Example yunq implementation for one Yellowstone endpoint.

rust/lib/yunq/src/buffer.rs

@@ -0,0 +1,60 @@
+use alloc::boxed::Box;
+use mammoth::syscall::ZError;
+
+pub struct ByteBuffer<const N: usize> {
+    buffer: Box<[u8; N]>,
+}
+
+impl<const N: usize> ByteBuffer<N> {
+    pub fn new() -> Self {
+        Self {
+            buffer: Box::new([0; N]),
+        }
+    }
+    pub fn size(&self) -> u64 {
+        N as u64
+    }
+
+    pub fn raw_ptr(&self) -> *const u8 {
+        self.buffer.as_ptr()
+    }
+
+    pub fn mut_ptr(&mut self) -> *mut u8 {
+        self.buffer.as_mut_ptr()
+    }
+
+    pub fn write_at<T>(&mut self, offset: usize, obj: T) -> Result<(), ZError> {
+        if (size_of::<T>() + offset) > N {
+            return Err(ZError::BUFFER_SIZE);
+        }
+        unsafe {
+            *(self.buffer[offset..].as_mut_ptr() as *mut T) = obj;
+        }
+        Ok(())
+    }
+
+    pub fn write_str_at(&mut self, offset: usize, s: &str) -> Result<(), ZError> {
+        if (s.len() + offset) > N {
+            return Err(ZError::BUFFER_SIZE);
+        }
+        for i in 0..s.len() {
+            self.buffer[offset + i] = s.as_bytes()[i];
+        }
+        Ok(())
+    }
+
+    pub fn at<T: Copy>(&self, offset: usize) -> Result<T, ZError> {
+        if (size_of::<T>() + offset) > N {
+            return Err(ZError::BUFFER_SIZE);
+        }
+        unsafe { Ok(*(self.buffer[offset..].as_ptr() as *const T)) }
+    }
+
+    pub fn str_at(&self, offset: usize, len: usize) -> Result<&str, ZError> {
+        if (len + offset) > N {
+            return Err(ZError::BUFFER_SIZE);
+        }
+        Ok(alloc::str::from_utf8(&self.buffer[offset..offset + len])
+            .map_err(|_| ZError::INVALID_ARGUMENT)?)
+    }
+}