Turn FileDescriptorInfo a collection class

content/public/browser/file_descriptor_info.h

 // 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.
 
 #ifndef CONTENT_PUBLIC_BROWSER_FILE_DESCRIPTOR_INFO_H_
 #define CONTENT_PUBLIC_BROWSER_FILE_DESCRIPTOR_INFO_H_
 
-#include "base/file_descriptor_posix.h"
+#include "base/files/file.h"
+#include "base/process/launch.h"
 
 namespace content {
 
-// This struct is used when passing files that should be mapped in a process
-// that is been created and allows to associate that file with a specific ID.
-// It also provides a way to know if the actual file descriptor should be
-// closed with the FileDescriptor.auto_close field.
+// FileDescriptorInfo is a collection of file descriptors which is
+// needed to launch a process. You should tell FileDescriptorInfo
+// which FD should be closed and which shouldn't so that it can take care
+// of the lifetime of FDs.
+//
+// See base/process/launcher.h for more details about launching a
+// process.
+class FileDescriptorInfo {
+ public:
+  virtual ~FileDescriptorInfo() {}
 
-struct FileDescriptorInfo {
-  FileDescriptorInfo(int id, const base::FileDescriptor& file_descriptor)
-      : id(id),
-        fd(file_descriptor) {
-  }
+  // Add an FD associated with an ID, without delegating the ownerhip
+  // of ID.
+  virtual void Share(int id, base::PlatformFile fd) = 0;
 
-  int id;
-  base::FileDescriptor fd;
+  // Add an FD associated with an ID, passing the FD ownership to
+  // FileDescriptorInfo.
+  virtual void Transfer(int id, base::ScopedFD fd) = 0;
+
+  // A vecotr backed map of registered ID-FD pairs.
+  virtual const base::FileHandleMappingVector& GetMapping() const = 0;
+
+  // A GetMapping() variant what adjusts the ID value by |delta|.
+  // Some environments need this trick.
+  virtual base::FileHandleMappingVector GetMappingWithIDAdjustment(
+      int delta) const = 0;
+
+  // API for iterating registered ID-FD pairs.
+  virtual base::PlatformFile GetFDAt(size_t i) const = 0;
+  virtual int GetIDAt(size_t i) const = 0;
+  virtual size_t GetMappingSize() const = 0;
 };
 
 }
 
 #endif  // CONTENT_PUBLIC_BROWSER_FILE_DESCRIPTOR_INFO_H_