Add FileIdenfifier.FromFile

meziantou · Dec 16, 2024 · 52ba93a · 52ba93a
1 parent e822782
commit 52ba93a
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Showing 4 changed files with 37 additions and 3 deletions.
diff --git a/src/Meziantou.Framework.Win32.ChangeJournal/FileIdentifier.cs b/src/Meziantou.Framework.Win32.ChangeJournal/FileIdentifier.cs
@@ -1,6 +1,10 @@
-using System.Globalization;
+using System.ComponentModel;
+using System.Globalization;
 using System.Runtime.CompilerServices;
 using System.Runtime.InteropServices;
+using System.Runtime.Versioning;
+using Microsoft.Win32.SafeHandles;
+using Windows.Win32;
 using Windows.Win32.Storage.FileSystem;
 
 namespace Meziantou.Framework.Win32;
@@ -28,6 +32,26 @@ internal FileIdentifier(FILE_ID_128 parentFileReferenceNumber)
     {
     }
 
+    [SupportedOSPlatform("windows6.0.6000")]
+    public unsafe static FileIdentifier FromFile(string path)
+    {
+        using var handle = File.OpenHandle(path);
+        return FromFile(handle);
+    }
+
+    [SupportedOSPlatform("windows6.0.6000")]
+    public unsafe static FileIdentifier FromFile(SafeFileHandle handle)
+    {
+        var result = new FILE_ID_INFO();
+        var pointer = Unsafe.AsPointer(ref result);
+        if (PInvoke.GetFileInformationByHandleEx(handle, FILE_INFO_BY_HANDLE_CLASS.FileIdInfo, pointer, (uint)sizeof(FILE_ID_INFO)))
+        {
+            return new FileIdentifier(result.FileId);
+        }
+
+        throw new Win32Exception(Marshal.GetLastWin32Error());
+    }
+
     public bool Equals(FileIdentifier other) => _value == other._value;
     public override bool Equals([NotNullWhen(true)] object? obj) => obj is FileIdentifier identifier && Equals(identifier);
     public override int GetHashCode() => _value.GetHashCode();

diff --git a/src/Meziantou.Framework.Win32.ChangeJournal/Meziantou.Framework.Win32.ChangeJournal.csproj b/src/Meziantou.Framework.Win32.ChangeJournal/Meziantou.Framework.Win32.ChangeJournal.csproj
@@ -4,7 +4,7 @@
     <TargetFrameworks>$(LatestTargetFrameworks)</TargetFrameworks>
     <IsTrimmable>false</IsTrimmable>
     <RootNamespace>Meziantou.Framework.Win32</RootNamespace>
-    <Version>3.0.0</Version>
+    <Version>3.1.0</Version>
     <Description>Allow to access the Windows Change Journal to quickly detect changed files</Description>
   </PropertyGroup>
 

diff --git a/src/Meziantou.Framework.Win32.ChangeJournal/NativeMethods.txt b/src/Meziantou.Framework.Win32.ChangeJournal/NativeMethods.txt
@@ -11,4 +11,6 @@ Windows.Win32.System.Ioctl.USN_RECORD_V2
 Windows.Win32.System.Ioctl.USN_RECORD_V3
 Windows.Win32.System.Ioctl.USN_RECORD_V4
 Windows.Win32.System.Ioctl.USN_TRACK_MODIFIED_RANGES
-FLAG_USN_TRACK_MODIFIED_RANGES_ENABLE
+FLAG_USN_TRACK_MODIFIED_RANGES_ENABLE
+GetFileInformationByHandleEx
+FILE_ID_INFO
diff --git a/tests/Meziantou.Framework.Win32.ChangeJournal.Tests/ChangeJournalTests.cs b/tests/Meziantou.Framework.Win32.ChangeJournal.Tests/ChangeJournalTests.cs
@@ -75,6 +75,14 @@ public void NonAdministrator()
         });
     }
 
+    [RunIfFact(FactOperatingSystem.Windows)]
+    public void GetFileIdentifier()
+    {
+        var file = Path.GetTempFileName();
+        var identifier = FileIdentifier.FromFile(file);
+        Assert.NotEqual(default, identifier);
+    }
+
     [Fact]
     public void FileIdentifier128ToString()
     {