Update //base to chromium 9659b08ea5a34f889dc4166217f438095ddc10d2

base/memory/shared_memory_mac.cc

 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "base/memory/shared_memory.h"
 
-#include <errno.h>
 #include <fcntl.h>
 #include <sys/mman.h>
 #include <sys/stat.h>
-#include <sys/types.h>
 #include <unistd.h>
 
 #include "base/files/file_util.h"
 #include "base/files/scoped_file.h"
-#include "base/lazy_instance.h"
 #include "base/logging.h"
 #include "base/posix/eintr_wrapper.h"
 #include "base/posix/safe_strerror.h"
 #include "base/process/process_metrics.h"
 #include "base/profiler/scoped_tracker.h"
 #include "base/scoped_generic.h"
 #include "base/strings/utf_string_conversions.h"
-#include "base/synchronization/lock.h"
-#include "base/threading/platform_thread.h"
-#include "base/threading/thread_restrictions.h"
 
 #if defined(OS_MACOSX)
 #include "base/mac/foundation_util.h"
 #endif  // OS_MACOSX
 
-#if defined(OS_ANDROID)
-#include "base/os_compat_android.h"
-#include "third_party/ashmem/ashmem.h"
-#endif
-
 namespace base {
 
 namespace {
 
-LazyInstance<Lock>::Leaky g_thread_lock_ = LAZY_INSTANCE_INITIALIZER;
-
 struct ScopedPathUnlinkerTraits {
   static FilePath* InvalidValue() { return nullptr; }
 
   static void Free(FilePath* path) {
     // TODO(erikchen): Remove ScopedTracker below once http://crbug.com/466437
     // is fixed.
     tracked_objects::ScopedTracker tracking_profile(
         FROM_HERE_WITH_EXPLICIT_FUNCTION(
             "466437 SharedMemory::Create::Unlink"));
     if (unlink(path->value().c_str()))
       PLOG(WARNING) << "unlink";
   }
 };
 
 // Unlinks the FilePath when the object is destroyed.
 typedef ScopedGeneric<FilePath*, ScopedPathUnlinkerTraits> ScopedPathUnlinker;
 
-#if !defined(OS_ANDROID)
 // Makes a temporary file, fdopens it, and then unlinks it. |fp| is populated
 // with the fdopened FILE. |readonly_fd| is populated with the opened fd if
 // options.share_read_only is true. |path| is populated with the location of
 // the file before it was unlinked.
 // Returns false if there's an unhandled failure.
 bool CreateAnonymousSharedMemory(const SharedMemoryCreateOptions& options,
                                  ScopedFILE* fp,
                                  ScopedFD* readonly_fd,
                                  FilePath* path) {
   // It doesn't make sense to have a open-existing private piece of shmem
@@ skipping 28 matching lines @@
       readonly_fd->reset(HANDLE_EINTR(open(path->value().c_str(), O_RDONLY)));
       if (!readonly_fd->is_valid()) {
         DPLOG(ERROR) << "open(\"" << path->value() << "\", O_RDONLY) failed";
         fp->reset();
         return false;
       }
     }
   }
   return true;
 }
-#endif  // !defined(OS_ANDROID)
 }
 
 SharedMemory::SharedMemory()
     : mapped_file_(-1),
       readonly_mapped_file_(-1),
       mapped_size_(0),
       memory_(NULL),
       read_only_(false),
-      requested_size_(0) {
-}
+      requested_size_(0) {}
 
-SharedMemory::SharedMemory(SharedMemoryHandle handle, bool read_only)
-    : mapped_file_(handle.fd),
+SharedMemory::SharedMemory(const SharedMemoryHandle& handle, bool read_only)
+    : mapped_file_(GetFdFromSharedMemoryHandle(handle)),
       readonly_mapped_file_(-1),
       mapped_size_(0),
       memory_(NULL),
       read_only_(read_only),
-      requested_size_(0) {
-}
+      requested_size_(0) {}
 
-SharedMemory::SharedMemory(SharedMemoryHandle handle, bool read_only,
+SharedMemory::SharedMemory(const SharedMemoryHandle& handle,
+                           bool read_only,
                            ProcessHandle process)
-    : mapped_file_(handle.fd),
+    : mapped_file_(GetFdFromSharedMemoryHandle(handle)),
       readonly_mapped_file_(-1),
       mapped_size_(0),
       memory_(NULL),
       read_only_(read_only),
       requested_size_(0) {
   // We don't handle this case yet (note the ignored parameter); let's die if
   // someone comes calling.
   NOTREACHED();
 }
 
