base/memory/shared_memory_unittest.cc

   1 // Copyright (c) 2012 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 #include "base/basictypes.h"
   6 #include "base/memory/scoped_ptr.h"
   7 #include "base/memory/shared_memory.h"
   8 #include "base/process/kill.h"
   9 #include "base/rand_util.h"
  10 #include "base/strings/string_number_conversions.h"
  11 #include "base/sys_info.h"
  12 #include "base/test/multiprocess_test.h"
  13 #include "base/threading/platform_thread.h"
  14 #include "base/time/time.h"
  15 #include "testing/gtest/include/gtest/gtest.h"
  16 #include "testing/multiprocess_func_list.h"
  17
  18 #if defined(OS_MACOSX)
  19 #include "base/mac/scoped_nsautorelease_pool.h"
  20 #endif
  21
  22 #if defined(OS_POSIX)
  23 #include <errno.h>
  24 #include <fcntl.h>
  25 #include <sys/mman.h>
  26 #include <sys/stat.h>
  27 #include <sys/types.h>
  28 #include <unistd.h>
  29 #endif
  30
  31 #if defined(OS_WIN)
  32 #include "base/win/scoped_handle.h"
  33 #endif
  34
  35 static const int kNumThreads = 5;
  36 #if !defined(OS_IOS)  // iOS does not allow multiple processes.
  37 static const int kNumTasks = 5;
  38 #endif
  39
  40 namespace base {
  41
  42 namespace {
  43
  44 // Each thread will open the shared memory.  Each thread will take a different 4
  45 // byte int pointer, and keep changing it, with some small pauses in between.
  46 // Verify that each thread's value in the shared memory is always correct.
  47 class MultipleThreadMain : public PlatformThread::Delegate {
  48  public:
  49   explicit MultipleThreadMain(int16 id) : id_(id) {}
  50   ~MultipleThreadMain() override {}
  51
  52   static void CleanUp() {
  53     SharedMemory memory;
  54     memory.Delete(s_test_name_);
  55   }
  56
  57   // PlatformThread::Delegate interface.
  58   void ThreadMain() override {
  59 #if defined(OS_MACOSX)
  60     mac::ScopedNSAutoreleasePool pool;
  61 #endif
  62     const uint32 kDataSize = 1024;
  63     SharedMemory memory;
  64     bool rv = memory.CreateNamedDeprecated(s_test_name_, true, kDataSize);
  65     EXPECT_TRUE(rv);
  66     rv = memory.Map(kDataSize);
  67     EXPECT_TRUE(rv);
  68     int *ptr = static_cast<int*>(memory.memory()) + id_;
  69     EXPECT_EQ(0, *ptr);
  70
  71     for (int idx = 0; idx < 100; idx++) {
  72       *ptr = idx;
  73       PlatformThread::Sleep(base::TimeDelta::FromMilliseconds(1));
  74       EXPECT_EQ(*ptr, idx);
  75     }
  76     // Reset back to 0 for the next test that uses the same name.
  77     *ptr = 0;
  78
  79     memory.Close();
  80   }
  81
  82  private:
  83   int16 id_;
  84
  85   static const char* const s_test_name_;
  86
  87   DISALLOW_COPY_AND_ASSIGN(MultipleThreadMain);
  88 };
  89
  90 const char* const MultipleThreadMain::s_test_name_ =
  91     "SharedMemoryOpenThreadTest";
  92
  93 // TODO(port):
  94 // This test requires the ability to pass file descriptors between processes.
  95 // We haven't done that yet in Chrome for POSIX.
  96 #if defined(OS_WIN)
  97 // Each thread will open the shared memory.  Each thread will take the memory,
  98 // and keep changing it while trying to lock it, with some small pauses in
  99 // between. Verify that each thread's value in the shared memory is always
 100 // correct.
 101 class MultipleLockThread : public PlatformThread::Delegate {
 102  public:
 103   explicit MultipleLockThread(int id) : id_(id) {}
 104   virtual ~MultipleLockThread() {}
 105
 106   // PlatformThread::Delegate interface.
