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using System;
using System.Collections.Generic;
using System.Collections.ObjectModel;
using System.Data.Linq.Mapping;
using System.Data.Linq.Provider;
using System.Linq.Expressions;
using System.Diagnostics.CodeAnalysis;
namespace System.Data.Linq.SqlClient {
internal enum SqlParameterType {
Value,
UserArgument,
PreviousResult
}
internal class SqlParameterInfo {
SqlParameter parameter;
object value;
Delegate accessor;
internal SqlParameterInfo(SqlParameter parameter, Delegate accessor) {
this.parameter = parameter;
this.accessor = accessor;
}
internal SqlParameterInfo(SqlParameter parameter, object value) {
this.parameter = parameter;
this.value = value;
}
internal SqlParameterInfo(SqlParameter parameter) {
this.parameter = parameter;
}
internal SqlParameterType Type {
get {
if (this.accessor != null) {
return SqlParameterType.UserArgument;
}
else if (this.parameter.Name == "@ROWCOUNT") {
return SqlParameterType.PreviousResult;
}
else {
return SqlParameterType.Value;
}
}
}
internal SqlParameter Parameter {
get { return this.parameter; }
}
internal Delegate Accessor {
get { return this.accessor; }
}
internal object Value {
get { return this.value; }
}
}
internal class SqlParameterizer {
TypeSystemProvider typeProvider;
SqlNodeAnnotations annotations;
int index;
internal SqlParameterizer(TypeSystemProvider typeProvider, SqlNodeAnnotations annotations) {
this.typeProvider = typeProvider;
this.annotations = annotations;
}
internal ReadOnlyCollection<SqlParameterInfo> Parameterize(SqlNode node) {
return this.ParameterizeInternal(node).AsReadOnly();
}
private List<SqlParameterInfo> ParameterizeInternal(SqlNode node) {
Visitor v = new Visitor(this);
v.Visit(node);
return new List<SqlParameterInfo>(v.currentParams);
}
internal ReadOnlyCollection<ReadOnlyCollection<SqlParameterInfo>> ParameterizeBlock(SqlBlock block) {
SqlParameterInfo rowStatus =
new SqlParameterInfo(
new SqlParameter(typeof(int), typeProvider.From(typeof(int)), "@ROWCOUNT", block.SourceExpression)
);
List<ReadOnlyCollection<SqlParameterInfo>> list = new List<ReadOnlyCollection<SqlParameterInfo>>();
for (int i = 0, n = block.Statements.Count; i < n; i++) {
SqlNode statement = block.Statements[i];
List<SqlParameterInfo> parameters = this.ParameterizeInternal(statement);
if (i > 0) {
parameters.Add(rowStatus);
}
list.Add(parameters.AsReadOnly());
}
return list.AsReadOnly();
}
internal virtual string CreateParameterName() {
return "@p" + this.index++;
}
class Visitor : SqlVisitor {
private SqlParameterizer parameterizer;
internal Dictionary<object, SqlParameterInfo> map;
internal List<SqlParameterInfo> currentParams;
private bool topLevel;
private ProviderType timeProviderType; // for special case handling of DateTime parameters
internal Visitor(SqlParameterizer parameterizer) {
this.parameterizer = parameterizer;
this.topLevel = true;
this.map = new Dictionary<object, SqlParameterInfo>();
this.currentParams = new List<SqlParameterInfo>();
}
private SqlParameter InsertLookup(SqlValue cp) {
SqlParameterInfo pi = null;
if (!this.map.TryGetValue(cp, out pi)) {
SqlParameter p;
if (this.timeProviderType == null) {
p = new SqlParameter(cp.ClrType, cp.SqlType, this.parameterizer.CreateParameterName(), cp.SourceExpression);
pi = new SqlParameterInfo(p, cp.Value);
}
else {
p = new SqlParameter(cp.ClrType, this.timeProviderType, this.parameterizer.CreateParameterName(), cp.SourceExpression);
pi = new SqlParameterInfo(p, ((DateTime)cp.Value).TimeOfDay);
}
this.map.Add(cp, pi);
this.currentParams.Add(pi);
}
return pi.Parameter;
}
internal override SqlExpression VisitBinaryOperator(SqlBinary bo)
{
//
// Special case to allow DateTime CLR type to be passed as a paramater where
// a SQL type TIME is expected. We do this only for the equality/inequality
// comparisons.
