run.c

早期freebsd实现

void tfree(Cell *a)	/* free a tempcell */
{
	if (freeable(a))
		xfree(a->sval);
	if (a == tmps)
		ERROR "tempcell list is curdled" FATAL;
	a->cnext = tmps;
	tmps = a;
}

Cell *gettemp(void)	/* get a tempcell */
{	int i;
	register Cell *x;

	if (!tmps) {
		tmps = (Cell *) calloc(100, sizeof(Cell));
		if (!tmps)
			ERROR "out of space for temporaries" FATAL;
		for(i = 1; i < 100; i++)
			tmps[i-1].cnext = &tmps[i];
		tmps[i-1].cnext = 0;
	}
	x = tmps;
	tmps = x->cnext;
	*x = tempcell;
	return(x);
}

Cell *indirect(Node **a, int n)	/* $( a[0] ) */
{
	register Cell *x;
	register int m;
	register uchar *s;

	x = execute(a[0]);
	m = getfval(x);
	if (m == 0 && !is_a_number(s = getsval(x)))	/* suspicion! */
		ERROR "illegal field $(%s), name \"%s\"", s, x->nval FATAL;
  /* can x->nval ever be null??? */
		/* ERROR "illegal field $(%s)", s FATAL; */
	tempfree(x);
	x = fieldadr(m);
	x->ctype = OCELL;
	x->csub = CFLD;
	return(x);
}

Cell *substr(Node **a, int nnn)		/* substr(a[0], a[1], a[2]) */
{
	register int k, m, n;
	register uchar *s;
	int temp;
	register Cell *x, *y, *z;

	x = execute(a[0]);
	y = execute(a[1]);
	if (a[2] != 0)
		z = execute(a[2]);
	s = getsval(x);
	k = strlen(s) + 1;
	if (k <= 1) {
		tempfree(x);
		tempfree(y);
		if (a[2] != 0)
			tempfree(z);
		x = gettemp();
		setsval(x, "");
		return(x);
	}
	m = getfval(y);
	if (m <= 0)
		m = 1;
	else if (m > k)
		m = k;
	tempfree(y);
	if (a[2] != 0) {
		n = getfval(z);
		tempfree(z);
	} else
		n = k - 1;
	if (n < 0)
		n = 0;
	else if (n > k - m)
		n = k - m;
	dprintf( ("substr: m=%d, n=%d, s=%s\n", m, n, s) );
	y = gettemp();
	temp = s[n+m-1];	/* with thanks to John Linderman */
	s[n+m-1] = '\0';
	setsval(y, s + m - 1);
	s[n+m-1] = temp;
	tempfree(x);
	return(y);
}

Cell *sindex(Node **a, int nnn)		/* index(a[0], a[1]) */
{
	register Cell *x, *y, *z;
	register uchar *s1, *s2, *p1, *p2, *q;
	Awkfloat v = 0.0;

	x = execute(a[0]);
	s1 = getsval(x);
	y = execute(a[1]);
	s2 = getsval(y);

	z = gettemp();
	for (p1 = s1; *p1 != '\0'; p1++) {
		for (q=p1, p2=s2; *p2 != '\0' && *q == *p2; q++, p2++)
			;
		if (*p2 == '\0') {
			v = (Awkfloat) (p1 - s1 + 1);	/* origin 1 */
			break;
		}
	}
	tempfree(x);
	tempfree(y);
	setfval(z, v);
	return(z);
}

format(uchar *buf, int bufsize, uchar *s, Node *a)	/* printf-like conversions */
{
	uchar fmt[RECSIZE];
	register uchar *p, *t, *os;
	register Cell *x;
	int flag = 0, n;

