zlib 0.99

2011-09-09 23:11:37 -07:00
33 changed files with 1833 additions and 775 deletions
--- a/61
+++ b/61
@@ -1,6 +1,67 @@

 		ChangeLog file for zlib

+Changes in 1.0 (15 Jan 96)
+- allow preset dictionary shared between compressor and decompressor
+- allow compression level 0 (no compression)
+- add deflateParams in zlib.h: allow dynamic change of compression level
+  and compression strategy.
+- test large buffers and deflateParams in example.c
+- add optional "configure" to build zlib as a shared library
+- suppress Makefile.qnx, use configure instead
+- fixed deflate for 64-bit systems (detected on Cray)
+- fixed inflate_blocks for 64-bit systems (detected on Alpha)
+- declare Z_DEFLATED in zlib.h (possible parameter for deflateInit2)
+- always return Z_BUF_ERROR when deflate() has nothing to do
+- deflateInit and inflateInit are now macros to allow version checking
+- prefix all global functions and types with z_ with -DZ_PREFIX
+- make falloc completely reentrant (inftrees.c)
+- fixed very unlikely race condition in ct_static_init
+- free in reverse order of allocation to help memory manager
+- use zlib-1.0/* instead of zlib/* inside the tar.gz
+- make zlib warning-free with "gcc -O3 -Wall -Wwrite-strings -Wpointer-arith
+  -Wconversion -Wstrict-prototypes -Wmissing-prototypes"
+- allow gzread on concatenated .gz files
+- deflateEnd now returns Z_DATA_ERROR if it was premature
+- deflate is finally (?) fully deterministic (no matches beyond end of input)
+- Document Z_SYNC_FLUSH
+- add uninstall in Makefile
+- Check for __cpluplus in zlib.h
+- Better test in ct_align for partial flush
+- avoid harmless warnings for Borland C++
+- initialize hash_head in deflate.c
+- avoid warning on fdopen (gzio.c) for HP cc -Aa
+- include stdlib.h for STDC compilers
+- include errno.h for Cray
+- ignore error if ranlib doesn't exist
+- call ranlib twice for NeXTSTEP
+- use exec_prefix instead of prefix for libz.a
+- renamed ct_* as _tr_* to avoid conflict with applications
+- clear z->msg in inflateInit2 before any error return
+- initialize opaque in example.c, gzio.c, deflate.c and inflate.c
+- fixed typo in zconf.h (_GNUC__ => __GNUC__)
+- check for WIN32 in zconf.h and zutil.c (avoid farmalloc in 32-bit mode)
+- fix typo in Make_vms.com (f$trnlnm -> f$getsyi)
+- in fcalloc, normalize pointer if size > 65520 bytes
+- don't use special fcalloc for 32 bit Borland C++
+- use STDC instead of __GO32__ to avoid redeclaring exit, calloc, etc...
+- use Z_BINARY instead of BINARY
+- document that gzclose after gzdopen will close the file
+- allow "a" as mode in gzopen.
+- fix error checking in gzread
+- allow skipping .gz extra-field on pipes
+- added reference to Perl interface in README
+- put the crc table in FAR data (I dislike more and more the medium model :)
+- added get_crc_table
+- added a dimension to all arrays (Borland C can't count).
+- workaround Borland C bug in declaration of inflate_codes_new & inflate_fast
+- guard against multiple inclusion of *.h (for precompiled header on Mac)
+- Watcom C pretends to be Microsoft C small model even in 32 bit mode.
+- don't use unsized arrays to avoid silly warnings by Visual C++:
+     warning C4746: 'inflate_mask' : unsized array treated as  '__far'
+     (what's wrong with far data in far model?).
+- define enum out of inflate_blocks_state to allow compilation with C++
+
 Changes in 0.95 (16 Aug 95)
 - fix MSDOS small and medium model (now easier to adapt to any compiler)
 - inlined send_bits
--- a/Make_vms.com
+++ b/Make_vms.com
@@ -4,7 +4,7 @@ $!
 $! Look for the compiler used
 $!
 $ ccopt = ""
-$ if f$trnlnm("HW_MODEL").ge.1024
+$ if f$getsyi("HW_MODEL").ge.1024
 $ then
 $  ccopt = "/prefix=all"+ccopt
 $  comp  = "__decc__=1"
--- a/121
+++ b/121
@@ -1,73 +1,130 @@
 # Makefile for zlib
-# Copyright (C) 1995 Jean-loup Gailly.
+# Copyright (C) 1995-1996 Jean-loup Gailly.
 # For conditions of distribution and use, see copyright notice in zlib.h 

-CC=cc
-CFLAGS=-O
-#use -O3 for gcc to take advantage of inlining
-#CFLAGS="-O -DMAX_WBITS=14 -DMAX_MEM_LEVEL=7"
-#CFLAGS=-g -DDEBUG
-LDFLAGS=-L. -lz
+# To compile and test, type:
+#   ./configure; make test
+# The call of configure is optional if you don't have special requirements

+# To install /usr/local/lib/libz.* and /usr/local/include/zlib.h, type:
+#    make install
+# To install in $HOME instead of /usr/local, use:
+#    make install prefix=$HOME
+
+CC=cc
+
+CFLAGS=-O
+#CFLAGS=-O -DMAX_WBITS=14 -DMAX_MEM_LEVEL=7
+#CFLAGS=-g -DDEBUG
+#CFLAGS=-O3 -Wall -Wwrite-strings -Wpointer-arith -Wconversion \
+#           -Wstrict-prototypes -Wmissing-prototypes
+
+LDFLAGS=-L. -lz
+LDSHARED=$(CC)
+
+VER=1.0
+LIBS=libz.a
+
+AR=ar rc
 RANLIB=ranlib
+TAR=tar

 prefix=/usr/local
+exec_prefix = $(prefix)

 OBJS = adler32.o compress.o crc32.o gzio.o uncompr.o deflate.o trees.o \
       zutil.o inflate.o infblock.o inftrees.o infcodes.o infutil.o inffast.o

 TEST_OBJS = example.o minigzip.o

+DISTFILES = README ChangeLog configure Makefile.in Makefile Makefile.msc \
+	    Makefile.bor Makefile.tc Make_vms.com descrip.mms *.[ch]
+
 all: example minigzip

 test: all
 	./example
 	echo hello world | ./minigzip | ./minigzip -d 

-install: libz.a
-	-@mkdir $(prefix)/include
-	-@mkdir $(prefix)/lib
-	cp zlib.h zconf.h $(prefix)/include
-	chmod 644 $(prefix)/include/zlib.h $(prefix)/include/zconf.h
-	cp libz.a $(prefix)/lib
-	chmod 644 $(prefix)/lib/libz.a
-
 libz.a: $(OBJS)
-	ar rc $@ $(OBJS)
-	$(RANLIB) $@
+	$(AR) $@ $(OBJS)
+	-@ ($(RANLIB) $@ || true) 2>/dev/null

-example: example.o libz.a
+libz.so.$(VER): $(OBJS)
+	$(LDSHARED) -o $@ $(OBJS)
+	rm -f libz.so; ln -s $@ libz.so
+
+example: example.o $(LIBS)
 	$(CC) $(CFLAGS) -o $@ example.o $(LDFLAGS)

-minigzip: minigzip.o libz.a
+minigzip: minigzip.o $(LIBS)
 	$(CC) $(CFLAGS) -o $@ minigzip.o $(LDFLAGS)

+install: $(LIBS)
+	-@if [ ! $(prefix)/include  ]; then mkdir $(prefix)/include; fi
+	-@if [ ! $(exec_prefix)/lib ]; then mkdir $(exec_prefix)/lib; fi
+	cp zlib.h zconf.h $(prefix)/include
+	chmod 644 $(prefix)/include/zlib.h $(prefix)/include/zconf.h
+	cp $(LIBS) $(exec_prefix)/lib
+	cd $(exec_prefix)/lib; chmod 644 $(LIBS)
+	-@(cd $(exec_prefix)/lib; $(RANLIB) libz.a || true) >/dev/null 2>&1
+	cd $(exec_prefix)/lib; if test -f libz.so.$(VER); then \
+	  ln -s libz.so.$(VER) libz.so; \
+	fi
+# The ranlib in install is needed on NeXTSTEP which checks file times
+
+uninstall:
+	cd $(exec_prefix)/lib; rm -f $(LIBS); \
+	if test -f libz.so; then \
+	 v=`sed -n '/VERSION "/s/.*"\(.*\)".*/\1/p'<$(prefix)/include/zlib.h`;\
+	 rm -f libz.so.$$v libz.so; \
+	fi
+	cd $(prefix)/include; rm -f zlib.h zconf.h
+
 clean:
-	rm -f *.o example minigzip libz.a foo.gz
+	rm -f *.o *~ example minigzip libz.a libz.so* foo.gz

 zip:
-	zip -ul9 zlib README ChangeLog Makefile Make????.??? Makefile.?? \
-	  descrip.mms *.[ch]
+	mv Makefile Makefile~; cp -p Makefile.in Makefile
+	v=`sed -n -e 's/\./-/' -e '/VERSION "/s/.*"\(.*\)".*/\1/p' < zlib.h`;\
+	zip -ul9 zlib-$$v $(DISTFILES)
+	mv Makefile~ Makefile

