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// Licensed to the .NET Foundation under one or more agreements.
// The .NET Foundation licenses this file to you under the MIT license.
using System;
using System.Collections;
using System.Collections.Generic;
using System.Diagnostics;
using System.Diagnostics.CodeAnalysis;
using System.IO;
using System.Security;
namespace System.IO.Packaging
{
/// <summary>
/// Abstract Base class for the Package.
/// This is a part of the Packaging Layer APIs
/// </summary>
public abstract class Package : IDisposable
{
#region Protected Constructor
/// <summary>
/// Protected constructor for the abstract Base class.
/// This is the current contract between the subclass and the base class
/// If we decide some registration mechanism then this might change
/// </summary>
/// <param name="openFileAccess"></param>
/// <exception cref="ArgumentOutOfRangeException">If FileAccess enumeration does not have one of the valid values</exception>
protected Package(FileAccess openFileAccess)
{
ThrowIfFileAccessInvalid(openFileAccess);
_openFileAccess = openFileAccess;
//PackUriHelper.ValidatedPartUri implements the IComparable interface.
_partList = new SortedList<PackUriHelper.ValidatedPartUri, PackagePart>(); // initial default is zero
_partCollection = null;
_disposed = false;
}
#endregion Protected Constructor
#region Public Properties
/// <summary>
/// Gets the FileAccess with which the package was opened. This is a read only property.
/// This property gets set when the package is opened.
/// </summary>
/// <value>FileAccess</value>
/// <exception cref="ObjectDisposedException">If this Package object has been disposed</exception>
public FileAccess FileOpenAccess
{
get
{
ThrowIfObjectDisposed();
return _openFileAccess;
}
}
/// <summary>
/// The package properties are a subset of the standard OLE property sets
/// SummaryInformation and DocumentSummaryInformation, and include such properties
/// as Title and Subject.
/// </summary>
/// <exception cref="ObjectDisposedException">If this Package object has been disposed</exception>
public PackageProperties PackageProperties
{
get
{
ThrowIfObjectDisposed();
return _packageProperties ??= new PartBasedPackageProperties(this);
}
}
#endregion Public Properties
#region Public Methods
#region OpenOnFileMethods
/// <summary>
/// Opens a package at the specified Path. This method calls the overload which accepts all the parameters
/// with the following defaults -
/// FileMode - FileMode.OpenOrCreate,
/// FileAccess - FileAccess.ReadWrite
/// FileShare - FileShare.None
/// </summary>
/// <param name="path">Path to the package</param>
/// <returns>Package</returns>
/// <exception cref="ArgumentNullException">If path parameter is null</exception>
public static Package Open(string path)
{
return Open(path, s_defaultFileMode, s_defaultFileAccess, s_defaultFileShare);
}
/// <summary>
/// Opens a package at the specified Path in the given mode. This method calls the overload which
/// accepts all the parameters with the following defaults -
/// FileAccess - FileAccess.ReadWrite
/// FileShare - FileShare.None
/// </summary>
/// <param name="path">Path to the package</param>
/// <param name="packageMode">FileMode in which the package should be opened</param>
/// <returns>Package</returns>
/// <exception cref="ArgumentNullException">If path parameter is null</exception>
/// <exception cref="ArgumentOutOfRangeException">If FileMode enumeration [packageMode] does not have one of the valid values</exception>
public static Package Open(string path, FileMode packageMode)
{
return Open(path, packageMode, s_defaultFileAccess, s_defaultFileShare);
}
/// <summary>
/// Opens a package at the specified Path in the given mode with the specified access. This method calls
/// the overload which accepts all the parameters with the following defaults -
/// FileShare - FileShare.None
/// </summary>
/// <param name="path">Path to the package</param>
/// <param name="packageMode">FileMode in which the package should be opened</param>
/// <param name="packageAccess">FileAccess with which the package should be opened</param>
/// <returns>Package</returns>
/// <exception cref="ArgumentNullException">If path parameter is null</exception>
/// <exception cref="ArgumentOutOfRangeException">If FileMode enumeration [packageMode] does not have one of the valid values</exception>
/// <exception cref="ArgumentOutOfRangeException">If FileAccess enumeration [packageAccess] does not have one of the valid values</exception>
public static Package Open(string path, FileMode packageMode, FileAccess packageAccess)
{
return Open(path, packageMode, packageAccess, s_defaultFileShare);
}
#endregion OpenOnFileMethods
#region OpenOnStreamMethods
/// <summary>
/// Open a package on this stream. This method calls the overload which accepts all the parameters
/// with the following defaults -
/// FileMode - FileMode.Open
/// FileAccess - FileAccess.Read
/// </summary>
/// <param name="stream">Stream on which the package is to be opened</param>
/// <returns>Package</returns>
/// <exception cref="ArgumentNullException">If stream parameter is null</exception>
/// <exception cref="IOException">If package to be created should have readwrite/read access and underlying stream is write only</exception>
/// <exception cref="IOException">If package to be created should have readwrite/write access and underlying stream is read only</exception>
public static Package Open(Stream stream)
{
return Open(stream, s_defaultStreamMode, s_defaultStreamAccess);
}
/// <summary>
/// Open a package on this stream. This method calls the overload which accepts all the parameters
/// with the following defaults -
/// FileAccess - FileAccess.ReadWrite
/// </summary>
/// <param name="stream">Stream on which the package is to be opened</param>
/// <param name="packageMode">FileMode in which the package should be opened.</param>
/// <returns>Package</returns>
/// <exception cref="ArgumentNullException">If stream parameter is null</exception>
/// <exception cref="ArgumentOutOfRangeException">If FileMode enumeration [packageMode] does not have one of the valid values</exception>
/// <exception cref="IOException">If package to be created should have readwrite/read access and underlying stream is write only</exception>
/// <exception cref="IOException">If package to be created should have readwrite/write access and underlying stream is read only</exception>
public static Package Open(Stream stream, FileMode packageMode)
{
//If the user is providing a FileMode, in all the modes, except FileMode.Open,
//its most likely that the user intends to write to the stream.
