172a454cd3513ac24fbdd0e0cb9ad70b86a99b801Kristian Monsen// Copyright (c) 2011 The Chromium Authors. All rights reserved. 2c407dc5cd9bdc5668497f21b26b09d988ab439deBen Murdoch// Use of this source code is governed by a BSD-style license that can be 3c407dc5cd9bdc5668497f21b26b09d988ab439deBen Murdoch// found in the LICENSE file. 4c407dc5cd9bdc5668497f21b26b09d988ab439deBen Murdoch 5c407dc5cd9bdc5668497f21b26b09d988ab439deBen Murdoch/* 6c407dc5cd9bdc5668497f21b26b09d988ab439deBen Murdoch This file contains the declaration for CppVariant, a type used by C++ classes 7c407dc5cd9bdc5668497f21b26b09d988ab439deBen Murdoch that are to be bound to JavaScript objects. 8c407dc5cd9bdc5668497f21b26b09d988ab439deBen Murdoch 9c407dc5cd9bdc5668497f21b26b09d988ab439deBen Murdoch CppVariant exists primarily as an interface between C++ callers and the 10c407dc5cd9bdc5668497f21b26b09d988ab439deBen Murdoch corresponding NPVariant type. CppVariant also provides a number of 11c407dc5cd9bdc5668497f21b26b09d988ab439deBen Murdoch convenience constructors and accessors, so that the NPVariantType values 12c407dc5cd9bdc5668497f21b26b09d988ab439deBen Murdoch don't need to be exposed, and a destructor to free any memory allocated for 13c407dc5cd9bdc5668497f21b26b09d988ab439deBen Murdoch string values. 14c407dc5cd9bdc5668497f21b26b09d988ab439deBen Murdoch 15c407dc5cd9bdc5668497f21b26b09d988ab439deBen Murdoch For a usage example, see cpp_binding_example.{h|cc}. 16c407dc5cd9bdc5668497f21b26b09d988ab439deBen Murdoch*/ 17c407dc5cd9bdc5668497f21b26b09d988ab439deBen Murdoch 18c407dc5cd9bdc5668497f21b26b09d988ab439deBen Murdoch#ifndef WEBKIT_GLUE_CPP_VARIANT_H__ 19c407dc5cd9bdc5668497f21b26b09d988ab439deBen Murdoch#define WEBKIT_GLUE_CPP_VARIANT_H__ 20c407dc5cd9bdc5668497f21b26b09d988ab439deBen Murdoch 21c407dc5cd9bdc5668497f21b26b09d988ab439deBen Murdoch#include <string> 22c407dc5cd9bdc5668497f21b26b09d988ab439deBen Murdoch#include <vector> 23c407dc5cd9bdc5668497f21b26b09d988ab439deBen Murdoch 24c407dc5cd9bdc5668497f21b26b09d988ab439deBen Murdoch#include "base/basictypes.h" 25c407dc5cd9bdc5668497f21b26b09d988ab439deBen Murdoch#include "third_party/npapi/bindings/npruntime.h" 26c407dc5cd9bdc5668497f21b26b09d988ab439deBen Murdoch 27c407dc5cd9bdc5668497f21b26b09d988ab439deBen Murdochclass CppVariant : public NPVariant { 28c407dc5cd9bdc5668497f21b26b09d988ab439deBen Murdoch public: 29c407dc5cd9bdc5668497f21b26b09d988ab439deBen Murdoch CppVariant(); 30c407dc5cd9bdc5668497f21b26b09d988ab439deBen Murdoch ~CppVariant(); 31c407dc5cd9bdc5668497f21b26b09d988ab439deBen Murdoch void SetNull(); 32c407dc5cd9bdc5668497f21b26b09d988ab439deBen Murdoch void Set(bool value); 33c407dc5cd9bdc5668497f21b26b09d988ab439deBen Murdoch void Set(int32_t value); 34c407dc5cd9bdc5668497f21b26b09d988ab439deBen Murdoch void Set(double value); 35c407dc5cd9bdc5668497f21b26b09d988ab439deBen Murdoch 36c407dc5cd9bdc5668497f21b26b09d988ab439deBen Murdoch // Note that setting a CppVariant to a string value involves copying the 37c407dc5cd9bdc5668497f21b26b09d988ab439deBen Murdoch // string data, which must be freed with a call to FreeData() when the 38c407dc5cd9bdc5668497f21b26b09d988ab439deBen Murdoch // CppVariant is set to a different value or is no longer needed. Normally 39c407dc5cd9bdc5668497f21b26b09d988ab439deBen Murdoch // this is handled by the other Set() methods and by the destructor. 40c407dc5cd9bdc5668497f21b26b09d988ab439deBen Murdoch void Set(const char* value); // Must be a null-terminated string. 