From a58c796fc0fd27c4fe9bd1f099adaff8acef0859 Mon Sep 17 00:00:00 2001
From: Robbert van der Helm <mail@robbertvanderhelm.nl>
Date: Tue, 1 Mar 2022 15:00:32 +0100
Subject: [PATCH] Add an output slices field to Buffer

---
 src/buffer.rs               | 15 ++++++++-------
 src/wrapper/vst3/wrapper.rs | 11 +++++------
 2 files changed, 13 insertions(+), 13 deletions(-)

diff --git a/src/buffer.rs b/src/buffer.rs
index eff7554c..4085ab05 100644
--- a/src/buffer.rs
+++ b/src/buffer.rs
@@ -143,8 +143,8 @@ impl<'a> Buffer<'a> {
     /// The stored slices must point to live data when this object is passed to the plugins' process
     /// function. The rest of this object also assumes all channel lengths are equal. Panics will
     /// likely occur if this is not the case.
-    pub unsafe fn as_raw_vec(&mut self) -> &mut Vec<&'a mut [f32]> {
-        &mut self.output_slices
+    pub unsafe fn with_raw_vec(&mut self, update: impl FnOnce(&mut Vec<&'a mut [f32]>)) {
+        update(&mut self.output_slices);
     }
 }
 
@@ -200,11 +200,12 @@ mod miri {
     fn repeated_access() {
         let mut real_buffers = vec![vec![0.0; 512]; 2];
         let mut buffer = Buffer::default();
-        {
-            let slices = unsafe { buffer.as_raw_vec() };
-            let (first_channel, other_channels) = real_buffers.split_at_mut(1);
-            *slices = vec![&mut first_channel[0], &mut other_channels[0]];
-        }
+        unsafe {
+            buffer.with_raw_vec(|output_slices| {
+                let (first_channel, other_channels) = real_buffers.split_at_mut(1);
+                *output_slices = vec![&mut first_channel[0], &mut other_channels[0]];
+            })
+        };
 
         for samples in buffer.iter_mut() {
             for sample in samples {
diff --git a/src/wrapper/vst3/wrapper.rs b/src/wrapper/vst3/wrapper.rs
index a4e25320..49b52cb7 100644
--- a/src/wrapper/vst3/wrapper.rs
+++ b/src/wrapper/vst3/wrapper.rs
@@ -19,7 +19,6 @@ use super::inner::WrapperInner;
 use super::util::{VstPtr, BYPASS_PARAM_HASH, BYPASS_PARAM_ID};
 use super::view::WrapperView;
 use crate::param::internals::ParamPtr;
-use crate::param::range::Range;
 use crate::param::Param;
 use crate::plugin::{BufferConfig, BusConfig, NoteEvent, ProcessStatus, Vst3Plugin};
 use crate::wrapper::state::{ParamValue, State};
@@ -699,8 +698,9 @@ impl<P: Vst3Plugin> IAudioProcessor for Wrapper<P> {
             self.inner
                 .output_buffer
                 .write()
-                .as_raw_vec()
-                .resize_with(bus_config.num_output_channels as usize, || &mut []);
+                .with_raw_vec(|output_slices| {
+                    output_slices.resize_with(bus_config.num_output_channels as usize, || &mut [])
+                });
 
             // Also store this for later, so we can reinitialize the plugin after restoring state
             self.inner.current_buffer_config.store(Some(buffer_config));
@@ -829,8 +829,7 @@ impl<P: Vst3Plugin> IAudioProcessor for Wrapper<P> {
             // This vector has been reallocated to contain enough slices as there are output
             // channels
             let mut output_buffer = self.inner.output_buffer.write();
-            {
-                let output_slices = output_buffer.as_raw_vec();
+            output_buffer.with_raw_vec(|output_slices| {
                 nih_debug_assert_eq!(num_output_channels, output_slices.len());
                 for (output_channel_idx, output_channel_slice) in
                     output_slices.iter_mut().enumerate()
@@ -843,7 +842,7 @@ impl<P: Vst3Plugin> IAudioProcessor for Wrapper<P> {
                         data.num_samples as usize,
                     );
                 }
-            }
+            });
 
             // Most hosts process data in place, in which case we don't need to do any copying
             // ourselves. If the pointers do not alias, then we'll do the copy here and then the