1 /*
2  * Copyright 2012 Google Inc.
3  *
4  * Use of this source code is governed by a BSD-style license that can be
5  * found in the LICENSE file.
6  */
7 
8 #include "include/core/SkRefCnt.h"
9 #include "include/core/SkTypes.h"
10 #include "include/private/SkWeakRefCnt.h"
11 #include "tests/Test.h"
12 
13 #include <thread>
14 
bounce_ref(void * data)15 static void bounce_ref(void* data) {
16     SkRefCnt* ref = static_cast<SkRefCnt*>(data);
17     for (int i = 0; i < 100000; ++i) {
18         ref->ref();
19         ref->unref();
20     }
21 }
22 
test_refCnt(skiatest::Reporter * reporter)23 static void test_refCnt(skiatest::Reporter* reporter) {
24     SkRefCnt* ref = new SkRefCnt();
25 
26     std::thread thing1(bounce_ref, ref);
27     std::thread thing2(bounce_ref, ref);
28 
29     thing1.join();
30     thing2.join();
31 
32     REPORTER_ASSERT(reporter, ref->unique());
33     ref->unref();
34 }
35 
bounce_weak_ref(void * data)36 static void bounce_weak_ref(void* data) {
37     SkWeakRefCnt* ref = static_cast<SkWeakRefCnt*>(data);
38     for (int i = 0; i < 100000; ++i) {
39         if (ref->try_ref()) {
40             ref->unref();
41         }
42     }
43 }
44 
bounce_weak_weak_ref(void * data)45 static void bounce_weak_weak_ref(void* data) {
46     SkWeakRefCnt* ref = static_cast<SkWeakRefCnt*>(data);
47     for (int i = 0; i < 100000; ++i) {
48         ref->weak_ref();
49         ref->weak_unref();
50     }
51 }
52 
test_weakRefCnt(skiatest::Reporter * reporter)53 static void test_weakRefCnt(skiatest::Reporter* reporter) {
54     SkWeakRefCnt* ref = new SkWeakRefCnt();
55 
56     std::thread thing1(bounce_ref, ref);
57     std::thread thing2(bounce_ref, ref);
58     std::thread thing3(bounce_weak_ref, ref);
59     std::thread thing4(bounce_weak_weak_ref, ref);
60 
61     thing1.join();
62     thing2.join();
63     thing3.join();
64     thing4.join();
65 
66     REPORTER_ASSERT(reporter, ref->unique());
67     SkDEBUGCODE(REPORTER_ASSERT(reporter, ref->getWeakCnt() == 1));
68     ref->unref();
69 }
70 
DEF_TEST(RefCnt,reporter)71 DEF_TEST(RefCnt, reporter) {
72     test_refCnt(reporter);
73     test_weakRefCnt(reporter);
74 }
75 
76 ///////////////////////////////////////////////////////////////////////////////////////////////////
77 
78 static int gRefCounter;
79 static int gUnrefCounter;
80 static int gNewCounter;
81 static int gDeleteCounter;
82 
83 #define check(reporter, ref, unref, make, kill)        \
84     REPORTER_ASSERT(reporter, gRefCounter == ref);     \
85     REPORTER_ASSERT(reporter, gUnrefCounter == unref); \
86     REPORTER_ASSERT(reporter, gNewCounter == make);    \
87     REPORTER_ASSERT(reporter, gDeleteCounter == kill)
88 
89 class Effect {
90 public:
Effect()91     Effect() : fRefCnt(1) {
92         gNewCounter += 1;
93     }
~Effect()94     virtual ~Effect() {}
95 
96     int fRefCnt;
97 
ref()98     void ref() {
99         gRefCounter += 1;
100         fRefCnt += 1;
101     }
unref()102     void unref() {
103         gUnrefCounter += 1;
104 
105         SkASSERT(fRefCnt > 0);
106         if (0 == --fRefCnt) {
107             gDeleteCounter += 1;
108             delete this;
109         }
110     }
111 
method() const112     int* method() const { return new int; }
113 };
114 
Create()115 static sk_sp<Effect> Create() {
116     return sk_make_sp<Effect>();
117 }
118 
119 class Paint {
120 public:
121     sk_sp<Effect> fEffect;
122 
get() const123     const sk_sp<Effect>& get() const { return fEffect; }
124 
set(sk_sp<Effect> value)125     void set(sk_sp<Effect> value) {
126         fEffect = std::move(value);
127     }
128 };
129 
130 struct EffectImpl : public Effect {
~EffectImplEffectImpl131     ~EffectImpl() override {}
132 
CreateEffectImpl133     static sk_sp<EffectImpl> Create() {
134         return sk_sp<EffectImpl>(new EffectImpl);
135     }
136     int fValue;
137 };
make_effect()138 static sk_sp<Effect> make_effect() {
