SQLite

/************************ Shim Definitions ******************************/

#define SQLITE_MULTIPLEX_VFS_NAME "multiplex"

/* This is the limit on the chunk size.  It may be changed by calling
** the xFileControl() interface.  It will be rounded up to a 
** multiple of SQLITE_MAX_PAGE_SIZE.  We default it here to 1GB.
*/
#define SQLITE_MULTIPLEX_CHUNK_SIZE (SQLITE_MAX_PAGE_SIZE*16384)

/* Default limit on number of chunks.  Care should be taken
** so that values for chunks numbers fit in the SQLITE_MULTIPLEX_EXT_FMT
** format specifier. It may be changed by calling
** the xFileControl() interface.
*/
#define SQLITE_MULTIPLEX_MAX_CHUNKS 32

  if( pGroup==0 ){
    rc=SQLITE_NOMEM;
  }else{
    /* assign pointers to extra space allocated */
    char *p = (char *)&pGroup[1];
    pMultiplexOpen->pGroup = pGroup;
    memset(pGroup, 0, sz);
    pGroup->bEnabled = -1;
    pGroup->nChunkSize = SQLITE_MULTIPLEX_CHUNK_SIZE;
    pGroup->nMaxChunks = SQLITE_MULTIPLEX_MAX_CHUNKS;
    pGroup->pReal = (sqlite3_file **)p;
    p += (sizeof(sqlite3_file *)*pGroup->nMaxChunks);
    for(i=0; i<pGroup->nMaxChunks; i++){
      pGroup->pReal[i] = (sqlite3_file *)p;
      p += pOrigVfs->szOsFile;
    }
    /* bOpen[] vals should all be zero from memset above */
    pGroup->bOpen = p;
    p += pGroup->nMaxChunks;
    pGroup->zName = p;
    /* save off base filename, name length, and original open flags  */
    memcpy(pGroup->zName, zName, nName+1);
    pGroup->nName = nName;
    pGroup->flags = flags;
    pSubOpen = multiplexSubOpen(pMultiplexOpen, 0, &rc, pOutFlags);
    if( pSubOpen ){
      /* if this file is already larger than chunk size, disable 
      ** the multiplex feature.
      */
      sqlite3_int64 sz;
      int rc2 = pSubOpen->pMethods->xFileSize(pSubOpen, &sz);
      if( (rc2==SQLITE_OK) && (sz>pGroup->nChunkSize) ){
        pGroup->bEnabled = 0;
      }
      if( pSubOpen->pMethods->iVersion==1 ){
        pMultiplexOpen->base.pMethods = &gMultiplex.sIoMethodsV1;
      }else{
        pMultiplexOpen->base.pMethods = &gMultiplex.sIoMethodsV2;
      }
      /* place this group at the head of our list */
      pGroup->pNext = gMultiplex.pGroups;

  int iAmt,
  sqlite3_int64 iOfst
){
  multiplexConn *p = (multiplexConn*)pConn;
  multiplexGroup *pGroup = p->pGroup;
  int rc = SQLITE_OK;
  multiplexEnter();
  if( !pGroup->bEnabled ){
    sqlite3_file *pSubOpen = multiplexSubOpen(p, 0, &rc, NULL);
    rc = ( !pSubOpen ) ? SQLITE_IOERR_READ : pSubOpen->pMethods->xRead(pSubOpen, pBuf, iAmt, iOfst);
  }else{
    while( iAmt > 0 ){
      int i = (int)(iOfst / pGroup->nChunkSize);
      sqlite3_file *pSubOpen = multiplexSubOpen(p, i, &rc, NULL);
      if( pSubOpen ){
        int extra = ((int)(iOfst % pGroup->nChunkSize) + iAmt) - pGroup->nChunkSize;
        if( extra<0 ) extra = 0;
        iAmt -= extra;
        rc = pSubOpen->pMethods->xRead(pSubOpen, pBuf, iAmt, iOfst % pGroup->nChunkSize);
        if( rc!=SQLITE_OK ) break;
        pBuf = (char *)pBuf + iAmt;
        iOfst += iAmt;
        iAmt = extra;
      }else{
        rc = SQLITE_IOERR_READ;
        break;
      }
    }
  }
  multiplexLeave();
  return rc;
}

