/*
* GetTransactionSnapshot
* Get the appropriate snapshot for a new query in a transaction.
*
* Note that the return value may point at static storage that will be modified
* by future calls and by CommandCounterIncrement(). Callers should call
* RegisterSnapshot or PushActiveSnapshot on the returned snap if it is to be
* used very long.
*/
Snapshot
GetTransactionSnapshot(void)
{
/* First call in transaction? */
if (!FirstSnapshotSet)
{
Assert(RegisteredSnapshots == 0);
CurrentSnapshot = GetSnapshotData(&CurrentSnapshotData);
FirstSnapshotSet = true;
/*
* In serializable mode, the first snapshot must live until end of
* xact regardless of what the caller does with it, so we must
* register it internally here and unregister it at end of xact.
*/
if (IsXactIsoLevelSerializable)
{
CurrentSnapshot = RegisterSnapshotOnOwner(CurrentSnapshot,
TopTransactionResourceOwner);
registered_serializable = true;
}
return CurrentSnapshot;
}
if (IsXactIsoLevelSerializable)
return CurrentSnapshot;
CurrentSnapshot = GetSnapshotData(&CurrentSnapshotData);
return CurrentSnapshot;
}
/*
* CopyCurrentSnapshot
* Make a snapshot that is up-to-date as of the current instant,
* and return a copy.
*
* The copy is palloc'd in the current memory context.
*/
Snapshot
CopyCurrentSnapshot(void)
{
Snapshot currentSnapshot;
Snapshot snapshot;
if (QuerySnapshot == NULL) /* should not be first call in xact */
elog(ERROR, "no snapshot has been set");
/* Update the static struct */
currentSnapshot = GetSnapshotData(&CurrentSnapshotData, false);
currentSnapshot->curcid = GetCurrentCommandId();
/* Make a copy */
snapshot = (Snapshot) palloc(sizeof(SnapshotData));
memcpy(snapshot, currentSnapshot, sizeof(SnapshotData));
if (snapshot->xcnt > 0)
{
snapshot->xip = (TransactionId *)
palloc(snapshot->xcnt * sizeof(TransactionId));
memcpy(snapshot->xip, currentSnapshot->xip,
snapshot->xcnt * sizeof(TransactionId));
}
else
snapshot->xip = NULL;
return snapshot;
}
/*
* GetNonHistoricCatalogSnapshot
* Get a snapshot that is sufficiently up-to-date for scan of the system
* catalog with the specified OID, even while historic snapshots are set
* up.
*/
Snapshot
GetNonHistoricCatalogSnapshot(Oid relid)
{
/*
* If the caller is trying to scan a relation that has no syscache, no
* catcache invalidations will be sent when it is updated. For a few key
* relations, snapshot invalidations are sent instead. If we're trying to
* scan a relation for which neither catcache nor snapshot invalidations
* are sent, we must refresh the snapshot every time.
*/
if (!CatalogSnapshotStale && !RelationInvalidatesSnapshotsOnly(relid) &&
!RelationHasSysCache(relid))
CatalogSnapshotStale = true;
if (CatalogSnapshotStale)
{
/* Get new snapshot. */
CatalogSnapshot = GetSnapshotData(&CatalogSnapshotData);
/*
* Mark new snapshost as valid. We must do this last, in case an
* ERROR occurs inside GetSnapshotData().
*/
CatalogSnapshotStale = false;
}
return CatalogSnapshot;
}
/*
* GetLatestSnapshot
* Get a snapshot that is up-to-date as of the current instant,
* even if we are executing in transaction-snapshot mode.
*/
Snapshot
GetLatestSnapshot(void)
{
/*
* We might be able to relax this, but nothing that could otherwise work
* needs it.
*/
if (IsInParallelMode())
elog(ERROR,
"cannot update SecondarySnapshot during a parallel operation");
/*
* So far there are no cases requiring support for GetLatestSnapshot()
* during logical decoding, but it wouldn't be hard to add if required.
*/
Assert(!HistoricSnapshotActive());
/* If first call in transaction, go ahead and set the xact snapshot */
if (!FirstSnapshotSet)
return GetTransactionSnapshot();
SecondarySnapshot = GetSnapshotData(&SecondarySnapshotData);
return SecondarySnapshot;
}
/*
* GetTransactionSnapshot
* Get the appropriate snapshot for a new query in a transaction.
