Reset StreamWrapper after calling mz_inflate / mz_deflate

src/ffi/c.rs

@@ -221,6 +221,12 @@ impl InflateBackend for Inflate {
 
         let rc = unsafe { mz_inflate(raw, flush as c_int) };
 
+        // reset these pointers so we don't accidentally read them later
+        raw.next_in = ptr::null_mut();
+        raw.avail_in = 0;
+        raw.next_out = ptr::null_mut();
+        raw.avail_out = 0;
+
         // Unfortunately the total counters provided by zlib might be only
         // 32 bits wide and overflow while processing large amounts of data.
         self.inner.total_in += (raw.next_in as usize - input.as_ptr() as usize) as u64;
@@ -309,6 +315,12 @@ impl DeflateBackend for Deflate {
 
         let rc = unsafe { mz_deflate(raw, flush as c_int) };
 
+        // reset these pointers so we don't accidentally read them later
+        raw.next_in = ptr::null_mut();
+        raw.avail_in = 0;
+        raw.next_out = ptr::null_mut();
+        raw.avail_out = 0;
+
         // Unfortunately the total counters provided by zlib might be only
         // 32 bits wide and overflow while processing large amounts of data.
         self.inner.total_in += (raw.next_in as usize - input.as_ptr() as usize) as u64;