Exception type changed for opening FileStream over invalid file name

[danmoseley]

Attempting to create FileStream over \\.\COM56 threw FileNotFoundException but now throws IOException. We should either reverse this or document a breaking change.

Microsoft.NET.PackTool.targets(70,5): error MSB4018: The \"GenerateToolsSettingsFile\" task failed unexpectedly. [C:\h\w\A22A08BF\t\dotnetSdkTests\glh5q3pn.sk4\It_collects_E---795E5A8E\HelloWorld.csproj]
C:\h\w\A22A08BF\p\d\sdk\6.0.100-ci\Sdks\Microsoft.NET.Sdk\targets\Microsoft.NET.PackTool.targets(70,5): error MSB4018: System.IO.IOException: The filename, directory name, or volume label syntax is incorrect. : '\\.\COM56' [C:\h\w\A22A08BF\t\dotnetSdkTests\glh5q3pn.sk4\It_collects_E---795E5A8E\HelloWorld.csproj]
at Microsoft.Win32.SafeHandles.SafeFileHandle.NtCreateFile(String fullPath, FileMode mode, FileAccess access, FileShare share, FileOptions options, Int64 preallocationSize) in System.Private.CoreLib.dll:token 0x6000123+0x112 [C:\h\w\A22A08BF\t\dotnetSdkTests\glh5q3pn.sk4\It_collects_E---795E5A8E\HelloWorld.csproj]
at Microsoft.Win32.SafeHandles.SafeFileHandle.Open(String fullPath, FileMode mode, FileAccess access, FileShare share, FileOptions options, Int64 preallocationSize) in System.Private.CoreLib.dll:token 0x6000122+0x6 [C:\h\w\A22A08BF\t\dotnetSdkTests\glh5q3pn.sk4\It_collects_E---795E5A8E\HelloWorld.csproj]
at System.IO.Strategies.WindowsFileStreamStrategy..ctor(String path, FileMode mode, FileAccess access, FileShare share, FileOptions options, Int64 preallocationSize) in System.Private.CoreLib.dll:token 0x6005e31+0x2b [C:\h\w\A22A08BF\t\dotnetSdkTests\glh5q3pn.sk4\It_collects_E---795E5A8E\HelloWorld.csproj]
at System.IO.Strategies.FileStreamHelpers.ChooseStrategyCore(String path, FileMode mode, FileAccess access, FileShare share, Int32 bufferSize, FileOptions options, Int64 preallocationSize) in System.Private.CoreLib.dll:token 0x6005d93+0x28 [C:\h\w\A22A08BF\t\dotnetSdkTests\glh5q3pn.sk4\It_collects_E---795E5A8E\HelloWorld.csproj]
at System.IO.FileStream..ctor(String path, FileMode mode, FileAccess access, FileShare share, Int32 bufferSize, Boolean useAsync) in System.Private.CoreLib.dll:token 0x60059d2+0x0 [C:\h\w\A22A08BF\t\dotnetSdkTests\glh5q3pn.sk4\It_collects_E---795E5A8E\HelloWorld.csproj]
at System.Xml.XmlWriterSettings.CreateWriter(String outputFileName) in System.Private.Xml.dll:token 0x60016eb+0x28 [C:\h\w\A22A08BF\t\dotnetSdkTests\glh5q3pn.sk4\It_collects_E---795E5A8E\HelloWorld.csproj]
at System.Xml.XmlWriter.Create(String outputFileName, XmlWriterSettings settings) in System.Private.Xml.dll:token 0x6001676+0xa [C:\h\w\A22A08BF\t\dotnetSdkTests\glh5q3pn.sk4\It_collects_E---795E5A8E\HelloWorld.csproj]
at System.Xml.Linq.XDocument.Save(String fileName, SaveOptions options) in System.Private.Xml.Linq.dll:token 0x60001b0+0x3c [C:\h\w\A22A08BF\t\dotnetSdkTests\glh5q3pn.sk4\It_collects_E---795E5A8E\HelloWorld.csproj]
at System.Xml.Linq.XDocument.Save(String fileName) in System.Private.Xml.Linq.dll:token 0x60001ae+0x0 [C:\h\w\A22A08BF\t\dotnetSdkTests\glh5q3pn.sk4\It_collects_E---795E5A8E\HelloWorld.csproj]
at Microsoft.NET.Build.Tasks.GenerateToolsSettingsFile.ExecuteCore() in /_/src/Tasks/Microsoft.NET.Build.Tasks/GenerateToolsSettingsFile.cs:line 29 [C:\h\w\A22A08BF\t\dotnetSdkTests\glh5q3pn.sk4\It_collects_E---795E5A8E\HelloWorld.csproj]
at Microsoft.NET.Build.Tasks.TaskBase.Execute() in /_/src/Tasks/Common/TaskBase.cs:line 38 [C:\h\w\A22A08BF\t\dotnetSdkTests\glh5q3pn.sk4\It_collects_E---795E5A8E\HelloWorld.csproj]
at Microsoft.Build.BackEnd.TaskExecutionHost.Microsoft.Build.BackEnd.ITaskExecutionHost.Execute() in Microsoft.Build.dll:token 0x60015f9+0x23 [C:\h\w\A22A08BF\t\dotnetSdkTests\glh5q3pn.sk4\It_collects_E---795E5A8E\HelloWorld.csproj]
at Microsoft.Build.BackEnd.TaskBuilder.ExecuteInstantiatedTask(ITaskExecutionHost taskExecutionHost, TaskLoggingContext taskLoggingContext, TaskHost taskHost, ItemBucket bucket, TaskExecutionMode howToExecuteTask) in Microsoft.Build.dll:token 0x6001478+0x2b5 