	os = s;
	p = buf;
	while (*s) {
		if (p - buf >= bufsize)
			return -1;
		if (*s != '%') {
			*p++ = *s++;
			continue;
		}
		if (*(s+1) == '%') {
			*p++ = '%';
			s += 2;
			continue;
		}
		for (t=fmt; (*t++ = *s) != '\0'; s++) {
			if (isalpha(*s) && *s != 'l' && *s != 'h' && *s != 'L')
				break;	/* the ansi panoply */
			if (*s == '*') {
				x = execute(a);
				a = a->nnext;
				sprintf((char *)t-1, "%d", (int) getfval(x));
				t = fmt + strlen(fmt);
				tempfree(x);
			}
		}
		*t = '\0';
		if (t >= fmt + sizeof(fmt))
			ERROR "format item %.30s... too long", os FATAL;
		switch (*s) {
		case 'f': case 'e': case 'g': case 'E': case 'G':
			flag = 1;
			break;
		case 'd': case 'i':
			flag = 2;
			if(*(s-1) == 'l') break;
			*(t-1) = 'l';
			*t = 'd';
			*++t = '\0';
			break;
		case 'o': case 'x': case 'X': case 'u':
			flag = *(s-1) == 'l' ? 2 : 3;
			break;
		case 's':
			flag = 4;
			break;
		case 'c':
			flag = 5;
			break;
		default:
			ERROR "weird printf conversion %s", fmt WARNING;
			flag = 0;
			break;
		}
		if (a == NULL)
			ERROR "not enough args in printf(%s)", os FATAL;
		x = execute(a);
		a = a->nnext;
		switch (flag) {
		case 0:	sprintf((char *)p, "%s", fmt);	/* unknown, so dump it too */
			p += strlen(p);
			sprintf((char *)p, "%s", getsval(x));
			break;
		case 1:	sprintf((char *)p, (char *)fmt, getfval(x)); break;
		case 2:	sprintf((char *)p, (char *)fmt, (long) getfval(x)); break;
		case 3:	sprintf((char *)p, (char *)fmt, (int) getfval(x)); break;
		case 4:
			t = getsval(x);
			n = strlen(t);
			if (n >= bufsize)
				ERROR "huge string (%d chars) in printf %.30s...",
					n, t FATAL;
			sprintf((char *)p, (char *)fmt, t);
			break;
		case 5:
			isnum(x) ? sprintf((char *)p, (char *)fmt, (int) getfval(x))
				 : sprintf((char *)p, (char *)fmt, getsval(x)[0]);
			break;
		}
		tempfree(x);
		p += strlen(p);
		s++;
	}
	*p = '\0';
	for ( ; a; a = a->nnext)		/* evaluate any remaining args */
		execute(a);
	return 0;
}

Cell *asprintf(Node **a, int n)		/* sprintf(a[0]) */
{
	register Cell *x;
	register Node *y;
	uchar buf[3*RECSIZE];

	y = a[0]->nnext;
	x = execute(a[0]);
	if (format(buf, sizeof buf, getsval(x), y) == -1)
		ERROR "sprintf string %.30s... too long", buf FATAL;
	tempfree(x);
	x = gettemp();
	x->sval = tostring(buf);
	x->tval = STR;
	return(x);
}

Cell *aprintf(Node **a, int n)		/* printf */
{	/* a[0] is list of args, starting with format string */
	/* a[1] is redirection operator, a[2] is redirection file */
	FILE *fp;
	register Cell *x;
	register Node *y;
	uchar buf[3*RECSIZE];

	y = a[0]->nnext;
	x = execute(a[0]);
	if (format(buf, sizeof buf, getsval(x), y) == -1)
		ERROR "printf string %.30s... too long", buf FATAL;
	tempfree(x);
	if (a[1] == NULL) {
		fputs((char *)buf, stdout);
		if (ferror(stdout))
			ERROR "write error on stdout" FATAL;
	} else {
		fp = redirect((int)a[1], a[2]);
		fputs((char *)buf, fp);
		fflush(fp);
		if (ferror(fp))
			ERROR "write error on %s", filename(fp) FATAL;
	}
	return(true);
}

Cell *arith(Node **a, int n)	/* a[0] + a[1], etc.  also -a[0] */
{
	Awkfloat i, j;
	double v;
	register Cell *x, *y, *z;

	x = execute(a[0]);
	i = getfval(x);
	tempfree(x);
	if (n != UMINUS) {
		y = execute(a[1]);
		j = getfval(y);
		tempfree(y);
	}
	z = gettemp();
	switch (n) {
	case ADD:
		i += j;
		break;
	case MINUS:
		i -= j;
		break;
	case MULT:
		i *= j;
		break;
	case DIVIDE:
		if (j == 0)
			ERROR "division by zero" FATAL;
		i /= j;
		break;
	case MOD:
		if (j == 0)
			ERROR "division by zero in mod" FATAL;
		modf(i/j, &v);
		i = i - j * v;
		break;
	case UMINUS:
		i = -i;
		break;
	case POWER:
		if (j >= 0 && modf(j, &v) == 0.0)	/* pos integer exponent */
			i = ipow(i, (int) j);
		else
			i = errcheck(pow(i, j), "pow");
		break;
	default:	/* can't happen */
		ERROR "illegal arithmetic operator %d", n FATAL;
	}
	setfval(z, i);
	return(z);
}

