src: fix --disable-single-executable-application

Previously it would not compile if the build is configured with --disable-single-executable-application because we use directives to exclude the definition of SEA-related code completely. This patch changes them so that the SEA code are still compiled and internals can still check whether the executable is an SEA. The executable would not try to load the SEA blob at all if SEA is disabled. If future modifications to the C++ code attempt to load the SEA blob when SEA is disabled, UNREACHABLE() would be raised. If user attempt to generate the SEA blob with --experimental-sea-config with an executable that disables SEA, they would get an error. PR-URL: #51808 Fixes: #51730 Reviewed-By: Tobias Nießen <tniessen@tnie.de>

Author: joyeecheung

src/node.cc

@@ -1441,13 +1441,16 @@ static ExitCode StartInternal(int argc, char** argv) {
  });
 
  uv_loop_configure(uv_default_loop(), UV_METRICS_IDLE_TIME);
-
  std::string sea_config = per_process::cli_options->experimental_sea_config;
  if (!sea_config.empty()) {
+#if !defined(DISABLE_SINGLE_EXECUTABLE_APPLICATION)
  return sea::BuildSingleExecutableBlob(
  sea_config, result->args(), result->exec_args());
+#else
+ fprintf(stderr, "Single executable application is disabled.\n");
+ return ExitCode::kGenericUserError;
+#endif // !defined(DISABLE_SINGLE_EXECUTABLE_APPLICATION)
  }
-
  // --build-snapshot indicates that we are in snapshot building mode.
  if (per_process::cli_options->per_isolate->build_snapshot) {
  if (per_process::cli_options->per_isolate->build_snapshot_config.empty() &&

src/node_sea.cc

@@ -27,8 +27,6 @@
 #include <tuple>
 #include <vector>
 
-#if !defined(DISABLE_SINGLE_EXECUTABLE_APPLICATION)
-
 using node::ExitCode;
 using v8::ArrayBuffer;
 using v8::BackingStore;
@@ -189,6 +187,7 @@ SeaResource SeaDeserializer::Read() {
 }
 
 std::string_view FindSingleExecutableBlob() {
+#if !defined(DISABLE_SINGLE_EXECUTABLE_APPLICATION)
  CHECK(IsSingleExecutable());
  static const std::string_view result = []() -> std::string_view {
  size_t size;
@@ -209,6 +208,9 @@ std::string_view FindSingleExecutableBlob() {
  result.data(),
  result.size());
  return result;
+#else
+ UNREACHABLE();
+#endif // !defined(DISABLE_SINGLE_EXECUTABLE_APPLICATION)
 }
 
 } // anonymous namespace
@@ -668,5 +670,3 @@ void RegisterExternalReferences(ExternalReferenceRegistry* registry) {
 
 NODE_BINDING_CONTEXT_AWARE_INTERNAL(sea, node::sea::Initialize)
 NODE_BINDING_EXTERNAL_REFERENCE(sea, node::sea::RegisterExternalReferences)
-
-#endif // !defined(DISABLE_SINGLE_EXECUTABLE_APPLICATION)

src/node_sea.h

@@ -3,8 +3,6 @@
 
 #if defined(NODE_WANT_INTERNALS) && NODE_WANT_INTERNALS
 
-#if !defined(DISABLE_SINGLE_EXECUTABLE_APPLICATION)
-
 #include <cinttypes>
 #include <optional>
 #include <string>
@@ -52,8 +50,6 @@ node::ExitCode BuildSingleExecutableBlob(
 } // namespace sea
 } // namespace node
 
-#endif // !defined(DISABLE_SINGLE_EXECUTABLE_APPLICATION)
-
 #endif // defined(NODE_WANT_INTERNALS) && NODE_WANT_INTERNALS
 
 #endif // SRC_NODE_SEA_H_