use libc::c_int;
use std::{mem, slice};
use crate::{
context::{GlobalContext, UsbContext},
device::{self, Device},
error,
};
use libusb1_sys::*;
pub struct DeviceList<T: UsbContext> {
context: T,
list: *const *mut libusb_device,
len: usize,
}
impl<T: UsbContext> Drop for DeviceList<T> {
fn drop(&mut self) {
unsafe {
libusb_free_device_list(self.list, 1);
}
}
}
impl DeviceList<GlobalContext> {
pub fn new() -> crate::Result<DeviceList<GlobalContext>> {
let mut list = mem::MaybeUninit::<*const *mut libusb_device>::uninit();
let n =
unsafe { libusb_get_device_list(GlobalContext::default().as_raw(), list.as_mut_ptr()) };
if n < 0 {
Err(error::from_libusb(n as c_int))
} else {
Ok(unsafe {
DeviceList {
context: Default::default(),
list: list.assume_init(),
len: n as usize,
}
})
}
}
}
impl<T: UsbContext> DeviceList<T> {
pub fn new_with_context(context: T) -> crate::Result<DeviceList<T>> {
let mut list = mem::MaybeUninit::<*const *mut libusb_device>::uninit();
let len = unsafe { libusb_get_device_list(context.as_raw(), list.as_mut_ptr()) };
if len < 0 {
Err(error::from_libusb(len as c_int))
} else {
Ok(unsafe {
DeviceList {
context,
list: list.assume_init(),
len: len as usize,
}
})
}
}
pub fn len(&self) -> usize {
self.len
}
pub fn is_empty(&self) -> bool {
self.len == 0
}
pub fn iter(&self) -> Devices<T> {
Devices {
context: self.context.clone(),
devices: unsafe { slice::from_raw_parts(self.list, self.len) },
index: 0,
}
}
}
pub struct Devices<'a, T> {
context: T,
devices: &'a [*mut libusb_device],
index: usize,
}
impl<'a, T: UsbContext> Iterator for Devices<'a, T> {
type Item = Device<T>;
fn next(&mut self) -> Option<Device<T>> {
if self.index < self.devices.len() {
let device = self.devices[self.index];
self.index += 1;
Some(unsafe {
device::Device::from_libusb(
self.context.clone(),
std::ptr::NonNull::new_unchecked(device),
)
})
} else {
None
}
}
fn size_hint(&self) -> (usize, Option<usize>) {
let remaining = self.devices.len() - self.index;
(remaining, Some(remaining))
}
}