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1 // Copyright 2014 The Chromium Authors. All rights reserved.
2 // Use of this source code is governed by a BSD-style license that can be
3 // found in the LICENSE file.
4 
5 // This file tests the C++ Mojo system core wrappers.
6 // TODO(vtl): Maybe rename "CoreCppTest" -> "CoreTest" if/when this gets
7 // compiled into a different binary from the C API tests.
8 
9 #include "mojo/public/cpp/system/core.h"
10 
11 #include <stddef.h>
12 #include <stdint.h>
13 #include <map>
14 #include <utility>
15 
16 #include "testing/gtest/include/gtest/gtest.h"
17 
18 namespace mojo {
19 namespace {
20 
21 const MojoHandleSignals kSignalReadableWritable =
22     MOJO_HANDLE_SIGNAL_READABLE | MOJO_HANDLE_SIGNAL_WRITABLE;
23 
24 const MojoHandleSignals kSignalAll = MOJO_HANDLE_SIGNAL_READABLE |
25                                      MOJO_HANDLE_SIGNAL_WRITABLE |
26                                      MOJO_HANDLE_SIGNAL_PEER_CLOSED;
27 
TEST(CoreCppTest,GetTimeTicksNow)28 TEST(CoreCppTest, GetTimeTicksNow) {
29   const MojoTimeTicks start = GetTimeTicksNow();
30   EXPECT_NE(static_cast<MojoTimeTicks>(0), start)
31       << "GetTimeTicksNow should return nonzero value";
32 }
33 
TEST(CoreCppTest,Basic)34 TEST(CoreCppTest, Basic) {
35   // Basic |Handle| implementation:
36   {
37     EXPECT_EQ(MOJO_HANDLE_INVALID, kInvalidHandleValue);
38 
39     Handle h0;
40     EXPECT_EQ(kInvalidHandleValue, h0.value());
41     EXPECT_EQ(kInvalidHandleValue, *h0.mutable_value());
42     EXPECT_FALSE(h0.is_valid());
43 
44     Handle h1(static_cast<MojoHandle>(123));
45     EXPECT_EQ(static_cast<MojoHandle>(123), h1.value());
46     EXPECT_EQ(static_cast<MojoHandle>(123), *h1.mutable_value());
47     EXPECT_TRUE(h1.is_valid());
48     *h1.mutable_value() = static_cast<MojoHandle>(456);
49     EXPECT_EQ(static_cast<MojoHandle>(456), h1.value());
50     EXPECT_TRUE(h1.is_valid());
51 
52     h1.swap(h0);
53     EXPECT_EQ(static_cast<MojoHandle>(456), h0.value());
54     EXPECT_TRUE(h0.is_valid());
55     EXPECT_FALSE(h1.is_valid());
56 
57     h1.set_value(static_cast<MojoHandle>(789));
58     h0.swap(h1);
59     EXPECT_EQ(static_cast<MojoHandle>(789), h0.value());
60     EXPECT_TRUE(h0.is_valid());
61     EXPECT_EQ(static_cast<MojoHandle>(456), h1.value());
62     EXPECT_TRUE(h1.is_valid());
63 
64     // Make sure copy constructor works.
65     Handle h2(h0);
66     EXPECT_EQ(static_cast<MojoHandle>(789), h2.value());
67     // And assignment.
68     h2 = h1;
69     EXPECT_EQ(static_cast<MojoHandle>(456), h2.value());
70 
71     // Make sure that we can put |Handle|s into |std::map|s.
72     h0 = Handle(static_cast<MojoHandle>(987));
73     h1 = Handle(static_cast<MojoHandle>(654));
74     h2 = Handle(static_cast<MojoHandle>(321));
75     Handle h3;
76     std::map<Handle, int> handle_to_int;
77     handle_to_int[h0] = 0;
78     handle_to_int[h1] = 1;
79     handle_to_int[h2] = 2;
80     handle_to_int[h3] = 3;
81 
82     EXPECT_EQ(4u, handle_to_int.size());
83     EXPECT_FALSE(handle_to_int.find(h0) == handle_to_int.end());
84     EXPECT_EQ(0, handle_to_int[h0]);
85     EXPECT_FALSE(handle_to_int.find(h1) == handle_to_int.end());
86     EXPECT_EQ(1, handle_to_int[h1]);
87     EXPECT_FALSE(handle_to_int.find(h2) == handle_to_int.end());
88     EXPECT_EQ(2, handle_to_int[h2]);
89     EXPECT_FALSE(handle_to_int.find(h3) == handle_to_int.end());
90     EXPECT_EQ(3, handle_to_int[h3]);
91     EXPECT_TRUE(handle_to_int.find(Handle(static_cast<MojoHandle>(13579))) ==
92                 handle_to_int.end());
93 
94     // TODO(vtl): With C++11, support |std::unordered_map|s, etc. (Or figure out
95     // how to support the variations of |hash_map|.)
