src/bin/bfs_tools/lib/BPlusTree.h

   1 #ifndef B_PLUS_TREE_H
   2 #define B_PLUS_TREE_H
   3 /* BPlusTree - BFS B+Tree implementation
   4 **
   5 ** Copyright 2001 pinc Software. All Rights Reserved.
   6 */
   7
   8 #include <List.h>
   9
  10 #include <string.h>
  11
  12 #include "Cache.h"
  13 #include "bfs.h"
  14
  15
  16 class BPositionIO;
  17
  18
  19 // ****************** on-disk structures ********************
  20
  21 #define BPLUSTREE_NULL                  -1LL
  22 #define BPLUSTREE_FREE                  -2LL
  23
  24 struct __attribute__((packed)) bplustree_header
  25 {
  26         uint32          magic;
  27         uint32          node_size;
  28         uint32          max_number_of_levels;
  29         uint32          data_type;
  30         off_t           root_node_pointer;
  31         off_t           free_node_pointer;
  32         off_t           maximum_size;
  33
  34         inline bool IsValidLink(off_t link);
  35 };
  36
  37 #define BPLUSTREE_MAGIC                         0x69f6c2e8
  38 #define BPLUSTREE_NODE_SIZE             1024
  39 #define BPLUSTREE_MAX_KEY_LENGTH        256
  40 #define BPLUSTREE_MIN_KEY_LENGTH        1
  41
  42 enum bplustree_types {
  43         BPLUSTREE_STRING_TYPE   = 0,
  44         BPLUSTREE_INT32_TYPE    = 1,
  45         BPLUSTREE_UINT32_TYPE   = 2,
  46         BPLUSTREE_INT64_TYPE    = 3,
  47         BPLUSTREE_UINT64_TYPE   = 4,
  48         BPLUSTREE_FLOAT_TYPE    = 5,
  49         BPLUSTREE_DOUBLE_TYPE   = 6
  50 };
  51
  52 struct __attribute((packed)) bplustree_node {
  53         off_t   left_link;
  54         off_t   right_link;
  55         off_t   overflow_link;
  56         uint16  all_key_count;
  57         uint16  all_key_length;
  58
  59         inline uint16 *KeyLengths() const;
  60         inline off_t *Values() const;
  61         inline uint8 *Keys() const;
  62         inline int32 Used() const;
  63         uint8 *KeyAt(int32 index, uint16 *keyLength) const;
  64
  65         uint8 CountDuplicates(off_t offset, bool isFragment) const;
  66         off_t DuplicateAt(off_t offset, bool isFragment, int8 index) const;
  67
  68         static inline uint8 LinkType(off_t link);
  69         static inline off_t FragmentOffset(off_t link);
  70 };
  71
  72 #define BPLUSTREE_NODE 0
  73 #define BPLUSTREE_DUPLICATE_NODE 2
  74 #define BPLUSTREE_DUPLICATE_FRAGMENT 3
  75
  76 // **************************************
  77
  78 enum bplustree_traversing {
  79         BPLUSTREE_FORWARD = 1,
  80         BPLUSTREE_BACKWARD = -1,
  81
  82         BPLUSTREE_BEGIN = 0,
  83         BPLUSTREE_END = 1
  84 };
  85
  86 template<class T> class Stack;
  87 class BPlusTree;
  88
  89 class NodeCache : public Cache<off_t> {
  90         public:
  91                 NodeCache(BPlusTree *);
  92
  93                 virtual Cacheable *NewCacheable(off_t offset);
  94                 bplustree_node *Get(off_t offset);
  95 //              void SetOffset(bplustree_node *, off_t offset);
  96
  97         protected:
  98                 BPlusTree       *fTree;
  99 };
 100
 101
 102 class BPlusTree {
 103         public:
 104                 BPlusTree(int32 keyType, int32 nodeSize = BPLUSTREE_NODE_SIZE,
 105                         bool allowDuplicates = true);
 106                 BPlusTree(BPositionIO *stream, bool allowDuplicates = true);
 107                 BPlusTree();
 108                 ~BPlusTree();
 109
 110                 status_t        SetTo(int32 keyType,int32 nodeSize = BPLUSTREE_NODE_SIZE,bool allowDuplicates = true);