 107   virtual void ThreadMain() override {
 108     const uint32 kDataSize = sizeof(int);
 109     SharedMemoryHandle handle = NULL;
 110     {
 111       SharedMemory memory1;
 112       EXPECT_TRUE(memory1.CreateNamedDeprecated(
 113           "SharedMemoryMultipleLockThreadTest", true, kDataSize));
 114       EXPECT_TRUE(memory1.ShareToProcess(GetCurrentProcess(), &handle));
 115       // TODO(paulg): Implement this once we have a posix version of
 116       // SharedMemory::ShareToProcess.
 117       EXPECT_TRUE(true);
 118     }
 119
 120     SharedMemory memory2(handle, false);
 121     EXPECT_TRUE(memory2.Map(kDataSize));
 122     volatile int* const ptr = static_cast<int*>(memory2.memory());
 123
 124     for (int idx = 0; idx < 20; idx++) {
 125       memory2.LockDeprecated();
 126       int i = (id_ << 16) + idx;
 127       *ptr = i;
 128       PlatformThread::Sleep(TimeDelta::FromMilliseconds(1));
 129       EXPECT_EQ(*ptr, i);
 130       memory2.UnlockDeprecated();
 131     }
 132
 133     memory2.Close();
 134   }
 135
 136  private:
 137   int id_;
 138
 139   DISALLOW_COPY_AND_ASSIGN(MultipleLockThread);
 140 };
 141 #endif
 142
 143 }  // namespace
 144
 145 // Android doesn't support SharedMemory::Open/Delete/
 146 // CreateNamedDeprecated(openExisting=true)
 147 #if !defined(OS_ANDROID)
 148 TEST(SharedMemoryTest, OpenClose) {
 149   const uint32 kDataSize = 1024;
 150   std::string test_name = "SharedMemoryOpenCloseTest";
 151
 152   // Open two handles to a memory segment, confirm that they are mapped
 153   // separately yet point to the same space.
 154   SharedMemory memory1;
 155   bool rv = memory1.Delete(test_name);
 156   EXPECT_TRUE(rv);
 157   rv = memory1.Delete(test_name);
 158   EXPECT_TRUE(rv);
 159   rv = memory1.Open(test_name, false);
 160   EXPECT_FALSE(rv);
 161   rv = memory1.CreateNamedDeprecated(test_name, false, kDataSize);
 162   EXPECT_TRUE(rv);
 163   rv = memory1.Map(kDataSize);
 164   EXPECT_TRUE(rv);
 165   SharedMemory memory2;
 166   rv = memory2.Open(test_name, false);
 167   EXPECT_TRUE(rv);
 168   rv = memory2.Map(kDataSize);
 169   EXPECT_TRUE(rv);
 170   EXPECT_NE(memory1.memory(), memory2.memory());  // Compare the pointers.
 171
 172   // Make sure we don't segfault. (it actually happened!)
 173   ASSERT_NE(memory1.memory(), static_cast<void*>(NULL));
 174   ASSERT_NE(memory2.memory(), static_cast<void*>(NULL));
 175
 176   // Write data to the first memory segment, verify contents of second.
 177   memset(memory1.memory(), '1', kDataSize);
 178   EXPECT_EQ(memcmp(memory1.memory(), memory2.memory(), kDataSize), 0);
 179
 180   // Close the first memory segment, and verify the second has the right data.
 181   memory1.Close();
 182   char *start_ptr = static_cast<char *>(memory2.memory());
 183   char *end_ptr = start_ptr + kDataSize;
 184   for (char* ptr = start_ptr; ptr < end_ptr; ptr++)
 185     EXPECT_EQ(*ptr, '1');
 186
 187   // Close the second memory segment.
