Static init of the PS service

ctru-rs/examples/hashmaps.rs

@@ -2,23 +2,19 @@ use ctru::console::Console;
 use ctru::gfx::Gfx;
 use ctru::services::apt::Apt;
 use ctru::services::hid::{Hid, KeyPad};
-use ctru::services::ps::Ps;
 
 fn main() {
     // Initialize services
+    //
+    // HashMaps generate hashes thanks to the 3DS' criptografically secure generator.
+    // This generator is only active when activating the `PS` service.
+    // This service is automatically initialized in `ctru::init`
     ctru::init();
     let apt = Apt::init().unwrap();
     let hid = Hid::init().unwrap();
     let gfx = Gfx::default();
     let _console = Console::init(gfx.top_screen.borrow_mut());
 
-    // HashMaps generate hashes thanks to the 3DS' criptografically secure generator.
-    // Sadly, this generator is only active when activating the `Ps` service.
-    // To do this, we have to make sure the `Ps` service handle is alive for the whole
-    // run time (or at least, when `HashMaps` are used).
-    // Not having a living `Ps` instance when using `HashMap`s results in a panic
-    let _ps = Ps::init().unwrap();
-
     let mut map = std::collections::HashMap::new();
     map.insert("A Key!", 102);
     map.insert("Another key?", 543);

ctru-rs/src/lib.rs

@@ -4,6 +4,12 @@
 #![feature(custom_test_frameworks)]
 #![test_runner(test_runner::run)]
 
+extern "C" fn services_deinit() {
+    unsafe {
+        ctru_sys::psExit();
+    }
+}
+
 /// Call this somewhere to force Rust to link some required crates
 /// This is also a setup for some crate integration only available at runtime
 ///
@@ -12,6 +18,14 @@ pub fn init() {
     linker_fix_3ds::init();
     pthread_3ds::init();
 
+    // Initialize the PS service for random data generation
+    unsafe {
+        ctru_sys::psInit();
+
+        // Setup the deconstruction at the program's end
+        libc::atexit(services_deinit);
+    }
+
     use std::panic::PanicInfo;
 
     let main_thread = thread::current().id();

ctru-rs/src/services/ps.rs

@@ -1,13 +1,9 @@
 //! Process Services (PS) module. This is used for miscellaneous utility tasks, but
 //! is particularly important because it is used to generate random data, which
 //! is required for common things like [`HashMap`](std::collections::HashMap).
+//! As such, it is initialized by default in `ctru::init` instead of having a safety handler
 //! See also <https://www.3dbrew.org/wiki/Process_Services>
 
-/// PS handle. This must not be dropped in order for random generation
-/// to work (in most cases, the lifetime of an application).
-#[non_exhaustive]
-pub struct Ps;
-
 #[repr(u32)]
 pub enum AESAlgorithm {
     CbcEnc,
@@ -32,18 +28,7 @@ pub enum AESKeyType {
     Keyslot39Nfc,
 }
 
-impl Ps {
-    /// Initialize the PS module.
-    pub fn init() -> crate::Result<Self> {
-        let r = unsafe { ctru_sys::psInit() };
-        if r < 0 {
-            Err(r.into())
-        } else {
-            Ok(Self)
-        }
-    }
-
-    pub fn local_friend_code_seed(&self) -> crate::Result<u64> {
+pub fn local_friend_code_seed() -> crate::Result<u64> {
     let mut seed: u64 = 0;
 
     let r = unsafe { ctru_sys::PS_GetLocalFriendCodeSeed(&mut seed) };
@@ -52,9 +37,9 @@ impl Ps {
     } else {
         Ok(seed)
     }
-    }
+}
 
-    pub fn device_id(&self) -> crate::Result<u32> {
+pub fn device_id() -> crate::Result<u32> {
     let mut id: u32 = 0;
 
     let r = unsafe { ctru_sys::PS_GetDeviceId(&mut id) };
@@ -63,25 +48,15 @@ impl Ps {
     } else {
         Ok(id)
     }
-    }
+}
 
-    pub fn generate_random_bytes(&self, out: &mut [u8]) -> crate::Result<()> {
-        let r =
-            unsafe { ctru_sys::PS_GenerateRandomBytes(out as *mut _ as *mut _, out.len() as u32) };
+pub fn generate_random_bytes(out: &mut [u8]) -> crate::Result<()> {
+    let r = unsafe { ctru_sys::PS_GenerateRandomBytes(out as *mut _ as *mut _, out.len() as u32) };
     if r < 0 {
         Err(r.into())
     } else {
         Ok(())
     }
-    }
-}
-
-impl Drop for Ps {
-    fn drop(&mut self) {
-        unsafe {
-            ctru_sys::psExit();
-        }
-    }
 }
 
 #[cfg(test)]
@@ -92,8 +67,6 @@ mod tests {
 
     #[test]
     fn construct_hash_map() {
-        let _ps = Ps::init().unwrap();
-
         let mut input = vec![
             (1_i32, String::from("123")),
             (2, String::from("2")),
@@ -108,34 +81,4 @@ mod tests {
 
         assert_eq!(input, actual);
     }
-
-    #[test]
-    fn construct_hash_map_no_rand() {
-        // Without initializing PS, we can't use `libc::getrandom` and constructing
-        // a HashMap panics at runtime.
-        //
-        // If any test case successfully creates a HashMap before this test,
-        // the thread-local RandomState in std will be initialized. We spawn
-        // a new thread to actually create the hash map, since even in multi-threaded
-        // test environment there's a chance this test wouldn't panic because
-        // some other test case ran before it.
-        //
-        // One downside of this approach is that the panic handler for the panicking
-        // thread prints to the console, which is not captured by the default test
-        // harness and prints even when the test passes.
-        crate::thread::Builder::new()
-            .stack_size(0x20_0000)
-            .spawn(|| {
-                let map: HashMap<i32, String> = HashMap::from_iter([
-                    (1_i32, String::from("123")),
-                    (2, String::from("2")),
-                    (6, String::from("six")),
-                ]);
-
-                dbg!(map);
-            })
-            .unwrap()
-            .join()
-            .expect_err("should have panicked");
-    }
 }