96   }
97 
98   // |Handle|/|ScopedHandle| functions:
99   {
100     ScopedHandle h;
101 
102     EXPECT_EQ(kInvalidHandleValue, h.get().value());
103 
104     // This should be a no-op.
105     Close(std::move(h));
106 
107     // It should still be invalid.
108     EXPECT_EQ(kInvalidHandleValue, h.get().value());
109 
110     EXPECT_EQ(MOJO_RESULT_INVALID_ARGUMENT,
111               Wait(h.get(), ~MOJO_HANDLE_SIGNAL_NONE, 1000000, nullptr));
112 
113     std::vector<Handle> wh;
114     wh.push_back(h.get());
115     std::vector<MojoHandleSignals> sigs;
116     sigs.push_back(~MOJO_HANDLE_SIGNAL_NONE);
117     WaitManyResult wait_many_result =
118         WaitMany(wh, sigs, MOJO_DEADLINE_INDEFINITE, nullptr);
119     EXPECT_EQ(MOJO_RESULT_INVALID_ARGUMENT, wait_many_result.result);
120     EXPECT_TRUE(wait_many_result.IsIndexValid());
121     EXPECT_FALSE(wait_many_result.AreSignalsStatesValid());
122 
123     // Make sure that our specialized template correctly handles |NULL| as well
124     // as |nullptr|.
125     wait_many_result = WaitMany(wh, sigs, MOJO_DEADLINE_INDEFINITE, NULL);
126     EXPECT_EQ(MOJO_RESULT_INVALID_ARGUMENT, wait_many_result.result);
127     EXPECT_EQ(0u, wait_many_result.index);
128     EXPECT_TRUE(wait_many_result.IsIndexValid());
129     EXPECT_FALSE(wait_many_result.AreSignalsStatesValid());
130   }
131 
132   // |MakeScopedHandle| (just compilation tests):
133   {
134     EXPECT_FALSE(MakeScopedHandle(Handle()).is_valid());
135     EXPECT_FALSE(MakeScopedHandle(MessagePipeHandle()).is_valid());
136     EXPECT_FALSE(MakeScopedHandle(DataPipeProducerHandle()).is_valid());
137     EXPECT_FALSE(MakeScopedHandle(DataPipeConsumerHandle()).is_valid());
138     EXPECT_FALSE(MakeScopedHandle(SharedBufferHandle()).is_valid());
139   }
140 
141   // |MessagePipeHandle|/|ScopedMessagePipeHandle| functions:
142   {
143     MessagePipeHandle h_invalid;
144     EXPECT_FALSE(h_invalid.is_valid());
145     EXPECT_EQ(
146         MOJO_RESULT_INVALID_ARGUMENT,
147         WriteMessageRaw(
148             h_invalid, nullptr, 0, nullptr, 0, MOJO_WRITE_MESSAGE_FLAG_NONE));
149     char buffer[10] = {0};
150     EXPECT_EQ(MOJO_RESULT_INVALID_ARGUMENT,
151               WriteMessageRaw(h_invalid,
152                               buffer,
153                               sizeof(buffer),
154                               nullptr,
155                               0,
156                               MOJO_WRITE_MESSAGE_FLAG_NONE));
157     EXPECT_EQ(MOJO_RESULT_INVALID_ARGUMENT,
158               ReadMessageRaw(h_invalid,
159                              nullptr,
160                              nullptr,
161                              nullptr,
162                              nullptr,
163                              MOJO_READ_MESSAGE_FLAG_NONE));
164     uint32_t buffer_size = static_cast<uint32_t>(sizeof(buffer));
165     EXPECT_EQ(MOJO_RESULT_INVALID_ARGUMENT,
166               ReadMessageRaw(h_invalid,
167                              buffer,
168                              &buffer_size,
169                              nullptr,
170                              nullptr,
171                              MOJO_READ_MESSAGE_FLAG_NONE));
172 
173     // Basic tests of waiting and closing.
