Remove some uses of static mut

declantsien · Apr 13, 2024 · df8b8fc · df8b8fc
1 parent 2b770d9
commit df8b8fc
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Showing 6 changed files with 74 additions and 41 deletions.
diff --git a/crates/emacs-sys/src/lisp.rs b/crates/emacs-sys/src/lisp.rs
@@ -205,6 +205,7 @@ impl LispObject {
 pub struct ExternalPtr<T>(*mut T);
 
 impl<T> Copy for ExternalPtr<T> {}
+unsafe impl<T> Send for ExternalPtr<T> {}
 
 // Derive fails for this type so do it manually
 impl<T> Clone for ExternalPtr<T> {

diff --git a/crates/winit/src/fns.rs b/crates/winit/src/fns.rs
@@ -16,6 +16,7 @@ use font::register_swash_font_driver;
 use raw_window_handle::RawWindowHandle;
 use std::ffi::CString;
 use std::ptr;
+use std::sync::Mutex;
 use webrender_api::*;
 use winit::dpi::LogicalSize;
 
@@ -75,7 +76,33 @@ pub type DisplayRef = ExternalPtr<Display>;
 pub static tip_frame: LispObject = Qnil;
 
 #[no_mangle]
-pub static mut winit_display_list: DisplayInfoRef = DisplayInfoRef::new(ptr::null_mut());
+pub static WINIT_DISPLAY_LIST: Mutex<DisplayInfoRef> =
+    Mutex::new(DisplayInfoRef::new(ptr::null_mut()));
+
+fn winit_display_list() -> DisplayInfoRef {
+    let v = WINIT_DISPLAY_LIST.lock().map_or_else(
+        |e| {
+            log::error!("failed to read winit_display_list: {e:?}");
+            DisplayInfoRef::new(ptr::null_mut())
+        },
+        |v| v.clone(),
+    );
+    v
+}
+
+fn set_winit_display_list(dpyinfo: DisplayInfoRef) {
+    match WINIT_DISPLAY_LIST.lock().and_then(|mut v| Ok(*v = dpyinfo)) {
+        Err(e) => log::error!("failed to update winit_display_list: {e:?}"),
+        _ => {}
+    }
+}
+
+#[allow(unused_variables)]
+#[no_mangle]
+pub extern "C" fn winit_display_available() -> bool {
+    let display = winit_display_list();
+    !display.is_null()
+}
 
 #[allow(unused_variables)]
 #[no_mangle]
@@ -148,11 +175,12 @@ pub extern "C" fn check_x_display_info(obj: LispObject) -> DisplayInfoRef {
             return frame.display_info();
         }
 
-        if !unsafe { winit_display_list.is_null() } {
-            return unsafe { winit_display_list };
+        let winit_display_list = winit_display_list();
+        if !winit_display_list.is_null() {
+            return winit_display_list;
         }
 
-        error!("Webrender windows are not in use or not initialized");
+        error!("Winit frames are not in use or not initialized");
     }
 
     if let Some(terminal) = obj.as_terminal() {
@@ -167,7 +195,7 @@ pub extern "C" fn check_x_display_info(obj: LispObject) -> DisplayInfoRef {
 
     if let Some(display_name) = obj.as_string() {
         let display_name = display_name.to_string();
-        let mut dpyinfo = unsafe { winit_display_list };
+        let mut dpyinfo = winit_display_list();
 
         while !dpyinfo.is_null() {
             if dpyinfo
@@ -186,8 +214,9 @@ pub extern "C" fn check_x_display_info(obj: LispObject) -> DisplayInfoRef {
 
         x_open_connection(obj, Qnil, Qnil);
 
-        if !unsafe { winit_display_list.is_null() } {
-            return unsafe { winit_display_list };
+        let winit_display_list = winit_display_list();
+        if !winit_display_list.is_null() {
+            return winit_display_list;
         }
 
         error!("Display on {} not responding.", display_name);
@@ -517,10 +546,8 @@ pub fn x_open_connection(
     let mut display_info = winit_term_init(display);
 
     // Put this display on the chain.
-    unsafe {
-        display_info.next = winit_display_list.as_mut();
-        winit_display_list = display_info;
-    }
+    display_info.next = winit_display_list().as_mut();
+    set_winit_display_list(display_info);
     Qnil
 }
 

diff --git a/crates/winit/src/input.rs b/crates/winit/src/input.rs
@@ -13,7 +13,8 @@ use emacs_sys::globals::Qt;
 use emacs_sys::lisp::LispObject;
 use emacs_sys::sys::EmacsModifiers::down_modifier;
 use emacs_sys::sys::EmacsModifiers::up_modifier;
-use std::sync::OnceLock;
+use std::sync::LazyLock;
+use std::sync::Mutex;
 use winit::dpi::PhysicalPosition;
 use winit::event::ElementState;
 use winit::event::MouseButton;
@@ -23,22 +24,17 @@ use winit::keyboard::KeyCode;
 use winit::keyboard::ModifiersState;
 use winit::keyboard::PhysicalKey;
 
