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//------------------------------------------------------------------------------
// <copyright file="ConfigDefinitionUpdates.cs" company="Microsoft">
// Copyright (c) Microsoft Corporation. All rights reserved.
// </copyright>
//------------------------------------------------------------------------------
namespace System.Configuration {
using System.Configuration.Internal;
using System.Collections;
using System.Collections.Generic;
using System.Collections.Specialized;
using System.Configuration;
using System.Globalization;
using System.IO;
using System.Reflection;
using System.Runtime.InteropServices;
using System.Security.Permissions;
using System.Security;
using System.Text;
using System.Xml;
// This is the public type of the override mode enum visible to the API users
// The override mode is an attribute of a <location> tag and controls if the sections inside this tag
// can be defined in child web.config files
public enum OverrideMode {
// Default ( aka Indiferent ) - When specified on a location tag means the location tag will not alter
// the locking mode ( locked or unlocked ). Rather, the locking mode should be picked
// from the <location> tag with the closest parent path in the current file, or the parent file if no such location in the current one,
// or the default for the specific section ( section.OverrideModeDefault )
Inherit = 0,
// Allow overriding in child config files. I.e. unlock the settings for overridiing
Allow = 1,
// Deny overriding of the settings defined in the <location> tag. It is an error for the sections in the <location> tag
// to appear in a child config file. It is not an error for them to appear in another <lcoation> tag in the current file
Deny = 2,
}
// This is a class that abstracts the usage of the override mode setting
internal struct OverrideModeSetting {
private const byte ApiDefinedLegacy = 0x10; // allowOverride was set thourhg the API
private const byte ApiDefinedNewMode = 0x20; // overrideMode was set thourhg the API
private const byte ApiDefinedAny = ApiDefinedLegacy | ApiDefinedNewMode; // allowOverride or overrideMode was set through the API
private const byte XmlDefinedLegacy = 0x40; // allowOverride was defined in the XML
private const byte XmlDefinedNewMode = 0x80; // overrideMode was defined in the XML
private const byte XmlDefinedAny = XmlDefinedLegacy | XmlDefinedNewMode; // overrideMode or allowOverride was defined in the XML
private const byte ModeMask = 0x0f; // logical AND this with the current value to get the mode part only
private byte _mode;
internal static OverrideModeSetting SectionDefault;
internal static OverrideModeSetting LocationDefault;
static OverrideModeSetting() {
SectionDefault = new OverrideModeSetting();
// Default for section is ALLOW ( to be consistent with Whidbey )
SectionDefault._mode = (byte)OverrideMode.Allow;
LocationDefault = new OverrideModeSetting();
// Default for location tags is INHERIT. Note that we do not make the value as existant in the XML or specified by the API
LocationDefault._mode = (byte)OverrideMode.Inherit;
}
static internal OverrideModeSetting CreateFromXmlReadValue(bool allowOverride) {
// Create a mode from the old "allowOverride" attribute in the xml
// The conversion is true -> OverrideMode.Inherit
// The conversion is false -> OverrideMode.Deny
// This is consistent with Whidbey where true means true unless there is a false somewhere above
OverrideModeSetting result = new OverrideModeSetting();
result.SetMode(allowOverride ? OverrideMode.Inherit : OverrideMode.Deny);
result._mode |= XmlDefinedLegacy;
return result;
}
static internal OverrideModeSetting CreateFromXmlReadValue(OverrideMode mode) {
OverrideModeSetting result = new OverrideModeSetting();
result.SetMode(mode);
result._mode |= XmlDefinedNewMode;
return result;
}
internal static OverrideMode ParseOverrideModeXmlValue(string value, XmlUtil xmlUtil) {
// 'value' is the string representation of OverrideMode enum
// Try to parse the string to the enum and generate errors if not possible
switch (value) {
case BaseConfigurationRecord.KEYWORD_OVERRIDEMODE_INHERIT:
return OverrideMode.Inherit;
case BaseConfigurationRecord.KEYWORD_OVERRIDEMODE_ALLOW:
return OverrideMode.Allow;