-tgz:
-	cd ..; tar cfz zlib/zlib.tgz zlib/README zlib/ChangeLog zlib/Makefile \
-	  zlib/Make????.??? zlib/Makefile.?? zlib/descrip.mms zlib/*.[ch]
+dist:
+	mv Makefile Makefile~; cp -p Makefile.in Makefile
+	d=zlib-`sed -n '/VERSION "/s/.*"\(.*\)".*/\1/p' < zlib.h`;\
+	rm -f $$d.tar.gz; \
+	if test ! -d ../$$d; then rm -f ../$$d; ln -s `pwd` ../$$d; fi; \
+	files=""; \
+	for f in $(DISTFILES); do files="$$files $$d/$$f"; done; \
+	cd ..; \
+	GZIP=-9 $(TAR) chofz $$d/$$d.tar.gz $$files; \
+	if test ! -d $$d; then rm -f $$d; fi
+	mv Makefile~ Makefile
+
+tags:	
+	etags *.[ch]
+
+depend:
+	makedepend -- $(CFLAGS) -- *.[ch]

 # DO NOT DELETE THIS LINE -- make depend depends on it.

-adler32.o: zutil.h zlib.h zconf.h
+adler32.o: zlib.h zconf.h
 compress.o: zlib.h zconf.h
-crc32.o: zutil.h zlib.h zconf.h
+crc32.o: zlib.h zconf.h
 deflate.o: deflate.h zutil.h zlib.h zconf.h
 example.o: zlib.h zconf.h
 gzio.o: zutil.h zlib.h zconf.h
-infblock.o: zutil.h zlib.h zconf.h infblock.h inftrees.h infcodes.h infutil.h
-infcodes.o: zutil.h zlib.h zconf.h inftrees.h infutil.h infcodes.h inffast.h
-inffast.o: zutil.h zlib.h zconf.h inftrees.h infutil.h inffast.h
+infblock.o: infblock.h inftrees.h infcodes.h infutil.h zutil.h zlib.h zconf.h
+infcodes.o: zutil.h zlib.h zconf.h
+infcodes.o: inftrees.h infblock.h infcodes.h infutil.h inffast.h
+inffast.o: zutil.h zlib.h zconf.h inftrees.h
+inffast.o: infblock.h infcodes.h infutil.h inffast.h
 inflate.o: zutil.h zlib.h zconf.h infblock.h
 inftrees.o: zutil.h zlib.h zconf.h inftrees.h
-infutil.o: zutil.h zlib.h zconf.h inftrees.h infutil.h
-minigzip.o: zlib.h zconf.h
+infutil.o: zutil.h zlib.h zconf.h infblock.h inftrees.h infcodes.h infutil.h
+minigzip.o:  zlib.h zconf.h 
 trees.o: deflate.h zutil.h zlib.h zconf.h 
 uncompr.o: zlib.h zconf.h
 zutil.o: zutil.h zlib.h zconf.h  
--- a/Makefile.bor
+++ b/Makefile.bor
@@ -18,7 +18,7 @@ CFLAGS=-O2 -Z $(MODEL)
 CC=bcc
 LD=bcc
 LIB=tlib
-#   replace bcc with tcc for Turbo C++ 1.0
+#   replace bcc with tcc for Turbo C++ 1.0, with bcc32 for the 32 bit version
 LDFLAGS=$(MODEL)
 O=.obj

