src: handle NULL env scenario

Convert hard assertion into a throw with a useful error message in src/module_wrap.cc. PR-URL: #31899 Reviewed-By: Anna Henningsen <anna@addaleax.net>
nodejs · Mar 9, 2020 · cba75c5 · cba75c5
1 parent 862cd2b
commit cba75c5
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Showing 3 changed files with 43 additions and 24 deletions.
diff --git a/doc/api/errors.md b/doc/api/errors.md
@@ -889,6 +889,13 @@ provided.
 Encoding provided to `TextDecoder()` API was not one of the
 [WHATWG Supported Encodings][].
 
+<a id="ERR_EXECUTION_ENVIRONMENT_NOT_AVAILABLE"></a>
+### `ERR_EXECUTION_ENVIRONMENT_NOT_AVAILABLE`
+
+The JS execution context is not associated with a Node.js environment.
+This may occur when Node.js is used as an embedded library and some hooks
+for the JS engine are not set up properly.
+
 <a id="ERR_FALSY_VALUE_REJECTION"></a>
 ### `ERR_FALSY_VALUE_REJECTION`
 

diff --git a/src/module_wrap.cc b/src/module_wrap.cc
@@ -451,7 +451,12 @@ MaybeLocal<Module> ModuleWrap::ResolveCallback(Local<Context> context,
                                                Local<String> specifier,
                                                Local<Module> referrer) {
   Environment* env = Environment::GetCurrent(context);
-  CHECK_NOT_NULL(env);  // TODO(addaleax): Handle nullptr here.
+  if (env == nullptr) {
+    Isolate* isolate = context->GetIsolate();
+    THROW_ERR_EXECUTION_ENVIRONMENT_NOT_AVAILABLE(isolate);
+    return MaybeLocal<Module>();
+  }
+
   Isolate* isolate = env->isolate();
 
   ModuleWrap* dependent = GetFromModule(env, referrer);
@@ -1443,7 +1448,11 @@ static MaybeLocal<Promise> ImportModuleDynamically(
     Local<String> specifier) {
   Isolate* iso = context->GetIsolate();
   Environment* env = Environment::GetCurrent(context);
-  CHECK_NOT_NULL(env);  // TODO(addaleax): Handle nullptr here.
+  if (env == nullptr) {
+    THROW_ERR_EXECUTION_ENVIRONMENT_NOT_AVAILABLE(iso);
+    return MaybeLocal<Promise>();
+  }
+
   EscapableHandleScope handle_scope(iso);
 
   Local<Function> import_callback =

diff --git a/src/node_errors.h b/src/node_errors.h
@@ -39,6 +39,7 @@ void OnFatalError(const char* location, const char* message);
   V(ERR_CONSTRUCT_CALL_INVALID, TypeError)                                   \
   V(ERR_CRYPTO_UNKNOWN_CIPHER, Error)                                        \
   V(ERR_CRYPTO_UNKNOWN_DH_GROUP, Error)                                      \
+  V(ERR_EXECUTION_ENVIRONMENT_NOT_AVAILABLE, Error)                          \
   V(ERR_INVALID_ARG_VALUE, TypeError)                                        \
   V(ERR_OSSL_EVP_INVALID_DIGEST, Error)                                      \
   V(ERR_INVALID_ARG_TYPE, TypeError)                                         \
@@ -86,28 +87,30 @@ void OnFatalError(const char* location, const char* message);
 
 // Errors with predefined static messages
 
-#define PREDEFINED_ERROR_MESSAGES(V)                                         \
-  V(ERR_BUFFER_CONTEXT_NOT_AVAILABLE,                                        \
-    "Buffer is not available for the current Context")                       \
-  V(ERR_CONSTRUCT_CALL_INVALID, "Constructor cannot be called")              \
-  V(ERR_CONSTRUCT_CALL_REQUIRED, "Cannot call constructor without `new`")    \
-  V(ERR_CRYPTO_UNKNOWN_CIPHER, "Unknown cipher")                             \
-  V(ERR_CRYPTO_UNKNOWN_DH_GROUP, "Unknown DH group")                         \
-  V(ERR_INVALID_TRANSFER_OBJECT, "Found invalid object in transferList")     \
-  V(ERR_MEMORY_ALLOCATION_FAILED, "Failed to allocate memory")               \
-  V(ERR_OSSL_EVP_INVALID_DIGEST, "Invalid digest used")                      \
-  V(ERR_MISSING_MESSAGE_PORT_IN_TRANSFER_LIST,                               \
-    "MessagePort was found in message but not listed in transferList")       \
-  V(ERR_MISSING_PLATFORM_FOR_WORKER,                                         \
-    "The V8 platform used by this instance of Node does not support "        \
-    "creating Workers")                                                      \
-  V(ERR_NON_CONTEXT_AWARE_DISABLED,                                          \
-    "Loading non context-aware native modules has been disabled")            \
-  V(ERR_SCRIPT_EXECUTION_INTERRUPTED,                                        \
-    "Script execution was interrupted by `SIGINT`")                          \
-  V(ERR_TRANSFERRING_EXTERNALIZED_SHAREDARRAYBUFFER,                         \
-    "Cannot serialize externalized SharedArrayBuffer")                       \
-  V(ERR_TLS_PSK_SET_IDENTIY_HINT_FAILED, "Failed to set PSK identity hint")  \
+#define PREDEFINED_ERROR_MESSAGES(V)                                           \
+  V(ERR_BUFFER_CONTEXT_NOT_AVAILABLE,                                          \
+    "Buffer is not available for the current Context")                         \
+  V(ERR_CONSTRUCT_CALL_INVALID, "Constructor cannot be called")                \
+  V(ERR_CONSTRUCT_CALL_REQUIRED, "Cannot call constructor without `new`")      \
+  V(ERR_CRYPTO_UNKNOWN_CIPHER, "Unknown cipher")                               \
+  V(ERR_CRYPTO_UNKNOWN_DH_GROUP, "Unknown DH group")                           \
+  V(ERR_EXECUTION_ENVIRONMENT_NOT_AVAILABLE,                                   \
+    "Context not associated with Node.js environment")                         \
+  V(ERR_INVALID_TRANSFER_OBJECT, "Found invalid object in transferList")       \
+  V(ERR_MEMORY_ALLOCATION_FAILED, "Failed to allocate memory")                 \
+  V(ERR_OSSL_EVP_INVALID_DIGEST, "Invalid digest used")                        \
+  V(ERR_MISSING_MESSAGE_PORT_IN_TRANSFER_LIST,                                 \
+    "MessagePort was found in message but not listed in transferList")         \
+  V(ERR_MISSING_PLATFORM_FOR_WORKER,                                           \
+    "The V8 platform used by this instance of Node does not support "          \
+    "creating Workers")                                                        \
+  V(ERR_NON_CONTEXT_AWARE_DISABLED,                                            \
+    "Loading non context-aware native modules has been disabled")              \
+  V(ERR_SCRIPT_EXECUTION_INTERRUPTED,                                          \
+    "Script execution was interrupted by `SIGINT`")                            \
+  V(ERR_TRANSFERRING_EXTERNALIZED_SHAREDARRAYBUFFER,                           \
+    "Cannot serialize externalized SharedArrayBuffer")                         \
+  V(ERR_TLS_PSK_SET_IDENTIY_HINT_FAILED, "Failed to set PSK identity hint")
 
 #define V(code, message)                                                     \
   inline v8::Local<v8::Value> code(v8::Isolate* isolate) {                   \