174     MojoHandle hv0 = kInvalidHandleValue;
175     {
176       ScopedMessagePipeHandle h0;
177       ScopedMessagePipeHandle h1;
178       EXPECT_FALSE(h0.get().is_valid());
179       EXPECT_FALSE(h1.get().is_valid());
180 
181       CreateMessagePipe(nullptr, &h0, &h1);
182       EXPECT_TRUE(h0.get().is_valid());
183       EXPECT_TRUE(h1.get().is_valid());
184       EXPECT_NE(h0.get().value(), h1.get().value());
185       // Save the handle values, so we can check that things got closed
186       // correctly.
187       hv0 = h0.get().value();
188       MojoHandle hv1 = h1.get().value();
189       MojoHandleSignalsState state;
190 
191       EXPECT_EQ(MOJO_RESULT_DEADLINE_EXCEEDED,
192                 Wait(h0.get(), MOJO_HANDLE_SIGNAL_READABLE, 0, &state));
193 
194       EXPECT_EQ(MOJO_HANDLE_SIGNAL_WRITABLE, state.satisfied_signals);
195       EXPECT_EQ(kSignalAll, state.satisfiable_signals);
196 
197       std::vector<Handle> wh;
198       wh.push_back(h0.get());
199       wh.push_back(h1.get());
200       std::vector<MojoHandleSignals> sigs;
201       sigs.push_back(MOJO_HANDLE_SIGNAL_READABLE);
202       sigs.push_back(MOJO_HANDLE_SIGNAL_WRITABLE);
203       std::vector<MojoHandleSignalsState> states(sigs.size());
204       WaitManyResult wait_many_result = WaitMany(wh, sigs, 1000, &states);
205       EXPECT_EQ(MOJO_RESULT_OK, wait_many_result.result);
206       EXPECT_EQ(1u, wait_many_result.index);
207       EXPECT_TRUE(wait_many_result.IsIndexValid());
208       EXPECT_TRUE(wait_many_result.AreSignalsStatesValid());
209       EXPECT_EQ(MOJO_HANDLE_SIGNAL_WRITABLE, states[0].satisfied_signals);
210       EXPECT_EQ(kSignalAll, states[0].satisfiable_signals);
211       EXPECT_EQ(MOJO_HANDLE_SIGNAL_WRITABLE, states[1].satisfied_signals);
212       EXPECT_EQ(kSignalAll, states[1].satisfiable_signals);
213 
214       // Test closing |h1| explicitly.
215       Close(std::move(h1));
216       EXPECT_FALSE(h1.get().is_valid());
217 
218       // Make sure |h1| is closed.
219       EXPECT_EQ(MOJO_RESULT_INVALID_ARGUMENT,
220                 Wait(Handle(hv1), ~MOJO_HANDLE_SIGNAL_NONE,
221                      MOJO_DEADLINE_INDEFINITE, nullptr));
222 
223       EXPECT_EQ(MOJO_RESULT_FAILED_PRECONDITION,
224                 Wait(h0.get(), MOJO_HANDLE_SIGNAL_READABLE,
225                      MOJO_DEADLINE_INDEFINITE, &state));
226 
227       EXPECT_EQ(MOJO_HANDLE_SIGNAL_PEER_CLOSED, state.satisfied_signals);
228       EXPECT_EQ(MOJO_HANDLE_SIGNAL_PEER_CLOSED, state.satisfiable_signals);
229     }
230     // |hv0| should have been closed when |h0| went out of scope, so this close
231     // should fail.
232     EXPECT_EQ(MOJO_RESULT_INVALID_ARGUMENT, MojoClose(hv0));
233 
234     // Actually test writing/reading messages.
