Merge pull request #2783 from CosmosOS/fix/fat32Read

FAT32 Read fix
CosmosOS · Sep 27, 2023 · 64db699 · 64db699
2 parents 1f73caf + d8d292e
commit 64db699
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Showing 4 changed files with 27 additions and 7 deletions.
diff --git a/Build/VMWare/Workstation/FilesystemTest.vmdk b/Build/VMWare/Workstation/FilesystemTest.vmdk
diff --git a/Tests/Cosmos.TestRunner.Core/Engine.Run.cs b/Tests/Cosmos.TestRunner.Core/Engine.Run.cs
@@ -43,7 +43,7 @@ private bool ExecuteKernel(
             else
             {
                 xHarddiskPath = Path.Combine(workingDirectory, "Harddisk.vmdk");
-                var xOriginalHarddiskPath = Path.Combine(GetCosmosUserkitFolder(), "Build", "VMware", "Workstation", "Filesystem.vmdk");
+                var xOriginalHarddiskPath = Path.Combine(GetCosmosUserkitFolder(), "Build", "VMware", "Workstation", "FilesystemTest.vmdk");
                 File.Copy(xOriginalHarddiskPath, xHarddiskPath);
             }
 

diff --git a/Tests/Kernels/Cosmos.Kernel.Tests.Fat/System.IO/FileTest.cs b/Tests/Kernels/Cosmos.Kernel.Tests.Fat/System.IO/FileTest.cs
diff --git a/source/Cosmos.System2/FileSystem/FAT/FatFileSystem.cs b/source/Cosmos.System2/FileSystem/FAT/FatFileSystem.cs
@@ -1,4 +1,5 @@
-// #define COSMOSDEBUG
+
+// #define COSMOSDEBUG
 
 using System;
 using System.Collections.Generic;
@@ -145,6 +146,7 @@ public uint[] GetFatChain(uint aFirstEntry, long aDataSize = 0)
                     }
                 }
 
+                /* 
                 string xChain = "";
                 for (int i = 0; i < xReturn.Length; i++)
                 {
@@ -156,6 +158,7 @@ public uint[] GetFatChain(uint aFirstEntry, long aDataSize = 0)
                 }
                 Global.Debugger.SendInternal("Fat xChain:");
                 Global.Debugger.SendInternal(xChain);
+                */
 
                 SetFatEntry(xCurrentEntry, FatEntryEofValue());
 
@@ -385,7 +388,8 @@ internal void GetFatEntry(uint aEntryNumber, out uint aValue)
                         break;
 
                     case FatTypeEnum.Fat32:
-                        aValue = BitConverter.ToUInt32(xData, (int)xEntryOffset) & 0x0FFFFFFF;
+                        int localOffset = (int)(xEntryOffset % mFileSystem.BytesPerSector);
+                        aValue = BitConverter.ToUInt32(xData, localOffset) & 0x0FFFFFFF;
                         break;
 
                     default:
@@ -414,23 +418,23 @@ internal void SetFatEntry(ulong aEntryNumber, ulong aValue)
                 ulong xEntryOffset = aEntryNumber * xEntrySize;
 
                 ulong xSector = xEntryOffset / mFileSystem.BytesPerSector;
-                //ulong xSectorOffset = (xSector * mFileSystem.BytesPerSector) - xEntryOffset;
+                int localOffset = (int)(xEntryOffset % mFileSystem.BytesPerSector);
 
                 byte[] xData;
                 ReadFatSector(xSector, out xData);
 
                 switch (mFileSystem.mFatType)
                 {
                     case FatTypeEnum.Fat12:
-                        xData.SetUInt16(xEntryOffset, (ushort)aValue);
+                        xData.SetUInt16((ulong)localOffset, (ushort)aValue);
                         break;
 
                     case FatTypeEnum.Fat16:
-                        xData.SetUInt16(xEntryOffset, (ushort)aValue);
+                        xData.SetUInt16((ulong)localOffset, (ushort)aValue);
                         break;
 
                     case FatTypeEnum.Fat32:
-                        xData.SetUInt32(xEntryOffset, (uint)aValue);
+                        xData.SetUInt32((ulong)localOffset, (uint)aValue);
                         break;
 
                     default: