1.1 --- /dev/null	Thu Jan 01 00:00:00 1970 +0000
     1.2 +++ b/os/persistentdata/persistentstorage/sql/SQLite364/hash.h	Fri Jun 15 03:10:57 2012 +0200
     1.3 @@ -0,0 +1,87 @@
     1.4 +/*
     1.5 +** 2001 September 22
     1.6 +**
     1.7 +** The author disclaims copyright to this source code.  In place of
     1.8 +** a legal notice, here is a blessing:
     1.9 +**
    1.10 +**    May you do good and not evil.
    1.11 +**    May you find forgiveness for yourself and forgive others.
    1.12 +**    May you share freely, never taking more than you give.
    1.13 +**
    1.14 +*************************************************************************
    1.15 +** This is the header file for the generic hash-table implemenation
    1.16 +** used in SQLite.
    1.17 +**
    1.18 +** $Id: hash.h,v 1.12 2008/10/10 17:41:29 drh Exp $
    1.19 +*/
    1.20 +#ifndef _SQLITE_HASH_H_
    1.21 +#define _SQLITE_HASH_H_
    1.22 +
    1.23 +/* Forward declarations of structures. */
    1.24 +typedef struct Hash Hash;
    1.25 +typedef struct HashElem HashElem;
    1.26 +
    1.27 +/* A complete hash table is an instance of the following structure.
    1.28 +** The internals of this structure are intended to be opaque -- client
    1.29 +** code should not attempt to access or modify the fields of this structure
    1.30 +** directly.  Change this structure only by using the routines below.
    1.31 +** However, many of the "procedures" and "functions" for modifying and
    1.32 +** accessing this structure are really macros, so we can't really make
    1.33 +** this structure opaque.
    1.34 +*/
    1.35 +struct Hash {
    1.36 +  unsigned int copyKey: 1;  /* True if copy of key made on insert */
    1.37 +  unsigned int htsize : 31; /* Number of buckets in the hash table */
    1.38 +  unsigned int count;       /* Number of entries in this table */
    1.39 +  HashElem *first;          /* The first element of the array */
    1.40 +  struct _ht {              /* the hash table */
    1.41 +    int count;                 /* Number of entries with this hash */
    1.42 +    HashElem *chain;           /* Pointer to first entry with this hash */
    1.43 +  } *ht;
    1.44 +};
    1.45 +
    1.46 +/* Each element in the hash table is an instance of the following 
    1.47 +** structure.  All elements are stored on a single doubly-linked list.
    1.48 +**
    1.49 +** Again, this structure is intended to be opaque, but it can't really
    1.50 +** be opaque because it is used by macros.
    1.51 +*/
    1.52 +struct HashElem {
    1.53 +  HashElem *next, *prev;   /* Next and previous elements in the table */
    1.54 +  void *data;              /* Data associated with this element */
    1.55 +  void *pKey; int nKey;    /* Key associated with this element */
    1.56 +};
    1.57 +
    1.58 +/*
    1.59 +** Access routines.  To delete, insert a NULL pointer.
    1.60 +*/
    1.61 +void sqlite3HashInit(Hash*, int copyKey);
    1.62 +void *sqlite3HashInsert(Hash*, const void *pKey, int nKey, void *pData);
    1.63 +void *sqlite3HashFind(const Hash*, const void *pKey, int nKey);
    1.64 +HashElem *sqlite3HashFindElem(const Hash*, const void *pKey, int nKey);
    1.65 +void sqlite3HashClear(Hash*);
    1.66 +
    1.67 +/*
    1.68 +** Macros for looping over all elements of a hash table.  The idiom is
    1.69 +** like this:
    1.70 +**
    1.71 +**   Hash h;
    1.72 +**   HashElem *p;
    1.73 +**   ...
    1.74 +**   for(p=sqliteHashFirst(&h); p; p=sqliteHashNext(p)){
    1.75 +**     SomeStructure *pData = sqliteHashData(p);
    1.76 +**     // do something with pData
    1.77 +**   }
    1.78 +*/
    1.79 +#define sqliteHashFirst(H)  ((H)->first)
    1.80 +#define sqliteHashNext(E)   ((E)->next)
    1.81 +#define sqliteHashData(E)   ((E)->data)
    1.82 +#define sqliteHashKey(E)    ((E)->pKey)
    1.83 +#define sqliteHashKeysize(E) ((E)->nKey)
    1.84 +
    1.85 +/*
    1.86 +** Number of entries in a hash table
    1.87 +*/
    1.88 +#define sqliteHashCount(H)  ((H)->count)
    1.89 +
    1.90 +#endif /* _SQLITE_HASH_H_ */