--- a/Makefile.in
+++ b/Makefile.in
@@ -0,0 +1,130 @@
+# Makefile for zlib
+# Copyright (C) 1995-1996 Jean-loup Gailly.
+# For conditions of distribution and use, see copyright notice in zlib.h 
+
+# To compile and test, type:
+#   ./configure; make test
+# The call of configure is optional if you don't have special requirements
+
+# To install /usr/local/lib/libz.* and /usr/local/include/zlib.h, type:
+#    make install
+# To install in $HOME instead of /usr/local, use:
+#    make install prefix=$HOME
+
+CC=cc
+
+CFLAGS=-O
+#CFLAGS=-O -DMAX_WBITS=14 -DMAX_MEM_LEVEL=7
+#CFLAGS=-g -DDEBUG
+#CFLAGS=-O3 -Wall -Wwrite-strings -Wpointer-arith -Wconversion \
+#           -Wstrict-prototypes -Wmissing-prototypes
+
+LDFLAGS=-L. -lz
+LDSHARED=$(CC)
+
+VER=1.0
+LIBS=libz.a
+
+AR=ar rc
+RANLIB=ranlib
+TAR=tar
+
+prefix=/usr/local
+exec_prefix = $(prefix)
+
+OBJS = adler32.o compress.o crc32.o gzio.o uncompr.o deflate.o trees.o \
+       zutil.o inflate.o infblock.o inftrees.o infcodes.o infutil.o inffast.o
+
+TEST_OBJS = example.o minigzip.o
+
+DISTFILES = README ChangeLog configure Makefile.in Makefile Makefile.msc \
+	    Makefile.bor Makefile.tc Make_vms.com descrip.mms *.[ch]
+
+all: example minigzip
+
+test: all
+	./example
+	echo hello world | ./minigzip | ./minigzip -d 
+
+libz.a: $(OBJS)
+	$(AR) $@ $(OBJS)
+	-@ ($(RANLIB) $@ || true) 2>/dev/null
+
+libz.so.$(VER): $(OBJS)
+	$(LDSHARED) -o $@ $(OBJS)
+	rm -f libz.so; ln -s $@ libz.so
+
+example: example.o $(LIBS)
+	$(CC) $(CFLAGS) -o $@ example.o $(LDFLAGS)
+
+minigzip: minigzip.o $(LIBS)
+	$(CC) $(CFLAGS) -o $@ minigzip.o $(LDFLAGS)
+
+install: $(LIBS)
+	-@if [ ! $(prefix)/include  ]; then mkdir $(prefix)/include; fi
+	-@if [ ! $(exec_prefix)/lib ]; then mkdir $(exec_prefix)/lib; fi
+	cp zlib.h zconf.h $(prefix)/include
+	chmod 644 $(prefix)/include/zlib.h $(prefix)/include/zconf.h
+	cp $(LIBS) $(exec_prefix)/lib
+	cd $(exec_prefix)/lib; chmod 644 $(LIBS)
+	-@(cd $(exec_prefix)/lib; $(RANLIB) libz.a || true) >/dev/null 2>&1
+	cd $(exec_prefix)/lib; if test -f libz.so.$(VER); then \
+	  ln -s libz.so.$(VER) libz.so; \
+	fi
+# The ranlib in install is needed on NeXTSTEP which checks file times
+
+uninstall:
+	cd $(exec_prefix)/lib; rm -f $(LIBS); \
+	if test -f libz.so; then \
+	 v=`sed -n '/VERSION "/s/.*"\(.*\)".*/\1/p'<$(prefix)/include/zlib.h`;\
+	 rm -f libz.so.$$v libz.so; \
+	fi
+	cd $(prefix)/include; rm -f zlib.h zconf.h
+
+clean:
+	rm -f *.o *~ example minigzip libz.a libz.so* foo.gz
+
+zip:
+	mv Makefile Makefile~; cp -p Makefile.in Makefile
+	v=`sed -n -e 's/\./-/' -e '/VERSION "/s/.*"\(.*\)".*/\1/p' < zlib.h`;\
+	zip -ul9 zlib-$$v $(DISTFILES)
+	mv Makefile~ Makefile
+
+dist:
+	mv Makefile Makefile~; cp -p Makefile.in Makefile
+	d=zlib-`sed -n '/VERSION "/s/.*"\(.*\)".*/\1/p' < zlib.h`;\
+	rm -f $$d.tar.gz; \
+	if test ! -d ../$$d; then rm -f ../$$d; ln -s `pwd` ../$$d; fi; \
+	files=""; \
+	for f in $(DISTFILES); do files="$$files $$d/$$f"; done; \
+	cd ..; \
+	GZIP=-9 $(TAR) chofz $$d/$$d.tar.gz $$files; \
+	if test ! -d $$d; then rm -f $$d; fi
+	mv Makefile~ Makefile
+
+tags:	
+	etags *.[ch]
+
+depend:
+	makedepend -- $(CFLAGS) -- *.[ch]
+
+# DO NOT DELETE THIS LINE -- make depend depends on it.
+
+adler32.o: zlib.h zconf.h
+compress.o: zlib.h zconf.h
+crc32.o: zlib.h zconf.h
+deflate.o: deflate.h zutil.h zlib.h zconf.h
+example.o: zlib.h zconf.h
+gzio.o: zutil.h zlib.h zconf.h
+infblock.o: infblock.h inftrees.h infcodes.h infutil.h zutil.h zlib.h zconf.h
+infcodes.o: zutil.h zlib.h zconf.h
+infcodes.o: inftrees.h infblock.h infcodes.h infutil.h inffast.h
+inffast.o: zutil.h zlib.h zconf.h inftrees.h
+inffast.o: infblock.h infcodes.h infutil.h inffast.h
+inflate.o: zutil.h zlib.h zconf.h infblock.h
+inftrees.o: zutil.h zlib.h zconf.h inftrees.h
+infutil.o: zutil.h zlib.h zconf.h infblock.h inftrees.h infcodes.h infutil.h
+minigzip.o:  zlib.h zconf.h 
+trees.o: deflate.h zutil.h zlib.h zconf.h 
+uncompr.o: zlib.h zconf.h
+zutil.o: zutil.h zlib.h zconf.h  
--- a/Makefile.qnx
+++ b/Makefile.qnx
@@ -1,75 +0,0 @@
-# Makefile for zlib
-# Copyright (C) 1995 Jean-loup Gailly.
-# For conditions of distribution and use, see copyright notice in zlib.h 
-
-# Modified slightly for QNX by Chris Herborth (chrish@qnx.com)
-
-CC=cc
-CFLAGS=-4 -O -Q
-#use -O3 for gcc to take advantage of inlining
-#CFLAGS="-O -DMAX_WBITS=14 -DMAX_MEM_LEVEL=7"
-#CFLAGS=-g -DDEBUG
-LDFLAGS=-L. -lz
-
-#RANLIB=ranlib
-
-prefix=/usr/local
-
-OBJS = adler32.o compress.o crc32.o gzio.o uncompr.o deflate.o trees.o \
-       zutil.o inflate.o infblock.o inftrees.o infcodes.o infutil.o inffast.o
-
-TEST_OBJS = example.o minigzip.o
-
-all: example minigzip
-
-test: all
-	./example
-	echo hello world | ./minigzip | ./minigzip -d 
-
-install: zlib.lib
-	-@mkdir $(prefix)/include
-	-@mkdir $(prefix)/lib
-	cp zlib.h zconf.h $(prefix)/include
-	chmod 644 $(prefix)/include/zlib.h $(prefix)/include/zconf.h
-	cp zlib.lib $(prefix)/lib
-	chmod 644 $(prefix)/lib/zlib.lib
-
-zlib.lib: $(OBJS)
-	cc -A $@ $(OBJS)
-#	ar rc $@ $(OBJS)
-#	$(RANLIB) $@
-
-example: example.o zlib.lib
-	$(CC) $(CFLAGS) -o $@ example.o $(LDFLAGS)
-
-minigzip: minigzip.o zlib.lib
-	$(CC) $(CFLAGS) -o $@ minigzip.o $(LDFLAGS)
-
-clean:
-	rm -f *.o example minigzip zlib.lib foo.gz
-
-zip:
-	zip -ul9 zlib README ChangeLog Makefile Makefile.??? Makefile.?? *.[ch]
-
-tgz:
-	cd ..; tar cfz zlib/zlib.tgz zlib/README zlib/ChangeLog zlib/Makefile \
-		zlib/Makefile.??? zlib/Makefile.?? zlib/*.[ch]
-
-# DO NOT DELETE THIS LINE -- make depend depends on it.
-
-adler32.o: zutil.h zlib.h zconf.h
-compress.o: zlib.h zconf.h
-crc32.o: zutil.h zlib.h zconf.h
-deflate.o: deflate.h zutil.h zlib.h zconf.h
-example.o: zlib.h zconf.h
-gzio.o: zutil.h zlib.h zconf.h
-infblock.o: zutil.h zlib.h zconf.h infblock.h inftrees.h infcodes.h infutil.h
-infcodes.o: zutil.h zlib.h zconf.h inftrees.h infutil.h infcodes.h inffast.h
-inffast.o: zutil.h zlib.h zconf.h inftrees.h infutil.h inffast.h
-inflate.o: zutil.h zlib.h zconf.h infblock.h
-inftrees.o: zutil.h zlib.h zconf.h inftrees.h
-infutil.o: zutil.h zlib.h zconf.h inftrees.h infutil.h
-minigzip.o: zlib.h zconf.h
-trees.o: deflate.h zutil.h zlib.h zconf.h
-uncompr.o: zlib.h zconf.h
-zutil.o: zutil.h zlib.h zconf.h
--- a/91
+++ b/91
@@ -1,40 +1,75 @@
-zlib 0.95 is a beta version of a general purpose compression library.
-This should be the last version before the first official
-version (1.0), so please test it now. (At least compile and run it with
-"make test"). This version has no known bugs.
-
-The data format used by the zlib library is described in the
-files zlib-3.1.doc, deflate-1.1.doc and gzip-4.1.doc, available
-in ftp.uu.net:/pub/archiving/zip/doc.
+zlib 1.0 is a general purpose data compression library.  All the code
+is reentrant (thread safe).  The data format used by the zlib library
+is described in the files zlib-3.3.doc, deflate-1.3.doc and
+gzip-4.3.doc, available in ftp://ftp.uu.net/pub/archiving/zip/doc/

 All functions of the compression library are documented in the file
 zlib.h. A usage example of the library is given in the file example.c
 which also tests that the library is working correctly. Another
-example is given in the file minigzip.c.
+example is given in the file minigzip.c. The compression library itself
+is composed of all source files except example.c and minigzip.c.

-To compile all files and run the test program, just type: make test
-(For MSDOS, use one of the special makefiles such as Makefile.msc;
-for VMS, use Make_vms.com or descrip.mms.)
-To install the zlib library (libz.a) in /usr/local/lib, type: make install
-To install in a different directory, use for example:
-  make install prefix=$HOME
-This will install in $HOME/lib instead of /usr/local/lib.
+To compile all files and run the test program, follow the instructions
+given at the top of Makefile. In short "make test; make install"
+should work for most machines.  For MSDOS, use one of the special
+makefiles such as Makefile.msc; for VMS, use Make_vms.com or descrip.mms.

-The changes made in version 0.95 are documented in the file ChangeLog.
-The main changes since 0.94 are:
- fix MSDOS small and medium model (now easier to adapt to any compiler)
- inlined send_bits
- fix the final (:-) bug for deflate with flush (output was correct but
-  not completely flushed in rare occasions).
+Questions about zlib should be sent to <zlib@quest.jpl.nasa.gov> or,
+if this fails, to the addresses given below in the Copyright section.

-For MSDOS, the small and medium models have been tested only with Microsoft C.
-(This should now work for Borland C also, but I don't have a recent Borland
-compiler to test with.) The small model was tested with Turbo C but only with
-reduced performance to avoid any far allocation; it was tested with
- -DMAX_WBITS=11 -DMAX_MEM_LEVEL=3
+The changes made in version 1.0 are documented in the file ChangeLog.
+The main changes since 0.95 are:
+- allow preset dictionary shared between compressor and decompressor
+- allow compression level 0 (no compression)
+- add deflateParams in zlib.h: allow dynamic change of compression level
+  and compression strategy.
+- test large buffers and deflateParams in example.c
+- add optional "configure" to build zlib as a shared library
+- suppress Makefile.qnx, use configure instead
+- fixes for 64-bit systems (needed for Alpha and Cray)
+- declare Z_DEFLATED in zlib.h (possible parameter for deflateInit2)
+- always return Z_BUF_ERROR when deflate() has nothing to do
+- deflateInit and inflateInit are now macros to allow version checking
+- prefix all global functions and types with z_ with -DZ_PREFIX
+- fix some very unlikely race conditions in multi-threaded environment
+- several minor fixes for better portability
+- free in reverse order of allocation to help memory manager
+- use zlib-1.0/* instead of zlib/* inside the tar.gz
+- make zlib warning-free with "gcc -O3 -Wall -Wwrite-strings -Wpointer-arith
+  -Wconversion -Wstrict-prototypes -Wmissing-prototypes"
+- allow gzread on concatenated .gz files
+- deflateEnd now returns Z_DATA_ERROR if it was premature
+- deflate is finally (?) fully deterministic

