From 03ec2f1d27fdcff9a5a8785806fcd8449f2537a9 Mon Sep 17 00:00:00 2001
From: Ketmar Dark <ketmar@ketmar.no-ip.org>
Date: Mon, 18 Apr 2016 09:45:47 +0300
Subject: [PATCH] more sfs refactoring

---
 src/game/Doom2DF.dpr             |   3 +-
 src/sfs/sfs.pas                  | 124 +++---
 src/sfs/sfsMemFS.pas             | 247 -----------
 src/sfs/sfsPlainFS.pas           | 712 ++-----------------------------
 src/sfs/sfsZipFS.pas             |  12 +-
 src/sfs/wadcvt.dpr               |   5 +-
 src/shared/utils.pas             |  31 +-
 src/shared/wadreader.pas         |  79 ++--
 src/{sfs => shared}/xstreams.pas | 223 +++++++---
 src/unused/xstreams_sdl.pas      |  76 ++++
 10 files changed, 406 insertions(+), 1106 deletions(-)
 delete mode 100644 src/sfs/sfsMemFS.pas
 rename src/{sfs => shared}/xstreams.pas (63%)
 create mode 100644 src/unused/xstreams_sdl.pas

diff --git a/src/game/Doom2DF.dpr b/src/game/Doom2DF.dpr
index d885e2b..5a10057 100644
--- a/src/game/Doom2DF.dpr
+++ b/src/game/Doom2DF.dpr
@@ -45,8 +45,7 @@ uses
   sfs in '../sfs/sfs.pas',
   sfsPlainFS in '../sfs/sfsPlainFS.pas',
   sfsZipFS in '../sfs/sfsZipFS.pas',
-  sfsMemFS in '../sfs/sfsMemFS.pas',
-  xstreams in '../sfs/xstreams.pas',
+  xstreams in '../shared/xstreams.pas',
   utils in '../shared/utils.pas',
   wadreader in '../shared/wadreader.pas',
   MAPSTRUCT in '../shared/MAPSTRUCT.pas',
diff --git a/src/sfs/sfs.pas b/src/sfs/sfs.pas
index 157fbac..49f8f76 100644
--- a/src/sfs/sfs.pas
+++ b/src/sfs/sfs.pas
@@ -1,6 +1,6 @@
 // streaming file system (virtual)
-{$MODE DELPHI}
-{.$R-}
+{$MODE OBJFPC}
+{$R+}
 {.$DEFINE SFS_VOLDEBUG}
 unit sfs;
 
@@ -13,33 +13,29 @@ uses
 type
   ESFSError = class(Exception);
 
-  TSFSChar = AnsiChar;
-  TSFSString = AnsiString;
-
   TSFSVolume = class;
 
   TSFSFileInfo = class
   public
     fOwner: TSFSVolume; // òàê, íà âñÿêèé ñëó÷àé
-    fPath: TSFSString;  // ðàçäåëèòåëè êàòàëîãîâ -- "/"; êîðåíü íèêàê íå îáîçíà÷åí, åñëè íå ïóñòîå, îáÿçàíî çàâåðøàåòñÿ "/"
-    fName: TSFSString;  // òîëüêî èìÿ
+    fPath: AnsiString;  // ðàçäåëèòåëè êàòàëîãîâ -- "/"; êîðåíü íèêàê íå îáîçíà÷åí, åñëè íå ïóñòîå, îáÿçàíî çàâåðøàòüñÿ "/"
+    fName: AnsiString;  // òîëüêî èìÿ
     fSize: Int64;       // unpacked
     fOfs: Int64;        // in VFS (many of 'em need this %-)
 
     constructor Create (pOwner: TSFSVolume);
     destructor Destroy (); override;
 
-    property path: TSFSString read fPath;
-    property name: TSFSString read fName;
-    property size: Int64 read fSize;
+    property path: AnsiString read fPath;
+    property name: AnsiString read fName;
+    property size: Int64 read fSize; // can be -1 if size is unknown
   end;
 
   // âèðòóàëüíàÿ ôàéëîâàÿ ñèñòåìà. ÒÎËÜÊÎ ÄËß ×ÒÅÍÈß!
   // òîì ÍÅ ÄÎËÆÅÍ óáèâàòüñÿ íèêàê èíà÷å, ÷åì ïðè ïîìîùè ôàáðèêè!
   TSFSVolume = class
   protected
-    fRC: Integer; // refcounter for other objects
-    fFileName: TSFSString;// îáû÷íî èìÿ îðèãèíàëüíîãî ôàéëà
+    fFileName: AnsiString;// îáû÷íî èìÿ îðèãèíàëüíîãî ôàéëà
     fFileStream: TStream; // îáû÷íî ïîòîê äëÿ ÷òåíèÿ îðèãèíàëüíîãî ôàéëà
     fFiles: TObjectList;  // TSFSFileInfo èëè íàñëåäíèêè
 
@@ -64,7 +60,7 @@ type
     // ýòà ïðîöåäóðà ìîæåò ìåíÿòü fFiles!
     // fPath -- â ïðàâèëüíîé ôîðìå, ñ "/", êîðíåâîé "/" óáèò, ôèíàëüíûé äîáàâëåí.
     // åñëè ôàéë íå íàéäåí, âåðíóòü -1.
-    function FindFile (const fPath, fName: TSFSString): Integer; virtual;
+    function FindFile (const fPath, fName: AnsiString): Integer; virtual;
 
     // âîçâðàùàåò êîëè÷åñòâî ôàéëîâ â fFiles
     function GetFileCount (): Integer; virtual;
@@ -78,7 +74,7 @@ type
 
   public
     // pSt íå îáÿçàòåëüíî çàïîìèíàòü, åñëè îí íå íóæåí.
-    constructor Create (const pFileName: TSFSString; pSt: TStream); virtual;
+    constructor Create (const pFileName: AnsiString; pSt: TStream); virtual;
     // fFileStream óíè÷òîæàòü íåëüçÿ, åñëè îí ðàâåí ïàðàìåòðó pSt êîíñòðóêòîðà.
     destructor Destroy (); override;
 
@@ -92,7 +88,7 @@ type
     function OpenFileByIndex (const index: Integer): TStream; virtual; abstract;
 
     // åñëè íå ñìîãëî îòêóïîðèòü ôàéëî (èëè åù¸ ãäå îøèáëîñü), çàøâûðí¸ò èñêëþ÷åíèå.
-    function OpenFileEx (const fName: TSFSString): TStream; virtual;
+    function OpenFileEx (const fName: AnsiString): TStream; virtual;
 
     property FileCount: Integer read GetFileCount; // ìîæåò âåðíóòü íîëü
     // ìîæåò âîçâðàùàòü NIL.
@@ -114,13 +110,13 @@ type
     // ôàéëà. åñëè íè îäíà ôàáðèêà ïðåôèêñ íå ïðèçíàåò, òî ôàéë íå îòêðîþò.
     // èñïîëüçóåòñÿ äëÿ ñêèïàíèÿ àâòîäåòåêòà.
     // SFS ÍÅ Ñ×ÈÒÀÅÒ ÏÐÅÔÈÊÑÎÌ ÑÒÐÎÊÓ ÊÎÐÎ×Å ÒÐ¨Õ ÑÈÌÂÎËÎÂ!
-    function IsMyVolumePrefix (const prefix: TSFSString): Boolean; virtual; abstract;
+    function IsMyVolumePrefix (const prefix: AnsiString): Boolean; virtual; abstract;
     // ïðîâåðÿåò, ìîæåò ëè ôàáðèêà ñäåëàòü òîì äëÿ äàííîãî ôàéëà.
     // st -- îòêðûòûé äëÿ ÷òåíèÿ ôàéëîâé ïîòîê. óêàçàòåëü ÷òåíèÿ ñòîèò â íà÷àëå.
     // ýòîò ïîòîê íåëüçÿ çàêðûâàòü!
     // prefix: òî, ÷òî áûëî ïåðåäàíî â IsMyVolumePrefix() èëè ''.
     // èñêëþ÷åíèå ñ÷èòàåòñÿ îøèáêîé, âîçâðàò NIL ñ÷èòàåòñÿ îøèáêîé.
-    function Produce (const prefix, fileName: TSFSString; st: TStream): TSFSVolume; virtual; abstract;
+    function Produce (const prefix, fileName: AnsiString; st: TStream): TSFSVolume; virtual; abstract;
     // êîãäà òîì áîëüøå íå íóæåí, îí áóäåò îòäàí ôàáðèêå íà ïåðåðàáîòêó.
     // äàëåå äâèæîê íå áóäåò þçàòü ñåé òîì.
     procedure Recycle (vol: TSFSVolume); virtual; abstract;
@@ -167,10 +163,10 @@ procedure SFSUnregisterVolumeFactory (factory: TSFSVolumeFactory);
 // è îáðàùàòüñÿ êàê "datafile::xxx".
 // "||" ïðåîáðàçóþòñÿ â ïðîñòîé "|" è ðàçäåëèòåëåì íå ñ÷èòàþòñÿ.
 // ïðèíèìàåòñÿ âî âíèìàíèå òîëüêî ïîñëåäíÿÿ òðóáà.
-function SFSAddDataFile (const dataFileName: TSFSString; top: Boolean=false): Boolean;
+function SFSAddDataFile (const dataFileName: AnsiString; top: Boolean=false): Boolean;
 
 // äîáàâèòü ñáîðíèê âðåìåííî
-function SFSAddDataFileTemp (const dataFileName: TSFSString; top: Boolean=false): Boolean;
+function SFSAddDataFileTemp (const dataFileName: AnsiString; top: Boolean=false): Boolean;
 
 // äîáàâèòü â ïîñòîÿííûé ñïèñîê ñáîðíèê èç ïîòîêà ds.
 // åñëè âîçâðàùàåò èñòèíó, òî SFS ñòàíîâèòñÿ âëÿäåëüöåì ïîòîêà ds è ñàìà
@@ -183,21 +179,21 @@ function SFSAddDataFileTemp (const dataFileName: TSFSString; top: Boolean=false)
 // âåðí¸ò ëîæü ïðè îøèáêå.
 // îòêðûâàåò ñáîðíèê èç ïîòîêà. dataFileName -- ÂÈÐÒÓÀËÜÍÎÅ èìÿ.
 // ò.å. íà ñàìîì äåëå òàêîãî ôàéëà ìîæåò è íå áûòü íà äèñêå.
-function SFSAddSubDataFile (const virtualName: TSFSString; ds: TStream; top: Boolean=false): Boolean;
+function SFSAddSubDataFile (const virtualName: AnsiString; ds: TStream; top: Boolean=false): Boolean;
 
 // øâûðÿåòñÿ èñêëþ÷åíèÿìè.
 // åñëè fName íå èìååò óêàçàíèÿ íà ôàéë äàííûõ (ýòî òî, ÷òî îòäåëåíî îò
 // îñòàëüíîãî èìåíè äâîåòî÷èåì), òî èùåì ñíà÷àëà ïî âñåì çàðåãèñòðèðîâàííûì
 // ôàéëàì äàííûõ, ïîòîì â òåêóùåì êàòàëîãå, ïîòîì â êàòàëîãå, îòêóäà ñòàðòîâàëè.
 // åñëè íè÷åãî íå íàøëè, êèäàåì èñêëþ÷åíèå.
-function SFSFileOpenEx (const fName: TSFSString): TStream;
+function SFSFileOpenEx (const fName: AnsiString): TStream;
 