235     {
236       ScopedMessagePipeHandle h0;
237       ScopedMessagePipeHandle h1;
238       CreateMessagePipe(nullptr, &h0, &h1);
239 
240       const char kHello[] = "hello";
241       const uint32_t kHelloSize = static_cast<uint32_t>(sizeof(kHello));
242       EXPECT_EQ(MOJO_RESULT_OK,
243                 WriteMessageRaw(h0.get(),
244                                 kHello,
245                                 kHelloSize,
246                                 nullptr,
247                                 0,
248                                 MOJO_WRITE_MESSAGE_FLAG_NONE));
249 
250       MojoHandleSignalsState state;
251       EXPECT_EQ(MOJO_RESULT_OK, Wait(h1.get(), MOJO_HANDLE_SIGNAL_READABLE,
252                                      MOJO_DEADLINE_INDEFINITE, &state));
253       EXPECT_EQ(kSignalReadableWritable, state.satisfied_signals);
254       EXPECT_EQ(kSignalAll, state.satisfiable_signals);
255 
256       char buffer[10] = {0};
257       uint32_t buffer_size = static_cast<uint32_t>(sizeof(buffer));
258       EXPECT_EQ(MOJO_RESULT_OK,
259                 ReadMessageRaw(h1.get(),
260                                buffer,
261                                &buffer_size,
262                                nullptr,
263                                nullptr,
264                                MOJO_READ_MESSAGE_FLAG_NONE));
265       EXPECT_EQ(kHelloSize, buffer_size);
266       EXPECT_STREQ(kHello, buffer);
267 
268       // Send a handle over the previously-establish message pipe. Use the
269       // |MessagePipe| wrapper (to test it), which automatically creates a
270       // message pipe.
271       MessagePipe mp;
272 
273       // Write a message to |mp.handle0|, before we send |mp.handle1|.
274       const char kWorld[] = "world!";
275       const uint32_t kWorldSize = static_cast<uint32_t>(sizeof(kWorld));
276       EXPECT_EQ(MOJO_RESULT_OK,
277                 WriteMessageRaw(mp.handle0.get(),
278                                 kWorld,
279                                 kWorldSize,
280                                 nullptr,
281                                 0,
282                                 MOJO_WRITE_MESSAGE_FLAG_NONE));
283 
284       // Send |mp.handle1| over |h1| to |h0|.
285       MojoHandle handles[5];
286       handles[0] = mp.handle1.release().value();
287       EXPECT_NE(kInvalidHandleValue, handles[0]);
288       EXPECT_FALSE(mp.handle1.get().is_valid());
289       uint32_t handles_count = 1;
290       EXPECT_EQ(MOJO_RESULT_OK,
291                 WriteMessageRaw(h1.get(),
292                                 kHello,
293                                 kHelloSize,
294                                 handles,
295                                 handles_count,
296                                 MOJO_WRITE_MESSAGE_FLAG_NONE));
297       // |handles[0]| should actually be invalid now.
298       EXPECT_EQ(MOJO_RESULT_INVALID_ARGUMENT, MojoClose(handles[0]));
299 
300       // Read "hello" and the sent handle.
301       EXPECT_EQ(MOJO_RESULT_OK, Wait(h0.get(), MOJO_HANDLE_SIGNAL_READABLE,
302                                      MOJO_DEADLINE_INDEFINITE, &state));
303       EXPECT_EQ(kSignalReadableWritable, state.satisfied_signals);
304       EXPECT_EQ(kSignalAll, state.satisfiable_signals);
305 
306       memset(buffer, 0, sizeof(buffer));
307       buffer_size = static_cast<uint32_t>(sizeof(buffer));
308       for (size_t i = 0; i < arraysize(handles); i++)
309         handles[i] = kInvalidHandleValue;
310       handles_count = static_cast<uint32_t>(arraysize(handles));
311       EXPECT_EQ(MOJO_RESULT_OK,
312                 ReadMessageRaw(h0.get(),
313                                buffer,
314                                &buffer_size,
315                                handles,
316                                &handles_count,
317                                MOJO_READ_MESSAGE_FLAG_NONE));
318       EXPECT_EQ(kHelloSize, buffer_size);
319       EXPECT_STREQ(kHello, buffer);
320       EXPECT_EQ(1u, handles_count);
321       EXPECT_NE(kInvalidHandleValue, handles[0]);
322 
323       // Read from the sent/received handle.
324       mp.handle1.reset(MessagePipeHandle(handles[0]));
325       // Save |handles[0]| to check that it gets properly closed.
