Issue 5137 - [emscripten] Added basic filter storage implementation

compiled/bindings/generator.cpp

 /*
  * This file is part of Adblock Plus <https://adblockplus.org/>,
- * Copyright (C) 2006-2017 eyeo GmbH
+ * Copyright (C) 2006-present eyeo GmbH
  *
  * Adblock Plus is free software: you can redistribute it and/or modify
  * it under the terms of the GNU General Public License version 3 as
  * published by the Free Software Foundation.
  *
  * Adblock Plus is distributed in the hope that it will be useful,
  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  * GNU General Public License for more details.
  *
  * You should have received a copy of the GNU General Public License
  * along with Adblock Plus.  If not, see <http://www.gnu.org/licenses/>.
  */
 
 #include <cstdio>
 
-#include <emscripten.h>
-
 #include "generator.h"
+#include "library.h"
 
 namespace
 {
   std::vector<bindings_internal::ClassInfo> classes;
-  std::vector<bindings_internal::NamespaceInfo> namespaces;
-
-  void printProperties(const bindings_internal::PropertyList& properties)
-  {
-    for (const auto& property : properties)
-    {
-      if (property.jsValue.empty())
-      {
-        printf("get %s%s,\n", property.name.c_str(),
-               wrapCall(property.getter, false).c_str());
-        if (!property.setter.empty())
-        {
-          printf("set %s%s,\n", property.name.c_str(),
-                 wrapCall(property.setter, false).c_str());
-        }
-      }
-      else
-        printf("%s: %s,\n", property.name.c_str(), property.jsValue.c_str());
-    }
-  }
-
-  void printMethods(const bindings_internal::MethodList& methods,
-                    bool instanceOnly = true)
-  {
-    for (const auto& method : methods)
-      if (!instanceOnly || method.call.instance_function)
-        printf("%s: %s,\n", method.name.c_str(), wrapCall(method.call).c_str());
-  }
 }
 
 namespace bindings_internal
 {
   FunctionInfo::FunctionInfo()
   {
-    name[0] = '\0';
   }
 
   FunctionInfo::FunctionInfo(TypeCategory returnType, TYPEID pointerType,
       std::initializer_list<TypeCategory> argTypes, bool instance_function,
       void* function)
       : returnType(returnType), pointerType(pointerType),
         instance_function(instance_function)
   {
-    name[0] = '\0';
-
     // The function parameter is a pointer to the function pointer.
     // Emscripten's "function pointers" are actually integers indicating the
     // position in the call table. 0 represents nullptr.
     if (!*reinterpret_cast<int*>(function))
       return;
 
     std::string signature;
 
     // Add return type to the signature. Similar logic in Emscripten:
     // https://github.com/kripken/emscripten/blob/1.37.3/src/modules.js#L46
@@ skipping 52 matching lines @@
           break;
         case TypeCategory::DOUBLE:
           signature += 'd';
           break;
         default:
           throw std::runtime_error("Unexpected function argument type");
       }
       args.push_back(type);
     }
 
-    get_function_name(function, signature.c_str());
+    int nameLength = GetFunctionName(nullptr, function, signature.c_str());
+    name.resize(nameLength);
+    GetFunctionName(name.data(), function, signature.c_str());
   }
 
   bool FunctionInfo::empty() const
   {
-    return name[0] == '\0';
-  }
-
-  void FunctionInfo::get_function_name(void* ptr, const char* signature)
-  {
-    // This is a hack, C++ won't let us get the mangled function name.
-    // JavaScript is more dynamic so we pass the pointer to our function
-    // there. With that and the function signature we can call the function -
-    // with a full stack so that we will cause it to abort. Sometimes the
-    // function we are calling will also be missing from the build. The result
-    // is the same: abort() is called which in turn calls stackTrace(). By
-    // replacing stackTrace() we get access to the call stack and search it
-    // for the name of our function.
-
-    EM_ASM_ARGS({
-      var signature = AsciiToString($2);
-      var args = [];
-      for (var i = 1; i < signature.length; i++)
-        args.push(0);
-
-      var oldPrint = Module.print;
-      var oldPrintErr = Module.printErr;
-      var oldStackTrace = stackTrace;
-      var sp = Runtime.stackSave();
-      Module.print = function(){};
-      Module.printErr = function(){};
-      stackTrace = function()
-      {
-        var stack = [];
-        for (var f = arguments.callee.caller; f; f = f.caller)
-        {
-          if (f.name)
-          {
-            if (f.name.indexOf("dynCall") == 0)
-              break;
-            else
-              stack.push(f.name);
-          }
-        }
-
-        result = stack[stack.length - 1];
-        if (result && result.indexOf("__wrapper") >= 0)
-          result = stack[stack.length - 2];
-        throw result;
-      };
-
-      Runtime.stackRestore(STACK_MAX);
-
-      try
-      {
-        Runtime.dynCall(signature, HEAP32[$1 >> 2], args);
-      }
-      catch(e)
-      {
-        Module.stringToAscii(e, $0);
-      }
-      finally
-      {
-        Runtime.stackRestore(sp);
-        Module.print = oldPrint;
-        Module.printErr = oldPrintErr;
-        stackTrace = oldStackTrace;
-      }
-    }, name, ptr, signature);
+    return name.empty();
   }
 
   ClassInfo* find_class(TYPEID classID)
   {
     for (auto& classInfo : classes)
       if (classInfo.id == classID)
         return &classInfo;
     return nullptr;
   }
 
   void register_class(const char* name, TYPEID classID, TYPEID baseClassID,
-                      ptrdiff_t ref_counted_offset)
+                      ptrdiff_t ref_counted_offset,
+                      const FunctionInfo& instanceGetter)
   {
     if (find_class(classID))
       throw std::runtime_error(std::string("Duplicate definition for class ") + name);
 
     if (baseClassID != TypeInfo<NoBaseClass>() && !find_class(baseClassID))
       throw std::runtime_error(std::string("Unknown base class defined for class ") + name);
 
     ClassInfo classInfo;
     classInfo.id = classID;
     classInfo.baseClass = baseClassID;
     classInfo.name = name;
     classInfo.subclass_differentiator.offset = SIZE_MAX;
     classInfo.ref_counted_offset = ref_counted_offset;
+    classInfo.instanceGetter = instanceGetter;
     classes.push_back(classInfo);
   }
 
   void register_property(TYPEID classID, const char* name,
       const FunctionInfo& getter, const FunctionInfo& setter,
       const char* jsValue)
   {
     ClassInfo* classInfo = find_class(classID);
     if (!classInfo)
       throw std::runtime_error(std::string("Property defined on unknown class: ") + name);
@@ skipping 26 matching lines @@
     if (!classInfo)
       throw std::runtime_error("Subclass differentiator defined on unknown class");
 
     if (classInfo->subclass_differentiator.offset != SIZE_MAX)
       throw std::runtime_error("More than one subclass differentiator defined for class " + classInfo->name);
 
     DifferentiatorInfo differentiatorInfo;
     differentiatorInfo.offset = offset;
     differentiatorInfo.mapping = mapping;
     classInfo->subclass_differentiator = differentiatorInfo;
-  }
-
-  NamespaceInfo* find_namespace(const char* namespaceName)
-  {
-    for (auto& namespaceInfo : namespaces)
-      if (namespaceInfo.name == namespaceName)
-        return &namespaceInfo;
-    return nullptr;
-  }
-
-  void register_namespace(const char* name)
-  {
-    if (find_namespace(name))
-      throw std::runtime_error(std::string("Duplicate definition for namespace ") + name);
-
-    NamespaceInfo namespaceInfo;
-    namespaceInfo.name = name;
-    namespaces.push_back(namespaceInfo);
-  }
-
-  void register_namespace_property(const char* namespaceName, const char* name,
-      const FunctionInfo& getter, const FunctionInfo& setter)
-  {
-    NamespaceInfo* namespaceInfo = find_namespace(namespaceName);
-    if (!namespaceInfo)
-      throw std::runtime_error(std::string("Property defined on unknown namespace: ") + name);
-
-    PropertyInfo propertyInfo;
-    propertyInfo.name = name;
-    propertyInfo.getter = getter;
-    propertyInfo.setter = setter;
-    namespaceInfo->properties.push_back(propertyInfo);
-  }
-
-  void register_namespace_method(const char* namespaceName, const char* name,
-      const FunctionInfo& call)
-  {
-    NamespaceInfo* namespaceInfo = find_namespace(namespaceName);
-    if (!namespaceInfo)
-      throw std::runtime_error(std::string("Method defined on unknown namespace: ") + name);
-
-    MethodInfo methodInfo;
-    methodInfo.name = name;
-    methodInfo.call = call;
-    namespaceInfo->methods.push_back(methodInfo);
   }
 
   std::string generateCall(const FunctionInfo& call,
       std::vector<std::string>& params)
   {
     if (call.returnType == TypeCategory::DEPENDENT_STRING ||
         call.returnType == TypeCategory::OWNED_STRING)
     {
       params.insert(params.begin(), "string");
     }
@@ skipping 14 matching lines @@
         return "  " + call_str + ";\n";
       case TypeCategory::INT:
       case TypeCategory::FLOAT:
       case TypeCategory::DOUBLE:
         return "  var result = " + call_str + ";\n";
       case TypeCategory::INT64:
         return "  var result = Runtime.makeBigInt(" + call_str + ", " +
                                                   "Runtime.getTempRet0(), " +
                                                   "true);\n";
       case TypeCategory::DEPENDENT_STRING:
-      case TypeCategory::OWNED_STRING:
       {
         std::string result;
         result += "  var string = createString();\n";
         result += "  " + call_str + ";\n";
         result += "  var result = readString(string);\n";
-        if (call.returnType == TypeCategory::OWNED_STRING)
-          result += "  Module._DestroyString(string);\n";
+        // We don't call a destructor here because we know that dependent
+        // strings don't need to clean up.
+        return result;
+      }
+      case TypeCategory::OWNED_STRING:
+      {
+        std::string result;
+        result += "  var string = createOwnedString();\n";
+        result += "  " + call_str + ";\n";
+        result += "  var result = readString(string);\n";
+        result += "  Module._DestroyString(string);\n";
         return result;
       }
       case TypeCategory::STRING_REF:
         return "  var result = readString(" + call_str + ");\n";
       case TypeCategory::CLASS_PTR:
       {
         std::string result;
         result += "  var result = " + call_str + ";\n";
         result += "  if (result)\n";
-        result += "  {\n";
 
         const ClassInfo* cls = find_class(call.pointerType);
         if (!cls)
-          throw std::runtime_error("Function " + std::string(call.name) + " returns pointer to unknown class");
+          throw std::runtime_error("Function " + call.name + " returns pointer to unknown class");
 
         auto offset = cls->subclass_differentiator.offset;
         if (offset == SIZE_MAX)
           result += "    result = exports." + cls->name + "(result);\n";
         else
           result += "    result = exports." + cls->name + ".fromPointer(result);\n";
 
-        result += "  }\n";
         result += "  else\n";
         result += "    result = null;\n";
         return result;
       }
       default:
-        throw std::runtime_error("Unexpected return type for " + std::string(call.name));
-    }
-  }
-
-  std::string wrapCall(const FunctionInfo& call, bool isFunction)
+        throw std::runtime_error("Unexpected return type for " + call.name);
+    }
+  }
+
+  std::string wrapCall(const FunctionInfo& call, bool isFunction,
+      const FunctionInfo& instanceGetter)
   {
     bool hasStringArgs = false;
     std::vector<std::string> params;
     std::string prefix;
 
     if (isFunction)
       prefix += "function";
     prefix += "(";
     for (int i = 0; i < call.args.size(); i++)
     {
@@ skipping 25 matching lines @@
       suffix = "  return result;\n" + suffix;
 
     if (call.returnType == TypeCategory::DEPENDENT_STRING ||
         call.returnType == TypeCategory::OWNED_STRING || hasStringArgs)
     {
       prefix += "  var sp = Runtime.stackSave();\n";
       suffix = "  Runtime.stackRestore(sp);\n" + suffix;
     }
 
     if (call.instance_function)
-      params.insert(params.begin(), "this._pointer");
+    {
+      if (instanceGetter.empty())
+        params.insert(params.begin(), "this._pointer");
+      else
+        params.insert(params.begin(), instanceGetter.name + "()");
+    }
 
     return prefix + generateCall(call, params) + suffix;
   }
 
   void printHelpers()
   {
     printf("var sizeofString = %i;\n", sizeof(String));
 
     puts(R"(
       function copyString(str, buffer)
       {
         var length = str.length;
         for (var i = 0, pointer = (buffer >> 1); i < length; i++, pointer++)
           HEAP16[pointer] = str.charCodeAt(i);
         return length;
       }
 
       function createString(str)
       {
         var length = 0;
         var buffer = 0;
         if (str)
         {
           buffer = Runtime.stackAlloc(str.length * 2);
           length = copyString(str, buffer);
         }
 
         var result = Runtime.stackAlloc(sizeofString);
         Module._InitString(result, buffer, length);
+        return result;
+      }
+
+      function createOwnedString()
+      {
+        var result = Runtime.stackAlloc(sizeofString);
+        Module._InitOwnedString(result);
         return result;
       }
 
       function readString(str)
       {
         var length = Module._GetStringLength(str);
         var pointer = Module._GetStringData(str) >> 1;
         return String.fromCharCode.apply(String, HEAP16.slice(pointer, pointer + length));
       }
 
@@ skipping 10 matching lines @@
           Module._ReleaseRef(this._pointer + ref_counted_offset);
         };
         return result;
       }
     )");
   }
 
   void printClass(const ClassInfo& cls)
   {
     // Begin class definition
-    ClassInfo* baseClass = find_class(cls.baseClass);
-    printf("exports.%s = createClass(%s, %i, {\n", cls.name.c_str(),
-        (baseClass ? ("exports." + baseClass->name).c_str() : "null"),
-        cls.ref_counted_offset);
+    bool singleton = !cls.instanceGetter.empty();
+    if (singleton)
+      printf("exports.%s = {\n", cls.name.c_str());
+    else
+    {
+      ClassInfo* baseClass = find_class(cls.baseClass);
+      printf("exports.%s = createClass(%s, %i, {\n", cls.name.c_str(),
+          (baseClass ? ("exports." + baseClass->name).c_str() : "null"),
+          cls.ref_counted_offset);
+    }
 
     // Print prototype members
-    printProperties(cls.properties);
-    printMethods(cls.methods);
+    for (const auto& property : cls.properties)
+    {
+      if (property.jsValue.empty())
+      {
+        printf("get %s%s,\n", property.name.c_str(),
+               wrapCall(property.getter, false, cls.instanceGetter).c_str());
+        if (!property.setter.empty())
+        {
+          printf("set %s%s,\n", property.name.c_str(),
+                 wrapCall(property.setter, false, cls.instanceGetter).c_str());
+        }
+      }
+      else
+        printf("%s: %s,\n", property.name.c_str(), property.jsValue.c_str());
+    }
+
+    for (const auto& method : cls.methods)
+    {
+      if (method.call.instance_function)
+      {
+        printf("%s: %s,\n",
+            method.name.c_str(),
+            wrapCall(method.call, true, cls.instanceGetter).c_str());
+      }
+    }
 
     // End class definition
-    printf("});\n");
+    if (singleton)
+      printf("};\n");
+    else
+      printf("});\n");
 
     // Print static members
     DifferentiatorInfo differentiator = cls.subclass_differentiator;
     if (differentiator.offset != SIZE_MAX)
     {
-      printf("var %s_mapping = \n", cls.name.c_str());
-      puts("{");
-      for (const auto& item : differentiator.mapping)
-        printf("  %i: '%s',\n", item.first, item.second.c_str());
-      puts("};");
-
       printf("exports.%s.fromPointer = function(ptr)\n", cls.name.c_str());
       puts("{");
       printf("  var type = HEAP32[ptr + %i >> 2];\n", differentiator.offset);
       printf("  if (type in %s_mapping)\n", cls.name.c_str());
-      printf("    return new (exports[%s_mapping[type]])(ptr);\n", cls.name.c_str());
+      printf("    return new %s_mapping[type](ptr);\n", cls.name.c_str());
       printf("  throw new Error('Unexpected %s type: ' + type);\n", cls.name.c_str());
       puts("};");
     }
     else
     {
       printf("exports.%s.fromPointer = function(ptr)\n", cls.name.c_str());
       puts("{");
       printf("  return new exports.%s(ptr);\n", cls.name.c_str());
       puts("};");
     }
 
     for (const auto& method : cls.methods)
     {
       if (!method.call.instance_function)
       {
         printf("exports.%s.%s = %s;\n", cls.name.c_str(), method.name.c_str(),
                wrapCall(method.call).c_str());
       }
     }
   }
 
-  void printNamespace(const NamespaceInfo& namespaceInfo)
-  {
-    printf("exports.%s = {\n", namespaceInfo.name.c_str());
-    printProperties(namespaceInfo.properties);
-    printMethods(namespaceInfo.methods, false);
-    puts("};");
+  void printClassMapping(const ClassInfo& cls)
+  {
+      DifferentiatorInfo differentiator = cls.subclass_differentiator;
+      if (differentiator.offset == SIZE_MAX)
+        return;
+
+      printf("var %s_mapping = \n", cls.name.c_str());
+      puts("{");
+      for (const auto& item : differentiator.mapping)
+        printf("  %i: exports.%s,\n", item.first, item.second.c_str());
+      puts("};");
   }
 }
 
 void printBindings()
 {
   bindings_internal::printHelpers();
 
-  for (const auto& item : classes)
-    bindings_internal::printClass(item);
-  for (const auto& item : namespaces)
-    bindings_internal::printNamespace(item);
+  for (const auto& cls : classes)
+    bindings_internal::printClass(cls);
+  for (const auto& cls : classes)
+    bindings_internal::printClassMapping(cls);
 }