Merge pull request #138 from sidit77/master

Simplified conditional compilation

Cargo.toml

@@ -42,6 +42,7 @@ windows-native = [
 
 [dependencies]
 libc = "0.2"
+cfg-if = "1"
 
 [target.'cfg(target_os = "linux")'.dependencies]
 udev = { version = "0.7", optional = true }

src/lib.rs

@@ -58,36 +58,10 @@
 //! [`HidDevice`] handles can access the same physical device. For backward compatibility this is
 //! an opt-in that can be enabled with the `macos-shared-device` feature flag.
 
-extern crate libc;
-#[cfg(all(feature = "linux-native", target_os = "linux"))]
-extern crate nix;
-
-#[cfg(target_os = "windows")]
-use windows_sys::core::GUID;
-
 mod error;
 mod ffi;
 
-#[cfg(hidapi)]
-mod hidapi;
-
-#[cfg(all(feature = "linux-native", target_os = "linux"))]
-#[cfg_attr(docsrs, doc(cfg(all(feature = "linux-native", target_os = "linux"))))]
-mod linux_native;
-#[cfg(target_os = "macos")]
-#[cfg_attr(docsrs, doc(cfg(target_os = "macos")))]
-mod macos;
-#[cfg(target_os = "windows")]
-#[cfg_attr(docsrs, doc(cfg(target_os = "windows")))]
-mod windows;
-
-#[cfg(feature = "windows-native")]
-#[cfg_attr(
-    docsrs,
-    doc(cfg(all(feature = "windows-native", target_os = "windows")))
-)]
-mod windows_native;
-
+use cfg_if::cfg_if;
 use libc::wchar_t;
 use std::ffi::CStr;
 use std::ffi::CString;
@@ -97,12 +71,54 @@ use std::sync::Mutex;
 
 pub use error::HidError;
 
-#[cfg(hidapi)]
-use crate::hidapi::HidApiBackend;
-#[cfg(all(feature = "linux-native", target_os = "linux"))]
-use linux_native::HidApiBackend;
-#[cfg(all(feature = "windows-native", target_os = "windows"))]
-use windows_native::HidApiBackend;
+cfg_if! {
+    if #[cfg(all(feature = "linux-native", target_os = "linux"))] {
+        //#[cfg_attr(docsrs, doc(cfg(all(feature = "linux-native", target_os = "linux"))))]
+        mod linux_native;
+        use linux_native::HidApiBackend;
+    } else if #[cfg(all(feature = "windows-native", target_os = "windows"))] {
+        //#[cfg_attr(docsrs, doc(cfg(all(feature = "windows-native", target_os = "windows"))))]
+        mod windows_native;
+        use windows_native::HidApiBackend;
+    } else if #[cfg(hidapi)] {
+        mod hidapi;
+        use hidapi::HidApiBackend;
+    } else {
+        compile_error!("No backend selected");
+    }
+}
+
+// Automatically implement the top trait
+cfg_if! {
+    if #[cfg(target_os = "windows")] {
+        #[cfg_attr(docsrs, doc(cfg(target_os = "windows")))]
+        mod windows;
+        use windows::GUID;
+        /// A trait with the extra methods that are available on Windows
+        trait HidDeviceBackendWindows {
+            /// Get the container ID for a HID device
+            fn get_container_id(&self) -> HidResult<GUID>;
+        }
+        trait HidDeviceBackend: HidDeviceBackendBase + HidDeviceBackendWindows + Send {}
+        impl<T> HidDeviceBackend for T where T: HidDeviceBackendBase + HidDeviceBackendWindows + Send {}
+    } else if #[cfg(target_os = "macos")] {
+        #[cfg_attr(docsrs, doc(cfg(target_os = "macos")))]
+        mod macos;
+        /// A trait with the extra methods that are available on macOS
+        trait HidDeviceBackendMacos {
+            /// Get the location ID for a [`HidDevice`] device.
+            fn get_location_id(&self) -> HidResult<u32>;
+
+            /// Check if the device was opened in exclusive mode.
+            fn is_open_exclusive(&self) -> HidResult<bool>;
+        }
+        trait HidDeviceBackend: HidDeviceBackendBase + HidDeviceBackendMacos + Send {}
+        impl<T> HidDeviceBackend for T where T: HidDeviceBackendBase + HidDeviceBackendMacos + Send {}
+    } else {
+        trait HidDeviceBackend: HidDeviceBackendBase + Send {}
+        impl<T> HidDeviceBackend for T where T: HidDeviceBackendBase + Send {}
+    }
+}
 
 pub type HidResult<T> = Result<T, HidError>;
 pub const MAX_REPORT_DESCRIPTOR_SIZE: usize = 4096;
@@ -471,42 +487,6 @@ trait HidDeviceBackendBase {
     }
 }
 
