use std::fs; use std::path::{Path, PathBuf}; fn get_api_version(libusb_source: &Path) { use std::io::BufRead; if let Ok(f) = fs::File::open(libusb_source) { let f = std::io::BufReader::new(f); for line in f.lines().flatten() { if line.starts_with("#define LIBUSB_API_VERSION") { if let Some(api_version) = line.rsplit(' ').next().and_then(|s| { if let Some(s) = s.strip_prefix("0x") { u32::from_str_radix(s, 16).ok() } else { None } }) { if api_version >= 0x01000108 { println!("cargo:rustc-cfg=libusb_hotplug_get_user_data"); } } break; } } } } fn main() { if let Ok(include_path) = std::env::var("DEP_USB_1.0_INCLUDE") { let path = PathBuf::from(include_path); get_api_version(path.join("libusb.h").as_path()); } }