mco.h

extremeDB s sample code,useful for you

/*******************************************************************
 *                                                                 *
 *  mco.h                                                          *
 *                                                                 *
 *  This file is a part of the eXtremeDB source code               *
 *  Copyright (c) 2001-2006 McObject LLC                           * 
 *  All Rights Reserved                                            *
 *                                                                 *
 *  eXtremeDB runtime public definitions and static API            * 
 *                                                                 *
 ***************************************************************** */
#ifndef MCO_MCO_H__
#define MCO_MCO_H__

#ifdef __cplusplus
extern "C" { 
#endif

//#define MCO_CFG_CHECKLEVEL_1
#include "mcospec.h"

typedef enum MCO_RET_E_  /* return codes */
{ 
  MCO_S_OK                 =  0, /* success  */
  MCO_S_BUSY               =  1, /* the instance is busy */
  MCO_S_NOTFOUND           = 10, /* search operation failed */
  MCO_S_CURSOR_END         = 11, /* cursor cannot be moved */
  MCO_S_CURSOR_EMPTY       = 12, /* no objects in index */
  MCO_S_DUPLICATE          = 13, /* index restriction violated */
  MCO_S_EVENT_RELEASED     = 14, /* waiting thread was released */

  MCO_E_INVALID_HANDLE     = 51, /* normally invalid handle produces fatal error. This code returned by special checks. */
  MCO_E_NOMEM              = 52, /* no memory */
  MCO_E_ACCESS             = 53, /* trying to use read only transaction for write */
  MCO_E_TRANSACT           = 54, /* transaction is in error state */
  MCO_E_INDEXLIMIT         = 55, /* vector index out of bounds */
  MCO_E_EMPTYVECTOREL      = 56, /* vector element was not set (at given index) */
  MCO_E_UNSUPPORTED        = 57, /* resize vector, blob update etc. */
  MCO_E_EMPTYOPTIONAL      = 58, /* optional was not set */
  MCO_E_EMPTYBLOB          = 59, /* trying to read blob, which was not written */
  MCO_E_CURSOR_INVALID     = 60, /* cursor is not valid */
  MCO_E_ILLEGAL_TYPE       = 61, /* search by oid: type is not that was expected */
  MCO_E_ILLEGAL_PARAM      = 62, /* e.g. illegal search operation code */
  MCO_E_CURSOR_MISMATCH    = 63, /* cursor type and object type are incompatible */
  MCO_E_DELETED            = 65, /* trying to update object, deleted in current transaction */
  MCO_E_LONG_TRANSACTON    = 66, /* transaction length is more then MCO_TRN_MAXLENGTH */
  MCO_E_INSTANCE_DUPLICATE = 67, /* attempt to create db instance with duplicate name */
  MCO_E_UPGRADE_FAILED     = 68, /* simultaneous upgrades may not be not possible */
  MCO_E_NOINSTANCE         = 69, /* db instance not found */
  MCO_E_OPENED_SESSIONS    = 70, /* failed to close db: have opened sessions */
  MCO_E_PAGESIZE           = 71, /* page size is not acceptable */
  MCO_E_WRITE_STREAM       = 75, /* write stream failure */
  MCO_E_READ_STREAM        = 76, /* read stream failure  */
  MCO_E_LOAD_DICT          = 77, /* db load: dictionary differs */
  MCO_E_LOAD_DATA          = 78, /* error data when loading db */
  MCO_E_VERS_MISMATCH      = 79, /* version mismatch */
  MCO_E_VOLUNTARY_NOT_EXIST= 80, /* voluntary index is not created */
  MCO_E_EXCLUSIVE_MODE     = 81, /* db is in the exclusive mode; try later */
  MCO_E_MAXEXTENDS         = 82, /* maximum number of extends reached */
  MCO_E_HIST_OBJECT        = 83, /* operation is illegal for old version of the object */
  MCO_E_SHM_ERROR          = 84, /* failed to create/attach to shared memory */
  MCO_E_NOTINIT            = 85, /* runtime was not initialized */
  MCO_E_SESLIMIT           = 86, /* sessions number limit reached */
  MCO_E_INSTANCES_LIMIT    = 87, /* too many instances */
  MCO_E_MAXTRANSSIZE_LOCKED= 88, /* the maximum size of transaction cannot be changed */
  MCO_E_2PHASECOMMIT       = 89, /* 2-phase commit is in progress */ 

  MCO_E_EVAL               = 100, /* evaluation version limitaion */
  MCO_E_HA                 = 200, /* HA base error code */
  MCO_E_HAFRAMEWORK        = 250, /* HAFRAMEWORK base error code */
  MCO_E_LOG                = 300  /* LOG base error code */
} 
MCO_RET; /* return code */



#define mco_trans_size       20  /* max number of updated or deleted objects in one transaction */

#ifdef MCO_PLATFORM_X64

#define mco_min_page_size    136  /* min size of a page    */
#define mco_cursor_size      136  /* cursor structure size */
#define mco_handle_size      48  /* object handle size    */

#else //MCO_PLATFORM_X64

#define mco_min_page_size    64  /* min size of a page    */
#define mco_cursor_size      48  /* cursor structure size */
#define mco_handle_size      24  /* object handle size    */

#endif //MCO_PLATFORM_X64

#define mco_handle_size_w    ( mco_handle_size / sizeof(void *) )
#define mco_cursor_size_w    ( mco_cursor_size / sizeof(void *) )

typedef void * MCO_Hf [ mco_handle_size_w ]; 

typedef struct mco_cursor_t_
{
  void * c[mco_cursor_size_w];
}
  mco_cursor_t,       /* cursor (structure)            */
* mco_cursor_h;       /* cursor handle (pointer)       */