 111                 status_t        SetTo(BPositionIO *stream,bool allowDuplicates = true);
 112
 113                 status_t        InitCheck();
 114                 status_t        Validate(bool verbose = false);
 115
 116                 int32           Type() const { return fHeader->data_type; }
 117
 118                 status_t        Rewind();
 119                 status_t        Goto(int8 to);
 120                 status_t        GetNextEntry(void *key,uint16 *keyLength,uint16 maxLength,off_t *value);
 121                 status_t        GetPreviousEntry(void *key,uint16 *keyLength,uint16 maxLength,off_t *value);
 122
 123                 status_t        Insert(uint8 *key, uint16 keyLength, off_t value);
 124
 125                 status_t        Insert(const char *key, off_t value);
 126                 status_t        Insert(int32 key, off_t value);
 127                 status_t        Insert(uint32 key, off_t value);
 128                 status_t        Insert(int64 key, off_t value);
 129                 status_t        Insert(uint64 key, off_t value);
 130                 status_t        Insert(float key, off_t value);
 131                 status_t        Insert(double key, off_t value);
 132
 133                 status_t        Find(uint8 *key, uint16 keyLength, off_t *value);
 134
 135                 status_t        WriteTo(BPositionIO *stream);
 136
 137                 void            SetHoldChanges(bool hold);
 138
 139         private:
 140                 // needed for searching
 141                 struct node_and_key {
 142                         off_t   nodeOffset;
 143                         uint16  keyIndex;
 144                 };
 145
 146                 void            Initialize(int32 nodeSize);
 147
 148                 void            SetCurrentNode(bplustree_node *node,off_t offset,int8 to = BPLUSTREE_BEGIN);
 149                 status_t        Traverse(int8 direction,void *key,uint16 *keyLength,uint16 maxLength,off_t *value);
 150
 151                 int32           CompareKeys(const void *key1, int keylength1, const void *key2, int keylength2);
 152                 status_t        FindKey(bplustree_node *node, uint8 *key, uint16 keyLength, uint16 *index = NULL, off_t *next = NULL);
 153                 status_t        SeekDown(Stack<node_and_key> &stack, uint8 *key, uint16 keyLength);
 154
 155                 status_t        SplitNode(bplustree_node *node, off_t nodeOffset, uint16 *_keyIndex, uint8 *key, uint16 *_keyLength, off_t *_value);
 156
 157                 void            InsertKey(bplustree_node *node, uint8 *key, uint16 keyLength, off_t value, uint16 index);
 158                 status_t        InsertDuplicate(bplustree_node *node,uint16 index);
 159
 160                 bool            CheckNode(bplustree_node *node);
 161
 162         private:
 163                 friend class NodeCache;
 164                 bplustree_node *Node(off_t nodeoffset,bool check = true);
 165
 166         private:
 167                 BPositionIO     *fStream;
 168                 bplustree_header *fHeader;
 169                 int32           fNodeSize;
 170                 bool            fAllowDuplicates;
 171                 status_t        fStatus;
 172
 173                 NodeCache       fCache;
 174
 175                 off_t           fCurrentNodeOffset;     // traverse position
 176                 int32           fCurrentKey;
 177                 off_t           fDuplicateNode;
 178                 uint16          fDuplicate, fNumDuplicates;
 179                 bool            fIsFragment;
 180 };
 181
 182 // inline functions
 183