+Notes for some targets:

- (C) 1995 Jean-loup Gailly and Mark Adler
+- For Turbo C the small model is supported only with reduced performance to
+  avoid any far allocation; it was tested with -DMAX_WBITS=11 -DMAX_MEM_LEVEL=3
+
+- For 64-bit Iris, deflate.c must be compiled without any optimization.
+  With -O, one libpng test fails. The test works in 32 bit mode (with the
+  -32 compiler flag).
+
+- zlib doesn't work with gcc 2.6.3 on a DEC 3000/300LX under OSF/1 2.1   
+  it works when compiled with cc.
+
+- zlib doesn't work on HP-UX 9.05 with one cc compiler (the one not
+  accepting the -O option). It works with the other cc compiler.
+
+A Perl interface to zlib written by Paul Marquess <pmarquess@bfsec.bt.co.uk>
+is in the CPAN (Comprehensive Perl Archive Network) sites, such as:
+ftp://ftp.cis.ufl.edu/pub/perl/CPAN/modules/by-module/Compress/Compress-Zlib*
+
+Acknowledgments:
+
+  The deflate format used by zlib was defined by Phil Katz. The deflate
+  and zlib specifications were written by Peter Deutsch. Thanks to all the
+  people who reported problems and suggested various improvements in zlib;
+  they are too numerous to cite here.
+
+Copyright notice:
+
+ (C) 1995-1996 Jean-loup Gailly and Mark Adler

  This software is provided 'as-is', without any express or implied
  warranty.  In no event will the authors be held liable for any damages
--- a/adler32.c
+++ b/adler32.c
@@ -1,5 +1,5 @@
 /* adler32.c -- compute the Adler-32 checksum of a data stream
- * Copyright (C) 1995 Mark Adler
+ * Copyright (C) 1995-1996 Mark Adler
 * For conditions of distribution and use, see copyright notice in zlib.h 
 */

@@ -20,7 +20,7 @@
 /* ========================================================================= */
 uLong adler32(adler, buf, len)
    uLong adler;
-    Bytef *buf;
+    const Bytef *buf;
    uInt len;
 {
    unsigned long s1 = adler & 0xffff;
--- a/compress.c
+++ b/compress.c
@@ -1,5 +1,5 @@
 /* compress.c -- compress a memory buffer
- * Copyright (C) 1995 Jean-loup Gailly.
+ * Copyright (C) 1995-1996 Jean-loup Gailly.
 * For conditions of distribution and use, see copyright notice in zlib.h 
 */

@@ -22,13 +22,13 @@
 int compress (dest, destLen, source, sourceLen)
    Bytef *dest;
    uLongf *destLen;
-    Bytef *source;
+    const Bytef *source;
    uLong sourceLen;
 {
    z_stream stream;
    int err;

-    stream.next_in = source;
+    stream.next_in = (Bytef*)source;
    stream.avail_in = (uInt)sourceLen;
    /* Check for source > 64K on 16-bit machine: */
    if ((uLong)stream.avail_in != sourceLen) return Z_BUF_ERROR;
@@ -39,6 +39,7 @@ int compress (dest, destLen, source, sourceLen)

    stream.zalloc = (alloc_func)0;
    stream.zfree = (free_func)0;
+    stream.opaque = (voidpf)0;

    err = deflateInit(&stream, Z_DEFAULT_COMPRESSION);
    if (err != Z_OK) return err;
--- a/81
+++ b/81
@@ -0,0 +1,81 @@
+#!/bin/sh
+# configure script for zlib. This script is needed only if
+# you wish to build a shared library and your system supports them,
+# of if you need special compiler, flags or install directory.
+# Otherwise, you can just use directly "make test; make install"
+#
+# To impose specific compiler or flags or install directory, use for example:
+#    prefix=$HOME CC=cc CFLAGS="-O4" ./configure
+# or for csh/tcsh users:
+#    (setenv prefix $HOME; setenv CC cc; setenv CFLAGS "-O4"; ./configure)
+# LDSHARED is the command to be used to create a shared library
+
+LIBS=libz.a
+VER=`sed -n -e '/VERSION "/s/.*"\(.*\)".*/\1/p' < zlib.h`
+AR=${AR-"ar rc"}
+prefix=${prefix-/usr/local}
+exec_prefix=${exec_prefix-$prefix}
+
+test -z "$CC" && echo Checking for gcc...
+test=ztest$$
+cat > $test.c <<EOF
+int hello() { printf("hello\n"); }
+EOF
+if test -z "$CC" && (gcc -c -O3 $test.c) 2>/dev/null; then
+  CC=gcc
+  SFLAGS=${CFLAGS-"-fPIC -O3"}
+  CFLAGS=${CFLAGS-"-O3"}
+  LDSHARED=${LDSHARED-"gcc -shared"}
+else
+  # find system name and corresponding cc options
+  CC=${CC-cc}
+  case `(uname -sr || echo unknown) 2>/dev/null` in
+  SunOS\ 5*) SFLAGS=${CFLAGS-"-fast -xcg89 -KPIC -R."}
+             CFLAGS=${CFLAGS-"-fast -xcg89"}
+	     LDSHARED=${LDSHARED-"cc -G"};;
+  SunOS\ 4*) SFLAGS=${CFLAGS-"-O2 -PIC"}
+	     CFLAGS=${CFLAGS-"-O2"}
+	     LDSHARED=${LDSHARED-"ld"};;
+  IRIX*)     SFLAGS=${CFLAGS-"-O2 -rpath ."}
+	     CFLAGS=${CFLAGS-"-O2"}
+	     LDSHARED=${LDSHARED-"cc -shared"};;
+  QNX*)      SFLAGS=${CFLAGS-"-4 -O -Q"}
+             CFLAGS=${CFLAGS-"-4 -O -Q"}
+	     LDSHARED=${LDSHARED-"cc"}
+             LIBS=zlib.lib
+             AR="cc -A";;
+  # send working options for other systems to gzip@prep.ai.mit.edu
+  *)         SFLAGS=${CFLAGS-"-O"}
+	     CFLAGS=${CFLAGS-"-O"}
+	     LDSHARED=${LDSHARED-"-shared"};;
+  esac
+fi
+
+echo Checking for shared library support...
+# we must test in two steps (cc then ld), required at least on SunOS 4.x
+if test "`$CC -c $SFLAGS $test.c 2>&1`" = "" &&
+   test "`$LDSHARED -o $test.so $test.o 2>&1`" = ""; then
+  CFLAGS="$SFLAGS"
+  LIBS='libz.so.$(VER)'
+  echo Building shared library libz.so.$VER with $CC.
+else
+  LDSHARED="$CC"
+  echo Building static library $LIBS version $VER with $CC.
+fi
+rm -f $test.[co] $test.so
+
+# udpate Makefile
+# ed -s Makefile <<EOF
+sed < Makefile.in "
+/^CC *=/s/=.*/=$CC/
+/^CFLAGS *=/s/=.*/=$CFLAGS/
+/^LDSHARED *=/s/=.*/=$LDSHARED/
+/^LIBS *=/s,=.*,=$LIBS,
+/^AR *=/s/=.*/=$AR/
+/^VER *=/s/=.*/=$VER/
+/^prefix *=/s,=.*,=$prefix,
+/^exec_prefix *=/s,=.*,=$exec_prefix,
+" > Makefile
+#w
+#q
+#EOF
--- a/crc32.c
+++ b/crc32.c
@@ -1,5 +1,5 @@
 /* crc32.c -- compute the CRC-32 of a data stream
- * Copyright (C) 1995 Mark Adler
+ * Copyright (C) 1995-1996 Mark Adler
 * For conditions of distribution and use, see copyright notice in zlib.h 
 */

@@ -10,23 +10,53 @@
 #define local static

 #ifdef DYNAMIC_CRC_TABLE
-/* =========================================================================
- * Make the crc table. This function is needed only if you want to compute
- * the table dynamically.
- */
-local int crc_table_empty = 1;
-local uLong crc_table[256];

