OHOS: Use native API to get most of the information needed for starting servoshell. (#37392)

Uses the native ohos-api crates to get the required information for
starting servoshell.
This increases the minimum API version requirement to API-14.

Testing: Tested on device.

---------

Signed-off-by: Narfinger <Narfinger@users.noreply.github.com>
Co-authored-by: Jonathan Schwender <55576758+jschwe@users.noreply.github.com>

ports/servoshell/egl/ohos/simpleservo.rs

@@ -2,6 +2,7 @@
  * License, v. 2.0. If a copy of the MPL was not distributed with this
  * file, You can obtain one at https://mozilla.org/MPL/2.0/. */
 use std::cell::RefCell;
+use std::ffi::{CString, c_char};
 use std::fs;
 use std::os::raw::c_void;
 use std::path::PathBuf;
@@ -9,7 +10,9 @@ use std::ptr::NonNull;
 use std::rc::Rc;
 
 use dpi::PhysicalSize;
-use log::{debug, info, warn};
+use log::{debug, error, info, warn};
+use ohos_abilitykit_sys::runtime::application_context;
+use ohos_window_manager_sys::display_manager;
 use raw_window_handle::{
     DisplayHandle, OhosDisplayHandle, OhosNdkWindowHandle, RawDisplayHandle, RawWindowHandle,
     WindowHandle,
@@ -23,6 +26,46 @@ use crate::egl::ohos::InitOpts;
 use crate::egl::ohos::resources::ResourceReaderInstance;
 use crate::prefs::{ArgumentParsingResult, parse_command_line_arguments};
 
+#[derive(Debug)]
+struct NativeValues {
+    cache_dir: String,
+    display_density: f32,
+    device_type: ohos_deviceinfo::OhosDeviceType,
+    os_full_name: String,
+}
+
+/// Gets the resource and cache directory from the native c methods.
+fn get_native_values() -> NativeValues {
+    let cache_dir = {
+        const BUFFER_SIZE: i32 = 100;
+        let mut buffer: Vec<u8> = Vec::with_capacity(BUFFER_SIZE as usize);
+        let mut write_length = 0;
+        unsafe {
+            application_context::OH_AbilityRuntime_ApplicationContextGetCacheDir(
+                buffer.as_mut_ptr().cast(),
+                BUFFER_SIZE,
+                &mut write_length,
+            )
+            .expect("Call to cache dir failed");
+            buffer.set_len(write_length as usize);
+            String::from_utf8(buffer).expect("UTF-8")
+        }
+    };
+    let display_density = unsafe {
+        let mut density: f32 = 0_f32;
+        display_manager::OH_NativeDisplayManager_GetDefaultDisplayDensityPixels(&mut density)
+            .expect("Could not get displaydensity");
+        density
+    };
+
+    NativeValues {
+        cache_dir,
+        display_density,
+        device_type: ohos_deviceinfo::get_device_type(),
+        os_full_name: String::from(ohos_deviceinfo::get_os_full_name().unwrap_or("Undefined")),
+    }
+}
+
 /// Initialize Servo. At that point, we need a valid GL context.
 /// In the future, this will be done in multiple steps.
 pub fn init(
@@ -34,6 +77,12 @@ pub fn init(
 ) -> Result<Rc<RunningAppState>, &'static str> {
     info!("Entered simpleservo init function");
     crate::init_crypto();
+
+    let native_values = get_native_values();
+    info!("Device Type {:?}", native_values.device_type);
+    info!("OS Full Name {:?}", native_values.os_full_name);
+    info!("ResourceDir {:?}", options.resource_dir);
+
     let resource_dir = PathBuf::from(&options.resource_dir).join("servo");
     debug!("Resources are located at: {:?}", resource_dir);
     resources::set(Box::new(ResourceReaderInstance::new(resource_dir.clone())));
@@ -49,7 +98,7 @@ pub fn init(
     );
     debug!("Servo commandline args: {:?}", args);
 
-    let config_dir = PathBuf::from(&options.cache_dir).join("servo");
+    let config_dir = PathBuf::from(&native_values.cache_dir).join("servo");
     debug!("Configs are located at: {:?}", config_dir);
     let _ = crate::prefs::DEFAULT_CONFIG_DIR
         .set(config_dir.clone())
@@ -133,7 +182,7 @@ pub fn init(
 
     let app_state = RunningAppState::new(
         Some(options.url),
-        options.display_density as f32,
+        native_values.display_density as f32,
         rendering_context,
         servo,
         window_callbacks,