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