 188   memory2.Close();
 189
 190   rv = memory1.Delete(test_name);
 191   EXPECT_TRUE(rv);
 192   rv = memory2.Delete(test_name);
 193   EXPECT_TRUE(rv);
 194 }
 195
 196 TEST(SharedMemoryTest, OpenExclusive) {
 197   const uint32 kDataSize = 1024;
 198   const uint32 kDataSize2 = 2048;
 199   std::ostringstream test_name_stream;
 200   test_name_stream << "SharedMemoryOpenExclusiveTest."
 201                    << Time::Now().ToDoubleT();
 202   std::string test_name = test_name_stream.str();
 203
 204   // Open two handles to a memory segment and check that
 205   // open_existing_deprecated works as expected.
 206   SharedMemory memory1;
 207   bool rv = memory1.CreateNamedDeprecated(test_name, false, kDataSize);
 208   EXPECT_TRUE(rv);
 209
 210   // Memory1 knows it's size because it created it.
 211   EXPECT_EQ(memory1.requested_size(), kDataSize);
 212
 213   rv = memory1.Map(kDataSize);
 214   EXPECT_TRUE(rv);
 215
 216   // The mapped memory1 must be at least the size we asked for.
 217   EXPECT_GE(memory1.mapped_size(), kDataSize);
 218
 219   // The mapped memory1 shouldn't exceed rounding for allocation granularity.
 220   EXPECT_LT(memory1.mapped_size(),
 221             kDataSize + base::SysInfo::VMAllocationGranularity());
 222
 223   memset(memory1.memory(), 'G', kDataSize);
 224
 225   SharedMemory memory2;
 226   // Should not be able to create if openExisting is false.
 227   rv = memory2.CreateNamedDeprecated(test_name, false, kDataSize2);
 228   EXPECT_FALSE(rv);
 229
 230   // Should be able to create with openExisting true.
 231   rv = memory2.CreateNamedDeprecated(test_name, true, kDataSize2);
 232   EXPECT_TRUE(rv);
 233
 234   // Memory2 shouldn't know the size because we didn't create it.
 235   EXPECT_EQ(memory2.requested_size(), 0U);
 236
 237   // We should be able to map the original size.
 238   rv = memory2.Map(kDataSize);
 239   EXPECT_TRUE(rv);
 240
 241   // The mapped memory2 must be at least the size of the original.
 242   EXPECT_GE(memory2.mapped_size(), kDataSize);
 243
 244   // The mapped memory2 shouldn't exceed rounding for allocation granularity.
 245   EXPECT_LT(memory2.mapped_size(),
 246             kDataSize2 + base::SysInfo::VMAllocationGranularity());
 247
 248   // Verify that opening memory2 didn't truncate or delete memory 1.
 249   char *start_ptr = static_cast<char *>(memory2.memory());
 250   char *end_ptr = start_ptr + kDataSize;
 251   for (char* ptr = start_ptr; ptr < end_ptr; ptr++) {
 252     EXPECT_EQ(*ptr, 'G');
 253   }
 254
 255   memory1.Close();
 256   memory2.Close();
 257
 258   rv = memory1.Delete(test_name);
 259   EXPECT_TRUE(rv);
 260 }
 261 #endif
 262
 263 // Check that memory is still mapped after its closed.
 264 TEST(SharedMemoryTest, CloseNoUnmap) {
 265   const size_t kDataSize = 4096;
 266
 267   SharedMemory memory;
 268   ASSERT_TRUE(memory.CreateAndMapAnonymous(kDataSize));
 269   char* ptr = static_cast<char*>(memory.memory());
 270   ASSERT_NE(ptr, static_cast<void*>(NULL));
 271   memset(ptr, 'G', kDataSize);
 272
 273   memory.Close();
 274
 275   EXPECT_EQ(ptr, memory.memory());
 276   EXPECT_EQ(SharedMemory::NULLHandle(), memory.handle());
 277
 278   for (size_t i = 0; i < kDataSize; i++) {
 279     EXPECT_EQ('G', ptr[i]);
 280   }
 281
 282   memory.Unmap();
 283   EXPECT_EQ(nullptr, memory.memory());
 284 }
 285
 286 // Create a set of N threads to each open a shared memory segment and write to
 287 // it. Verify that they are always reading/writing consistent data.
