Check in the pristine copy of ICU 4.6...

icu46/source/common/unicode/uobject.h

+/*
+******************************************************************************
+*
+*   Copyright (C) 2002-2010, International Business Machines
+*   Corporation and others.  All Rights Reserved.
+*
+******************************************************************************
+*   file name:  uobject.h
+*   encoding:   US-ASCII
+*   tab size:   8 (not used)
+*   indentation:4
+*
+*   created on: 2002jun26
+*   created by: Markus W. Scherer
+*/
+
+#ifndef __UOBJECT_H__
+#define __UOBJECT_H__
+
+#include "unicode/utypes.h"
+
+U_NAMESPACE_BEGIN
+
+/**
+ * \file
+ * \brief C++ API: Common ICU base class UObject.
+ */
+
+/**  U_OVERRIDE_CXX_ALLOCATION - Define this to override operator new and
+ *                               delete in UMemory. Enabled by default for ICU.
+ *
+ *         Enabling forces all allocation of ICU object types to use ICU's
+ *         memory allocation. On Windows, this allows the ICU DLL to be used by
+ *         applications that statically link the C Runtime library, meaning that
+ *         the app and ICU will be using different heaps.
+ *
+ * @stable ICU 2.2
+ */                              
+#ifndef U_OVERRIDE_CXX_ALLOCATION
+#define U_OVERRIDE_CXX_ALLOCATION 1
+#endif
+
+/** 
+ * \def U_HAVE_PLACEMENT_NEW
+ *  Define this to define the placement new and
+ *                          delete in UMemory for STL.
+ *
+ * @stable ICU 2.6
+ */                              
+#ifndef U_HAVE_PLACEMENT_NEW
+#define U_HAVE_PLACEMENT_NEW 1
+#endif
+
+
+/** 
+ * \def U_HAVE_DEBUG_LOCATION_NEW 
+ * Define this to define the MFC debug
+ * version of the operator new.
+ *
+ * @stable ICU 3.4
+ */                              
+#ifndef U_HAVE_DEBUG_LOCATION_NEW
+#define U_HAVE_DEBUG_LOCATION_NEW 0
+#endif
+
+/**
+ * @{
+ * \def U_NO_THROW
+ *         Define this to define the throw() specification so
+ *                 certain functions do not throw any exceptions
+ *
+ *         UMemory operator new methods should have the throw() specification 
+ *         appended to them, so that the compiler adds the additional NULL check 
+ *         before calling constructors. Without, if <code>operator new</code> returns NULL the 
+ *         constructor is still called, and if the constructor references member 
+ *         data, (which it typically does), the result is a segmentation violation.
+ *
+ * @draft ICU 4.2
+ */                              
+#ifndef U_NO_THROW
+#define U_NO_THROW throw()
+#endif
+
+/** @} */
+
+/**
+ * UMemory is the common ICU base class.
+ * All other ICU C++ classes are derived from UMemory (starting with ICU 2.4).
+ *
+ * This is primarily to make it possible and simple to override the
+ * C++ memory management by adding new/delete operators to this base class.
+ *
+ * To override ALL ICU memory management, including that from plain C code,
+ * replace the allocation functions declared in cmemory.h
+ *
+ * UMemory does not contain any virtual functions.
+ * Common "boilerplate" functions are defined in UObject.
+ *
+ * @stable ICU 2.4
+ */
+class U_COMMON_API UMemory {
+public:
+
+/* test versions for debugging shaper heap memory problems */
+#ifdef SHAPER_MEMORY_DEBUG  
+    static void * NewArray(int size, int count);
+    static void * GrowArray(void * array, int newSize );
+    static void   FreeArray(void * array );
+#endif
+
+#if U_OVERRIDE_CXX_ALLOCATION
+    /**
+     * Override for ICU4C C++ memory management.
+     * simple, non-class types are allocated using the macros in common/cmemory.h
+     * (uprv_malloc(), uprv_free(), uprv_realloc());
+     * they or something else could be used here to implement C++ new/delete
+     * for ICU4C C++ classes
+     * @stable ICU 2.4
+     */
+    static void * U_EXPORT2 operator new(size_t size) U_NO_THROW;
+
+    /**
+     * Override for ICU4C C++ memory management.
+     * See new().