/* Pass xWrite requests thru to the original VFS after
** determining the correct chunk to operate on.
** Break up writes across chunk boundaries.
*/
static int multiplexWrite(
  sqlite3_file *pConn,
  const void *pBuf,
  int iAmt,
  sqlite3_int64 iOfst
){
  multiplexConn *p = (multiplexConn*)pConn;
  multiplexGroup *pGroup = p->pGroup;
  int rc = SQLITE_OK;
  multiplexEnter();
  if( !pGroup->bEnabled ){
    sqlite3_file *pSubOpen = multiplexSubOpen(p, 0, &rc, NULL);
    rc = ( !pSubOpen ) ? SQLITE_IOERR_WRITE : pSubOpen->pMethods->xWrite(pSubOpen, pBuf, iAmt, iOfst);
  }else{
    while( iAmt > 0 ){
      int i = (int)(iOfst / pGroup->nChunkSize);
      sqlite3_file *pSubOpen = multiplexSubOpen(p, i, &rc, NULL);
      if( pSubOpen ){
        int extra = ((int)(iOfst % pGroup->nChunkSize) + iAmt) - pGroup->nChunkSize;
        if( extra<0 ) extra = 0;
        iAmt -= extra;
        rc = pSubOpen->pMethods->xWrite(pSubOpen, pBuf, iAmt, iOfst % pGroup->nChunkSize);
        if( rc!=SQLITE_OK ) break;
        pBuf = (char *)pBuf + iAmt;
        iOfst += iAmt;
        iAmt = extra;
      }else{
        rc = SQLITE_IOERR_WRITE;
        break;
      }
    }
  }
  multiplexLeave();
  return rc;
}

/* Pass xTruncate requests thru to the original VFS after
** determining the correct chunk to operate on.  Delete any
** chunks above the truncate mark.
*/
static int multiplexTruncate(sqlite3_file *pConn, sqlite3_int64 size){
  multiplexConn *p = (multiplexConn*)pConn;
  multiplexGroup *pGroup = p->pGroup;
  int rc = SQLITE_OK;
  multiplexEnter();
  if( !pGroup->bEnabled ){
    sqlite3_file *pSubOpen = multiplexSubOpen(p, 0, &rc, NULL);
    rc = ( !pSubOpen ) ? SQLITE_IOERR_TRUNCATE : pSubOpen->pMethods->xTruncate(pSubOpen, size);
  }else{
    int rc2;
    int i;
    sqlite3_file *pSubOpen;
    sqlite3_vfs *pOrigVfs = gMultiplex.pOrigVfs;   /* Real VFS */

    memcpy(gMultiplex.zName, pGroup->zName, pGroup->nName+1);
    /* delete the chunks above the truncate limit */
    for(i=(int)(size / pGroup->nChunkSize)+1; i<pGroup->nMaxChunks; i++){
      /* close any open chunks before deleting them */
      if( pGroup->bOpen[i] ){
        pSubOpen = pGroup->pReal[i];
        rc2 = pSubOpen->pMethods->xClose(pSubOpen);
        if( rc2!=SQLITE_OK ) rc = SQLITE_IOERR_TRUNCATE;
        pGroup->bOpen[i] = 0;
      }
#ifdef SQLITE_MULTIPLEX_EXT_OVWR
      sqlite3_snprintf(SQLITE_MULTIPLEX_EXT_SZ+1, gMultiplex.zName+pGroup->nName-SQLITE_MULTIPLEX_EXT_SZ, SQLITE_MULTIPLEX_EXT_FMT, i);
#else
      sqlite3_snprintf(SQLITE_MULTIPLEX_EXT_SZ+1, gMultiplex.zName+pGroup->nName, SQLITE_MULTIPLEX_EXT_FMT, i);
#endif
      rc2 = pOrigVfs->xDelete(pOrigVfs, gMultiplex.zName, 0);
      if( rc2!=SQLITE_OK ) rc = SQLITE_IOERR_TRUNCATE;
    }
    pSubOpen = multiplexSubOpen(p, (int)(size / pGroup->nChunkSize), &rc2, NULL);
    if( pSubOpen ){
      rc2 = pSubOpen->pMethods->xTruncate(pSubOpen, size % pGroup->nChunkSize);
      if( rc2!=SQLITE_OK ) rc = rc2;
    }else{
      rc = SQLITE_IOERR_TRUNCATE;
    }
  }
  multiplexLeave();
  return rc;
}