 // ïðè îøèáêå -- NIL, è íèêàêèõ èñêëþ÷åíèé.
-function SFSFileOpen (const fName: TSFSString): TStream;
+function SFSFileOpen (const fName: AnsiString): TStream;
 
 // âîçâðàùàåò NIL ïðè îøèáêå.
 // ïîñëå èñïîëüçîâàíèÿ, íàòóðàëüíî, èòåðàòîð íàäî ãðîõíóòü %-)
-function SFSFileList (const dataFileName: TSFSString): TSFSFileList;
+function SFSFileList (const dataFileName: AnsiString): TSFSFileList;
 
 // çàïðåòèòü îñâîáîæäåíèå âðåìåííûõ òîìîâ (ìîæíî âûçûâàòü ðåêóðñèâíî)
 procedure sfsGCDisable ();
@@ -208,11 +204,11 @@ procedure sfsGCEnable ();
 // for completeness sake
 procedure sfsGCCollect ();
 
-function SFSReplacePathDelims (const s: TSFSString; newDelim: TSFSChar): TSFSString;
+function SFSReplacePathDelims (const s: AnsiString; newDelim: Char): AnsiString;
 
 // ðàçîáðàòü òîëñòîå èìÿ ôàéëà, âåðíóòü âèðòóàëüíîå èìÿ ïîñëåäíåãî ñïèñêà
 // èëè ïóñòóþ ñòîðîêó, åñëè ñïèñêîâ íå áûëî.
-function SFSGetLastVirtualName (const fn: TSFSString): string;
+function SFSGetLastVirtualName (const fn: AnsiString): AnsiString;
 
 // Wildcard matching
 // this code is meant to allow wildcard pattern matches. tt is VERY useful
@@ -230,9 +226,9 @@ function SFSGetLastVirtualName (const fn: TSFSString): string;
 //       'this [e-n]s a [!zy]est' -Would match 'this is a test', but would
 //                                 not match 'this as a yest'
 //
-function WildMatch (pattern, text: TSFSString): Boolean;
-function WildListMatch (wildList, text: TSFSString; delimChar: AnsiChar=':'): Integer;
-function HasWildcards (const pattern: TSFSString): Boolean;
+function WildMatch (pattern, text: AnsiString): Boolean;
+function WildListMatch (wildList, text: AnsiString; delimChar: AnsiChar=':'): Integer;
+function HasWildcards (const pattern: AnsiString): Boolean;
 
 
 var
@@ -248,7 +244,7 @@ var
   // òåêóùåì. êàòàëîãè ðàçäåëÿþòñÿ òðóáîé ("|").
   // <currentdir> çàìåíÿåòñÿ íà òåêóùèé êàòàëîã (ñ çàâåðøàþùèì "/"),
   // <exedir> çàìåíÿåòñÿ íà êàòàëîã, ãäå ñèäèò .EXE (ñ çàâåðøàþùèì "/").
-  sfsDiskDirs: TSFSString = '<currentdir>|<exedir>';
+  sfsDiskDirs: AnsiString = '<currentdir>|<exedir>';
 
 
 implementation
@@ -269,7 +265,7 @@ const
   WILD_CHAR_RANGE_NOT      = '!';
 
 
-function HasWildcards (const pattern: TSFSString): Boolean;
+function HasWildcards (const pattern: AnsiString): Boolean;
 begin
   result :=
     (Pos(WILD_CHAR_ESCAPE, pattern) <> 0) or
@@ -279,7 +275,7 @@ begin
     (Pos(WILD_CHAR_RANGE_OPEN, pattern) <> 0);
 end;
 
-function MatchMask (const pattern: TSFSString; p, pend: Integer; const text: TSFSString; t, tend: Integer): Boolean;
+function MatchMask (const pattern: AnsiString; p, pend: Integer; const text: AnsiString; t, tend: Integer): Boolean;
 var
   rangeStart, rangeEnd: AnsiChar;
   rangeNot, rangeMatched: Boolean;
@@ -367,14 +363,14 @@ begin
 end;
 
 
-function WildMatch (pattern, text: TSFSString): Boolean;
+function WildMatch (pattern, text: AnsiString): Boolean;
 begin
   if pattern <> '' then pattern := AnsiLowerCase(pattern);
   if text <> '' then text := AnsiLowerCase(text);
   result := MatchMask(pattern, 1, -1, text, 1, -1);
 end;
 
-function WildListMatch (wildList, text: TSFSString; delimChar: AnsiChar=':'): Integer;
+function WildListMatch (wildList, text: AnsiString; delimChar: AnsiChar=':'): Integer;
 var
   s, e: Integer;
 begin
@@ -408,7 +404,7 @@ type
   TVolumeInfo = class
     fFactory: TSFSVolumeFactory;
     fVolume: TSFSVolume;
-    fPackName: TSFSString; // äëÿ îäíîãî è òîãî æå ôàéëà áóäåò òîëüêî îäèí òîì!
+    fPackName: AnsiString; // äëÿ îäíîãî è òîãî æå ôàéëà áóäåò òîëüêî îäèí òîì!
     fStream: TStream; // ôàéëîâûé ïîòîê äëÿ ñáîðíèêà
     fPermanent: Boolean; // èñòèíà -- íå áóäåò óãðîáëåíà, åñëè íå îñòàíåòñÿ íè îäíîãî îòêðûòîãî òîìà
     // èñòèíà -- ýòîò òîì áûë ñîçäàí èç ïîòîêà è íå èìååò äèñêîâîãî ôàéëà, ïîòîìó ôàáðèêå áóäåò ïåðåäàíî íå èìÿ ñáîðíèêà, à ïóñòàÿ ñòðîêà
@@ -446,7 +442,7 @@ begin
   begin
     vi := TVolumeInfo(volumes[f]);
     if vi = nil then continue;
-    if (not vi.fPermanent) and (vi.fVolume.fRC = 0) and (vi.fOpenedFilesCount = 0) then
+    if (not vi.fPermanent) and (vi.fOpenedFilesCount = 0) then
     begin
       // this volume probably can be removed
       used := false;
@@ -494,7 +490,7 @@ end;
 // ñîáñòâåííî èìÿ ôàéëà
 // èìÿ âûãëÿäèò êàê:
 // (("sfspfx:")?"datafile::")*"filename"
-procedure SplitFName (const fn: string; out dataFile, fileName: string);
+procedure SplitFName (const fn: AnsiString; out dataFile, fileName: AnsiString);
 var
   f: Integer;
 begin
@@ -513,7 +509,7 @@ begin
 end;
 
 // ñàéäýôôåêò: âûðåçàåò âèðòóàëüíîå èìÿ èç dataFile.
-function ExtractVirtName (var dataFile: string): string;
+function ExtractVirtName (var dataFile: AnsiString): AnsiString;
 var
   f: Integer;
 begin
@@ -541,7 +537,7 @@ end;
 // [sfspfx:]datafile[|virtname]
 // åñëè ïåðåä äâîåòî÷èåì ìåíüøå òð¸õ áóêâ, òî ýòî ñ÷èòàåòñÿ íå ïðåôèêñîì,
 // à èìåíåì äèñêà.
-procedure SplitDataName (const fn: string; out pfx, dataFile, virtName: string);
+procedure SplitDataName (const fn: AnsiString; out pfx, dataFile, virtName: AnsiString);
 var
   f: Integer;
 begin
@@ -557,7 +553,7 @@ end;
 
 // íàéòè ïðîèçâîäèòåëÿ äëÿ ýòîãî ôàéëà (åñëè ôàéë óæå îòêðûò).
 // onlyPerm: òîëüêî "ïîñòîÿííûå" ïðîèçâîäèòåëè.
-function FindVolumeInfo (const dataFileName: TSFSString; onlyPerm: Boolean=false): Integer;
+function FindVolumeInfo (const dataFileName: AnsiString; onlyPerm: Boolean=false): Integer;
 var
   f: Integer;
   vi: TVolumeInfo;
@@ -599,7 +595,7 @@ end;
 
 
 // adds '/' too
-function normalizePath (fn: string): string;
+function normalizePath (fn: AnsiString): AnsiString;
 var
   i: Integer;
 begin
@@ -625,7 +621,7 @@ begin
   if (length(result) > 0) and (result[length(result)] <> '/') then result := result+'/';
 end;
 
-function SFSReplacePathDelims (const s: TSFSString; newDelim: TSFSChar): TSFSString;
+function SFSReplacePathDelims (const s: AnsiString; newDelim: Char): AnsiString;
 var
   f: Integer;
 begin
@@ -640,9 +636,9 @@ begin
   end;
 end;
 
-function SFSGetLastVirtualName (const fn: TSFSString): string;
+function SFSGetLastVirtualName (const fn: AnsiString): AnsiString;
 var
-  rest, tmp: string;
+  rest, tmp: AnsiString;
   f: Integer;
 begin
   rest := fn;
@@ -661,7 +657,7 @@ var
   used: Boolean; // ôëàæîê çàþçàíîñòè ïîòîêà êåì-òî åù¸
 begin
   if fFactory <> nil then fFactory.Recycle(fVolume);
-  if fVolume <> nil then used := (fVolume.fRC <> 0) else used := false;
+  used := false;
   fVolume := nil;
   fFactory := nil;
   fPackName := '';
@@ -740,10 +736,9 @@ end;
 
 
 { TSFSVolume }
-constructor TSFSVolume.Create (const pFileName: TSFSString; pSt: TStream);
+constructor TSFSVolume.Create (const pFileName: AnsiString; pSt: TStream);
 begin
   inherited Create();
-  fRC := 0;
   fFileStream := pSt;
   fFileName := pFileName;
   fFiles := TObjectList.Create(true);
@@ -757,7 +752,7 @@ procedure TSFSVolume.DoDirectoryRead ();
 var
   f, c: Integer;
   sfi: TSFSFileInfo;
-  tmp: TSFSString;
+  tmp: AnsiString;
 begin
   fFileName := ExpandFileName(SFSReplacePathDelims(fFileName, '/'));
   ReadDirectory();
@@ -796,11 +791,10 @@ end;
 
 procedure TSFSVolume.Clear ();
 begin
-  fRC := 0; //FIXME
   fFiles.Clear();
 end;
 
-function TSFSVolume.FindFile (const fPath, fName: TSFSString): Integer;
+function TSFSVolume.FindFile (const fPath, fName: AnsiString): Integer;
 begin
   if fFiles = nil then result := -1
   else
@@ -834,9 +828,9 @@ begin
   end;
 end;
 
-function TSFSVolume.OpenFileEx (const fName: TSFSString): TStream;
+function TSFSVolume.OpenFileEx (const fName: AnsiString): TStream;
 var
-  fp, fn: TSFSString;
+  fp, fn: AnsiString;
   f, ls: Integer;
 begin
   fp := fName;
@@ -876,7 +870,6 @@ var
 begin
   f := FindVolumeInfoByVolumeInstance(fVolume);
   ASSERT(f <> -1);
-  if fVolume <> nil then Dec(fVolume.fRC);
   Dec(TVolumeInfo(volumes[f]).fOpenedFilesCount);
   // óáü¸ì çàïèñü, åñëè îíà âðåìåííàÿ, è â íåé íåò áîëüøå íè÷åãî îòêðûòîãî
   if (gcdisabled = 0) and not TVolumeInfo(volumes[f]).fPermanent and (TVolumeInfo(volumes[f]).fOpenedFilesCount < 1) then
@@ -927,7 +920,7 @@ begin
 end;
 
