;		p++;	}	if(*p == '('){		p++;		x = eval0(&p, scale, 1);		if (*p != ')'){			*pline = p;			return x;		}		p++;	}else{		f = runestrtol(p, &p);		if(*p == '.'){			p10 = 1.0;			p++;			while('0' <= *p && *p <= '9'){				p10 /= 10;				f += p10*(*p++ - '0');			}		}		if(*p && strchr(units, *p)){			if(scale)				f *= scale2units(*p);			p++;		}else if(scale)			f *= scale;		x = f;	}	if(neg)		x = -x;	if(!recur){		*pline = p;		return x;	}		while(*p){		switch(*p++) {		case '+':			x += eval0(&p, scale, 0);			continue;		case '-':			x -= eval0(&p, scale, 0);			continue;		case '*':			x *= eval0(&p, scale, 0);			continue;		case '/':			y = eval0(&p, scale, 0);			if (y == 0) {				fprint(2, "%L: divide by zero %S\n", p);				y = 1;			}			x /= y;			continue;		case '%':			y = eval0(&p, scale, 0);			if (!y) {				fprint(2, "%L: modulo by zero %S\n", p);				y = 1;			}			x %= y;			continue;		case '<':			if (*p == '=') {				p++;				x = x <= eval0(&p, scale, 0);				continue;			}			x = x < eval0(&p, scale, 0);			continue;		case '>':			if (*p == '=') {				p++;				x = x >= eval0(&p, scale, 0);				continue;			}			x = x > eval0(&p, scale, 0);			continue;		case '=':			if (*p == '=')				p++;			x = x == eval0(&p, scale, 0);			continue;		case '&':			x &= eval0(&p, scale, 0);			continue;		case ':':			x |= eval0(&p, scale, 0);			continue;		}	}	*pline = p;	return x;} voidt1init(void){	Tm tm;		tm = *localtime(time(0));	nr(L("dw"), tm.wday+1);	nr(L("dy"), tm.mday);	nr(L("mo"), tm.mon);	nr(L("yr"), tm.year%100);}