return Open(stream, packageMode, s_defaultFileAccess);
}
#endregion OpenOnStreamMethods
#region PackagePart Methods
/// <summary>
/// Creates a new part in the package. An empty stream corresponding to this part will be created in the
/// package. If a part with the specified uri already exists then we throw an exception.
/// This methods will call the CreatePartCore method which will create the actual PackagePart in the package.
/// </summary>
/// <param name="partUri">Uri of the PackagePart that is to be added</param>
/// <param name="contentType">ContentType of the stream to be added</param>
/// <returns></returns>
/// <exception cref="ObjectDisposedException">If this Package object has been disposed</exception>
/// <exception cref="IOException">If the package is readonly, it cannot be modified</exception>
/// <exception cref="ArgumentNullException">If partUri parameter is null</exception>
/// <exception cref="ArgumentNullException">If contentType parameter is null</exception>
/// <exception cref="ArgumentException">If partUri parameter does not conform to the valid partUri syntax</exception>
/// <exception cref="InvalidOperationException">If a PackagePart with the given partUri already exists in the Package</exception>
public PackagePart CreatePart(Uri partUri, string contentType)
{
return CreatePart(partUri, contentType, CompressionOption.NotCompressed);
}
/// <summary>
/// Creates a new part in the package. An empty stream corresponding to this part will be created in the
/// package. If a part with the specified uri already exists then we throw an exception.
/// This methods will call the CreatePartCore method which will create the actual PackagePart in the package.
/// </summary>
/// <param name="partUri">Uri of the PackagePart that is to be added</param>
/// <param name="contentType">ContentType of the stream to be added</param>
/// <param name="compressionOption">CompressionOption describing compression configuration
/// for the new part. This compression apply only to the part, it doesn't affect relationship parts or related parts.
/// This parameter is optional. </param>
/// <returns></returns>
/// <exception cref="ObjectDisposedException">If this Package object has been disposed</exception>
/// <exception cref="IOException">If the package is readonly, it cannot be modified</exception>
/// <exception cref="ArgumentNullException">If partUri parameter is null</exception>
/// <exception cref="ArgumentNullException">If contentType parameter is null</exception>
/// <exception cref="ArgumentException">If partUri parameter does not conform to the valid partUri syntax</exception>
/// <exception cref="ArgumentOutOfRangeException">If CompressionOption enumeration [compressionOption] does not have one of the valid values</exception>
/// <exception cref="InvalidOperationException">If a PackagePart with the given partUri already exists in the Package</exception>
public PackagePart CreatePart(Uri partUri,
string contentType,
CompressionOption compressionOption)
{
ThrowIfObjectDisposed();
ThrowIfReadOnly();
if (partUri == null)
throw new ArgumentNullException(nameof(partUri));
if (contentType == null)
throw new ArgumentNullException(nameof(contentType));
ThrowIfCompressionOptionInvalid(compressionOption);
PackUriHelper.ValidatedPartUri validatedPartUri = PackUriHelper.ValidatePartUri(partUri);
if (_partList.ContainsKey(validatedPartUri))
throw new InvalidOperationException(SR.PartAlreadyExists);
// Add the part to the _partList if there is no prefix collision
// Note: This is the only place where we pass a null to this method for the part and if the
// methods returns successfully then we replace the null with an actual part.
AddIfNoPrefixCollisionDetected(validatedPartUri, null /* since we don't have a part yet */);
PackagePart addedPart = CreatePartCore(validatedPartUri,
contentType,
compressionOption);
//Set the entry for this Uri with the actual part
_partList[validatedPartUri] = addedPart;
return addedPart;
}
/// <summary>
/// Returns a part that already exists in the package. If the part
/// Corresponding to the URI does not exist in the package then an exception is
/// thrown. The method calls the GetPartCore method which actually fetches the part.
/// </summary>
/// <param name="partUri"></param>
/// <returns></returns>
/// <exception cref="ObjectDisposedException">If this Package object has been disposed</exception>
/// <exception cref="IOException">If the package is write only, information cannot be retrieved from it</exception>
/// <exception cref="ArgumentNullException">If partUri parameter is null</exception>
/// <exception cref="ArgumentException">If partUri parameter does not conform to the valid partUri syntax</exception>
/// <exception cref="InvalidOperationException">If the requested part does not exists in the Package</exception>
public PackagePart GetPart(Uri partUri)
{
PackagePart? returnedPart = GetPartHelper(partUri);
if (returnedPart == null)
throw new InvalidOperationException(SR.PartDoesNotExist);
else
return returnedPart;
}
/// <summary>
/// This is a convenient method to check whether a given part exists in the
/// package. This will have a default implementation that will try to retrieve
/// the part and then if successful, it will return true.