 SharedMemory::~SharedMemory() {
   Unmap();
   Close();
 }
 
 // static
 bool SharedMemory::IsHandleValid(const SharedMemoryHandle& handle) {
-  return handle.fd >= 0;
+  return handle.IsValid();
 }
 
 // static
 SharedMemoryHandle SharedMemory::NULLHandle() {
   return SharedMemoryHandle();
 }
 
 // static
 void SharedMemory::CloseHandle(const SharedMemoryHandle& handle) {
-  DCHECK_GE(handle.fd, 0);
-  if (close(handle.fd) < 0)
+  DCHECK_GE(GetFdFromSharedMemoryHandle(handle), 0);
+  if (close(GetFdFromSharedMemoryHandle(handle)) < 0)
     DPLOG(ERROR) << "close";
 }
 
 // static
 size_t SharedMemory::GetHandleLimit() {
   return base::GetMaxFds();
 }
 
 // static
 SharedMemoryHandle SharedMemory::DuplicateHandle(
     const SharedMemoryHandle& handle) {
-  int duped_handle = HANDLE_EINTR(dup(handle.fd));
-  if (duped_handle < 0)
-    return base::SharedMemory::NULLHandle();
-  return base::FileDescriptor(duped_handle, true);
+  return handle.Duplicate();
 }
 
 // static
 int SharedMemory::GetFdFromSharedMemoryHandle(
     const SharedMemoryHandle& handle) {
-  return handle.fd;
+  return handle.GetFileDescriptor().fd;
 }
 
 bool SharedMemory::CreateAndMapAnonymous(size_t size) {
   return CreateAnonymous(size) && Map(size);
 }
 
-#if !defined(OS_ANDROID)
 // static
 int SharedMemory::GetSizeFromSharedMemoryHandle(
     const SharedMemoryHandle& handle) {
   struct stat st;
-  if (fstat(handle.fd, &st) != 0)
+  if (fstat(GetFdFromSharedMemoryHandle(handle), &st) != 0)
     return -1;
   return st.st_size;
 }
 
 // Chromium mostly only uses the unique/private shmem as specified by
 // "name == L"". The exception is in the StatsTable.
 // TODO(jrg): there is no way to "clean up" all unused named shmem if
 // we restart from a crash.  (That isn't a new problem, but it is a problem.)
 // In case we want to delete it later, it may be useful to save the value
 // of mem_filename after FilePathForMemoryName().
 bool SharedMemory::Create(const SharedMemoryCreateOptions& options) {
   // TODO(erikchen): Remove ScopedTracker below once http://crbug.com/466437
   // is fixed.
   tracked_objects::ScopedTracker tracking_profile1(
-      FROM_HERE_WITH_EXPLICIT_FUNCTION(
-          "466437 SharedMemory::Create::Start"));
+      FROM_HERE_WITH_EXPLICIT_FUNCTION("466437 SharedMemory::Create::Start"));
   DCHECK_EQ(-1, mapped_file_);
-  if (options.size == 0) return false;
+  if (options.size == 0)
+    return false;
 
   if (options.size > static_cast<size_t>(std::numeric_limits<int>::max()))
     return false;
 
   // This function theoretically can block on the disk, but realistically
   // the temporary files we create will just go into the buffer cache
   // and be deleted before they ever make it out to disk.
   base::ThreadRestrictions::ScopedAllowIO allow_io;
 
   ScopedFILE fp;
@@ skipping 27 matching lines @@
       //   is opened, so O_NOFOLLOW is passed to open().
       fd = HANDLE_EINTR(
           open(path.value().c_str(), O_RDWR | O_APPEND | O_NOFOLLOW));
 
       // Check that the current user owns the file.
       // If uid != euid, then a more complex permission model is used and this
       // API is not appropriate.
       const uid_t real_uid = getuid();
       const uid_t effective_uid = geteuid();
       struct stat sb;
-      if (fd >= 0 &&
-          (fstat(fd, &sb) != 0 || sb.st_uid != real_uid ||
-           sb.st_uid != effective_uid)) {
-        LOG(ERROR) <<
-            "Invalid owner when opening existing shared memory file.";
+      if (fd >= 0 && (fstat(fd, &sb) != 0 || sb.st_uid != real_uid ||
+                      sb.st_uid != effective_uid)) {
+        LOG(ERROR) << "Invalid owner when opening existing shared memory file.";
         close(fd);
         return false;
       }
 
