media/omx-plugin/include/gb/utils/RefBase.h@b8a032363ba2
media/omx-plugin/include/gb/utils/RefBase.h
Thu, 22 Jan 2015 13:21:57 +0100
- author
- Michael Schloh von Bennewitz <michael@schloh.com>
- date
- Thu, 22 Jan 2015 13:21:57 +0100
- branch
- TOR_BUG_9701
- changeset 15
- b8a032363ba2
- permissions
- -rw-r--r--
Incorporate requested changes from Mozilla in review:
https://bugzilla.mozilla.org/show_bug.cgi?id=1123480#c6
1 /*
2 * Copyright (C) 2005 The Android Open Source Project
3 *
4 * Licensed under the Apache License, Version 2.0 (the "License");
5 * you may not use this file except in compliance with the License.
6 * You may obtain a copy of the License at
7 *
8 * http://www.apache.org/licenses/LICENSE-2.0
9 *
10 * Unless required by applicable law or agreed to in writing, software
11 * distributed under the License is distributed on an "AS IS" BASIS,
12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 * See the License for the specific language governing permissions and
14 * limitations under the License.
15 */
17 #ifndef ANDROID_REF_BASE_H
18 #define ANDROID_REF_BASE_H
20 #include <cutils/atomic.h>
21 #include <utils/TextOutput.h>
23 #include <stdint.h>
24 #include <sys/types.h>
25 #include <stdlib.h>
27 // ---------------------------------------------------------------------------
28 namespace android {
30 template<typename T> class wp;
32 // ---------------------------------------------------------------------------
34 #define COMPARE_WEAK(_op_) \
35 inline bool operator _op_ (const sp<T>& o) const { \
36 return m_ptr _op_ o.m_ptr; \
37 } \
38 inline bool operator _op_ (const T* o) const { \
39 return m_ptr _op_ o; \
40 } \
41 template<typename U> \
42 inline bool operator _op_ (const sp<U>& o) const { \
43 return m_ptr _op_ o.m_ptr; \
44 } \
45 template<typename U> \
46 inline bool operator _op_ (const U* o) const { \
47 return m_ptr _op_ o; \
48 }
50 #define COMPARE(_op_) \
51 COMPARE_WEAK(_op_) \
52 inline bool operator _op_ (const wp<T>& o) const { \
53 return m_ptr _op_ o.m_ptr; \
54 } \
55 template<typename U> \
56 inline bool operator _op_ (const wp<U>& o) const { \
57 return m_ptr _op_ o.m_ptr; \
58 }
60 // ---------------------------------------------------------------------------
62 class RefBase
63 {
64 public:
65 void incStrong(const void* id) const;
66 void decStrong(const void* id) const;
68 void forceIncStrong(const void* id) const;
70 //! DEBUGGING ONLY: Get current strong ref count.
71 int32_t getStrongCount() const;
73 class weakref_type
74 {
75 public:
76 RefBase* refBase() const;
78 void incWeak(const void* id);
79 void decWeak(const void* id);
81 bool attemptIncStrong(const void* id);
83 //! This is only safe if you have set OBJECT_LIFETIME_FOREVER.
84 bool attemptIncWeak(const void* id);
86 //! DEBUGGING ONLY: Get current weak ref count.
87 int32_t getWeakCount() const;
89 //! DEBUGGING ONLY: Print references held on object.
90 void printRefs() const;
92 //! DEBUGGING ONLY: Enable tracking for this object.
93 // enable -- enable/disable tracking
94 // retain -- when tracking is enable, if true, then we save a stack trace
95 // for each reference and dereference; when retain == false, we
96 // match up references and dereferences and keep only the
97 // outstanding ones.
99 void trackMe(bool enable, bool retain);
100 };
102 weakref_type* createWeak(const void* id) const;
104 weakref_type* getWeakRefs() const;
106 //! DEBUGGING ONLY: Print references held on object.
107 inline void printRefs() const { getWeakRefs()->printRefs(); }
109 //! DEBUGGING ONLY: Enable tracking of object.
110 inline void trackMe(bool enable, bool retain)
111 {
112 getWeakRefs()->trackMe(enable, retain);
113 }
115 // used to override the RefBase destruction.
116 class Destroyer {
117 friend class RefBase;
118 public:
119 virtual ~Destroyer();
120 private:
121 virtual void destroy(RefBase const* base) = 0;
122 };
124 // Make sure to never acquire a strong reference from this function. The
125 // same restrictions than for destructors apply.
