CTAOS v6

SysCore/drivers/filesys/fat.c

@@ -0,0 +1,34 @@
+#include "../floppy/floppy.h"
+//#include "vfs.h"
+#include "fat.h"
+
+#include <conio.h>
+
+// Detect what FAT is used
+unsigned FATDetect(unsigned TotalClusters)
+{
+    if (TotalClusters == 0) return 0;
+    if (TotalClusters < 4085) return 12;
+    if (TotalClusters < 65525) return 16;
+    return 32;
+}
+
+
+
+/*FatMountInfo FloppyMount(int drive)
+{
+    FatMountInfo a;
+    FATBootSectorPointer fat = (FATBootSectorPointer)0x7e00;
+    FloppyReadSector((unsigned*)fat, drive, 0);
+
+    // Write mount info
+    a.FATEntrySize = 8;
+    a.FATOffset = 1;
+    a.FATSize = (unsigned)fat->SectorsPerFAT;
+    a.NumberOfRootEntries = (unsigned)fat->NumberOfDirectoryEntries;
+    a.NumberOfSectors = (unsigned)(fat->NumberOfSectors == 0) ? (fat->NumberOfSectorsLong) : (fat->NumberOfSectors);
+    a.RootOffset = (unsigned)(fat->NumberOfFATs)*a.FATSize + 1;
+    a.RootSize = (a.NumberOfRootEntries * 32) / (unsigned)fat->BytesPerSector;
+
+    return a;
+}*/

SysCore/drivers/filesys/fat.h

@@ -0,0 +1,91 @@
+#ifndef __FAT_H__
+#define __FAT_H__
+
+typedef struct {
+    unsigned char   Drive;  //useless
+    unsigned char   FlagsNT;
+    unsigned char   Signature;  // 0x28 or 0x29
+    unsigned        SerialNumber;
+    char            VolumeLabel[11];
+    char            SysIDString[8];    // unreliable
+} __attribute__((packed)) BPB_EXT_16;
+
+
+typedef struct {
+    unsigned        SectorsPerFAT;
+    unsigned short  Flags;
+    unsigned short  Version;
+    unsigned        ClusterOfRootDirectory;
+    unsigned short  ClusterOfFSInfo;
+    unsigned short  ClusterOfBackupBootSector;
+    unsigned char   Reserved[12];   // Should be 0 at format
+    unsigned char   Drive;
+    unsigned char   FlagsNT;
+    unsigned char   Signature;  // 0x28 or 0x29
+    unsigned        SerialNumber;
+    char            VolumeLabel[11];
+    char            SysIDString[8]; // always FAT12
+
+} __attribute__((packed)) BPB_EXT_32;
+
+
+typedef struct {
+    unsigned char   _ignore[3];
+
+    // Bios Parameter Block
+    char            OEMIdentify[8];
+    unsigned short  BytesPerSector;
+    unsigned char   SectorsPerCluster;
+    unsigned short  ReservedSectors;
+    unsigned char   NumberOfFATs;
+    unsigned short  NumberOfDirectoryEntries;
+    unsigned short  NumberOfSectors;
+    unsigned char   MediaDescriptorType;
+    unsigned short  SectorsPerFAT;
+    unsigned short  SectorsPerTrack;
+    unsigned short  HeadsPerCylinder;
+    unsigned        HiddenSectors;
+    unsigned        NumberOfSectorsLong;
+    
+    union {
+        BPB_EXT_16 Ext16;
+        BPB_EXT_32 Ext32;
+    } Extended;
+
+} __attribute__((packed)) FATBootSector, *FATBootSectorPointer;
+
+
+typedef struct {
+    unsigned NumberOfSectors;
+    unsigned SizeOfSector;
+    unsigned FatOffset;
+    unsigned NumberOfRootEntries;
+    unsigned RootOffset;
+    unsigned SizeOfRoot;
+    unsigned SizeOfFat;
+    unsigned SizeOfFatEntry;
+    unsigned SizeOfCluster;
+    void     (*ReadSector)  (void* buffer, int lba);
+} FatMountInfo, *FatMountInfoPointer;
+
+
+typedef struct {
+    char            FileName[8];
+    char            Extension[3];
+    unsigned char   Atributes;
+    unsigned char   Reserved;
+    unsigned char   CreateTimeFine;
+    unsigned short  CreateTime;
+    unsigned short  CreateDate;
+    unsigned short  LastAccessedDate;
+    unsigned short  EAIndex;
+    unsigned short  LastModifiedTime;
+    unsigned short  LastModifiedDate;
+    unsigned short  FirstCluster;
+    unsigned        FileSize;
+} __attribute__((packed)) FatDirectoryEntry, *FatDirectoryEntryPointer;
+
+    
+extern FatMountInfo FloppyMount(int drive);
+
+#endif