*
* The SerializableSnapshot is the first one taken in a transaction.
* In serializable mode we just use that one throughout the transaction.
* In read-committed mode, we take a new snapshot each time we are called.
*
* Note that the return value points at static storage that will be modified
* by future calls and by CommandCounterIncrement(). Callers should copy
* the result with CopySnapshot() if it is to be used very long.
*/
Snapshot
GetTransactionSnapshot(void)
{
/* First call in transaction? */
if (SerializableSnapshot == NULL)
{
SerializableSnapshot = GetSnapshotData(&SerializableSnapshotData, true);
return SerializableSnapshot;
}
if (IsXactIsoLevelSerializable)
return SerializableSnapshot;
LatestSnapshot = GetSnapshotData(&LatestSnapshotData, false);
return LatestSnapshot;
}
/*
* GetTransactionSnapshot
* Get the appropriate snapshot for a new query in a transaction.
*
* Note that the return value may point at static storage that will be modified
* by future calls and by CommandCounterIncrement(). Callers should call
* RegisterSnapshot or PushActiveSnapshot on the returned snap if it is to be
* used very long.
*/
Snapshot
GetTransactionSnapshot(void)
{
/* First call in transaction? */
if (!FirstSnapshotSet)
{
Assert(RegisteredSnapshots == 0);
Assert(FirstXactSnapshot == NULL);
/*
* In transaction-snapshot mode, the first snapshot must live until
* end of xact regardless of what the caller does with it, so we must
* make a copy of it rather than returning CurrentSnapshotData
* directly. Furthermore, if we're running in serializable mode,
* predicate.c needs to wrap the snapshot fetch in its own processing.
*/
if (IsolationUsesXactSnapshot())
{
/* First, create the snapshot in CurrentSnapshotData */
if (IsolationIsSerializable())
CurrentSnapshot = GetSerializableTransactionSnapshot(&CurrentSnapshotData);
else
CurrentSnapshot = GetSnapshotData(&CurrentSnapshotData);
/* Make a saved copy */
CurrentSnapshot = CopySnapshot(CurrentSnapshot);
FirstXactSnapshot = CurrentSnapshot;
/* Mark it as "registered" in FirstXactSnapshot */
FirstXactSnapshot->regd_count++;
RegisteredSnapshots++;
}
else
CurrentSnapshot = GetSnapshotData(&CurrentSnapshotData);
FirstSnapshotSet = true;
return CurrentSnapshot;
}
if (IsolationUsesXactSnapshot())
return CurrentSnapshot;
CurrentSnapshot = GetSnapshotData(&CurrentSnapshotData);
return CurrentSnapshot;
}
/*
* SetQuerySnapshot
* Initialize query snapshot for a new query
*
* The SerializableSnapshot is the first one taken in a transaction.
* In serializable mode we just use that one throughout the transaction.
* In read-committed mode, we take a new snapshot at the start of each query.
*/
void
SetQuerySnapshot(void)
{
/* 1st call in xaction? */
if (SerializableSnapshot == NULL)
{
SerializableSnapshot = GetSnapshotData(&SerializableSnapshotData, true);
QuerySnapshot = SerializableSnapshot;
Assert(QuerySnapshot != NULL);
return;
}
if (XactIsoLevel == XACT_SERIALIZABLE)
QuerySnapshot = SerializableSnapshot;
else
QuerySnapshot = GetSnapshotData(&QuerySnapshotData, false);
Assert(QuerySnapshot != NULL);
}
/*
* GetLatestSnapshot
* Get a snapshot that is up-to-date as of the current instant,
* even if we are executing in transaction-snapshot mode.
*/
Snapshot
GetLatestSnapshot(void)
{
/* Should not be first call in transaction */
if (!FirstSnapshotSet)
elog(ERROR, "no snapshot has been set");
SecondarySnapshot = GetSnapshotData(&SecondarySnapshotData);
return SecondarySnapshot;
}
/*
* GetLatestSnapshot
* Get a snapshot that is up-to-date as of the current instant,
* even if we are executing in SERIALIZABLE mode.