126 void setDestroyer(Destroyer* destroyer);
128 protected:
129 RefBase();
130 virtual ~RefBase();
132 //! Flags for extendObjectLifetime()
133 enum {
134 OBJECT_LIFETIME_WEAK = 0x0001,
135 OBJECT_LIFETIME_FOREVER = 0x0003
136 };
138 void extendObjectLifetime(int32_t mode);
140 //! Flags for onIncStrongAttempted()
141 enum {
142 FIRST_INC_STRONG = 0x0001
143 };
145 virtual void onFirstRef();
146 virtual void onLastStrongRef(const void* id);
147 virtual bool onIncStrongAttempted(uint32_t flags, const void* id);
148 virtual void onLastWeakRef(const void* id);
150 private:
151 friend class weakref_type;
152 class weakref_impl;
154 RefBase(const RefBase& o);
155 RefBase& operator=(const RefBase& o);
157 weakref_impl* const mRefs;
158 };
160 // ---------------------------------------------------------------------------
162 template <class T>
163 class LightRefBase
164 {
165 public:
166 inline LightRefBase() : mCount(0) { }
167 inline void incStrong(const void* id) const {
168 android_atomic_inc(&mCount);
169 }
170 inline void decStrong(const void* id) const {
171 if (android_atomic_dec(&mCount) == 1) {
172 delete static_cast<const T*>(this);
173 }
174 }
175 //! DEBUGGING ONLY: Get current strong ref count.
176 inline int32_t getStrongCount() const {
177 return mCount;
178 }
180 protected:
181 inline ~LightRefBase() { }
183 private:
184 mutable volatile int32_t mCount;
185 };
187 // ---------------------------------------------------------------------------
189 template <typename T>
190 class sp
191 {
192 public:
193 typedef typename RefBase::weakref_type weakref_type;
195 inline sp() : m_ptr(0) { }
197 sp(T* other);
198 sp(const sp<T>& other);
199 template<typename U> sp(U* other);
200 template<typename U> sp(const sp<U>& other);
202 ~sp();
204 // Assignment
206 sp& operator = (T* other);
207 sp& operator = (const sp<T>& other);
209 template<typename U> sp& operator = (const sp<U>& other);
210 template<typename U> sp& operator = (U* other);
212 //! Special optimization for use by ProcessState (and nobody else).
213 void force_set(T* other);
215 // Reset
217 void clear();
219 // Accessors
221 inline T& operator* () const { return *m_ptr; }
222 inline T* operator-> () const { return m_ptr; }
223 inline T* get() const { return m_ptr; }
225 // Operators
227 COMPARE(==)
228 COMPARE(!=)
229 COMPARE(>)
230 COMPARE(<)
231 COMPARE(<=)
232 COMPARE(>=)
234 private:
235 template<typename Y> friend class sp;
236 template<typename Y> friend class wp;
238 // Optimization for wp::promote().
239 sp(T* p, weakref_type* refs);
241 T* m_ptr;
242 };
244 template <typename T>
245 TextOutput& operator<<(TextOutput& to, const sp<T>& val);
247 // ---------------------------------------------------------------------------
249 template <typename T>
250 class wp
251 {
252 public:
253 typedef typename RefBase::weakref_type weakref_type;
255 inline wp() : m_ptr(0) { }
257 wp(T* other);
258 wp(const wp<T>& other);
259 wp(const sp<T>& other);
260 template<typename U> wp(U* other);
261 template<typename U> wp(const sp<U>& other);
262 template<typename U> wp(const wp<U>& other);
264 ~wp();
266 // Assignment
268 wp& operator = (T* other);
269 wp& operator = (const wp<T>& other);
270 wp& operator = (const sp<T>& other);
272 template<typename U> wp& operator = (U* other);
273 template<typename U> wp& operator = (const wp<U>& other);
274 template<typename U> wp& operator = (const sp<U>& other);
276 void set_object_and_refs(T* other, weakref_type* refs);
278 // promotion to sp
280 sp<T> promote() const;
282 // Reset
284 void clear();
286 // Accessors
288 inline weakref_type* get_refs() const { return m_refs; }
290 inline T* unsafe_get() const { return m_ptr; }
292 // Operators
294 COMPARE_WEAK(==)
295 COMPARE_WEAK(!=)
296 COMPARE_WEAK(>)