 288 TEST(SharedMemoryTest, MultipleThreads) {
 289   MultipleThreadMain::CleanUp();
 290   // On POSIX we have a problem when 2 threads try to create the shmem
 291   // (a file) at exactly the same time, since create both creates the
 292   // file and zerofills it.  We solve the problem for this unit test
 293   // (make it not flaky) by starting with 1 thread, then
 294   // intentionally don't clean up its shmem before running with
 295   // kNumThreads.
 296
 297   int threadcounts[] = { 1, kNumThreads };
 298   for (size_t i = 0; i < arraysize(threadcounts); i++) {
 299     int numthreads = threadcounts[i];
 300     scoped_ptr<PlatformThreadHandle[]> thread_handles;
 301     scoped_ptr<MultipleThreadMain*[]> thread_delegates;
 302
 303     thread_handles.reset(new PlatformThreadHandle[numthreads]);
 304     thread_delegates.reset(new MultipleThreadMain*[numthreads]);
 305
 306     // Spawn the threads.
 307     for (int16 index = 0; index < numthreads; index++) {
 308       PlatformThreadHandle pth;
 309       thread_delegates[index] = new MultipleThreadMain(index);
 310       EXPECT_TRUE(PlatformThread::Create(0, thread_delegates[index], &pth));
 311       thread_handles[index] = pth;
 312     }
 313
 314     // Wait for the threads to finish.
 315     for (int index = 0; index < numthreads; index++) {
 316       PlatformThread::Join(thread_handles[index]);
 317       delete thread_delegates[index];
 318     }
 319   }
 320   MultipleThreadMain::CleanUp();
 321 }
 322
 323 // TODO(port): this test requires the MultipleLockThread class
 324 // (defined above), which requires the ability to pass file
 325 // descriptors between processes.  We haven't done that yet in Chrome
 326 // for POSIX.
 327 #if defined(OS_WIN)
 328 // Create a set of threads to each open a shared memory segment and write to it
 329 // with the lock held. Verify that they are always reading/writing consistent
 330 // data.
 331 TEST(SharedMemoryTest, Lock) {
 332   PlatformThreadHandle thread_handles[kNumThreads];
 333   MultipleLockThread* thread_delegates[kNumThreads];
 334
 335   // Spawn the threads.
 336   for (int index = 0; index < kNumThreads; ++index) {
 337     PlatformThreadHandle pth;
 338     thread_delegates[index] = new MultipleLockThread(index);
 339     EXPECT_TRUE(PlatformThread::Create(0, thread_delegates[index], &pth));
 340     thread_handles[index] = pth;
 341   }
 342
 343   // Wait for the threads to finish.
 344   for (int index = 0; index < kNumThreads; ++index) {
 345     PlatformThread::Join(thread_handles[index]);
 346     delete thread_delegates[index];
 347   }
 348 }
 349 #endif
 350
 351 // Allocate private (unique) shared memory with an empty string for a
 352 // name.  Make sure several of them don't point to the same thing as
 353 // we might expect if the names are equal.
 354 TEST(SharedMemoryTest, AnonymousPrivate) {
 355   int i, j;
 356   int count = 4;
 357   bool rv;
 358   const uint32 kDataSize = 8192;
 359
 360   scoped_ptr<SharedMemory[]> memories(new SharedMemory[count]);
 361   scoped_ptr<int*[]> pointers(new int*[count]);
 362   ASSERT_TRUE(memories.get());
 363   ASSERT_TRUE(pointers.get());
 364
 365   for (i = 0; i < count; i++) {
 366     rv = memories[i].CreateAndMapAnonymous(kDataSize);
 367     EXPECT_TRUE(rv);
 368     int *ptr = static_cast<int*>(memories[i].memory());
 369     EXPECT_TRUE(ptr);
 370     pointers[i] = ptr;
 371   }
 372
 373   for (i = 0; i < count; i++) {
 374     // zero out the first int in each except for i; for that one, make it 100.
