[fix] More robust type information for base class type checking.

4 files changed, 95 insertions, 36 deletions

diff --git a/xbmc/interfaces/python/PythonSwig.cpp.template b/xbmc/interfaces/python/PythonSwig.cpp.template
index 4f38c8ef69..2a7997354a 100644
--- a/xbmc/interfaces/python/PythonSwig.cpp.template
+++ b/xbmc/interfaces/python/PythonSwig.cpp.template
@@ -60,7 +60,7 @@ Helper.setup(classes,
       (Pattern.compile('''(p.){0,1}std::vector<\\(.*\\)>''')) : new File('typemaps/python.vector.outtm'),
       (Pattern.compile('''(p.){0,1}Tuple<\\(.*\\)>''')) : new File('typemaps/python.Tuple.outtm'),
       (Pattern.compile('''(p.){0,1}Alternative<\\(.*\\)>''')) : new File('typemaps/python.Alternative.outtm')
-    ], '${result} = makePythonInstance(${api},&Py${Helper.findFullClassName(classnode).replaceAll(\'::\',\'_\')}_Type,"${type}",true);',
+    ], '${result} = makePythonInstance(${api},&Py${Helper.findFullClassName(classnode).replaceAll(\'::\',\'_\')}_Type,&Ty${Helper.findFullClassName(classnode).replaceAll(\'::\',\'_\')}_Type,true);',
     /**
      * This is meant to contain mini-templates for converting the parameter types
      * of the native call to be converted from the python types provided by the caller.
@@ -208,7 +208,7 @@ void doMethod(method, MethodType methodType)
     // transform the result
 <%
     if (constructor) {
-      %>    result = makePythonInstance(apiResult,pytype,"${returns}",false);<%
+      %>    result = makePythonInstance(apiResult,pytype,&Ty${SwigTypeParser.getRootType(returns).replaceAll('::','_')}_Type,false);<%
     }
     else { 
 %>    ${Helper.getOutConversion(returns,'result',method)}<%
@@ -235,8 +235,16 @@ void doClassTypeInfo(Node clazz, List classNameAsVariables = null)
   classNameAsVariables?.add(classNameAsVariable)
 %>
   //=========================================================================
-  // This variable will hold the Python Type information for ${fullClassName}
+  // These variables will hold the Python Type information for ${fullClassName}
   PyTypeObject Py${classNameAsVariable}_Type;
+  TypeInfo Ty${classNameAsVariable}_Type;<%
+
+    Node baseclass = PythonTools.findValidBaseClass(clazz, module)
+    if (baseclass)
+    {%>
+  TypeConverter<${Helper.findFullClassName(baseclass)},${fullClassName}> ${classNameAsVariable}_ParentConverter;<%
+    }
+%>
   //=========================================================================
 <%    
 }
@@ -282,34 +290,25 @@ void doClassMethodInfo(Node clazz, List initTypeCalls = null)
                  ${PythonTools.makeDocString(clazz.doc[0])}
                 );
 <%  } %>
-    PyXBMCInitializeTypeObject(&Py${classNameAsVariable}_Type);
+    PyXBMCInitializeTypeObject(&Py${classNameAsVariable}_Type,&Ty${classNameAsVariable}_Type);
 
     Py${classNameAsVariable}_Type.tp_name = (char*)"${module.@name}.${clazz.@sym_name}";
     Py${classNameAsVariable}_Type.tp_basicsize = sizeof(PyHolder);
     Py${classNameAsVariable}_Type.tp_dealloc = (destructor)${module.@name}_${classNameAsVariable}_Dealloc;
     Py${classNameAsVariable}_Type.tp_flags = Py_TPFLAGS_DEFAULT | Py_TPFLAGS_BASETYPE;
     Py${classNameAsVariable}_Type.tp_doc = ${Helper.hasDoc(clazz) ? (classNameAsVariable + '__doc__') : 'NULL' };
-    Py${classNameAsVariable}_Type.tp_methods = ${classNameAsVariable}_methods; <%
-    // I need to find the base type if there is a known class with it
-    assert clazz.baselist.size() < 2, "${clazz} has multiple baselists - need to write code to separate out the public one."
-    String baseclass = 'NULL'
-    List knownbases = []
-    if (clazz.baselist)
-    { 
-      if (clazz.baselist[0].base) clazz.baselist[0].base.each {
-          Node baseclassnode = Helper.findClassNodeByName(module,it.@name,clazz)
-          if (baseclassnode) knownbases.add(baseclassnode)
-          else if (!Helper.isKnownBaseType(it.@name,clazz))
-            System.out.println("WARNING: the base class ${it.@name} for ${fullClassName} is unrecognized within ${module.@name}.")
-        }
-    }
-    assert knownbases.size() < 2, 
-           "The class ${fullClassName} has too many known base classes. Multiple inheritance isn't supported in the code generator. Please \"#ifdef SWIG\" out all but one."
-    if (knownbases.size() > 0)
-      baseclass = "&Py${PythonTools.getClassNameAsVariable(knownbases[0])}_Type"
-%>
-    Py${classNameAsVariable}_Type.tp_base = ${baseclass};
+    Py${classNameAsVariable}_Type.tp_methods = ${classNameAsVariable}_methods;
+<%
+    Node baseclass = PythonTools.findValidBaseClass(clazz, module)
+
+%>    Py${classNameAsVariable}_Type.tp_base = ${baseclass ? ('&Py' + PythonTools.getClassNameAsVariable(baseclass) + '_Type') : "NULL"};
     Py${classNameAsVariable}_Type.tp_new = <% Helper.hasHiddenConstructor(clazz) ? print('NULL') : print("${module.@name}_${classNameAsVariable}_New") %>;
+
+    Ty${classNameAsVariable}_Type.swigType="p.${fullClassName}";<%
+  if (baseclass) { %>
+    Ty${classNameAsVariable}_Type.parentType=&Ty${PythonTools.getClassNameAsVariable(baseclass)}_Type;
+    Ty${classNameAsVariable}_Type.converter=&${classNameAsVariable}_ParentConverter;
+<%} %>  
   }
   //=========================================================================
 <%
diff --git a/xbmc/interfaces/python/PythonTools.groovy b/xbmc/interfaces/python/PythonTools.groovy
index 3f1c0d4a1d..cc8c611247 100644
--- a/xbmc/interfaces/python/PythonTools.groovy
+++ b/xbmc/interfaces/python/PythonTools.groovy
@@ -116,4 +116,24 @@ public class PythonTools
 