326       hv0 = handles[0];
327 
328       EXPECT_EQ(MOJO_RESULT_OK,
329                 Wait(mp.handle1.get(), MOJO_HANDLE_SIGNAL_READABLE,
330                      MOJO_DEADLINE_INDEFINITE, &state));
331       EXPECT_EQ(kSignalReadableWritable, state.satisfied_signals);
332       EXPECT_EQ(kSignalAll, state.satisfiable_signals);
333 
334       memset(buffer, 0, sizeof(buffer));
335       buffer_size = static_cast<uint32_t>(sizeof(buffer));
336       for (size_t i = 0; i < arraysize(handles); i++)
337         handles[i] = kInvalidHandleValue;
338       handles_count = static_cast<uint32_t>(arraysize(handles));
339       EXPECT_EQ(MOJO_RESULT_OK,
340                 ReadMessageRaw(mp.handle1.get(),
341                                buffer,
342                                &buffer_size,
343                                handles,
344                                &handles_count,
345                                MOJO_READ_MESSAGE_FLAG_NONE));
346       EXPECT_EQ(kWorldSize, buffer_size);
347       EXPECT_STREQ(kWorld, buffer);
348       EXPECT_EQ(0u, handles_count);
349     }
350     EXPECT_EQ(MOJO_RESULT_INVALID_ARGUMENT, MojoClose(hv0));
351   }
352 
353   // TODO(vtl): Test |CloseRaw()|.
354   // TODO(vtl): Test |reset()| more thoroughly?
355 }
356 
TEST(CoreCppTest,TearDownWithMessagesEnqueued)357 TEST(CoreCppTest, TearDownWithMessagesEnqueued) {
358   // Tear down a message pipe which still has a message enqueued, with the
359   // message also having a valid message pipe handle.
360   {
361     ScopedMessagePipeHandle h0;
362     ScopedMessagePipeHandle h1;
363     CreateMessagePipe(nullptr, &h0, &h1);
364 
365     // Send a handle over the previously-establish message pipe.
366     ScopedMessagePipeHandle h2;
367     ScopedMessagePipeHandle h3;
368     if (CreateMessagePipe(nullptr, &h2, &h3) != MOJO_RESULT_OK)
369       CreateMessagePipe(nullptr, &h2, &h3);  // Must be old EDK.
370 
371     // Write a message to |h2|, before we send |h3|.
372     const char kWorld[] = "world!";
373     const uint32_t kWorldSize = static_cast<uint32_t>(sizeof(kWorld));
374     EXPECT_EQ(MOJO_RESULT_OK,
375               WriteMessageRaw(h2.get(),
376                               kWorld,
377                               kWorldSize,
378                               nullptr,
379                               0,
380                               MOJO_WRITE_MESSAGE_FLAG_NONE));
381     // And also a message to |h3|.
382     EXPECT_EQ(MOJO_RESULT_OK,
383               WriteMessageRaw(h3.get(),
384                               kWorld,
385                               kWorldSize,
386                               nullptr,
387                               0,
388                               MOJO_WRITE_MESSAGE_FLAG_NONE));
389 
390     // Send |h3| over |h1| to |h0|.
391     const char kHello[] = "hello";
392     const uint32_t kHelloSize = static_cast<uint32_t>(sizeof(kHello));
393     MojoHandle h3_value;
394     h3_value = h3.release().value();
395     EXPECT_NE(kInvalidHandleValue, h3_value);
396     EXPECT_FALSE(h3.get().is_valid());
397     EXPECT_EQ(MOJO_RESULT_OK,
398               WriteMessageRaw(h1.get(),
399                               kHello,
400                               kHelloSize,
401                               &h3_value,
402                               1,
403                               MOJO_WRITE_MESSAGE_FLAG_NONE));
404     // |h3_value| should actually be invalid now.
405     EXPECT_EQ(MOJO_RESULT_INVALID_ARGUMENT, MojoClose(h3_value));
406 
407     EXPECT_EQ(MOJO_RESULT_OK, MojoClose(h0.release().value()));
408     EXPECT_EQ(MOJO_RESULT_OK, MojoClose(h1.release().value()));
409     EXPECT_EQ(MOJO_RESULT_OK, MojoClose(h2.release().value()));
410   }
411 
412   // Do this in a different order: make the enqueued message pipe handle only
413   // half-alive.
414   {
415     ScopedMessagePipeHandle h0;
416     ScopedMessagePipeHandle h1;
417     CreateMessagePipe(nullptr, &h0, &h1);
418 
419     // Send a handle over the previously-establish message pipe.
420     ScopedMessagePipeHandle h2;
421     ScopedMessagePipeHandle h3;
422     if (CreateMessagePipe(nullptr, &h2, &h3) != MOJO_RESULT_OK)
423       CreateMessagePipe(nullptr, &h2, &h3);  // Must be old EDK.
424 
425     // Write a message to |h2|, before we send |h3|.