*/
Snapshot
GetLatestSnapshot(void)
{
/* Should not be first call in transaction */
if (SerializableSnapshot == NULL)
elog(ERROR, "no snapshot has been set");
LatestSnapshot = GetSnapshotData(&LatestSnapshotData, false);
return LatestSnapshot;
}
/*
* GetLatestSnapshot
* Get a snapshot that is up-to-date as of the current instant,
* even if we are executing in transaction-snapshot mode.
*/
Snapshot
GetLatestSnapshot(void)
{
/* If first call in transaction, go ahead and set the xact snapshot */
if (!FirstSnapshotSet)
return GetTransactionSnapshot();
SecondarySnapshot = GetSnapshotData(&SecondarySnapshotData);
return SecondarySnapshot;
}
/*
* GetTransactionSnapshot
* Get the appropriate snapshot for a new query in a transaction.
*
* Note that the return value may point at static storage that will be modified
* by future calls and by CommandCounterIncrement(). Callers should call
* RegisterSnapshot or PushActiveSnapshot on the returned snap if it is to be
* used very long.
*/
Snapshot
GetTransactionSnapshot(void)
{
/* First call in transaction? */
if (!FirstSnapshotSet)
{
Assert(RegisteredSnapshots == 0);
/*
* In transaction-snapshot mode, the first snapshot must live until
* end of xact regardless of what the caller does with it, so we must
* register it internally here and unregister it at end of xact.
*/
if (IsolationUsesXactSnapshot())
{
if (IsolationIsSerializable())
CurrentSnapshot = RegisterSerializableTransaction(&CurrentSnapshotData);
else
{
CurrentSnapshot = GetSnapshotData(&CurrentSnapshotData);
CurrentSnapshot = RegisterSnapshotOnOwner(CurrentSnapshot,
TopTransactionResourceOwner);
}
registered_xact_snapshot = true;
}
else
CurrentSnapshot = GetSnapshotData(&CurrentSnapshotData);
FirstSnapshotSet = true;
return CurrentSnapshot;
}
if (IsolationUsesXactSnapshot())
return CurrentSnapshot;
CurrentSnapshot = GetSnapshotData(&CurrentSnapshotData);
return CurrentSnapshot;
}
/*
* GetLatestSnapshot
* Get a snapshot that is up-to-date as of the current instant,
* even if we are executing in transaction-snapshot mode.
*/
Snapshot
GetLatestSnapshot(void)
{
/*
* So far there are no cases requiring support for GetLatestSnapshot()
* during logical decoding, but it wouldn't be hard to add if required.
*/
Assert(!HistoricSnapshotActive());
/* If first call in transaction, go ahead and set the xact snapshot */
if (!FirstSnapshotSet)
return GetTransactionSnapshot();
SecondarySnapshot = GetSnapshotData(&SecondarySnapshotData);
return SecondarySnapshot;
}
/*
* SetTransactionSnapshot
* Set the transaction's snapshot from an imported MVCC snapshot.
*
* Note that this is very closely tied to GetTransactionSnapshot --- it
* must take care of all the same considerations as the first-snapshot case
* in GetTransactionSnapshot.
*/
static void
SetTransactionSnapshot(Snapshot sourcesnap, TransactionId sourcexid)
{
/* Caller should have checked this already */
Assert(!FirstSnapshotSet);
Assert(RegisteredSnapshots == 0);
Assert(FirstXactSnapshot == NULL);
/*
* Even though we are not going to use the snapshot it computes, we must
* call GetSnapshotData, for two reasons: (1) to be sure that
* CurrentSnapshotData's XID arrays have been allocated, and (2) to update
* RecentXmin and RecentGlobalXmin. (We could alternatively include those
* two variables in exported snapshot files, but it seems better to have
* snapshot importers compute reasonably up-to-date values for them.)
*/
CurrentSnapshot = GetSnapshotData(&CurrentSnapshotData);
/*
* Now copy appropriate fields from the source snapshot.