     return ret
   }
+
+  public static Node findValidBaseClass(Node clazz, Node module, boolean warn = false)
+  {
+    // I need to find the base type if there is a known class with it
+    assert clazz.baselist.size() < 2, "${clazz} has multiple baselists - need to write code to separate out the public one."
+    String baseclass = 'NULL'
+    List knownbases = []
+    if (clazz.baselist)
+    { 
+      if (clazz.baselist[0].base) clazz.baselist[0].base.each {
+          Node baseclassnode = Helper.findClassNodeByName(module,it.@name,clazz)
+          if (baseclassnode) knownbases.add(baseclassnode)
+          else if (warn && !Helper.isKnownBaseType(it.@name,clazz))
+            System.out.println("WARNING: the base class ${it.@name} for ${Helper.findFullClassName(clazz)} is unrecognized within ${module.@name}.")
+        }
+    }
+    assert knownbases.size() < 2, 
+      "The class ${Helper.findFullClassName(clazz)} has too many known base classes. Multiple inheritance isn't supported in the code generator. Please \"#ifdef SWIG\" out all but one."
+    return knownbases.size() > 0 ? knownbases[0] : null
+  }
 }
diff --git a/xbmc/interfaces/python/swig.cpp b/xbmc/interfaces/python/swig.cpp
index a927d1f53c..42838c2821 100644
--- a/xbmc/interfaces/python/swig.cpp
+++ b/xbmc/interfaces/python/swig.cpp
@@ -24,12 +24,13 @@
 
 namespace PythonBindings
 {
-  void PyXBMCInitializeTypeObject(PyTypeObject* type_object)
+  void PyXBMCInitializeTypeObject(PyTypeObject* type_object, TypeInfo* typeInfo)
   {
     static PyTypeObject py_type_object_header = { PyObject_HEAD_INIT(NULL) 0};
     int size = (long*)&(py_type_object_header.tp_name) - (long*)&py_type_object_header;
     memset(type_object, 0, sizeof(PyTypeObject));
     memcpy(type_object, &py_type_object_header, size);
+    memset(typeInfo, 0, sizeof(TypeInfo));
   }
 
   int PyXBMCGetUnicodeString(std::string& buf, PyObject* pObject, bool coerceToString,
@@ -173,5 +174,24 @@ namespace PythonBindings
 
     SetMessage("%s",msg.c_str());
   }
+
+  void* doretrieveApiInstance(const PyHolder* pythonType, const TypeInfo* typeInfo, const char* swigType, 
+                              const char* methodNamespacePrefix, const char* methodNameForErrorString) throw (WrongTypeException)
+  {
+    if (pythonType == NULL || pythonType->magicNumber != XBMC_PYTHON_TYPE_MAGIC_NUMBER)
+      throw WrongTypeException("Non api type passed in place of the expected type \"%s.\"",swigType);
+    if (!isParameterRightType(typeInfo->swigType,swigType,methodNamespacePrefix))
+    {
+      // maybe it's a child class
+      if (typeInfo->parentType)
+        return doretrieveApiInstance(pythonType, typeInfo->parentType,swigType, 
+                                     methodNamespacePrefix, methodNameForErrorString);
+      else
+        throw WrongTypeException("Incorrect type passed to \"%s\", was expecting a \"%s\" but received a \"%s\"",
+                                 methodNameForErrorString,swigType,typeInfo->swigType);
+    }
+    return ((PyHolder*)pythonType)->pSelf;
+  }
+
 }
 