/// If the custom file format has an easier way to do this, they can override this method
/// to get this information in a more efficient way.
/// </summary>
/// <param name="partUri"></param>
/// <returns></returns>
/// <exception cref="ObjectDisposedException">If this Package object has been disposed</exception>
/// <exception cref="IOException">If the package is write only, information cannot be retrieved from it</exception>
/// <exception cref="ArgumentNullException">If partUri parameter is null</exception>
/// <exception cref="ArgumentException">If partUri parameter does not conform to the valid partUri syntax</exception>
public virtual bool PartExists(Uri partUri)
{
ThrowIfObjectDisposed();
if (partUri == null)
throw new ArgumentNullException(nameof(partUri));
PackUriHelper.ValidatedPartUri validatePartUri = PackUriHelper.ValidatePartUri(partUri);
return _partList.ContainsKey(validatePartUri);
}
/// <summary>
/// This method will do all the house keeping required when a part is deleted
/// Then the DeletePartCore method will be called which will have the actual logic to
/// do the work specific to the underlying file format and will actually delete the
/// stream corresponding to this part. This method does not throw if the specified
/// part does not exist. This is in conformance with the FileInfo.Delete call.
/// </summary>
/// <param name="partUri"></param>
/// <exception cref="ObjectDisposedException">If this Package object has been disposed</exception>
/// <exception cref="IOException">If the package is readonly, it cannot be modified</exception>
/// <exception cref="ArgumentNullException">If partUri parameter is null</exception>
/// <exception cref="ArgumentException">If partUri parameter does not conform to the valid partUri syntax</exception>
public void DeletePart(Uri partUri)
{
ThrowIfObjectDisposed();
ThrowIfReadOnly();
if (partUri == null)
throw new ArgumentNullException(nameof(partUri));
PackUriHelper.ValidatedPartUri validatedPartUri = (PackUriHelper.ValidatedPartUri)PackUriHelper.ValidatePartUri(partUri);
if (_partList.TryGetValue(validatedPartUri, out PackagePart? value))
{
//This will get the actual casing of the part that
//is stored in the partList which is equivalent to the
//partUri provided by the user
validatedPartUri = (PackUriHelper.ValidatedPartUri)value.Uri;
_partList[validatedPartUri].IsDeleted = true;
_partList[validatedPartUri].Close();
//Call the Subclass to delete the part
//!!Important Note: The order of this call is important as one of the
//sub-classes - ZipPackage relies upon the abstract layer to be
//able to provide the ZipPackagePart in order to do the proper
//clean up and delete operation.
//The dependency is in ZipPackagePart.DeletePartCore method.
//Ideally we would have liked to avoid this kind of a restriction
//but due to the current class interfaces and data structure ownerships
//between these objects, it tough to re-design at this point.
DeletePartCore(validatedPartUri);
//Finally remove it from the list of parts in the cache
_partList.Remove(validatedPartUri);
}
else
//If the part is not in memory we still call the underlying layer
//to delete the part if it exists
DeletePartCore(validatedPartUri);
if (PackUriHelper.IsRelationshipPartUri(validatedPartUri))
{
//We clear the in-memory data structure corresponding to that relationship part
//This will ensure that the intention of the user to delete the part, is respected.
//And thus we will not try to recreate it just in case there was some data in the
//memory structure.
Uri owningPartUri = PackUriHelper.GetSourcePartUriFromRelationshipPartUri(validatedPartUri);
//Package-level relationships in /_rels/.rels
if (Uri.Compare(owningPartUri, PackUriHelper.PackageRootUri, UriComponents.SerializationInfoString, UriFormat.UriEscaped, StringComparison.Ordinal) == 0)
{
//Clear any data in memory
this.ClearRelationships();
}
else
{
//Clear any data in memory
if (this.PartExists(owningPartUri))
{
PackagePart owningPart = this.GetPart(owningPartUri);
owningPart.ClearRelationships();
}
}
}
else
{
// remove any relationship part
DeletePart(PackUriHelper.GetRelationshipPartUri(validatedPartUri));
}
}
/// <summary>
/// This returns a collection of all the Parts within the package.
/// </summary>
/// <returns></returns>
/// <exception cref="ObjectDisposedException">If this Package object has been disposed</exception>
/// <exception cref="IOException">If the package is writeonly, no information can be retrieved from it</exception>
public PackagePartCollection GetParts()
{
ThrowIfObjectDisposed();
ThrowIfWriteOnly();
//Ideally we should decide whether we should query the underlying layer for parts based on the
//FileShare enum. But since we do not have that information, currently the design is to just
//query the underlying layer once.
//Note:
//Currently the incremental behavior for GetPart method is not consistent with the GetParts method
//which just queries the underlying layer once.
if (_partCollection == null)
{
PackagePart[] parts = GetPartsCore();
//making sure that we get a valid array
Debug.Assert((parts != null),
"Subclass is expected to return an array [an empty one if there are no parts] as a result of GetPartsCore method call. ");
PackUriHelper.ValidatedPartUri partUri;
//We need this dictionary to detect any collisions that might be present in the
//list of parts that was given to us from the underlying physical layer, as more than one
//partnames can be mapped to the same normalized part.
//Note: We cannot use the _partList member variable, as that gets updated incrementally and so its
//not possible to find the collisions using that list.
//PackUriHelper.ValidatedPartUri implements the IComparable interface.
