/*
** If pFile is currently larger than iSize bytes, then truncate it to
** exactly iSize bytes. If pFile is not larger than iSize bytes, then
** this function is a no-op.
**
** Return SQLITE_OK if everything is successful, or an SQLite error
** code if an error occurs.
*/
static int backupTruncateFile(sqlite3_file *pFile, i64 iSize){
i64 iCurrent;
int rc = sqlite3OsFileSize(pFile, &iCurrent);
if( rc==SQLITE_OK && iCurrent>iSize ){
rc = sqlite3OsTruncate(pFile, iSize);
}
return rc;
}
/*
** Truncate the file.
*/
static int jrnlTruncate(sqlite3_file *pJfd, sqlite_int64 size){
int rc = SQLITE_OK;
JournalFile *p = (JournalFile *)pJfd;
if( p->pReal ){
rc = sqlite3OsTruncate(p->pReal, size);
}else if( size<p->iSize ){
p->iSize = size;
}
return rc;
}
/*
** Truncate an jt-file.
*/
static int jtTruncate(sqlite3_file *pFile, sqlite_int64 size){
jt_file *p = (jt_file *)pFile;
if( p->flags&SQLITE_OPEN_MAIN_JOURNAL && size==0 ){
/* Truncating a journal file. This is the end of a transaction. */
jt_file *pMain = locateDatabaseHandle(p->zName);
closeTransaction(pMain);
}
if( p->flags&SQLITE_OPEN_MAIN_DB && p->pWritable ){
u32 pgno;
u32 locking_page = (u32)(PENDING_BYTE/p->nPagesize+1);
for(pgno=size/p->nPagesize+1; pgno<=p->nPage; pgno++){
assert( pgno==locking_page || sqlite3BitvecTest(p->pWritable, pgno) );
}
}
return sqlite3OsTruncate(p->pReal, size);
}
/*
** Truncate an tvfs-file.
*/
static int tvfsTruncate(sqlite3_file *pFile, sqlite_int64 size){
int rc = SQLITE_OK;
TestvfsFd *pFd = tvfsGetFd(pFile);
Testvfs *p = (Testvfs *)pFd->pVfs->pAppData;
if( p->pScript && p->mask&TESTVFS_TRUNCATE_MASK ){
tvfsExecTcl(p, "xTruncate",
Tcl_NewStringObj(pFd->zFilename, -1), pFd->pShmId, 0, 0
);
tvfsResultCode(p, &rc);
}
if( rc==SQLITE_OK ){
rc = sqlite3OsTruncate(pFd->pReal, size);
}
return rc;
}
/*
** Flush the write-list as if xSync() had been called on file handle
** pFile. If isCrash is true, simulate a crash.
*/
static int writeListSync(CrashFile *pFile, int isCrash){
int rc = SQLITE_OK;
int iDc = g.iDeviceCharacteristics;
WriteBuffer *pWrite;
WriteBuffer **ppPtr;
/* If this is not a crash simulation, set pFinal to point to the
** last element of the write-list that is associated with file handle
** pFile.
**
** If this is a crash simulation, set pFinal to an arbitrarily selected
** element of the write-list.
*/
WriteBuffer *pFinal = 0;
if( !isCrash ){
for(pWrite=g.pWriteList; pWrite; pWrite=pWrite->pNext){
if( pWrite->pFile==pFile ){
pFinal = pWrite;
}
}
}else if( iDc&(SQLITE_IOCAP_SEQUENTIAL|SQLITE_IOCAP_SAFE_APPEND) ){
int nWrite = 0;
int iFinal;
for(pWrite=g.pWriteList; pWrite; pWrite=pWrite->pNext) nWrite++;
sqlite3Randomness(sizeof(int), &iFinal);
iFinal = ((iFinal<0)?-1*iFinal:iFinal)%nWrite;
for(pWrite=g.pWriteList; iFinal>0; pWrite=pWrite->pNext) iFinal--;
pFinal = pWrite;
}
#ifdef TRACE_CRASHTEST
printf("Sync %s (is %s crash)\n", pFile->zName, (isCrash?"a":"not a"));
#endif
ppPtr = &g.pWriteList;
for(pWrite=*ppPtr; rc==SQLITE_OK && pWrite; pWrite=*ppPtr){
sqlite3_file *pRealFile = pWrite->pFile->pRealFile;
/* (eAction==1) -> write block out normally,
** (eAction==2) -> do nothing,
** (eAction==3) -> trash sectors.
*/
int eAction = 0;
if( !isCrash ){
eAction = 2;
if( (pWrite->pFile==pFile || iDc&SQLITE_IOCAP_SEQUENTIAL) ){
eAction = 1;
}
}else{
char random;
sqlite3Randomness(1, &random);
