src/add-ons/kernel/file_systems/btrfs/AttributeIterator.cpp

   1 /*
   2  * Copyright 2011, Jérôme Duval, korli@users.berlios.de.
   3  * This file may be used under the terms of the MIT License.
   4  */
   5
   6
   7 #include "AttributeIterator.h"
   8
   9
  10 //#define TRACE_BTRFS
  11 #ifdef TRACE_BTRFS
  12 #       define TRACE(x...) dprintf("\33[34mbtrfs:\33[0m " x)
  13 #else
  14 #       define TRACE(x...) ;
  15 #endif
  16 #       define ERROR(x...) dprintf("\33[34mbtrfs:\33[0m " x)
  17
  18
  19 AttributeIterator::AttributeIterator(Inode* inode)
  20         :
  21         fOffset(-1ULL),
  22         fInode(inode),
  23         fIterator(NULL)
  24 {
  25         struct btrfs_key key;
  26         key.SetType(BTRFS_KEY_TYPE_XATTR_ITEM);
  27         key.SetObjectID(inode->ID());
  28         fIterator = new(std::nothrow) TreeIterator(inode->GetVolume()->FSTree(),
  29                 key);
  30 }
  31
  32
  33 AttributeIterator::~AttributeIterator()
  34 {
  35         delete fIterator;
  36 }
  37
  38
  39 status_t
  40 AttributeIterator::InitCheck()
  41 {
  42         return fIterator != NULL ? B_OK : B_NO_MEMORY;
  43 }
  44
  45
  46 status_t
  47 AttributeIterator::GetNext(char* name, size_t* _nameLength)
  48 {
  49         btrfs_key key;
  50         btrfs_dir_entry* entries;
  51         uint32 entries_length;
  52         status_t status = fIterator->GetPreviousEntry(key, (void**)&entries,
  53                 &entries_length);
  54         if (status != B_OK)
  55                 return status;
  56
  57         btrfs_dir_entry* entry = entries;
  58         uint16 current = 0;
  59         while (current < entries_length) {
  60                 current += entry->Length();
  61                 break;
  62                 // TODO there could be several entries with the same name hash
  63                 entry = (btrfs_dir_entry*)((uint8*)entry + entry->Length());
  64         }
  65
  66         TRACE("DirectoryIterator::GetNext() entries_length %ld name_length %d\n",
  67                 entries_length, entry->NameLength());
  68
  69         memcpy(name, entry + 1, entry->NameLength());
  70         name[entry->NameLength()] = '\0';
  71         *_nameLength = entry->NameLength();
  72         free(entries);
  73
  74         return B_OK;
  75 }
  76
  77
  78 status_t
  79 AttributeIterator::Rewind()
  80 {
  81         fIterator->Rewind();
  82         fOffset = -1ULL;
  83         return B_OK;
  84 }