Move ICU headers part 1

public/common/unicode/localpointer.h

-/*
-*******************************************************************************
-*
-*   Copyright (C) 2009-2010, International Business Machines
-*   Corporation and others.  All Rights Reserved.
-*
-*******************************************************************************
-*   file name:  localpointer.h
-*   encoding:   US-ASCII
-*   tab size:   8 (not used)
-*   indentation:4
-*
-*   created on: 2009nov13
-*   created by: Markus W. Scherer
-*/
-
-#ifndef __LOCALPOINTER_H__
-#define __LOCALPOINTER_H__
-
-/**
- * \file 
- * \brief C++ API: "Smart pointers" for use with and in ICU4C C++ code.
- *
- * These classes are inspired by
- * - std::auto_ptr
- * - boost::scoped_ptr & boost::scoped_array
- * - Taligent Safe Pointers (TOnlyPointerTo)
- *
- * but none of those provide for all of the goals for ICU smart pointers:
- * - Smart pointer owns the object and releases it when it goes out of scope.
- * - No transfer of ownership via copy/assignment to reduce misuse. Simpler & more robust.
- * - ICU-compatible: No exceptions.
- * - Need to be able to orphan/release the pointer and its ownership.
- * - Need variants for normal C++ object pointers, C++ arrays, and ICU C service objects.
- *
- * For details see http://site.icu-project.org/design/cpp/scoped_ptr
- */
-
-#include "unicode/utypes.h"
-
-#if U_SHOW_CPLUSPLUS_API
-
-U_NAMESPACE_BEGIN
-
-/**
- * "Smart pointer" base class; do not use directly: use LocalPointer etc.
- *
- * Base class for smart pointer classes that do not throw exceptions.
- *
- * Do not use this base class directly, since it does not delete its pointer.
- * A subclass must implement methods that delete the pointer:
- * Destructor and adoptInstead().
- *
- * There is no operator T *() provided because the programmer must decide
- * whether to use getAlias() (without transfer of ownership) or orpan()
- * (with transfer of ownership and NULLing of the pointer).
- *
- * @see LocalPointer
- * @see LocalArray
- * @see U_DEFINE_LOCAL_OPEN_POINTER
- * @stable ICU 4.4
- */
-template<typename T>
-class LocalPointerBase {
-public:
-    /**
-     * Constructor takes ownership.
-     * @param p simple pointer to an object that is adopted
-     * @stable ICU 4.4
-     */
-    explicit LocalPointerBase(T *p=NULL) : ptr(p) {}
-    /**
-     * Destructor deletes the object it owns.
-     * Subclass must override: Base class does nothing.
-     * @stable ICU 4.4
-     */
-    ~LocalPointerBase() { /* delete ptr; */ }
-    /**
-     * NULL check.
-     * @return TRUE if ==NULL
-     * @stable ICU 4.4
-     */
-    UBool isNull() const { return ptr==NULL; }
-    /**
-     * NULL check.
-     * @return TRUE if !=NULL
-     * @stable ICU 4.4
-     */
-    UBool isValid() const { return ptr!=NULL; }
-    /**
-     * Comparison with a simple pointer, so that existing code
-     * with ==NULL need not be changed.
-     * @param other simple pointer for comparison
-     * @return true if this pointer value equals other
-     * @stable ICU 4.4
-     */
-    bool operator==(const T *other) const { return ptr==other; }
-    /**
-     * Comparison with a simple pointer, so that existing code
-     * with !=NULL need not be changed.
-     * @param other simple pointer for comparison
-     * @return true if this pointer value differs from other
-     * @stable ICU 4.4
-     */
-    bool operator!=(const T *other) const { return ptr!=other; }
-    /**
-     * Access without ownership change.
-     * @return the pointer value
-     * @stable ICU 4.4
-     */
-    T *getAlias() const { return ptr; }
-    /**
-     * Access without ownership change.
-     * @return the pointer value as a reference
-     * @stable ICU 4.4
-     */
-    T &operator*() const { return *ptr; }
-    /**
-     * Access without ownership change.
-     * @return the pointer value
-     * @stable ICU 4.4
-     */
-    T *operator->() const { return ptr; }
-    /**
-     * Gives up ownership; the internal pointer becomes NULL.
-     * @return the pointer value;
-     *         caller becomes responsible for deleting the object
-     * @stable ICU 4.4
-     */
-    T *orphan() {
-        T *p=ptr;
-        ptr=NULL;
-        return p;
-    }
-    /**
-     * Deletes the object it owns,
-     * and adopts (takes ownership of) the one passed in.
-     * Subclass must override: Base class does not delete the object.
-     * @param p simple pointer to an object that is adopted
-     * @stable ICU 4.4
-     */
-    void adoptInstead(T *p) {
-        // delete ptr;
-        ptr=p;
-    }
-protected:
-    T *ptr;
-private:
-    // No comparison operators with other LocalPointerBases.
-    bool operator==(const LocalPointerBase &other);
-    bool operator!=(const LocalPointerBase &other);
-    // No ownership transfer: No copy constructor, no assignment operator.
-    LocalPointerBase(const LocalPointerBase &other);
-    void operator=(const LocalPointerBase &other);
-    // No heap allocation. Use only on the stack.