/* Do not select option 3 (sector trashing) if the IOCAP_ATOMIC flag
** is set or this is an OsTruncate(), not an Oswrite().
*/
if( (iDc&SQLITE_IOCAP_ATOMIC) || (pWrite->zBuf==0) ){
random &= 0x01;
}
/* If IOCAP_SEQUENTIAL is set and this is not the final entry
** in the truncated write-list, always select option 1 (write
** out correctly).
*/
if( (iDc&SQLITE_IOCAP_SEQUENTIAL && pWrite!=pFinal) ){
random = 0;
}
/* If IOCAP_SAFE_APPEND is set and this OsWrite() operation is
** an append (first byte of the written region is 1 byte past the
** current EOF), always select option 1 (write out correctly).
*/
if( iDc&SQLITE_IOCAP_SAFE_APPEND && pWrite->zBuf ){
i64 iSize;
sqlite3OsFileSize(pRealFile, &iSize);
if( iSize==pWrite->iOffset ){
random = 0;
}
}
if( (random&0x06)==0x06 ){
eAction = 3;
}else{
eAction = ((random&0x01)?2:1);
}
}
switch( eAction ){
case 1: { /* Write out correctly */
if( pWrite->zBuf ){
rc = sqlite3OsWrite(
pRealFile, pWrite->zBuf, pWrite->nBuf, pWrite->iOffset
);
}else{
rc = sqlite3OsTruncate(pRealFile, pWrite->iOffset);
}
*ppPtr = pWrite->pNext;
#ifdef TRACE_CRASHTEST
if( isCrash ){
printf("Writing %d bytes @ %d (%s)\n",
pWrite->nBuf, (int)pWrite->iOffset, pWrite->pFile->zName
);
}
#endif
sqlite3_free(pWrite);
break;
}
case 2: { /* Do nothing */
ppPtr = &pWrite->pNext;
#ifdef TRACE_CRASHTEST
if( isCrash ){
printf("Omiting %d bytes @ %d (%s)\n",
pWrite->nBuf, (int)pWrite->iOffset, pWrite->pFile->zName
);
}
#endif
break;
}
case 3: { /* Trash sectors */
u8 *zGarbage;
int iFirst = (pWrite->iOffset/g.iSectorSize);
int iLast = (pWrite->iOffset+pWrite->nBuf-1)/g.iSectorSize;
assert(pWrite->zBuf);
#ifdef TRACE_CRASHTEST
printf("Trashing %d sectors @ sector %d (%s)\n",
1+iLast-iFirst, iFirst, pWrite->pFile->zName
);
#endif
zGarbage = sqlite3_malloc(g.iSectorSize);
if( zGarbage ){
sqlite3_int64 i;
for(i=iFirst; rc==SQLITE_OK && i<=iLast; i++){
sqlite3Randomness(g.iSectorSize, zGarbage);
rc = sqlite3OsWrite(
pRealFile, zGarbage, g.iSectorSize, i*g.iSectorSize
);
}
sqlite3_free(zGarbage);
}else{
rc = SQLITE_NOMEM;
}
ppPtr = &pWrite->pNext;
break;
}
default:
assert(!"Cannot happen");
}
if( pWrite==pFinal ) break;
}
if( rc==SQLITE_OK && isCrash ){
exit(-1);
}
for(pWrite=g.pWriteList; pWrite && pWrite->pNext; pWrite=pWrite->pNext);
g.pWriteListEnd = pWrite;
return rc;
