Return to test_multiplex.h CVS log

Up to [ELWIX - Embedded LightWeight unIX -] / embedaddon / sqlite3 / src

sqlite3

    1: /*
    2: ** 2011 March 18
    3: **
    4: ** The author disclaims copyright to this source code.  In place of
    5: ** a legal notice, here is a blessing:
    6: **
    7: **    May you do good and not evil.
    8: **    May you find forgiveness for yourself and forgive others.
    9: **    May you share freely, never taking more than you give.
   10: **
   11: *************************************************************************
   12: **
   13: ** This file contains a VFS "shim" - a layer that sits in between the
   14: ** pager and the real VFS.
   15: **
   16: ** This particular shim enforces a multiplex system on DB files.  
   17: ** This shim shards/partitions a single DB file into smaller 
   18: ** "chunks" such that the total DB file size may exceed the maximum
   19: ** file size of the underlying file system.
   20: **
   21: */
   22: 
   23: #ifndef _TEST_MULTIPLEX_H
   24: #define _TEST_MULTIPLEX_H
   25: 
   26: /*
   27: ** CAPI: File-control Operations Supported by Multiplex VFS
   28: **
   29: ** Values interpreted by the xFileControl method of a Multiplex VFS db file-handle.
   30: **
   31: ** MULTIPLEX_CTRL_ENABLE:
   32: **   This file control is used to enable or disable the multiplex
   33: **   shim.
   34: **
   35: ** MULTIPLEX_CTRL_SET_CHUNK_SIZE:
   36: **   This file control is used to set the maximum allowed chunk 
   37: **   size for a multiplex file set.  The chunk size should be 
   38: **   a multiple of SQLITE_MAX_PAGE_SIZE, and will be rounded up
   39: **   if not.
   40: **
   41: ** MULTIPLEX_CTRL_SET_MAX_CHUNKS:
   42: **   This file control is used to set the maximum number of chunks
   43: **   allowed to be used for a mutliplex file set.
   44: */
   45: #define MULTIPLEX_CTRL_ENABLE          214014
   46: #define MULTIPLEX_CTRL_SET_CHUNK_SIZE  214015
   47: #define MULTIPLEX_CTRL_SET_MAX_CHUNKS  214016
   48: 
   49: /*
   50: ** CAPI: Initialize the multiplex VFS shim - sqlite3_multiplex_initialize()
   51: **
   52: ** Use the VFS named zOrigVfsName as the VFS that does the actual work.  
   53: ** Use the default if zOrigVfsName==NULL.  
   54: **
   55: ** The multiplex VFS shim is named "multiplex".  It will become the default
   56: ** VFS if makeDefault is non-zero.
   57: **
   58: ** An auto-extension is registered which will make the function 
   59: ** multiplex_control() available to database connections.  This
   60: ** function gives access to the xFileControl interface of the 
   61: ** multiplex VFS shim.
   62: **
   63: ** SELECT multiplex_control(<op>,<val>);
   64: ** 
   65: **   <op>=1 MULTIPLEX_CTRL_ENABLE
   66: **   <val>=0 disable
   67: **   <val>=1 enable
   68: ** 
   69: **   <op>=2 MULTIPLEX_CTRL_SET_CHUNK_SIZE
   70: **   <val> int, chunk size
   71: ** 
   72: **   <op>=3 MULTIPLEX_CTRL_SET_MAX_CHUNKS
   73: **   <val> int, max chunks
   74: **
   75: ** THIS ROUTINE IS NOT THREADSAFE.  Call this routine exactly once
   76: ** during start-up.
   77: */
   78: extern int sqlite3_multiplex_initialize(const char *zOrigVfsName, int makeDefault);
   79: 
   80: /*
   81: ** CAPI: Shutdown the multiplex system - sqlite3_multiplex_shutdown()
   82: **
   83: ** All SQLite database connections must be closed before calling this
   84: ** routine.
   85: **
   86: ** THIS ROUTINE IS NOT THREADSAFE.  Call this routine exactly once while
   87: ** shutting down in order to free all remaining multiplex groups.
   88: */
   89: extern int sqlite3_multiplex_shutdown(void);
   90: 
   91: #endif