public static RC Savepoint(Context ctx, IPager.SAVEPOINT op, int savepoint)
{
Debug.Assert(op == IPager.SAVEPOINT.RELEASE || op == IPager.SAVEPOINT.ROLLBACK || op == IPager.SAVEPOINT.BEGIN);
Debug.Assert(savepoint >= 0);
RC rc = RC.OK;
if (ctx.VTrans.data != null)
{
for (int i = 0; rc == RC.OK && i < ctx.VTrans.length; i++)
{
VTable vtable = ctx.VTrans[i];
ITableModule itablemodule = vtable.Module.IModule;
if (vtable.IVTable != null && itablemodule.Version >= 2)
{
Func <VTable, int, int> method = null;
switch (op)
{
case IPager.SAVEPOINT.BEGIN:
method = itablemodule.Savepoint;
vtable.Savepoints = savepoint + 1;
break;
case IPager.SAVEPOINT.ROLLBACK:
method = itablemodule.RollbackTo;
break;
default:
method = itablemodule.Release;
break;
}
if (method != null && vtable.Savepoints > savepoint)
{
rc = (RC)method(vtable.IVTable, savepoint);
}
}
}
}
return(rc);
}
public static RC Begin(Context ctx, VTable vtable)
{
// Special case: If ctx->aVTrans is NULL and ctx->nVTrans is greater than zero, then this function is being called from within a
// virtual module xSync() callback. It is illegal to write to virtual module tables in this case, so return SQLITE_LOCKED.
if (InSync(ctx))
{
return(RC.LOCKED);
}
if (vtable == null)
{
return(RC.OK);
}
RC rc = RC.OK;
ITableModule imodule = vtable.IVTable.IModule;
if (imodule.Begin != null)
{
// If pVtab is already in the aVTrans array, return early
for (int i = 0; i < ctx.VTrans.length; i++)
{
if (ctx.VTrans[i] == vtable)
{
return(RC.OK);
}
}
// Invoke the xBegin method. If successful, add the vtab to the sqlite3.aVTrans[] array.
rc = GrowVTrans(ctx);
if (rc == RC.OK)
{
rc = imodule.Begin(vtable.IVTable);
if (rc == RC.OK)
{
AddToVTrans(ctx, vtable);
}
}
}
return(rc);
}
public static RC CreateModule(Context ctx, string name, ITableModule imodule, object aux, Action <object> destroy)
{
RC rc = RC.OK;
MutexEx.Enter(ctx.Mutex);
int nameLength = name.Length;
if (ctx.Modules.Find(name, nameLength, (TableModule)null) != null)
{
rc = SysEx.MISUSE_BKPT();
}
else
{
TableModule module = new TableModule(); //: _tagalloc(ctx, sizeof(TableModule) + nameLength + 1)
if (module != null)
{
var nameCopy = name;
module.Name = nameCopy;
module.IModule = imodule;
module.Aux = aux;
module.Destroy = destroy;
TableModule del = (TableModule)ctx.Modules.Insert(nameCopy, nameLength, module);
Debug.Assert(del == null && del == module);
if (del != null)
{
ctx.MallocFailed = true;
C._tagfree(ctx, ref del);
}
}
}
rc = SysEx.ApiExit(ctx, rc);
if (rc != RC.OK && destroy != null)
{
destroy(aux);
}
MutexEx.Leave(ctx.Mutex);
return(rc);
}
public static FuncDef OverloadFunction(Context ctx, FuncDef def, int argsLength, Expr expr)
{
// Check to see the left operand is a column in a virtual table
if (C._NEVER(expr == null))
{
return(def);
}
if (expr.OP != TK.COLUMN)
{
return(def);
}
Table table = expr.Table;
if (C._NEVER(table == null))
{
return(def);
}
if ((table.TabFlags & TF.Virtual) == 0)
{
return(def);
}
IVTable ivtable = GetVTable(ctx, table).IVTable;
Debug.Assert(ivtable != null);
Debug.Assert(ivtable.IModule != null);
ITableModule imodule = (ITableModule)ivtable.IModule;
if (imodule.FindFunction == null)
{
return(def);
}
// Call the xFindFunction method on the virtual table implementation to see if the implementation wants to overload this function
string lowerName = def.Name;
RC rc = RC.OK;
Action <FuncContext, int, Mem[]> func = null;
object[] args = null;
if (lowerName != null)
{
lowerName = lowerName.ToLowerInvariant();
rc = imodule.FindFunction(ivtable, argsLength, lowerName, func, args);
C._tagfree(ctx, ref lowerName);
}
if (rc == RC.OK)
{
return(def);
}
// Create a new ephemeral function definition for the overloaded function
FuncDef newFunc = new FuncDef();//: (FuncDef*)_tagalloc(ctx, sizeof(FuncDef) + _strlen30(def->Name) + 1, true);
if (newFunc == null)
{
return(def);
}
newFunc = def._memcpy();
newFunc.Name = def.Name;
newFunc.Func = func;
newFunc.UserData = args;
newFunc.Flags |= FUNC.EPHEM;
return(newFunc);
}
