internal void CompileForInternal(string xpath, XmlNamespaceManager names)
{
base.query = null;
xpath = xpath.Trim();
if (xpath.Length == 0)
{
base.query = matchAlwaysFilter;
this.flags |= XPathFilterFlags.AlwaysMatch;
}
else if ((1 == xpath.Length) && ('/' == xpath[0]))
{
base.query = rootFilter.First;
this.flags |= XPathFilterFlags.AlwaysMatch;
}
else
{
ValueDataType type;
OpcodeBlock block = QueryMatcher.CompileForInternalEngine(xpath, names, QueryCompilerFlags.None, out type);
if (this.match)
{
block.Append(new MatchResultOpcode());
}
else
{
block.Append(new QueryResultOpcode());
}
base.query = block.First;
}
this.flags &= ~XPathFilterFlags.IsFxFilter;
}
static XPathQueryMatcher()
{
ValueDataType type;
matchAlwaysFilter = new PushBooleanOpcode(true);
rootFilter = QueryMatcher.CompileForInternalEngine("/", null, QueryCompilerFlags.None, out type);
rootFilter.Append(new MatchResultOpcode());
}
internal void Add(string expression, XmlNamespaceManager names, object item, bool forceExternal)
{
Fx.Assert(null != item, "");
// Compile the new filter
bool compiled = false;
OpcodeBlock codeBlock = new OpcodeBlock();
codeBlock.Append(new NoOpOpcode(OpcodeID.QueryTree));
if (!forceExternal)
{
try
{
ValueDataType returnType = ValueDataType.None;
// Try to compile and merge the compiled query into the query tree
codeBlock.Append(QueryMatcher.CompileForInternalEngine(expression, names, QueryCompilerFlags.InverseQuery, out returnType));
MultipleResultOpcode opcode;
if (!this.match)
{
opcode = new QueryMultipleResultOpcode();
}
else
{
opcode = new MatchMultipleResultOpcode();
}
opcode.AddItem(item);
codeBlock.Append(opcode);
compiled = true;
// Perform SubExpression Elimination
codeBlock = new OpcodeBlock(this.elim.Add(item, codeBlock.First));
this.subExprVars = this.elim.VariableCount;
}
catch (QueryCompileException)
{
// If the filter couldn't be compiled, we drop down to the framework engine
}
}
if (!compiled)
{
codeBlock.Append(QueryMatcher.CompileForExternalEngine(expression, names, item, this.match));
}
// Merge the compiled query into the query tree
QueryTreeBuilder builder = new QueryTreeBuilder();
this.query = builder.Build(this.query, codeBlock);
// To de-merge this filter from the tree, we'll have to walk backwards up the tree... so we
// have to remember the last opcode that is executed on behalf of this filter
this.lastLookup[item] = builder.LastOpcode;
}
internal void Add(string expression, XmlNamespaceManager names, object item, bool forceExternal)
{
bool flag = false;
OpcodeBlock newBlock = new OpcodeBlock();
newBlock.Append(new NoOpOpcode(OpcodeID.QueryTree));
if (!forceExternal)
{
try
{
MultipleResultOpcode opcode;
ValueDataType none = ValueDataType.None;
newBlock.Append(QueryMatcher.CompileForInternalEngine(expression, names, QueryCompilerFlags.InverseQuery, out none));
if (!this.match)
{
opcode = new QueryMultipleResultOpcode();
}
else
{
opcode = new MatchMultipleResultOpcode();
}
opcode.AddItem(item);
newBlock.Append(opcode);
flag = true;
newBlock = new OpcodeBlock(this.elim.Add(item, newBlock.First));
base.subExprVars = this.elim.VariableCount;
}
catch (QueryCompileException)
{
}
}
if (!flag)
{
newBlock.Append(QueryMatcher.CompileForExternalEngine(expression, names, item, this.match));
}
QueryTreeBuilder builder = new QueryTreeBuilder();
base.query = builder.Build(base.query, newBlock);
this.lastLookup[item] = builder.LastOpcode;
}
/// <summary>
/// Compile for the internal engine with default flags
/// By defalt, we compile an xpath to run stand alone, with standard optimizations
/// </summary>
internal void CompileForInternal(string xpath, XmlNamespaceManager names)
{
this.query = null;
xpath = xpath.Trim();
if (0 == xpath.Length)
{
// Empty xpaths always match. Same for xpaths that refer to the root only
// We will evaluate such filters with minimal overhead. However, we
// don't want a null value for this.query, so we stick a dummy value in there
this.query = XPathQueryMatcher.matchAlwaysFilter;
this.flags |= (XPathFilterFlags.AlwaysMatch);
}
else if (1 == xpath.Length && '/' == xpath[0])
{
this.query = XPathQueryMatcher.rootFilter.First;
this.flags |= (XPathFilterFlags.AlwaysMatch);
}
else
{
ValueDataType returnType;
OpcodeBlock codeBlock = QueryMatcher.CompileForInternalEngine(xpath, names, QueryCompilerFlags.None, out returnType);
// Inject a final opcode that will place the query result on the query context
// This query is now ready for execution STAND ALONE
if (this.match)
{
codeBlock.Append(new MatchResultOpcode());
}
else
{
codeBlock.Append(new QueryResultOpcode());
}
this.query = codeBlock.First;
}
this.flags &= ~XPathFilterFlags.IsFxFilter;
}
internal static OpcodeBlock CompileForInternalEngine(string xpath, XmlNamespaceManager ns, QueryCompilerFlags flags, out ValueDataType returnType)
{
return(QueryMatcher.CompileForInternalEngine(xpath, ns, flags, QueryMatcher.defaultFunctionLibs, out returnType));
}
/// <summary>
/// Compile the given filter for evaluation using the internal engine.
/// </summary>
/// <param name="flags">Caller customizes optimizations via the flags parameter</param>
/// <param name="returnType">Every xpath expression has a return type</param>
/// <returns>The opcode block we execute to evaluate</returns>
internal static OpcodeBlock CompileForInternalEngine(XPathMessageFilter filter, QueryCompilerFlags flags, IFunctionLibrary[] functionLibs, out ValueDataType returnType)
{
return(QueryMatcher.CompileForInternalEngine(filter.XPath.Trim(), filter.namespaces, flags, functionLibs, out returnType));
}