From 086d07b8599fa4f226154187ec9ab47af6ee608f Mon Sep 17 00:00:00 2001
From: Eivind Alexander Bergem <eivind.bergem@inventas.no>
Date: Wed, 23 Aug 2023 08:45:54 +0200
Subject: [PATCH] Added `Buffer::channel_slice_mut()`

- Returns underlying channel buffer as mutable slice
- Enables writing to buffer
---
 src/buffer.rs | 17 +++++++++++++++++
 1 file changed, 17 insertions(+)

diff --git a/src/buffer.rs b/src/buffer.rs
index 8719da2..5b990f9 100644
--- a/src/buffer.rs
+++ b/src/buffer.rs
@@ -349,6 +349,23 @@ impl Buffer {
             }
         }
     }
+
+    /// Gets a mutable slice for the data from a channel.
+    pub fn channel_slice_mut<T>(&mut self, chan: &Channel) -> Option<&mut [T]> {
+        unsafe {
+            let begin = ffi::iio_buffer_first(self.buf, chan.chan) as *mut T;
+
+            if begin.is_null() {
+                None
+            } else {
+                let end = ffi::iio_buffer_end(self.buf) as *mut T;
+                let ptr = begin;
+                let size = end.offset_from(begin).abs() as usize;
+
+                Some(std::slice::from_raw_parts_mut(ptr, size))
+            }
+        }
+    }
 }
 
 /// Destroy the underlying buffer when the object scope ends.