 375     for (j = 0; j < count; j++) {
 376       if (i == j)
 377         pointers[j][0] = 100;
 378       else
 379         pointers[j][0] = 0;
 380     }
 381     // make sure there is no bleeding of the 100 into the other pointers
 382     for (j = 0; j < count; j++) {
 383       if (i == j)
 384         EXPECT_EQ(100, pointers[j][0]);
 385       else
 386         EXPECT_EQ(0, pointers[j][0]);
 387     }
 388   }
 389
 390   for (int i = 0; i < count; i++) {
 391     memories[i].Close();
 392   }
 393 }
 394
 395 TEST(SharedMemoryTest, ShareReadOnly) {
 396   StringPiece contents = "Hello World";
 397
 398   SharedMemory writable_shmem;
 399   SharedMemoryCreateOptions options;
 400   options.size = contents.size();
 401   options.share_read_only = true;
 402   ASSERT_TRUE(writable_shmem.Create(options));
 403   ASSERT_TRUE(writable_shmem.Map(options.size));
 404   memcpy(writable_shmem.memory(), contents.data(), contents.size());
 405   EXPECT_TRUE(writable_shmem.Unmap());
 406
 407   SharedMemoryHandle readonly_handle;
 408   ASSERT_TRUE(writable_shmem.ShareReadOnlyToProcess(GetCurrentProcessHandle(),
 409                                                     &readonly_handle));
 410   SharedMemory readonly_shmem(readonly_handle, /*readonly=*/true);
 411
 412   ASSERT_TRUE(readonly_shmem.Map(contents.size()));
 413   EXPECT_EQ(contents,
 414             StringPiece(static_cast<const char*>(readonly_shmem.memory()),
 415                         contents.size()));
 416   EXPECT_TRUE(readonly_shmem.Unmap());
 417
 418   // Make sure the writable instance is still writable.
 419   ASSERT_TRUE(writable_shmem.Map(contents.size()));
 420   StringPiece new_contents = "Goodbye";
 421   memcpy(writable_shmem.memory(), new_contents.data(), new_contents.size());
 422   EXPECT_EQ(new_contents,
 423             StringPiece(static_cast<const char*>(writable_shmem.memory()),
 424                         new_contents.size()));
 425
 426   // We'd like to check that if we send the read-only segment to another
 427   // process, then that other process can't reopen it read/write.  (Since that
 428   // would be a security hole.)  Setting up multiple processes is hard in a
 429   // unittest, so this test checks that the *current* process can't reopen the
 430   // segment read/write.  I think the test here is stronger than we actually
 431   // care about, but there's a remote possibility that sending a file over a
 432   // pipe would transform it into read/write.