//
switch (bo.NodeType) {
case SqlNodeType.EQ:
case SqlNodeType.EQ2V:
case SqlNodeType.NE:
case SqlNodeType.NE2V: {
SqlDbType leftSqlDbType = ((SqlTypeSystem.SqlType)(bo.Left.SqlType)).SqlDbType;
SqlDbType rightSqlDbType = ((SqlTypeSystem.SqlType)(bo.Right.SqlType)).SqlDbType;
if (leftSqlDbType == rightSqlDbType)
break;
bool isLeftColRef = bo.Left is SqlColumnRef;
bool isRightColRef = bo.Right is SqlColumnRef;
if (isLeftColRef == isRightColRef)
break;
if (isLeftColRef && leftSqlDbType == SqlDbType.Time && bo.Right.ClrType == typeof(DateTime))
this.timeProviderType = bo.Left.SqlType;
else if (isRightColRef && rightSqlDbType == SqlDbType.Time && bo.Left.ClrType == typeof(DateTime))
this.timeProviderType = bo.Left.SqlType;
break;
}
}
base.VisitBinaryOperator(bo);
return bo;
}
internal override SqlSelect VisitSelect(SqlSelect select) {
bool saveTop = this.topLevel;
this.topLevel = false;
select = this.VisitSelectCore(select);
this.topLevel = saveTop;
select.Selection = this.VisitExpression(select.Selection);
return select;
}
internal override SqlUserQuery VisitUserQuery(SqlUserQuery suq) {
bool saveTop = this.topLevel;
this.topLevel = false;
for (int i = 0, n = suq.Arguments.Count; i < n; i++) {
suq.Arguments[i] = this.VisitParameter(suq.Arguments[i]);
}
this.topLevel = saveTop;
suq.Projection = this.VisitExpression(suq.Projection);
return suq;
}
[SuppressMessage("Microsoft.Design", "CA1061:DoNotHideBaseClassMethods", Justification="Unknown reason.")]
internal SqlExpression VisitParameter(SqlExpression expr) {
SqlExpression result = this.VisitExpression(expr);
switch (result.NodeType) {
case SqlNodeType.Parameter:
return (SqlParameter)result;
case SqlNodeType.Value:
// force even literal values to become parameters
return this.InsertLookup((SqlValue)result);
default:
System.Diagnostics.Debug.Assert(false);
return result;
}
}
internal override SqlStoredProcedureCall VisitStoredProcedureCall(SqlStoredProcedureCall spc) {
this.VisitUserQuery(spc);
for (int i = 0, n = spc.Function.Parameters.Count; i < n; i++) {
MetaParameter mp = spc.Function.Parameters[i];
SqlParameter arg = spc.Arguments[i] as SqlParameter;
if (arg != null) {
arg.Direction = this.GetParameterDirection(mp);
if (arg.Direction == ParameterDirection.InputOutput ||
arg.Direction == ParameterDirection.Output) {
// Text, NText and Image parameters cannot be used as output parameters
// so we retype them if necessary.
RetypeOutParameter(arg);
}
}
}
// add default return value
SqlParameter p = new SqlParameter(typeof(int?), this.parameterizer.typeProvider.From(typeof(int)), "@RETURN_VALUE", spc.SourceExpression);
p.Direction = System.Data.ParameterDirection.Output;
this.currentParams.Add(new SqlParameterInfo(p));
return spc;
}
private bool RetypeOutParameter(SqlParameter node) {
if (!node.SqlType.IsLargeType) {
return false;
}
ProviderType newType = this.parameterizer.typeProvider.GetBestLargeType(node.SqlType);
if (node.SqlType != newType) {
node.SetSqlType(newType);
return true;
}
// Since we are dealing with a long out parameter that hasn't been
// retyped, we need to annotate
this.parameterizer.annotations.Add(
node,
new SqlServerCompatibilityAnnotation(
SqlClient.Strings.MaxSizeNotSupported(node.SourceExpression), SqlProvider.ProviderMode.Sql2000));
return false;
}
[SuppressMessage("Microsoft.Performance", "CA1822:MarkMembersAsStatic", Justification="Unknown reason.")]
private System.Data.ParameterDirection GetParameterDirection(MetaParameter p) {
if (p.Parameter.IsRetval) {
return System.Data.ParameterDirection.ReturnValue;
}
else if (p.Parameter.IsOut) {
return System.Data.ParameterDirection.Output;
}
else if (p.Parameter.ParameterType.IsByRef) {
return System.Data.ParameterDirection.InputOutput;
}
else {
return System.Data.ParameterDirection.Input;
}
}
internal override SqlStatement VisitInsert(SqlInsert sin) {
bool saveTop = this.topLevel;
this.topLevel = false;
base.VisitInsert(sin);
this.topLevel = saveTop;
return sin;
}
internal override SqlStatement VisitUpdate(SqlUpdate sup) {
bool saveTop = this.topLevel;
this.topLevel = false;
base.VisitUpdate(sup);
this.topLevel = saveTop;
return sup;
}
internal override SqlStatement VisitDelete(SqlDelete sd) {
bool saveTop = this.topLevel;
this.topLevel = false;
base.VisitDelete(sd);
this.topLevel = saveTop;
return sd;
}
internal override SqlExpression VisitValue(SqlValue value) {
if (this.topLevel || !value.IsClientSpecified || !value.SqlType.CanBeParameter) {
return value;
}
else {
return this.InsertLookup(value);
}
}
internal override SqlExpression VisitClientParameter(SqlClientParameter cp) {
if (cp.SqlType.CanBeParameter) {
SqlParameter p = new SqlParameter(cp.ClrType, cp.SqlType, this.parameterizer.CreateParameterName(), cp.SourceExpression);
this.currentParams.Add(new SqlParameterInfo(p, cp.Accessor.Compile()));
return p;
}
else {
return cp;
}
}
}
}
}
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