*/
CurrentSnapshot->xmin = sourcesnap->xmin;
CurrentSnapshot->xmax = sourcesnap->xmax;
CurrentSnapshot->xcnt = sourcesnap->xcnt;
Assert(sourcesnap->xcnt <= GetMaxSnapshotXidCount());
memcpy(CurrentSnapshot->xip, sourcesnap->xip,
sourcesnap->xcnt * sizeof(TransactionId));
CurrentSnapshot->subxcnt = sourcesnap->subxcnt;
Assert(sourcesnap->subxcnt <= GetMaxSnapshotSubxidCount());
memcpy(CurrentSnapshot->subxip, sourcesnap->subxip,
sourcesnap->subxcnt * sizeof(TransactionId));
CurrentSnapshot->suboverflowed = sourcesnap->suboverflowed;
CurrentSnapshot->takenDuringRecovery = sourcesnap->takenDuringRecovery;
/* NB: curcid should NOT be copied, it's a local matter */
/*
* Now we have to fix what GetSnapshotData did with MyProc->xmin and
* TransactionXmin. There is a race condition: to make sure we are not
* causing the global xmin to go backwards, we have to test that the
* source transaction is still running, and that has to be done atomically.
* So let procarray.c do it.
*
* Note: in serializable mode, predicate.c will do this a second time.
* It doesn't seem worth contorting the logic here to avoid two calls,
* especially since it's not clear that predicate.c *must* do this.
*/
if (!ProcArrayInstallImportedXmin(CurrentSnapshot->xmin, sourcexid))
ereport(ERROR,
(errcode(ERRCODE_OBJECT_NOT_IN_PREREQUISITE_STATE),
errmsg("could not import the requested snapshot"),
errdetail("The source transaction %u is not running anymore.",
sourcexid)));
/*
* In transaction-snapshot mode, the first snapshot must live until end of
* xact, so we must make a copy of it. Furthermore, if we're running in
* serializable mode, predicate.c needs to do its own processing.
*/
if (IsolationUsesXactSnapshot())
{
if (IsolationIsSerializable())
SetSerializableTransactionSnapshot(CurrentSnapshot, sourcexid);
/* Make a saved copy */
CurrentSnapshot = CopySnapshot(CurrentSnapshot);
FirstXactSnapshot = CurrentSnapshot;
/* Mark it as "registered" in FirstXactSnapshot */
FirstXactSnapshot->regd_count++;
RegisteredSnapshots++;
}
FirstSnapshotSet = true;
}
/*
* GetTransactionSnapshot
* Get the appropriate snapshot for a new query in a transaction.
*
* Note that the return value may point at static storage that will be modified
* by future calls and by CommandCounterIncrement(). Callers should call
* RegisterSnapshot or PushActiveSnapshot on the returned snap if it is to be
* used very long.
*/
Snapshot
GetTransactionSnapshot(void)
{
/*
* Return historic snapshot if doing logical decoding. We'll never need a
* non-historic transaction snapshot in this (sub-)transaction, so there's
* no need to be careful to set one up for later calls to
* GetTransactionSnapshot().
*/
if (HistoricSnapshotActive())
{
Assert(!FirstSnapshotSet);
return HistoricSnapshot;
}
/* First call in transaction? */
if (!FirstSnapshotSet)
{
Assert(pairingheap_is_empty(&RegisteredSnapshots));
Assert(FirstXactSnapshot == NULL);
if (IsInParallelMode())
elog(ERROR,
"cannot take query snapshot during a parallel operation");
/*
* In transaction-snapshot mode, the first snapshot must live until
* end of xact regardless of what the caller does with it, so we must
* make a copy of it rather than returning CurrentSnapshotData
* directly. Furthermore, if we're running in serializable mode,
* predicate.c needs to wrap the snapshot fetch in its own processing.