 
-function SFSAddDataFileEx (dataFileName: TSFSString; ds: TStream; top, permanent: Integer): Integer;
+function SFSAddDataFileEx (dataFileName: AnsiString; ds: TStream; top, permanent: Integer): Integer;
 // dataFileName ìîæåò èìåòü ïðåôèêñ òèïà "zip:" (ñì. âûøå: IsMyPrefix).
 // ìîæåò âûêèíóòü èñêëþ÷åíèå!
 // top:
@@ -948,8 +941,8 @@ var
   vi: TVolumeInfo;
   f: Integer;
   st, st1: TStream;
-  pfx: TSFSString;
-  fn, vfn, tmp: TSFSString;
+  pfx: AnsiString;
+  fn, vfn, tmp: AnsiString;
 begin
   f := Pos('::', dataFileName);
   if f <> 0 then
@@ -1058,7 +1051,7 @@ begin
   vi.fOpenedFilesCount := 0;
 end;
 
-function SFSAddSubDataFile (const virtualName: TSFSString; ds: TStream; top: Boolean=false): Boolean;
+function SFSAddSubDataFile (const virtualName: AnsiString; ds: TStream; top: Boolean=false): Boolean;
 var
   tv: Integer;
 begin
@@ -1072,7 +1065,7 @@ begin
   end;
 end;
 
-function SFSAddDataFile (const dataFileName: TSFSString; top: Boolean=false): Boolean;
+function SFSAddDataFile (const dataFileName: AnsiString; top: Boolean=false): Boolean;
 var
   tv: Integer;
 begin
@@ -1085,7 +1078,7 @@ begin
   end;
 end;
 
-function SFSAddDataFileTemp (const dataFileName: TSFSString; top: Boolean=false): Boolean;
+function SFSAddDataFileTemp (const dataFileName: AnsiString; top: Boolean=false): Boolean;
 var
   tv: Integer;
 begin
@@ -1100,10 +1093,10 @@ end;
 
 
 
-function SFSExpandDirName (const s: TSFSString): TSFSString;
+function SFSExpandDirName (const s: AnsiString): AnsiString;
 var
   f, e: Integer;
-  es: TSFSString;
+  es: AnsiString;
 begin
   f := 1; result := s;
   while f < Length(result) do
@@ -1128,9 +1121,9 @@ begin
   end;
 end;
 
-function SFSFileOpenEx (const fName: TSFSString): TStream;
+function SFSFileOpenEx (const fName: AnsiString): TStream;
 var
-  dataFileName, fn: TSFSString;
+  dataFileName, fn: AnsiString;
   f: Integer;
   vi: TVolumeInfo;
   diskChecked: Boolean;
@@ -1139,7 +1132,7 @@ var
   function CheckDisk (): TStream;
   // ïðîâåðèì, åñòü ëè ôàëî fn ãäå-òî íà äèñêàõ.
   var
-    dfn, dirs, cdir: TSFSString;
+    dfn, dirs, cdir: AnsiString;
     f: Integer;
   begin
     result := nil;
@@ -1230,7 +1223,7 @@ begin
   if result = nil then raise ESFSError.Create('file not found: "'+fName+'"');
 end;
 
-function SFSFileOpen (const fName: TSFSString): TStream;
+function SFSFileOpen (const fName: AnsiString): TStream;
 begin
   try
     result := SFSFileOpenEx(fName);
@@ -1239,7 +1232,7 @@ begin
   end;
 end;
 
-function SFSFileList (const dataFileName: TSFSString): TSFSFileList;
+function SFSFileList (const dataFileName: AnsiString): TSFSFileList;
 var
   f: Integer;
   vi: TVolumeInfo;
@@ -1256,7 +1249,6 @@ begin
 
   try
     result := TSFSFileList.Create(vi.fVolume);
-    Inc(vi.fVolume.fRC);
   except
     if (gcdisabled = 0) and not vi.fPermanent and (vi.fOpenedFilesCount < 1) then volumes[f] := nil;
   end;
diff --git a/src/sfs/sfsMemFS.pas b/src/sfs/sfsMemFS.pas
deleted file mode 100644
index 627ca78..0000000
--- a/src/sfs/sfsMemFS.pas
+++ /dev/null
@@ -1,247 +0,0 @@
-// Streaming R/O Virtual File System v0.2.0
-// Copyright (C) XL A.S. Ketmar.  All rights reserved
-// See the file aplicense.txt for conditions of use.
-//
-// "memory group". reads the whole pack in memory (and decompress it if
-// necessary). memory image has only one file named "<body>".
-//
-// now understands:
-//   slh!: DOS Allegro "slh!"
-//   mem : raw file (no processing, just read)
-//     as a side effect this gives us an opportunity to read enclosed packs
-//     from the packs which aren't supporting backseeking (such as zips).
-//
-{.$DEFINE SFS_MSMFS}
-{$MODE DELPHI}
-{.$R-}
-unit sfsMemFS;
-
-interface
-
-{$IFDEF SFS_MSMFS}
-uses
-  SysUtils, Classes, Contnrs, sfs;
-
-
-type
-  TSFSMemVolumeType = (sfsmvNone, sfsmvRAW, sfsmvSLH);
-
-  TSFSMemoryVolume = class(TSFSVolume)
-  protected
-    fType: TSFSMemVolumeType;
-    fMemStream: TMemoryStream;
-
-    procedure RAWRead ();
-    procedure SLHRead ();
-
-    procedure ReadDirectory (); override;
-
-  public
-    function OpenFileByIndex (const index: Integer): TStream; override;
-  end;
-
-  TSFSMemoryVolumeFactory = class (TSFSVolumeFactory)
-  public
-    function IsMyVolumePrefix (const prefix: TSFSString): Boolean; override;
-    function Produce (const prefix, fileName: TSFSString; st: TStream): TSFSVolume; override;
-    procedure Recycle (vol: TSFSVolume); override;
-  end;
-{$ENDIF}
-
-
-implementation
-
-{$IFDEF SFS_MSMFS}
-uses
-  xstreams, utils;
-
-
-function SLHCheckMagic (st: TStream): Boolean;
-var
-  sign: packed array [0..3] of Char;
-begin
-  result := false;
-  st.ReadBuffer(sign[0], 4);
-  st.Seek(-4, soCurrent);
-  if sign <> 'slh!' then exit;
-  result := true;
-end;
-
-
-{ TSFSMemoryVolume }
-procedure TSFSMemoryVolume.RAWRead ();
-var
-  fi: TSFSFileInfo;
-begin
-  fMemStream.CopyFrom(fFileStream, 0); // voila %-)
-  fi := TSFSFileInfo.Create(self);
-  fi.fName := '<body>';
-  fi.fSize := fMemStream.Size;
-end;
-
-procedure TSFSMemoryVolume.SLHRead ();
-// unpack LZSS-packed file
-var
-  fi: TSFSFileInfo;
-  bufi, bufo: packed array of Byte;
-  iused, oused, rpos: Integer;
-  dict: packed array of Byte;
-  flags, dpos, pos, len: Word;
-  c: Integer;
-
-  function ReadCh (): Integer;
-  begin
-    if rpos >= iused then
-    begin
-      // int64!
-      if fFileStream.Size-fFileStream.Position > Length(bufi) then iused := Length(bufi)
-      else iused := fFileStream.Size-fFileStream.Position;
-      rpos := 0;
-      if iused > 0 then fFileStream.ReadBuffer(bufi[0], iused);
-    end;
-
-    if iused = 0 then result := -1
-    else begin result := bufi[rpos]; Inc(rpos); end;
-  end;
-
-  procedure WriteCh (c: Byte);
-  begin
-    if oused >= Length(bufo) then
-    begin
-      fMemStream.WriteBuffer(bufo[0], oused);
-      oused := 0;
-    end;
-    bufo[oused] := c; Inc(oused);
-    dict[dpos] := c; dpos := (dpos+1) and $FFF;
-  end;
-
-begin
-  fFileStream.Seek(4, soCurrent); // skip signature
-  SetLength(bufi, 65536); SetLength(bufo, 65536); SetLength(dict, 4096);
-  rpos := 0; iused := 0; oused := 0;
-  flags := 0; dpos := 4096-18;
-  repeat
-    if (flags and $FF00) = 0 then
-    begin
-      c := ReadCh(); if c = -1 then break;
-      flags := c or $FF00;
-    end;
-
-    if (flags and $01) <> 0 then
-    begin
-      // literal
-      c := ReadCh(); if c = -1 then break;
-      WriteCh(c);
-    end
-    else
-    begin
-      // "copy"
-      c := ReadCh(); if c = -1 then break;
-      pos := c;
-      c := ReadCh(); if c = -1 then break;
-      len := c;
-      pos := (pos and $FF) or ((len and $F0) shl 4); len := (len and $0F)+3;
-      while len > 0 do
-      begin
-        c := dict[pos]; pos := (pos+1) and $FFF; Dec(len);
-        WriteCh(c);
-      end;
-    end;
-    flags := flags shr 1;
-  until false;
-  if oused > 0 then fMemStream.WriteBuffer(bufo[0], oused);
-
-  fi := TSFSFileInfo.Create(self);
-  fi.fName := '<body>';
-  fi.fSize := fMemStream.Size;
-end;
-
-procedure TSFSMemoryVolume.ReadDirectory ();
-begin
-  if fMemStream = nil then fMemStream := TMemoryStream.Create()
-  else
-  begin
-    fMemStream.Position := 0; fMemStream.Size := 0;
-  end;
-
-  case fType of
-    sfsmvSLH: SLHRead();
-    sfsmvRAW: RAWRead();
-    else raise ESFSError.Create('invalid memory SFS');
-  end;
-
-  fMemStream.Position := 0;
-end;
-
-function TSFSMemoryVolume.OpenFileByIndex (const index: Integer): TStream;
-var
-  fs: TStream;
-begin
-  result := nil; fs := nil;
-  if fFiles = nil then exit;
-  if (index < 0) or (index >= fFiles.Count) or (fFiles[index] = nil) then exit;
-
-  try
-    fs := TSFSMemoryStreamRO.Create(fMemStream.Memory, fMemStream.Size);
-    if fFiles.Count = 1 then
-    begin
-      result := fs;
-    end
-    else
-    begin
-      try
-        result := TSFSPartialStream.Create(fs,
-          TSFSFileInfo(fFiles[index]).fOfs,
-          TSFSFileInfo(fFiles[index]).fSize, true);
-      except
-        FreeAndNil(fs);
-        raise;
-      end;
-    end;
-  except
-    result := nil;
-  end;
-end;
-
-
-{ TSFSMemoryVolumeFactory }
-function TSFSMemoryVolumeFactory.IsMyVolumePrefix (const prefix: TSFSString): Boolean;
-begin
-  result :=
-    StrEquCI1251(prefix, 'mem') or
-    StrEquCI1251(prefix, 'slh!');
-end;
-
-procedure TSFSMemoryVolumeFactory.Recycle (vol: TSFSVolume);
-begin
-  vol.Free();
-end;
-
-function TSFSMemoryVolumeFactory.Produce (const prefix, fileName: TSFSString; st: TStream): TSFSVolume;
-var
-  vt: TSFSMemVolumeType;
-begin
-  if (prefix <> 'mem') and SLHCheckMagic(st) then vt := sfsmvSLH
-  else if prefix <> '' then vt := sfsmvRAW
-  else vt := sfsmvNone;
-
-  result := TSFSMemoryVolume.Create(fileName, st);
-  TSFSMemoryVolume(result).fType := vt;
-  try
-    result.DoDirectoryRead();
-  except
-    FreeAndNil(result);
-    raise;
-  end;
-end;
-
-
-var
-  memf: TSFSMemoryVolumeFactory;
-initialization
-  memf := TSFSMemoryVolumeFactory.Create();
-  SFSRegisterVolumeFactory(memf);
-//finalization
-//  SFSUnregisterVolumeFactory(memf);
-{$ENDIF}
-end.
diff --git a/src/sfs/sfsPlainFS.pas b/src/sfs/sfsPlainFS.pas
index b658388..e0b2bd0 100644
--- a/src/sfs/sfsPlainFS.pas
+++ b/src/sfs/sfsPlainFS.pas
@@ -3,24 +3,11 @@
 // See the file aplicense.txt for conditions of use.
 //
 // simple grouping files w/o packing:
-//   wad, doom       : DooM .WAD (IWAD, PWAD)
-//   pak, quake      : Quake I/II .PAK (PACK)
-//   grp, duke3d     : Duke3D .GRP (KenSilverman)
-//   spe, spec, abuse: Abuse .SPE (SPEC1.0)
-//   wad2            : Quake .WAD (WAD2)
-//   allegro         : DOS Allegro (slh.ALL.; ALL.)
-//   dune2 pak       : alas, no signature %-(
-//   M.A.X. res      : RES0
-//   sin             : SiN .SIN (SPAK)
+//   Quake I/II .PAK (PACK)
+//   SiN .SIN (SPAK)
 //
-{.$DEFINE SFS_PLAIN_FS_ALTERNATIVE_SPEC}
-  // define this and the first byte of each file in .SPE will contain
-  // file type.
-  // undefine this and file type will be directory name.
-{.$DEFINE SFS_PLAIN_FS_DEBUG_ALLEGRO}
-{.$DEFINE SFS_PLAINFS_FULL}
-{$MODE DELPHI}
-{.$R-}
+{$MODE OBJFPC}
+{$R+}
 unit sfsPlainFS;
 
