X-Git-Url: http://deadsoftware.ru/gitweb?a=blobdiff_plain;f=src%2Fshared%2Fxstreams.pas;h=e27f73ad0eb9c94c8f964649e0d969a22b0e78e6;hb=e7e94dcc4a3c33072237faead3efa1029711c208;hp=e7e70e70ef79769651fb825edf1243e1f243ef3d;hpb=b8fa6d703be4f383a2be1f3ed093a597c2ad6829;p=d2df-sdl.git

diff --git a/src/shared/xstreams.pas b/src/shared/xstreams.pas
index e7e70e7..e27f73a 100644
--- a/src/shared/xstreams.pas
+++ b/src/shared/xstreams.pas
@@ -1,6 +1,21 @@
+(* Copyright (C)  Doom 2D: Forever Developers
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ *)
 // special stream classes
-{$MODE DELPHI}
-{$R+}
+{$INCLUDE a_modes.inc}
+{.$R+}
 unit xstreams;
 
 interface
@@ -111,6 +126,29 @@ type
     function seek (const offset: Int64; origin: TSeekOrigin): Int64; override;
   end;
 
+  // fixed memory chunk
+  TSFSMemoryChunkStream = class(TStream)
+  private
+    fFreeMem: Boolean;
+    fMemBuf: PByte;
+    fMemSize: Integer;
+    fCurPos: Integer;
+
+  public
+    // if `pMem` is `nil`, stream will allocate it
+    constructor Create (pMem: Pointer; pSize: Integer; aFreeMem: Boolean=false);
+    destructor Destroy (); override;
+
+    procedure setup (pMem: Pointer; pSize: Integer; aFreeMem: Boolean=false);
+
+    function Seek (const offset: Int64; origin: TSeekOrigin): Int64; override;
+    function Read (var buffer; count: LongInt): LongInt; override;
+    function Write (const buffer; count: LongInt): LongInt; override;
+
+    property chunkSize: Integer read fMemSize;
+    property chunkData: PByte read fMemBuf;
+  end;
+
 
 implementation
 
@@ -301,9 +339,10 @@ begin
   fSize := aSize;
   GetMem(fBuffer, ZBufSize);
   fSkipHeader := aSkipHeader;
+  fSrcStPos := fSrcSt.position;
+  FillChar(fZlibSt, sizeof(fZlibSt), 0);
   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;
 
 
@@ -322,6 +361,7 @@ var
   sz: LongInt;
 begin
   result := 0;
+  if (fSize >= 0) and (fPos >= fSize) then exit;
   if count > 0 then
   begin
     fZlibSt.next_out := @buffer;
@@ -360,7 +400,7 @@ begin
     //writeln('  reading ', rd, ' bytes...');
     rr := readBuf(buf, rd);
     //writeln('  got ', rr, ' bytes; fPos=', fPos, '; fSkipToPos=', fSkipToPos);
-    if rd <> rr then raise XStreamError.Create('seek error');
+    if rr <= 0 then raise XStreamError.Create('seek error');
   end;
   //writeln('  pos: fPos=', fPos, '; fSkipToPos=', fSkipToPos);
   fSkipToPos := -1;
@@ -380,12 +420,12 @@ begin
     while true do
     begin
       rd := readBuf(buf, 4096);
-      if rd <> 4096 then break;
+      if rd = 0 then break;
     end;
     fSize := fPos;
     //writeln('  unzstream size is ', fSize);
   finally
-    fSkipToPos := opos;
+    if fSkipToPos < 0 then fSkipToPos := opos;
   end;
 end;
 
@@ -408,9 +448,11 @@ procedure TUnZStream.reset ();
 var
   err: Integer;
 begin
+  //writeln('doing RESET');
   fSrcSt.position := fSrcStPos;
   fPos := 0;
   inflateEnd(fZlibSt);
+  FillChar(fZlibSt, sizeof(fZlibSt), 0);
   if fSkipHeader then err := inflateInit2(fZlibSt, -MAX_WBITS) else err := inflateInit(fZlibSt);
   if err <> Z_OK then raise XStreamError.Create(zerror(err));
 end;
@@ -435,4 +477,91 @@ begin
 end;
 
 
+// ////////////////////////////////////////////////////////////////////////// //
+constructor TSFSMemoryChunkStream.Create (pMem: Pointer; pSize: Integer; aFreeMem: Boolean=false);
+begin
+  fMemBuf := nil;
+  fFreeMem := false;
+  fMemSize := 0;
+  fCurPos := 0;
+  setup(pMem, pSize, aFreeMem);
+end;
+
+
+procedure TSFSMemoryChunkStream.setup (pMem: Pointer; pSize: Integer; aFreeMem: Boolean=false);
+begin
+  if fFreeMem then FreeMem(fMemBuf);
+  fMemBuf := nil;
+  fFreeMem := false;
+  fMemSize := 0;
+  fCurPos := 0;
+  if (pSize < 0) then raise XStreamError.Create('invalid chunk size');
+  if (pMem = nil) then
+  begin
+    if (pSize > 0) then
+    begin
+      GetMem(pMem, pSize);
+      if (pMem = nil) then raise XStreamError.Create('out of memory for chunk');
+      aFreeMem := true;
+    end
+    else
+    begin
+      aFreeMem := false;
+    end;
+  end;
+  fFreeMem := aFreeMem;
+  fMemBuf := PByte(pMem);
+  fMemSize := pSize;
+end;
+
+
+destructor TSFSMemoryChunkStream.Destroy ();
+begin
+  if fFreeMem then FreeMem(fMemBuf);
+  inherited;
+end;
+
+
+function TSFSMemoryChunkStream.Seek (const offset: Int64; origin: TSeekOrigin): Int64;
+begin
+  case origin of
+    soBeginning: result := offset;
+    soCurrent: result := offset+fCurPos;
+    soEnd: result := fMemSize+offset;
+    else raise XStreamError.Create('invalid Seek() call');
+  end;
+  if (result < 0) then raise XStreamError.Create('invalid Seek() call');
+  if (result > fMemSize) then result := fMemSize;
+  fCurPos := result;
+end;
+
+
+function TSFSMemoryChunkStream.Read (var buffer; count: LongInt): LongInt;
+var
+  left: Integer;
+begin
+  if (count < 0) then raise XStreamError.Create('negative read');
+  left := fMemSize-fCurPos;
+  if (left < 0) then raise XStreamError.Create('internal error in TSFSMemoryChunkStream (read)');
+  if (count > left) then count := left;
+  if (count > 0) then Move((fMemBuf+fCurPos)^, buffer, count);
+  Inc(fCurPos, count);
+  result := count;
+end;
+
+
+function TSFSMemoryChunkStream.Write (const buffer; count: LongInt): LongInt;
+var
+  left: Integer;
+begin
+  if (count < 0) then raise XStreamError.Create('negative write');
+  left := fMemSize-fCurPos;
+  if (left < 0) then raise XStreamError.Create('internal error in TSFSMemoryChunkStream (write)');
+  if (count > left) then count := left;
+  if (count > 0) then Move(buffer, (fMemBuf+fCurPos)^, count);
+  Inc(fCurPos, count);
+  result := count;
+end;
+
+
 end.