feat: add safe bindings to abort callback

src/whisper_params.rs

@@ -27,6 +27,7 @@ pub struct FullParams<'a, 'b> {
     phantom_tokens: PhantomData<&'b [c_int]>,
     grammar: Option<Vec<whisper_rs_sys::whisper_grammar_element>>,
     progess_callback_safe: Option<Box<dyn FnMut(i32)>>,
+    abort_callback_safe: Option<Box<dyn FnMut() -> bool>>,
 }
 
 impl<'a, 'b> FullParams<'a, 'b> {
@@ -62,6 +63,7 @@ impl<'a, 'b> FullParams<'a, 'b> {
             phantom_tokens: PhantomData,
             grammar: None,
             progess_callback_safe: None,
+            abort_callback_safe: None,
         }
     }
 
@@ -450,6 +452,51 @@ impl<'a, 'b> FullParams<'a, 'b> {
         }
     }
 
+    /// Set the callback for abort conditions, potentially using a closure.
+    ///
+    /// Note that, for safety, the callback only accepts a function that returns a boolean
+    /// indicating whether to abort or not.
+    ///
+    /// See `set_progress_callback` if you need to use `whisper_context` and `whisper_state`,
+    /// or extend this one to support their use.
+    ///
+    /// Defaults to None.
+    pub fn set_abort_callback_safe<O, F>(&mut self, closure: O)
+    where
+        F: FnMut() -> bool + 'static,
+        O: Into<Option<F>>,
+    {
+        use std::ffi::c_void;
+
+        unsafe extern "C" fn trampoline<F>(user_data: *mut c_void) -> bool
+        where
+            F: FnMut() -> bool,
+        {
+            let user_data = &mut *(user_data as *mut F);
+            user_data()
+        }
+
+        match closure.into() {
+            Some(closure) => {
+                // Stable address
+                let closure = Box::new(closure) as Box<dyn FnMut() -> bool>;
+                // Thin pointer
+                let closure = Box::new(closure);
+                // Raw pointer
+                let closure = Box::into_raw(closure);
+
+                self.fp.abort_callback = Some(trampoline::<F>);
+                self.fp.abort_callback_user_data = closure as *mut c_void;
+                self.abort_callback_safe = None;
+            }
+            None => {
+                self.fp.abort_callback = None;
+                self.fp.abort_callback_user_data = std::ptr::null_mut::<c_void>();
+                self.abort_callback_safe = None;
+            }
+        }
+    }
+
     /// Set the user data to be passed to the progress callback.
     ///
     /// # Safety