41c407dc5cd9bdc5668497f21b26b09d988ab439deBen Murdoch void Set(const std::string& value); 42c407dc5cd9bdc5668497f21b26b09d988ab439deBen Murdoch void Set(const NPString& new_value); 43c407dc5cd9bdc5668497f21b26b09d988ab439deBen Murdoch void Set(const NPVariant& new_value); 44c407dc5cd9bdc5668497f21b26b09d988ab439deBen Murdoch 45c407dc5cd9bdc5668497f21b26b09d988ab439deBen Murdoch // Note that setting a CppVariant to an NPObject involves ref-counting 46c407dc5cd9bdc5668497f21b26b09d988ab439deBen Murdoch // the actual object. FreeData() should only be called if the CppVariant 47c407dc5cd9bdc5668497f21b26b09d988ab439deBen Murdoch // is no longer needed. The other Set() methods handle this internally. 48c407dc5cd9bdc5668497f21b26b09d988ab439deBen Murdoch // Also, the object's NPClass is expected to be a static object: neither 49c407dc5cd9bdc5668497f21b26b09d988ab439deBen Murdoch // the NP runtime nor CPPVariant will ever free it. 50c407dc5cd9bdc5668497f21b26b09d988ab439deBen Murdoch void Set(NPObject* new_value); 51c407dc5cd9bdc5668497f21b26b09d988ab439deBen Murdoch 52c407dc5cd9bdc5668497f21b26b09d988ab439deBen Murdoch // These three methods all perform deep copies of any string data. This 53c407dc5cd9bdc5668497f21b26b09d988ab439deBen Murdoch // allows local CppVariants to be released by the destructor without 54c407dc5cd9bdc5668497f21b26b09d988ab439deBen Murdoch // corrupting their sources. In performance-critical code, or when strings 55c407dc5cd9bdc5668497f21b26b09d988ab439deBen Murdoch // are very long, avoid creating new CppVariants. 56c407dc5cd9bdc5668497f21b26b09d988ab439deBen Murdoch // In case of NPObject as the data, the copying involves ref-counting 57c407dc5cd9bdc5668497f21b26b09d988ab439deBen Murdoch // as opposed to deep-copying. The ref-counting ensures that sources don't 58c407dc5cd9bdc5668497f21b26b09d988ab439deBen Murdoch // get corrupted when the copies get destroyed. 59c407dc5cd9bdc5668497f21b26b09d988ab439deBen Murdoch void CopyToNPVariant(NPVariant* result) const; 60c407dc5cd9bdc5668497f21b26b09d988ab439deBen Murdoch CppVariant& operator=(const CppVariant& original); 61c407dc5cd9bdc5668497f21b26b09d988ab439deBen Murdoch CppVariant(const CppVariant& original); 62c407dc5cd9bdc5668497f21b26b09d988ab439deBen Murdoch 63c407dc5cd9bdc5668497f21b26b09d988ab439deBen Murdoch // Calls NPN_ReleaseVariantValue, which frees any string data 64c407dc5cd9bdc5668497f21b26b09d988ab439deBen Murdoch // held by the object and sets its type to null. 65c407dc5cd9bdc5668497f21b26b09d988ab439deBen Murdoch // In case of NPObject, the NPN_ReleaseVariantValue decrements 66c407dc5cd9bdc5668497f21b26b09d988ab439deBen Murdoch // the ref-count (releases when ref-count becomes 0) 67c407dc5cd9bdc5668497f21b26b09d988ab439deBen Murdoch void FreeData(); 68c407dc5cd9bdc5668497f21b26b09d988ab439deBen Murdoch 69c407dc5cd9bdc5668497f21b26b09d988ab439deBen Murdoch // Compares this CppVariant's type and value to another's. They must be 70c407dc5cd9bdc5668497f21b26b09d988ab439deBen Murdoch // identical in both type and value to be considered equal. For string and 71c407dc5cd9bdc5668497f21b26b09d988ab439deBen Murdoch // object types, a deep comparison is performed; that is, the contents of the 72c407dc5cd9bdc5668497f21b26b09d988ab439deBen Murdoch // strings, or the classes and refcounts of the objects, must be the same, 73c407dc5cd9bdc5668497f21b26b09d988ab439deBen Murdoch // but they need not be the same pointers. 