139     auto foo = EffectImpl::Create();
140     foo->fValue = 42;
141     return std::move(foo);
142 }
143 
reset_counters()144 static void reset_counters() {
145     gRefCounter = 0;
146     gUnrefCounter = 0;
147     gNewCounter = 0;
148     gDeleteCounter = 0;
149 }
DEF_TEST(sk_sp,reporter)150 DEF_TEST(sk_sp, reporter) {
151     reset_counters();
152 
153     Paint paint;
154     REPORTER_ASSERT(reporter, paint.fEffect.get() == nullptr);
155     REPORTER_ASSERT(reporter, !paint.get());
156     check(reporter, 0, 0, 0, 0);
157 
158     paint.set(Create());
159     check(reporter, 0, 0, 1, 0);
160     REPORTER_ASSERT(reporter, paint.fEffect.get()->fRefCnt == 1);
161 
162     if (paint.get()) {
163         REPORTER_ASSERT(reporter, true);
164     } else {
165         REPORTER_ASSERT(reporter, false);
166     }
167     if (!paint.get()) {
168         REPORTER_ASSERT(reporter, false);
169     } else {
170         REPORTER_ASSERT(reporter, true);
171     }
172 
173     paint.set(nullptr);
174     check(reporter, 0, 1, 1, 1);
175 
176     if (paint.get()) {
177         REPORTER_ASSERT(reporter, false);
178     } else {
179         REPORTER_ASSERT(reporter, true);
180     }
181     if (!paint.get()) {
182         REPORTER_ASSERT(reporter, true);
183     } else {
184         REPORTER_ASSERT(reporter, false);
185     }
186 
187     auto e = Create();
188     REPORTER_ASSERT(reporter, sizeof(e) == sizeof(void*));
189 
190     check(reporter, 0, 1, 2, 1);
191     paint.set(e);
192     check(reporter, 1, 1, 2, 1);
193     REPORTER_ASSERT(reporter, paint.fEffect.get()->fRefCnt == 2);
194 
195     Paint paint2;
196     paint2.set(paint.get());
197     check(reporter, 2, 1, 2, 1);
198     REPORTER_ASSERT(reporter, paint.fEffect.get()->fRefCnt == 3);
199 
200     // Test sk_sp::operator->
201     delete paint.get()->method();
202     check(reporter, 2, 1, 2, 1);
203 
204     // Test sk_sp::operator*
205     delete (*paint.get()).method();
206     check(reporter, 2, 1, 2, 1);
207 
208     paint.set(nullptr);
209     e = nullptr;
210     paint2.set(nullptr);
211     check(reporter, 2, 4, 2, 2);
212 
213     reset_counters();
214     {
215         // Test convertible sk_sp assignment.
216         check(reporter, 0, 0, 0, 0);
217         sk_sp<Effect> foo(nullptr);
218         REPORTER_ASSERT(reporter, !foo);
219         foo = make_effect();
220         REPORTER_ASSERT(reporter, foo);
221         check(reporter, 0, 0, 1, 0);
222     }
223     check(reporter, 0, 1, 1, 1);
224 
225     // Test passing convertible rvalue into funtion.
226     reset_counters();
227     paint.set(EffectImpl::Create());
228     check(reporter, 0, 0, 1, 0);
229     paint.set(nullptr);
230     check(reporter, 0, 1, 1, 1);
231 
232     reset_counters();
233     auto baz = EffectImpl::Create();
234     check(reporter, 0, 0, 1, 0);
235     paint.set(std::move(baz));
236     check(reporter, 0, 0, 1, 0);
237     REPORTER_ASSERT(reporter, !baz);  // NOLINT(bugprone-use-after-move)
238     paint.set(nullptr);
239     check(reporter, 0, 1, 1, 1);
240 
241     reset_counters();
242     {
243         // test comparison operator with convertible type.
244         sk_sp<EffectImpl> bar1 = EffectImpl::Create();
245         sk_sp<Effect> bar2(bar1);  // convertible copy constructor
246         check(reporter, 1, 0, 1, 0);
247         REPORTER_ASSERT(reporter, bar1);
248         REPORTER_ASSERT(reporter, bar2);
249         REPORTER_ASSERT(reporter, bar1 == bar2);
250         REPORTER_ASSERT(reporter, bar2 == bar1);
251         REPORTER_ASSERT(reporter, !(bar1 != bar2));
252         REPORTER_ASSERT(reporter, !(bar2 != bar1));
253         sk_sp<Effect> bar3(nullptr);
254         bar3 = bar1;  // convertible copy assignment
255         check(reporter, 2, 0, 1, 0);
256 
257     }
258     check(reporter, 2, 3, 1, 1);
259 
260     // test passing convertible copy into funtion.