+local int crc_table_empty = 1;
+local uLongf crc_table[256];
+local void make_crc_table OF((void));
+
+/*
+  Generate a table for a byte-wise 32-bit CRC calculation on the polynomial:
+  x^32+x^26+x^23+x^22+x^16+x^12+x^11+x^10+x^8+x^7+x^5+x^4+x^2+x+1.
+
+  Polynomials over GF(2) are represented in binary, one bit per coefficient,
+  with the lowest powers in the most significant bit.  Then adding polynomials
+  is just exclusive-or, and multiplying a polynomial by x is a right shift by
+  one.  If we call the above polynomial p, and represent a byte as the
+  polynomial q, also with the lowest power in the most significant bit (so the
+  byte 0xb1 is the polynomial x^7+x^3+x+1), then the CRC is (q*x^32) mod p,
+  where a mod b means the remainder after dividing a by b.
+
+  This calculation is done using the shift-register method of multiplying and
+  taking the remainder.  The register is initialized to zero, and for each
+  incoming bit, x^32 is added mod p to the register if the bit is a one (where
+  x^32 mod p is p+x^32 = x^26+...+1), and the register is multiplied mod p by
+  x (which is shifting right by one and adding x^32 mod p if the bit shifted
+  out is a one).  We start with the highest power (least significant bit) of
+  q and repeat for all eight bits of q.
+
+  The table is simply the CRC of all possible eight bit values.  This is all
+  the information needed to generate CRC's on data a byte at a time for all
+  combinations of CRC register values and incoming bytes.
+*/
 local void make_crc_table()
 {
  uLong c;
  int n, k;
+  uLong poly;            /* polynomial exclusive-or pattern */
+  /* terms of polynomial defining this crc (except x^32): */
+  static Byte p[] = {0,1,2,4,5,7,8,10,11,12,16,22,23,26};
+
+  /* make exclusive-or pattern from polynomial (0xedb88320L) */
+  poly = 0L;
+  for (n = 0; n < sizeof(p)/sizeof(Byte); n++)
+    poly |= 1L << (31 - p[n]);
 
  for (n = 0; n < 256; n++)
  {
    c = (uLong)n;
    for (k = 0; k < 8; k++)
-      c = c & 1 ? 0xedb88320L ^ (c >> 1) : c >> 1;
+      c = c & 1 ? poly ^ (c >> 1) : c >> 1;
    crc_table[n] = c;
  }
  crc_table_empty = 0;
@@ -35,7 +65,7 @@ local void make_crc_table()
 /* ========================================================================
 * Table of CRC-32's of all single-byte values (made by make_crc_table)
 */
-local uLong crc_table[] = {
+local uLongf crc_table[256] = {
  0x00000000L, 0x77073096L, 0xee0e612cL, 0x990951baL, 0x076dc419L,
  0x706af48fL, 0xe963a535L, 0x9e6495a3L, 0x0edb8832L, 0x79dcb8a4L,
  0xe0d5e91eL, 0x97d2d988L, 0x09b64c2bL, 0x7eb17cbdL, 0xe7b82d07L,
@@ -91,6 +121,18 @@ local uLong crc_table[] = {
 };
 #endif

+/* =========================================================================
+ * This function can be used by asm versions of crc32()
+ */
+uLongf *get_crc_table()
+{
+#ifdef DYNAMIC_CRC_TABLE
+  if (crc_table_empty) make_crc_table();
+#endif
+  return (uLongf *)crc_table;
+}
+
+/* ========================================================================= */
 #define DO1(buf) crc = crc_table[((int)crc ^ (*buf++)) & 0xff] ^ (crc >> 8);
 #define DO2(buf)  DO1(buf); DO1(buf);
 #define DO4(buf)  DO2(buf); DO2(buf);
@@ -99,7 +141,7 @@ local uLong crc_table[] = {
 /* ========================================================================= */
 uLong crc32(crc, buf, len)
    uLong crc;
-    Bytef *buf;
+    const Bytef *buf;
    uInt len;
 {
    if (buf == Z_NULL) return 0L;
--- a/deflate.c
+++ b/deflate.c
@@ -1,5 +1,5 @@
 /* deflate.c -- compress data using the deflation algorithm
- * Copyright (C) 1995 Jean-loup Gailly.
+ * Copyright (C) 1995-1996 Jean-loup Gailly.
 * For conditions of distribution and use, see copyright notice in zlib.h 
 */

@@ -51,7 +51,7 @@

 #include "deflate.h"

-char copyright[] = " deflate Copyright 1995 Jean-loup Gailly ";
+char deflate_copyright[] = " deflate 1.0 Copyright 1995-1996 Jean-loup Gailly ";
 /*
  If you use the zlib library in a product, an acknowledgment is welcome
  in the documentation of your product. If for some reason you cannot
@@ -59,6 +59,31 @@ char copyright[] = " deflate Copyright 1995 Jean-loup Gailly ";
  copyright string in the executable of your product.
 */

+/* ===========================================================================
+ *  Function prototypes.
+ */
+local void fill_window    OF((deflate_state *s));
+local int  deflate_stored OF((deflate_state *s, int flush));
+local int  deflate_fast   OF((deflate_state *s, int flush));
+local int  deflate_slow   OF((deflate_state *s, int flush));
+local void lm_init        OF((deflate_state *s));
+local int longest_match   OF((deflate_state *s, IPos cur_match));
+local void putShortMSB    OF((deflate_state *s, uInt b));
+local void flush_pending  OF((z_stream *strm));
+local int read_buf        OF((z_stream *strm, charf *buf, unsigned size));
+#ifdef ASMV
+      void match_init OF((void)); /* asm code initialization */
+#endif
+
+#ifdef DEBUG
+local  void check_match OF((deflate_state *s, IPos start, IPos match,
+                            int length));
+#endif
+
+/* ===========================================================================
+ * Local data
+ */
+
 #define NIL 0
 /* Tail of hash chains */

@@ -72,32 +97,35 @@ char copyright[] = " deflate Copyright 1995 Jean-loup Gailly ";
 * See deflate.c for comments about the MIN_MATCH+1.
 */

+typedef int (*compress_func) OF((deflate_state *s, int flush));
+/* Compressing function */
+
 /* Values for max_lazy_match, good_match and max_chain_length, depending on
 * the desired pack level (0..9). The values given below have been tuned to
 * exclude worst case performance for pathological files. Better values may be
 * found for specific files.
 */
-
 typedef struct config_s {
   ush good_length; /* reduce lazy search above this match length */
   ush max_lazy;    /* do not perform lazy search above this match length */
   ush nice_length; /* quit search above this match length */
   ush max_chain;
+   compress_func func;
 } config;

 local config configuration_table[10] = {
 /*      good lazy nice chain */
-/* 0 */ {0,    0,  0,    0},  /* store only */
-/* 1 */ {4,    4,  8,    4},  /* maximum speed, no lazy matches */
-/* 2 */ {4,    5, 16,    8},
-/* 3 */ {4,    6, 32,   32},
+/* 0 */ {0,    0,  0,    0, deflate_stored},  /* store only */
+/* 1 */ {4,    4,  8,    4, deflate_fast}, /* maximum speed, no lazy matches */
+/* 2 */ {4,    5, 16,    8, deflate_fast},
+/* 3 */ {4,    6, 32,   32, deflate_fast},

-/* 4 */ {4,    4, 16,   16},  /* lazy matches */
-/* 5 */ {8,   16, 32,   32},
-/* 6 */ {8,   16, 128, 128},
-/* 7 */ {8,   32, 128, 256},
-/* 8 */ {32, 128, 258, 1024},
-/* 9 */ {32, 258, 258, 4096}}; /* maximum compression */
+/* 4 */ {4,    4, 16,   16, deflate_slow},  /* lazy matches */
+/* 5 */ {8,   16, 32,   32, deflate_slow},
+/* 6 */ {8,   16, 128, 128, deflate_slow},
+/* 7 */ {8,   32, 128, 256, deflate_slow},
+/* 8 */ {32, 128, 258, 1024, deflate_slow},
+/* 9 */ {32, 258, 258, 4096, deflate_slow}}; /* maximum compression */