 interface
@@ -30,37 +17,12 @@ uses
 
 
 type
-  TSFSPlainVolumeType =
-    (sfspvNone,
-     sfspvPAK,
-     sfspvSIN
-     {$IFDEF SFS_PLAINFS_FULL}
-     ,sfspvWAD,
-     sfspvGRP,
-     sfspvSPE,
-     sfspvWAD2,
-     sfspvALL,
-     sfspvDune2,
-     sfspvMAX
-     {$ENDIF}
-     );
+  TSFSPlainVolumeType = (sfspvNone, sfspvPAK, sfspvSIN);
 
   TSFSPlainVolume = class (TSFSVolume)
   protected
     fType: TSFSPlainVolumeType;
 
-    procedure PAKReadDirectory ();
-    procedure SINReadDirectory ();
-    {$IFDEF SFS_PLAINFS_FULL}
-    procedure WADReadDirectory ();
-    procedure GRPReadDirectory ();
-    procedure SPEReadDirectory ();
-    procedure WAD2ReadDirectory ();
-    procedure ALLReadDirectory ();
-    procedure Dune2ReadDirectory ();
-    procedure MAXReadDirectory ();
-    {$ENDIF}
-
     procedure ReadDirectory (); override;
 
   public
@@ -69,646 +31,58 @@ type
 
   TSFSPlainVolumeFactory = class (TSFSVolumeFactory)
   public
-    function IsMyVolumePrefix (const prefix: TSFSString): Boolean; override;
-    function Produce (const prefix, fileName: TSFSString; st: TStream): TSFSVolume; override;
+    function IsMyVolumePrefix (const prefix: AnsiString): Boolean; override;
+    function Produce (const prefix, fileName: AnsiString; st: TStream): TSFSVolume; override;
     procedure Recycle (vol: TSFSVolume); override;
   end;
 
 
-
 implementation
 
 uses
   xstreams, utils;
 