}
/*
** Truncate an devsym-file.
*/
static int devsymTruncate(sqlite3_file *pFile, sqlite_int64 size){
devsym_file *p = (devsym_file *)pFile;
return sqlite3OsTruncate(p->pReal, size);
}
//Read/Write/Seek/Truncate test
void Test2()
{
sqlite3_vfs* vfs = sqlite3_vfs_find(KSymbianVfsNameZ);
TEST(vfs != NULL);
sqlite3_file* osFile = (sqlite3_file*)User::Alloc(vfs->szOsFile);
TEST(osFile != NULL);
//Creating a new file
int err = sqlite3OsDelete(vfs, KTestFile1Z, 0);
TEST2(err, SQLITE_OK);
int res = 0;
err = sqlite3OsAccess(vfs, KTestFile1Z, SQLITE_ACCESS_EXISTS, &res);
TEST2(err, SQLITE_OK);
TEST2(res, 0);
err = sqlite3OsOpen(vfs, KTestFile1Z, osFile, SQLITE_OPEN_READWRITE | SQLITE_OPEN_CREATE, 0);
TEST2(err, SQLITE_OK);
//Writing at the beginning of the file
err = sqlite3OsWrite(osFile, "123456", 6, 0);
TEST2(err, SQLITE_OK);
//Verify the written data
char data[20];
err = sqlite3OsRead(osFile, data, 6, 0);
TEST2(err, SQLITE_OK);
err = memcmp(data, "123456", 6);
TEST2(err, 0);
//Writing at beyond the end of the file
err = sqlite3OsWrite(osFile, "abcdefgh", 8, 100);
TEST2(err, SQLITE_OK);
//Verify the written data
err = sqlite3OsRead(osFile, data, 8, 100);
TEST2(err, SQLITE_OK);
err = memcmp(data, "abcdefgh", 8);
TEST2(err, 0);
//Truncate the file
err = sqlite3OsTruncate(osFile, 3);
TEST2(err, SQLITE_OK);
//Write more data
err = sqlite3OsWrite(osFile, "xyz", 3, 3);
TEST2(err, SQLITE_OK);
//Verify the written data
err = sqlite3OsRead(osFile, data, 6, 0);
TEST2(err, SQLITE_OK);
err = memcmp(data, "123xyz", 6);
TEST2(err, 0);
//Check the file size
TInt64 fileSize = 0;
err = sqlite3OsFileSize(osFile, &fileSize);
TEST2(err, SQLITE_OK);
TEST(fileSize == 6);
//FileControl - lock type
int lockType = -1;
err = osFile->pMethods->xFileControl(osFile, SQLITE_FCNTL_LOCKSTATE, &lockType);
TEST2(err, SQLITE_OK);
TEST2(lockType, NO_LOCK);
//FileControl - set callback - NULL callback
err = osFile->pMethods->xFileControl(osFile, KSqlFcntlRegisterFreePageCallback, 0);
TEST2(err, SQLITE_ERROR);
//FileControl - set callback - invalid callback object
TSqlFreePageCallback cbck;
err = osFile->pMethods->xFileControl(osFile, KSqlFcntlRegisterFreePageCallback, &cbck);
TEST2(err, SQLITE_ERROR);
//FileControl - invalid op-code
err = osFile->pMethods->xFileControl(osFile, 90234, 0);
TEST2(err, SQLITE_ERROR);
//Close the file
err = sqlite3OsClose(osFile);
TEST2(err, SQLITE_OK);
//
err = sqlite3OsDelete(vfs, KTestFile1Z, 0);
TEST2(err, SQLITE_OK);
User::Free(osFile);
}
/*
** This procedure runs in a separate thread, reading messages off of the
** write queue and processing them one by one.
**
** If async.writerHaltNow is true, then this procedure exits
** after processing a single message.
**
** If async.writerHaltWhenIdle is true, then this procedure exits when
** the write queue is empty.
**
** If both of the above variables are false, this procedure runs
** indefinately, waiting for operations to be added to the write queue
** and processing them in the order in which they arrive.
**
** An artifical delay of async.ioDelay milliseconds is inserted before
** each write operation in order to simulate the effect of a slow disk.
**
** Only one instance of this procedure may be running at a time.
*/
static void *asyncWriterThread(void *NotUsed){
AsyncWrite *p = 0;
int rc = SQLITE_OK;
int holdingMutex = 0;
if( pthread_mutex_trylock(&async.writerMutex) ){
return 0;
}
while( async.writerHaltNow==0 ){
OsFile *pBase = 0;
if( !holdingMutex ){
pthread_mutex_lock(&async.queueMutex);
}
while( (p = async.pQueueFirst)==0 ){
pthread_cond_broadcast(&async.emptySignal);
if( async.writerHaltWhenIdle ){
pthread_mutex_unlock(&async.queueMutex);
break;
}else{
ASYNC_TRACE(("IDLE\n"));
pthread_cond_wait(&async.queueSignal, &async.queueMutex);
ASYNC_TRACE(("WAKEUP\n"));
}
}
if( p==0 ) break;
holdingMutex = 1;
/* Right now this thread is holding the mutex on the write-op queue.
