NextGraph
/
lmdb
mirror of https://github.com/nextgraph-org/lmdb.git
1
0
Fork 0
Code Issues Packages Projects Releases Wiki Activity

Minor tweaks, update relfunc behavior

Browse Source
vmware
Howard Chu 13 years ago
parent 25529a4c36
commit dc83777ab9
2 changed files with 52 additions and 18 deletions
Show all changes Ignore whitespace when comparing lines Ignore changes in amount of whitespace Ignore changes in whitespace at EOL
Show Stats Download Patch File Download Diff File
  1. 19
      libraries/libmdb/mdb.c
  2. 51
      libraries/libmdb/mdb.h

19
libraries/libmdb/mdb.c
Unescape View File

@ -662,6 +662,7 @@ typedef struct MDB_dbx {
MDB_cmp_func *md_cmp; /**< function for comparing keys */
MDB_cmp_func *md_dcmp; /**< function for comparing data items */
MDB_rel_func *md_rel; /**< user relocate function */
void *md_relctx; /**< user-provided context for md_rel */
MDB_dbi md_parent; /**< parent DB of a sub-DB */
unsigned int md_dirty; /**< TRUE if DB was written in this txn */
} MDB_dbx;
@ -923,15 +924,6 @@ mdb_cmp(MDB_txn *txn, MDB_dbi dbi, const MDB_val *a, const MDB_val *b)
return txn->mt_dbxs[dbi].md_cmp(a, b);
}
/** Compare two data items according to a particular database.
* This returns a comparison as if the two items were data items of
* a sorted duplicates #MDB_DUPSORT database.
* @param[in] txn A transaction handle returned by #mdb_txn_begin()
* @param[in] dbi A database handle returned by #mdb_open()
* @param[in] a The first item to compare
* @param[in] b The second item to compare
* @return < 0 if a < b, 0 if a == b, > 0 if a > b
*/
int
mdb_dcmp(MDB_txn *txn, MDB_dbi dbi, const MDB_val *a, const MDB_val *b)
{
@ -4731,4 +4723,13 @@ int mdb_set_relfunc(MDB_txn *txn, MDB_dbi dbi, MDB_rel_func *rel)
return MDB_SUCCESS;
}
int mdb_set_relctx(MDB_txn *txn, MDB_dbi dbi, void *ctx)
{
if (txn == NULL || !dbi || dbi >= txn->mt_numdbs)
return EINVAL;
txn->mt_dbxs[dbi].md_relctx = ctx;
return MDB_SUCCESS;
}
/** @} */

51
libraries/libmdb/mdb.h
Unescape View File

@ -125,13 +125,18 @@ typedef struct MDB_val {
typedef int (MDB_cmp_func)(const MDB_val *a, const MDB_val *b);
/** A callback function used to relocate a position-dependent data item
* in a fixed-address database. The \b newptr gives the item's current address in
* the memory map, and \b oldptr gives its previous address. This callback is
* expected to walk through the fields of the record in newptr and modify any
* in a fixed-address database. The \b newptr gives the item's desired address in
* the memory map, and \b oldptr gives its previous address. The item's actual
* data resides at the address in \b item. This callback is expected to walk
* through the fields of the record in \b item and modify any
* values based at the \b oldptr address to be relative to the \b newptr address.
* @param[in,out] item The item that is to be relocated.
* @param[in] oldptr The previous address.
* @param[in] newptr The new address to relocate to.
* @param[in] relctx An application-provided context, set by #mdb_set_relctx().
* @todo This feature is currently unimplemented.
*/
typedef void (MDB_rel_func)(void *newptr, void *oldptr, size_t size);
typedef void (MDB_rel_func)(MDB_val *item, void *oldptr, void *newptr, void *relctx);
/** @defgroup mdb_env Environment Flags
* @{
@ -178,7 +183,10 @@ typedef void (MDB_rel_func)(void *newptr, void *oldptr, size_t size);
#define MDB_CURRENT 0x40
/* @} */
/** Cursor operations */
/** Cursor Get operations
* This is the set of all operations for retrieving data
* using a cursor.
*/
typedef enum MDB_cursor_op {
MDB_FIRST, /**< Position at first key/data item */
MDB_FIRST_DUP, /**< Position at first data item of current key.
@ -596,8 +604,8 @@ void mdb_close(MDB_txn *txn, MDB_dbi dbi);
* with #mdb_open(), the keys are compared lexically, with shorter keys collating
* before longer keys.
* @warning This function must be called before any data access functions are used,
* otherwise data corruption may occur. The same function must be used by every
* process accessing the database, every time the database is used.
* otherwise data corruption may occur. The same comparison function must be used by every
* program accessing the database, every time the database is used.
* @param[in] txn A transaction handle returned by #mdb_txn_begin()
* @param[in] dbi A database handle returned by #mdb_open()
* @param[in] cmp A #MDB_cmp_func function
@ -618,8 +626,8 @@ int mdb_set_compare(MDB_txn *txn, MDB_dbi dbi, MDB_cmp_func *cmp);
* with #mdb_open(), the data items are compared lexically, with shorter items collating
* before longer items.
* @warning This function must be called before any data access functions are used,
* otherwise data corruption may occur. The same function must be used by every
* process accessing the database, every time the database is used.
* otherwise data corruption may occur. The same comparison function must be used by every
* program accessing the database, every time the database is used.
* @param[in] txn A transaction handle returned by #mdb_txn_begin()
* @param[in] dbi A database handle returned by #mdb_open()
* @param[in] cmp A #MDB_cmp_func function
@ -650,6 +658,21 @@ int mdb_set_dupsort(MDB_txn *txn, MDB_dbi dbi, MDB_cmp_func *cmp);
*/
int mdb_set_relfunc(MDB_txn *txn, MDB_dbi dbi, MDB_rel_func *rel);
/** Set a context pointer for a #MDB_FIXEDMAP database's relocation function.
* See #mdb_set_relfunc and #MDB_rel_func for more details.
* @param[in] txn A transaction handle returned by #mdb_txn_begin()
* @param[in] dbi A database handle returned by #mdb_open()
* @param[in] ctx An arbitrary pointer for whatever the application needs.
* It will be passed to the callback function set by #mdb_set_relfunc
* as its \b relctx parameter whenever the callback is invoked.
* @return A non-zero error value on failure and 0 on success. Some possible
* errors are:
* <ul>
* <li>EINVAL - an invalid parameter was specified.
* </ul>
*/
int mdb_set_relctx(MDB_txn *txn, MDB_dbi dbi, void *ctx);
/** Get items from a database.
* This function retrieves key/data pairs from the database. The address
* and length of the data associated with the specified \b key are returned
@ -852,5 +875,15 @@ int mdb_cursor_count(MDB_cursor *cursor, size_t *countp);
*/
int mdb_cmp(MDB_txn *txn, MDB_dbi dbi, const MDB_val *a, const MDB_val *b);
/** Compare two data items according to a particular database.
* This returns a comparison as if the two items were data items of
* a sorted duplicates #MDB_DUPSORT database.
* @param[in] txn A transaction handle returned by #mdb_txn_begin()
* @param[in] dbi A database handle returned by #mdb_open()
* @param[in] a The first item to compare
* @param[in] b The second item to compare
* @return < 0 if a < b, 0 if a == b, > 0 if a > b
*/
int mdb_dcmp(MDB_txn *txn, MDB_dbi dbi, const MDB_val *a, const MDB_val *b);
/** @} */
#endif /* _MDB_H_ */

Write Preview
Loading…
Cancel
Save