261     reset_counters();
262     baz = EffectImpl::Create();
263     check(reporter, 0, 0, 1, 0);
264     paint.set(baz);
265     check(reporter, 1, 0, 1, 0);
266     baz = nullptr;
267     check(reporter, 1, 1, 1, 0);
268     paint.set(nullptr);
269     check(reporter, 1, 2, 1, 1);
270 
271     {
272         sk_sp<SkRefCnt> empty;
273         sk_sp<SkRefCnt> notEmpty = sk_make_sp<SkRefCnt>();
274         REPORTER_ASSERT(reporter, empty == sk_sp<SkRefCnt>());
275 
276         REPORTER_ASSERT(reporter, notEmpty != empty);
277         REPORTER_ASSERT(reporter, empty != notEmpty);
278 
279         REPORTER_ASSERT(reporter, nullptr == empty);
280         REPORTER_ASSERT(reporter, empty == nullptr);
281         REPORTER_ASSERT(reporter, empty == empty);
282     }
283 
284     {
285         sk_sp<SkRefCnt> a = sk_make_sp<SkRefCnt>();
286         sk_sp<SkRefCnt> b = sk_make_sp<SkRefCnt>();
287         REPORTER_ASSERT(reporter, a != b);
288         REPORTER_ASSERT(reporter, a == a);
289     }
290 
291     // http://wg21.cmeerw.net/lwg/issue998
292     {
293         class foo : public SkRefCnt {
294         public:
295             foo() : bar(this) {}
296             void reset() { bar.reset(); }
297         private:
298             sk_sp<foo> bar;
299         };
300         // The following should properly delete the object and not cause undefined behavior.
301         // This is an ugly example, but the same issue can arise in more subtle ways.
302         (new foo)->reset();
303     }
304 
305     // https://crrev.com/0d4ef2583a6f19c3e61be04d36eb1a60b133832c
306     {
307         struct StructB;
308         struct StructA : public SkRefCnt {
309             sk_sp<StructB> b;
310         };
311 
312         struct StructB : public SkRefCnt {
313             sk_sp<StructA> a;
314             ~StructB() override {} // Some clang versions don't emit this implicitly.
315         };
316 
317         // Create a reference cycle.
318         StructA* a = new StructA;
319         a->b.reset(new StructB);
320         a->b->a.reset(a);
321 
322         // Break the cycle by calling reset(). This will cause |a| (and hence, |a.b|)
323         // to be deleted before the call to reset() returns. This tests that the
324         // implementation of sk_sp::reset() doesn't access |this| after it
325         // deletes the underlying pointer. This behaviour is consistent with the
326         // definition of unique_ptr::reset in C++11.
327         a->b.reset();
328     }
329 }
330 
331 namespace {
332 struct FooAbstract : public SkRefCnt {
333     virtual void f() = 0;
334 };
335 struct FooConcrete : public FooAbstract {
f__anon4490299d0111::FooConcrete336     void f() override {}
337 };
338 }  // namespace
make_foo()339 static sk_sp<FooAbstract> make_foo() {
340     // can not cast FooConcrete to FooAbstract.
341     // can cast FooConcrete* to FooAbstract*.
342     return sk_make_sp<FooConcrete>();
343 }
DEF_TEST(sk_make_sp,r)344 DEF_TEST(sk_make_sp, r) {
345     auto x = make_foo();
346 }
347 
348 // Test that reset() "adopts" ownership from the caller, even if we are given the same ptr twice
349 //
DEF_TEST(sk_sp_reset,r)350 DEF_TEST(sk_sp_reset, r) {
351     SkRefCnt* rc = new SkRefCnt;
352     REPORTER_ASSERT(r, rc->unique());
353 
354     sk_sp<SkRefCnt> sp;
355     sp.reset(rc);
356     // We have transfered our ownership over to sp
357     REPORTER_ASSERT(r, rc->unique());
358 
359     rc->ref();  // now "rc" is also an owner
360     REPORTER_ASSERT(r, !rc->unique());
361 
362     sp.reset(rc);   // this should transfer our ownership over to sp
363     REPORTER_ASSERT(r, rc->unique());
364 }
365 
DEF_TEST(sk_sp_ref,r)366 DEF_TEST(sk_sp_ref, r) {
367     SkRefCnt* rc = new SkRefCnt;
368     REPORTER_ASSERT(r, rc->unique());
369 
370     {
371         sk_sp<SkRefCnt> sp = sk_ref_sp(rc);
372         REPORTER_ASSERT(r, !rc->unique());
373     }
374 
375     REPORTER_ASSERT(r, rc->unique());
376     rc->unref();
377 }
378