linux: components support for base/

base/file_descriptor_shuffle.h

-// Copyright (c) 2009 The Chromium Authors. All rights reserved.
+// Copyright (c) 2011 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 BASE_FILE_DESCRIPTOR_SHUFFLE_H_
 #define BASE_FILE_DESCRIPTOR_SHUFFLE_H_
 #pragma once
 
 // This code exists to perform the shuffling of file descriptors which is
 // commonly needed when forking subprocesses. The naive approve is very simple,
 // just call dup2 to setup the desired descriptors, but wrong. It's tough to
 // handle the edge cases (like mapping 0 -> 1, 1 -> 0) correctly.
 //
 // In order to unittest this code, it's broken into the abstract action (an
 // injective multimap) and the concrete code for dealing with file descriptors.
 // Users should use the code like this:
 //   base::InjectiveMultimap file_descriptor_map;
 //   file_descriptor_map.push_back(base::InjectionArc(devnull, 0, true));
 //   file_descriptor_map.push_back(base::InjectionArc(devnull, 2, true));
 //   file_descriptor_map.push_back(base::InjectionArc(pipe[1], 1, true));
 //   base::ShuffleFileDescriptors(file_descriptor_map);
 //
 // and trust the the Right Thing will get done.
 
 #include <vector>
 
+#include "base/base_api.h"
+
 namespace base {
 
 // A Delegate which performs the actions required to perform an injective
 // multimapping in place.
 class InjectionDelegate {
  public:
   // Duplicate |fd|, an element of the domain, and write a fresh element of the
   // domain into |result|. Returns true iff successful.
   virtual bool Duplicate(int* result, int fd) = 0;
   // Destructively move |src| to |dest|, overwriting |dest|. Returns true iff
@@ skipping 23 matching lines @@
   }
 
   int source;
   int dest;
   bool close;  // if true, delete the source element after performing the
                // mapping.
 };
 
 typedef std::vector<InjectionArc> InjectiveMultimap;
 
-bool PerformInjectiveMultimap(const InjectiveMultimap& map,
-                              InjectionDelegate* delegate);
+BASE_API bool PerformInjectiveMultimap(const InjectiveMultimap& map,
+                                       InjectionDelegate* delegate);
 
-bool PerformInjectiveMultimapDestructive(InjectiveMultimap* map,
-                                         InjectionDelegate* delegate);
+BASE_API bool PerformInjectiveMultimapDestructive(InjectiveMultimap* map,
+                                                  InjectionDelegate* delegate);
 
 // This function will not call malloc but will mutate |map|
 static inline bool ShuffleFileDescriptors(InjectiveMultimap* map) {
   FileDescriptorTableInjection delegate;
   return PerformInjectiveMultimapDestructive(map, &delegate);
 }
 
 }  // namespace base
 
 #endif  // BASE_FILE_DESCRIPTOR_SHUFFLE_H_