00001
00002
00003
00004
00005
00006
00007
00008
00009
00010
00011
00012
00013
00014
00015
00016
00017
00018
00019
00020
00021
00022
00023
00024
00025
00026
00027
00028
00029
00030
00031
00032
00033
00034
00035
00036
00037
00038
00039
00040
00041 #ifndef yasper_ptr_h
00042 #define yasper_ptr_h
00043
00044 namespace yasper
00045 {
00046
00047 #include <exception>
00048 #include <string>
00049
00050 struct NullPointerException : public std::exception
00051 {
00052 NullPointerException() throw() {}
00053
00054 ~NullPointerException() throw() {}
00055
00056 const char* what() const throw()
00057 {
00058 return "[Yasper Exception] Attempted to dereference null pointer";
00059 }
00060 };
00061
00062 template <typename X>
00063 class ptr
00064 {
00065
00066 public:
00067 typedef X element_type;
00068
00069
00070
00071
00072
00073 template <class Y> friend class ptr;
00074
00075
00076
00077
00078 ptr() : rawPtr(0), counter(0)
00079 {
00080 }
00081
00082
00083
00084
00085 ptr(X* raw) : rawPtr(0), counter(0)
00086 {
00087 if (raw)
00088 {
00089 rawPtr = raw;
00090 counter = new Counter;
00091 }
00092 }
00093
00094 template <typename Y>
00095 ptr(Y* raw) : rawPtr(0), counter(0)
00096 {
00097 if (raw)
00098 {
00099 rawPtr = static_cast<X*>( raw );
00100 counter = new Counter;
00101 }
00102 }
00103
00104
00105
00106
00107 ptr(const ptr< X >& otherPtr)
00108 {
00109 acquire( otherPtr.counter );
00110 rawPtr = otherPtr.rawPtr;
00111 }
00112
00113 template <typename Y>
00114 ptr(const ptr< Y >& otherPtr) : rawPtr(0), counter(0)
00115 {
00116 acquire( (Counter*) (otherPtr.counter) );
00117 rawPtr = static_cast<X*>( otherPtr.GetRawPointer());
00118 }
00119
00120
00121
00122
00123
00124 ~ptr()
00125 {
00126 release();
00127 }
00128
00129
00130
00131
00132
00133 ptr& operator=(const ptr< X >& otherPtr)
00134 {
00135 if (this != &otherPtr)
00136 {
00137 release();
00138 acquire(otherPtr.counter);
00139 rawPtr = otherPtr.rawPtr;
00140 }
00141 return *this;
00142 }
00143
00144 template <typename Y>
00145 ptr& operator=(const ptr< Y >& otherPtr)
00146 {
00147 if ( this != (ptr< X >*) &otherPtr )
00148 {
00149 release();
00150 acquire( (Counter*)(otherPtr.counter) );
00151 rawPtr = static_cast<X*> (otherPtr.GetRawPointer());
00152 }
00153 return *this;
00154 }
00155
00156
00157
00158
00159
00160
00161
00162
00163 ptr& operator=(X* raw)
00164 {
00165 if (raw)
00166 {
00167 release();
00168 counter = new Counter;
00169 rawPtr = raw;
00170 }
00171 return *this;
00172 }
00173
00174 template <typename Y>
00175 ptr& operator=(Y* raw)
00176 {
00177 if (raw)
00178 {
00179 release();
00180 counter = new Counter;
00181 rawPtr = static_cast<X*>(raw);
00182 }
00183 return *this;
00184 }
00185
00186
00187
00188
00189
00190
00191
00192
00193 ptr& operator=(long num)
00194 {
00195 if (num == 0)
00196 {
00197 release();
00198 }
00199
00200 else
00201 {
00202 release();
00203 counter = new Counter;
00204 rawPtr = reinterpret_cast<X*>(num);
00205 }
00206
00207 return *this;
00208 }
00209
00210
00211
00212
00213 X* operator->() const
00214 {
00215 return GetRawPointer();
00216 }
00217
00218
00219
00220
00221
00222 X& operator* () const
00223 {
00224 return *GetRawPointer();
00225 }
00226
00227
00228
00229
00230
00231 operator bool() const
00232 {
00233 return IsValid();
00234 }
00235
00236 template <typename Y>
00237 operator Y*() const
00238 {
00239 return static_cast<Y*>(rawPtr);
00240 }
00241
00242 template <typename Y>
00243 operator const Y*() const
00244 {
00245 return static_cast<const Y*>(rawPtr);
00246 }
00247
00248
00249
00250
00251
00252
00253 X* GetRawPointer() const
00254 {
00255 if (rawPtr == 0) throw new NullPointerException;