       // An existing file was opened, so its size should not be fixed.
       fix_size = false;
     }
 
     if (options.share_read_only) {
       // Also open as readonly so that we can ShareReadOnlyToProcess.
@@ skipping 16 matching lines @@
     if (fstat(fileno(fp.get()), &stat) != 0)
       return false;
     const size_t current_size = stat.st_size;
     if (current_size != options.size) {
       if (HANDLE_EINTR(ftruncate(fileno(fp.get()), options.size)) != 0)
         return false;
     }
     requested_size_ = options.size;
   }
   if (fp == NULL) {
-#if !defined(OS_MACOSX)
     PLOG(ERROR) << "Creating shared memory in " << path.value() << " failed";
-    FilePath dir = path.DirName();
-    if (access(dir.value().c_str(), W_OK | X_OK) < 0) {
-      PLOG(ERROR) << "Unable to access(W_OK|X_OK) " << dir.value();
-      if (dir.value() == "/dev/shm") {
-        LOG(FATAL) << "This is frequently caused by incorrect permissions on "
-                   << "/dev/shm.  Try 'sudo chmod 1777 /dev/shm' to fix.";
-      }
-    }
-#else
-    PLOG(ERROR) << "Creating shared memory in " << path.value() << " failed";
-#endif
     return false;
   }
 
   return PrepareMapFile(fp.Pass(), readonly_fd.Pass());
 }
 
 // Our current implementation of shmem is with mmap()ing of files.
 // These files need to be deleted explicitly.
 // In practice this call is only needed for unit tests.
 bool SharedMemory::Delete(const std::string& name) {
   FilePath path;
   if (!FilePathForMemoryName(name, &path))
     return false;
 
   if (PathExists(path))
     return base::DeleteFile(path, false);
 
   // Doesn't exist, so success.
   return true;
 }
 
 bool SharedMemory::Open(const std::string& name, bool read_only) {
   FilePath path;
   if (!FilePathForMemoryName(name, &path))
     return false;
 
   read_only_ = read_only;
 
-  const char *mode = read_only ? "r" : "r+";
+  const char* mode = read_only ? "r" : "r+";
   ScopedFILE fp(base::OpenFile(path, mode));
   ScopedFD readonly_fd(HANDLE_EINTR(open(path.value().c_str(), O_RDONLY)));
   if (!readonly_fd.is_valid()) {
     DPLOG(ERROR) << "open(\"" << path.value() << "\", O_RDONLY) failed";
     return false;
   }
   return PrepareMapFile(fp.Pass(), readonly_fd.Pass());
 }
-#endif  // !defined(OS_ANDROID)
 
 bool SharedMemory::MapAt(off_t offset, size_t bytes) {
   if (mapped_file_ == -1)
     return false;
 
   if (bytes > static_cast<size_t>(std::numeric_limits<int>::max()))
     return false;
 
   if (memory_)
     return false;
 
-#if defined(OS_ANDROID)
-  // On Android, Map can be called with a size and offset of zero to use the
-  // ashmem-determined size.
-  if (bytes == 0) {
-    DCHECK_EQ(0, offset);
-    int ashmem_bytes = ashmem_get_size_region(mapped_file_);
-    if (ashmem_bytes < 0)
-      return false;
-    bytes = ashmem_bytes;
-  }
-#endif
-
   memory_ = mmap(NULL, bytes, PROT_READ | (read_only_ ? 0 : PROT_WRITE),
                  MAP_SHARED, mapped_file_, offset);
 
   bool mmap_succeeded = memory_ != (void*)-1 && memory_ != NULL;
   if (mmap_succeeded) {
     mapped_size_ = bytes;
     DCHECK_EQ(0U, reinterpret_cast<uintptr_t>(memory_) &
-        (SharedMemory::MAP_MINIMUM_ALIGNMENT - 1));
+                      (SharedMemory::MAP_MINIMUM_ALIGNMENT - 1));
   } else {
     memory_ = NULL;
   }
 
   return mmap_succeeded;
 }
 
 bool SharedMemory::Unmap() {
   if (memory_ == NULL)
     return false;
 
   munmap(memory_, mapped_size_);
   memory_ = NULL;
   mapped_size_ = 0;
   return true;
 }
 