-    static void * U_EXPORT2 operator new(size_t size);
-    static void * U_EXPORT2 operator new[](size_t size);
-#if U_HAVE_PLACEMENT_NEW
-    static void * U_EXPORT2 operator new(size_t, void *ptr);
-#endif
-};
-
-/**
- * "Smart pointer" class, deletes objects via the standard C++ delete operator.
- * For most methods see the LocalPointerBase base class.
- *
- * Usage example:
- * \code
- * LocalPointer<UnicodeString> s(new UnicodeString((UChar32)0x50005));
- * int32_t length=s->length();  // 2
- * UChar lead=s->charAt(0);  // 0xd900
- * if(some condition) { return; }  // no need to explicitly delete the pointer
- * s.adoptInstead(new UnicodeString((UChar)0xfffc));
- * length=s->length();  // 1
- * // no need to explicitly delete the pointer
- * \endcode
- *
- * @see LocalPointerBase
- * @stable ICU 4.4
- */
-template<typename T>
-class LocalPointer : public LocalPointerBase<T> {
-public:
-    /**
-     * Constructor takes ownership.
-     * @param p simple pointer to an object that is adopted
-     * @stable ICU 4.4
-     */
-    explicit LocalPointer(T *p=NULL) : LocalPointerBase<T>(p) {}
-    /**
-     * Destructor deletes the object it owns.
-     * @stable ICU 4.4
-     */
-    ~LocalPointer() {
-        delete LocalPointerBase<T>::ptr;
-    }
-    /**
-     * Deletes the object it owns,
-     * and adopts (takes ownership of) the one passed in.
-     * @param p simple pointer to an object that is adopted
-     * @stable ICU 4.4
-     */
-    void adoptInstead(T *p) {
-        delete LocalPointerBase<T>::ptr;
-        LocalPointerBase<T>::ptr=p;
-    }
-};
-
-/**
- * "Smart pointer" class, deletes objects via the C++ array delete[] operator.
- * For most methods see the LocalPointerBase base class.
- * Adds operator[] for array item access.
- *
- * Usage example:
- * \code
- * LocalArray<UnicodeString> a(new UnicodeString[2]);
- * a[0].append((UChar)0x61);
- * if(some condition) { return; }  // no need to explicitly delete the array
- * a.adoptInstead(new UnicodeString[4]);
- * a[3].append((UChar)0x62).append((UChar)0x63).reverse();
- * // no need to explicitly delete the array
- * \endcode
- *
- * @see LocalPointerBase
- * @stable ICU 4.4
- */
-template<typename T>
-class LocalArray : public LocalPointerBase<T> {
-public:
-    /**
-     * Constructor takes ownership.
-     * @param p simple pointer to an array of T objects that is adopted
-     * @stable ICU 4.4
-     */
-    explicit LocalArray(T *p=NULL) : LocalPointerBase<T>(p) {}
-    /**
-     * Destructor deletes the array it owns.
-     * @stable ICU 4.4
-     */
-    ~LocalArray() {
-        delete[] LocalPointerBase<T>::ptr;
-    }
-    /**
-     * Deletes the array it owns,
-     * and adopts (takes ownership of) the one passed in.
-     * @param p simple pointer to an array of T objects that is adopted
-     * @stable ICU 4.4
-     */
-    void adoptInstead(T *p) {
-        delete[] LocalPointerBase<T>::ptr;
-        LocalPointerBase<T>::ptr=p;
-    }
-    /**
-     * Array item access (writable).
-     * No index bounds check.
-     * @param i array index
-     * @return reference to the array item
-     * @stable ICU 4.4
-     */
-    T &operator[](ptrdiff_t i) const { return LocalPointerBase<T>::ptr[i]; }
-};
-
-/**
- * \def U_DEFINE_LOCAL_OPEN_POINTER
- * "Smart pointer" definition macro, deletes objects via the closeFunction.
- * Defines a subclass of LocalPointerBase which works just
- * like LocalPointer<Type> except that this subclass will use the closeFunction
- * rather than the C++ delete operator.
- *
- * Requirement: The closeFunction must tolerate a NULL pointer.
- * (We could add a NULL check here but it is normally redundant.)
- *
- * Usage example:
- * \code
- * LocalUCaseMapPointer csm(ucasemap_open(localeID, options, &errorCode));
- * utf8OutLength=ucasemap_utf8ToLower(csm.getAlias(),
- *     utf8Out, (int32_t)sizeof(utf8Out),
- *     utf8In, utf8InLength, &errorCode);
- * if(U_FAILURE(errorCode)) { return; }  // no need to explicitly delete the UCaseMap
- * \endcode
- *
- * @see LocalPointerBase
- * @see LocalPointer
- * @stable ICU 4.4
- */
-#define U_DEFINE_LOCAL_OPEN_POINTER(LocalPointerClassName, Type, closeFunction) \
-    class LocalPointerClassName : public LocalPointerBase<Type> { \
-    public: \
-        explicit LocalPointerClassName(Type *p=NULL) : LocalPointerBase<Type>(p) {} \
-        ~LocalPointerClassName() { closeFunction(ptr); } \
-        void adoptInstead(Type *p) { \
-            closeFunction(ptr); \
-            ptr=p; \
-        } \
-    }
-
-U_NAMESPACE_END
-
-#endif  /* U_SHOW_CPLUSPLUS_API */
-#endif  /* __LOCALPOINTER_H__ */