Dictionary<PackUriHelper.ValidatedPartUri, PackagePart> seenPartUris = new Dictionary<PackUriHelper.ValidatedPartUri, PackagePart>(parts.Length);
for (int i = 0; i < parts.Length; i++)
{
partUri = (PackUriHelper.ValidatedPartUri)parts[i].Uri;
if (seenPartUris.ContainsKey(partUri))
throw new FileFormatException(SR.BadPackageFormat);
else
{
// Add the part to the list of URIs that we have already seen
seenPartUris.Add(partUri, parts[i]);
if (!_partList.ContainsKey(partUri))
{
// Add the part to the _partList if there is no prefix collision
AddIfNoPrefixCollisionDetected(partUri, parts[i]);
}
}
}
_partCollection = new PackagePartCollection(_partList);
}
return _partCollection;
}
#endregion PackagePart Methods
#region IDisposable Methods
/// <summary>
/// Member of the IDisposable interface. This method will clean up all the resources.
/// It calls the Flush method to make sure that all the changes made get persisted.
/// Note - subclasses should only override Dispose(bool) if they have resources to release.
/// See the Design Guidelines for the Dispose() pattern.
/// </summary>
void IDisposable.Dispose()
{
if (!_disposed)
{
try
{
// put our house in order before involving the subclass
// close core properties
// This method will write out the core properties to the stream
// These will get flushed to the disk as a part of the DoFlush operation
_packageProperties?.Close();
// flush relationships
FlushRelationships();
//Write out the Relationship XML for the parts
//These streams will get flushed in the DoClose operation.
DoOperationOnEachPart(DoCloseRelationshipsXml);
// Close all the parts that are currently open
DoOperationOnEachPart(DoClose);
Dispose(true);
}
finally
{
// do this no matter what (handles case of poorly behaving subclass that doesn't call back into Dispose(bool)
_disposed = true;
}
//Since all the resources we care about are freed at this point.
GC.SuppressFinalize(this);
}
}
#endregion IDisposable Methods
#region Other Methods
/// <summary>
/// Closes the package and all the underlying parts and relationships.
/// Calls the Dispose Method, since they have the same semantics
/// </summary>
public void Close()
{
((IDisposable)this).Dispose();
}
/// <summary>
/// Flushes the contents of the parts and the relationships to the package.
/// This method will call the FlushCore method which will do the actual flushing of contents.
/// </summary>
/// <exception cref="ObjectDisposedException">If this Package object has been disposed</exception>
/// <exception cref="IOException">If the package is readonly, it cannot be modified</exception>
public void Flush()
{
ThrowIfObjectDisposed();
ThrowIfReadOnly();
// Flush core properties.
// Write core properties.
// This call will write out the xml for the core properties to the stream
// These properties will get flushed to disk as a part of the DoFlush operation
_packageProperties?.Flush();
// Write package relationships XML to the relationship part stream.
// These will get flushed to disk as a part of the DoFlush operation
FlushRelationships(); // Flush into .rels part.
//Write out the Relationship XML for the parts
//These streams will get flushed in the DoFlush operation.
DoOperationOnEachPart(DoWriteRelationshipsXml);
// Flush all the parts that are currently open.
// This will flush part relationships.
DoOperationOnEachPart(DoFlush);
FlushCore();
}
#endregion Other Methods
#region PackageRelationship Methods
/// <summary>
/// Creates a relationship at the Package level with the Target PackagePart specified as the Uri
/// </summary>
/// <param name="targetUri">Target's URI</param>
/// <param name="targetMode">Enumeration indicating the base uri for the target uri</param>
/// <param name="relationshipType">PackageRelationship type, having uri like syntax that is used to
/// uniquely identify the role of the relationship</param>
/// <returns></returns>
/// <exception cref="ObjectDisposedException">If this Package object has been disposed</exception>
/// <exception cref="IOException">If the package is readonly, it cannot be modified</exception>
/// <exception cref="ArgumentNullException">If parameter "targetUri" is null</exception>
/// <exception cref="ArgumentNullException">If parameter "relationshipType" is null</exception>
/// <exception cref="ArgumentOutOfRangeException">If parameter "targetMode" enumeration does not have a valid value</exception>
/// <exception cref="ArgumentException">If TargetMode is TargetMode.Internal and the targetUri is an absolute Uri </exception>
/// <exception cref="ArgumentException">If relationship is being targeted to a relationship part</exception>
public PackageRelationship CreateRelationship(Uri targetUri, TargetMode targetMode, string relationshipType)
{
return CreateRelationship(targetUri, targetMode, relationshipType, null);
}
/// <summary>
/// Creates a relationship at the Package level with the Target PackagePart specified as the Uri
/// </summary>
/// <param name="targetUri">Target's URI</param>
/// <param name="targetMode">Enumeration indicating the base uri for the target uri</param>
/// <param name="relationshipType">PackageRelationship type, having uri like syntax that is used to
/// uniquely identify the role of the relationship</param>
/// <param name="id">String that conforms to the xsd:ID datatype. Unique across the source's
/// relationships. Null is OK (ID will be generated). An empty string is an invalid XML ID.</param>
/// <returns></returns>
/// <exception cref="ObjectDisposedException">If this Package object has been disposed</exception>
/// <exception cref="IOException">If the package is readonly, it cannot be modified</exception>
/// <exception cref="ArgumentNullException">If parameter "targetUri" is null</exception>
/// <exception cref="ArgumentNullException">If parameter "relationshipType" is null</exception>
/// <exception cref="ArgumentOutOfRangeException">If parameter "targetMode" enumeration does not have a valid value</exception>
/// <exception cref="ArgumentException">If TargetMode is TargetMode.Internal and the targetUri is an absolute Uri </exception>
/// <exception cref="ArgumentException">If relationship is being targeted to a relationship part</exception>
/// <exception cref="System.Xml.XmlException">If parameter "id" is not a valid Xsd Id</exception>
/// <exception cref="System.Xml.XmlException">If an id is provided in the method, and its not unique</exception>
public PackageRelationship CreateRelationship(Uri targetUri, TargetMode targetMode, string relationshipType, string? id)
{
ThrowIfObjectDisposed();
ThrowIfReadOnly();
EnsureRelationships();
//All parameter validation is done in the following call
return _relationships.Add(targetUri, targetMode, relationshipType, id);
}
/// <summary>
/// Deletes a relationship from the Package. This is done based on the
/// relationship's ID. The target PackagePart is not affected by this operation.
