Function Pwritev

pkg/sentry/syscalls/linux/sys_read_write.go:410–436

Pwritev implements Linux syscall pwritev(2).

(t *kernel.Task, sysno uintptr, args arch.SyscallArguments)

// Pwritev implements Linux syscall pwritev(2).
func Pwritev(t *kernel.Task, sysno uintptr, args arch.SyscallArguments) (uintptr, *kernel.SyscallControl, error) {
	fd := args[0].Int()
	addr := args[1].Pointer()
	iovcnt := int(args[2].Int())
	offset := args[3].Int64()

	file := t.GetFile(fd)
	if file == nil {
		return 0, nil, linuxerr.EBADF
	}
	defer file.DecRef(t)

	// Check that the offset is legitimate.
	if offset < 0 {
		return 0, nil, linuxerr.EINVAL
	}

	// Get the source of the write.
	src, err := t.IovecsIOSequence(addr, iovcnt, usermem.IOOpts{})
	if err != nil {
		return 0, nil, err
	}

	n, err := pwrite(t, file, src, offset, vfs.WriteOptions{})
	t.IOUsage().AccountReadSyscall(n)
	return uintptr(n), nil, HandleIOError(t, n != 0, err, linuxerr.ERESTARTSYS, "pwritev", file)
}

// Pwritev2 implements Linux syscall pwritev2(2).
func Pwritev2(t *kernel.Task, sysno uintptr, args arch.SyscallArguments) (uintptr, *kernel.SyscallControl, error) {