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Issue Details

---

Attempting to create FileStream over \\.\COM56 threw FileNotFoundException but now throws IOException. We should either reverse this or document a breaking change.

Microsoft.NET.PackTool.targets(70,5): error MSB4018: The \"GenerateToolsSettingsFile\" task failed unexpectedly. [C:\h\w\A22A08BF\t\dotnetSdkTests\glh5q3pn.sk4\It_collects_E---795E5A8E\HelloWorld.csproj]
C:\h\w\A22A08BF\p\d\sdk\6.0.100-ci\Sdks\Microsoft.NET.Sdk\targets\Microsoft.NET.PackTool.targets(70,5): error MSB4018: System.IO.IOException: The filename, directory name, or volume label syntax is incorrect. : '\\.\COM56' [C:\h\w\A22A08BF\t\dotnetSdkTests\glh5q3pn.sk4\It_collects_E---795E5A8E\HelloWorld.csproj]
at Microsoft.Win32.SafeHandles.SafeFileHandle.NtCreateFile(String fullPath, FileMode mode, FileAccess access, FileShare share, FileOptions options, Int64 preallocationSize) in System.Private.CoreLib.dll:token 0x6000123+0x112 [C:\h\w\A22A08BF\t\dotnetSdkTests\glh5q3pn.sk4\It_collects_E---795E5A8E\HelloWorld.csproj]
at Microsoft.Win32.SafeHandles.SafeFileHandle.Open(String fullPath, FileMode mode, FileAccess access, FileShare share, FileOptions options, Int64 preallocationSize) in System.Private.CoreLib.dll:token 0x6000122+0x6 [C:\h\w\A22A08BF\t\dotnetSdkTests\glh5q3pn.sk4\It_collects_E---795E5A8E\HelloWorld.csproj]
at System.IO.Strategies.WindowsFileStreamStrategy..ctor(String path, FileMode mode, FileAccess access, FileShare share, FileOptions options, Int64 preallocationSize) in System.Private.CoreLib.dll:token 0x6005e31+0x2b [C:\h\w\A22A08BF\t\dotnetSdkTests\glh5q3pn.sk4\It_collects_E---795E5A8E\HelloWorld.csproj]
at System.IO.Strategies.FileStreamHelpers.ChooseStrategyCore(String path, FileMode mode, FileAccess access, FileShare share, Int32 bufferSize, FileOptions options, Int64 preallocationSize) in System.Private.CoreLib.dll:token 0x6005d93+0x28 [C:\h\w\A22A08BF\t\dotnetSdkTests\glh5q3pn.sk4\It_collects_E---795E5A8E\HelloWorld.csproj]
at System.IO.FileStream..ctor(String path, FileMode mode, FileAccess access, FileShare share, Int32 bufferSize, Boolean useAsync) in System.Private.CoreLib.dll:token 0x60059d2+0x0 [C:\h\w\A22A08BF\t\dotnetSdkTests\glh5q3pn.sk4\It_collects_E---795E5A8E\HelloWorld.csproj]
at System.Xml.XmlWriterSettings.CreateWriter(String outputFileName) in System.Private.Xml.dll:token 0x60016eb+0x28 [C:\h\w\A22A08BF\t\dotnetSdkTests\glh5q3pn.sk4\It_collects_E---795E5A8E\HelloWorld.csproj]
at System.Xml.XmlWriter.Create(String outputFileName, XmlWriterSettings settings) in System.Private.Xml.dll:token 0x6001676+0xa [C:\h\w\A22A08BF\t\dotnetSdkTests\glh5q3pn.sk4\It_collects_E---795E5A8E\HelloWorld.csproj]
at System.Xml.Linq.XDocument.Save(String fileName, SaveOptions options) in System.Private.Xml.Linq.dll:token 0x60001b0+0x3c [C:\h\w\A22A08BF\t\dotnetSdkTests\glh5q3pn.sk4\It_collects_E---795E5A8E\HelloWorld.csproj]
at System.Xml.Linq.XDocument.Save(String fileName) in System.Private.Xml.Linq.dll:token 0x60001ae+0x0 [C:\h\w\A22A08BF\t\dotnetSdkTests\glh5q3pn.sk4\It_collects_E---795E5A8E\HelloWorld.csproj]
at Microsoft.NET.Build.Tasks.GenerateToolsSettingsFile.ExecuteCore() in /_/src/Tasks/Microsoft.NET.Build.Tasks/GenerateToolsSettingsFile.cs:line 29 [C:\h\w\A22A08BF\t\dotnetSdkTests\glh5q3pn.sk4\It_collects_E---795E5A8E\HelloWorld.csproj]
at Microsoft.NET.Build.Tasks.TaskBase.Execute() in /_/src/Tasks/Common/TaskBase.cs:line 38 [C:\h\w\A22A08BF\t\dotnetSdkTests\glh5q3pn.sk4\It_collects_E---795E5A8E\HelloWorld.csproj]
at Microsoft.Build.BackEnd.TaskExecutionHost.Microsoft.Build.BackEnd.ITaskExecutionHost.Execute() in Microsoft.Build.dll:token 0x60015f9+0x23 [C:\h\w\A22A08BF\t\dotnetSdkTests\glh5q3pn.sk4\It_collects_E---795E5A8E\HelloWorld.csproj]
at Microsoft.Build.BackEnd.TaskBuilder.ExecuteInstantiatedTask(ITaskExecutionHost taskExecutionHost, TaskLoggingContext taskLoggingContext, TaskHost taskHost, ItemBucket bucket, TaskExecutionMode howToExecuteTask) in Microsoft.Build.dll:token 0x6001478+0x2b5 