 
-type
-  TSFSExtFileInfo = class (TSFSFileInfo)
-  public
-    fVBuf: packed array of Byte;
-    fLink: TSFSString;
-  end;
-
-{$IFDEF SFS_PLAINFS_FULL}
-  TAllegroProperty = class
-    name: TSFSString;
-    ofs: Int64;
-    size: Integer;
-  end;
-{$ENDIF}
-
-
-function ReadMD (st: TStream): Integer;
-// read dword in big-endian format. portable.
-var
-  buf: packed array [0..3] of Byte;
-begin
-  st.ReadBuffer(buf[0], 4);
-  result := (buf[0] shl 24) or (buf[1] shl 16) or (buf[2] shl 8) or buf[3];
-end;
-
-{$IFDEF SFS_PLAINFS_FULL}
-function WADCheckMagic (st: TStream): Boolean;
-var
-  sign: packed array [0..3] of Char;
-  fcnt, dofs: Integer;
-begin
-  result := false;
-  st.ReadBuffer(sign[0], 4);
-  st.ReadBuffer(fcnt, 4); st.ReadBuffer(dofs, 4);
-  st.Seek(-12, soCurrent);
-  if (sign <> 'IWAD') and (sign <> 'PWAD') then exit;
-  if (dofs < 0) or (dofs > st.Size) or (fcnt < 0) or
-     (dofs+fcnt*16 > st.Size) then exit;
-  result := true;
-end;
-{$ENDIF}
-
-function PAKCheckMagic (st: TStream): Boolean;
-var
-  sign: packed array [0..3] of Char;
-  dsize, dofs: Integer;
-begin
-  result := false;
-  st.ReadBuffer(sign[0], 4);
-  st.ReadBuffer(dofs, 4); st.ReadBuffer(dsize, 4);
-  st.Seek(-12, soCurrent);
-  if sign <> 'PACK' then exit;
-  if (dsize < 0) or (dofs < 0) or (dofs > st.Size) or (dofs+dsize > st.Size) or
-     (dsize mod 64 <> 0) then exit;
-  result := true;
-end;
-
-function SINCheckMagic (st: TStream): Boolean;
-var
-  sign: packed array [0..3] of Char;
-  dsize, dofs: Integer;
-begin
-  result := false;
-  st.ReadBuffer(sign[0], 4);
-  st.ReadBuffer(dofs, 4); st.ReadBuffer(dsize, 4);
-  st.Seek(-12, soCurrent);
-  if sign <> 'SPAK' then exit;
-  if (dsize < 0) or (dofs < 0) or (dofs > st.Size) or (dofs+dsize > st.Size) or
-     (dsize mod 64 <> 0) then exit;
-  result := true;
-end;
-
-{$IFDEF SFS_PLAINFS_FULL}
-function GRPCheckMagic (st: TStream): Boolean;
-var
-  sign: packed array [0..11] of Char;
-  fcnt: Integer;
-begin
-  result := false;
-  st.ReadBuffer(sign[0], 12);
-  st.ReadBuffer(fcnt, 4);
-  st.Seek(-16, soCurrent);
-  if sign <> 'KenSilverman' then exit;
-  if (fcnt < 0) or (fcnt*16 > st.Size-16) then exit;
-  result := true;
-end;
-
-function SPECheckMagic (st: TStream): Boolean;
-var
-  sign: packed array [0..6] of Char;
-  b: Byte;
-  fcnt: Integer;
-begin
-  result := false;
-  st.ReadBuffer(sign[0], 7); st.ReadBuffer(b, 1);
-  st.ReadBuffer(fcnt, 4);
-  st.Seek(-12, soCurrent);
-  if (sign <> 'SPEC1.0') or (b <> 0) or (fcnt < 0) then exit;
-  result := true;
-end;
-
-function WAD2CheckMagic (st: TStream): Boolean;
-var
-  sign: packed array [0..3] of Char;
-  fcnt, dofs: Integer;
-begin
-  result := false;
-  st.ReadBuffer(sign[0], 4);
-  st.ReadBuffer(fcnt, 4); st.ReadBuffer(dofs, 4);
-  st.Seek(-12, soCurrent);
-  if sign <> 'WAD2' then exit;
-  if (dofs < 0) or (dofs > st.Size) or (fcnt < 0) or
-     (dofs+fcnt*32 > st.Size) then exit;
-  result := true;
-end;
-
-function ALLCheckMagic (st: TStream): Boolean;
-var
-  sign0, sign1: packed array [0..3] of Char;
-begin
-  result := false;
-  st.ReadBuffer(sign0[0], 4);
-  st.ReadBuffer(sign1[0], 4);
-  st.Seek(-8, soCurrent);
-  if sign0 = 'slh.' then
-  begin
-    if sign1 <> 'ALL.' then exit;
-  end else if sign0 <> 'ALL.' then exit;
-  result := true;
-end;
-
-function Dune2CheckMagic (st: TStream): Boolean;
-var
-  cpos, np, f: Integer;
-begin
-  cpos := st.Position;
-  st.ReadBuffer(np, 4);
-  st.Position := np-4;
-  st.ReadBuffer(f, 4);
-  st.Position := cpos;
-  result := (f = 0);
-end;
-
-function MAXCheckMagic (st: TStream): Boolean;
-var
-  sign: packed array [0..3] of Char;
-  fcnt, dofs: Integer;
-begin
-  result := false;
-  st.ReadBuffer(sign[0], 4);
-  st.ReadBuffer(dofs, 4); st.ReadBuffer(fcnt, 4);
-  st.Seek(-12, soCurrent);
-  if sign <> 'RES0' then exit;
-  if (dofs < 0) or (dofs > st.Size) or (fcnt < 0) or
-     (dofs+fcnt > st.Size) then exit;
-  result := true;
-end;
-{$ENDIF}
-
-
 { TSFSPlainVolume }
-{$IFDEF SFS_PLAINFS_FULL}
-procedure TSFSPlainVolume.WADReadDirectory ();
-var
-  fcnt: LongWord;
-  dofs: LongWord;
-  fi: TSFSFileInfo;
-  name: packed array [0..9] of Char;
-begin
-  fFileStream.Seek(4, soCurrent); // skip signature
-  fFileStream.ReadBuffer(fcnt, 4);
-  fFileStream.ReadBuffer(dofs, 4);
-  fFileStream.Position := dofs;
-  while fcnt <> 0 do
-  begin
-    fi := TSFSFileInfo.Create(self);
-    fFileStream.ReadBuffer(fi.fOfs, 4);
-    fFileStream.ReadBuffer(fi.fSize, 4);
-    FillChar(name[0], Length(name), 0);
-    fFileStream.ReadBuffer(name[0], 8);
-    fi.fName := PChar(@name[0]);
-    Dec(fcnt);
-  end;
-end;
-{$ENDIF}
-
-procedure TSFSPlainVolume.PAKReadDirectory ();
-var
-  dsize, dofs: LongWord;
-  fi: TSFSFileInfo;
-  name: packed array [0..56] of Char;
-begin
-  fFileStream.Seek(4, soCurrent); // skip signature
-  fFileStream.ReadBuffer(dofs, 4);
-  fFileStream.ReadBuffer(dsize, 4);
-  fFileStream.Position := dofs;
-  while dsize >= 64 do
-  begin
-    fi := TSFSFileInfo.Create(self);
-    FillChar(name[0], Length(name), 0);
-    fFileStream.ReadBuffer(name[0], 56);
-    fi.fName := PChar(@name[0]);
-    fFileStream.ReadBuffer(fi.fOfs, 4);
-    fFileStream.ReadBuffer(fi.fSize, 4);
-    Dec(dsize, 64);
-  end;
-end;
-
-procedure TSFSPlainVolume.SINReadDirectory ();
+procedure TSFSPlainVolume.ReadDirectory ();
 var
-  dsize, dofs: LongWord;
+  dsize, dofs, esz: LongWord;
   fi: TSFSFileInfo;
   name: packed array [0..120] of Char;
 begin
+  if (fType <> sfspvPAK) and (fType <> sfspvSIN) then raise ESFSError.Create('invalid archive');
   fFileStream.Seek(4, soCurrent); // skip signature
   fFileStream.ReadBuffer(dofs, 4);
   fFileStream.ReadBuffer(dsize, 4);
   fFileStream.Position := dofs;
-  while dsize >= 128 do
-  begin
-    fi := TSFSFileInfo.Create(self);
-    FillChar(name[0], Length(name), 0);
-    fFileStream.ReadBuffer(name[0], 120);
-    fi.fName := PChar(@name[0]);
-    fFileStream.ReadBuffer(fi.fOfs, 4);
-    fFileStream.ReadBuffer(fi.fSize, 4);
-    Dec(dsize, 128);
-  end;
-end;
-
-{$IFDEF SFS_PLAINFS_FULL}
-procedure TSFSPlainVolume.GRPReadDirectory ();
-var
-  fcnt: LongWord;
-  fi: TSFSFileInfo;
-  name: packed array [0..12] of Char;
-  ofs: Int64;
-begin
-  fFileStream.Seek(12, soCurrent); // skip signature
-  fFileStream.ReadBuffer(fcnt, 4);
-  ofs := fFileStream.Position+fcnt*16;
-  while fcnt <> 0 do
-  begin
-    fi := TSFSFileInfo.Create(self);
-    fi.fOfs := ofs;
-    FillChar(name[0], Length(name), 0);
-    fFileStream.ReadBuffer(name[0], 12);
-    fi.fName := PChar(@name[0]);
-    fFileStream.ReadBuffer(fi.fSize, 4);
-    Inc(ofs, fi.fSize);
-    Dec(fcnt);
-  end;
-end;
-
-procedure TSFSPlainVolume.SPEReadDirectory ();
-var
-  fcnt: Word;
-  fi: TSFSExtFileInfo;
-  {$IFNDEF SFS_PLAIN_FS_ALTERNATIVE_SPEC}
-  pp: TSFSString;
-  {$ENDIF}
-  name: ShortString;
-  f, c: Integer;
-  b: Byte;
-  wasUnfixedLink: Boolean;
-begin
-  fFileStream.Seek(8, soCurrent); // skip signature
-  fFileStream.ReadBuffer(fcnt, 2);
-  while fcnt <> 0 do
-  begin
-    fi := TSFSExtFileInfo.Create(self);
-   {$IFDEF SFS_PLAIN_FS_ALTERNATIVE_SPEC}
-    SetLength(fi.fVBuf, 1); fFileStream.ReadBuffer(fi.fVBuf[0], 1);
-   {$ELSE}
-     SetLength(fi.fVBuf, 0);
-    fFileStream.ReadBuffer(b, 1);
-    pp := IntToHex(b, 2)+'/';
-   {$ENDIF}
-    fFileStream.ReadBuffer(name[0], 1);
-    if name[0] <> #0 then fFileStream.ReadBuffer(name[1], Length(name));
-    f := 1; while (f <= ord(name[0])) and (name[f] <> #0) do Inc(f); name[0] := chr(f-1);
-    fi.fName := SFSReplacePathDelims(name, '/');
-    if fi.fName = '' then fi.fName := 'untitled_file';
-    if fi.fName[1] = '/' then Delete(fi.fName, 1, 1);
-   {$IFNDEF SFS_PLAIN_FS_ALTERNATIVE_SPEC}
-    fi.fName := pp+fi.fName;
-   {$ENDIF}
-    fFileStream.ReadBuffer(b, 1);
-    if (b and $01) <> 0 then
-    begin
-      // link
-      fFileStream.ReadBuffer(name[0], 1);
-      if name[0] <> #0 then fFileStream.ReadBuffer(name[1], Length(name));
-      f := 1; while (f <= ord(name[0])) and (name[f] <> #0) do Inc(f); name[0] := chr(f-1);
-      if name[0] = #0 then name := #0;
-      fi.fLink := name;
-    end
-    else
-    begin
-      fi.fLink := '';
-      fFileStream.ReadBuffer(fi.fSize, 4);
-     {$IFDEF SFS_PLAIN_FS_ALTERNATIVE_SPEC}
-      Inc(fi.fSize); // plus type byte
-     {$ENDIF}
-      fFileStream.ReadBuffer(fi.fOfs, 4);
-    end;
-    Dec(fcnt);
-  end;
-
-  // now fixup links
-  // nobody uses this shit, but it was documented by JC. %-)
-  // i even allow links to links! %-)
-  wasUnfixedLink := true;
-  while wasUnfixedLink do
-  begin
-    f := 0; wasUnfixedLink := false;
-    while f < fFiles.Count do
-    begin
-      fi := TSFSExtFileInfo(fFiles[f]); Inc(f);
-      if (fi = nil) or (fi.fLink = '') then continue;
-      c := 0;
-      while c < fFiles.Count do
-      begin
-        if c <> f then
-        begin
-          // link can't be linked to itself
-          if StrEquCI1251(TSFSExtFileInfo(fFiles[c]).fName, fi.fLink) then break;
-        end;
-        Inc(c);
-      end;
-      if c < fFiles.Count then
-      begin
-        if TSFSExtFileInfo(fFiles[c]).fLink <> '' then wasUnfixedLink := true
-        else
-        begin
-          TSFSExtFileInfo(fFiles[c]).fOfs := fi.fOfs;
-          TSFSExtFileInfo(fFiles[c]).fSize := fi.fSize;
-          TSFSExtFileInfo(fFiles[c]).fLink := '';
-        end;
-      end
-      else begin Dec(f); fFiles.Delete(f); end; // invalid link
-    end;
-  end;
-end;
-
-procedure TSFSPlainVolume.WAD2ReadDirectory ();
-var
-  fcnt, dofs: LongWord;
-  fi: TSFSFileInfo;
-  name: packed array [0..16] of Char;
-  f, c: Integer;
-begin
-  fFileStream.Seek(4, soCurrent); // skip signature
-  fFileStream.ReadBuffer(fcnt, 4);
-  fFileStream.ReadBuffer(dofs, 4);
-  fFileStream.Position := dofs;
-  while fcnt <> 0 do
+  if fType = sfspvPAK then esz := 64 else esz := 128;
+  while dsize >= esz do
   begin
     fi := TSFSFileInfo.Create(self);
-    fFileStream.ReadBuffer(fi.fOfs, 4);
-    fFileStream.ReadBuffer(fi.fSize, 4);
-    fFileStream.ReadBuffer(f, 4);
-    fFileStream.ReadBuffer(c, 4);
-    FillChar(name[0], Length(name), 0);
-    fFileStream.ReadBuffer(name[0], 16);
+    FillChar(name[0], length(name), 0);
+    fFileStream.ReadBuffer(name[0], esz-8);
     fi.fName := PChar(@name[0]);
-    Dec(fcnt);
-  end;
-end;
-
-procedure TSFSPlainVolume.ALLReadDirectory ();
-var
-  fcnt: Integer;
-  fi: TSFSFileInfo;
-  sign: packed array [0..3] of Char;
-  nameList: TStringList;
-  propList: TObjectList;
-  name: ShortString;
-  f, c: Integer;
-  prp: TAllegroProperty;
-begin
-  nameList := TStringList.Create(); propList := nil;
-  try
-    propList := TObjectList.Create(true);
-    fFileStream.ReadBuffer(sign[0], 4);
-    if sign[0] = 's' then fFileStream.ReadBuffer(sign[0], 4);
-    // signature skipped
-    fcnt := ReadMD(fFileStream);
-    while fcnt > 0 do
-    begin
-      // collect properties
-      nameList.Clear(); propList.Clear();
-      repeat
-        fFileStream.ReadBuffer(sign[0], 4);
-        if sign <> 'prop' then break;
-        fFileStream.ReadBuffer(sign[0], 4);
-        f := ReadMD(fFileStream); // size
-        if f < 0 then
-        begin
-         {$IFDEF SFS_PLAIN_FS_DEBUG_ALLEGRO}
-          WriteLn(ErrOutput, 'ALLEGRO: invalid property length at $', IntToHex(fFileStream.Position-8, 8));
-         {$ENDIF}
-          raise ESFSError.Create('invalid ALLEGRO file');
-        end;
-        if sign = 'NAME' then
-        begin
-          if f > 255 then c := 255 else c := f;
-          FillChar(name, SizeOf(name), 0);
-          fFileStream.ReadBuffer(name[1], c); name[0] := chr(c);
-          Dec(f, c);
-          c := 1; while (c <= ord(name[0])) and (name[c] <> #0) do Inc(c); name[0] := chr(c-1);
-          nameList.Add(name);
-        end
-        else
-        begin
-          prp := TAllegroProperty.Create();
-          Move(sign[0], name[1], 4); name[0] := #4;
-          c := 1; while (c <= ord(name[0])) and (name[c] <> #0) do Inc(c); name[0] := chr(c-1);
-          prp.name := sign;
-          prp.ofs := fFileStream.Position;
-          prp.size := f;
-          propList.Add(prp);
-        end;
-        fFileStream.Seek(f, soCurrent);
-      until false;
-      if nameList.Count = 0 then nameList.Add('untitled_file');
-
-      Move(sign[0], name[1], 4); name[5] := #0;
-      f := 1; while (f <= 4) and (name[f] <> #0) do Inc(f);
-      while (f > 0) and (name[f] <= ' ') do Dec(f);
-      name[0] := chr(f);
-
-      // read size
-      f := ReadMD(fFileStream);
-      c := ReadMD(fFileStream);
-      if f <> c then
-      begin
-       {$IFDEF SFS_PLAIN_FS_DEBUG_ALLEGRO}
-        WriteLn(ErrOutput, 'ALLEGRO: probably a packed data at $', IntToHex(fFileStream.Position-8, 8));
-       {$ENDIF}
-        raise ESFSError.Create('invalid ALLEGRO file');
-      end;
-
-      // add files
-      while nameList.Count > 0 do
-      begin
-        fi := TSFSFileInfo.Create(self);
-        fi.fName := nameList[0];
-        fi.fPath := name;
-        fi.fSize := c;
-        fi.fOfs := fFileStream.Position;
-        // add properties
-        for f := 0 to propList.Count-1 do
-        begin
-          prp := TAllegroProperty(propList[f]);
-          fi := TSFSFileInfo.Create(self);
-          fi.fName := prp.name;
-          fi.fPath := name+'.props/'+nameList[0];
-          fi.fSize := prp.size;
-          fi.fOfs := prp.ofs;
-        end;
-        nameList.Delete(0);
-      end;
-      fFileStream.Seek(c, soCurrent);
-      Dec(fcnt);
-    end;
-   {$IFDEF SFS_PLAIN_FS_DEBUG_ALLEGRO}
-    WriteLn(ErrOutput, 'ALLEGRO: ok');
-   {$ENDIF}
-  finally
-    propList.Free();
-    nameList.Free();
-  end;
-end;
-
-procedure TSFSPlainVolume.Dune2ReadDirectory ();
-var
-  ofs: LongWord;
-  fi: TSFSFileInfo;
-  name: string[255];
-  ch: Char;
-begin
-  repeat
-    fFileStream.ReadBuffer(ofs, 4);
-    if ofs = 0 then break;
-    name[0] := #0;
-    fFileStream.ReadBuffer(ch, 1);
-    while ch <> #0 do
-    begin
-      if name[0] <> #255 then
-      begin
-        Inc(name[0]); name[ord(name[0])] := ch;
-      end;
-      fFileStream.ReadBuffer(ch, 1);
-    end;
-    if fFiles.Count > 0 then
-    begin
-      fi := TSFSFileInfo(fFiles[fFiles.Count-1]);
-      fi.fSize := ofs-fi.fOfs;
-    end;
-    fi := TSFSFileInfo.Create(self);
-    fi.fOfs := ofs;
-    fi.fSize := 0;
-    fi.fName := name;
-  until false;
-  if fFiles.Count > 0 then
-  begin
-    fi := TSFSFileInfo(fFiles[fFiles.Count-1]);
-    fi.fSize := fFileStream.Size-fi.fOfs;
-  end;
-end;
-
-procedure TSFSPlainVolume.MAXReadDirectory ();
-var
-  fcnt: LongInt;
-  dofs: LongWord;
-  fi: TSFSFileInfo;
-  name: packed array [0..9] of Char;
-begin
-  fFileStream.Seek(4, soCurrent); // skip signature
-  fFileStream.ReadBuffer(dofs, 4);
-  fFileStream.ReadBuffer(fcnt, 4);
-  fFileStream.Position := dofs;
-  while fcnt >= 16 do
-  begin
-    fi := TSFSFileInfo.Create(self);
-    FillChar(name[0], Length(name), 0);
-    fFileStream.ReadBuffer(name[0], 8);
     fFileStream.ReadBuffer(fi.fOfs, 4);
     fFileStream.ReadBuffer(fi.fSize, 4);
-    fi.fName := PChar(@name[0]);
-    Dec(fcnt, 16);
-  end;
-end;
-{$ENDIF}
-
-procedure TSFSPlainVolume.ReadDirectory ();
-begin
-  case fType of
-    sfspvPAK: PAKReadDirectory();
-    sfspvSIN: SINReadDirectory();
-    {$IFDEF SFS_PLAINFS_FULL}
-    sfspvWAD: WADReadDirectory();
-    sfspvGRP: GRPReadDirectory();
-    sfspvSPE: SPEReadDirectory();
-    sfspvWAD2: WAD2ReadDirectory();
-    sfspvALL: ALLReadDirectory();
-    sfspvDune2: Dune2ReadDirectory();
-    sfspvMAX: MAXReadDirectory();
-    {$ENDIF}
-    else raise ESFSError.Create('invalid plain SFS');
+    Dec(dsize, esz);
   end;
 end;
 
