Expose device path types (#202)

src/proto/device_path.rs

@@ -0,0 +1,84 @@
+//! `DevicePath` protocol
+
+use crate::{proto::Protocol, unsafe_guid};
+
+/// Device path protocol.
+///
+/// This can be opened on a `LoadedImage.device()` handle using the `HandleProtocol` boot service.
+#[repr(C)]
+#[unsafe_guid("09576e91-6d3f-11d2-8e39-00a0c969723b")]
+#[derive(Protocol)]
+pub struct DevicePath {
+    /// Type of device
+    pub device_type: DeviceType,
+    /// Sub type of device
+    pub sub_type: DeviceSubType,
+    /// Data related to device path
+    ///
+    /// The `device_type` and `sub_type` determine the kind of data, and its size.
+    pub length: [u8; 2],
+}
+
+/// Type identifier for a DevicePath
+#[repr(u8)]
+#[derive(Debug, PartialEq)]
+pub enum DeviceType {
+    /// Hardware Device Path.
+    ///
+    /// This Device Path defines how a device is attached to the resource domain of a system, where resource domain is
+    /// simply the shared memory, memory mapped I/ O, and I/O space of the system.
+    Hardware = 0x01,
+    /// ACPI Device Path.
+    ///
+    /// This Device Path is used to describe devices whose enumeration is not described in an industry-standard fashion.
+    /// These devices must be described using ACPI AML in the ACPI namespace; this Device Path is a linkage to the ACPI
+    /// namespace.
+    Acpi = 0x02,
+    /// Messaging Device Path.
+    ///
+    /// This Device Path is used to describe the connection of devices outside the resource domain of the system. This
+    /// Device Path can describe physical messaging information such as a SCSI ID, or abstract information such as
+    /// networking protocol IP addresses.
+    Messaging = 0x03,
+    /// Media Device Path.
+    ///
+    /// This Device Path is used to describe the portion of a medium that is being abstracted by a boot service.
+    /// For example, a Media Device Path could define which partition on a hard drive was being used.
+    Media = 0x04,
+    /// BIOS Boot Specification Device Path.
+    ///
+    /// This Device Path is used to point to boot legacy operating systems; it is based on the BIOS Boot Specification
+    /// Version 1.01.
+    BiosBootSpec = 0x05,
+    /// End of Hardware Device Path.
+    ///
+    /// Depending on the Sub-Type, this Device Path node is used to indicate the end of the Device Path instance or
+    /// Device Path structure.
+    End = 0x7F,
+}
+
+/// Sub-type identifier for a DevicePath
+#[repr(u8)]
+#[derive(Debug)]
+pub enum DeviceSubType {
+    /// End This Instance of a Device Path and start a new Device Path
+    EndInstance = 0x01,
+    /// End Entire Device Path
+    EndEntire = 0xFF,
+}
+
+/// ACPI Device Path
+#[repr(C)]
+pub struct AcpiDevicePath {
+    /// Type of device, which is ACPI Device Path
+    pub device_type: DeviceType,
+    /// Sub type of the device, which is ACPI Device Path
+    pub sub_type: DeviceSubType,
+    /// Device's PnP hardware ID stored in a numeric 32-bit compressed EISA-type ID. This value must match the
+    /// corresponding _HID in the ACPI name space.
+    pub hid: u32,
+    /// Unique ID that is required by ACPI if two devices have the same _HID. This value must also match the
+    /// corresponding _UID/_HID pair in the ACPI name space. Only the 32-bit numeric value type of _UID is supported;
+    /// thus strings must not be used for the _UID in the ACPI name space.
+    pub uid: u32,
+}

src/proto/loaded_image/mod.rs → src/proto/loaded_image.rs

@@ -1,10 +1,4 @@
 //! `LoadedImage` protocol.
-//!
-//! This module also contains the corollary type `DevicePath`, which is
-//! used to wrap an `EFI_DEVICE_PATH_PROTOCOL`.
-
-mod device_path;
-pub use self::device_path::DevicePath;
 
 use crate::{
     data_types::{CStr16, Char16},

src/proto/mod.rs

@@ -28,6 +28,7 @@ pub use uefi_macros::Protocol;
 
 pub mod console;
 pub mod debug;
+pub mod device_path;
 pub mod loaded_image;
 pub mod media;
 pub mod pi;

src/table/boot.rs

@@ -1,10 +1,7 @@
 //! UEFI services available during boot.
 
 use super::Header;
-use crate::proto::{
-    loaded_image::{DevicePath, LoadedImage},
-    Protocol,
-};
+use crate::proto::{device_path::DevicePath, loaded_image::LoadedImage, Protocol};
 use crate::{data_types::Align, proto::media::fs::SimpleFileSystem};
 use crate::{Event, Guid, Handle, Result, Status};
 #[cfg(feature = "exts")]