Author:	danmoseley
Assignees:	-
Labels:	area-System.IO, untriaged
Milestone:	-

[danmoseley]

dotnet/sdk#18292 (comment)

when fixed, revert dotnet/sdk@1c1a072

[stephentoub]

cc: @adamsitnik

[adamsitnik]

What we had for invalid path for both FileMode.Open and FileMode.Create:

System.IO.FileNotFoundException: Could not find file '\\.\COM56'.

What we have now:

System.IO.IOException : The filename, directory name, or volume label syntax is incorrect. : '\\.\COM56'

Since IMO getting FileNotFoundException for FileMode.Create is strange (if the file does not exist, it should get created for FileMode.Create) I am going to keep the new behavior and write a breaking change doc.

@stephentoub @danmoseley does that sound good to you?

[adamsitnik]

We have some tests that check the exception type for invalid path:

runtime/src/libraries/System.IO.FileSystem/tests/File/Create.cs

Lines 250 to 259 in 9d771a2

	[Fact]
	[PlatformSpecific(TestPlatforms.Windows)]
	public void WindowsWildCharacterPath_Core()
	{
	DirectoryInfo testDir = Directory.CreateDirectory(GetTestFilePath());
	Assert.ThrowsAny<IOException>(() => Create(Path.Combine(testDir.FullName, "dls;d", "442349-0", "v443094(*)(+*$#$*", new string(Path.DirectorySeparatorChar, 3))));
	Assert.ThrowsAny<IOException>(() => Create(Path.Combine(testDir.FullName, "*")));
	Assert.ThrowsAny<IOException>(() => Create(Path.Combine(testDir.FullName, "Test*t")));
	Assert.ThrowsAny<IOException>(() => Create(Path.Combine(testDir.FullName, "*Tes*t")));
	}

Would it be more natural to throw ArgumentException for invalid paths?

Edit: STATUS_OBJECT_NAME_INVALID is returned by NtCreatFile for all kind of invalid file names: the ones that use restricted names like in this example and names that are too long. So IOException seems to be a better choice than ArgumentException

[danmoseley]

@marklio any thoughts?

@adamsitnik what are the cases that changed - any invalid oath e.g. invalid characters?

[stephentoub]

Is this fallout from the switch to use NtCreateFile?

I'm not seeing a strong rationale here for making a breaking change. FileNotFoundException seems better to me than IOException, and I would not be at all surprised if this actually breaks real code.