pbl.h

B树算法实现

#ifndef _PBL_H_
#define _PBL_H_
/*
 pbl.h - external include file of library

 Copyright (C) 2002    Peter Graf

   This file is part of PBL - The Program Base Library.
   PBL is free software.

    This library is free software; you can redistribute it and/or
    modify it under the terms of the GNU Lesser General Public
    License as published by the Free Software Foundation; either
    version 2.1 of the License, or (at your option) any later version.

    This library is distributed in the hope that it will be useful,
    but WITHOUT ANY WARRANTY; without even the implied warranty of
    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
    Lesser General Public License for more details.

    You should have received a copy of the GNU Lesser General Public
    License along with this library; if not, write to the Free Software
    Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA

   For more information on the Program Base Library or Peter Graf,
   please see: http://mission.base.com/.

    $Log: pbl.h,v $
    Revision 1.2  2002/09/12 20:47:18  peter
    added the isam file handling to the library

    Revision 1.1  2002/09/05 13:44:12  peter
    Initial revision


*/

#ifdef __cplusplus
extern "C" {
#endif

/*
 * make sure "strings <exe> | grep Id | sort -u" shows the source file versions
 */
static char* _PBL_H_id = "$Id: pbl.h,v 1.2 2002/09/12 20:47:18 peter Exp $";
static int   _PBL_H_fct() { return( _PBL_H_id ? 0 : _PBL_H_fct() ); }

#ifdef WIN32
    #include <direct.h>
    #include <io.h>
#else
    #include <sys/dir.h>
#endif

/*****************************************************************************/
/* #defines                                                                  */
/*****************************************************************************/

#ifdef _WIN32

/*
 * some functions have strange names on windows
 */
#define strcasecmp   _stricmp
#define strncasecmp  _strnicmp
#define snprintf     _snprintf

#else

#ifndef O_BINARY
#define O_BINARY     0
#endif

#endif

#define PBL_ERRSTR_LEN                    2048

/** @name B: Files
 *  list of files of component
 *  <P>
 *  <B>FILES</B>
 *  <UL>
 *  <LI> <a href="../pbl.h">pbl.h</a> - the include file of the library
 *  <LI> <a href="../pbl.c">pbl.c</a> - source for the base functions
 *  <LI> <a href="../pblhash.c">pblhash.c</a> - source file for the
 *                                              hash functions
 *  <LI> <a href="../pblhttst.c">pblhttst.c</a> - source file for the
 *                                              hash function test frame
 *  <LI> <a href="../pblkf.c">pblkf.c</a> - source file for the key
 *                                              file functions
 *  <LI> <a href="../pblkftst.c">pblkftst.c</a> - source file for the
 *                                              key file handling test frame
 *  <LI> <a href="../pblisam.c">pblisam.c</a> - source file for the isam
 *                                              file functions
 *  <LI> <a href="../pbliftst.c">pbliftst.c</a> - source file for the
 *                                              isam file handling test frame
 *  <LI> <a href="../makefile">makefile</a> - a Unix makefile for the
 *                                              component
 *  <LI> <a href="../pblhttstdeb.dsp">pblhttstdeb.dsp</a> - a Microsoft Visual
 *                                              Studio 6.0 project file for
 *                                              hash table debug
 *  <LI> <a href="../pblkftstdeb.dsp">pblkftstdeb.dsp</a> - a Microsoft
 *                                              Visual Studio 6.0 project file
 *                                              for key file debug
 *  <LI> <a href="../pbliftstdeb.dsp">pbliftstdeb.dsp</a> - a Microsoft Visual
 *                                              Studio 6.0 project file for
 *                                              isam file debug
 *  <LI> <a href="../ISAM0001.LOG">ISAM0001.LOG</a> - a test case for the 
 *                                              isam file handling test frame
 *  <LI> <a href="../pbl.dxx">pbl.dxx</a> - the source for this document
 *  </UL>
 */

#define PBL_FILE_LIST

/** @name C: Error codes
 *  error codes of the pbl library
 *
 *  @field PBL_ERROR_OUT_OF_MEMORY out of memory
 *  @field PBL_ERROR_EXISTS        record already exists
 *  @field PBL_ERROR_NOT_FOUND     record not found
 *  @field PBL_ERROR_BAD_FILE      file structure damaged
 *  @field PBL_ERROR_PARAM_MODE    parameter mode is not valid
 *  @field PBL_ERROR_PARAM_KEY     parameter key is not valid
 *  @field PBL_ERROR_PARAM_KEYLEN  parameter keylen is not valid
 *  @field PBL_ERROR_PARAM_DATA    parameter data is not valid
 *  @field PBL_ERROR_PARAM_DATALEN parameter datalen is not valid
 *  @field PBL_ERROR_PARAM_INDEX   parameter index is not valid
 *  @field PBL_ERROR_CREATE        file system create error, see errno
 *  @field PBL_ERROR_OPEN          file system open error, see errno
 *  @field PBL_ERROR_SEEK          file system seek error, see errno
 *  @field PBL_ERROR_READ          file system read error, see errno
 *  @field PBL_ERROR_WRITE         file system write error, see errno
 *  @field PBL_ERROR_PROGRAM       an internal error in the code, debug it!!
 *  @field PBL_ERROR_NOFIT         internal error forcing a block split
 *  @field PBL_ERROR_NOT_ALLOWED file not open for update, operation not allowed
 *  @field PBL_ERROR_POSITION    current record is not positioned
 */
#define PBL_ERROR_BASE                    1000

