Function convert

block/src/qcow/mod.rs:2302–2322

Copy the contents of a disk image in `src_file` into `dst_file`. The type of `src_file` is automatically detected, and the output file type is determined by `dst_type`.

(
    mut src_file: RawFile,
    dst_file: RawFile,
    dst_type: ImageType,
    src_max_nesting_depth: u32,
)

/// The type of `src_file` is automatically detected, and the output file type is
/// determined by `dst_type`.
pub fn convert(
    mut src_file: RawFile,
    dst_file: RawFile,
    dst_type: ImageType,
    src_max_nesting_depth: u32,
) -> BlockResult<()> {
    let src_type = detect_image_type(&mut src_file)?;
    match src_type {
        ImageType::Qcow2 => {
            let mut src_reader =
                QcowFile::from_with_nesting_depth(src_file, src_max_nesting_depth, true)
                    .map_err(|e| BlockError::new(BlockErrorKind::Io, e))?;
            convert_reader(&mut src_reader, dst_file, dst_type)
        }
        ImageType::Raw => {
            // src_file is a raw file.
            let mut src_reader = src_file;
            convert_reader(&mut src_reader, dst_file, dst_type)
        }
    }
}

/// Detect the type of an image file by checking for a valid qcow2 header.
pub fn detect_image_type(file: &mut RawFile) -> BlockResult<ImageType> {