double ipow(double x, int n)	/* x**n.  ought to be done by pow, but isn't always */
{
	double v;

	if (n <= 0)
		return 1;
	v = ipow(x, n/2);
	if (n % 2 == 0)
		return v * v;
	else
		return x * v * v;
}

Cell *incrdecr(Node **a, int n)		/* a[0]++, etc. */
{
	register Cell *x, *z;
	register int k;
	Awkfloat xf;

	x = execute(a[0]);
	xf = getfval(x);
	k = (n == PREINCR || n == POSTINCR) ? 1 : -1;
	if (n == PREINCR || n == PREDECR) {
		setfval(x, xf + k);
		return(x);
	}
	z = gettemp();
	setfval(z, xf);
	setfval(x, xf + k);
	tempfree(x);
	return(z);
}

Cell *assign(Node **a, int n)	/* a[0] = a[1], a[0] += a[1], etc. */
{		/* this is subtle; don't muck with it. */
	register Cell *x, *y;
	Awkfloat xf, yf;
	double v;

	y = execute(a[1]);
	x = execute(a[0]);
	if (n == ASSIGN) {	/* ordinary assignment */
		if (x == y && !(x->tval & (FLD|REC)))	/* self-assignment: */
			;		/* leave alone unless it's a field */
		else if ((y->tval & (STR|NUM)) == (STR|NUM)) {
			setsval(x, getsval(y));
			x->fval = getfval(y);
			x->tval |= NUM;
		}
		else if (y->tval & STR)
			setsval(x, getsval(y));
		else if (y->tval & NUM)
			setfval(x, getfval(y));
		else
			funnyvar(y, "read value of");
		tempfree(y);
		return(x);
	}
	xf = getfval(x);
	yf = getfval(y);
	switch (n) {
	case ADDEQ:
		xf += yf;
		break;
	case SUBEQ:
		xf -= yf;
		break;
	case MULTEQ:
		xf *= yf;
		break;
	case DIVEQ:
		if (yf == 0)
			ERROR "division by zero in /=" FATAL;
		xf /= yf;
		break;
	case MODEQ:
		if (yf == 0)
			ERROR "division by zero in %%=" FATAL;
		modf(xf/yf, &v);
		xf = xf - yf * v;
		break;
	case POWEQ:
		if (yf >= 0 && modf(yf, &v) == 0.0)	/* pos integer exponent */
			xf = ipow(xf, (int) yf);
		else
			xf = errcheck(pow(xf, yf), "pow");
		break;
	default:
		ERROR "illegal assignment operator %d", n FATAL;
		break;
	}
	tempfree(y);
	setfval(x, xf);
	return(x);
}

Cell *cat(Node **a, int q)	/* a[0] cat a[1] */
{
	register Cell *x, *y, *z;
	register int n1, n2;
	register uchar *s;

	x = execute(a[0]);
	y = execute(a[1]);
	getsval(x);
	getsval(y);
	n1 = strlen(x->sval);
	n2 = strlen(y->sval);
	s = (uchar *) malloc(n1 + n2 + 1);
	if (s == NULL)
		ERROR "out of space concatenating %.15s... and %.15s...",
			x->sval, y->sval FATAL;
	strcpy(s, x->sval);
	strcpy(s+n1, y->sval);
	tempfree(y);
	z = gettemp();
	z->sval = s;
	z->tval = STR;
	tempfree(x);
	return(z);
}

Cell *pastat(Node **a, int n)	/* a[0] { a[1] } */
{
	register Cell *x;

	if (a[0] == 0)
		x = execute(a[1]);
	else {
		x = execute(a[0]);
		if (istrue(x)) {
			tempfree(x);
			x = execute(a[1]);
		}
	}
	return x;
}

