Modules/FAT - Implimentation of FAT_Link, validity unknown but it compiles

[tpg/acess2.git] / KernelLand / Modules / Filesystems / FAT / fatio.c

diff --git a/KernelLand/Modules/Filesystems/FAT/fatio.c b/KernelLand/Modules/Filesystems/FAT/fatio.c
index 43bd622..ab49b30 100644 (file)
--- a/KernelLand/Modules/Filesystems/FAT/fatio.c
+++ b/KernelLand/Modules/Filesystems/FAT/fatio.c
@@ -58,20 +58,22 @@ Uint32 FAT_int_GetFatValue(tFAT_VolInfo *Disk, Uint32 cluster)
  */
 Uint32 FAT_int_AllocateCluster(tFAT_VolInfo *Disk, Uint32 Previous)
 {
-       Uint32  ret = -1, eoc;
-
-       switch(Disk->type)
-       {
-       case FAT12:     eoc = EOC_FAT12;        break;
-       case FAT16:     eoc = EOC_FAT16;        break;
-       case FAT32:     eoc = EOC_FAT32;        break;
-       default:        return 0;
-       }
+       Uint32  ret = -1;
        
        #if CACHE_FAT
        if( Disk->ClusterCount <= giFAT_MaxCachedClusters )
        {
                 int    bFoundCluster = 0;
+               Uint32  eoc;
+
+               switch(Disk->type)
+               {
+               case FAT12:     eoc = EOC_FAT12;        break;
+               case FAT16:     eoc = EOC_FAT16;        break;
+               case FAT32:     eoc = EOC_FAT32;        break;
+                       default:        return 0;
+               }
+               
                Mutex_Acquire(&Disk->lFAT);
                if( Previous != -1 )
                {
@@ -201,6 +203,13 @@ Uint32 FAT_int_AllocateCluster(tFAT_VolInfo *Disk, Uint32 Previous)
 Uint32 FAT_int_FreeCluster(tFAT_VolInfo *Disk, Uint32 Cluster)
 {
        Uint32  ret;
+
+       if( Cluster < 2 || Cluster > Disk->ClusterCount )       // oops?
+       {
+               Log_Notice("FAT", "Cluster 0x%x is out of range (2 ... 0x%x)", 
+                       Cluster, Disk->ClusterCount-1);
+               return -1;
+       }
        
        Mutex_Acquire(&Disk->lFAT);
        #if CACHE_FAT
@@ -213,40 +222,50 @@ Uint32 FAT_int_FreeCluster(tFAT_VolInfo *Disk, Uint32 Cluster)
        else
        {
        #endif
-               Uint32  val;
+               Uint32  val = 0;
                Uint32  ofs = Disk->bootsect.resvSectCount*512;
                switch(Disk->type)
                {
                case FAT12:
                        VFS_ReadAt(Disk->fileHandle, ofs+(Cluster>>1)*3, 3, &val);
+                       val = LittleEndian32(val);
                        if( Cluster & 1 ) {
-                               ret = val & 0xFFF0000;
+                               ret = (val >> 12) & 0xFFF;
                                val &= 0xFFF;
                        }
                        else {
                                ret = val & 0xFFF;
                                val &= 0xFFF000;
                        }
+                       val = LittleEndian32(val);
                        VFS_WriteAt(Disk->fileHandle, ofs+(Cluster>>1)*3, 3, &val);
                        break;
                case FAT16:
                        VFS_ReadAt(Disk->fileHandle, ofs+Cluster*2, 2, &ret);
+                       ret = LittleEndian16(ret);
                        val = 0;
                        VFS_WriteAt(Disk->fileHandle, ofs+Cluster*2, 2, &val);
                        break;
                case FAT32:
                        VFS_ReadAt(Disk->fileHandle, ofs+Cluster*4, 4, &ret);
+                       ret = LittleEndian32(ret);
                        val = 0;
-                       VFS_WriteAt(Disk->fileHandle, ofs+Cluster*2, 2, &val);
+                       VFS_WriteAt(Disk->fileHandle, ofs+Cluster*2, 4, &val);
                        break;
                }
        #if CACHE_FAT
        }
        #endif
        Mutex_Release(&Disk->lFAT);
+       LOG("ret = %07x, eoc = %07x", ret, EOC_FAT12);
+       if(ret == 0) {
+               Log_Notice("FAT", "Cluster 0x%x was already free", Cluster);
+               return -1;
+       }
        if(Disk->type == FAT12 && ret == EOC_FAT12)     ret = -1;
        if(Disk->type == FAT16 && ret == EOC_FAT16)     ret = -1;
        if(Disk->type == FAT32 && ret == EOC_FAT32)     ret = -1;
+       LOG("ret = %07x", ret);
        return ret;
 }
 #endif