/// </summary>
/// <param name="id">The ID of the relationship to delete. An invalid ID will not
/// throw an exception, but nothing will be deleted.</param>
/// <exception cref="ObjectDisposedException">If this Package object has been disposed</exception>
/// <exception cref="IOException">If the package is readonly, it cannot be modified</exception>
/// <exception cref="ArgumentNullException">If parameter "id" is null</exception>
/// <exception cref="System.Xml.XmlException">If parameter "id" is not a valid Xsd Id</exception>
public void DeleteRelationship(string id)
{
ThrowIfObjectDisposed();
ThrowIfReadOnly();
if (id == null)
throw new ArgumentNullException(nameof(id));
InternalRelationshipCollection.ThrowIfInvalidXsdId(id);
EnsureRelationships();
_relationships.Delete(id);
}
/// <summary>
/// Returns a collection of all the Relationships that are
/// owned by the package
/// </summary>
/// <returns></returns>
/// <exception cref="ObjectDisposedException">If this Package object has been disposed</exception>
/// <exception cref="IOException">If the package is write only, no information can be retrieved from it</exception>
public PackageRelationshipCollection GetRelationships()
{
//All the validations for dispose and file access are done in the
//GetRelationshipsHelper method.
return GetRelationshipsHelper(null);
}
/// <summary>
/// Returns a collection of filtered Relationships that are
/// owned by the package
/// The filter string is compared with the type of the relationships
/// in a case sensitive and culture ignorant manner.
/// </summary>
/// <returns></returns>
/// <exception cref="ObjectDisposedException">If this Package object has been disposed</exception>
/// <exception cref="IOException">If the package is write only, no information can be retrieved from it</exception>
/// <exception cref="ArgumentNullException">If parameter "relationshipType" is null</exception>
/// <exception cref="ArgumentException">If parameter "relationshipType" is an empty string</exception>
public PackageRelationshipCollection GetRelationshipsByType(string relationshipType)
{
//These checks are made in the GetRelationshipsHelper as well, but we make them
//here as we need to perform parameter validation
ThrowIfObjectDisposed();
ThrowIfWriteOnly();
if (relationshipType == null)
throw new ArgumentNullException(nameof(relationshipType));
InternalRelationshipCollection.ThrowIfInvalidRelationshipType(relationshipType);
return GetRelationshipsHelper(relationshipType);
}
/// <summary>
/// Retrieve a relationship per ID.
/// </summary>
/// <param name="id">The relationship ID.</param>
/// <returns>The relationship with ID 'id' or throw an exception if not found.</returns>
/// <exception cref="ObjectDisposedException">If this Package object has been disposed</exception>
/// <exception cref="IOException">If the package is write only, no information can be retrieved from it</exception>
/// <exception cref="ArgumentNullException">If parameter "id" is null</exception>
/// <exception cref="System.Xml.XmlException">If parameter "id" is not a valid Xsd Id</exception>
/// <exception cref="InvalidOperationException">If the requested relationship does not exist in the Package</exception>
public PackageRelationship GetRelationship(string id)
{
//All the validations for dispose and file access are done in the
//GetRelationshipHelper method.
PackageRelationship? returnedRelationship = GetRelationshipHelper(id);
if (returnedRelationship == null)
throw new InvalidOperationException(SR.PackageRelationshipDoesNotExist);
else
return returnedRelationship;
}
/// <summary>
/// Returns whether there is a relationship with the specified ID.
/// </summary>
/// <param name="id">The relationship ID.</param>
/// <returns>true iff a relationship with ID 'id' is defined on this source.</returns>
/// <exception cref="ObjectDisposedException">If this Package object has been disposed</exception>
/// <exception cref="IOException">If the package is write only, no information can be retrieved from it</exception>
/// <exception cref="ArgumentNullException">If parameter "id" is null</exception>
/// <exception cref="System.Xml.XmlException">If parameter "id" is not a valid Xsd Id</exception>
public bool RelationshipExists(string id)
{
//All the validations for dispose and file access are done in the
//GetRelationshipHelper method.
return (GetRelationshipHelper(id) != null);
}
#endregion PackageRelationship Methods
#endregion Public Methods
#region Protected Abstract Methods
/// <summary>
/// This method is for custom implementation corresponding to the underlying file format.
/// This method will actually add a new part to the package. An empty part should be
/// created as a result of this call.
