base/memory/shared_memory_handle_mac.cc

   1 // Copyright 2015 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/memory/shared_memory_handle.h"
   6
   7 #include <unistd.h>
   8
   9 #include "base/posix/eintr_wrapper.h"
  10
  11 #if defined(OS_MACOSX) && !defined(OS_IOS)
  12 namespace base {
  13
  14 static_assert(sizeof(SharedMemoryHandle::Type) <=
  15                   sizeof(SharedMemoryHandle::TypeWireFormat),
  16               "Size of enum SharedMemoryHandle::Type exceeds size of type "
  17               "transmitted over wire.");
  18
  19 SharedMemoryHandle::SharedMemoryHandle() : type_(POSIX), file_descriptor_() {
  20 }
  21
  22 SharedMemoryHandle::SharedMemoryHandle(
  23     const base::FileDescriptor& file_descriptor)
  24     : type_(POSIX), file_descriptor_(file_descriptor) {
  25 }
  26
  27 SharedMemoryHandle::SharedMemoryHandle(int fd, bool auto_close)
  28     : type_(POSIX), file_descriptor_(fd, auto_close) {
  29 }
  30
  31 SharedMemoryHandle::SharedMemoryHandle(const SharedMemoryHandle& handle)
  32     : type_(handle.type_), file_descriptor_(handle.file_descriptor_) {
  33 }
  34
  35 SharedMemoryHandle& SharedMemoryHandle::operator=(
  36     const SharedMemoryHandle& handle) {
  37   if (this == &handle)
  38     return *this;
  39
  40   type_ = handle.type_;
  41   file_descriptor_ = handle.file_descriptor_;
  42   return *this;
  43 }
  44
  45 bool SharedMemoryHandle::operator==(const SharedMemoryHandle& handle) const {
  46   // Invalid handles are always equal, even if they have different types.
  47   if (!IsValid() && !handle.IsValid())
  48     return true;
  49
  50   return type_ == handle.type_ && file_descriptor_ == handle.file_descriptor_;
  51 }
  52
  53 bool SharedMemoryHandle::operator!=(const SharedMemoryHandle& handle) const {
  54   return !(*this == handle);
  55 }
  56
  57 SharedMemoryHandle::Type SharedMemoryHandle::GetType() const {
  58   return type_;
  59 }
  60
  61 bool SharedMemoryHandle::IsValid() const {
  62   switch (type_) {
  63     case POSIX:
  64       return file_descriptor_.fd >= 0;
  65     case MACH:
  66       return false;
  67   }
  68 }
  69
  70 void SharedMemoryHandle::SetFileHandle(int fd, bool auto_close) {
  71   DCHECK_EQ(type_, POSIX);
  72   file_descriptor_.fd = fd;
  73   file_descriptor_.auto_close = auto_close;
  74 }
  75
  76 const FileDescriptor SharedMemoryHandle::GetFileDescriptor() const {
  77   DCHECK_EQ(type_, POSIX);
  78   return file_descriptor_;
  79 }
  80
  81 SharedMemoryHandle SharedMemoryHandle::Duplicate() const {
  82   DCHECK_EQ(type_, POSIX);
  83   int duped_handle = HANDLE_EINTR(dup(file_descriptor_.fd));
  84   if (duped_handle < 0)
  85     return SharedMemoryHandle();
  86   return SharedMemoryHandle(duped_handle, true);
  87 }
  88
  89 }  // namespace base
  90 #endif  // defined(OS_MACOSX) && !defined(OS_IOS)