recursive: bool,
}
-/// How large a buffer to pre-allocate before reading the entire file at `path`.
-fn initial_buffer_size<P: AsRef<Path>>(path: P) -> usize {
+/// How large a buffer to pre-allocate before reading the entire file.
+fn initial_buffer_size(file: &File) -> usize {
// Allocate one extra byte so the buffer doesn't need to grow before the
// final `read` call at the end of the file. Don't worry about `usize`
// overflow because reading will fail regardless in that case.
- metadata(path).map(|m| m.len() as usize + 1).unwrap_or(0)
+ file.metadata().map(|m| m.len() as usize + 1).unwrap_or(0)
}
/// Read the entire contents of a file into a bytes vector.
/// ```
#[unstable(feature = "fs_read_write", issue = "46588")]
pub fn read<P: AsRef<Path>>(path: P) -> io::Result<Vec<u8>> {
- let mut bytes = Vec::with_capacity(initial_buffer_size(&path));
- File::open(path)?.read_to_end(&mut bytes)?;
+ let mut file = File::open(path)?;
+ let mut bytes = Vec::with_capacity(initial_buffer_size(&file));
+ file.read_to_end(&mut bytes)?;
Ok(bytes)
}
/// ```
#[unstable(feature = "fs_read_write", issue = "46588")]
pub fn read_string<P: AsRef<Path>>(path: P) -> io::Result<String> {
- let mut string = String::with_capacity(initial_buffer_size(&path));
- File::open(path)?.read_to_string(&mut string)?;
+ let mut file = File::open(path)?;
+ let mut string = String::with_capacity(initial_buffer_size(&file));
+ file.read_to_string(&mut string)?;
Ok(string)
}