/// </summary>
/// <param name="partUri"></param>
/// <param name="contentType"></param>
/// <param name="compressionOption"></param>
/// <returns></returns>
protected abstract PackagePart CreatePartCore(Uri partUri,
string contentType,
CompressionOption compressionOption);
/// <summary>
/// This method is for custom implementation corresponding to the underlying file format.
/// This method will actually return the part after reading the actual physical bits.
/// If the PackagePart does not exists in the underlying package then this method should return a null.
/// This method must not throw an exception if a part does not exist.
/// </summary>
/// <param name="partUri"></param>
/// <returns></returns>
protected abstract PackagePart? GetPartCore(Uri partUri);
/// <summary>
/// This method is for custom implementation corresponding to the underlying file format.
/// This method will actually delete the part from the underlying package.
/// This method should not throw if the specified part does not exist.
/// This is in conformance with the FileInfo.Delete call.
/// </summary>
/// <param name="partUri"></param>
protected abstract void DeletePartCore(Uri partUri);
/// <summary>
/// This method is for custom implementation corresponding to the underlying file format.
/// This is the method that knows how to get the actual parts. If there are no parts,
/// this method should return an empty array.
/// </summary>
/// <returns></returns>
protected abstract PackagePart[] GetPartsCore();
/// <summary>
/// This method is for custom implementation corresponding to the underlying file format.
/// This method should be used to dispose the resources that are specific to the file format.
/// Also everything should be flushed to the disc before closing the package.
/// </summary>
/// <remarks>Subclasses that manage non-memory resources should override this method and free these resources.
/// Any override should be careful to always call base.Dispose(disposing) to ensure orderly cleanup.</remarks>
protected virtual void Dispose(bool disposing)
{
if (!_disposed && disposing)
{
_partList?.Clear();
if (_packageProperties != null)
{
_packageProperties.Dispose();
_packageProperties = null;
}
//release objects
_partList = null!;
_partCollection = null;
_relationships = null;
_disposed = true;
}
}
/// <summary>
/// This method is for custom implementation corresponding to the underlying file format.
/// This method flushes the contents of the package to the disc.
/// </summary>
protected abstract void FlushCore();
#endregion Protected Abstract Methods
#region Internal Properties
#endregion Internal Properties
#region Internal Methods
//If the container is readonly then we cannot add/delete to it
internal void ThrowIfReadOnly()
{
if (_openFileAccess == FileAccess.Read)
throw new IOException(SR.CannotModifyReadOnlyContainer);
}
// If the container is writeonly, parts cannot be retrieved from it
internal void ThrowIfWriteOnly()
{
if (_openFileAccess == FileAccess.Write)
throw new IOException(SR.CannotRetrievePartsOfWriteOnlyContainer);
}
// return true to continue
internal delegate bool PartOperation(PackagePart p);
internal static void ThrowIfFileModeInvalid(FileMode mode)
{
//We do the enum check as suggested by the following condition for performance reasons.
if (mode < FileMode.CreateNew || mode > FileMode.Append)
throw new ArgumentOutOfRangeException(nameof(mode));
}
internal static void ThrowIfFileAccessInvalid(FileAccess access)
{
//We do the enum check as suggested by the following condition for performance reasons.
if (access < FileAccess.Read || access > FileAccess.ReadWrite)
throw new ArgumentOutOfRangeException(nameof(access));
}
internal static void ThrowIfCompressionOptionInvalid(CompressionOption compressionOption)
{
//We do the enum check as suggested by the following condition for performance reasons.
if (compressionOption < CompressionOption.NotCompressed || compressionOption > CompressionOption.SuperFast)
throw new ArgumentOutOfRangeException(nameof(compressionOption));
}
/// <summary>
/// </summary>
/// <param name="path">Path to the package.</param>
/// <param name="packageMode">FileMode in which the package should be opened.</param>
/// <param name="packageAccess">FileAccess with which the package should be opened.</param>
/// <param name="packageShare">FileShare with which the package is opened.</param>
/// <returns>Package</returns>
/// <exception cref="ArgumentNullException">If path parameter is null</exception>
/// <exception cref="ArgumentOutOfRangeException">If FileAccess enumeration [packageAccess] does not have one of the valid values</exception>
/// <exception cref="ArgumentOutOfRangeException">If FileMode enumeration [packageMode] does not have one of the valid values</exception>
public static Package Open(
string path,
FileMode packageMode,
FileAccess packageAccess,
FileShare packageShare)
{
if (path is null)
{
throw new ArgumentNullException(nameof(path));
}
ThrowIfFileModeInvalid(packageMode);
ThrowIfFileAccessInvalid(packageAccess);
if (packageMode == FileMode.OpenOrCreate && packageAccess != FileAccess.ReadWrite)
throw new ArgumentException(SR.UnsupportedCombinationOfModeAccess);
if (packageMode == FileMode.Open && packageAccess == FileAccess.Write)
throw new ArgumentException(SR.UnsupportedCombinationOfModeAccess);
if (packageMode == FileMode.Truncate && packageAccess == FileAccess.Read)
throw new ArgumentException(SR.UnsupportedCombinationOfModeAccess);
if (packageMode == FileMode.Truncate)
throw new NotSupportedException(SR.UnsupportedCombinationOfModeAccess);
//Note: FileShare enum is not being verified at this stage, as we do not interpret the flag in this
//code at all and just pass it on to the next layer, where the necessary validation can be
//performed. Also, there is no meaningful way to check this parameter at this layer, as the
//FileShare enumeration is a set of flags and flags/Bit-fields can be combined using a
//bitwise OR operation to create different values, and validity of these values is specific to
//the actual physical implementation.
