/*
** Usage: fake_big_file N FILENAME
**
** Write a few bytes at the N megabyte point of FILENAME. This will
** create a large file. If the file was a valid SQLite database, then
** the next time the database is opened, SQLite will begin allocating
** new pages after N. If N is 2096 or bigger, this will test the
** ability of SQLite to write to large files.
*/
static int fake_big_file(
void *NotUsed,
Tcl_Interp *interp, /* The TCL interpreter that invoked this command */
int argc, /* Number of arguments */
const char **argv /* Text of each argument */
){
sqlite3_vfs *pVfs;
sqlite3_file *fd = 0;
int rc;
int n;
i64 offset;
char *zFile;
int nFile;
if( argc!=3 ){
Tcl_AppendResult(interp, "wrong # args: should be \"", argv[0],
" N-MEGABYTES FILE\"", 0);
return TCL_ERROR;
}
if( Tcl_GetInt(interp, argv[1], &n) ) return TCL_ERROR;
/* this does not work with MDB */
return TCL_ERROR;
pVfs = sqlite3_vfs_find(0);
nFile = (int)strlen(argv[2]);
zFile = sqlite3_malloc( nFile+2 );
if( zFile==0 ) return TCL_ERROR;
memcpy(zFile, argv[2], nFile+1);
zFile[nFile+1] = 0;
rc = sqlite3OsOpenMalloc(pVfs, zFile, &fd,
(SQLITE_OPEN_CREATE|SQLITE_OPEN_READWRITE|SQLITE_OPEN_MAIN_DB), 0
);
if( rc ){
Tcl_AppendResult(interp, "open failed: ", sqlite3ErrName(rc), 0);
sqlite3_free(zFile);
return TCL_ERROR;
}
offset = n;
offset *= 1024*1024;
rc = sqlite3OsWrite(fd, "Hello, World!", 14, offset);
sqlite3OsCloseFree(fd);
sqlite3_free(zFile);
if( rc ){
Tcl_AppendResult(interp, "write failed: ", sqlite3ErrName(rc), 0);
return TCL_ERROR;
}
return TCL_OK;
}
/*
** Free any cursor components allocated by sqlite3VdbeSorterXXX routines.
*/
void sqlite3VdbeSorterClose(sqlite3 *db, VdbeCursor *pCsr){
VdbeSorter *pSorter = pCsr->pSorter;
if( pSorter ){
if( pSorter->aIter ){
int i;
for(i=0; i<pSorter->nTree; i++){
vdbeSorterIterZero(db, &pSorter->aIter[i]);
}
sqlite3DbFree(db, pSorter->aIter);
}
if( pSorter->pTemp1 ){
sqlite3OsCloseFree(pSorter->pTemp1);
}
vdbeSorterRecordFree(db, pSorter->pRecord);
sqlite3DbFree(db, pSorter->pUnpacked);
sqlite3DbFree(db, pSorter);
pCsr->pSorter = 0;
}
}
/*
** Usage: fake_big_file N FILENAME
**
** Write a few bytes at the N megabyte point of FILENAME. This will
** create a large file. If the file was a valid SQLite database, then
** the next time the database is opened, SQLite will begin allocating
** new pages after N. If N is 2096 or bigger, this will test the
** ability of SQLite to write to large files.
*/
static int fake_big_file(
void *NotUsed,
Tcl_Interp *interp, /* The TCL interpreter that invoked this command */
int argc, /* Number of arguments */
const char **argv /* Text of each argument */
){
sqlite3_vfs *pVfs;
sqlite3_file *fd = 0;
int rc;
int n;
i64 offset;
if( argc!=3 ){
Tcl_AppendResult(interp, "wrong # args: should be \"", argv[0],
" N-MEGABYTES FILE\"", 0);
return TCL_ERROR;
}
if( Tcl_GetInt(interp, argv[1], &n) ) return TCL_ERROR;
/*
* This does not work with Berkeley DB. Making a large file does not cause
* DB to skip the existing pages.
*/
return TCL_ERROR;
pVfs = sqlite3_vfs_find(0);
rc = sqlite3OsOpenMalloc(pVfs, argv[2], &fd,
(SQLITE_OPEN_CREATE|SQLITE_OPEN_READWRITE|SQLITE_OPEN_MAIN_DB), 0
);
if( rc ){
Tcl_AppendResult(interp, "open failed: ", errorName(rc), 0);
return TCL_ERROR;
}
offset = n;
offset *= 1024*1024;
rc = sqlite3OsWrite(fd, "Hello, World!", 14, offset);
sqlite3OsCloseFree(fd);
if( rc ){
Tcl_AppendResult(interp, "write failed: ", errorName(rc), 0);
return TCL_ERROR;
}
return TCL_OK;
}
static int fake_big_file(
void *NotUsed,
Tcl_Interp *interp,
int argc,
const char **argv
){
sqlite3_vfs *pVfs;
sqlite3_file *fd = 0;
int rc;
int n;
i64 offset;
if( argc!=3 ){
Tcl_AppendResult(interp, "wrong # args: should be \"", argv[0],
" N-MEGABYTES FILE\"", 0);
return TCL_ERROR;
}
if( Tcl_GetInt(interp, argv[1], &n) ) return TCL_ERROR;
pVfs = sqlite3_vfs_find(0);
rc = sqlite3OsOpenMalloc(pVfs, argv[2], &fd,
(SQLITE_OPEN_CREATE|SQLITE_OPEN_READWRITE|SQLITE_OPEN_MAIN_DB), 0
);
if( rc ){
Tcl_AppendResult(interp, "open failed: ", errorName(rc), 0);
return TCL_ERROR;
}
offset = n;
offset *= 1024*1024;
rc = sqlite3OsWrite(fd, "Hello, World!", 14, offset);
sqlite3OsCloseFree(fd);
if( rc ){
Tcl_AppendResult(interp, "write failed: ", errorName(rc), 0);
return TCL_ERROR;
}
return TCL_OK;
