1// Copyright 2011 The Go Authors. All rights reserved.
2// Use of this source code is governed by a BSD-style
3// license that can be found in the LICENSE file.
4
5//go:build unix || (js && wasm) || wasip1
6
7package time
8
9import (
10	"errors"
11	"runtime"
12	"syscall"
13)
14
15// for testing: whatever interrupts a sleep
16func interrupt() {
17	// There is no mechanism in wasi to interrupt the call to poll_oneoff
18	// used to implement runtime.usleep so this function does nothing, which
19	// somewhat defeats the purpose of TestSleep but we are still better off
20	// validating that time elapses when the process calls time.Sleep than
21	// skipping the test altogether.
22	if runtime.GOOS != "wasip1" {
23		syscall.Kill(syscall.Getpid(), syscall.SIGCHLD)
24	}
25}
26
27func open(name string) (uintptr, error) {
28	fd, err := syscall.Open(name, syscall.O_RDONLY, 0)
29	if err != nil {
30		return 0, err
31	}
32	return uintptr(fd), nil
33}
34
35func read(fd uintptr, buf []byte) (int, error) {
36	return syscall.Read(int(fd), buf)
37}
38
39func closefd(fd uintptr) {
40	syscall.Close(int(fd))
41}
42
43func preadn(fd uintptr, buf []byte, off int) error {
44	whence := seekStart
45	if off < 0 {
46		whence = seekEnd
47	}
48	if _, err := syscall.Seek(int(fd), int64(off), whence); err != nil {
49		return err
50	}
51	for len(buf) > 0 {
52		m, err := syscall.Read(int(fd), buf)
53		if m <= 0 {
54			if err == nil {
55				return errors.New("short read")
56			}
57			return err
58		}
59		buf = buf[m:]
60	}
61	return nil
62}
63