From 4ceb0efdc490ad982e95afe7e6c1da557d942ca1 Mon Sep 17 00:00:00 2001
From: Robbert van der Helm <mail@robbertvanderhelm.nl>
Date: Thu, 3 Mar 2022 15:06:13 +0100
Subject: [PATCH] Use Arc instead of Box for the wrapper

We'll need this for the GuiContext.
---
 src/wrapper/clap/factory.rs | 6 +++++-
 src/wrapper/clap/plugin.rs  | 7 ++++---
 2 files changed, 9 insertions(+), 4 deletions(-)

diff --git a/src/wrapper/clap/factory.rs b/src/wrapper/clap/factory.rs
index c5f1938e..8f14d6d5 100644
--- a/src/wrapper/clap/factory.rs
+++ b/src/wrapper/clap/factory.rs
@@ -4,6 +4,7 @@ use clap_sys::plugin_factory::clap_plugin_factory;
 use std::ffi::CStr;
 use std::os::raw::c_char;
 use std::ptr;
+use std::sync::Arc;
 
 use super::descriptor::PluginDescriptor;
 use super::plugin::Wrapper;
@@ -60,7 +61,10 @@ impl<P: ClapPlugin> Factory<P> {
 
         if !plugin_id.is_null() && CStr::from_ptr(plugin_id) == factory.plugin_descriptor.clap_id()
         {
-            &Box::leak(Wrapper::<P>::new(host)).clap_plugin
+            // Arc does not have a convenient leak function like Box, so this gets a bit awkward
+            // This pointer gets turned into an Arc and its reference count decremented in
+            // [Wrapper::destroy()]
+            &(*Arc::into_raw(Wrapper::<P>::new(host))).clap_plugin
         } else {
             ptr::null()
         }
diff --git a/src/wrapper/clap/plugin.rs b/src/wrapper/clap/plugin.rs
index 2e8c5103..e28ea2f8 100644
--- a/src/wrapper/clap/plugin.rs
+++ b/src/wrapper/clap/plugin.rs
@@ -40,6 +40,7 @@ use std::ffi::{c_void, CStr};
 use std::os::raw::c_char;
 use std::ptr;
 use std::sync::atomic::{AtomicBool, AtomicU32, Ordering};
+use std::sync::Arc;
 use std::thread::{self, ThreadId};
 
 use super::context::WrapperProcessContext;
@@ -214,7 +215,7 @@ impl<P: ClapPlugin> MainThreadExecutor<Task> for Wrapper<P> {
 }
 
 impl<P: ClapPlugin> Wrapper<P> {
-    pub fn new(host_callback: *const clap_host) -> Box<Self> {
+    pub fn new(host_callback: *const clap_host) -> Arc<Self> {
         let plugin_descriptor = Box::new(PluginDescriptor::default());
 
         assert!(!host_callback.is_null());
@@ -371,7 +372,7 @@ impl<P: ClapPlugin> Wrapper<P> {
             .map(|(_, hash, ptr)| (*ptr, hash))
             .collect();
 
-        Box::new(wrapper)
+        Arc::new(wrapper)
     }
 
     fn make_process_context(&self) -> WrapperProcessContext<'_, P> {
@@ -515,7 +516,7 @@ impl<P: ClapPlugin> Wrapper<P> {
     }
 
     unsafe extern "C" fn destroy(plugin: *const clap_plugin) {
-        Box::from_raw(plugin as *mut Self);
+        Arc::from_raw(plugin as *mut Self);
     }
 
     unsafe extern "C" fn activate(