/* Pass xSync requests through to the original VFS without change
*/

static int multiplexFileSize(sqlite3_file *pConn, sqlite3_int64 *pSize){
  multiplexConn *p = (multiplexConn*)pConn;
  multiplexGroup *pGroup = p->pGroup;
  int rc = SQLITE_OK;
  int rc2;
  int i;
  multiplexEnter();
  if( !pGroup->bEnabled ){
    sqlite3_file *pSubOpen = multiplexSubOpen(p, 0, &rc, NULL);
    rc = ( !pSubOpen ) ? SQLITE_IOERR_FSTAT : pSubOpen->pMethods->xFileSize(pSubOpen, pSize);
  }else{
    *pSize = 0;
    for(i=0; i<pGroup->nMaxChunks; i++){
      sqlite3_file *pSubOpen = NULL;
      /* if not opened already, check to see if the chunk exists */
      if( pGroup->bOpen[i] ){
        pSubOpen = pGroup->pReal[i];
      }else{
        sqlite3_vfs *pOrigVfs = gMultiplex.pOrigVfs;   /* Real VFS */
        int exists = 0;
        memcpy(gMultiplex.zName, pGroup->zName, pGroup->nName+1);
        if( i ){
#ifdef SQLITE_MULTIPLEX_EXT_OVWR
          sqlite3_snprintf(SQLITE_MULTIPLEX_EXT_SZ+1, gMultiplex.zName+pGroup->nName-SQLITE_MULTIPLEX_EXT_SZ, SQLITE_MULTIPLEX_EXT_FMT, i);
#else
          sqlite3_snprintf(SQLITE_MULTIPLEX_EXT_SZ+1, gMultiplex.zName+pGroup->nName, SQLITE_MULTIPLEX_EXT_FMT, i);
#endif
        }
        rc2 = pOrigVfs->xAccess(pOrigVfs, gMultiplex.zName, SQLITE_ACCESS_EXISTS, &exists);
        if( rc2==SQLITE_OK && exists){
          /* if it exists, open it */
          pSubOpen = multiplexSubOpen(p, i, &rc, NULL);
        }else{
          /* stop at first "gap" */
          break;
        }
      }
      if( pSubOpen ){
        sqlite3_int64 sz;
        rc2 = pSubOpen->pMethods->xFileSize(pSubOpen, &sz);
        if( rc2!=SQLITE_OK ){
          rc = rc2;
        }else{
          if( sz>pGroup->nChunkSize ){
            rc = SQLITE_IOERR_FSTAT;
          }
          *pSize += sz;
        }
      }else{
        break;
      }
    }
  }
  multiplexLeave();
  return rc;
}

/* Pass xLock requests through to the original VFS unchanged.

  sqlite3_file *pSubOpen = multiplexSubOpen(p, 0, &rc, NULL);
  if( pSubOpen ){
    return pSubOpen->pMethods->xCheckReservedLock(pSubOpen, pResOut);
  }
  return SQLITE_IOERR_CHECKRESERVEDLOCK;
}

/* Pass xFileControl requests through to the original VFS unchanged,
** except for any MULTIPLEX_CTRL_* requests here.
*/
static int multiplexFileControl(sqlite3_file *pConn, int op, void *pArg){
  multiplexConn *p = (multiplexConn*)pConn;
  multiplexGroup *pGroup = p->pGroup;
  int rc = SQLITE_ERROR;
  sqlite3_file *pSubOpen;