 /* Note: the deflate() code requires max_lazy >= MIN_MATCH and max_chain >= 4
 * For deflate_fast() (levels <= 3) good is ignored and lazy has a different
@@ -109,28 +137,6 @@ local config configuration_table[10] = {

 struct static_tree_desc_s {int dummy;}; /* for buggy compilers */

-/* ===========================================================================
- *  Prototypes for local functions.
- */
-
-local void fill_window   OF((deflate_state *s));
-local int  deflate_fast  OF((deflate_state *s, int flush));
-local int  deflate_slow  OF((deflate_state *s, int flush));
-local void lm_init       OF((deflate_state *s));
-local int longest_match  OF((deflate_state *s, IPos cur_match));
-local void putShortMSB   OF((deflate_state *s, uInt b));
-local void flush_pending OF((z_stream *strm));
-local int read_buf       OF((z_stream *strm, charf *buf, unsigned size));
-#ifdef ASMV
-      void match_init OF((void)); /* asm code initialization */
-#endif
-
-#ifdef DEBUG
-local  void check_match OF((deflate_state *s, IPos start, IPos match,
-                            int length));
-#endif
-
-
 /* ===========================================================================
 * Update a hash value with the given input byte
 * IN  assertion: all calls to to UPDATE_HASH are made with consecutive
@@ -162,30 +168,43 @@ local  void check_match OF((deflate_state *s, IPos start, IPos match,
    zmemzero((charf *)s->head, (unsigned)(s->hash_size-1)*sizeof(*s->head));

 /* ========================================================================= */
-int deflateInit (strm, level)
+int deflateInit_(strm, level, version, stream_size)
    z_stream *strm;
    int level;
+    const char *version;
+    int stream_size;
 {
-    return deflateInit2 (strm, level, DEFLATED, MAX_WBITS, DEF_MEM_LEVEL, 0);
+    return deflateInit2_(strm, level, Z_DEFLATED, MAX_WBITS, DEF_MEM_LEVEL,
+			 Z_DEFAULT_STRATEGY, version, stream_size);
    /* To do: ignore strm->next_in if we use it as window */
 }

 /* ========================================================================= */
-int deflateInit2 (strm, level, method, windowBits, memLevel, strategy)
+int deflateInit2_(strm, level, method, windowBits, memLevel, strategy,
+		  version, stream_size)
    z_stream *strm;
    int  level;
    int  method;
    int  windowBits;
    int  memLevel;
    int  strategy;
+    const char *version;
+    int stream_size;
 {
    deflate_state *s;
    int noheader = 0;

+    if (version == Z_NULL || version[0] != ZLIB_VERSION[0] ||
+        stream_size != sizeof(z_stream)) {
+	return Z_VERSION_ERROR;
+    }
    if (strm == Z_NULL) return Z_STREAM_ERROR;

    strm->msg = Z_NULL;
-    if (strm->zalloc == Z_NULL) strm->zalloc = zcalloc;
+    if (strm->zalloc == Z_NULL) {
+	strm->zalloc = zcalloc;
+	strm->opaque = (voidpf)0;
+    }
    if (strm->zfree == Z_NULL) strm->zfree = zcfree;

    if (level == Z_DEFAULT_COMPRESSION) level = 6;
@@ -194,8 +213,9 @@ int deflateInit2 (strm, level, method, windowBits, memLevel, strategy)
        noheader = 1;
        windowBits = -windowBits;
    }
-    if (memLevel < 1 || memLevel > MAX_MEM_LEVEL || method != DEFLATED ||
-        windowBits < 8 || windowBits > 15 || level < 1 || level > 9) {
+    if (memLevel < 1 || memLevel > MAX_MEM_LEVEL || method != Z_DEFLATED ||
+        windowBits < 8 || windowBits > 15 || level < 0 || level > 9 ||
+	strategy < 0 || strategy > Z_HUFFMAN_ONLY) {
        return Z_STREAM_ERROR;
    }
    s = (deflate_state *) ZALLOC(strm, 1, sizeof(deflate_state));
@@ -223,15 +243,15 @@ int deflateInit2 (strm, level, method, windowBits, memLevel, strategy)

    if (s->window == Z_NULL || s->prev == Z_NULL || s->head == Z_NULL ||
        s->pending_buf == Z_NULL) {
-        strm->msg = z_errmsg[1-Z_MEM_ERROR];
+        strm->msg = ERR_MSG(Z_MEM_ERROR);
        deflateEnd (strm);
        return Z_MEM_ERROR;
    }
-    s->d_buf = (ushf *) &(s->pending_buf[s->lit_bufsize]);
-    s->l_buf = (uchf *) &(s->pending_buf[3*s->lit_bufsize]);
+    s->l_buf = (uchf *) &(s->pending_buf[s->lit_bufsize]);
+    s->d_buf = (ushf *) &(s->pending_buf[2*s->lit_bufsize]);
    /* We overlay pending_buf and d_buf+l_buf. This works since the average
     * output size for (length,distance) codes is <= 32 bits (worst case
-     * is 15+15+13=33).
+     * is 15+15+13=33). d_buf is put last in case sizeof(short)>2.
     */

    s->level = level;
@@ -241,6 +261,44 @@ int deflateInit2 (strm, level, method, windowBits, memLevel, strategy)
    return deflateReset(strm);
 }

+/* ========================================================================= */
+int deflateSetDictionary (strm, dictionary, dictLength)
+    z_stream *strm;
+    const Bytef *dictionary;
+    uInt  dictLength;
+{
+    deflate_state *s;
+    uInt length = dictLength;
+    uInt n;
+    IPos hash_head;
+
+    if (strm == Z_NULL || strm->state == Z_NULL || dictionary == Z_NULL ||
+        strm->state->status != INIT_STATE) return Z_STREAM_ERROR;
+
+    s = strm->state;
+    strm->adler = adler32(strm->adler, dictionary, dictLength);
+
+    if (length < MIN_MATCH) return Z_OK;
+    if (length > MAX_DIST(s)) {
+	length = MAX_DIST(s);
+	dictionary += dictLength - length;
+    }
+    zmemcpy((charf *)s->window, dictionary, length);
+    s->strstart = length;
+    s->block_start = (long)length;
+
+    /* Insert all strings in the hash table (except for the last two bytes).
+     * s->lookahead stays null, so s->ins_h will be recomputed at the next
+     * call of fill_window.
+     */
+    s->ins_h = s->window[0];
+    UPDATE_HASH(s, s->ins_h, s->window[1]);
+    for (n = 0; n <= length - MIN_MATCH; n++) {
+	INSERT_STRING(s, n, hash_head);
+    }
+    return Z_OK;
+}
+
 /* ========================================================================= */
 int deflateReset (strm)
    z_stream *strm;
@@ -262,14 +320,52 @@ int deflateReset (strm)
        s->noheader = 0; /* was set to -1 by deflate(..., Z_FINISH); */
    }
    s->status = s->noheader ? BUSY_STATE : INIT_STATE;
-    s->adler = 1;
+    strm->adler = 1;
+    s->last_flush = Z_NO_FLUSH;

-    ct_init(s);
+    _tr_init(s);
    lm_init(s);

    return Z_OK;
 }

+/* ========================================================================= */
+int deflateParams(strm, level, strategy)
+    z_stream *strm;
+    int level;
+    int strategy;
+{
+    deflate_state *s;
+    compress_func func;
+
+    if (strm == Z_NULL || strm->state == Z_NULL) return Z_STREAM_ERROR;
+    s = strm->state;
+
+    if (level == Z_DEFAULT_COMPRESSION) {
+	level = 6;
+    }
+    if (level < 0 || level > 9 || strategy < 0 || strategy > Z_HUFFMAN_ONLY) {
+	return Z_STREAM_ERROR;
+    }
+    func = configuration_table[s->level].func;
+
+    if (func != configuration_table[level].func
+	&& strm->state->lookahead != 0) {
+
+	/* Flush the last buffer: */
+	(void)(*func)(strm->state, Z_PARTIAL_FLUSH);
+    }
+    if (s->level != level) {
+	s->level = level;
+	s->max_lazy_match   = configuration_table[level].max_lazy;
+	s->good_match       = configuration_table[level].good_length;
+	s->nice_match       = configuration_table[level].nice_length;
+	s->max_chain_length = configuration_table[level].max_chain;
+    }
+    s->strategy = strategy;
+    return Z_OK;
+}
+
 /* =========================================================================
 * Put a short in the pending buffer. The 16-bit value is put in MSB order.
 * IN assertion: the stream state is correct and there is enough room in
@@ -284,7 +380,10 @@ local void putShortMSB (s, b)
 }   

 /* =========================================================================
- * Flush as much pending output as possible.
+ * Flush as much pending output as possible. All deflate() output goes
+ * through this function so some applications may wish to modify it
+ * to avoid allocating a large strm->next_out buffer and copying into it.
+ * (See also read_buf()).
 */
 local void flush_pending(strm)
    z_stream *strm;
@@ -310,55 +409,76 @@ int deflate (strm, flush)
    z_stream *strm;
    int flush;
 {
+    int old_flush; /* value of flush param for previous deflate call */
+    deflate_state *s;
+
    if (strm == Z_NULL || strm->state == Z_NULL) return Z_STREAM_ERROR;
    
