use std::fs::metadata to get file size in tests

Author: folkertdev

test-libz-rs-sys/src/gz.rs

@@ -2033,25 +2033,8 @@ fn gzrewind_error() {
 //
 // - `Ok(size)` on success.
 // - `Err` on error.
-fn file_size(path: &str) -> Result<usize, ()> {
-    let mut result = Err(());
-    let stat_ptr = unsafe { libc::calloc(1, core::mem::size_of::<libc::stat>() as _) };
-    if stat_ptr.is_null() {
-        return result;
-    }
-    let ret = unsafe {
-        libc::stat(
-            CString::new(path).unwrap().as_ptr(),
-            stat_ptr.cast::<libc::stat>(),
-        )
-    };
-    if ret == 0 {
-        if let Some(stat_info) = unsafe { stat_ptr.cast::<libc::stat>().as_ref() } {
-            result = Ok(stat_info.st_size as usize);
-        }
-    }
-    unsafe { libc::free(stat_ptr) };
-    result
+fn file_size(path: &str) -> Result<usize, std::io::Error> {
+    Ok(std::fs::metadata(path)?.len() as usize)
 }
 
 #[cfg(feature = "gzprintf")]