Function fz_open_memory 

pub unsafe extern "C" fn fz_open_memory(
    ctx: *mut fz_context,
    data: *const c_uchar,
    len: usize,
) -> *mut fz_stream

Open a block of memory as a stream.

data: Pointer to start of data block. Ownership of the data
block is NOT passed in.

len: Number of bytes in data block.

Returns pointer to newly created stream. May throw exceptions on
failure to allocate.