#ifdef MCO_NO_FORWARDS

typedef void * mco_trans_h;
typedef void * mco_db_h;
typedef void * mco_dictionary_h;

#else

struct mco_trans_t_;      typedef struct mco_trans_t_ *
mco_trans_h;          /* transaction handle (pointer)  */

struct mco_db_t_;         typedef struct mco_db_t_ *
mco_db_h;             /* database handle (pointer)     */

struct mco_dictionary_t_; typedef struct mco_dictionary_t_ *
mco_dictionary_h;     /* dictionary handle (pointer)   */

#endif

/* transaction priority values */

typedef enum MCO_TRANS_PRIORITY_E_
{
  MCO_TRANS_IDLE          = 1,
  MCO_TRANS_BACKGROUND    = 2,
  MCO_TRANS_FOREGROUND    = 3,
  MCO_TRANS_HIGH          = 4,
  MCO_TRANS_ISR           = 77
}
MCO_TRANS_PRIORITY;

/* transaction types values */
typedef enum MCO_TRANS_TYPE_E_
{
  MCO_READ_ONLY           = 0,
  MCO_READ_WRITE          = 1
}
MCO_TRANS_TYPE;

/* Database management */

/* sets the new maximum size of the transaction. MUST be called after
   mco_runtime_start() and  before mco_db_open (...)  */
MCO_RET     mco_set_maxtranssize ( uint4 ); 

MCO_RET     mco_runtime_start   ( void ); 
MCO_RET     mco_runtime_stop    ( void );
MCO_RET     mco_close_all_instances( void ); /* for multiprocessing only */

/* depending on configuration,
   database is created in process's memory (address is specified),
   or in shared memory (in this case shared memory is acquired
   by database, and address used as "hint"; db_name used to construct shared memory id)
 */
MCO_RET	    mco_db_open         ( const char * db_name, mco_dictionary_h dict, void * mem_ptr, mco_puint total_size, uint2 page_size);

/* extend cannot be called in shared memory mode */
MCO_RET     mco_db_extend       ( const char * db_name, void * mem_ptr, mco_puint size );

MCO_RET     mco_db_close        ( const char * db_name);
MCO_RET     mco_db_kill         ( const char * db_name);

MCO_RET     mco_db_connect      ( const char * dbname, /*OUT*/ mco_db_h * pdb );
MCO_RET     mco_db_disconnect   ( mco_db_h db );

MCO_RET     mco_db_free_pages   ( mco_db_h db, /*OUT*/ mco_puint * retvalue);
MCO_RET     mco_db_total_pages  ( mco_db_h db, /*OUT*/ mco_puint * retvalue);
MCO_RET     mco_db_page_size    ( mco_db_h db, /*OUT*/ uint2 * retvalue);
MCO_RET     mco_db_check_memory ( mco_db_h db );


/* Transaction management */
MCO_RET     mco_trans_start     ( mco_db_h db, MCO_TRANS_TYPE type, MCO_TRANS_PRIORITY pri, /*OUT*/ mco_trans_h * p_trans ); 
MCO_RET	    mco_trans_upgrade   ( mco_trans_h t);
MCO_RET     mco_trans_commit    ( mco_trans_h t);
MCO_RET     mco_trans_rollback  ( mco_trans_h t);
MCO_RET     mco_trans_type      ( mco_trans_h t, /*OUT*/ MCO_TRANS_TYPE * type);
MCO_RET     mco_get_last_error  ( mco_trans_h t);
MCO_RET  mco_trans_commit_phase1( mco_trans_h t );
MCO_RET  mco_trans_commit_phase2( mco_trans_h t );

/* Cursor-based */	
typedef enum MCO_OPCODE_E_ 
{ 
  MCO_LT        = 1, 
  MCO_LE        = 2, 
  MCO_EQ        = 3, 
  MCO_GE        = 4, 
  MCO_GT        = 5 
} 
MCO_OPCODE; 


/* cursor navigation */


MCO_RET	    mco_cursor_check    ( mco_trans_h t, mco_cursor_h c); 
MCO_RET	    mco_cursor_first	( mco_trans_h t, /*INOUT*/ mco_cursor_h c); 
MCO_RET	    mco_cursor_last     ( mco_trans_h t, /*INOUT*/ mco_cursor_h c); 
MCO_RET	    mco_cursor_next		  ( mco_trans_h t, /*INOUT*/ mco_cursor_h c); 
MCO_RET	    mco_cursor_prev		  ( mco_trans_h t, /*INOUT*/ mco_cursor_h c); 

/* cursor types */
typedef enum MCO_CURSOR_TYPE_E_
{
  MCO_LIST_CURSOR         = 0,
  MCO_TREE_CURSOR         = 1,
  MCO_HASH_CURSOR         = 2
}
MCO_CURSOR_TYPE;


MCO_RET     mco_cursor_type             ( mco_cursor_h c, /*OUT*/ MCO_CURSOR_TYPE * type ); 
MCO_RET     mco_cursor_get_class_code   ( mco_cursor_h c, /*OUT*/ uint2 *rescode );



/* statistics */

/* statistics for a class, index pages are not counted here */
typedef struct mco_class_stat_t_ 
{
  uint4     objects_num;
  uint4     core_pages;  /* pages used for all data except blobs */
  uint4     blob_pages;  /* pages used by blobs */
  mco_puint core_space;  /* in bytes, not counting blobs */
}
  mco_class_stat_t,
* mco_class_stat_h;