Temporary fix to manage API_LEVEL_21 branch (head vs tag in builder)

Author: yogh333

ledger_secure_sdk_sys/build.rs

@@ -11,11 +11,10 @@ const DEFINES_CCID: [(&str, Option<&str>); 2] =
 
 const AUX_C_FILES: [&str; 2] = ["./src/c/src.c", "./src/c/sjlj.s"];
 
-const SDK_C_FILES: [&str; 9] = [
+const SDK_C_FILES: [&str; 8] = [
     "src/os_io_usb.c",
     "src/pic.c",
     "src/checks.c",
-    "lib_cxng/src/cx_exported_functions.c",
     "src/cx_stubs.S",
     "src/os.c",
     "src/svc_call.s",
@@ -212,8 +211,8 @@ fn retrieve_target_file_infos(
 fn clone_sdk(device: &Device) -> PathBuf {
     let (repo_url, sdk_branch) = match device {
         Device::NanoS => (
-            Path::new("https://github.com/LedgerHQ/nanos-secure-sdk"),
-            "master",
+            Path::new("https://github.com/LedgerHQ/ledger-secure-sdk"),
+            "API_LEVEL_LNS",
         ),
         Device::NanoX => (
             Path::new("https://github.com/LedgerHQ/ledger-secure-sdk"),
@@ -408,6 +407,14 @@ impl SDKBuilder {
         } else {
             // Let cc::Build determine CC from the environment variable
         }
+
+        // Test if the file  lib_cxng/src/cx_exported_functions.c exists
+        // If it does, add it to the list of files to compile
+        let cxng_src = self.bolos_sdk.join("lib_cxng/src/cx_exported_functions.c");
+        if cxng_src.exists() {
+            command.file(cxng_src);
+        }
+
         command
             .files(&AUX_C_FILES)
             .files(str2path(&self.bolos_sdk, &SDK_C_FILES))