+    s = strm->state;
+
    if (strm->next_out == Z_NULL ||
-        (strm->next_in == Z_NULL && strm->avail_in != 0)) {
+        (strm->next_in == Z_NULL && strm->avail_in != 0) ||
+	(s->status == FINISH_STATE && flush != Z_FINISH)) {
        ERR_RETURN(strm, Z_STREAM_ERROR);
    }
    if (strm->avail_out == 0) ERR_RETURN(strm, Z_BUF_ERROR);

-    strm->state->strm = strm; /* just in case */
+    s->strm = strm; /* just in case */
+    old_flush = s->last_flush;
+    s->last_flush = flush;

    /* Write the zlib header */
-    if (strm->state->status == INIT_STATE) {
+    if (s->status == INIT_STATE) {

-        uInt header = (DEFLATED + ((strm->state->w_bits-8)<<4)) << 8;
-        uInt level_flags = (strm->state->level-1) >> 1;
+        uInt header = (Z_DEFLATED + ((s->w_bits-8)<<4)) << 8;
+        uInt level_flags = (s->level-1) >> 1;

        if (level_flags > 3) level_flags = 3;
        header |= (level_flags << 6);
+	if (s->strstart != 0) header |= PRESET_DICT;
        header += 31 - (header % 31);

-        strm->state->status = BUSY_STATE;
-        putShortMSB(strm->state, header);
+        s->status = BUSY_STATE;
+        putShortMSB(s, header);
+
+	/* Save the adler32 of the preset dictionary: */
+	if (s->strstart != 0) {
+	    putShortMSB(s, (uInt)(strm->adler >> 16));
+	    putShortMSB(s, (uInt)(strm->adler & 0xffff));
+	    strm->adler = 1L;
+	}
    }

    /* Flush as much pending output as possible */
-    if (strm->state->pending != 0) {
+    if (s->pending != 0) {
        flush_pending(strm);
        if (strm->avail_out == 0) return Z_OK;
+
+    /* Make sure there is something to do and avoid duplicate consecutive
+     * flushes. For repeated and useless calls with Z_FINISH, we keep
+     * returning Z_STREAM_END instead of Z_BUFF_ERROR.
+     */
+    } else if (strm->avail_in == 0 && flush <= old_flush &&
+	       flush != Z_FINISH) {
+        ERR_RETURN(strm, Z_BUF_ERROR);
    }

    /* User must not provide more input after the first FINISH: */
-    if (strm->state->status == FINISH_STATE && strm->avail_in != 0) {
+    if (s->status == FINISH_STATE && strm->avail_in != 0) {
        ERR_RETURN(strm, Z_BUF_ERROR);
    }

    /* Start a new block or continue the current one.
     */
-    if (strm->avail_in != 0 || strm->state->lookahead != 0 ||
-        (flush != Z_NO_FLUSH && strm->state->status != FINISH_STATE)) {
+    if (strm->avail_in != 0 || s->lookahead != 0 ||
+        (flush != Z_NO_FLUSH && s->status != FINISH_STATE)) {
        int quit;

        if (flush == Z_FINISH) {
-            strm->state->status = FINISH_STATE;
-        }
-        if (strm->state->level <= 3) {
-            quit = deflate_fast(strm->state, flush);
-        } else {
-            quit = deflate_slow(strm->state, flush);
+            s->status = FINISH_STATE;
        }
+	quit = (*(configuration_table[s->level].func))(s, flush);
+
        if (quit || strm->avail_out == 0) return Z_OK;
        /* If flush != Z_NO_FLUSH && avail_out == 0, the next call
         * of deflate should use the same flush parameter to make sure
@@ -367,16 +487,16 @@ int deflate (strm, flush)
         * ensures that for a very small output buffer, we emit at most
         * one empty block.
         */
-        if (flush != Z_OK && flush != Z_FINISH) {
+        if (flush != Z_NO_FLUSH && flush != Z_FINISH) {
            if (flush == Z_PARTIAL_FLUSH) {
-                ct_align(strm->state);
+                _tr_align(s);
            } else { /* FULL_FLUSH or SYNC_FLUSH */
-                ct_stored_block(strm->state, (char*)0, 0L, 0);
+                _tr_stored_block(s, (char*)0, 0L, 0);
                /* For a full flush, this empty block will be recognized
                 * as a special marker by inflate_sync().
                 */
                if (flush == Z_FULL_FLUSH) {
-                    CLEAR_HASH(strm->state);             /* forget history */
+                    CLEAR_HASH(s);             /* forget history */
                }
            }
            flush_pending(strm);
@@ -386,34 +506,38 @@ int deflate (strm, flush)
    Assert(strm->avail_out > 0, "bug2");

    if (flush != Z_FINISH) return Z_OK;
-    if (strm->state->noheader) return Z_STREAM_END;
+    if (s->noheader) return Z_STREAM_END;

    /* Write the zlib trailer (adler32) */
-    putShortMSB(strm->state, (uInt)(strm->state->adler >> 16));
-    putShortMSB(strm->state, (uInt)(strm->state->adler & 0xffff));
+    putShortMSB(s, (uInt)(strm->adler >> 16));
+    putShortMSB(s, (uInt)(strm->adler & 0xffff));
    flush_pending(strm);
    /* If avail_out is zero, the application will call deflate again
     * to flush the rest.
     */
-    strm->state->noheader = -1; /* write the trailer only once! */
-    return strm->state->pending != 0 ? Z_OK : Z_STREAM_END;
+    s->noheader = -1; /* write the trailer only once! */
+    return s->pending != 0 ? Z_OK : Z_STREAM_END;
 }

 /* ========================================================================= */
 int deflateEnd (strm)
    z_stream *strm;
 {
+    int status;
+
    if (strm == Z_NULL || strm->state == Z_NULL) return Z_STREAM_ERROR;

-    TRY_FREE(strm, strm->state->window);
-    TRY_FREE(strm, strm->state->prev);
-    TRY_FREE(strm, strm->state->head);
+    /* Deallocate in reverse order of allocations: */
    TRY_FREE(strm, strm->state->pending_buf);
+    TRY_FREE(strm, strm->state->head);
+    TRY_FREE(strm, strm->state->prev);
+    TRY_FREE(strm, strm->state->window);

+    status = strm->state->status;
    ZFREE(strm, strm->state);
    strm->state = Z_NULL;

-    return Z_OK;
+    return status == BUSY_STATE ? Z_DATA_ERROR : Z_OK;
 }

 /* ========================================================================= */
@@ -438,7 +562,10 @@ int deflateCopy (dest, source)

 /* ===========================================================================
 * Read a new buffer from the current input stream, update the adler32
- * and total number of bytes read.
+ * and total number of bytes read.  All deflate() input goes through
+ * this function so some applications may wish to modify it to avoid
+ * allocating a large strm->next_in buffer and copying from it.
+ * (See also flush_pending()).
 */
 local int read_buf(strm, buf, size)
    z_stream *strm;
@@ -453,7 +580,7 @@ local int read_buf(strm, buf, size)
    strm->avail_in  -= len;

    if (!strm->state->noheader) {
-        strm->state->adler = adler32(strm->state->adler, strm->next_in, len);
+        strm->adler = adler32(strm->adler, strm->next_in, len);
    }
    zmemcpy(buf, strm->next_in, len);
    strm->next_in  += len;
@@ -482,7 +609,7 @@ local void lm_init (s)
    s->strstart = 0;
    s->block_start = 0L;
    s->lookahead = 0;
-    s->match_length = MIN_MATCH-1;
+    s->match_length = s->prev_length = MIN_MATCH-1;
    s->match_available = 0;
    s->ins_h = 0;
 #ifdef ASMV
@@ -497,6 +624,7 @@ local void lm_init (s)
 * garbage.
 * IN assertions: cur_match is the head of the hash chain for the current
 *   string (strstart) and its distance is <= MAX_DIST, and prev_length >= 1
+ * OUT assertion: the match length is not greater than s->lookahead.
 */
 #ifndef ASMV
 /* For 80x86 and 680x0, an optimized version will be provided in match.asm or
@@ -511,6 +639,7 @@ local int longest_match(s, cur_match)
    register Bytef *match;                       /* matched string */
    register int len;                           /* length of current match */
    int best_len = s->prev_length;              /* best match length so far */
+    int nice_match = s->nice_match;             /* stop if match long enough */
    IPos limit = s->strstart > (IPos)MAX_DIST(s) ?
        s->strstart - (IPos)MAX_DIST(s) : NIL;
    /* Stop when cur_match becomes <= limit. To simplify the code,
@@ -541,6 +670,11 @@ local int longest_match(s, cur_match)
    if (s->prev_length >= s->good_match) {
        chain_length >>= 2;
    }
+    /* Do not look for matches beyond the end of the input. This is necessary
+     * to make deflate deterministic.
+     */
+    if (nice_match > s->lookahead) nice_match = s->lookahead;
+
    Assert((ulg)s->strstart <= s->window_size-MIN_LOOKAHEAD, "need lookahead");

    do {
@@ -619,7 +753,7 @@ local int longest_match(s, cur_match)
        if (len > best_len) {
            s->match_start = cur_match;
            best_len = len;
-            if (len >= s->nice_match) break;
+            if (len >= nice_match) break;
 #ifdef UNALIGNED_OK
            scan_end = *(ushf*)(scan+best_len-1);
 #else
@@ -630,7 +764,8 @@ local int longest_match(s, cur_match)
    } while ((cur_match = prev[cur_match & wmask]) > limit
             && --chain_length != 0);