diff --git a/xbmc/interfaces/python/swig.h b/xbmc/interfaces/python/swig.h
index ca76d01737..06080ffa34 100644
--- a/xbmc/interfaces/python/swig.h
+++ b/xbmc/interfaces/python/swig.h
@@ -30,17 +30,37 @@
 
 namespace PythonBindings
 {
-  void PyXBMCInitializeTypeObject(PyTypeObject* type_object);
   int PyXBMCGetUnicodeString(std::string& buf, PyObject* pObject, bool coerceToString = false,
                              const char* pos = "unknown", 
                              const char* methodname = "unknown");
 
+  // This is for casting from child class to base class
+  struct TypeConverterBase
+  {
+    virtual void* convert(void* from) = 0;
+  };
+
+  /**
+   * Template to allow the instantiation of a particular type conversion
+   */
+  template<class T, class F> struct TypeConverter : public TypeConverterBase
+  {
+    inline virtual void* convert(void* from) { return static_cast<T*>((F*)from); }
+  };
+
+  struct TypeInfo
+  {
+    const char* swigType;
+    TypeInfo* parentType;
+    TypeConverterBase* converter;
+  };
+
   // This will hold the pointer to the api type, whether known or unknown
   struct PyHolder
   { 
     PyObject_HEAD
     int32_t magicNumber;
-    const char* swigType;
+    const TypeInfo* typeInfo;
     void* pSelf;
   };
 
@@ -48,6 +68,8 @@ namespace PythonBindings
 
 #define XBMC_PYTHON_TYPE_MAGIC_NUMBER 0x58626D63
 
+  void PyXBMCInitializeTypeObject(PyTypeObject* type_object, TypeInfo* typeInfo);
+
   /**
    * This method retrieves the pointer from the PyHolder. The return value should
    * be case to the appropriate type.
@@ -67,21 +89,19 @@ namespace PythonBindings
 
   bool isParameterRightType(const char* passedType, const char* expectedType, const char* methodNamespacePrefix);
 
+  void* doretrieveApiInstance(const PyHolder* pythonType, const TypeInfo* typeInfo, const char* swigType, 
+                              const char* methodNamespacePrefix, const char* methodNameForErrorString) throw (WrongTypeException);
+
   /**
    * This method retrieves the pointer from the PyHolder. The return value should
    * be case to the appropriate type.
    *
    * Since the calls to this are generated there's no NULL pointer checks
    */
-  inline void* retrieveApiInstance(PyObject* pythonType, const char* swigType, const char* methodNamespacePrefix,
+  inline void* retrieveApiInstance(const PyObject* pythonType, const char* swigType, const char* methodNamespacePrefix,
                                    const char* methodNameForErrorString) throw (WrongTypeException)
   {
-    if (pythonType == NULL || ((PyHolder*)pythonType)->magicNumber != XBMC_PYTHON_TYPE_MAGIC_NUMBER)
-      throw WrongTypeException("Non api type passed in place of the expected type \"%s.\"",swigType);
-    if (!isParameterRightType(((PyHolder*)pythonType)->swigType,swigType,methodNamespacePrefix))
-      throw WrongTypeException("Incorrect type passed to \"%s\", was expecting a \"%s\" but received a \"%s\"",
-                               methodNameForErrorString,swigType,((PyHolder*)pythonType)->swigType);
-    return ((PyHolder*)pythonType)->pSelf;
+    return doretrieveApiInstance(((PyHolder*)pythonType),((PyHolder*)pythonType)->typeInfo, swigType, methodNamespacePrefix, methodNameForErrorString);
   }
 
   inline void prepareForReturn(XBMCAddon::AddonClass* c) { if(c) c->Acquire(); }
@@ -94,7 +114,7 @@ namespace PythonBindings
    * NOTE: swigTypeString must be in the data segment. That is, it should be an explicit string since
    * the const char* is stored in a PyHolder struct and never deleted.
    */
-  inline PyObject* makePythonInstance(void* api, PyTypeObject* typeObj, const char* swigTypeString, bool incrementRefCount)
+  inline PyObject* makePythonInstance(void* api, PyTypeObject* typeObj, TypeInfo* typeInfo, bool incrementRefCount)
   {
     // null api types result in Py_None
     if (!api)
@@ -106,7 +126,7 @@ namespace PythonBindings
     PyHolder* self = (PyHolder*)typeObj->tp_alloc(typeObj,0);
     if (!self) return NULL;
     self->magicNumber = XBMC_PYTHON_TYPE_MAGIC_NUMBER;
-    self->swigType = swigTypeString;
+    self->typeInfo = typeInfo;
     self->pSelf = api;
     if (incrementRefCount)
       Py_INCREF((PyObject*)self);