case BaseConfigurationRecord.KEYWORD_OVERRIDEMODE_DENY:
return OverrideMode.Deny;
default:
throw new ConfigurationErrorsException(
SR.GetString(SR.Config_section_override_mode_attribute_invalid),
xmlUtil);
}
}
internal static bool CanUseSameLocationTag(OverrideModeSetting x, OverrideModeSetting y) {
// This function tells if the two OverrideModeSettings are compatible enough to be used in only one location tag
// or each of them should go to a separate one
// The rules here are ( in order of importance )
// 1. The effective mode is the same ( we will use only the new OverrideMode to compare )
// 2. When the mode was changed( i.e. API change ) - both must be changed the same way ( i.e. using either allowOverride or OverrideMode )
// 3. When mode was not changed the XML - they must've been the same in the xml ( i.e. allowOverride specified on both, or overrideMode or neither of them )
bool result = false;
result = (x.OverrideMode == y.OverrideMode);
if (result == true) {
result = false;
// Check for an API change for each setting first
// If one mode was set through the API - the other mode has to be set in the same way through the API or has to be using the same type in the xml
// Handle case where "x" was API modified
if ((x._mode & ApiDefinedAny) != 0) {
result = IsMatchingApiChangedLocationTag(x, y);
}
// Handle case where "y" was API modified
else if ((y._mode & ApiDefinedAny) != 0) {
result = IsMatchingApiChangedLocationTag(y, x);
}
// Handle case where neither "x" nor "y" was API modified
else {
// If one of the settings was XML defined - they are a match only if both were XML defined in the same way
if ( ((x._mode & XmlDefinedAny) != 0) ||
((y._mode & XmlDefinedAny) != 0)) {
result = (x._mode & XmlDefinedAny) == (y._mode & XmlDefinedAny);
}
// Neither "x" nor "y" was XML defined - they are a match since they can both go
// to a default <location> with no explicit mode setting written out
else {
result = true;
}
}
}
return result;
}
private static bool IsMatchingApiChangedLocationTag(OverrideModeSetting x, OverrideModeSetting y) {
// x must be a changed through the API setting
// Returns true if x and y can share the same location tag
Debug.Assert((x._mode & ApiDefinedAny) != 0);
bool result = false;
// If "y" was modified through the API as well - the modified setting must be the same ( i.e. allowOvverride or overrideMode must be modified in both settings )
if ((y._mode & ApiDefinedAny) != 0) {
result = (x._mode & ApiDefinedAny) == (y._mode & ApiDefinedAny);
}
// "y" was not API modified - they are still a match if "y" was a XML setting from the same mode
else if ((y._mode & XmlDefinedAny) != 0) {
result = ( (((x._mode & ApiDefinedLegacy) != 0) && ((y._mode & XmlDefinedLegacy) != 0)) || // "x" was API changed in Legacy and "y" was XML defined in Legacy
(((x._mode & ApiDefinedNewMode) != 0) && ((y._mode & XmlDefinedNewMode) != 0))); // "x" was API changed in New and "y" was XML defined in New
}
// "y" was not API or XML modified - since "x" was API modified - they are not a match ( i.e. "y" should go to an <location> with no explicit mode written out )
else {
}
return result;
}
internal bool IsDefaultForSection {
get {
// Returns true if the current value of the overrideMode setting is the default one on a section declaration
// The current default value for a section's overrideMode ( i.e. overrideModeDefault ) is Allow ( see CreateDefaultForSection )
// It would've been nice not to repeat that rule here but since OverrideMode.Inherited means the same in this specific context we have to
// I.e. the default for a section is both Allow and Inherited. In this case they mean the same
OverrideMode mode = OverrideMode;
// Return true if mode is Allow or Inherit
return ((mode == OverrideMode.Allow) || (mode == OverrideMode.Inherit));
}
}
internal bool IsDefaultForLocationTag {
get {
// Returns true if the current setting is the same as the default value for a location tag
// Note that if the setting was an API modified or XmlDefined it is not a default since it
// cannot go to the default <location> tag which does not explicitlly specify a mode
OverrideModeSetting defaultSetting = LocationDefault;
return (defaultSetting.OverrideMode == this.OverrideMode) &&
((_mode & ApiDefinedAny) == 0) &&