 433   SharedMemoryHandle handle = readonly_shmem.handle();
 434
 435 #if defined(OS_ANDROID)
 436   // The "read-only" handle is still writable on Android:
 437   // http://crbug.com/320865
 438   (void)handle;
 439 #elif defined(OS_POSIX)
 440   EXPECT_EQ(O_RDONLY, fcntl(handle.fd, F_GETFL) & O_ACCMODE)
 441       << "The descriptor itself should be read-only.";
 442
 443   errno = 0;
 444   void* writable = mmap(
 445       NULL, contents.size(), PROT_READ | PROT_WRITE, MAP_SHARED, handle.fd, 0);
 446   int mmap_errno = errno;
 447   EXPECT_EQ(MAP_FAILED, writable)
 448       << "It shouldn't be possible to re-mmap the descriptor writable.";
 449   EXPECT_EQ(EACCES, mmap_errno) << strerror(mmap_errno);
 450   if (writable != MAP_FAILED)
 451     EXPECT_EQ(0, munmap(writable, readonly_shmem.mapped_size()));
 452
 453 #elif defined(OS_WIN)
 454   EXPECT_EQ(NULL, MapViewOfFile(handle, FILE_MAP_WRITE, 0, 0, 0))
 455       << "Shouldn't be able to map memory writable.";
 456
 457   HANDLE temp_handle;
 458   BOOL rv = ::DuplicateHandle(GetCurrentProcess(),
 459                               handle,
 460                               GetCurrentProcess(),
 461                               &temp_handle,
 462                               FILE_MAP_ALL_ACCESS,
 463                               false,
 464                               0);
 465   EXPECT_EQ(FALSE, rv)
 466       << "Shouldn't be able to duplicate the handle into a writable one.";
 467   if (rv)
 468     base::win::ScopedHandle writable_handle(temp_handle);
 469   rv = ::DuplicateHandle(GetCurrentProcess(),
 470                          handle,
 471                          GetCurrentProcess(),
 472                          &temp_handle,
 473                          FILE_MAP_READ,
 474                          false,
 475                          0);
 476   EXPECT_EQ(TRUE, rv)
 477       << "Should be able to duplicate the handle into a readable one.";
 478   if (rv)
 479     base::win::ScopedHandle writable_handle(temp_handle);
 480 #else
 481 #error Unexpected platform; write a test that tries to make 'handle' writable.
 482 #endif  // defined(OS_POSIX) || defined(OS_WIN)
 483 }
 484
 485 TEST(SharedMemoryTest, ShareToSelf) {
 486   StringPiece contents = "Hello World";
 487
 488   SharedMemory shmem;
 489   ASSERT_TRUE(shmem.CreateAndMapAnonymous(contents.size()));
 490   memcpy(shmem.memory(), contents.data(), contents.size());
 491   EXPECT_TRUE(shmem.Unmap());
 492
 493   SharedMemoryHandle shared_handle;
 494   ASSERT_TRUE(shmem.ShareToProcess(GetCurrentProcessHandle(), &shared_handle));
 495   SharedMemory shared(shared_handle, /*readonly=*/false);
 496
 497   ASSERT_TRUE(shared.Map(contents.size()));
 498   EXPECT_EQ(
 499       contents,
 500       StringPiece(static_cast<const char*>(shared.memory()), contents.size()));
 501
 502   ASSERT_TRUE(shmem.ShareToProcess(GetCurrentProcessHandle(), &shared_handle));
 503   SharedMemory readonly(shared_handle, /*readonly=*/true);
 504
 505   ASSERT_TRUE(readonly.Map(contents.size()));
 506   EXPECT_EQ(contents,
 507             StringPiece(static_cast<const char*>(readonly.memory()),
 508                         contents.size()));
 509 }
 510
 511 TEST(SharedMemoryTest, MapAt) {
 512   ASSERT_TRUE(SysInfo::VMAllocationGranularity() >= sizeof(uint32));
 513   const size_t kCount = SysInfo::VMAllocationGranularity();
 514   const size_t kDataSize = kCount * sizeof(uint32);
 515
 516   SharedMemory memory;
 517   ASSERT_TRUE(memory.CreateAndMapAnonymous(kDataSize));
 518   uint32* ptr = static_cast<uint32*>(memory.memory());
 519   ASSERT_NE(ptr, static_cast<void*>(NULL));
 520
 521   for (size_t i = 0; i < kCount; ++i) {
 522     ptr[i] = i;
 523   }
 524
 525   memory.Unmap();
 526
 527   off_t offset = SysInfo::VMAllocationGranularity();
 528   ASSERT_TRUE(memory.MapAt(offset, kDataSize - offset));
 529   offset /= sizeof(uint32);
 530   ptr = static_cast<uint32*>(memory.memory());
 531   ASSERT_NE(ptr, static_cast<void*>(NULL));
 532   for (size_t i = offset; i < kCount; ++i) {
 533     EXPECT_EQ(ptr[i - offset], i);
 534   }
 535 }
 536
 537 TEST(SharedMemoryTest, MapTwice) {
 538   const uint32 kDataSize = 1024;
 539   SharedMemory memory;
 540   bool rv = memory.CreateAndMapAnonymous(kDataSize);
 541   EXPECT_TRUE(rv);
 542
 543   void* old_address = memory.memory();
 544
 545   rv = memory.Map(kDataSize);
 546   EXPECT_FALSE(rv);
 547   EXPECT_EQ(old_address, memory.memory());
 548 }
 549
 550 #if defined(OS_POSIX)
 551 // This test is not applicable for iOS (crbug.com/399384).
