HID report descriptor item parser
Example
Using items directly
const QEMU_USB_TABLET: &[u8] = &[
0x05, 0x01, 0x09, 0x02, 0xa1, 0x01, 0x09, 0x01, 0xa1, 0x00, 0x05, 0x09, 0x19, 0x01, 0x29,
0x03, 0x15, 0x00, 0x25, 0x01, 0x95, 0x03, 0x75, 0x01, 0x81, 0x02, 0x95, 0x01, 0x75, 0x05,
0x81, 0x01, 0x05, 0x01, 0x09, 0x30, 0x09, 0x31, 0x15, 0x00, 0x26, 0xff, 0x7f, 0x35, 0x00,
0x46, 0xff, 0x7f, 0x75, 0x10, 0x95, 0x02, 0x81, 0x02, 0x05, 0x01, 0x09, 0x38, 0x15, 0x81,
0x25, 0x7f, 0x35, 0x00, 0x45, 0x00, 0x75, 0x08, 0x95, 0x01, 0x81, 0x06, 0xc0, 0xc0,
];
dbg!(usb_hid_item::parse(QEMU_USB_TABLET).collect::<Vec<_>>());
Using the tree parser
const QEMU_USB_TABLET: &[u8] = &[
0x05, 0x01, 0x09, 0x02, 0xa1, 0x01, 0x09, 0x01, 0xa1, 0x00, 0x05, 0x09, 0x19, 0x01, 0x29,
0x03, 0x15, 0x00, 0x25, 0x01, 0x95, 0x03, 0x75, 0x01, 0x81, 0x02, 0x95, 0x01, 0x75, 0x05,
0x81, 0x01, 0x05, 0x01, 0x09, 0x30, 0x09, 0x31, 0x15, 0x00, 0x26, 0xff, 0x7f, 0x35, 0x00,
0x46, 0xff, 0x7f, 0x75, 0x10, 0x95, 0x02, 0x81, 0x02, 0x05, 0x01, 0x09, 0x38, 0x15, 0x81,
0x25, 0x7f, 0x35, 0x00, 0x45, 0x00, 0x75, 0x08, 0x95, 0x01, 0x81, 0x06, 0xc0, 0xc0,
];
use {
usb_hid_item::tree::{Value, Field},
core::{mem, ops::RangeInclusive},
};
type Usages = Vec<(u16, RangeInclusive<u16>)>;
let mut report = Vec::new();
let mut usages = Usages::new();
fn f(val: Value, fields: &mut Vec<(Usages, Field)>, usages: &mut Usages) {
match val {
Value::Collection(c) => {
usages.clear();
c.for_each(|c| f(val.unwrap(), fields, usages));
}
Value::Usage { page, ids } => usages.push((page, ids)),
Value::Field(f) => fields.push((mem::take(usages), f)),
}
}
usb_hid_item::tree::parse(data)
.iter()
.for_each(|c| f(c.unwrap(), &mut fields, &mut usages));
dbg!(fields);
References
