Fix android build

src/api/android/mod.rs

@@ -257,7 +257,7 @@ impl HeadlessContext {
     pub fn new(builder: BuilderAttribs) -> Result<HeadlessContext, CreationError> {
         let context = try!(EglContext::new(egl::ffi::egl::Egl, &builder, egl::NativeDisplay::Android));
         let context = try!(context.finish_pbuffer());
-        Ok(context)
+        Ok(HeadlessContext(context))
     }
 }
 

src/api/egl/mod.rs

@@ -41,20 +41,15 @@ pub struct Context {
     pixel_format: PixelFormat,
 }
 
-impl Context {
-    /// Start building an EGL context.
-    ///
-    /// This function initializes some things and chooses the pixel format.
-    ///
-    /// To finish the process, you must call `.finish(window)` on the `ContextPrototype`.
-    pub fn new<'a>(egl: ffi::egl::Egl, builder: &'a BuilderAttribs<'a>,
-                   native_display: NativeDisplay)
-                   -> Result<ContextPrototype<'a>, CreationError>
-    {
-        if builder.sharing.is_some() {
-            unimplemented!()
+#[cfg(target_os = "android")]
+fn get_native_display(egl: &ffi::egl::Egl,
+                      native_display: NativeDisplay) -> *const libc::c_void {
+    unsafe { egl.GetDisplay(ffi::egl::DEFAULT_DISPLAY as *mut _) }
 }
 
+#[cfg(not(target_os = "android"))]
+fn get_native_display(egl: &ffi::egl::Egl,
+                      native_display: NativeDisplay) -> *const libc::c_void {
     // the first step is to query the list of extensions without any display, if supported
     let dp_extensions = unsafe {
         let p = egl.QueryString(ffi::egl::NO_DISPLAY, ffi::egl::EXTENSIONS as i32);
@@ -72,8 +67,7 @@ impl Context {
 
     let has_dp_extension = |e: &str| dp_extensions.iter().find(|s| s == &e).is_some();
 
-        // calling `eglGetDisplay` or equivalent
-        let display = match native_display {
+    match native_display {
         // Note: Some EGL implementations are missing the `eglGetPlatformDisplay(EXT)` symbol
         //       despite reporting `EGL_EXT_platform_base`. I'm pretty sure this is a bug.
         //       Therefore we detect whether the symbol is loaded in addition to checking for
@@ -128,6 +122,8 @@ impl Context {
                                                ptr::null()) }
         },
 
+        // TODO: This will never be reached right now, as the android egl bindings
+        // use the static generator, so can't rely on GetPlatformDisplay(EXT).
         NativeDisplay::Android if has_dp_extension("EGL_KHR_platform_android") &&
                                   egl.GetPlatformDisplay.is_loaded() =>
         {
@@ -152,7 +148,25 @@ impl Context {
         NativeDisplay::Android | NativeDisplay::Other(None) => {
             unsafe { egl.GetDisplay(ffi::egl::DEFAULT_DISPLAY as *mut _) }
         },
-        };
+    }
+}
+
+impl Context {
+    /// Start building an EGL context.
+    ///
+    /// This function initializes some things and chooses the pixel format.
+    ///
+    /// To finish the process, you must call `.finish(window)` on the `ContextPrototype`.
+    pub fn new<'a>(egl: ffi::egl::Egl, builder: &'a BuilderAttribs<'a>,
+                   native_display: NativeDisplay)
+                   -> Result<ContextPrototype<'a>, CreationError>
+    {
+        if builder.sharing.is_some() {
+            unimplemented!()
+        }
+
+        // calling `eglGetDisplay` or equivalent
+        let display = get_native_display(&egl, native_display);
 
         if display.is_null() {
             return Err(CreationError::OsError("Could not create EGL display object".to_string()));