 SharedMemoryHandle SharedMemory::handle() const {
-  return FileDescriptor(mapped_file_, false);
+  return SharedMemoryHandle(mapped_file_, false);
 }
 
 void SharedMemory::Close() {
   if (mapped_file_ > 0) {
     if (close(mapped_file_) < 0)
       PLOG(ERROR) << "close";
     mapped_file_ = -1;
   }
   if (readonly_mapped_file_ > 0) {
     if (close(readonly_mapped_file_) < 0)
       PLOG(ERROR) << "close";
     readonly_mapped_file_ = -1;
   }
 }
 
-void SharedMemory::LockDeprecated() {
-  g_thread_lock_.Get().Acquire();
-  LockOrUnlockCommon(F_LOCK);
-}
-
-void SharedMemory::UnlockDeprecated() {
-  LockOrUnlockCommon(F_ULOCK);
-  g_thread_lock_.Get().Release();
-}
-
-#if !defined(OS_ANDROID)
 bool SharedMemory::PrepareMapFile(ScopedFILE fp, ScopedFD readonly_fd) {
   DCHECK_EQ(-1, mapped_file_);
   DCHECK_EQ(-1, readonly_mapped_file_);
   if (fp == NULL)
     return false;
 
   // This function theoretically can block on the disk, but realistically
   // the temporary files we create will just go into the buffer cache
   // and be deleted before they ever make it out to disk.
   base::ThreadRestrictions::ScopedAllowIO allow_io;
@@ skipping 32 matching lines @@
                                          FilePath* path) {
   // mem_name will be used for a filename; make sure it doesn't
   // contain anything which will confuse us.
   DCHECK_EQ(std::string::npos, mem_name.find('/'));
   DCHECK_EQ(std::string::npos, mem_name.find('\0'));
 
   FilePath temp_dir;
   if (!GetShmemTempDir(false, &temp_dir))
     return false;
 
-#if !defined(OS_MACOSX)
-#if defined(GOOGLE_CHROME_BUILD)
-  std::string name_base = std::string("com.google.Chrome");
-#else
-  std::string name_base = std::string("org.chromium.Chromium");
-#endif
-#else  // OS_MACOSX
   std::string name_base = std::string(base::mac::BaseBundleID());
-#endif  // OS_MACOSX
   *path = temp_dir.AppendASCII(name_base + ".shmem." + mem_name);
   return true;
 }
-#endif  // !defined(OS_ANDROID)
-
-void SharedMemory::LockOrUnlockCommon(int function) {
-  DCHECK_GE(mapped_file_, 0);
-  while (lockf(mapped_file_, function, 0) < 0) {
-    if (errno == EINTR) {
-      continue;
-    } else if (errno == ENOLCK) {
-      // temporary kernel resource exaustion
-      base::PlatformThread::Sleep(base::TimeDelta::FromMilliseconds(500));
-      continue;
-    } else {
-      NOTREACHED() << "lockf() failed."
-                   << " function:" << function
-                   << " fd:" << mapped_file_
-                   << " errno:" << errno
-                   << " msg:" << base::safe_strerror(errno);
-    }
-  }
-}
 
 bool SharedMemory::ShareToProcessCommon(ProcessHandle process,
                                         SharedMemoryHandle* new_handle,
                                         bool close_self,
                                         ShareMode share_mode) {
   int handle_to_dup = -1;
-  switch(share_mode) {
+  switch (share_mode) {
     case SHARE_CURRENT_MODE:
       handle_to_dup = mapped_file_;
       break;
     case SHARE_READONLY:
       // We could imagine re-opening the file from /dev/fd, but that can't make
       // it readonly on Mac: https://codereview.chromium.org/27265002/#msg10
       CHECK_GE(readonly_mapped_file_, 0);
       handle_to_dup = readonly_mapped_file_;
       break;
   }
 
   const int new_fd = HANDLE_EINTR(dup(handle_to_dup));
   if (new_fd < 0) {
     DPLOG(ERROR) << "dup() failed.";
     return false;
   }
 
-  new_handle->fd = new_fd;
-  new_handle->auto_close = true;
+  new_handle->SetFileHandle(new_fd, true);
 
   if (close_self) {
     Unmap();
     Close();
   }
 
   return true;
 }
 
 }  // namespace base