//Verify if this is valid for filenames
FileInfo packageFileInfo = new FileInfo(path);
Package? package = null;
try
{
package = new ZipPackage(packageFileInfo.FullName, packageMode, packageAccess, packageShare);
package._openFileMode = packageMode;
//We need to get all the parts if any exists from the underlying file
//so that we have the names in the Normalized form in our in-memory
//data structures.
//Note: If ever this call is removed, each individual call to GetPartCore,
//may result in undefined behavior as the underlying ZipArchive, maintains the
//files list as being case-sensitive.
if (package.FileOpenAccess == FileAccess.ReadWrite || package.FileOpenAccess == FileAccess.Read)
package.GetParts();
}
catch
{
package?.Close();
throw;
}
return package;
}
/// <summary>
/// </summary>
/// <param name="stream">Stream on which the package is created</param>
/// <param name="packageMode">FileMode in which the package is to be opened</param>
/// <param name="packageAccess">FileAccess on the package that is opened</param>
/// <returns>Package</returns>
/// <exception cref="ArgumentNullException">If stream parameter is null</exception>
/// <exception cref="ArgumentOutOfRangeException">If FileMode enumeration [packageMode] does not have one of the valid values</exception>
/// <exception cref="ArgumentOutOfRangeException">If FileAccess enumeration [packageAccess] does not have one of the valid values</exception>
/// <exception cref="IOException">If package to be created should have readwrite/read access and underlying stream is write only</exception>
/// <exception cref="IOException">If package to be created should have readwrite/write access and underlying stream is read only</exception>
public static Package Open(Stream stream, FileMode packageMode, FileAccess packageAccess)
{
if (stream is null)
{
throw new ArgumentNullException(nameof(stream));
}
Package? package = null;
try
{
// Today the Open(Stream) method is purely used for streams of Zip file format as
// that is the default underlying file format mapper implemented.
package = new ZipPackage(stream, packageMode, packageAccess);
//We need to get all the parts if any exists from the underlying file
//so that we have the names in the Normalized form in our in-memory
//data structures.
//Note: If ever this call is removed, each individual call to GetPartCore,
//may result in undefined behavior as the underlying ZipArchive, maintains the
//files list as being case-sensitive.
if (package.FileOpenAccess == FileAccess.ReadWrite || package.FileOpenAccess == FileAccess.Read)
package.GetParts();
}
catch
{
package?.Close();
throw;
}
return package;
}
//------------------------------------------------------
//
// Internal Events
//
//------------------------------------------------------
// None
//------------------------------------------------------
//
// Private Methods
//
//------------------------------------------------------
#endregion Internal Methods
#region Private Methods
// This method is only when new part is added to the Package object.
// This method will throw an exception if the name of the part being added is a
// prefix of the name of an existing part.
// Example - Say the following parts exist in the package
// 1. /abc.xaml
// 2. /xyz/pqr/a.jpg
// As an example - Adding any of the following parts will throw an exception -
// 1. /abc.xaml/new.xaml
// 2. /xyz/pqr
private void AddIfNoPrefixCollisionDetected(PackUriHelper.ValidatedPartUri partUri, PackagePart? part)
{
//Add the Normalized Uri to the sorted _partList tentatively to see where it will get inserted
_partList.Add(partUri, part!);
//Get the index of the entry at which this part was added
int index = _partList.IndexOfKey(partUri);
Debug.Assert(index >= 0, "Given uri must be present in the dictionary");
string normalizedPartName = partUri.NormalizedPartUriString;
string? precedingPartName = null;
string? followingPartName = null;
if (index > 0)
{
precedingPartName = _partList.Keys[index - 1].NormalizedPartUriString;
}
if (index < _partList.Count - 1)
{
followingPartName = _partList.Keys[index + 1].NormalizedPartUriString;
}
if ((precedingPartName != null
&& normalizedPartName.StartsWith(precedingPartName, StringComparison.Ordinal)
&& normalizedPartName.Length > precedingPartName.Length
&& normalizedPartName[precedingPartName.Length] == PackUriHelper.ForwardSlashChar) ||
(followingPartName != null
&& followingPartName.StartsWith(normalizedPartName, StringComparison.Ordinal)
&& followingPartName.Length > normalizedPartName.Length
&& followingPartName[normalizedPartName.Length] == PackUriHelper.ForwardSlashChar))
{
//Removing the invalid entry from the _partList.
_partList.Remove(partUri);
throw new InvalidOperationException(SR.PartNamePrefixExists);
}
}
//Throw if the object is in a disposed state
private void ThrowIfObjectDisposed()
{
if (_disposed)
throw new ObjectDisposedException(null, SR.ObjectDisposed);
}
[MemberNotNull(nameof(_relationships))]
private void EnsureRelationships()
{
// once per package
_relationships ??= new InternalRelationshipCollection(this);
}
//Delete All Package-level Relationships
private void ClearRelationships()
{
_relationships?.Clear();
}
//Flush the relationships at package level
private void FlushRelationships()
{
// flush relationships
if (_relationships != null && _openFileAccess != FileAccess.Read)
{
_relationships.Flush();
}
}
//We do the close or the flush operation per part
private void DoOperationOnEachPart(PartOperation operation)
{
//foreach (PackagePart p in _partList.Values)
// p.Close(); - this throws
// Make local copy of part names to prevent exception during enumeration when
// a new relationship part gets created (flushing relationships can cause part creation).