SysCore/drivers/filesys/vfs.c

@@ -0,0 +1,98 @@
+#include "vfs.h"
+#define MaxDevices 256
+
+#define ReturnInvalid() { File ret; ret.Type = FileTypeInvalid; return ret;}
+
+unsigned CurrentDevice = 0;
+unsigned DeviceCount = 0;
+
+FileSystemPointer _FileSystems[MaxDevices];
+
+File VFSOpenFile (const char* FileName)
+{
+    unsigned Device = CurrentDevice;
+    
+    // No filename specified.
+    if (!FileName) ReturnInvalid();
+    
+    // File length
+    int len = strlen(FileName);
+    // File name without drive
+    char* Name = 0;
+    
+    // Check if relative or absolute path
+    int i;
+    for (i=0; i < len; i++)
+        if (FileName[i] == ':') {
+            Name = &FileName[i+1];
+            FileName[i] = 0;
+            len = i;
+            }
+            
+    // If absolute path, find device
+    if (Name != 0) {
+        for (i=0; i < MaxDevices; i++)
+            if (_FileSystems[i]) {
+                if (strcmp(_FileSystems[i]->Name, FileName) == 0) Device = i;
+            }
+        }
+    // Drive is nonexistant or current drive not mounted
+    if (i==MaxDevices || !_FileSystems[Device]) ReturnInvalid();
+    
+    // Open file
+    return _FileSystems[Device]->Open((Name) ? Name : FileName);
+}
+
+
+int VFSInstallFileSystem(FileSystemPointer fs)
+{
+    // Sanity check
+    if (!fs) return 0;
+    
+    // Verify device does not exist
+    int i;
+    for (i=0; i < DeviceCount; i++)
+        if (_FileSystems[i]) 
+            if (strcmp (fs->Name, _FileSystems[i]->Name) == 0) return 0;
+            
+    _FileSystems[DeviceCount] = fs; DeviceCount++;
+}
+
+void VFSUninstallFileSystem(FileSystemPointer fs)
+{
+    if (!fs) return;
+    
+    int i;
+    for (i=0; i<DeviceCount; i++)
+        if (_FileSystems[i] == fs) {
+            _FileSystems[i] = 0;
+            return;
+        }
+    
+}
+
+void VFSUninstallFileSystemByName(const char* fs)
+{
+    if (!fs) return;
+
+    int i;
+    for (i=0; i<DeviceCount; i++)
+        if (_FileSystems[i])
+            if (strcmp(_FileSystems[i]->Name, fs) == 0){
+                _FileSystems[i] = 0;
+                return;
+            }
+}
+
+void VFSReadFile (FilePointer f, unsigned char* buffer, unsigned len)
+{
+    if (!f || !_FileSystems[f->Device]) return;
+    _FileSystems[f->Device]->Read (f, buffer, len);
+}
+
+void VFSCloseFile (FilePointer f)
+{
+    if (!f || !_FileSystems[f->Device]) return;
+    _FileSystems[f->Device]->Close(f);
+}
+

SysCore/drivers/filesys/vfs.h

@@ -0,0 +1,57 @@
+/***** vfs.h *********************************************************
+ * (c) 2010 CTA Systems Inc. All rights reserved. Glory To God       *
+ *                                                                   *
+ *         Virtual File System (VFS) Implementation                  *
+ *         ========================================                  *
+ *                                                                   *
+ ************************************************************ cta os */
+#ifndef __VFS__H___
+#define __VFS__H___
+
+#include <time.h>
+
+typedef enum {
+    FileTypeInvalid,
+    FileTypeFile,
+    FileTypeDirectory,
+    FileTypeSymbolicLink
+} FileType;
+
+enum FileFlags {
+    FileFlagReadOnly = 0x1,
+    FileFlagHidden = 0x2,
+    FileFlagSystem = 0x4,
+    FileFlagVolumeID = 0x8,
+    FileFlagDirectory = 0x10,
+    FileFlagArchive = 0x20
+};
+    
+
+typedef struct {
+    char Name[256];
+    FileType Type;
+    unsigned Flags;
+    unsigned Length;
+    unsigned EndOfFile;
+    unsigned ID;
+    unsigned Position, CurrentCluster;
+    unsigned Device;
+    TIME Created;
+    DATE LastAccessed;
+    TIME LastModified;
+} File, *FilePointer;
+
+
+typedef struct {
+    char    Name[256];
+    
+    File    (*Directory) (const char* DirectoryName);
+    void    (*Mount)    ();
+    void    (*Read)     (FilePointer, unsigned char*, unsigned);
+    void    (*Close)    (FilePointer);
+    FILE    (*Open)      (const char*);
+    
+} FileSystem, *FileSystemPointer;
+
+
+#endif