Copyright 1996-2003 John D. Polstra.
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. All advertising materials mentioning features or use of this software
* must display the following acknowledgment:
* This product includes software developed by John D. Polstra.
* 4. The name of the author may not be used to endorse or promote products
* derived from this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
* IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
* OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
* IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
* NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
* THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*
* $Id: GzipWr.m3.html,v 1.3 2010-04-29 17:20:02 wagner Exp $
UNSAFE MODULE GzipWr;
IMPORT
GzipError, OSError, StreamWrClass, Thread, Ugzip, Wr, WrClass;
FROM Ctypes IMPORT unsigned_char_star;
REVEAL
T = Public BRANDED OBJECT
wr: Wr.T;
closeChild: BOOLEAN;
strmp: Ugzip.z_stream_star := NIL;
OVERRIDES
init := Init;
seek := Seek;
flush := Flush;
close := Close;
END;
PROCEDURE Cleanup(self: T) =
BEGIN
IF self.strmp # NIL THEN
IF self.strmp.state # NIL THEN
EVAL Ugzip.deflateEnd(self.strmp);
END;
DISPOSE(self.strmp);
END;
END Cleanup;
PROCEDURE Close(self: T)
RAISES {Thread.Alerted, Wr.Failure} =
VAR
status: INTEGER;
BEGIN
TRY
TRY
REPEAT
IF self.wr.cur = self.wr.hi THEN (* Must flush the output buffer. *)
self.wr.seek(self.wr.cur);
END;
status := Deflate(self.strmp,
ADR(self.buff[self.st]),
0,
ADR(self.wr.buff[self.wr.st]) + self.wr.cur - self.wr.lo,
self.wr.hi - self.wr.cur,
Ugzip.Z_FINISH);
IF status # Ugzip.Z_OK AND status # Ugzip.Z_STREAM_END THEN
RAISE Wr.Failure(GzipError.FromStatus(status));
END;
self.wr.cur := self.wr.hi - self.strmp.avail_out;
UNTIL status = Ugzip.Z_STREAM_END;
self.wr.flush(); (* FIXME - Is this necessary? *)
FINALLY
status := Ugzip.deflateEnd(self.strmp);
DISPOSE(self.strmp);
IF status # Ugzip.Z_OK THEN
RAISE Wr.Failure(GzipError.FromStatus(status));
END;
END;
FINALLY
IF self.closeChild THEN
Wr.Close(self.wr);
END;
END;
END Close;
PROCEDURE Deflate(strmp: Ugzip.z_stream_star;
next_in: unsigned_char_star;
avail_in: CARDINAL;
next_out: unsigned_char_star;
avail_out: CARDINAL;
flush: INTEGER): INTEGER =
Call Ugzip.deflate
, making sure that pointers into the (traced)
input and output buffers are on the stack or in registers. This
ensures that the collector will not move the buffers.
BEGIN
strmp.next_in := next_in;
strmp.avail_in := avail_in;
strmp.next_out := next_out;
strmp.avail_out := avail_out;
RETURN Ugzip.deflate(strmp, flush);
END Deflate;
PROCEDURE Flush(self: T)
RAISES {Thread.Alerted, Wr.Failure} =
VAR
status: INTEGER;
BEGIN
Seek(self, self.cur); (* Compress everything in the input buffer. *)
REPEAT
IF self.wr.cur = self.wr.hi THEN (* Must flush the output buffer. *)
self.wr.seek(self.wr.cur);
END;
status := Deflate(self.strmp,
ADR(self.buff[self.st]),
0,
ADR(self.wr.buff[self.wr.st]) + self.wr.cur - self.wr.lo,
self.wr.hi - self.wr.cur,
Ugzip.Z_PARTIAL_FLUSH);
IF status # Ugzip.Z_OK AND status # Ugzip.Z_BUF_ERROR THEN
RAISE Wr.Failure(GzipError.FromStatus(status));
END;
self.wr.cur := self.wr.hi - self.strmp.avail_out;
UNTIL self.strmp.avail_out > 0;
self.wr.flush();
END Flush;
PROCEDURE Init(self: T;
wr: Wr.T; level: CompLevel := -1;
closeChild: BOOLEAN := TRUE): T
RAISES {OSError.E} =
VAR
status: INTEGER;
BEGIN
WrClass.Lock(self);
TRY
self.wr := wr;
self.closeChild := closeChild;
self.buff := NEW(REF ARRAY OF CHAR, 8192);
self.st := 0;
self.hi := NUMBER(self.buff^);
self.seekable := FALSE;
self.buffered := wr.buffered;
self.closed := FALSE;
self.strmp := NEW(Ugzip.z_stream_star,
zalloc := Ugzip.SafeAlloc,
zfree := Ugzip.SafeFree,
opaque := NIL,
state := NIL);
status := Ugzip.deflateInit(self.strmp, level);
IF status # Ugzip.Z_OK THEN
RAISE OSError.E(GzipError.FromStatus(status));
END;
FINALLY
WrClass.Unlock(self);
END;
RETURN self;
END Init;
PROCEDURE Seek(self: T; n: CARDINAL)
RAISES {Thread.Alerted, Wr.Failure} =
VAR
oldLo: CARDINAL;
status: INTEGER;
BEGIN
<* ASSERT n = self.cur *>
oldLo := self.lo;
WHILE self.lo < self.cur DO (* There is more in the input buffer. *)
IF self.wr.cur = self.wr.hi THEN (* Must flush the output buffer. *)
self.wr.seek(self.wr.cur);
END;
status := Deflate(self.strmp,
ADR(self.buff[self.st]) + self.lo - oldLo,
self.cur - self.lo,
ADR(self.wr.buff[self.wr.st]) + self.wr.cur - self.wr.lo,
self.wr.hi - self.wr.cur,
Ugzip.Z_NO_FLUSH);
IF status # Ugzip.Z_OK THEN
RAISE Wr.Failure(GzipError.FromStatus(status));
END;
self.lo := self.cur - self.strmp.avail_in;
self.wr.cur := self.wr.hi - self.strmp.avail_out;
END;
self.hi := self.lo + NUMBER(self.buff^) - self.st;
StreamWrClass.DontOverflow(self);
END Seek;
BEGIN
END GzipWr.