00256 return rawPtr;
00257 }
00258
00259
00260
00261
00262
00263 bool IsUnique() const
00264 {
00265 if (counter && counter->count == 1) return true;
00266 else return false;
00267 }
00268
00269 bool IsValid() const
00270 {
00271 if (counter && rawPtr) return true;
00272 else return false;
00273 }
00274
00275 unsigned GetCount() const
00276 {
00277 if (counter) return counter->count;
00278 else return 0;
00279 }
00280
00281 private:
00282 X* rawPtr;
00283
00284 struct Counter
00285 {
00286 Counter(unsigned c = 1) : count(c) {}
00287 unsigned count;
00288 };
00289
00290 Counter* counter;
00291
00292
00293 void acquire(Counter* c)
00294 {
00295 counter = c;
00296 if (c)
00297 {
00298 (c->count)++;
00299 }
00300 }
00301
00302
00303 void release()
00304 {
00305 if (counter)
00306 {
00307 (counter->count)--;
00308
00309 if (counter->count == 0)
00310 {
00311 delete rawPtr;
00312 delete counter;
00313 }
00314 }
00315 counter = 0;
00316 rawPtr = 0;
00317
00318 }
00319 };
00320
00321
00322 template <typename X, typename Y>
00323 bool operator==(const ptr< X >& lptr, const ptr< Y >& rptr)
00324 {
00325 return lptr.GetRawPointer() == rptr.GetRawPointer();
00326 }
00327
00328 template <typename X, typename Y>
00329 bool operator==(const ptr< X >& lptr, Y* raw)
00330 {
00331 return lptr.GetRawPointer() == raw ;
00332 }
00333
00334 template <typename X>
00335 bool operator==(const ptr< X >& lptr, long num)
00336 {
00337 if (num == 0 && !lptr.IsValid())
00338 {
00339 return true;
00340 }
00341
00342 else
00343 {
00344 return lptr == reinterpret_cast<X*>(num);
00345 }
00346
00347 }
00348
00349 template <typename X, typename Y>
00350 bool operator!=(const ptr< X >& lptr, const ptr< Y >& rptr)
00351 {
00352 return ( !operator==(lptr, rptr) );
00353 }
00354
00355 template <typename X, typename Y>
00356 bool operator!=(const ptr< X >& lptr, Y* raw)
00357 {
00358 return ( !operator==(lptr, raw) );
00359 }
00360
00361 template <typename X>
00362 bool operator!=(const ptr< X >& lptr, long num)
00363 {
00364 return (!operator==(lptr, num) );
00365 }
00366
00367 template <typename X, typename Y>
00368 bool operator&&(const ptr< X >& lptr, const ptr< Y >& rptr)
00369 {
00370 return lptr.IsValid() && rptr.IsValid();
00371 }
00372
00373 template <typename X>
00374 bool operator&&(const ptr< X >& lptr, bool rval)
00375 {
00376 return lptr.IsValid() && rval;
00377 }
00378
00379 template <typename X>
00380 bool operator&&(bool lval, const ptr< X >& rptr)
00381 {
00382 return lval && rptr.IsValid();
00383 }
00384
00385 template <typename X, typename Y>
00386 bool operator||(const ptr< X >& lptr, const ptr< Y >& rptr)
00387 {
00388 return lptr.IsValid() || rptr.IsValid();
00389 }
00390
00391 template <typename X>
00392 bool operator||(const ptr< X >& lptr, bool rval)
00393 {
00394 return lptr.IsValid() || rval;
00395 }
00396
00397 template <typename X>
00398 bool operator||(bool lval, const ptr< X >& rptr)
00399 {
00400 return lval || rptr.IsValid();
00401 }
00402
00403 template <typename X>
00404 bool operator!(const ptr< X >& p)
00405 {
00406 return (!p.IsValid());
00407 }
00408
00409
00410
00411 template <typename X, typename Y>
00412 bool operator< (const ptr< X >& lptr, const ptr < Y >& rptr)
00413 {
00414 return lptr.GetRawPointer() < rptr.GetRawPointer();
00415 }
00416
00417 template <typename X, typename Y>
00418 bool operator< (const ptr< X >& lptr, Y* raw)
00419 {
00420 return lptr.GetRawPointer() < raw;
00421 }
00422
00423 template <typename X, typename Y>
00424 bool operator< (X* raw, const ptr< Y >& rptr)
00425 {
00426 return raw < rptr.GetRawPointer();
00427 }
00428
00429 }
00430 #endif
00431