udev_hwdb feature for explicitly enabling hwdb

.github/workflows/build.yml

@@ -14,10 +14,10 @@ jobs:
       fail-fast: false
       matrix:
         job:
-          - { os: ubuntu-latest, target: aarch64-unknown-linux-gnu, use-cross: true }
-          - { os: ubuntu-latest, target: x86_64-pc-windows-gnu, use-cross: true }
-          - { os: ubuntu-latest, target: x86_64-unknown-linux-gnu, use-cross: false }
-          - { os: macos-latest, target: universal-apple-darwin, use-cross: false }
+          - { os: ubuntu-latest, target: aarch64-unknown-linux-gnu, use-cross: true, feature-flags: "-F udev" }
+          - { os: ubuntu-latest, target: x86_64-pc-windows-gnu, use-cross: true, feature-flags: "--all-features"  }
+          - { os: ubuntu-latest, target: x86_64-unknown-linux-gnu, use-cross: false, feature-flags: "--all-features"  }
+          - { os: macos-latest, target: universal-apple-darwin, use-cross: false, feature-flags: "--all-features"  }
     steps:
       - uses: actions/checkout@v4
       - uses: dtolnay/rust-toolchain@v1
@@ -74,14 +74,14 @@ jobs:
         run: |
           case ${{ matrix.job.target }} in
             universal-apple-*) 
-              cargo build --locked --release --all-features --target=aarch64-apple-darwin
-              cargo build --locked --release --all-features --target=x86_64-apple-darwin
+              cargo build --locked --release ${{ matrix.job.feature-flags }} --target=aarch64-apple-darwin
+              cargo build --locked --release ${{ matrix.job.feature-flags }} --target=x86_64-apple-darwin
               mkdir -p target/universal-apple-darwin/release
               # merge into universal
               lipo -create -output target/universal-apple-darwin/release/cyme target/aarch64-apple-darwin/release/cyme target/x86_64-apple-darwin/release/cyme
               ;;
             *) 
-              ${{ env.CARGO_CMD }} build --locked --release --all-features --target=${{ matrix.job.target }}
+              ${{ env.CARGO_CMD }} build --locked --release ${{ matrix.job.feature-flags }} --target=${{ matrix.job.target }}
               ;;
           esac
 

Cargo.toml

@@ -37,20 +37,21 @@ diff = "0.1"
 assert-json-diff = "2.0.2"
 
 [target.x86_64-unknown-linux-gnu.dependencies]
-udev = { version = "^0.8.0", optional = true, features = ["hwdb"] }
+udev = { version = "^0.8.0", optional = true }
 rusb = { git = "https://github.com/tuna-f1sh/rusb.git", version = "0.9.1" }
 
 [target.arm-unknown-linux-gnueabihf.dependencies]
-udev = { version = "^0.8.0", optional = true, features = ["hwdb"] }
+udev = { version = "^0.8.0", optional = true }
 rusb = { git = "https://github.com/tuna-f1sh/rusb.git", version = "0.9.1" }
 
 [target.aarch64-unknown-linux-gnu.dependencies]
-udev = { version = "^0.8.0", optional = true, features = ["hwdb"] }
+udev = { version = "^0.8.0", optional = true }
 rusb = { git = "https://github.com/tuna-f1sh/rusb.git", version = "0.9.1" }
 
 [features]
 libusb = ["dep:rusb"]
 udev = ["dep:udev"]
+udev_hwdb = ["udev/hwdb"]
 usb_test = []
 cli_generate = ["dep:clap_complete", "dep:clap_mangen"] # for generating man and completions
 default = ["libusb"]

src/lib.rs

@@ -45,8 +45,7 @@ pub mod icon;
 pub mod lsusb;
 pub mod system_profiler;
 pub mod types;
-#[cfg(target_os = "linux")]
-#[cfg(feature = "udev")]
+#[cfg(all(target_os = "linux", feature = "udev"))]
 pub mod udev;
 pub mod usb;
 

src/lsusb.rs

@@ -832,13 +832,13 @@ pub mod names {
     /// Wrapper around [`crate::udev::hwdb_get`] so that it can be 'used' without feature
     #[allow(unused_variables)]
     fn hwdb_get(modalias: &str, key: &'static str) -> Result<Option<String>, Error> {
-        #[cfg(all(target_os = "linux", feature = "udev"))]
-        return crate::udev::hwdb_get(modalias, key);
+        #[cfg(all(target_os = "linux", feature = "udev_hwdb"))]
+        return crate::udev::hwdb::hwdb_get(modalias, key);
 
