The Tor Browser / file revision

 /*

 ******************************************************************************

 *

 *   Copyright (C) 2002-2012, 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"

 /**

  * \file

  * \brief C++ API: Common ICU base class UObject.

  */

 /**

  * @{

  * \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.

  *

  * @stable ICU 4.2

  */

 #ifndef U_NO_THROW

 #define U_NO_THROW throw()

 #endif

 /** @} */

 /*===========================================================================*/

 /* UClassID-based RTTI */

 /*===========================================================================*/

 /**

  * UClassID is used to identify classes without using the compiler's RTTI.

  * This was used before C++ compilers consistently supported RTTI.

  * ICU 4.6 requires compiler RTTI to be turned on.

  *

  * Each class hierarchy which needs

  * to implement polymorphic clone() or operator==() defines two methods,

  * described in detail below.  UClassID values can be compared using

  * operator==(). Nothing else should be done with them.

  *

  * \par

  * In class hierarchies that implement "poor man's RTTI",

  * each concrete subclass implements getDynamicClassID() in the same way:

  *

  * \code

  *      class Derived {

  *      public:

  *          virtual UClassID getDynamicClassID() const

  *            { return Derived::getStaticClassID(); }

  *      }

  * \endcode

  *

  * Each concrete class implements getStaticClassID() as well, which allows

  * clients to test for a specific type.

  *

  * \code

  *      class Derived {

  *      public:

  *          static UClassID U_EXPORT2 getStaticClassID();

  *      private:

  *          static char fgClassID;

  *      }

  *

  *      // In Derived.cpp:

  *      UClassID Derived::getStaticClassID()

  *        { return (UClassID)&Derived::fgClassID; }

  *      char Derived::fgClassID = 0; // Value is irrelevant

  * \endcode

  * @stable ICU 2.0

  */

 typedef void* UClassID;

 U_NAMESPACE_BEGIN

 /**

  * 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, in particular a virtual destructor.

  *

  * 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.

      * The base class implementation returns a dummy value.

      *

      * Use compiler RTTI rather than ICU's "poor man's RTTI".

      * Since ICU 4.6, new ICU C++ class hierarchies do not implement "poor man's RTTI".

      *

      * @stable ICU 2.2

      */

     virtual UClassID getDynamicClassID() const;

 protected:

     // the following functions are protected to prevent instantiation and

     // direct use of UObject itself

     // default constructor

     // inline UObject() {}

     // copy constructor

     // 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 &);

      */

 };

 #ifndef U_HIDE_INTERNAL_API

 /**

  * 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; \

     }

 #endif  /* U_HIDE_INTERNAL_API */

 U_NAMESPACE_END

 #endif