From 4adcffe2cec22fda1d753d5fb3b95cb6eb511eb2 Mon Sep 17 00:00:00 2001
From: Marijn Suijten <marijns95@gmail.com>
Date: Sat, 10 Aug 2024 15:25:09 +0200
Subject: [PATCH] Add bindings for Permission Manager (`checkPermission()`)

---
 ndk/CHANGELOG.md              |  1 +
 ndk/src/lib.rs                |  1 +
 ndk/src/permission_manager.rs | 53 +++++++++++++++++++++++++++++++++++
 3 files changed, 55 insertions(+)
 create mode 100644 ndk/src/permission_manager.rs

diff --git a/ndk/CHANGELOG.md b/ndk/CHANGELOG.md
index 4bc9a7e2..ec7c4e61 100644
--- a/ndk/CHANGELOG.md
+++ b/ndk/CHANGELOG.md
@@ -1,6 +1,7 @@
 # Unreleased
 
 - image_reader: Add `ImageReader::new_with_data_space()` constructor and `ImageReader::data_space()` getter from API level 34. (#474)
+- Add bindings for Permission Manager (`checkPermission()`). (#484)
 
 # 0.9.0 (2024-04-26)
 
diff --git a/ndk/src/lib.rs b/ndk/src/lib.rs
index 81e2ef61..a628e0a3 100644
--- a/ndk/src/lib.rs
+++ b/ndk/src/lib.rs
@@ -26,6 +26,7 @@ pub mod media;
 pub mod media_error;
 pub mod native_activity;
 pub mod native_window;
+pub mod permission_manager;
 pub mod shared_memory;
 pub mod surface_texture;
 pub mod sync;
diff --git a/ndk/src/permission_manager.rs b/ndk/src/permission_manager.rs
new file mode 100644
index 00000000..53378e51
--- /dev/null
+++ b/ndk/src/permission_manager.rs
@@ -0,0 +1,53 @@
+//! Bindings for permission checks
+//!
+//! <https://developer.android.com/ndk/reference/group/permission>
+#![cfg(feature = "api-level-31")]
+
+use std::{ffi::CStr, mem::MaybeUninit};
+
+use num_enum::{FromPrimitive, IntoPrimitive};
+
+/// Permission check return status values.
+#[repr(i32)]
+#[derive(Copy, Clone, Debug, PartialEq, Eq, FromPrimitive, IntoPrimitive)]
+#[non_exhaustive]
+pub enum PermissionManagerStatus {
+    /// This is returned if the permission check encountered an unspecified error.
+    ErrorUnknown = ffi::PERMISSION_MANAGER_STATUS_ERROR_UNKNOWN,
+    /// This is returned if the permission check failed because the service is unavailable.
+    ServiceUnavailable = ffi::PERMISSION_MANAGER_STATUS_SERVICE_UNAVAILABLE,
+
+    #[doc(hidden)]
+    #[num_enum(catch_all)]
+    __Unknown(i32) = 0,
+}
+
+/// Checks whether the package with the given pid/uid has been granted a permission.
+///
+/// Note that the Java API of [`Context#checkPermission()`] is usually faster due to caching,
+/// thus is preferred over this API wherever possible.
+///
+/// [`Context#checkPermission()`]: https://developer.android.com/reference/android/content/Context#checkPermission(java.lang.String,%20int,%20int)
+///
+/// # Parameters
+/// - `permission`: the permission to be checked.
+/// - `pid`: the process id of the package to be checked.
+/// - `uid`: the uid of the package to be checked.
+#[doc(alias = "APermissionManager_checkPermission")]
+pub fn check_permission(
+    permission: &CStr,
+    pid: i32,
+    uid: u32,
+) -> Result<bool, PermissionManagerStatus> {
+    let mut result = MaybeUninit::uninit();
+    match unsafe {
+        ffi::APermissionManager_checkPermission(permission.as_ptr(), pid, uid, result.as_mut_ptr())
+    } {
+        ffi::PERMISSION_MANAGER_STATUS_OK => Ok(match unsafe { result.assume_init() } {
+            ffi::PERMISSION_MANAGER_PERMISSION_GRANTED => true,
+            ffi::PERMISSION_MANAGER_PERMISSION_DENIED => false,
+            x => unreachable!("Unexpected `PERMISSION` result output {x}"),
+        }),
+        x => Err(x.into()),
+    }
+}