297 COMPARE_WEAK(<)
298 COMPARE_WEAK(<=)
299 COMPARE_WEAK(>=)
301 inline bool operator == (const wp<T>& o) const {
302 return (m_ptr == o.m_ptr) && (m_refs == o.m_refs);
303 }
304 template<typename U>
305 inline bool operator == (const wp<U>& o) const {
306 return m_ptr == o.m_ptr;
307 }
309 inline bool operator > (const wp<T>& o) const {
310 return (m_ptr == o.m_ptr) ? (m_refs > o.m_refs) : (m_ptr > o.m_ptr);
311 }
312 template<typename U>
313 inline bool operator > (const wp<U>& o) const {
314 return (m_ptr == o.m_ptr) ? (m_refs > o.m_refs) : (m_ptr > o.m_ptr);
315 }
317 inline bool operator < (const wp<T>& o) const {
318 return (m_ptr == o.m_ptr) ? (m_refs < o.m_refs) : (m_ptr < o.m_ptr);
319 }
320 template<typename U>
321 inline bool operator < (const wp<U>& o) const {
322 return (m_ptr == o.m_ptr) ? (m_refs < o.m_refs) : (m_ptr < o.m_ptr);
323 }
324 inline bool operator != (const wp<T>& o) const { return m_refs != o.m_refs; }
325 template<typename U> inline bool operator != (const wp<U>& o) const { return !operator == (o); }
326 inline bool operator <= (const wp<T>& o) const { return !operator > (o); }
327 template<typename U> inline bool operator <= (const wp<U>& o) const { return !operator > (o); }
328 inline bool operator >= (const wp<T>& o) const { return !operator < (o); }
329 template<typename U> inline bool operator >= (const wp<U>& o) const { return !operator < (o); }
331 private:
332 template<typename Y> friend class sp;
333 template<typename Y> friend class wp;
335 T* m_ptr;
336 weakref_type* m_refs;
337 };
339 template <typename T>
340 TextOutput& operator<<(TextOutput& to, const wp<T>& val);
342 #undef COMPARE
343 #undef COMPARE_WEAK
345 // ---------------------------------------------------------------------------
346 // No user serviceable parts below here.
348 template<typename T>
349 sp<T>::sp(T* other)
350 : m_ptr(other)
351 {
352 if (other) other->incStrong(this);
353 }
355 template<typename T>
356 sp<T>::sp(const sp<T>& other)
357 : m_ptr(other.m_ptr)
358 {
359 if (m_ptr) m_ptr->incStrong(this);
360 }
362 template<typename T> template<typename U>
363 sp<T>::sp(U* other) : m_ptr(other)
364 {
365 if (other) other->incStrong(this);
366 }
368 template<typename T> template<typename U>
369 sp<T>::sp(const sp<U>& other)
370 : m_ptr(other.m_ptr)
371 {
372 if (m_ptr) m_ptr->incStrong(this);
373 }
375 template<typename T>
376 sp<T>::~sp()
377 {
378 if (m_ptr) m_ptr->decStrong(this);
379 }
381 template<typename T>
382 sp<T>& sp<T>::operator = (const sp<T>& other) {
383 T* otherPtr(other.m_ptr);
384 if (otherPtr) otherPtr->incStrong(this);
385 if (m_ptr) m_ptr->decStrong(this);
386 m_ptr = otherPtr;
387 return *this;
388 }
390 template<typename T>
391 sp<T>& sp<T>::operator = (T* other)
392 {
393 if (other) other->incStrong(this);
394 if (m_ptr) m_ptr->decStrong(this);
395 m_ptr = other;
396 return *this;
397 }
399 template<typename T> template<typename U>
400 sp<T>& sp<T>::operator = (const sp<U>& other)
401 {
402 U* otherPtr(other.m_ptr);
403 if (otherPtr) otherPtr->incStrong(this);
404 if (m_ptr) m_ptr->decStrong(this);
405 m_ptr = otherPtr;
406 return *this;
407 }
409 template<typename T> template<typename U>
410 sp<T>& sp<T>::operator = (U* other)
411 {
412 if (other) other->incStrong(this);
413 if (m_ptr) m_ptr->decStrong(this);
414 m_ptr = other;
415 return *this;
416 }
418 template<typename T>
419 void sp<T>::force_set(T* other)
420 {
421 other->forceIncStrong(this);
422 m_ptr = other;
423 }
425 template<typename T>
426 void sp<T>::clear()
427 {
428 if (m_ptr) {
429 m_ptr->decStrong(this);
430 m_ptr = 0;
431 }
432 }
434 template<typename T>
435 sp<T>::sp(T* p, weakref_type* refs)
436 : m_ptr((p && refs->attemptIncStrong(this)) ? p : 0)
437 {
438 }
440 template <typename T>