Cell *dopa2(Node **a, int n)	/* a[0], a[1] { a[2] } */
{
	register Cell *x;
	register int pair;

	pair = (int) a[3];
	if (pairstack[pair] == 0) {
		x = execute(a[0]);
		if (istrue(x))
			pairstack[pair] = 1;
		tempfree(x);
	}
	if (pairstack[pair] == 1) {
		x = execute(a[1]);
		if (istrue(x))
			pairstack[pair] = 0;
		tempfree(x);
		x = execute(a[2]);
		return(x);
	}
	return(false);
}

Cell *split(Node **a, int nnn)	/* split(a[0], a[1], a[2]); a[3] is type */
{
	Cell *x, *y, *ap;
	register uchar *s;
	register int sep;
	uchar *t, temp, num[10], *fs;
	int n, tempstat;

	y = execute(a[0]);	/* source string */
	s = getsval(y);
	if (a[2] == 0)		/* fs string */
		fs = *FS;
	else if ((int) a[3] == STRING) {	/* split(str,arr,"string") */
		x = execute(a[2]);
		fs = getsval(x);
	} else if ((int) a[3] == REGEXPR)
		fs = (uchar*) "(regexpr)";	/* split(str,arr,/regexpr/) */
	else
		ERROR "illegal type of split()" FATAL;
	sep = *fs;
	ap = execute(a[1]);	/* array name */
	freesymtab(ap);
	dprintf( ("split: s=|%s|, a=%s, sep=|%s|\n", s, ap->nval, fs) );
	ap->tval &= ~STR;
	ap->tval |= ARR;
	ap->sval = (uchar *) makesymtab(NSYMTAB);

	n = 0;
	if (*s != '\0' && strlen(fs) > 1 || (int) a[3] == REGEXPR) {	/* reg expr */
		fa *pfa;
		if ((int) a[3] == REGEXPR) {	/* it's ready already */
			pfa = (fa *) a[2];
		} else {
			pfa = makedfa(fs, 1);
		}
		if (nematch(pfa,s)) {
			tempstat = pfa->initstat;
			pfa->initstat = 2;
			do {
				n++;
				sprintf((char *)num, "%d", n);
				temp = *patbeg;
				*patbeg = '\0';
				if (is_a_number(s))
					setsymtab(num, s, atof((char *)s), STR|NUM, (Array *) ap->sval);
				else
					setsymtab(num, s, 0.0, STR, (Array *) ap->sval);
				*patbeg = temp;
				s = patbeg + patlen;
				if (*(patbeg+patlen-1) == 0 || *s == 0) {
					n++;
					sprintf((char *)num, "%d", n);
					setsymtab(num, "", 0.0, STR, (Array *) ap->sval);
					pfa->initstat = tempstat;
					goto spdone;
				}
			} while (nematch(pfa,s));
		}
		n++;
		sprintf((char *)num, "%d", n);
		if (is_a_number(s))
			setsymtab(num, s, atof((char *)s), STR|NUM, (Array *) ap->sval);
		else
			setsymtab(num, s, 0.0, STR, (Array *) ap->sval);
  spdone:
		pfa = NULL;
	} else if (sep == ' ') {
		for (n = 0; ; ) {
			while (*s == ' ' || *s == '\t' || *s == '\n')
				s++;
			if (*s == 0)
				break;
			n++;
			t = s;
			do
				s++;
			while (*s!=' ' && *s!='\t' && *s!='\n' && *s!='\0');
			temp = *s;
			*s = '\0';
			sprintf((char *)num, "%d", n);
			if (is_a_number(t))
				setsymtab(num, t, atof((char *)t), STR|NUM, (Array *) ap->sval);
			else
				setsymtab(num, t, 0.0, STR, (Array *) ap->sval);
			*s = temp;
			if (*s != 0)
				s++;
		}
	} else if (*s != 0) {
		for (;;) {
			n++;
			t = s;
			while (*s != sep && *s != '\n' && *s != '\0')
				s++;
			temp = *s;
			*s = '\0';
			sprintf((char *)num, "%d", n);
			if (is_a_number(t))
				setsymtab(num, t, atof((char *)t), STR|NUM, (Array *) ap->sval);
			else
				setsymtab(num, t, 0.0, STR, (Array *) ap->sval);
			*s = temp;
			if (*s++ == 0)
				break;
		}
	}
	tempfree(ap);
	tempfree(y);
	if (a[2] != 0 && (int) a[3] == STRING)
		tempfree(x);
	x = gettemp();
	x->tval = NUM;