 552 #if !defined(OS_IOS)
 553 // Create a shared memory object, mmap it, and mprotect it to PROT_EXEC.
 554 TEST(SharedMemoryTest, AnonymousExecutable) {
 555   const uint32 kTestSize = 1 << 16;
 556
 557   SharedMemory shared_memory;
 558   SharedMemoryCreateOptions options;
 559   options.size = kTestSize;
 560   options.executable = true;
 561
 562   EXPECT_TRUE(shared_memory.Create(options));
 563   EXPECT_TRUE(shared_memory.Map(shared_memory.requested_size()));
 564
 565   EXPECT_EQ(0, mprotect(shared_memory.memory(), shared_memory.requested_size(),
 566                         PROT_READ | PROT_EXEC));
 567 }
 568 #endif  // !defined(OS_IOS)
 569
 570 // Android supports a different permission model than POSIX for its "ashmem"
 571 // shared memory implementation. So the tests about file permissions are not
 572 // included on Android.
 573 #if !defined(OS_ANDROID)
 574
 575 // Set a umask and restore the old mask on destruction.
 576 class ScopedUmaskSetter {
 577  public:
 578   explicit ScopedUmaskSetter(mode_t target_mask) {
 579     old_umask_ = umask(target_mask);
 580   }
 581   ~ScopedUmaskSetter() { umask(old_umask_); }
 582  private:
 583   mode_t old_umask_;
 584   DISALLOW_IMPLICIT_CONSTRUCTORS(ScopedUmaskSetter);
 585 };
 586
 587 // Create a shared memory object, check its permissions.
 588 TEST(SharedMemoryTest, FilePermissionsAnonymous) {
 589   const uint32 kTestSize = 1 << 8;
 590
 591   SharedMemory shared_memory;
 592   SharedMemoryCreateOptions options;
 593   options.size = kTestSize;
 594   // Set a file mode creation mask that gives all permissions.
 595   ScopedUmaskSetter permissive_mask(S_IWGRP | S_IWOTH);
 596
 597   EXPECT_TRUE(shared_memory.Create(options));
 598
 599   int shm_fd = shared_memory.handle().fd;
 600   struct stat shm_stat;
 601   EXPECT_EQ(0, fstat(shm_fd, &shm_stat));
 602   // Neither the group, nor others should be able to read the shared memory
 603   // file.
 604   EXPECT_FALSE(shm_stat.st_mode & S_IRWXO);
 605   EXPECT_FALSE(shm_stat.st_mode & S_IRWXG);
 606 }
 607
 608 // Create a shared memory object, check its permissions.
 609 TEST(SharedMemoryTest, FilePermissionsNamed) {
 610   const uint32 kTestSize = 1 << 8;
 611
 612   SharedMemory shared_memory;
 613   SharedMemoryCreateOptions options;
 614   options.size = kTestSize;
 615   std::string shared_mem_name = "shared_perm_test-" + IntToString(getpid()) +
 616       "-" + Uint64ToString(RandUint64());
 617   options.name_deprecated = &shared_mem_name;
 618   // Set a file mode creation mask that gives all permissions.
 619   ScopedUmaskSetter permissive_mask(S_IWGRP | S_IWOTH);
 620
 621   EXPECT_TRUE(shared_memory.Create(options));
 622   // Clean-up the backing file name immediately, we don't need it.