 function TSFSPlainVolume.OpenFileByIndex (const index: Integer): TStream;
-var
-  fs: TStream;
-  kill: Boolean;
 begin
-  result := nil; fs := nil;
+  result := nil;
   if fFiles = nil then exit;
   if (index < 0) or (index >= fFiles.Count) or (fFiles[index] = nil) then exit;
-  if not (fFiles[index] is TSFSExtFileInfo) or
-     (Length(TSFSExtFileInfo(fFiles[index]).fVBuf) < 1) then
-  begin
-    kill := false;
-    try
-      try
-        fs := TFileStream.Create(fFileName, fmOpenRead or {fmShareDenyWrite}fmShareDenyNone);
-        kill := true;
-      except
-        fs := fFileStream;
-      end;
-      result := TSFSPartialStream.Create(fs,
-        TSFSFileInfo(fFiles[index]).fOfs,
-        TSFSFileInfo(fFiles[index]).fSize, kill);
-    except
-      if kill then FreeAndNil(fs);
-      result := nil;
-    end;
-  end
-  else
-  begin
-    kill := false;
-    try
-      try
-        fs := TFileStream.Create(fFileName, fmOpenRead or {fmShareDenyWrite}fmShareDenyNone);
-        kill := true;
-      except
-        fs := fFileStream;
-      end;
-      result := TSFSPartialStream.Create(fs,
-        TSFSExtFileInfo(fFiles[index]).fOfs,
-        TSFSExtFileInfo(fFiles[index]).fSize-Length(TSFSExtFileInfo(fFiles[index]).fVBuf),
-        kill,
-        @(TSFSExtFileInfo(fFiles[index]).fVBuf[0]),
-        Length(TSFSExtFileInfo(fFiles[index]).fVBuf));
-    except
-      if kill then FreeAndNil(fs);
-      result := nil;
-    end;
-  end;
+  result := TSFSPartialStream.Create(fFileStream, TSFSFileInfo(fFiles[index]).fOfs, TSFSFileInfo(fFiles[index]).fSize, false);
 end;
 
 
 { TSFSPlainVolumeFactory }
-function TSFSPlainVolumeFactory.IsMyVolumePrefix (const prefix: TSFSString): Boolean;
+function TSFSPlainVolumeFactory.IsMyVolumePrefix (const prefix: AnsiString): Boolean;
 begin
   result :=
     StrEquCI1251(prefix, 'pak') or
-    StrEquCI1251(prefix, 'sin') or
-    StrEquCI1251(prefix, 'quake')
-    {$IFDEF SFS_PLAINFS_FULL}
-    or
-    StrEquCI1251(prefix, 'wad') or // sorry
-    StrEquCI1251(prefix, 'wad2') or
-    StrEquCI1251(prefix, 'grp') or
-    StrEquCI1251(prefix, 'spe') or
-    StrEquCI1251(prefix, 'spec') or
-    StrEquCI1251(prefix, 'doom') or
-    StrEquCI1251(prefix, 'duke3d') or
-    StrEquCI1251(prefix, 'abuse') or
-    StrEquCI1251(prefix, 'allegro') or
-    StrEquCI1251(prefix, 'dune2') or
-    StrEquCI1251(prefix, 'max')
-    {$ENDIF}
-    ;
+    StrEquCI1251(prefix, 'sin');
 end;
 
 procedure TSFSPlainVolumeFactory.Recycle (vol: TSFSVolume);
@@ -716,36 +90,38 @@ begin
   vol.Free();
 end;
 
-function TSFSPlainVolumeFactory.Produce (const prefix, fileName: TSFSString; st: TStream): TSFSVolume;
+function TSFSPlainVolumeFactory.Produce (const prefix, fileName: AnsiString; st: TStream): TSFSVolume;
 var
   vt: TSFSPlainVolumeType;
+  sign: packed array [0..3] of Char;
+  dsize, dofs: Integer;
 begin
+  result := nil;
   vt := sfspvNone;
-  if PAKCheckMagic(st) then vt := sfspvPAK
-  else if SINCheckMagic(st) then vt := sfspvSIN
-  {$IFDEF SFS_PLAINFS_FULL}
-  else if WADCheckMagic(st) then vt := sfspvWAD
-  else if GRPCheckMagic(st) then vt := sfspvGRP
-  else if SPECheckMagic(st) then vt := sfspvSPE
-  else if WAD2CheckMagic(st) then vt := sfspvWAD2
-  //else if ALLCheckMagic(st) then vt := sfspvALL
-  else if MAXCheckMagic(st) then vt := sfspvMAX
-  //else if Dune2CheckMagic(st) then vt := sfspvDune2 // this must be the last!
-  {$ENDIF}
-  ;
 
-  if vt <> sfspvNone then
+  st.ReadBuffer(sign[0], 4);
+  st.ReadBuffer(dofs, 4);
+  st.ReadBuffer(dsize, 4);
+  st.Seek(-12, soCurrent);
+  if sign = 'PACK' then
   begin
-    result := TSFSPlainVolume.Create(fileName, st);
-    TSFSPlainVolume(result).fType := vt;
-    try
-      result.DoDirectoryRead();
-    except
-      FreeAndNil(result);
-      raise;
-    end;
+    if (dsize < 0) or (dofs < 0) or (dofs > st.Size) or (dofs+dsize > st.Size) or (dsize mod 64 <> 0) then exit;
+    vt := sfspvPAK;
   end
-  else result := nil;
+  else if sign = 'SPAK' then
+  begin
+    if (dsize < 0) or (dofs < 0) or (dofs > st.Size) or (dofs+dsize > st.Size) or (dsize mod 64 <> 0) then exit;
+    vt := sfspvSIN;
+  end;
+
+  result := TSFSPlainVolume.Create(fileName, st);
+  TSFSPlainVolume(result).fType := vt;
+  try
+    result.DoDirectoryRead();
+  except
+    FreeAndNil(result);
+    raise;
+  end;
 end;
 
 
diff --git a/src/sfs/sfsZipFS.pas b/src/sfs/sfsZipFS.pas
index 7a1852a..892dd63 100644
--- a/src/sfs/sfsZipFS.pas
+++ b/src/sfs/sfsZipFS.pas
@@ -10,8 +10,8 @@
 //
 {.$DEFINE SFS_DEBUG_ZIPFS}
 {.$DEFINE SFS_ZIPFS_FULL}
-{$MODE DELPHI}
-{.$R-}
+{$MODE OBJFPC}
+{$R+}
 unit sfsZipFS;
 
 interface
@@ -51,8 +51,8 @@ type
 
   TSFSZipVolumeFactory = class (TSFSVolumeFactory)
   public
-    function IsMyVolumePrefix (const prefix: TSFSString): Boolean; override;
-    function Produce (const prefix, fileName: TSFSString; st: TStream): TSFSVolume; override;
+    function IsMyVolumePrefix (const prefix: AnsiString): Boolean; override;
+    function Produce (const prefix, fileName: AnsiString; st: TStream): TSFSVolume; override;
     procedure Recycle (vol: TSFSVolume); override;
   end;
 
@@ -604,7 +604,7 @@ end;
 
 
 { TSFSZipVolumeFactory }
-function TSFSZipVolumeFactory.IsMyVolumePrefix (const prefix: TSFSString): Boolean;
+function TSFSZipVolumeFactory.IsMyVolumePrefix (const prefix: AnsiString): Boolean;
 begin
   result :=
     StrEquCI1251(prefix, 'zip') or
@@ -623,7 +623,7 @@ begin
   vol.Free();
 end;
 
-function TSFSZipVolumeFactory.Produce (const prefix, fileName: TSFSString; st: TStream): TSFSVolume;
+function TSFSZipVolumeFactory.Produce (const prefix, fileName: AnsiString; st: TStream): TSFSVolume;
 var
   vt: TSFSZipVolumeType;
 begin
diff --git a/src/sfs/wadcvt.dpr b/src/sfs/wadcvt.dpr
index 1fa828a..34ffcfb 100644
--- a/src/sfs/wadcvt.dpr
+++ b/src/sfs/wadcvt.dpr
@@ -7,12 +7,11 @@ program __wadcvt__;
 uses
   SysUtils,
   Classes,
-  SDL2 in '../lib/sdl2/sdl2.pas',
-  utils in  '../shared/utils.pas',
+  utils in '../shared/utils.pas',
+  xstreams in '../shared/xstreams.pas',
   sfs,
   sfsPlainFS,
   sfsZipFS,
-  sfsMemFS,
   zipper;
 
 
diff --git a/src/shared/utils.pas b/src/shared/utils.pas
index 712923e..235dee4 100644
--- a/src/shared/utils.pas
+++ b/src/shared/utils.pas
@@ -3,6 +3,10 @@ unit utils;
 
 interface
 
+uses
+  SysUtils, Classes;
+
+
 // does filename have one of ".wad", ".pk3", ".zip" extensions?
 function hasWadExtension (fn: AnsiString): Boolean;
 