((_mode & XmlDefinedAny) == 0);
}
}
internal bool IsLocked {
get { return OverrideMode == OverrideMode.Deny;}
}
internal string LocationTagXmlString {
get {
// Returns the string for this setting which is to be written in the xml <location> tag
string result = String.Empty;
string value = null;
string attrib = null;
bool needToWrite = false;
bool useLegacy = false;
// If there was an API change - it has highest priority
if ((_mode & ApiDefinedAny) != 0) {
// Whichever was changed by the API dictates what is to be written
useLegacy = (_mode & ApiDefinedLegacy) != 0;
needToWrite = true;
Debug.Assert(useLegacy || (_mode & ApiDefinedNewMode) != 0);
}
// It wasn't changed through the API - check if it was read originally from the XML
else if ((_mode & XmlDefinedAny) != 0) {
// Whatever was defined in the XML is to be written out
useLegacy = (_mode & XmlDefinedLegacy) != 0;
needToWrite = true;
Debug.Assert(useLegacy || (_mode & XmlDefinedNewMode) != 0);
}
if (needToWrite) {
// Legacy - allowOverride
if (useLegacy) {
attrib = BaseConfigurationRecord.KEYWORD_LOCATION_ALLOWOVERRIDE;
value = AllowOverride ? BaseConfigurationRecord.KEYWORD_TRUE : BaseConfigurationRecord.KEYWORD_FALSE;
}
else {
attrib = BaseConfigurationRecord.KEYWORD_LOCATION_OVERRIDEMODE;
value = OverrideModeXmlValue;
}
result = String.Format(CultureInfo.InvariantCulture, BaseConfigurationRecord.KEYWORD_LOCATION_OVERRIDEMODE_STRING, attrib, value);
}
return result;
}
}
internal string OverrideModeXmlValue {
get {
// Returns the xml (string) value of the current setting for override mode
switch(OverrideMode) {
case OverrideMode.Inherit:
return BaseConfigurationRecord.KEYWORD_OVERRIDEMODE_INHERIT;
case OverrideMode.Allow:
return BaseConfigurationRecord.KEYWORD_OVERRIDEMODE_ALLOW;
case OverrideMode.Deny:
return BaseConfigurationRecord.KEYWORD_OVERRIDEMODE_DENY;
default:
Debug.Assert(false, "Missing xml keyword for OverrideMode enum value");
break;
}
return null;
}
}
// Use this method to change only the value of the setting when not done through the public API
internal void ChangeModeInternal(OverrideMode mode) {
SetMode(mode);
}
// Properties to enable external chnages to the mode.
// Note that those changes will be tracked as made by the public API
// There shouldn't be a reason for those to be used except in this specific case
internal OverrideMode OverrideMode {
get {
return (OverrideMode)(_mode & ModeMask);
}
set {
// Note that changing the mode through the API ( which is the purpose of this setter )
// overrides the setting in the XML ( if any )
// and hence we dont keep a track of it anymore
// Error condition: We do not allow changes to the mode through both AllowOverride and OverrideMode
// If one was changed first we require that API users stick with it
VerifyConsistentChangeModel(ApiDefinedNewMode);
SetMode(value);
_mode |= ApiDefinedNewMode;
}
}
internal bool AllowOverride {
get {
bool result = true;
switch(OverrideMode) {
case OverrideMode.Inherit:
case OverrideMode.Allow:
result = true;
break;
case OverrideMode.Deny:
result = false;
break;
default:
Debug.Assert(false, "Unrecognized OverrideMode");
break;
}
return result;
}
set {
// Note that changing the mode through the API ( which is the purpose of this setter )
// overrides the setting in the XML ( if any )
// and hence we dont keep a track of it anymore
// Error condition: We do not allow changes to the mode through both AllowOverride and OverrideMode
// If one was changed first we require that API users stick with it
VerifyConsistentChangeModel(ApiDefinedLegacy);
SetMode(value ? OverrideMode.Inherit : OverrideMode.Deny);
_mode |= ApiDefinedLegacy;
}
}
private void SetMode(OverrideMode mode) {
_mode = (byte)mode;
}
private void VerifyConsistentChangeModel(byte required) {
// The required API change model ( i.e. was allowOverride used or OverrideMode ) should be consistent
// I.e. its not possible to change both on the same OverrideModeSetting object
byte current = (byte)(_mode & ApiDefinedAny); // Shows whats the current setting: 0 ( none ), ApiDefinedLegacy or ApiDefinedNew
if (current != 0 && current != required) {
throw new ConfigurationErrorsException(SR.GetString(SR.Cannot_change_both_AllowOverride_and_OverrideMode));
}
}
}
}
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