  } aSub[] = {
    { "enable",       MULTIPLEX_CTRL_ENABLE,           1 },
    { "chunk_size",   MULTIPLEX_CTRL_SET_CHUNK_SIZE,   1 },
    { "max_chunks",   MULTIPLEX_CTRL_SET_MAX_CHUNKS,   1 },
    { 0, 0, 0 }
  };

  if( objc!=5 ){
    Tcl_WrongNumArgs(interp, 1, objv, "HANDLE DBNAME SUB-COMMAND INT-VALUE");
    return TCL_ERROR;
  }

  if( 0==Tcl_GetCommandInfo(interp, Tcl_GetString(objv[1]), &cmdInfo) ){
    Tcl_AppendResult(interp, "expected database handle, got \"", 0);
    Tcl_AppendResult(interp, Tcl_GetString(objv[1]), "\"", 0);
    return TCL_ERROR;
  }else{
    db = *(sqlite3 **)cmdInfo.objClientData;
  }

  rc = Tcl_GetIndexFromObjStruct(
      interp, objv[3], aSub, sizeof(aSub[0]), "sub-command", 0, &idx
  );
  if( rc!=TCL_OK ) return rc;

  switch( aSub[idx].argtype ){
    case 1:




      if( Tcl_GetIntFromObj(interp, objv[4], &iValue) ){
        return TCL_ERROR;
      }
      pArg = (void *)&iValue;
      break;
    default:
      Tcl_WrongNumArgs(interp, 4, objv, "SUB-COMMAND");

#***********************************************************************
#

set testdir [file dirname $argv0]
source $testdir/tester.tcl
source $testdir/malloc_common.tcl

set g_chunk_size [ expr ($::SQLITE_MAX_PAGE_SIZE*16384) ]
set g_max_chunks 32

# This handles appending the chunk number
# to the end of the filename.  if 
# SQLITE_MULTIPLEX_EXT_OVWR is defined, then
# it overwrites the last 2 bytes of the 
# file name with the chunk number.

do_test multiplex-1.4 { sqlite3_multiplex_shutdown }               {SQLITE_OK}

do_test multiplex-1.5 { sqlite3_multiplex_initialize "" 0 }        {SQLITE_OK}
do_test multiplex-1.6 { sqlite3_multiplex_shutdown }               {SQLITE_OK}
do_test multiplex-1.7 { sqlite3_multiplex_initialize "" 1 }        {SQLITE_OK}
do_test multiplex-1.8 { sqlite3_multiplex_shutdown }               {SQLITE_OK}


do_test multiplex-1.9.1  { sqlite3_multiplex_initialize "" 1 }     {SQLITE_OK}
do_test multiplex-1.9.2  { sqlite3 db test.db }                    {}
do_test multiplex-1.9.3  { multiplex_set db main 32768 16 }        {SQLITE_OK}
do_test multiplex-1.9.4  { multiplex_set db main 32768 -1 }        {SQLITE_MISUSE}
do_test multiplex-1.9.5  { multiplex_set db main -1 16 }           {SQLITE_MISUSE}
do_test multiplex-1.9.6  { multiplex_set db main 31 16 }           {SQLITE_OK}
do_test multiplex-1.9.7  { multiplex_set db main 32768 100 }       {SQLITE_MISUSE}
do_test multiplex-1.9.8  { multiplex_set db main 1073741824 1 }    {SQLITE_OK}
do_test multiplex-1.9.9  { db close }                              {}
do_test multiplex-1.9.10 { sqlite3_multiplex_shutdown }            {SQLITE_OK}

do_test multiplex-1.10.1  { sqlite3_multiplex_initialize "" 1 }                     {SQLITE_OK}
do_test multiplex-1.10.2  { sqlite3 db test.db }                                    {}
do_test multiplex-1.10.3  { execsql { SELECT multiplex_control(2, 32768); } }       {SQLITE_OK}
do_test multiplex-1.10.4  { execsql { SELECT multiplex_control(3, -1); } }          {SQLITE_MISUSE}
do_test multiplex-1.10.5  { execsql { SELECT multiplex_control(2, -1); } }          {SQLITE_MISUSE}
do_test multiplex-1.10.6  { execsql { SELECT multiplex_control(2, 31); } }          {SQLITE_OK}
do_test multiplex-1.10.7  { execsql { SELECT multiplex_control(3, 100); } }         {SQLITE_MISUSE}
do_test multiplex-1.10.8  { execsql { SELECT multiplex_control(2, 1073741824); } }  {SQLITE_OK}
do_test multiplex-1.10.9  { db close }                                              {}
do_test multiplex-1.10.10 { sqlite3_multiplex_shutdown }                            {SQLITE_OK}