@@ -29,12 +33,12 @@ function utf8to1251 (s: AnsiString): AnsiString;
 // nobody cares about shitdoze, so i'll use the same code path for it
 function findFileCI (var pathname: AnsiString; lastIsDir: Boolean=false): Boolean;
 
+// they throws
+function openDiskFileRO (pathname: AnsiString): TStream;
+function createDiskFile (pathname: AnsiString): TStream;
 
-implementation
-
-uses
-  SysUtils;
 
+implementation
 
 function hasWadExtension (fn: AnsiString): Boolean;
 begin
@@ -308,4 +312,23 @@ begin
 end;
 
 
+function openDiskFileRO (pathname: AnsiString): TStream;
+begin
+  if not findFileCI(pathname) then raise Exception.Create('can''t open file "'+pathname+'"');
+  result := TFileStream.Create(pathname, fmOpenRead or {fmShareDenyWrite}fmShareDenyNone);
+end;
+
+function createDiskFile (pathname: AnsiString): TStream;
+var
+  path: AnsiString;
+begin
+  path := ExtractFilePath(pathname);
+  if length(path) > 0 then
+  begin
+    if not findFileCI(path, true) then raise Exception.Create('can''t create file "'+pathname+'"');
+  end;
+  result := TFileStream.Create(path+ExtractFileName(pathname), fmCreate);
+end;
+
+
 end.
diff --git a/src/shared/wadreader.pas b/src/shared/wadreader.pas
index 3cce5df..343c92f 100644
--- a/src/shared/wadreader.pas
+++ b/src/shared/wadreader.pas
@@ -13,7 +13,7 @@ type
 
   TWADFile = class(TObject)
   private
-    fFileName: string; // empty: not opened
+    fFileName: AnsiString; // empty: not opened
     fIter: TSFSFileList;
 
     function getIsOpen (): Boolean;
@@ -24,20 +24,20 @@ type
 
     procedure FreeWAD();
 
-    function ReadFile (FileName: string): Boolean;
+    function ReadFile (FileName: AnsiString): Boolean;
     function ReadMemory (Data: Pointer; Len: LongWord): Boolean;
-    function GetResource (Section, Resource: string; var pData: Pointer; var Len: Integer): Boolean;
-    function GetResourcesList (Section: string): SArray;
+    function GetResource (Section, Resource: AnsiString; var pData: Pointer; var Len: Integer): Boolean;
+    function GetResourcesList (Section: AnsiString): SArray;
 
     property isOpen: Boolean read getIsOpen;
   end;
 
 
-procedure g_ProcessResourceStr (ResourceStr: String; var FileName, SectionName, ResourceName: String); overload;
-procedure g_ProcessResourceStr (ResourceStr: String; FileName, SectionName, ResourceName: PString); overload;
+procedure g_ProcessResourceStr (ResourceStr: AnsiString; var FileName, SectionName, ResourceName: AnsiString); overload;
+procedure g_ProcessResourceStr (ResourceStr: AnsiString; FileName, SectionName, ResourceName: PString); overload;
 
-// return fixed string or empty string
-function findDiskWad (fname: string): string;
+// return fixed AnsiString or empty AnsiString
+function findDiskWad (fname: AnsiString): AnsiString;
 
 
 implementation
@@ -46,7 +46,7 @@ uses
   SysUtils, Classes, BinEditor, e_log, g_options, utils;
 
 
-function findDiskWad (fname: string): string;
+function findDiskWad (fname: AnsiString): AnsiString;
 begin
   result := '';
   if not findFileCI(fname) then
@@ -77,20 +77,14 @@ begin
 end;
 
 
-procedure g_ProcessResourceStr (ResourceStr: String; var FileName, SectionName, ResourceName: String);
+procedure g_ProcessResourceStr (ResourceStr: AnsiString; var FileName, SectionName, ResourceName: AnsiString);
 var
   a, i: Integer;
 begin
   //e_WriteLog(Format('g_ProcessResourceStr0: [%s]', [ResourceStr]), MSG_NOTIFY);
-  for i := Length(ResourceStr) downto 1 do
-    if ResourceStr[i] = ':' then
-      Break;
-
+  for i := Length(ResourceStr) downto 1 do if ResourceStr[i] = ':' then break;
   FileName := Copy(ResourceStr, 1, i-1);
-
-  for a := i+1 to Length(ResourceStr) do
-    if (ResourceStr[a] = '\') or (ResourceStr[a] = '/') then Break;
-
+  for a := i+1 to Length(ResourceStr) do if (ResourceStr[a] = '\') or (ResourceStr[a] = '/') then Break;
   ResourceName := Copy(ResourceStr, a+1, Length(ResourceStr)-Abs(a));
   SectionName := Copy(ResourceStr, i+1, Length(ResourceStr)-Length(ResourceName)-Length(FileName)-2);
 end;
@@ -99,34 +93,29 @@ end;
 procedure g_ProcessResourceStr (ResourceStr: AnsiString; FileName, SectionName, ResourceName: PAnsiString);
 var
   a, i, l1, l2: Integer;
-
 begin
   //e_WriteLog(Format('g_ProcessResourceStr1: [%s]', [ResourceStr]), MSG_NOTIFY);
-  for i := Length(ResourceStr) downto 1 do
-    if ResourceStr[i] = ':' then
-      Break;
-
+  for i := Length(ResourceStr) downto 1 do if ResourceStr[i] = ':' then break;
   if FileName <> nil then
-    begin
-      FileName^ := Copy(ResourceStr, 1, i-1);
-      l1 := Length(FileName^);
-    end
+  begin
+    FileName^ := Copy(ResourceStr, 1, i-1);
+    l1 := Length(FileName^);
+  end
   else
+  begin
     l1 := 0;
-
-  for a := i+1 to Length(ResourceStr) do
-    if (ResourceStr[a] = '\') or (ResourceStr[a] = '/') then Break;
-
+  end;
+  for a := i+1 to Length(ResourceStr) do if (ResourceStr[a] = '\') or (ResourceStr[a] = '/') then break;
   if ResourceName <> nil then
-    begin
-      ResourceName^ := Copy(ResourceStr, a+1, Length(ResourceStr)-Abs(a));
-      l2 := Length(ResourceName^);
-    end
+  begin
+    ResourceName^ := Copy(ResourceStr, a+1, Length(ResourceStr)-Abs(a));
+    l2 := Length(ResourceName^);
+  end
   else
+  begin
     l2 := 0;
-
-  if SectionName <> nil then
-    SectionName^ := Copy(ResourceStr, i+1, Length(ResourceStr)-l2-l1-2);
+  end;
+  if SectionName <> nil then SectionName^ := Copy(ResourceStr, i+1, Length(ResourceStr)-l2-l1-2);
 end;
 
 
@@ -158,7 +147,7 @@ begin
 end;
 
 
-function removeExt (s: string): string;
+function removeExt (s: AnsiString): AnsiString;
 var
   i: Integer;
 begin
@@ -172,13 +161,13 @@ begin
   result := s;
 end;
 
-function TWADFile.GetResource (Section, Resource: string; var pData: Pointer; var Len: Integer): Boolean;
+function TWADFile.GetResource (Section, Resource: AnsiString; var pData: Pointer; var Len: Integer): Boolean;
 var
   f: Integer;
   fi: TSFSFileInfo;
   fs: TStream;
   fpp: Pointer;
-  //fn: string;
+  //fn: AnsiString;
 begin
   Result := False;
   if not isOpen or (fIter = nil) then Exit;
@@ -232,7 +221,7 @@ begin
 end;
 
 
-function TWADFile.GetResourcesList (Section: string): SArray;
+function TWADFile.GetResourcesList (Section: AnsiString): SArray;
 var
   f: Integer;
   fi: TSFSFileInfo;
@@ -254,9 +243,9 @@ begin
 end;
 
 
-function TWADFile.ReadFile (FileName: string): Boolean;
+function TWADFile.ReadFile (FileName: AnsiString): Boolean;
 var
-  rfn: string;
+  rfn: AnsiString;
   //f: Integer;
   //fi: TSFSFileInfo;
 begin
@@ -300,7 +289,7 @@ var
 
 function TWADFile.ReadMemory (Data: Pointer; Len: LongWord): Boolean;
 var
-  fn: string;
+  fn: AnsiString;
   st: TStream = nil;
   //f: Integer;
   //fi: TSFSFileInfo;
diff --git a/src/sfs/xstreams.pas b/src/shared/xstreams.pas
similarity index 63%
rename from src/sfs/xstreams.pas
rename to src/shared/xstreams.pas
index 1861c61..f62582b 100644
--- a/src/sfs/xstreams.pas
+++ b/src/shared/xstreams.pas
@@ -1,29 +1,17 @@
 // special stream classes
-{$MODE DELPHI}
-{.$R-}
+{$MODE OBJFPC}
+{$R+}
 unit xstreams;
 
 interface
 
 uses
-  SysUtils, Classes, SDL2;
+  SysUtils, Classes,
+  zbase{z_stream};
 
 
 type
-  // ïîòîê-îá¸ðòêà äëÿ SDL_RWops
-  TSFSSDLStream = class(TStream)
-  protected
-    fRW: PSDL_RWops;      // SDL-íàÿ ïðîêëàäêà
-    fFreeSource: Boolean; // óáèâàòü èñõîäíèê ïðè ïîìèðàíèè?
-
-  public
-    constructor Create (aSrc: PSDL_RWops; aFreeSource: Boolean=true);
-    destructor Destroy (); override;
-
-    function Read (var buffer; count: LongInt): LongInt; override;
-    function Write (const buffer; count: LongInt): LongInt; override;
-    function Seek (const offset: Int64; origin: TSeekOrigin): Int64; override;
-  end;
+  XStreamError = class(Exception);
 
   // read-only ïîòîê äëÿ èçâëå÷åíèÿ èç èñõîäíîãî òîëüêî êóñî÷êà
   TSFSPartialStream = class(TStream)
@@ -62,6 +50,7 @@ type
     function Seek (const offset: Int64; origin: TSeekOrigin): Int64; override;
   end;
 
+  // this stream can kill both `proxied` and `guarded` streams on closing
   TSFSGuardStream = class(TStream)
   protected
     fSource: TStream;        // èñõîäíûé ïîòîê
@@ -96,54 +85,36 @@ type
     function Write (const buffer; count: LongInt): LongInt; override;
   end;
 
+  TUnZStream = class(TStream)
+  protected
+    fSrcSt: TStream;
+    fZlibSt: z_stream;
+    fBuffer: PByte;
+    fPos: Int64;
+    fSkipHeader: Boolean;
+    fSize: Int64; // can be -1
+    fSrcStPos: Int64;
+    fSkipToPos: Int64; // >0: skip to this position
+
+    procedure reset ();
+    function readBuf (var buffer; count: LongInt): LongInt;
+    procedure fixPos ();
+    procedure determineSize ();
 
