DashInterface, DashInterfaceEmulated

wlx-common/src/handle.rs

@@ -0,0 +1,176 @@
+#[macro_export]
+macro_rules! gen_id {
+    (
+		$container_name:ident,
+		$instance_name:ident,
+		$cell_name:ident,
+		$handle_name:ident) => {
+        //ThingCell
+        #[derive(Debug)]
+        pub struct $cell_name {
+            pub obj: $instance_name,
+            pub generation: u64,
+        }
+
+        //ThingVec
+        #[derive(Debug)]
+        pub struct $container_name {
+            // Vec<Option<ThingCell>>
+            pub vec: Vec<Option<$cell_name>>,
+
+            cur_generation: u64,
+        }
+
+        //ThingHandle
+        #[derive(Default, Debug, Clone, Copy, PartialEq, Hash, Eq)]
+        pub struct $handle_name {
+            idx: u32,
+            generation: u64,
+        }
+
+        #[allow(dead_code)]
+        impl $handle_name {
+            pub const fn reset(&mut self) {
+                self.generation = 0;
+            }
+
+            pub const fn is_set(&self) -> bool {
+                self.generation > 0
+            }
+
+            pub const fn id(&self) -> u32 {
+                self.idx
+            }
+
+            pub const fn new(idx: u32, generation: u64) -> Self {
+                Self { idx, generation }
+            }
+        }
+
+        //ThingVec
+        impl $container_name {
+            pub const fn new() -> Self {
+                Self {
+                    vec: Vec::new(),
+                    cur_generation: 0,
+                }
+            }
+
+            pub fn iter(&self) -> impl Iterator<Item = ($handle_name, &$instance_name)> {
+                self.vec.iter().enumerate().filter_map(|(idx, opt_cell)| {
+                    opt_cell.as_ref().map(|cell| {
+                        let handle = $container_name::get_handle(&cell, idx);
+                        (handle, &cell.obj)
+                    })
+                })
+            }
+
+            pub fn iter_mut(
+                &mut self,
+            ) -> impl Iterator<Item = ($handle_name, &mut $instance_name)> {
+                self.vec
+                    .iter_mut()
+                    .enumerate()
+                    .filter_map(|(idx, opt_cell)| {
+                        opt_cell.as_mut().map(|cell| {
+                            let handle = $container_name::get_handle(&cell, idx);
+                            (handle, &mut cell.obj)
+                        })
+                    })
+            }
+
+            pub const fn get_handle(cell: &$cell_name, idx: usize) -> $handle_name {
+                $handle_name {
+                    idx: idx as u32,
+                    generation: cell.generation,
+                }
+            }
+
+            fn find_unused_idx(&mut self) -> Option<u32> {
+                for (num, obj) in self.vec.iter().enumerate() {
+                    if obj.is_none() {
+                        return Some(num as u32);
+                    }
+                }
+                None
+            }
+
+            pub fn add(&mut self, obj: $instance_name) -> $handle_name {
+                self.cur_generation += 1;
+                let generation = self.cur_generation;
+
+                let unused_idx = self.find_unused_idx();
+
+                let idx = if let Some(idx) = unused_idx {
+                    idx
+                } else {
+                    self.vec.len() as u32
+                };
+
+                let handle = $handle_name { idx, generation };
+
+                let cell = $cell_name { obj, generation };
+
+                if let Some(idx) = unused_idx {
+                    self.vec[idx as usize] = Some(cell);
+                } else {
+                    self.vec.push(Some(cell))
+                }
+
+                handle
+            }
+
+            pub fn remove(&mut self, handle: &$handle_name) {
+                // Out of bounds, ignore
+                if handle.idx as usize >= self.vec.len() {
+                    return;
+                }
+
+                // Remove only if the generation matches
+                if let Some(cell) = &self.vec[handle.idx as usize] {
+                    if cell.generation == handle.generation {
+                        self.vec[handle.idx as usize] = None;
+                    }
+                }
+            }
+
+            pub fn get(&self, handle: &$handle_name) -> Option<&$instance_name> {
+                // Out of bounds, ignore
+                if handle.idx as usize >= self.vec.len() {
+                    return None;
+                }
+
+                if let Some(cell) = &self.vec[handle.idx as usize] {
+                    if cell.generation == handle.generation {
+                        return Some(&cell.obj);
+                    }
+                }
+
+                None
+            }
+
+            pub fn get_mut(&mut self, handle: &$handle_name) -> Option<&mut $instance_name> {
+                // Out of bounds, ignore
+                if handle.idx as usize >= self.vec.len() {
+                    return None;
+                }
+
+                if let Some(cell) = &mut self.vec[handle.idx as usize] {
+                    if cell.generation == handle.generation {
+                        return Some(&mut cell.obj);
+                    }
+                }
+
+                None
+            }
+        }
+    };
+}
+
+/* Example usage:
+gen_id!(ThingVec, ThingInstance, ThingCell, ThingHandle);
+
+struct ThingInstance {}
+
+impl ThingInstance {}
+ */