-static mut INPUT_STATE: OnceLock<InputProcessor> = OnceLock::new();
+static INPUT_STATE: LazyLock<Mutex<InputProcessor>> =
+    LazyLock::new(|| Mutex::new(InputProcessor::default()));
 impl InputProcessor {
-    pub fn global() -> &'static InputProcessor {
-        unsafe {
-            INPUT_STATE.get_or_init(|| {
-                log::trace!("INPUT_STATE is being created...");
-                InputProcessor {
-                    modifiers: ModifiersState::default(),
-                    total_delta: PhysicalPosition::new(0.0, 0.9),
-                }
-            })
-        }
-    }
-
     pub fn snapshot() -> InputProcessor {
-        Self::global().clone()
+        INPUT_STATE.lock().map_or_else(
+            |e| {
+                log::error!("Failed to snapshot INPUT_STATE {e:?}");
+                InputProcessor::default()
+            },
+            |s| s.clone(),
+        )
     }
 
     fn update(new_state: InputProcessor) {
@@ -47,13 +43,9 @@ impl InputProcessor {
             new_state.modifiers,
             new_state.total_delta
         );
-        unsafe {
-            let _ = INPUT_STATE.take();
-        };
-        if let Ok(_) = unsafe { INPUT_STATE.set(new_state) } {
-            log::debug!("Global input state changed");
-        } else {
-            log::error!("Failed to update input state");
+        match INPUT_STATE.lock().and_then(|mut s| Ok(*s = new_state)) {
+            Err(e) => log::error!("Failed to update INPUT_STATE: {e:?}"),
+            _ => {}
         }
     }
 }
@@ -64,6 +56,16 @@ pub struct InputProcessor {
     total_delta: PhysicalPosition<f64>,
 }
 
+impl Default for InputProcessor {
+    #[inline]
+    fn default() -> Self {
+        InputProcessor {
+            modifiers: ModifiersState::default(),
+            total_delta: PhysicalPosition::new(0.0, 0.9),
+        }
+    }
+}
+
 impl InputProcessor {
     pub fn handle_modifiers_changed(new_state: ModifiersState) {
         let snapshot = Self::snapshot();
@@ -96,14 +98,14 @@ impl InputProcessor {
     }
 
     fn get_modifiers() -> ModifiersState {
-        let InputProcessor { modifiers, .. } = Self::global();
+        let InputProcessor { modifiers, .. } = Self::snapshot();
         modifiers.clone()
     }
 }
 
 impl InputProcessor {
     pub fn handle_receive_char(c: char, top_frame: LispObject) -> Option<input_event> {
-        let state = Self::global();
+        let state = Self::snapshot();
 
         let iev: input_event = InputEvent {
             kind: event_kind::ASCII_KEYSTROKE_EVENT,
@@ -132,7 +134,7 @@ impl InputProcessor {
                 None
             }
             PhysicalKey::Code(key_code) => {
-                let InputProcessor { modifiers, .. } = Self::global().clone();
+                let InputProcessor { modifiers, .. } = Self::snapshot();
                 if keycode_to_emacs_key_name(key_code).is_null() {
                     return None;
                 }
@@ -184,7 +186,7 @@ impl InputProcessor {
             pos = frame.cursor_position();
         }
 
-        let InputProcessor { modifiers, .. } = Self::global();
+        let InputProcessor { modifiers, .. } = Self::snapshot();
         let iev: input_event = InputEvent {
             kind: event_kind::MOUSE_CLICK_EVENT,
             part: scroll_bar_part::scroll_bar_nowhere,
@@ -226,7 +228,7 @@ impl InputProcessor {
                 }
             }
             MouseScrollDelta::PixelDelta(pos) => {
-                let mut total_delta = Self::global().total_delta.clone();
+                let mut total_delta = Self::snapshot().total_delta.clone();
                 if phase != TouchPhase::Moved {
                     total_delta = PhysicalPosition::new(0.0, 0.0);
                 }

diff --git a/crates/winit/src/lib.rs b/crates/winit/src/lib.rs
@@ -1,5 +1,6 @@
 #![allow(non_camel_case_types, non_snake_case, non_upper_case_globals)]
 #![feature(concat_idents)]
+#![feature(lazy_cell)]
 #![allow(non_upper_case_globals)]
 
 #[macro_use]

diff --git a/src/frame.c b/src/frame.c
@@ -116,7 +116,11 @@ decode_any_frame (register Lisp_Object frame)
 bool
 display_available (void)
 {
+#ifdef HAVE_WINIT
+  return winit_display_available();
+#else
   return x_display_list != NULL;
+#endif
 }
 #endif
 

diff --git a/src/winitterm.h b/src/winitterm.h
@@ -81,9 +81,6 @@ struct winit_display_info
   void *gl_renderer_data;
 };
 
-extern struct winit_display_info *winit_display_list;
-#define x_display_list winit_display_list
-
 struct winit_output
 {
 
@@ -172,6 +169,7 @@ extern const char *app_bundle_relocate (const char *);
 
 /* Symbol initializations implemented in each pgtk sources. */
 extern void syms_of_winit_term(void);
+extern bool winit_display_available(void);
 
 #include "webrender_ffi.h"