*/
if (IsolationUsesXactSnapshot())
{
/* First, create the snapshot in CurrentSnapshotData */
if (IsolationIsSerializable())
CurrentSnapshot = GetSerializableTransactionSnapshot(&CurrentSnapshotData);
else
CurrentSnapshot = GetSnapshotData(&CurrentSnapshotData);
/* Make a saved copy */
CurrentSnapshot = CopySnapshot(CurrentSnapshot);
FirstXactSnapshot = CurrentSnapshot;
/* Mark it as "registered" in FirstXactSnapshot */
FirstXactSnapshot->regd_count++;
pairingheap_add(&RegisteredSnapshots, &FirstXactSnapshot->ph_node);
}
else
CurrentSnapshot = GetSnapshotData(&CurrentSnapshotData);
/* Don't allow catalog snapshot to be older than xact snapshot. */
CatalogSnapshotStale = true;
FirstSnapshotSet = true;
return CurrentSnapshot;
}
if (IsolationUsesXactSnapshot())
return CurrentSnapshot;
/* Don't allow catalog snapshot to be older than xact snapshot. */
CatalogSnapshotStale = true;
CurrentSnapshot = GetSnapshotData(&CurrentSnapshotData);
return CurrentSnapshot;
}
/*
* GetTransactionSnapshot
* Get the appropriate snapshot for a new query in a transaction.
*
* Note that the return value may point at static storage that will be modified
* by future calls and by CommandCounterIncrement(). Callers should call
* RegisterSnapshot or PushActiveSnapshot on the returned snap if it is to be
* used very long.
*/
Snapshot
GetTransactionSnapshot(void)
{
/* First call in transaction? */
if (!FirstSnapshotSet)
{
Assert(RegisteredSnapshots == 0);
Assert(FirstXactSnapshot == NULL);
/*
* In transaction-snapshot mode, the first snapshot must live until
* end of xact regardless of what the caller does with it, so we must
* make a copy of it rather than returning CurrentSnapshotData
* directly. Furthermore, if we're running in serializable mode,
* predicate.c needs to wrap the snapshot fetch in its own processing.
*/
if (IsolationUsesXactSnapshot())
{
/* First, create the snapshot in CurrentSnapshotData */
if (IsolationIsSerializable())
CurrentSnapshot = GetSerializableTransactionSnapshot(&CurrentSnapshotData);
else
CurrentSnapshot = GetSnapshotData(&CurrentSnapshotData);
/* Make a saved copy */
CurrentSnapshot = CopySnapshot(CurrentSnapshot);
FirstXactSnapshot = CurrentSnapshot;
/* Mark it as "registered" in FirstXactSnapshot */
FirstXactSnapshot->regd_count++;
RegisteredSnapshots++;
}
else
CurrentSnapshot = GetSnapshotData(&CurrentSnapshotData);
FirstSnapshotSet = true;
return CurrentSnapshot;
}
if (IsolationUsesXactSnapshot())
{
#ifdef PGXC
/*
* Consider this test case taken from portals.sql
*
* CREATE TABLE cursor (a int, b int) distribute by replication;
* INSERT INTO cursor VALUES (10);
* BEGIN;
* SET TRANSACTION ISOLATION LEVEL SERIALIZABLE;
* DECLARE c1 NO SCROLL CURSOR FOR SELECT * FROM cursor FOR UPDATE;
* INSERT INTO cursor VALUES (2);
* FETCH ALL FROM c1;
* would result in
* ERROR: attempted to lock invisible tuple
* because FETCH would be sent as a select to the remote nodes
* with command id 0, whereas the command id would be 2
* in the current snapshot.
* (1 sent by Coordinator due to declare cursor &
* 2 because of the insert inside the transaction)
* The command id should therefore be updated in the
* current snapshot.