-implementation
-
-uses
-  sfs; // for ESFSError
-
-{ TSFSSDLStream }
-constructor TSFSSDLStream.Create (aSrc: PSDL_RWops; aFreeSource: Boolean=true);
-begin
-  inherited Create();
-  //ASSERT(aSrc <> nil);
-  fRW := aSrc;
-  fFreeSource := aFreeSource;
-end;
-
-destructor TSFSSDLStream.Destroy ();
-begin
-  if fFreeSource and (fRW <> nil) then SDL_FreeRW(fRW);
-  inherited Destroy();
-end;
+  public
+    // `aSize` can be -1 if stream size is unknown
+    constructor create (asrc: TStream; aSize: Int64; aSkipHeader: boolean=false);
+    destructor destroy (); override;
+    function read (var buffer; count: LongInt): LongInt; override;
+    function write (const buffer; count: LongInt): LongInt; override;
+    function seek (const offset: Int64; origin: TSeekOrigin): Int64; override;
+  end;
 
-function TSFSSDLStream.Read (var buffer; count: LongInt): LongInt;
-begin
-  if (fRW = nil) or (count <= 0) then begin result := 0; exit; end;
-  result := SDL_RWread(fRW, @buffer, 1, count);
-end;
 
-function TSFSSDLStream.Write (const buffer; count: LongInt): LongInt;
-begin
-  if (fRW = nil) or (count <= 0) then begin result := 0; exit; end;
-  result := SDL_RWwrite(fRW, @buffer, 1, count);
-end;
+implementation
 
-function TSFSSDLStream.Seek (const offset: Int64; origin: TSeekOrigin): Int64;
-var
-  ss: Integer;
-begin
-  if fRW = nil then begin result := 0; exit; end;
-  case origin of
-    soBeginning: ss := RW_SEEK_SET;
-    soCurrent: ss := RW_SEEK_CUR;
-    soEnd: ss := RW_SEEK_END;
-    else raise ESFSError.Create('invalid Seek() call');
-    // äðóãèõ íå áûâàåò. à ó êîãî áûâàåò, òîìó ÿ íå äîêòîð.
-  end;
-  result := SDL_RWseek(fRW, offset, ss);
-  if result = -1 then raise ESFSError.Create('Seek() error');
-end;
+uses
+  zinflate;
 
 
 { TSFSPartialStream }
@@ -196,7 +167,7 @@ end;
 function TSFSPartialStream.Write (const buffer; count: LongInt): LongInt;
 begin
   result := 0;
-  raise ESFSError.Create('can''t write to read-only stream');
+  raise XStreamError.Create('can''t write to read-only stream');
   // à íå õîäè, íåõîðîøèé, â íàø ñàäèê ãóëÿòü!
 end;
 
@@ -206,7 +177,7 @@ var
   pc: Pointer;
   rd: LongInt;
 begin
-  if count < 0 then raise ESFSError.Create('invalid Read() call'); // ñêàçî÷íûé äîëáî¸á...
+  if count < 0 then raise XStreamError.Create('invalid Read() call'); // ñêàçî÷íûé äîëáî¸á...
   if count = 0 then begin result := 0; exit; end;
   pc := @buffer;
   result := 0;
@@ -248,7 +219,7 @@ begin
     soBeginning: result := offset;
     soCurrent: result := offset+fCurrentPos;
     soEnd: result := fSize+offset;
-    else raise ESFSError.Create('invalid Seek() call');
+    else raise XStreamError.Create('invalid Seek() call');
     // äðóãèõ íå áûâàåò. à ó êîãî áûâàåò, òîìó ÿ íå äîêòîð.
   end;
   if result < 0 then result := 0
@@ -308,9 +279,131 @@ end;
 function TSFSMemoryStreamRO.Write (const buffer; count: LongInt): LongInt;
 begin
   result := 0;
-  raise ESFSError.Create('can''t write to read-only stream');
+  raise XStreamError.Create('can''t write to read-only stream');
   // ñîâñåì ñáðåíäèë...
 end;
 
 
+// ////////////////////////////////////////////////////////////////////////// //
+{ TUnZStream }
+const ZBufSize = 32768; // size of the buffer used for temporarily storing data from the child stream
+
+constructor TUnZStream.create (asrc: TStream; aSize: Int64; aSkipHeader: boolean=false);
+var
+  err: Integer;
+begin
+  fPos := 0;
+  fSkipToPos := -1;
+  fSrcSt := asrc;
+  fSize := aSize;
+  GetMem(fBuffer, ZBufSize);
+  fSkipHeader := aSkipHeader;
+  if fSkipHeader then err := inflateInit2(fZlibSt, -MAX_WBITS) else err := inflateInit(fZlibSt);
+  if err <> Z_OK then raise XStreamError.Create(zerror(err));
+  fSrcStPos := fSrcSt.position;
+end;
+
+destructor TUnZStream.destroy ();
+begin
+  inflateEnd(fZlibSt);
+  FreeMem(fBuffer);
+  fSrcSt.Free;
+  inherited destroy;
+end;
+
+function TUnZStream.readBuf (var buffer; count: LongInt): LongInt;
+var
+  err: Integer;
+  lastavail: LongInt;
+begin
+  fZlibSt.next_out := @buffer;
+  fZlibSt.avail_out := count;
+  lastavail := count;
+  while fZlibSt.avail_out <> 0 do
+  begin
+    if fZlibSt.avail_in = 0 then
+    begin
+      // refill the buffer
+      fZlibSt.next_in := fBuffer;
+      fZlibSt.avail_in := fSrcSt.read(Fbuffer^, ZBufSize);
+      //Inc(compressed_read, fZlibSt.avail_in);
+      Inc(fPos, lastavail-fZlibSt.avail_out);
+      lastavail := fZlibSt.avail_out;
+    end;
+    err := inflate(fZlibSt, Z_NO_FLUSH);
+    if err = Z_STREAM_END then fSize := fPos; break;
+    if err <> Z_OK then raise XStreamError.Create(zerror(err));
+  end;
+  //if err = Z_STREAM_END then Dec(compressed_read, fZlibSt.avail_in);
+  Inc(fPos, lastavail-fZlibSt.avail_out);
+  result := count-fZlibSt.avail_out;
+end;
+
+procedure TUnZStream.fixPos ();
+var
+  buf: array [0..4095] of Byte;
+  rd, rr: LongInt;
+begin
+  if fSkipToPos < 0 then exit;
+  if fSkipToPos > fPos then reset();
+  while fPos < fSkipToPos do
+  begin
+    if fSkipToPos-fPos > 4096 then rd := 4096 else rd := LongInt(fSkipToPos-fPos);
+    rr := readBuf(buf, rd);
+    if rd <> rr then raise XStreamError.Create('seek error');
+  end;
+  fSkipToPos := -1;
+end;
+
+procedure TUnZStream.determineSize ();
+var
+  buf: array [0..4095] of Byte;
+  rd: LongInt;
+begin
+  if fSize >= 0 then exit;
+  while true do
+  begin
+    rd := readBuf(buf, 4096);
+    if rd <> 4096 then break;
+  end;
+  fSize := fPos;
+end;
+
+function TUnZStream.read (var buffer; count: LongInt): LongInt;
+begin
+  if fSkipToPos >= 0 then fixPos();
+  result := readBuf(buffer, count);
+end;
+
+function TUnZStream.write (const buffer; count: LongInt): LongInt;
+begin
+  result := 0;
+  raise XStreamError.Create('can''t write to read-only stream');
+end;
+
+procedure TUnZStream.reset ();
+var
+  err: Integer;
+begin
+  fSrcSt.position := fSrcStPos;
+  fPos := 0;
+  inflateEnd(fZlibSt);
+  if fSkipHeader then err := inflateInit2(fZlibSt, -MAX_WBITS) else err := inflateInit(fZlibSt);
+  if err <> Z_OK then raise XStreamError.Create(zerror(err));
+end;
+
+function TUnZStream.Seek (const offset: Int64; origin: TSeekOrigin): Int64;
+begin
+  case origin of
+    soBeginning: result := offset;
+    soCurrent: result := offset+fPos;
+    soEnd: begin if fSize = -1 then determineSize(); result := fSize+offset; end;
+    else raise XStreamError.Create('invalid Seek() call');
+    // äðóãèõ íå áûâàåò. à ó êîãî áûâàåò, òîìó ÿ íå äîêòîð.
+  end;
+  if result < 0 then result := 0;
+  fSkipToPos := result;
+end;
+
+
 end.
diff --git a/src/unused/xstreams_sdl.pas b/src/unused/xstreams_sdl.pas
new file mode 100644
index 0000000..3bc2c64
--- /dev/null
+++ b/src/unused/xstreams_sdl.pas
@@ -0,0 +1,76 @@
+// special stream classes
+{$MODE OBJFPC}
+{$R+}
+unit xstreams_sdl;
+
+interface
+
+uses
+  SysUtils, Classes, xstreams;
+
+
+type
+  // ïîòîê-îá¸ðòêà äëÿ SDL_RWops
+  TSFSSDLStream = class(TStream)
+  protected
+    fRW: PSDL_RWops;      // SDL-íàÿ ïðîêëàäêà
+    fFreeSource: Boolean; // óáèâàòü èñõîäíèê ïðè ïîìèðàíèè?
+
+  public
+    constructor Create (aSrc: PSDL_RWops; aFreeSource: Boolean=true);
+    destructor Destroy (); override;
+
+    function Read (var buffer; count: LongInt): LongInt; override;
+    function Write (const buffer; count: LongInt): LongInt; override;
+    function Seek (const offset: Int64; origin: TSeekOrigin): Int64; override;
+  end;
+
+
+implementation
+
+
+{ TSFSSDLStream }
+constructor TSFSSDLStream.Create (aSrc: PSDL_RWops; aFreeSource: Boolean=true);
+begin
+  inherited Create();
+  //ASSERT(aSrc <> nil);
+  fRW := aSrc;
+  fFreeSource := aFreeSource;
+end;
+
+destructor TSFSSDLStream.Destroy ();
+begin
+  if fFreeSource and (fRW <> nil) then SDL_FreeRW(fRW);
+  inherited Destroy();
+end;
+
+function TSFSSDLStream.Read (var buffer; count: LongInt): LongInt;
+begin
+  if (fRW = nil) or (count <= 0) then begin result := 0; exit; end;
+  result := SDL_RWread(fRW, @buffer, 1, count);
+end;
+
+function TSFSSDLStream.Write (const buffer; count: LongInt): LongInt;
+begin
+  if (fRW = nil) or (count <= 0) then begin result := 0; exit; end;
+  result := SDL_RWwrite(fRW, @buffer, 1, count);
+end;
+
+function TSFSSDLStream.Seek (const offset: Int64; origin: TSeekOrigin): Int64;
+var
+  ss: Integer;
+begin
+  if fRW = nil then begin result := 0; exit; end;
+  case origin of
+    soBeginning: ss := RW_SEEK_SET;
+    soCurrent: ss := RW_SEEK_CUR;
+    soEnd: ss := RW_SEEK_END;
+    else raise XStreamError.Create('invalid Seek() call');
+    // äðóãèõ íå áûâàåò. à ó êîãî áûâàåò, òîìó ÿ íå äîêòîð.
+  end;
+  result := SDL_RWseek(fRW, offset, ss);
+  if result = -1 then raise XStreamError.Create('Seek() error');
+end;
+
+
+end.
-- 
2.29.2