FIX: build iOS fixes, parse the CMake-generated options.h to extract all #define directives

crates/ccc-crypto-wolfssl/build.rs

@@ -171,6 +171,32 @@ fn build_wolfssl_cmake(source_dir: &Path, _out_dir: &Path) -> (PathBuf, PathBuf)
     (include_dir, lib_dir)
 }
 
+/// Parse the CMake-generated `options.h` to extract all `#define` directives.
+/// Returns a list of `-DNAME` clang args.
+fn parse_options_defines(include_dir: &Path) -> Vec<String> {
+    let options_h = include_dir.join("wolfssl/options.h");
+    if !options_h.exists() {
+        return Vec::new();
+    }
+
+    let content = std::fs::read_to_string(&options_h).expect("failed to read options.h");
+    let mut defines = Vec::new();
+    for line in content.lines() {
+        let line = line.trim();
+        if !line.starts_with("#define ") {
+            continue;
+        }
+        let rest = &line["#define ".len()..];
+        let name = rest.split_whitespace().next().unwrap_or("");
+        // Skip the header guard macro.
+        if name.is_empty() || name == "WOLFSSL_OPTIONS_H" {
+            continue;
+        }
+        defines.push(format!("-D{}", name));
+    }
+    defines
+}
+
 /// Run bindgen over the wolfCrypt headers we actually use.
 fn generate_bindings(include_dir: &Path, out_dir: &Path) {
     let header = include_dir.join("wolfssl/wolfcrypt/aes.h");
@@ -187,7 +213,17 @@ fn generate_bindings(include_dir: &Path, out_dir: &Path) {
         return;
     }
 
-    let bindings = bindgen::Builder::default()
+    // Parse the CMake-generated options.h so that bindgen's clang sees the
+    // exact same preprocessor flags as the compiled wolfSSL library.  This is
+    // essential for correct struct layout — e.g. GCM_TABLE_4BIT adds a 512-byte
+    // M0 table to the Gcm struct that changes the size of Aes.
+    let options_defines = parse_options_defines(include_dir);
+
+    // For cross-compilation, tell bindgen's clang the target triple so that
+    // platform-specific types (pointer size, alignment, builtins) are correct.
+    let target = env::var("TARGET").unwrap_or_default();
+
+    let mut builder = bindgen::Builder::default()
         // Include all wolfCrypt headers we need.
         .header(include_dir.join("wolfssl/wolfcrypt/aes.h").to_str().unwrap())
         .header(include_dir.join("wolfssl/wolfcrypt/chacha20_poly1305.h").to_str().unwrap())
@@ -201,31 +237,33 @@ fn generate_bindings(include_dir: &Path, out_dir: &Path) {
         .header(include_dir.join("wolfssl/wolfcrypt/curve25519.h").to_str().unwrap())
         .header(include_dir.join("wolfssl/wolfcrypt/curve448.h").to_str().unwrap())
         .header(include_dir.join("wolfssl/wolfcrypt/random.h").to_str().unwrap())
-        .clang_arg(format!("-I{}", include_dir.display()))
+        .clang_arg(format!("-I{}", include_dir.display()));
-        // Pass all required preprocessor defines explicitly so that bindgen's
+
-        // libclang sees the same feature flags as the C build, regardless of
+    // Pass all defines from the generated options.h.  This includes critical
-        // whether wolfSSL's options.h is correctly resolved by clang.
+    // struct-affecting flags like GCM_TABLE_4BIT, HAVE___UINT128_T,
-        //
+    // WOLFSSL_USE_ALIGN, etc. that change the layout of Gcm, Aes, and other types.
-        // AES-GCM (wc_AesGcmSetKey etc. are behind #ifdef HAVE_AESGCM)
+    for def in &options_defines {
-        .clang_arg("-DHAVE_AESGCM")
+        builder = builder.clang_arg(def);
-        // ChaCha20 / Poly1305 / XChaCha20
+    }
-        .clang_arg("-DHAVE_CHACHA")
+
-        .clang_arg("-DHAVE_POLY1305")
+    // Pass additional defines that are added via .cflag() in the CMake build
+    // (not cmake options, so they don't appear in options.h).
+    builder = builder
         .clang_arg("-DHAVE_XCHACHA")
-        // BLAKE2 is not a cmake option — enable via clang preprocessor flags
-        // so that the headers expose the BLAKE2b/BLAKE2s function prototypes.
         .clang_arg("-DHAVE_BLAKE2")
-        .clang_arg("-DHAVE_BLAKE2B")
+        .clang_arg("-DHAVE_BLAKE2B");
-        // Required so sha512.h exposes SHA384 typedef + functions.
+
-        .clang_arg("-DWOLFSSL_SHA384")
+    // Set the cross-compilation target if it differs from the host.
-        .clang_arg("-DWOLFSSL_SHA512")
+    if !target.is_empty() {
-        // SHA3 functions (wc_InitSha3_256, etc.)
+        // Map Rust target triples to clang-compatible triples.
-        .clang_arg("-DWOLFSSL_SHA3")
+        let clang_target = match target.as_str() {
-        // HKDF via TLS-1.3 primitives (wc_Tls13_HKDF_Extract/Expand_Label)
+            "aarch64-apple-ios-sim" => "arm64-apple-ios-simulator".to_string(),
-        .clang_arg("-DHAVE_HKDF")
+            other => other.to_string(),
-        // Curve25519 / Curve448 need HAVE_CURVE25519 / HAVE_CURVE448
+        };
-        .clang_arg("-DHAVE_CURVE25519")
+        builder = builder.clang_arg(format!("--target={}", clang_target));
-        .clang_arg("-DHAVE_CURVE448")
+    }
+
+    let bindings = builder
         // Only generate bindings for the types/functions we use.
         .allowlist_function("wc_Aes.*")
         .allowlist_function("wc_AesGcm.*")