/* C compiler: output functions */

#include "c.h"

static char buf1[4*1024], buf2[512];	/* output buffers */
static struct io {
	int fd;				/* file descriptor */
	char *bp;			/* buffer pointer */
	char *buffer;			/* buffer proper */
	char *limit;			/* high water limit */
} iob[] = {
	0, 0, 0, 0,
	1, buf1, buf1, buf1 + sizeof buf1 - 80,
	2, buf2, buf2, buf2 + sizeof buf2 - 80
}, *io[] = {
	&iob[0],			/* used by stringf */
	&iob[1],			/* standard output */
	&iob[2]				/* standard error & other files; used by fprint */
};
static int fd = 1;			/* current output file */

char *bp = buf1;			/* current output buffer pointer */

/* fprint - formatted output to file descriptor f */
#ifdef __STDC__
void fprint(int f, char *fmt, ...) {
#else
void fprint(f, fmt, va_alist) char *fmt; va_dcl {
#endif
	va_list ap;

	va_init(ap, fmt);
	vfprint(f, fmt, ap);
	va_end(ap);
}

/* outflush - flush output buffer; writes last buffer first */
void outflush() {
	struct io *iop = io[fd];

	assert(fd);
	if (bp > iop->buffer)
		write(iop->fd, iop->buffer, bp - iop->buffer);
	bp = iop->bp = iop->buffer;
}

/* outs - output string s */
void outs(s) char *s; {
	char *p;

	for (p = bp; *p = *s++; p++)
		;
	bp = p;
	if (bp > io[fd]->limit)
		outflush();
}

/* print - formatted output to standard output */
#ifdef __STDC__
void print(char *fmt, ...) {
#else
void print(fmt, va_alist) char *fmt; va_dcl {
#endif
	va_list ap;

	va_init(ap, fmt);
	vprint(fmt, ap);
	va_end(ap);
}

/* stringf - formatted output to a saved string */
#ifdef __STDC__
char *stringf(char *fmt, ...) {
#else
char *stringf(fmt, va_alist) char *fmt; va_dcl {
#endif
	char buf[MAXLINE];
	va_list ap;

	va_init(ap, fmt);
	fd = 0;
	io[1]->bp = bp;
	bp = io[0]->bp = io[0]->buffer = buf;
	io[0]->limit = buf + MAXLINE;
	vprint(fmt, ap);
	*bp = 0;
	bp = io[1]->bp;
	fd = 1;
	va_end(ap);
	return string(buf);
}

/* vfprint - formatted output to file descriptor f */
void vfprint(f, fmt, ap) char *fmt; va_list ap; {
	if (f == 1)
		vprint(fmt, ap);
	else {
		fd = 2;
		io[1]->bp = bp;
		io[2]->fd = f;
		bp = io[2]->bp;
		vprint(fmt, ap);
		outflush();
		bp = io[1]->bp;
		fd = 1;
	}
}

/* vprint - formatted output to standard output */
void vprint(fmt, ap) char *fmt; va_list ap; {
	char buf[40], *s;

	for (; *fmt; fmt++)
		if (*fmt == '%')
			switch (*++fmt) {
			case 'c':
				*bp++ = va_arg(ap, int);
				break;
			case 'd': {
				int n = va_arg(ap, int);
				unsigned m;
				s = buf + sizeof buf;
				*--s = 0;
				if (n == INT_MIN)
					m = (unsigned)INT_MAX + 1;
				else if (n < 0)
					m = -n;
				else
					m = n;
				do
					*--s = m%10 + '0';
				while (m /= 10);
				if (n < 0)
					*--s = '-';
				outs(s);
				break;
				}
			case 'k': {	/* print a token */
				int t = va_arg(ap, int);
				static char *tokens[] = {
#define xx(a,b,c,d,e,f,g) g,
#define yy xx
#include "token.h"
				};
				assert(tokens[t&0177]);
				outs(tokens[t&0177]);
				break;
				}
			case 'o': {
				unsigned n = va_arg(ap, unsigned);
				s = buf + sizeof buf;
				*--s = 0;
				do
					*--s = (n&7) + '0';
				while (n >>= 3);
				outs(s);
				break;
				}
			case 'x': {
				unsigned n = va_arg(ap, unsigned);
				s = buf + sizeof buf;
				*--s = 0;
				do
					*--s = "0123456789abcdef"[n&0xf];
				while (n >>= 4);
				outs(s);
				break;
				}
			case 's':
				s = va_arg(ap, char *);
				outs(s ? s : "");
				break;
			case 't': {	/* print a type */
				Type ty = va_arg(ap, Type);
				outtype(ty ? ty : voidtype);
				break;
				}
			case 'w': {	/* print a source coordinate */
				Coordinate *p = va_arg(ap, Coordinate *);
				if (p->file && *p->file)
					print("%s:", p->file);
				print("%d", p->y);
				break;
				}
			default:
				*bp++ = *fmt;
				break;
			}
		else if ((*bp++ = *fmt) == '\n' && bp > io[fd]->limit)
			outflush();
}