-        #[cfg(not(all(target_os = "linux", feature = "udev")))]
+        #[cfg(not(all(target_os = "linux", feature = "udev_hwdb")))]
         return Err(Error::new(
             ErrorKind::Unsupported,
-            "hwdb_get requires 'udev' feature",
+            "hwdb_get requires 'udev_hwdb' feature",
         ));
     }
 }

src/udev.rs

@@ -129,34 +129,41 @@ pub fn get_udev_attribute<T: AsRef<std::ffi::OsStr> + std::fmt::Display>(
         .map(|s| s.to_str().unwrap_or("").to_string()))
 }
 
-/// Lookup an entry in the udev hwdb given the `modalias` and `key`.
+/// udev hwdb lookup functions
 ///
-/// Should act like https://github.com/gregkh/usbutils/blob/master/names.c#L115
-///
-/// ```
-/// use cyme::udev::hwdb_get;
-///
-/// let modalias = "usb:v1D6Bp0001";
-/// let vendor = hwdb_get(&modalias, "ID_VENDOR_FROM_DATABASE").unwrap();
-///
-/// assert_eq!(vendor, Some("Linux Foundation".into()));
-///
-/// let modalias = "usb:v*p*d*dc03dsc01dp01*";
-/// let vendor = hwdb_get(&modalias, "ID_USB_PROTOCOL_FROM_DATABASE").unwrap();
-///
-/// assert_eq!(vendor, Some("Keyboard".into()));
-/// ```
-pub fn hwdb_get(modalias: &str, key: &'static str) -> Result<Option<String>, Error> {
-    let hwdb = udevlib::Hwdb::new().map_err(|e| {
-        Error::new(
-            ErrorKind::Udev,
-            &format!("Failed to get hwdb: Error({})", e.to_string()),
-        )
-    })?;
+/// Protected by the `udev_hwdb` feature because 'libudev-sys' excludes hwdb ffi bindings if native udev does not support hwdb
+#[cfg(feature = "udev_hwdb")]
+pub mod hwdb {
+    use super::*;
+    /// Lookup an entry in the udev hwdb given the `modalias` and `key`.
+    ///
+    /// Should act like https://github.com/gregkh/usbutils/blob/master/names.c#L115
+    ///
+    /// ```
+    /// use cyme::udev::hwdb_get;
+    ///
+    /// let modalias = "usb:v1D6Bp0001";
+    /// let vendor = hwdb_get(&modalias, "ID_VENDOR_FROM_DATABASE").unwrap();
+    ///
+    /// assert_eq!(vendor, Some("Linux Foundation".into()));
+    ///
+    /// let modalias = "usb:v*p*d*dc03dsc01dp01*";
+    /// let vendor = hwdb_get(&modalias, "ID_USB_PROTOCOL_FROM_DATABASE").unwrap();
+    ///
+    /// assert_eq!(vendor, Some("Keyboard".into()));
+    /// ```
+    pub fn hwdb_get(modalias: &str, key: &'static str) -> Result<Option<String>, Error> {
+        let hwdb = udevlib::Hwdb::new().map_err(|e| {
+            Error::new(
+                ErrorKind::Udev,
+                &format!("Failed to get hwdb: Error({})", e.to_string()),
+            )
+        })?;
 
-    Ok(hwdb
-        .query_one(&modalias.to_string(), &key.to_string())
-        .map(|s| s.to_str().unwrap_or("").to_string()))
+        Ok(hwdb
+            .query_one(&modalias.to_string(), &key.to_string())
+            .map(|s| s.to_str().unwrap_or("").to_string()))
+    }
 }
 
 #[cfg(test)]
@@ -173,7 +180,7 @@ mod tests {
     }
 
     /// Tests can lookup bInterfaceClass of the root hub, which is always 09
-    #[cfg_attr(not(feature = "usb_test"), ignore)]
+    #[cfg_attr(not(feature = "usb_test", feature = "udev_hwdb"), ignore)]
     #[test]
     fn test_udev_attribute() {
         let interface_class = get_udev_attribute("1-0:1.0", "bInterfaceClass").unwrap();