Start 'fuzzing' of dart:io APIs and fix first issue found.

runtime/vm/dart_api_message.cc

 // Copyright (c) 2012, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
 #include "vm/dart_api_message.h"
 #include "vm/object.h"
 #include "vm/object_store.h"
 
 namespace dart {
 
@@ skipping 44 matching lines @@
 
 Dart_CObject* ApiMessageReader::AllocateDartCObject(Dart_CObject::Type type) {
   Dart_CObject* value =
       reinterpret_cast<Dart_CObject*>(alloc_(NULL, 0, sizeof(Dart_CObject)));
   ASSERT(value != NULL);
   value->type = type;
   return value;
 }
 
 
+Dart_CObject* ApiMessageReader::AllocateDartCObjectUnsupported() {
+  return AllocateDartCObject(Dart_CObject::kUnsupported);
+}
+
+
 Dart_CObject* ApiMessageReader::AllocateDartCObjectNull() {
   return AllocateDartCObject(Dart_CObject::kNull);
 }
 
 
 Dart_CObject* ApiMessageReader::AllocateDartCObjectBool(bool val) {
   Dart_CObject* value = AllocateDartCObject(Dart_CObject::kBool);
   value->value.as_bool = val;
   return value;
 }
@@ skipping 88 matching lines @@
 
 Dart_CObject* ApiMessageReader::ReadInlinedObject(intptr_t object_id) {
   // Read the class header information and lookup the class.
   intptr_t class_header = ReadIntptrValue();
   intptr_t tags = ReadIntptrValue();
   USE(tags);
   intptr_t class_id;
 
   // Reading of regular dart instances is not supported.
   if (SerializedHeaderData::decode(class_header) == kInstanceId) {
-    return NULL;
+    return AllocateDartCObjectUnsupported();
   }
 
   ASSERT((class_header & kSmiTagMask) != 0);
   class_id = LookupInternalClass(class_header);
   switch (class_id) {
     case Object::kClassClass: {
-      return NULL;
+      return AllocateDartCObjectUnsupported();
     }
     case Object::kTypeArgumentsClass: {
       // TODO(sjesse): Remove this when message serialization format is
       // updated (currently length is leaked).
       Dart_CObject* value = &type_arguments_marker;
       AddBackwardReference(object_id, value);
       Dart_CObject* length = ReadObject();
       ASSERT(length->type == Dart_CObject::kInt32);
       for (int i = 0; i < length->value.as_int32; i++) {
         Dart_CObject* type = ReadObject();
         if (type != &dynamic_type_marker) {
-          return NULL;
+          return AllocateDartCObjectUnsupported();
         }
       }
       return value;
     }
     case Object::kTypeParameterClass: {
       // TODO(sgjesse): Fix this workaround ignoring the type parameter.
       Dart_CObject* value = &dynamic_type_marker;
       AddBackwardReference(object_id, value);
       intptr_t index = ReadIntptrValue();
       USE(index);
@@ skipping 11 matching lines @@
     case ObjectStore::kArrayClass: {
       intptr_t len = ReadSmiValue();
       Dart_CObject* value = AllocateDartCObjectArray(len);
       AddBackwardReference(object_id, value);
       // Skip type arguments.
       // TODO(sjesse): Remove this when message serialization format is
       // updated (currently type_arguments is leaked).
       Dart_CObject* type_arguments = ReadObject();
       if (type_arguments != &type_arguments_marker &&
           type_arguments->type != Dart_CObject::kNull) {
-        return NULL;
+        return AllocateDartCObjectUnsupported();
       }
       for (int i = 0; i < len; i++) {
         value->value.as_array.values[i] = ReadObject();
       }
       return value;
     }
     case ObjectStore::kMintClass: {
       int64_t value = Read<int64_t>();
       Dart_CObject* object;
       if (kMinInt32 <= value && value <= kMaxInt32) {
@@ skipping 30 matching lines @@
       AddBackwardReference(object_id, object);
       char* p = object->value.as_string;
       for (intptr_t i = 0; i < len; i++) {
         p[i] = Read<uint8_t>();
       }
       p[len] = '\0';
       return object;
     }
     case ObjectStore::kTwoByteStringClass:
       // Two byte strings not supported.
-      return NULL;
+      return AllocateDartCObjectUnsupported();
     case ObjectStore::kFourByteStringClass:
       // Four byte strings not supported.
-      return NULL;
+      return AllocateDartCObjectUnsupported();
     case ObjectStore::kUint8ArrayClass: {
       intptr_t len = ReadSmiValue();
       Dart_CObject* object = AllocateDartCObjectUint8Array(len);
       AddBackwardReference(object_id, object);
       if (len > 0) {
         uint8_t* p = object->value.as_byte_array.values;
         for (intptr_t i = 0; i < len; i++) {
           p[i] = Read<uint8_t>();
         }
       }
       return object;
     }
     default:
       // Everything else not supported.
-      return NULL;
+      return AllocateDartCObjectUnsupported();
   }
 }
 
 
 Dart_CObject* ApiMessageReader::ReadIndexedObject(intptr_t object_id) {
   if (object_id == Object::kNullObject) {
     return AllocateDartCObjectNull();
-  } else if (object_id == ObjectStore::kTrueValue) {
+  }
+  if (object_id == ObjectStore::kTrueValue) {
     return AllocateDartCObjectBool(true);
-  } else if (object_id == ObjectStore::kFalseValue) {
+  }
+  if (object_id == ObjectStore::kFalseValue) {
     return AllocateDartCObjectBool(false);
-  } else if (object_id == ObjectStore::kDynamicType ||
-             object_id == ObjectStore::kDoubleInterface ||
-             object_id == ObjectStore::kIntInterface ||
-             object_id == ObjectStore::kBoolInterface ||
-             object_id == ObjectStore::kStringInterface) {
+  }
+  if (object_id == ObjectStore::kDynamicType ||
+      object_id == ObjectStore::kDoubleInterface ||
+      object_id == ObjectStore::kIntInterface ||
+      object_id == ObjectStore::kBoolInterface ||
+      object_id == ObjectStore::kStringInterface) {
     // Always return dynamic type (this is only a marker).
     return &dynamic_type_marker;
-  } else {
-    intptr_t index = object_id - kMaxPredefinedObjectIds;
-    ASSERT((0 <= index) && (index < backward_references_.length()));
-    ASSERT(backward_references_[index] != NULL);
-    return backward_references_[index];
   }
-  return NULL;
+  intptr_t index = object_id - kMaxPredefinedObjectIds;
+  ASSERT((0 <= index) && (index < backward_references_.length()));
+  ASSERT(backward_references_[index] != NULL);
+  return backward_references_[index];
 }
 
 
 Dart_CObject* ApiMessageReader::ReadObjectImpl(intptr_t header) {
   SerializedHeaderType header_type = SerializedHeaderTag::decode(header);
   intptr_t header_value = SerializedHeaderData::decode(header);
 
   if (header_type == kObjectId) {
     return ReadIndexedObject(header_value);
   }
@@ skipping 228 matching lines @@
 }
 
 
 void ApiMessageWriter::WriteCMessage(Dart_CObject* object) {
   WriteCObject(object);
   UnmarkAllCObjects(object);
   FinalizeBuffer();
 }
 
 }  // namespace dart