441 inline TextOutput& operator<<(TextOutput& to, const sp<T>& val)
442 {
443 to << "sp<>(" << val.get() << ")";
444 return to;
445 }
447 // ---------------------------------------------------------------------------
449 template<typename T>
450 wp<T>::wp(T* other)
451 : m_ptr(other)
452 {
453 if (other) m_refs = other->createWeak(this);
454 }
456 template<typename T>
457 wp<T>::wp(const wp<T>& other)
458 : m_ptr(other.m_ptr), m_refs(other.m_refs)
459 {
460 if (m_ptr) m_refs->incWeak(this);
461 }
463 template<typename T>
464 wp<T>::wp(const sp<T>& other)
465 : m_ptr(other.m_ptr)
466 {
467 if (m_ptr) {
468 m_refs = m_ptr->createWeak(this);
469 }
470 }
472 template<typename T> template<typename U>
473 wp<T>::wp(U* other)
474 : m_ptr(other)
475 {
476 if (other) m_refs = other->createWeak(this);
477 }
479 template<typename T> template<typename U>
480 wp<T>::wp(const wp<U>& other)
481 : m_ptr(other.m_ptr)
482 {
483 if (m_ptr) {
484 m_refs = other.m_refs;
485 m_refs->incWeak(this);
486 }
487 }
489 template<typename T> template<typename U>
490 wp<T>::wp(const sp<U>& other)
491 : m_ptr(other.m_ptr)
492 {
493 if (m_ptr) {
494 m_refs = m_ptr->createWeak(this);
495 }
496 }
498 template<typename T>
499 wp<T>::~wp()
500 {
501 if (m_ptr) m_refs->decWeak(this);
502 }
504 template<typename T>
505 wp<T>& wp<T>::operator = (T* other)
506 {
507 weakref_type* newRefs =
508 other ? other->createWeak(this) : 0;
509 if (m_ptr) m_refs->decWeak(this);
510 m_ptr = other;
511 m_refs = newRefs;
512 return *this;
513 }
515 template<typename T>
516 wp<T>& wp<T>::operator = (const wp<T>& other)
517 {
518 weakref_type* otherRefs(other.m_refs);
519 T* otherPtr(other.m_ptr);
520 if (otherPtr) otherRefs->incWeak(this);
521 if (m_ptr) m_refs->decWeak(this);
522 m_ptr = otherPtr;
523 m_refs = otherRefs;
524 return *this;
525 }
527 template<typename T>
528 wp<T>& wp<T>::operator = (const sp<T>& other)
529 {
530 weakref_type* newRefs =
531 other != NULL ? other->createWeak(this) : 0;
532 T* otherPtr(other.m_ptr);
533 if (m_ptr) m_refs->decWeak(this);
534 m_ptr = otherPtr;
535 m_refs = newRefs;
536 return *this;
537 }
539 template<typename T> template<typename U>
540 wp<T>& wp<T>::operator = (U* other)
541 {
542 weakref_type* newRefs =
543 other ? other->createWeak(this) : 0;
544 if (m_ptr) m_refs->decWeak(this);
545 m_ptr = other;
546 m_refs = newRefs;
547 return *this;
548 }
550 template<typename T> template<typename U>
551 wp<T>& wp<T>::operator = (const wp<U>& other)
552 {
553 weakref_type* otherRefs(other.m_refs);
554 U* otherPtr(other.m_ptr);
555 if (otherPtr) otherRefs->incWeak(this);
556 if (m_ptr) m_refs->decWeak(this);
557 m_ptr = otherPtr;
558 m_refs = otherRefs;
559 return *this;
560 }
562 template<typename T> template<typename U>
563 wp<T>& wp<T>::operator = (const sp<U>& other)
564 {
565 weakref_type* newRefs =
566 other != NULL ? other->createWeak(this) : 0;
567 U* otherPtr(other.m_ptr);
568 if (m_ptr) m_refs->decWeak(this);
569 m_ptr = otherPtr;
570 m_refs = newRefs;
571 return *this;
572 }
574 template<typename T>
575 void wp<T>::set_object_and_refs(T* other, weakref_type* refs)
576 {
577 if (other) refs->incWeak(this);
578 if (m_ptr) m_refs->decWeak(this);
579 m_ptr = other;
580 m_refs = refs;
581 }
583 template<typename T>
584 sp<T> wp<T>::promote() const
585 {
586 return sp<T>(m_ptr, m_refs);
587 }
589 template<typename T>
590 void wp<T>::clear()
591 {
592 if (m_ptr) {
593 m_refs->decWeak(this);
594 m_ptr = 0;
595 }
596 }
598 template <typename T>
599 inline TextOutput& operator<<(TextOutput& to, const wp<T>& val)
600 {
601 to << "wp<>(" << val.unsafe_get() << ")";
602 return to;
603 }
605 }; // namespace android
607 // ---------------------------------------------------------------------------
609 #endif // ANDROID_REF_BASE_H