 184 inline status_t BPlusTree::Rewind()
 185 {
 186         return Goto(BPLUSTREE_BEGIN);
 187 }
 188
 189 inline status_t BPlusTree::GetNextEntry(void *key,uint16 *keyLength,uint16 maxLength,off_t *value)
 190 {
 191         return Traverse(BPLUSTREE_FORWARD,key,keyLength,maxLength,value);
 192 }
 193
 194 inline status_t BPlusTree::GetPreviousEntry(void *key,uint16 *keyLength,uint16 maxLength,off_t *value)
 195 {
 196         return Traverse(BPLUSTREE_BACKWARD,key,keyLength,maxLength,value);
 197 }
 198
 199 inline status_t BPlusTree::Insert(const char *key,off_t value)
 200 {
 201         if (fHeader->data_type != BPLUSTREE_STRING_TYPE)
 202                 return B_BAD_TYPE;
 203         return Insert((uint8 *)key, strlen(key), value);
 204 }
 205
 206 inline status_t BPlusTree::Insert(int32 key, off_t value)
 207 {
 208         if (fHeader->data_type != BPLUSTREE_INT32_TYPE)
 209                 return B_BAD_TYPE;
 210         return Insert((uint8 *)&key, sizeof(key), value);
 211 }
 212
 213 inline status_t BPlusTree::Insert(uint32 key, off_t value)
 214 {
 215         if (fHeader->data_type != BPLUSTREE_UINT32_TYPE)
 216                 return B_BAD_TYPE;
 217         return Insert((uint8 *)&key, sizeof(key), value);
 218 }
 219
 220 inline status_t BPlusTree::Insert(int64 key, off_t value)
 221 {
 222         if (fHeader->data_type != BPLUSTREE_INT64_TYPE)
 223                 return B_BAD_TYPE;
 224         return Insert((uint8 *)&key, sizeof(key), value);
 225 }
 226
 227 inline status_t BPlusTree::Insert(uint64 key, off_t value)
 228 {
 229         if (fHeader->data_type != BPLUSTREE_UINT64_TYPE)
 230                 return B_BAD_TYPE;
 231         return Insert((uint8 *)&key, sizeof(key), value);
 232 }
 233
 234 inline status_t BPlusTree::Insert(float key, off_t value)
 235 {
 236         if (fHeader->data_type != BPLUSTREE_FLOAT_TYPE)
 237                 return B_BAD_TYPE;
 238         return Insert((uint8 *)&key, sizeof(key), value);
 239 }
 240
 241 inline status_t BPlusTree::Insert(double key, off_t value)
 242 {
 243         if (fHeader->data_type != BPLUSTREE_DOUBLE_TYPE)
 244                 return B_BAD_TYPE;
 245         return Insert((uint8 *)&key, sizeof(key), value);
 246 }
 247
 248
 249 /************************ bplustree_header inline functions ************************/
 250 //      #pragma mark -
 251
 252
 253 inline bool bplustree_header::IsValidLink(off_t link)
 254 {
 255         return link == BPLUSTREE_NULL || (link > 0 && link <= maximum_size - node_size);
 256 }
 257
 258
 259 /************************ bplustree_node inline functions ************************/
 260 //      #pragma mark -
 261
 262
 263 inline uint16 *bplustree_node::KeyLengths() const
 264 {
 265         return (uint16 *)(((char *)this) + round_up(sizeof(bplustree_node) + all_key_length));
 266 }
 267
 268 inline off_t *bplustree_node::Values() const
 269 {
 270         return (off_t *)((char *)KeyLengths() + all_key_count * sizeof(uint16));
 271 }
 272
 273 inline uint8 *bplustree_node::Keys() const
 274 {
 275         return (uint8 *)this + sizeof(bplustree_node);
 276 }
 277
 278 inline int32 bplustree_node::Used() const
 279 {
 280         return round_up(sizeof(bplustree_node) + all_key_length) + all_key_count * (sizeof(uint16) + sizeof(off_t));
 281 }
 282
 283 inline uint8 bplustree_node::LinkType(off_t link)
 284 {
 285         return *(uint64 *)&link >> 62;
 286 }
 287
 288 inline off_t bplustree_node::FragmentOffset(off_t link)
 289 {
 290         return link & 0x3ffffffffffffc00LL;
 291 }
 292
 293 #endif  /* B_PLUS_TREE_H */