74c407dc5cd9bdc5668497f21b26b09d988ab439deBen Murdoch bool isEqual(const CppVariant& other) const; 75c407dc5cd9bdc5668497f21b26b09d988ab439deBen Murdoch 76c407dc5cd9bdc5668497f21b26b09d988ab439deBen Murdoch // The value of a CppVariant may be read directly from its NPVariant (but 77c407dc5cd9bdc5668497f21b26b09d988ab439deBen Murdoch // should only be set using one of the Set() methods above). Although the 78c407dc5cd9bdc5668497f21b26b09d988ab439deBen Murdoch // type of a CppVariant is likewise public, it can be accessed through these 79c407dc5cd9bdc5668497f21b26b09d988ab439deBen Murdoch // functions rather than directly if a caller wishes to avoid dependence on 80c407dc5cd9bdc5668497f21b26b09d988ab439deBen Murdoch // the NPVariantType values. 81c407dc5cd9bdc5668497f21b26b09d988ab439deBen Murdoch bool isBool() const { return (type == NPVariantType_Bool); } 82c407dc5cd9bdc5668497f21b26b09d988ab439deBen Murdoch bool isInt32() const { return (type == NPVariantType_Int32); } 83c407dc5cd9bdc5668497f21b26b09d988ab439deBen Murdoch bool isDouble() const { return (type == NPVariantType_Double); } 84c407dc5cd9bdc5668497f21b26b09d988ab439deBen Murdoch bool isNumber() const { return (isInt32() || isDouble()); } 85c407dc5cd9bdc5668497f21b26b09d988ab439deBen Murdoch bool isString() const { return (type == NPVariantType_String); } 86c407dc5cd9bdc5668497f21b26b09d988ab439deBen Murdoch bool isVoid() const { return (type == NPVariantType_Void); } 87c407dc5cd9bdc5668497f21b26b09d988ab439deBen Murdoch bool isNull() const { return (type == NPVariantType_Null); } 88c407dc5cd9bdc5668497f21b26b09d988ab439deBen Murdoch bool isEmpty() const { return (isVoid() || isNull()); } 89c407dc5cd9bdc5668497f21b26b09d988ab439deBen Murdoch bool isObject() const { return (type == NPVariantType_Object); } 90c407dc5cd9bdc5668497f21b26b09d988ab439deBen Murdoch 91c407dc5cd9bdc5668497f21b26b09d988ab439deBen Murdoch // Converters. The CppVariant must be of a type convertible to these values. 9272a454cd3513ac24fbdd0e0cb9ad70b86a99b801Kristian Monsen // For example, ToInt32() works only if isNumber() is true. 93c407dc5cd9bdc5668497f21b26b09d988ab439deBen Murdoch std::string ToString() const; 94c407dc5cd9bdc5668497f21b26b09d988ab439deBen Murdoch int32_t ToInt32() const; 95c407dc5cd9bdc5668497f21b26b09d988ab439deBen Murdoch double ToDouble() const; 96c407dc5cd9bdc5668497f21b26b09d988ab439deBen Murdoch bool ToBoolean() const; 9772a454cd3513ac24fbdd0e0cb9ad70b86a99b801Kristian Monsen // Returns a vector of CppVariant for the specified variant. This should only 9872a454cd3513ac24fbdd0e0cb9ad70b86a99b801Kristian Monsen // be called on an Object. If the object has no "length" property an empty 9972a454cd3513ac24fbdd0e0cb9ad70b86a99b801Kristian Monsen // vector is returned. 10072a454cd3513ac24fbdd0e0cb9ad70b86a99b801Kristian Monsen std::vector<CppVariant> ToVector() const; 101c407dc5cd9bdc5668497f21b26b09d988ab439deBen Murdoch 102c407dc5cd9bdc5668497f21b26b09d988ab439deBen Murdoch // Invoke method of the given name on an object with the supplied arguments. 103c407dc5cd9bdc5668497f21b26b09d988ab439deBen Murdoch // The first argument should be the object on which the method is to be 104c407dc5cd9bdc5668497f21b26b09d988ab439deBen Murdoch // invoked. Returns whether the method was successfully invoked. If the 105c407dc5cd9bdc5668497f21b26b09d988ab439deBen Murdoch // method was invoked successfully, any return value is stored in the 106c407dc5cd9bdc5668497f21b26b09d988ab439deBen Murdoch // CppVariant specified by result. 107c407dc5cd9bdc5668497f21b26b09d988ab439deBen Murdoch bool Invoke(const std::string& method, const CppVariant* args, 108c407dc5cd9bdc5668497f21b26b09d988ab439deBen Murdoch uint32 arg_count, CppVariant& result) const; 109c407dc5cd9bdc5668497f21b26b09d988ab439deBen Murdoch}; 110c407dc5cd9bdc5668497f21b26b09d988ab439deBen Murdoch 111c407dc5cd9bdc5668497f21b26b09d988ab439deBen Murdoch#endif // WEBKIT_GLUE_CPP_VARIANT_H__ 112