headers/private/storage/MergedDirectory.h

   1 /*
   2  * Copyright 2013, Haiku, Inc. All Rights Reserved.
   3  * Distributed under the terms of the MIT License.
   4  *
   5  * Authors:
   6  *              Ingo Weinhold <ingo_weinhold@gmx.de>
   7  */
   8 #ifndef _MERGED_DIRECTORY_H
   9 #define _MERGED_DIRECTORY_H
  10
  11
  12 #include <EntryList.h>
  13 #include <ObjectList.h>
  14
  15
  16 class BDirectory;
  17
  18
  19 class BMergedDirectory : public BEntryList {
  20 public:
  21                         // policy how to handle equally named entries in different
  22                         // directories
  23                         enum BPolicy {
  24                                 B_ALLOW_DUPLICATES,
  25                                 B_ALWAYS_FIRST,
  26                                 B_COMPARE
  27                         };
  28
  29 public:
  30                                                                 BMergedDirectory(
  31                                                                         BPolicy policy = B_ALWAYS_FIRST);
  32         virtual                                         ~BMergedDirectory();
  33
  34                         status_t                        Init();
  35
  36                         BPolicy                         Policy() const;
  37                         void                            SetPolicy(BPolicy policy);
  38
  39                         status_t                        AddDirectory(BDirectory* directory);
  40                         status_t                        AddDirectory(const char* path);
  41
  42         virtual status_t                        GetNextEntry(BEntry* entry,
  43                                                                         bool traverse = false);
  44         virtual status_t                        GetNextRef(entry_ref* ref);
  45         virtual int32                           GetNextDirents(struct dirent* direntBuffer,
  46                                                                         size_t bufferSize,
  47                                                                         int32 maxEntries = INT_MAX);
  48         virtual status_t                        Rewind();
  49         virtual int32                           CountEntries();
  50
  51 protected:
  52         virtual bool                            ShallPreferFirstEntry(const entry_ref& entry1,
  53                                                                         int32 index1, const entry_ref& entry2,
  54                                                                         int32 index2);
  55                                                                         // always invoked with index1 < index2
  56
  57 private:
  58                         typedef BObjectList<BDirectory> DirectoryList;
  59                         struct EntryNameSet;
  60
  61 private:
  62                         void                            _FindBestEntry(dirent* direntBuffer);
  63
  64 private:
  65                         DirectoryList           fDirectories;
  66                         BPolicy                         fPolicy;
  67                         int32                           fDirectoryIndex;
  68                         EntryNameSet*           fVisitedEntries;
  69 };
  70
  71
  72 #endif  // _MERGED_DIRECTORY_H