// This code throws in such a case:
//
// foreach (PackagePart p in _partList.Values)
// p.Flush();
//
if (_partList.Count > 0)
{
int partCount = 0;
PackUriHelper.ValidatedPartUri[] partKeys = new PackUriHelper.ValidatedPartUri[_partList.Keys.Count];
foreach (PackUriHelper.ValidatedPartUri uri in _partList.Keys)
{
partKeys[partCount++] = uri;
}
// this throws an exception in certain cases (when a part has been deleted)
//
// _partList.Keys.CopyTo(keys, 0);
for (int i = 0; i < partKeys.Length; i++)
{
// Some of these may disappear during above close because the list contains "relationship parts"
// and these are removed if their parts' relationship collection is empty
// This fails:
// _partList[keys[i]].Flush();
if (_partList.TryGetValue(partKeys[i], out PackagePart? p))
{
if (!operation(p))
break;
}
}
}
}
//We needed to separate the rels parts from the other parts
//because if a rels part for a part occurred earlier than the part itself in the array,
//the rels part would be closed and then when close the part and try to persist the relationships
//for the particular part, it would throw an exception
private bool DoClose(PackagePart p)
{
if (!p.IsClosed)
{
if (PackUriHelper.IsRelationshipPartUri(p.Uri) && PackUriHelper.ComparePartUri(p.Uri, PackageRelationship.ContainerRelationshipPartName) != 0)
{
//First we close the source part.
//Note - we can safely do this as DoClose is being called on all parts. So ultimately we will end up
//closing the source part as well.
//This logic only takes care of out of order parts.
PackUriHelper.ValidatedPartUri owningPartUri =
(PackUriHelper.ValidatedPartUri)PackUriHelper.GetSourcePartUriFromRelationshipPartUri(p.Uri);
//If the source part for this rels part exists then we close it.
if (_partList.TryGetValue(owningPartUri, out PackagePart? sourcePart))
sourcePart.Close();
}
p.Close();
}
return true;
}
private bool DoFlush(PackagePart p)
{
p.Flush();
return true;
}
private bool DoWriteRelationshipsXml(PackagePart p)
{
if (!p.IsRelationshipPart)
{
p.FlushRelationships();
}
return true;
}
private bool DoCloseRelationshipsXml(PackagePart p)
{
if (!p.IsRelationshipPart)
{
p.CloseRelationships();
}
return true;
}
private PackagePart? GetPartHelper(Uri partUri)
{
ThrowIfObjectDisposed();
ThrowIfWriteOnly();
if (partUri == null)
throw new ArgumentNullException(nameof(partUri));
PackUriHelper.ValidatedPartUri validatePartUri = PackUriHelper.ValidatePartUri(partUri);
if (_partList.TryGetValue(validatePartUri, out PackagePart? value))
{
return value;
}
else
{
//Ideally we should decide whether we should query the underlying layer for the part based on the
//FileShare enum. But since we do not have that information, currently the design is to always
//ask the underlying layer, this allows for incremental access to the package.
//Note:
//Currently this incremental behavior for GetPart is not consistent with the GetParts method
//which just queries the underlying layer once.
PackagePart? returnedPart = GetPartCore(validatePartUri);
if (returnedPart != null)
{
// Add the part to the _partList if there is no prefix collision
AddIfNoPrefixCollisionDetected(validatePartUri, returnedPart);
}
return returnedPart;
}
}
/// <summary>
/// Retrieve a relationship per ID.
/// </summary>
/// <param name="id">The relationship ID.</param>
/// <returns>The relationship with ID 'id' or null if not found.</returns>
private PackageRelationship? GetRelationshipHelper(string id)
{
ThrowIfObjectDisposed();
ThrowIfWriteOnly();
if (id == null)
throw new ArgumentNullException(nameof(id));
InternalRelationshipCollection.ThrowIfInvalidXsdId(id);
EnsureRelationships();
return _relationships.GetRelationship(id);
}
/// <summary>
/// Returns a collection of all the Relationships that are
/// owned by the package based on the filter string.
/// </summary>
/// <returns></returns>
private PackageRelationshipCollection GetRelationshipsHelper(string? filterString)
{
ThrowIfObjectDisposed();
ThrowIfWriteOnly();
EnsureRelationships();
//Internally null is used to indicate that no filter string was specified and
//and all the relationships should be returned.
return new PackageRelationshipCollection(_relationships, filterString);
}
#endregion Private Methods
#region Private Members
// Default values for the Package.Open method overloads
private const FileMode s_defaultFileMode = FileMode.OpenOrCreate;
private const FileAccess s_defaultFileAccess = FileAccess.ReadWrite;
private const FileShare s_defaultFileShare = FileShare.None;
private const FileMode s_defaultStreamMode = FileMode.Open;
private const FileAccess s_defaultStreamAccess = FileAccess.Read;
private readonly FileAccess _openFileAccess;
private FileMode _openFileMode;
private bool _disposed;
private SortedList<PackUriHelper.ValidatedPartUri, PackagePart> _partList;
private PackagePartCollection? _partCollection;
private InternalRelationshipCollection? _relationships;
private PartBasedPackageProperties? _packageProperties;
#endregion Private Members
}
}
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