chore: establish development baseline

crates/bat-ffi/Cargo.toml

@@ -0,0 +1,24 @@
+[package]
+name = "bat-ffi"
+version.workspace = true
+edition.workspace = true
+authors.workspace = true
+license.workspace = true
+
+[lib]
+crate-type = ["cdylib", "staticlib"]
+
+[dependencies]
+bat-cas-engine = { path = "../bat-cas-engine" }
+bat-assetbundle = { path = "../bat-assetbundle" }
+bat-patch = { path = "../bat-patch" }
+
+anyhow.workspace = true
+serde.workspace = true
+serde_json.workspace = true
+
+# FFI 绑定
+libc = "0.2"
+
+[build-dependencies]
+cbindgen = "0.27"

crates/bat-ffi/src/lib.rs

@@ -0,0 +1,50 @@
+//! # BAT FFI
+//!
+//! Go 和 Rust 之间的 FFI 绑定层
+//!
+//! 导出 C ABI 接口供 Go 通过 CGO 调用
+
+#![warn(clippy::all)]
+
+use std::ffi::CString;
+use std::os::raw::c_char;
+
+/// FFI 版本号
+pub const VERSION: &str = env!("CARGO_PKG_VERSION");
+
+/// 获取版本号（C ABI）
+#[no_mangle]
+pub extern "C" fn bat_version() -> *const c_char {
+    CString::new(VERSION).unwrap().into_raw()
+}
+
+/// 释放 C 字符串内存
+///
+/// # Safety
+/// 调用者必须确保：
+/// - `s` 是通过 `bat_version` 返回的有效指针
+/// - `s` 只被释放一次
+#[no_mangle]
+pub unsafe extern "C" fn bat_free_string(s: *mut c_char) {
+    if !s.is_null() {
+        let _ = CString::from_raw(s);
+    }
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+    use std::ffi::CStr;
+
+    #[test]
+    fn test_ffi_version() {
+        let version_ptr = bat_version();
+        assert!(!version_ptr.is_null());
+
+        unsafe {
+            let version_cstr = CStr::from_ptr(version_ptr);
+            let version = version_cstr.to_str().unwrap();
+            assert!(!version.is_empty());
+        }
+    }
+}