-/// A trait with the extra methods that are available on macOS
-#[cfg(target_os = "macos")]
-trait HidDeviceBackendMacos {
-    /// Get the location ID for a [`HidDevice`] device.
-    fn get_location_id(&self) -> HidResult<u32>;
-
-    /// Check if the device was opened in exclusive mode.
-    fn is_open_exclusive(&self) -> HidResult<bool>;
-}
-
-/// A trait with the extra methods that are available on macOS
-#[cfg(target_os = "windows")]
-trait HidDeviceBackendWindows {
-    /// Get the container ID for a HID device
-    fn get_container_id(&self) -> HidResult<GUID>;
-}
-
-#[cfg(not(any(target_os = "macos", target_os = "windows")))]
-trait HidDeviceBackend: HidDeviceBackendBase + Send {}
-#[cfg(target_os = "macos")]
-trait HidDeviceBackend: HidDeviceBackendBase + HidDeviceBackendMacos + Send {}
-#[cfg(target_os = "windows")]
-trait HidDeviceBackend: HidDeviceBackendBase + HidDeviceBackendWindows + Send {}
-
-/// Automatically implement the top trait
-#[cfg(not(any(target_os = "macos", target_os = "windows")))]
-impl<T> HidDeviceBackend for T where T: HidDeviceBackendBase + Send {}
-
-/// Automatically implement the top trait
-#[cfg(target_os = "macos")]
-impl<T> HidDeviceBackend for T where T: HidDeviceBackendBase + HidDeviceBackendMacos + Send {}
-
-/// Automatically implement the top trait
-#[cfg(target_os = "windows")]
-impl<T> HidDeviceBackend for T where T: HidDeviceBackendBase + HidDeviceBackendWindows + Send {}
-
 pub struct HidDevice {
     inner: Box<dyn HidDeviceBackend>,
 }

src/windows.rs

@@ -1,5 +1,5 @@
 use crate::{HidDevice, HidResult};
-use windows_sys::core::GUID;
+pub use windows_sys::core::GUID;
 
 impl HidDevice {
     /// Get the container ID for a HID device.

src/windows_native/descriptor/mod.rs

@@ -4,7 +4,6 @@ mod tests;
 mod typedefs;
 mod types;
 
-use crate::ensure;
 use crate::windows_native::descriptor::encoder::encode_descriptor;
 use crate::windows_native::descriptor::typedefs::{Caps, HidpPreparsedData, LinkCollectionNode};
 use crate::windows_native::descriptor::types::{

src/windows_native/dev_node.rs

@@ -1,4 +1,3 @@
-use crate::ensure;
 use crate::windows_native::error::{check_config, WinError, WinResult};
 use crate::windows_native::string::U16Str;
 use crate::windows_native::types::{DeviceProperty, PropertyKey};

src/windows_native/hid.rs

@@ -1,4 +1,3 @@
-use crate::ensure;
 use crate::windows_native::error::{check_boolean, WinError, WinResult};
 use crate::windows_native::types::Handle;
 use std::ffi::c_void;

src/windows_native/interfaces.rs

@@ -1,4 +1,3 @@
-use crate::ensure;
 use crate::windows_native::error::{check_config, WinError, WinResult};
 use crate::windows_native::hid::get_interface_guid;
 use crate::windows_native::string::{U16Str, U16StringList};

src/windows_native/mod.rs

@@ -1,4 +1,12 @@
-//! The implementation which uses the C library to perform operations
+//! The implementation which uses the the raw win32 api to perform operations
+
+macro_rules! ensure {
+    ($cond:expr, $result:expr) => {
+        if !($cond) {
+            return $result;
+        }
+    };
+}
 
 mod descriptor;
 mod dev_node;
@@ -42,15 +50,6 @@ use windows_sys::Win32::System::IO::{CancelIo, DeviceIoControl};
 
 const STRING_BUF_LEN: usize = 128;
 
-#[macro_export]
-macro_rules! ensure {
-    ($cond:expr, $result:expr) => {
-        if !($cond) {
-            return $result;
-        }
-    };
-}
-
 pub struct HidApiBackend;
 impl HidApiBackend {
     pub fn get_hid_device_info_vector(vid: u16, pid: u16) -> HidResult<Vec<DeviceInfo>> {

src/windows_native/types.rs

@@ -1,5 +1,5 @@
 use crate::windows_native::error::{WinError, WinResult};
-use crate::{ensure, BusType};
+use crate::BusType;
 use std::mem::{size_of, zeroed};
 use std::ptr::null;
 use windows_sys::core::GUID;