}
/*
** Once the sorter has been populated, this function is called to prepare
** for iterating through its contents in sorted order.
*/
int sqlite3VdbeSorterRewind(sqlite3 *db, VdbeCursor *pCsr, int *pbEof){
VdbeSorter *pSorter = pCsr->pSorter;
int rc; /* Return code */
sqlite3_file *pTemp2 = 0; /* Second temp file to use */
i64 iWrite2 = 0; /* Write offset for pTemp2 */
int nIter; /* Number of iterators used */
int nByte; /* Bytes of space required for aIter/aTree */
int N = 2; /* Power of 2 >= nIter */
assert( pSorter );
/* If no data has been written to disk, then do not do so now. Instead,
** sort the VdbeSorter.pRecord list. The vdbe layer will read data directly
** from the in-memory list. */
if( pSorter->nPMA==0 ){
*pbEof = !pSorter->pRecord;
assert( pSorter->aTree==0 );
return vdbeSorterSort(pCsr);
}
/* Write the current b-tree to a PMA. Close the b-tree cursor. */
rc = vdbeSorterListToPMA(db, pCsr);
if( rc!=SQLITE_OK ) return rc;
/* Allocate space for aIter[] and aTree[]. */
nIter = pSorter->nPMA;
if( nIter>SORTER_MAX_MERGE_COUNT ) nIter = SORTER_MAX_MERGE_COUNT;
assert( nIter>0 );
while( N<nIter ) N += N;
nByte = N * (sizeof(int) + sizeof(VdbeSorterIter));
pSorter->aIter = (VdbeSorterIter *)sqlite3DbMallocZero(db, nByte);
if( !pSorter->aIter ) return SQLITE_NOMEM;
pSorter->aTree = (int *)&pSorter->aIter[N];
pSorter->nTree = N;
do {
int iNew; /* Index of new, merged, PMA */
for(iNew=0;
rc==SQLITE_OK && iNew*SORTER_MAX_MERGE_COUNT<pSorter->nPMA;
iNew++
){
i64 nWrite; /* Number of bytes in new PMA */
/* If there are SORTER_MAX_MERGE_COUNT or less PMAs in file pTemp1,
** initialize an iterator for each of them and break out of the loop.
** These iterators will be incrementally merged as the VDBE layer calls
** sqlite3VdbeSorterNext().
**
** Otherwise, if pTemp1 contains more than SORTER_MAX_MERGE_COUNT PMAs,
** initialize interators for SORTER_MAX_MERGE_COUNT of them. These PMAs
** are merged into a single PMA that is written to file pTemp2.
*/
rc = vdbeSorterInitMerge(db, pCsr, &nWrite);
assert( rc!=SQLITE_OK || pSorter->aIter[ pSorter->aTree[1] ].pFile );
if( rc!=SQLITE_OK || pSorter->nPMA<=SORTER_MAX_MERGE_COUNT ){
break;
}
/* Open the second temp file, if it is not already open. */
if( pTemp2==0 ){
assert( iWrite2==0 );
rc = vdbeSorterOpenTempFile(db, &pTemp2);
}
if( rc==SQLITE_OK ){
rc = vdbeSorterWriteVarint(pTemp2, nWrite, &iWrite2);
}
if( rc==SQLITE_OK ){
int bEof = 0;
while( rc==SQLITE_OK && bEof==0 ){
int nToWrite;
VdbeSorterIter *pIter = &pSorter->aIter[ pSorter->aTree[1] ];
assert( pIter->pFile );
nToWrite = pIter->nKey + sqlite3VarintLen(pIter->nKey);
rc = sqlite3OsWrite(pTemp2, pIter->aAlloc, nToWrite, iWrite2);
iWrite2 += nToWrite;
if( rc==SQLITE_OK ){
rc = sqlite3VdbeSorterNext(db, pCsr, &bEof);
}
}
}
}
if( pSorter->nPMA<=SORTER_MAX_MERGE_COUNT ){
break;
}else{
sqlite3_file *pTmp = pSorter->pTemp1;
pSorter->nPMA = iNew;
pSorter->pTemp1 = pTemp2;
pTemp2 = pTmp;
pSorter->iWriteOff = iWrite2;
pSorter->iReadOff = 0;
iWrite2 = 0;
}
}while( rc==SQLITE_OK );
if( pTemp2 ){
sqlite3OsCloseFree(pTemp2);
}
*pbEof = (pSorter->aIter[pSorter->aTree[1]].pFile==0);
return rc;
}