426     const char kWorld[] = "world!";
427     const uint32_t kWorldSize = static_cast<uint32_t>(sizeof(kWorld));
428     EXPECT_EQ(MOJO_RESULT_OK,
429               WriteMessageRaw(h2.get(),
430                               kWorld,
431                               kWorldSize,
432                               nullptr,
433                               0,
434                               MOJO_WRITE_MESSAGE_FLAG_NONE));
435     // And also a message to |h3|.
436     EXPECT_EQ(MOJO_RESULT_OK,
437               WriteMessageRaw(h3.get(),
438                               kWorld,
439                               kWorldSize,
440                               nullptr,
441                               0,
442                               MOJO_WRITE_MESSAGE_FLAG_NONE));
443 
444     // Send |h3| over |h1| to |h0|.
445     const char kHello[] = "hello";
446     const uint32_t kHelloSize = static_cast<uint32_t>(sizeof(kHello));
447     MojoHandle h3_value;
448     h3_value = h3.release().value();
449     EXPECT_NE(kInvalidHandleValue, h3_value);
450     EXPECT_FALSE(h3.get().is_valid());
451     EXPECT_EQ(MOJO_RESULT_OK,
452               WriteMessageRaw(h1.get(),
453                               kHello,
454                               kHelloSize,
455                               &h3_value,
456                               1,
457                               MOJO_WRITE_MESSAGE_FLAG_NONE));
458     // |h3_value| should actually be invalid now.
459     EXPECT_EQ(MOJO_RESULT_INVALID_ARGUMENT, MojoClose(h3_value));
460 
461     EXPECT_EQ(MOJO_RESULT_OK, MojoClose(h2.release().value()));
462     EXPECT_EQ(MOJO_RESULT_OK, MojoClose(h0.release().value()));
463     EXPECT_EQ(MOJO_RESULT_OK, MojoClose(h1.release().value()));
464   }
465 }
466 
TEST(CoreCppTest,ScopedHandleMoveCtor)467 TEST(CoreCppTest, ScopedHandleMoveCtor) {
468   ScopedSharedBufferHandle buffer1 = SharedBufferHandle::Create(1024);
469   EXPECT_TRUE(buffer1.is_valid());
470 
471   ScopedSharedBufferHandle buffer2 = SharedBufferHandle::Create(1024);
472   EXPECT_TRUE(buffer2.is_valid());
473 
474   // If this fails to close buffer1, ScopedHandleBase::CloseIfNecessary() will
475   // assert.
476   buffer1 = std::move(buffer2);
477 
478   EXPECT_TRUE(buffer1.is_valid());
479   EXPECT_FALSE(buffer2.is_valid());
480 }
481 
TEST(CoreCppTest,BasicSharedBuffer)482 TEST(CoreCppTest, BasicSharedBuffer) {
483   ScopedSharedBufferHandle h0 = SharedBufferHandle::Create(100);
484   ASSERT_TRUE(h0.is_valid());
485 
486   // Map everything.
487   ScopedSharedBufferMapping mapping = h0->Map(100);
488   ASSERT_TRUE(mapping);
489   static_cast<char*>(mapping.get())[50] = 'x';
490 
491   // Duplicate |h0| to |h1|.
492   ScopedSharedBufferHandle h1 =
493       h0->Clone(SharedBufferHandle::AccessMode::READ_ONLY);
494   ASSERT_TRUE(h1.is_valid());
495 
496   // Close |h0|.
497   h0.reset();
498 
499   // The mapping should still be good.
500   static_cast<char*>(mapping.get())[51] = 'y';
501 
502   // Unmap it.
503   mapping.reset();
504 
505   // Map half of |h1|.
506   mapping = h1->MapAtOffset(50, 50);
507   ASSERT_TRUE(mapping);
508 
509   // It should have what we wrote.
510   EXPECT_EQ('x', static_cast<char*>(mapping.get())[0]);
511   EXPECT_EQ('y', static_cast<char*>(mapping.get())[1]);
512 
513   // Unmap it.
514   mapping.reset();
515   h1.reset();
516 
517   // Creating a 1 EB shared buffer should fail without crashing.
518   EXPECT_FALSE(SharedBufferHandle::Create(1ULL << 60).is_valid());
519 }
520 
521 // TODO(vtl): Write data pipe tests.
522 
523 }  // namespace
524 }  // namespace mojo
525