+     * @stable ICU 2.4
+     */
+    static void * U_EXPORT2 operator new[](size_t size) U_NO_THROW;
+
+    /**
+     * Override for ICU4C C++ memory management.
+     * simple, non-class types are allocated using the macros in common/cmemory.h
+     * (uprv_malloc(), uprv_free(), uprv_realloc());
+     * they or something else could be used here to implement C++ new/delete
+     * for ICU4C C++ classes
+     * @stable ICU 2.4
+     */
+    static void U_EXPORT2 operator delete(void *p) U_NO_THROW;
+
+    /**
+     * Override for ICU4C C++ memory management.
+     * See delete().
+     * @stable ICU 2.4
+     */
+    static void U_EXPORT2 operator delete[](void *p) U_NO_THROW;
+
+#if U_HAVE_PLACEMENT_NEW
+    /**
+     * Override for ICU4C C++ memory management for STL.
+     * See new().
+     * @stable ICU 2.6
+     */
+    static inline void * U_EXPORT2 operator new(size_t, void *ptr) U_NO_THROW { return ptr; }
+
+    /**
+     * Override for ICU4C C++ memory management for STL.
+     * See delete().
+     * @stable ICU 2.6
+     */
+    static inline void U_EXPORT2 operator delete(void *, void *) U_NO_THROW {}
+#endif /* U_HAVE_PLACEMENT_NEW */
+#if U_HAVE_DEBUG_LOCATION_NEW
+    /**
+      * This method overrides the MFC debug version of the operator new
+      * 
+      * @param size   The requested memory size
+      * @param file   The file where the allocation was requested
+      * @param line   The line where the allocation was requested 
+      */ 
+    static void * U_EXPORT2 operator new(size_t size, const char* file, int line) U_NO_THROW;
+    /**
+      * This method provides a matching delete for the MFC debug new
+      * 
+      * @param p      The pointer to the allocated memory
+      * @param file   The file where the allocation was requested
+      * @param line   The line where the allocation was requested 
+      */ 
+    static void U_EXPORT2 operator delete(void* p, const char* file, int line) U_NO_THROW;
+#endif /* U_HAVE_DEBUG_LOCATION_NEW */
+#endif /* U_OVERRIDE_CXX_ALLOCATION */
+
+    /*
+     * Assignment operator not declared. The compiler will provide one
+     * which does nothing since this class does not contain any data members.
+     * API/code coverage may show the assignment operator as present and
+     * untested - ignore.
+     * Subclasses need this assignment operator if they use compiler-provided
+     * assignment operators of their own. An alternative to not declaring one
+     * here would be to declare and empty-implement a protected or public one.
+    UMemory &UMemory::operator=(const UMemory &);
+     */
+};
+
+/**
+ * UObject is the common ICU "boilerplate" class.
+ * UObject inherits UMemory (starting with ICU 2.4),
+ * and all other public ICU C++ classes
+ * are derived from UObject (starting with ICU 2.2).
+ *
+ * UObject contains common virtual functions like for ICU's "poor man's RTTI".
+ * It does not contain default implementations of virtual methods
+ * like getDynamicClassID to allow derived classes such as Format
+ * to declare these as pure virtual.
+ *
+ * The clone() function is not available in UObject because it is not
+ * implemented by all ICU classes.
+ * Many ICU services provide a clone() function for their class trees,
+ * defined on the service's C++ base class, and all subclasses within that
+ * service class tree return a pointer to the service base class
+ * (which itself is a subclass of UObject).
+ * This is because some compilers do not support covariant (same-as-this)
+ * return types; cast to the appropriate subclass if necessary.
+ *
+ * @stable ICU 2.2
+ */
+class U_COMMON_API UObject : public UMemory {
+public:
+    /**
+     * Destructor.
+     *
+     * @stable ICU 2.2
+     */
+    virtual ~UObject();
+
+    /**
+     * ICU4C "poor man's RTTI", returns a UClassID for the actual ICU class.
+     *
+     * @stable ICU 2.2
+     */
+    virtual UClassID getDynamicClassID() const = 0;
+
+protected:
+    // the following functions are protected to prevent instantiation and
+    // direct use of UObject itself
+
+    // default constructor
+    // commented out because UObject is abstract (see getDynamicClassID)
+    // inline UObject() {}
+
+    // copy constructor
+    // commented out because UObject is abstract (see getDynamicClassID)
+    // inline UObject(const UObject &other) {}
+
+#if 0
+    // TODO Sometime in the future. Implement operator==().