 623   EXPECT_TRUE(shared_memory.Delete(shared_mem_name));
 624
 625   int shm_fd = shared_memory.handle().fd;
 626   struct stat shm_stat;
 627   EXPECT_EQ(0, fstat(shm_fd, &shm_stat));
 628   // Neither the group, nor others should have been able to open the shared
 629   // memory file while its name existed.
 630   EXPECT_FALSE(shm_stat.st_mode & S_IRWXO);
 631   EXPECT_FALSE(shm_stat.st_mode & S_IRWXG);
 632 }
 633 #endif  // !defined(OS_ANDROID)
 634
 635 #endif  // defined(OS_POSIX)
 636
 637 // Map() will return addresses which are aligned to the platform page size, this
 638 // varies from platform to platform though.  Since we'd like to advertise a
 639 // minimum alignment that callers can count on, test for it here.
 640 TEST(SharedMemoryTest, MapMinimumAlignment) {
 641   static const int kDataSize = 8192;
 642
 643   SharedMemory shared_memory;
 644   ASSERT_TRUE(shared_memory.CreateAndMapAnonymous(kDataSize));
 645   EXPECT_EQ(0U, reinterpret_cast<uintptr_t>(
 646       shared_memory.memory()) & (SharedMemory::MAP_MINIMUM_ALIGNMENT - 1));
 647   shared_memory.Close();
 648 }
 649
 650 #if !defined(OS_IOS)  // iOS does not allow multiple processes.
 651
 652 // On POSIX it is especially important we test shmem across processes,
 653 // not just across threads.  But the test is enabled on all platforms.
 654 class SharedMemoryProcessTest : public MultiProcessTest {
 655  public:
 656
 657   static void CleanUp() {
 658     SharedMemory memory;
 659     memory.Delete(s_test_name_);
 660   }
 661
 662   static int TaskTestMain() {
 663     int errors = 0;
 664 #if defined(OS_MACOSX)
 665     mac::ScopedNSAutoreleasePool pool;
 666 #endif
 667     const uint32 kDataSize = 1024;
 668     SharedMemory memory;
 669     bool rv = memory.CreateNamedDeprecated(s_test_name_, true, kDataSize);
 670     EXPECT_TRUE(rv);
 671     if (rv != true)
 672       errors++;
 673     rv = memory.Map(kDataSize);
 674     EXPECT_TRUE(rv);
 675     if (rv != true)
 676       errors++;
 677     int *ptr = static_cast<int*>(memory.memory());
 678
 679     for (int idx = 0; idx < 20; idx++) {
 680       memory.LockDeprecated();
 681       int i = (1 << 16) + idx;
 682       *ptr = i;
 683       PlatformThread::Sleep(TimeDelta::FromMilliseconds(10));
 684       if (*ptr != i)
 685         errors++;
 686       memory.UnlockDeprecated();
 687     }
 688
 689     memory.Close();
 690     return errors;
 691   }
 692
 693  private:
 694   static const char* const s_test_name_;
 695 };
 696
 697 const char* const SharedMemoryProcessTest::s_test_name_ = "MPMem";
 698
 699 TEST_F(SharedMemoryProcessTest, Tasks) {
 700   SharedMemoryProcessTest::CleanUp();
 701
 702   Process processes[kNumTasks];
 703   for (int index = 0; index < kNumTasks; ++index) {
 704     processes[index] = SpawnChild("SharedMemoryTestMain");
 705     ASSERT_TRUE(processes[index].IsValid());
 706   }
 707
 708   int exit_code = 0;
 709   for (int index = 0; index < kNumTasks; ++index) {
 710     EXPECT_TRUE(processes[index].WaitForExit(&exit_code));
 711     EXPECT_EQ(0, exit_code);
 712   }
 713
 714   SharedMemoryProcessTest::CleanUp();
 715 }
 716
 717 MULTIPROCESS_TEST_MAIN(SharedMemoryTestMain) {
 718   return SharedMemoryProcessTest::TaskTestMain();
 719 }
 720
 721 #endif  // !OS_IOS
 722
 723 }  // namespace base