** Variable 'p' points to the first entry in the write-op queue. In
** the general case, we hold on to the mutex for the entire body of
** the loop.
**
** However in the cases enumerated below, we relinquish the mutex,
** perform the IO, and then re-request the mutex before removing 'p' from
** the head of the write-op queue. The idea is to increase concurrency with
** sqlite threads.
**
** * An ASYNC_CLOSE operation.
** * An ASYNC_OPENEXCLUSIVE operation. For this one, we relinquish
** the mutex, call the underlying xOpenExclusive() function, then
** re-aquire the mutex before seting the AsyncFile.pBaseRead
** variable.
** * ASYNC_SYNC and ASYNC_WRITE operations, if
** SQLITE_ASYNC_TWO_FILEHANDLES was set at compile time and two
** file-handles are open for the particular file being "synced".
*/
if( async.ioError!=SQLITE_OK && p->op!=ASYNC_CLOSE ){
p->op = ASYNC_NOOP;
}
if( p->pFile ){
pBase = p->pFile->pBaseWrite;
if(
p->op==ASYNC_CLOSE ||
p->op==ASYNC_OPENEXCLUSIVE ||
(pBase && (p->op==ASYNC_SYNC || p->op==ASYNC_WRITE) )
){
pthread_mutex_unlock(&async.queueMutex);
holdingMutex = 0;
}
if( !pBase ){
pBase = p->pFile->pBaseRead;
}
}
switch( p->op ){
case ASYNC_NOOP:
break;
case ASYNC_WRITE:
assert( pBase );
ASYNC_TRACE(("WRITE %s %d bytes at %d\n",
p->pFile->zName, p->nByte, p->iOffset));
rc = sqlite3OsSeek(pBase, p->iOffset);
if( rc==SQLITE_OK ){
rc = sqlite3OsWrite(pBase, (const void *)(p->zBuf), p->nByte);
}
break;
case ASYNC_SYNC:
assert( pBase );
ASYNC_TRACE(("SYNC %s\n", p->pFile->zName));
rc = sqlite3OsSync(pBase, p->nByte);
break;
case ASYNC_TRUNCATE:
assert( pBase );
ASYNC_TRACE(("TRUNCATE %s to %d bytes\n", p->pFile->zName, p->iOffset));
rc = sqlite3OsTruncate(pBase, p->iOffset);
break;
case ASYNC_CLOSE:
ASYNC_TRACE(("CLOSE %s\n", p->pFile->zName));
sqlite3OsClose(&p->pFile->pBaseWrite);
sqlite3OsClose(&p->pFile->pBaseRead);
sqlite3OsFree(p->pFile);
break;
case ASYNC_OPENDIRECTORY:
assert( pBase );
ASYNC_TRACE(("OPENDIR %s\n", p->zBuf));
sqlite3OsOpenDirectory(pBase, p->zBuf);
break;
case ASYNC_SETFULLSYNC:
assert( pBase );
ASYNC_TRACE(("SETFULLSYNC %s %d\n", p->pFile->zName, p->nByte));
sqlite3OsSetFullSync(pBase, p->nByte);
break;
case ASYNC_DELETE:
ASYNC_TRACE(("DELETE %s\n", p->zBuf));
rc = xOrigDelete(p->zBuf);
break;
case ASYNC_SYNCDIRECTORY:
ASYNC_TRACE(("SYNCDIR %s\n", p->zBuf));
rc = xOrigSyncDirectory(p->zBuf);
break;
case ASYNC_OPENEXCLUSIVE: {
AsyncFile *pFile = p->pFile;
int delFlag = ((p->iOffset)?1:0);
OsFile *pBase = 0;
ASYNC_TRACE(("OPEN %s delFlag=%d\n", p->zBuf, delFlag));
assert(pFile->pBaseRead==0 && pFile->pBaseWrite==0);
rc = xOrigOpenExclusive(p->zBuf, &pBase, delFlag);
assert( holdingMutex==0 );
pthread_mutex_lock(&async.queueMutex);
holdingMutex = 1;
if( rc==SQLITE_OK ){
pFile->pBaseRead = pBase;
}
break;
}
default: assert(!"Illegal value for AsyncWrite.op");
}
/* If we didn't hang on to the mutex during the IO op, obtain it now
** so that the AsyncWrite structure can be safely removed from the
** global write-op queue.
*/
if( !holdingMutex ){
pthread_mutex_lock(&async.queueMutex);
holdingMutex = 1;
}
/* ASYNC_TRACE(("UNLINK %p\n", p)); */
if( p==async.pQueueLast ){
async.pQueueLast = 0;
}
async.pQueueFirst = p->pNext;
sqlite3OsFree(p);
assert( holdingMutex );
/* An IO error has occured. We cannot report the error back to the
** connection that requested the I/O since the error happened
** asynchronously. The connection has already moved on. There
** really is nobody to report the error to.
**
** The file for which the error occured may have been a database or
** journal file. Regardless, none of the currently queued operations
** associated with the same database should now be performed. Nor should
** any subsequently requested IO on either a database or journal file
** handle for the same database be accepted until the main database
** file handle has been closed and reopened.
**
** Furthermore, no further IO should be queued or performed on any file
** handle associated with a database that may have been part of a
** multi-file transaction that included the database associated with
** the IO error (i.e. a database ATTACHed to the same handle at some
** point in time).
*/
if( rc!=SQLITE_OK ){
async.ioError = rc;
}
/* Drop the queue mutex before continuing to the next write operation
** in order to give other threads a chance to work with the write queue.
*/
if( !async.pQueueFirst || !async.ioError ){
sqlite3ApiExit(0, 0);
pthread_mutex_unlock(&async.queueMutex);
holdingMutex = 0;
if( async.ioDelay>0 ){
sqlite3OsSleep(async.ioDelay);
}else{
sched_yield();
}
}
}
pthread_mutex_unlock(&async.writerMutex);
return 0;
}