+    // (This comment inserted in 2.2)
+    // some or all of the following "boilerplate" functions may be made public
+    // in a future ICU4C release when all subclasses implement them
+
+    // assignment operator
+    // (not virtual, see "Taligent's Guide to Designing Programs" pp.73..74)
+    // commented out because the implementation is the same as a compiler's default
+    // UObject &operator=(const UObject &other) { return *this; }
+
+    // comparison operators
+    virtual inline UBool operator==(const UObject &other) const { return this==&other; }
+    inline UBool operator!=(const UObject &other) const { return !operator==(other); }
+
+    // clone() commented out from the base class:
+    // some compilers do not support co-variant return types
+    // (i.e., subclasses would have to return UObject * as well, instead of SubClass *)
+    // see also UObject class documentation.
+    // virtual UObject *clone() const;
+#endif
+
+    /*
+     * Assignment operator not declared. The compiler will provide one
+     * which does nothing since this class does not contain any data members.
+     * API/code coverage may show the assignment operator as present and
+     * untested - ignore.
+     * Subclasses need this assignment operator if they use compiler-provided
+     * assignment operators of their own. An alternative to not declaring one
+     * here would be to declare and empty-implement a protected or public one.
+    UObject &UObject::operator=(const UObject &);
+     */
+
+// Future implementation for RTTI that support subtyping. [alan]
+// 
+//  public:
+//     /**
+//      * @internal
+//      */
+//     static UClassID getStaticClassID();
+// 
+//     /**
+//      * @internal
+//      */
+//     UBool instanceOf(UClassID type) const;
+};
+
+/**
+ * This is a simple macro to add ICU RTTI to an ICU object implementation.
+ * This does not go into the header. This should only be used in *.cpp files.
+ *
+ * @param myClass The name of the class that needs RTTI defined.
+ * @internal
+ */
+#define UOBJECT_DEFINE_RTTI_IMPLEMENTATION(myClass) \
+    UClassID U_EXPORT2 myClass::getStaticClassID() { \
+        static char classID = 0; \
+        return (UClassID)&classID; \
+    } \
+    UClassID myClass::getDynamicClassID() const \
+    { return myClass::getStaticClassID(); }
+
+
+/**
+ * This macro adds ICU RTTI to an ICU abstract class implementation.
+ * This macro should be invoked in *.cpp files.  The corresponding
+ * header should declare getStaticClassID.
+ *
+ * @param myClass The name of the class that needs RTTI defined.
+ * @internal
+ */
+#define UOBJECT_DEFINE_ABSTRACT_RTTI_IMPLEMENTATION(myClass) \
+    UClassID U_EXPORT2 myClass::getStaticClassID() { \
+        static char classID = 0; \
+        return (UClassID)&classID; \
+    }
+
+/**
+ * This is a simple macro to express that a class and its subclasses do not offer
+ * ICU's "poor man's RTTI".
+ * Beginning with ICU 4.6, ICU requires C++ compiler RTTI.
+ * This does not go into the header. This should only be used in *.cpp files.
+ * Use this with a private getDynamicClassID() in an immediate subclass of UObject.
+ *
+ * @param myClass The name of the class that needs RTTI defined.
+ * @internal
+ */
+#define UOBJECT_DEFINE_NO_RTTI_IMPLEMENTATION(myClass) \
+    UClassID myClass::getDynamicClassID() const { return NULL; }
+
+// /**
+//  * This macro adds ICU RTTI to an ICU concrete class implementation.
+//  * This macro should be invoked in *.cpp files.  The corresponding
+//  * header should declare getDynamicClassID and getStaticClassID.
+//  *
+//  * @param myClass The name of the class that needs RTTI defined.
+//  * @param myParent The name of the myClass's parent.
+//  * @internal
+//  */
+/*#define UOBJECT_DEFINE_RTTI_IMPLEMENTATION(myClass, myParent) \
+    UOBJECT_DEFINE_ABSTRACT_RTTI_IMPLEMENTATION(myClass, myParent) \
+    UClassID myClass::getDynamicClassID() const { \
+        return myClass::getStaticClassID(); \
+    }
+*/
+
+
+U_NAMESPACE_END
+
+#endif