*/
if (IsConnFromCoord())
SnapshotSetCommandId(GetCurrentCommandId(false));
#endif
return CurrentSnapshot;
}
CurrentSnapshot = GetSnapshotData(&CurrentSnapshotData);
return CurrentSnapshot;
}
void MainUI::OpenDirs(QStringList dirs){
//Now open the dirs
if(dirs.isEmpty()){ dirs << QDir::homePath(); }
QStringList invalid;
for(int i=0; i<dirs.length(); i++){
if(dirs[i].simplified().isEmpty()){ continue; }
//Open this directory in a viewer
if(dirs[i].endsWith("/")){ dirs[i].chop(1); }
if(!QFile::exists(dirs[i])){ invalid << dirs[i]; continue; }
if(DEBUG){ qDebug() << "Open Directory:" << dirs[i]; }
///Get a new Unique ID
int id = 0;
for(int j=0; j<DWLIST.length(); j++){
if(DWLIST[j]->id().section("-",1,1).toInt() >= id){ id = DWLIST[j]->id().section("-",1,1).toInt()+1; }
}
//Create the new DirWidget
DirWidget *DW = new DirWidget("DW-"+QString::number(id), this);
DW->setSizePolicy(QSizePolicy::Expanding, QSizePolicy::Expanding);
ui->BrowserLayout->addWidget(DW);
DWLIST << DW;
//Connect the signals/slots for it
connect(DW, SIGNAL(OpenDirectories(QStringList)), this, SLOT(OpenDirs(QStringList)) );
connect(DW, SIGNAL(LoadDirectory(QString, QString)), worker, SLOT(GetDirData(QString, QString)) );
connect(DW, SIGNAL(findSnaps(QString, QString)), worker, SLOT(GetSnapshotData(QString, QString)) );
connect(DW, SIGNAL(PlayFiles(LFileInfoList)), this, SLOT(OpenPlayer(LFileInfoList)) );
connect(DW, SIGNAL(ViewFiles(LFileInfoList)), this, SLOT(OpenImages(LFileInfoList)) );
connect(DW, SIGNAL(LaunchTerminal(QString)), this, SLOT(OpenTerminal(QString)) );
connect(DW, SIGNAL(CutFiles(QStringList)), this, SLOT(CutFiles(QStringList)) );
connect(DW, SIGNAL(CopyFiles(QStringList)), this, SLOT(CopyFiles(QStringList)) );
connect(DW, SIGNAL(FavoriteFiles(QStringList)), this, SLOT(FavoriteFiles(QStringList)) );
connect(DW, SIGNAL(RenameFiles(QStringList)), this, SLOT(RenameFiles(QStringList)) );
connect(DW, SIGNAL(RemoveFiles(QStringList)), this, SLOT(RemoveFiles(QStringList)) );
connect(DW, SIGNAL(PasteFiles(QString,QStringList)), this, SLOT(PasteFiles(QString, QStringList)) );
connect(DW, SIGNAL(CloseBrowser(QString)), this, SLOT(CloseBrowser(QString)) );
//Now create the tab for this
if(radio_view_tabs->isChecked()){
int index = tabBar->addTab( LXDG::findIcon("folder-open",""), dirs[i].section("/",-1) );
tabBar->setTabWhatsThis( index, "DW-"+QString::number(id) );
tabBar->setCurrentIndex(index);
}else{
//Just make sure the browser tab is visible
bool found = false;
for(int i=0; i<tabBar->count() && !found; i++){
if(tabBar->tabWhatsThis(i)=="browser"){ tabBar->setCurrentIndex(i); found=true; }
}
if(!found){
//Need to create the generic Browser tab
int index = tabBar->addTab( LXDG::findIcon("folder-open",""), "Browser" );
tabBar->setTabWhatsThis( index, "browser" );
tabBar->setCurrentIndex(index);
}
}
//Initialize the widget with the proper settings
DW->setShowDetails(radio_view_details->isChecked());
DW->setShowSidebar(ui->actionShow_Action_Buttons->isChecked());
QList<DirWidget::DETAILTYPES> details; details <<DirWidget::NAME << DirWidget::SIZE << DirWidget::TYPE << DirWidget::DATEMOD;
DW->setDetails(details); //Which details to show and in which order (L->R)
DW->setShowThumbnails(ui->actionShow_Thumbnails->isChecked());
DW->setThumbnailSize(settings->value("iconsize", 32).toInt());
DW->setDirCompleter(dirCompleter);
DW->setShowCloseButton(!radio_view_tabs->isChecked());
//Now load the directory
DW->ChangeDir(dirs[i]); //kick off loading the directory info
}
//Update visibilities
tabChanged(tabBar->currentIndex());
tabBar->setVisible( tabBar->count() > 1 );
if(!invalid.isEmpty()){
QMessageBox::warning(this, tr("Invalid Directories"), tr("The following directories are invalid and could not be opened:")+"\n"+invalid.join(", ") );
}
//Double check that there is at least 1 dir loaded
//qDebug() << "OpenDirs:" << DWLIST.length() << dirs << invalid << tabBar->currentIndex();
if(DWLIST.isEmpty()){ OpenDirs(QStringList()); }
}
