content/public/browser/file_descriptor_info.h

   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 #ifndef CONTENT_PUBLIC_BROWSER_FILE_DESCRIPTOR_INFO_H_
   6 #define CONTENT_PUBLIC_BROWSER_FILE_DESCRIPTOR_INFO_H_
   7
   8 #include "base/files/file.h"
   9 #include "base/process/launch.h"
  10
  11 namespace content {
  12
  13 // FileDescriptorInfo is a collection of file descriptors which is
  14 // needed to launch a process. You should tell FileDescriptorInfo
  15 // which FD should be closed and which shouldn't so that it can take care
  16 // of the lifetime of FDs.
  17 //
  18 // See base/process/launcher.h for more details about launching a
  19 // process.
  20 class FileDescriptorInfo {
  21  public:
  22   virtual ~FileDescriptorInfo() {}
  23
  24   // Add an FD associated with an ID, without delegating the ownerhip
  25   // of ID.
  26   virtual void Share(int id, base::PlatformFile fd) = 0;
  27
  28   // Add an FD associated with an ID, passing the FD ownership to
  29   // FileDescriptorInfo.
  30   virtual void Transfer(int id, base::ScopedFD fd) = 0;
  31
  32   // A vecotr backed map of registered ID-FD pairs.
  33   virtual const base::FileHandleMappingVector& GetMapping() const = 0;
  34
  35   // A GetMapping() variant what adjusts the ID value by |delta|.
  36   // Some environments need this trick.
  37   virtual base::FileHandleMappingVector GetMappingWithIDAdjustment(
  38       int delta) const = 0;
  39
  40   // API for iterating registered ID-FD pairs.
  41   virtual base::PlatformFile GetFDAt(size_t i) const = 0;
  42   virtual int GetIDAt(size_t i) const = 0;
  43   virtual size_t GetMappingSize() const = 0;
  44
  45   // True if |this| has an ownership of |file|.
  46   virtual bool OwnsFD(base::PlatformFile file) const = 0;
  47   // Assuming |OwnsFD(file)|, release the ownership.
  48   virtual base::ScopedFD ReleaseFD(base::PlatformFile file) = 0;
  49 };
  50
  51 }
  52
  53 #endif  // CONTENT_PUBLIC_BROWSER_FILE_DESCRIPTOR_INFO_H_