#define PBL_ERROR_OUT_OF_MEMORY           ( PBL_ERROR_BASE + 1 )
#define PBL_ERROR_EXISTS                  ( PBL_ERROR_BASE + 2 )
#define PBL_ERROR_NOT_FOUND               ( PBL_ERROR_BASE + 3 )
#define PBL_ERROR_BAD_FILE                ( PBL_ERROR_BASE + 4 )
#define PBL_ERROR_PARAM_MODE              ( PBL_ERROR_BASE + 5 )
#define PBL_ERROR_PARAM_KEY               ( PBL_ERROR_BASE + 6 )
#define PBL_ERROR_PARAM_KEYLEN            ( PBL_ERROR_BASE + 7 )
#define PBL_ERROR_PARAM_DATA              ( PBL_ERROR_BASE + 8 )
#define PBL_ERROR_PARAM_DATALEN           ( PBL_ERROR_BASE + 9 )
#define PBL_ERROR_PARAM_INDEX             ( PBL_ERROR_BASE + 10 )

#define PBL_ERROR_CREATE                  ( PBL_ERROR_BASE + 20 )
#define PBL_ERROR_OPEN                    ( PBL_ERROR_BASE + 21 )
#define PBL_ERROR_SEEK                    ( PBL_ERROR_BASE + 22 )
#define PBL_ERROR_READ                    ( PBL_ERROR_BASE + 23 )
#define PBL_ERROR_WRITE                   ( PBL_ERROR_BASE + 24 )

#define PBL_ERROR_PROGRAM                 ( PBL_ERROR_BASE + 30 )
#define PBL_ERROR_NOFIT                   ( PBL_ERROR_BASE + 31 )

#define PBL_ERROR_NOT_ALLOWED             ( PBL_ERROR_BASE + 40 )
#define PBL_ERROR_POSITION                ( PBL_ERROR_BASE + 41 )

/** @name D: Definitions for Key File Parameters
  * DEFINES FOR PARAMETER <B> mode </B> OF \Ref{pblKfFind}()
  * @field PBLEQ                   any record that is equal
  * @field PBLFI                   first record that is equal
  * @field PBLLA                   last record that is equal
  * @field PBLGE                   last equal or first that is greater
  * @field PBLGT                   first that is greater
  * @field PBLLE                   first equal or last that is smaller
  * @field PBLLT                   last that is smaller
  */
#define PBLEQ               1
#define PBLFI               2
#define PBLLA               3
#define PBLGE               4
#define PBLGT               5
#define PBLLE               6
#define PBLLT               7

/** @name E: Definitions for ISAM Parameters
  * DEFINES FOR PARAMETER <B> which </B> OF \Ref{pblIsamGet}()
  * @field PBLTHIS                  get key and keylen of current record
  * @field PBLNEXT                  get key and keylen of next record
  * @field PBLPREV                  get key and keylen of previous record
  * @field PBLFIRST                 get key and keylen of first record
  * @field PBLLAST                  get key and keylen of last record
 */
#define PBLTHIS             1
#define PBLNEXT             2
#define PBLPREV             3
#define PBLFIRST            4
#define PBLLAST             5

/**
 * the maximum length of a key of the key file component,
 * @doc maximum length of a key, 255 for now
 */
#define PBLKEYLENGTH      255

/**
 * maximum data length of data being stored on index blocks of key files,
 * @doc maximum length of data stored with an item on the level 0 block, 1024
 * @doc data that is longer is stored on data blocks.
 */
#define PBLDATALENGTH    1024

/*****************************************************************************/
/* macros                                                                    */
/*****************************************************************************/

/*
 * The PBL_MEMTRACE define can be used for debugging the library,
 * if defined the library will log a line for all memory chunks
 * that are allocated for more than 3 minutes into the file ./pblmemtrace.log
 *
 * This can be used to detect heap memory lost by the code.
 * See also function pbl_memtrace_out in pbl.c
 */
 
/* #define PBL_MEMTRACE */
#ifdef  PBL_MEMTRACE

extern void pbl_memtrace_delete( void * data );
extern void pbl_memtrace_out( int checktime );

#define PBL_FREE( ptr ) if( ptr ){ pbl_memtrace_delete( ptr );\
                                   free( ptr ); ptr = 0; }

#else

/**
 * make free save against NULL pointers,
 * @doc also the parameter ptr is set to NULL
 */
#define PBL_FREE( ptr ) if( ptr ){ free( ptr ); ptr = 0; }

#endif

/**
 * macros for linear list handling,
 */
#define PBL_LIST_( Parameters )

/**
  * push an element to the beginning of a linear list
  */
#define PBL_LIST_PUSH( HEAD, TAIL, ITEM, NEXT, PREV )\
{\
    (ITEM)->PREV = 0;\
    if(( (ITEM)->NEXT = (HEAD) ))\
        { (ITEM)->NEXT->PREV = (ITEM); }\
    else\
        { (TAIL) = (ITEM); }\
    (HEAD) = (ITEM);\
}

/**
  * append an element to the end of a linear list
  */
#define PBL_LIST_APPEND( HEAD, TAIL, ITEM, NEXT, PREV )\
                         PBL_LIST_PUSH( TAIL, HEAD, ITEM, PREV, NEXT )

/**
  * remove an element from a linear list
  */
#define PBL_LIST_UNLINK( HEAD, TAIL, ITEM, NEXT, PREV )\
{\
    if( (ITEM)->NEXT )\