do_test multiplex-1.11.1  { sqlite3_multiplex_initialize "" 1 }                 {SQLITE_OK}
do_test multiplex-1.11.2  { sqlite3 db test.db }                                {}
do_test multiplex-1.11.3  { sqlite3_multiplex_control db main enable 0  }       {SQLITE_OK}
do_test multiplex-1.11.4  { sqlite3_multiplex_control db main enable 1  }       {SQLITE_OK}
do_test multiplex-1.11.5  { sqlite3_multiplex_control db main enable -1 }       {SQLITE_OK}
do_test multiplex-1.11.6  { db close }                                          {}
do_test multiplex-1.11.7  { sqlite3_multiplex_shutdown }                        {SQLITE_OK}

do_test multiplex-1.12.1  { sqlite3_multiplex_initialize "" 1 }                 {SQLITE_OK}
do_test multiplex-1.12.2  { sqlite3 db test.db }                                {}
do_test multiplex-1.12.3  { execsql { SELECT multiplex_control(1, 0); } }       {SQLITE_OK}
do_test multiplex-1.12.4  { execsql { SELECT multiplex_control(1, 1); } }       {SQLITE_OK}
do_test multiplex-1.12.5  { execsql { SELECT multiplex_control(1, -1); } }      {SQLITE_OK}
do_test multiplex-1.12.6  { db close }                                          {}
do_test multiplex-1.12.7  { sqlite3_multiplex_shutdown }                        {SQLITE_OK}

#-------------------------------------------------------------------------
# Some simple warm-body tests with a single database file in rollback 
# mode:
#
#   multiplex-2.1.*: Test simple writing to a multiplex file.
#
#   multiplex-2.2.*: More writing.
#
#   multiplex-2.3.*: Open and close a second db.
#
#   multiplex-2.4.*: Try to shutdown the multiplex system before closing the db
#                file. Check that this fails and the multiplex system still works
#                afterwards. Then close the database and successfully shut
#                down the multiplex system.
#
#   multiplex-2.5.*: More reading/writing.
#
#   multiplex-2.6.*: More reading/writing with varying small chunk sizes, as
#                well as varying journal mode.
#
#   multiplex-2.7.*: Disable/enable tests.
#

sqlite3_multiplex_initialize "" 1
multiplex_set db main 32768 16

do_test multiplex-2.1.2 {
  sqlite3 db test.db
  execsql {

    do_test multiplex-2.6.99.$sz.$jmode {
      db close
      sqlite3_multiplex_shutdown
    } {SQLITE_OK}

  }
}

do_test multiplex-2.7.1  { multiplex_delete test.db }                          {}
do_test multiplex-2.7.2  { sqlite3_multiplex_initialize "" 1 }                 {SQLITE_OK}
do_test multiplex-2.7.3  { sqlite3 db test.db }                                {}
do_test multiplex-2.7.4  { execsql { SELECT multiplex_control(2, 65536); } }   {SQLITE_OK}
do_test multiplex-2.7.5  { execsql { SELECT multiplex_control(1, 0); } }       {SQLITE_OK}
do_test multiplex-2.7.6 { 
  execsql { 
    CREATE TABLE t1(a PRIMARY KEY, b);
    INSERT INTO t1 VALUES(1, randomblob(1000));
  }
} {}
# verify only one file, and file size is less than chunks size
do_test multiplex-2.7.7  { expr ([file size [multiplex_name test.db 0]] < 65536) } {1}
do_test multiplex-2.7.8  { file exists [multiplex_name test.db 1] }                {0}
do_test multiplex-2.7.9 { 
  execsql { 
    INSERT INTO t1 VALUES(1, randomblob(65536));
  }
} {}
# verify only one file, and file size exceeds chunks size
do_test multiplex-2.7.10 { expr ([file size [multiplex_name test.db 0]] > 65536) } {1}
do_test multiplex-2.7.11 { file exists [multiplex_name test.db 1] }                {0}
do_test multiplex-2.7.12 { db close }                                              {}
do_test multiplex-2.7.13 { sqlite3_multiplex_shutdown }                            {SQLITE_OK}


#-------------------------------------------------------------------------
# Try some tests with more than one connection to a database file. Still
# in rollback mode.
#
#   multiplex-3.1.*: Two connections to a single database file.
#