//ww:run
package main;

import io;
import memio;
import os;
import temp;

fn myseek(s: io.stream, off: io.off, w: io.whence) (io.off | io.error) = {
	return off + 100: io.off;
};

fn fresh() i32 = {
	let fd: i32 = -1;
	let path: str;
	match (temp.named(&fd, &path, "/tmp", temp.mode.RDWR, 0o600: i32)) {
	case void => void;
	case let e: os.oserror => return -1;
	};
	if (os.remove(path) != 0) { os.close(fd); return -1; };
	return fd;
};

export fn main() i32 = {
	let fd: i32 = fresh();
	if (fd < 0) { return 1; };
	let h: io.file = fd;
	let data: [3]u8;
	data[0] = 65u8; data[1] = 66u8; data[2] = 67u8;
	match (io.write(h, data[0:3])) {
	case let n: size => { if (n != 3: size) { io.close(h); return 2; }; };
	case let e: io.error => { io.close(h); return 3; };
	};
	match (io.seek(h, 0: io.off, io.whence.SET)) {
	case let o: io.off => { if (o != 0: io.off) { io.close(h); return 4; }; };
	case let e: io.error => { io.close(h); return 5; };
	};
	let rb: [3]u8;
	match (io.read(h, rb[0:3])) {
	case let n: size => { if (n != 3: size) { io.close(h); return 6; }; };
	case let z: io.eof => { io.close(h); return 7; };
	case let e: io.error => { io.close(h); return 8; };
	};
	if (rb[0] != 65u8 || rb[1] != 66u8 || rb[2] != 67u8) { io.close(h); return 9; };
	match (io.seek(h, 0: io.off, io.whence.END)) {
	case let o: io.off => { if (o != 3: io.off) { io.close(h); return 10; }; };
	case let e: io.error => { io.close(h); return 11; };
	};
	match (io.tell(h)) {
	case let o: io.off => { if (o != 3: io.off) { io.close(h); return 12; }; };
	case let e: io.error => { io.close(h); return 13; };
	};
	match (io.close(h)) {
	case void => void;
	case let e: io.error => return 14;
	};

	let sbuf: [8]u8;
	let st: memio.stream = memio.fixed(sbuf[0:8]);
	let s: io.stream = &st.vt;
	let sdata: [3]u8;
	sdata[0] = 88u8; sdata[1] = 89u8; sdata[2] = 90u8;
	match (io.write(s, sdata[0:3])) {
	case let n: size => { if (n != 3: size) { return 15; }; };
	case let e: io.error => return 16;
	};
	if (sbuf[0] != 88u8 || sbuf[1] != 89u8 || sbuf[2] != 90u8) { return 17; };
	let st2: memio.stream = memio.fixed(sbuf[0:8]);
	let s2: io.stream = &st2.vt;
	let srb: [3]u8;
	match (io.read(s2, srb[0:3])) {
	case let n: size => { if (n != 3: size) { return 18; }; };
	case let z: io.eof => return 19;
	case let e: io.error => return 20;
	};
	if (srb[0] != 88u8 || srb[1] != 89u8 || srb[2] != 90u8) { return 21; };

	let emptyvt: io.vtable;
	let noseek: io.stream = &emptyvt;
	match (io.seek(noseek, 0: io.off, io.whence.SET)) {
	case let o: io.off => return 22;
	case let e: io.error => void;
	};

	let seekvt: io.vtable;
	seekvt.seeker = (&myseek): *io.seeker;
	let seeker: io.stream = &seekvt;
	match (io.seek(seeker, 5: io.off, io.whence.SET)) {
	case let o: io.off => { if (o != 105: io.off) { return 23; }; };
	case let e: io.error => return 24;
	};
	match (io.tell(seeker)) {
	case let o: io.off => { if (o != 100: io.off) { return 25; }; };
	case let e: io.error => return 26;
	};

	let bad: io.file = -1i32;
	match (io.write(bad, data[0:3])) {
	case let n: size => return 27;
	case let e: io.error => void;
	};
	match (io.read(bad, data[0:3])) {
	case let n: size => return 28;
	case let z: io.eof => return 29;
	case let e: io.error => void;
	};
	match (io.seek(bad, 0: io.off, io.whence.SET)) {
	case let o: io.off => return 30;
	case let e: io.error => void;
	};
	match (io.close(bad)) {
	case void => return 31;
	case let e: io.error => void;
	};
	return 0;
};