-    return best_len;
+    if (best_len <= s->lookahead) return best_len;
+    return s->lookahead;
 }
 #endif /* ASMV */

@@ -644,13 +779,13 @@ local void check_match(s, start, match, length)
    int length;
 {
    /* check that the match is indeed a match */
-    if (memcmp((charf *)s->window + match,
+    if (zmemcmp((charf *)s->window + match,
                (charf *)s->window + start, length) != EQUAL) {
-        fprintf(stderr,
-            " start %u, match %u, length %d\n",
-            start, match, length);
-        do { fprintf(stderr, "%c%c", s->window[match++],
-                     s->window[start++]); } while (--length != 0);
+        fprintf(stderr, " start %u, match %u, length %d\n",
+		start, match, length);
+        do {
+	    fprintf(stderr, "%c%c", s->window[match++], s->window[start++]);
+	} while (--length != 0);
        z_error("invalid match");
    }
    if (verbose > 1) {
@@ -686,6 +821,7 @@ local void fill_window(s)
        /* Deal with !@#$% 64K limit: */
        if (more == 0 && s->strstart == 0 && s->lookahead == 0) {
            more = wsize;
+
        } else if (more == (unsigned)(-1)) {
            /* Very unlikely, but possible on 16 bit machine if strstart == 0
             * and lookahead == 1 (input done one byte at time)
@@ -697,9 +833,6 @@ local void fill_window(s)
         */
        } else if (s->strstart >= wsize+MAX_DIST(s)) {

-            /* By the IN assertion, the window is not empty so we can't confuse
-             * more == 0 with more == 64K on a 16 bit machine.
-             */
            zmemcpy((charf *)s->window, (charf *)s->window+wsize,
                   (unsigned)wsize);
            s->match_start -= wsize;
@@ -768,9 +901,11 @@ local void fill_window(s)
 * IN assertion: strstart is set to the end of the current match.
 */
 #define FLUSH_BLOCK_ONLY(s, eof) { \
-   ct_flush_block(s, (s->block_start >= 0L ? \
-               (charf *)&s->window[(unsigned)s->block_start] : \
-               (charf *)Z_NULL), (long)s->strstart - s->block_start, (eof)); \
+   _tr_flush_block(s, (s->block_start >= 0L ? \
+                   (charf *)&s->window[(unsigned)s->block_start] : \
+                   (charf *)Z_NULL), \
+		(ulg)((long)s->strstart - s->block_start), \
+		(eof)); \
   s->block_start = s->strstart; \
   flush_pending(s->strm); \
   Tracev((stderr,"[FLUSH]")); \
@@ -782,10 +917,55 @@ local void fill_window(s)
   if (s->strm->avail_out == 0) return 1; \
 }

+/* ===========================================================================
+ * Copy without compression as much as possible from the input stream, return
+ * true if processing was terminated prematurely (no more input or output
+ * space).  This function does not insert new strings in the dictionary
+ * since uncompressible data is probably not useful. This function is used
+ * only for the level=0 compression option.
+ * NOTE: this function should be optimized to avoid extra copying.
+ */
+local int deflate_stored(s, flush)
+    deflate_state *s;
+    int flush;
+{
+    for (;;) {
+        /* Fill the window as much as possible: */
+        if (s->lookahead <= 1) {
+
+            Assert(s->strstart < s->w_size+MAX_DIST(s) ||
+		   s->block_start >= (long)s->w_size, "slide too late");
+
+            fill_window(s);
+            if (s->lookahead == 0 && flush == Z_NO_FLUSH) return 1;
+
+            if (s->lookahead == 0) break; /* flush the current block */
+        }
+	Assert(s->block_start >= 0L, "block gone");
+
+	s->strstart += s->lookahead;
+	s->lookahead = 0;
+
+        /* Stored blocks are limited to 0xffff bytes: */
+        if (s->strstart == 0 || s->strstart > 0xffff) {
+	    /* strstart == 0 is possible when wraparound on 16-bit machine */
+	    s->lookahead = s->strstart - 0xffff;
+	    s->strstart = 0xffff;
+	}
+
+	/* Emit a stored block if it is large enough: */
+        if (s->strstart - (uInt)s->block_start >= MAX_DIST(s)) {
+            FLUSH_BLOCK(s, 0);
+	}
+    }
+    FLUSH_BLOCK(s, flush == Z_FINISH);
+    return 0; /* normal exit */
+}
+
 /* ===========================================================================
 * Compress as much as possible from the input stream, return true if
 * processing was terminated prematurely (no more input or output space).
- * This function does not perform lazy evaluationof matches and inserts
+ * This function does not perform lazy evaluation of matches and inserts
 * new strings in the dictionary only for unmatched strings or for short
 * matches. It is used only for the fast compression options.
 */
@@ -793,10 +973,8 @@ local int deflate_fast(s, flush)
    deflate_state *s;
    int flush;
 {
-    IPos hash_head; /* head of the hash chain */
-    int bflush;     /* set if current block must be flushed */
-
-    s->prev_length = MIN_MATCH-1;
+    IPos hash_head = NIL; /* head of the hash chain */
+    int bflush;           /* set if current block must be flushed */

    for (;;) {
        /* Make sure that we always have enough lookahead, except
@@ -830,14 +1008,12 @@ local int deflate_fast(s, flush)
                s->match_length = longest_match (s, hash_head);
            }
            /* longest_match() sets match_start */
-
-            if (s->match_length > s->lookahead) s->match_length = s->lookahead;
        }
        if (s->match_length >= MIN_MATCH) {
            check_match(s, s->strstart, s->match_start, s->match_length);

-            bflush = ct_tally(s, s->strstart - s->match_start,
-                              s->match_length - MIN_MATCH);
+            bflush = _tr_tally(s, s->strstart - s->match_start,
+                               s->match_length - MIN_MATCH);

            s->lookahead -= s->match_length;

@@ -870,7 +1046,7 @@ local int deflate_fast(s, flush)
        } else {
            /* No match, output a literal byte */
            Tracevv((stderr,"%c", s->window[s->strstart]));
-            bflush = ct_tally (s, 0, s->window[s->strstart]);
+            bflush = _tr_tally (s, 0, s->window[s->strstart]);
            s->lookahead--;
            s->strstart++; 
        }
@@ -889,7 +1065,7 @@ local int deflate_slow(s, flush)
    deflate_state *s;
    int flush;
 {
-    IPos hash_head;          /* head of hash chain */
+    IPos hash_head = NIL;    /* head of hash chain */
    int bflush;              /* set if current block must be flushed */

    /* Process the input block. */
@@ -928,7 +1104,6 @@ local int deflate_slow(s, flush)
                s->match_length = longest_match (s, hash_head);
            }
            /* longest_match() sets match_start */
-            if (s->match_length > s->lookahead) s->match_length = s->lookahead;

            if (s->match_length <= 5 && (s->strategy == Z_FILTERED ||
                 (s->match_length == MIN_MATCH &&
@@ -949,8 +1124,8 @@ local int deflate_slow(s, flush)

            check_match(s, s->strstart-1, s->prev_match, s->prev_length);

-            bflush = ct_tally(s, s->strstart -1 - s->prev_match,
-                              s->prev_length - MIN_MATCH);
+            bflush = _tr_tally(s, s->strstart -1 - s->prev_match,
+                               s->prev_length - MIN_MATCH);

            /* Insert in hash table all strings up to the end of the match.
             * strstart-1 and strstart are already inserted. If there is not
@@ -976,7 +1151,7 @@ local int deflate_slow(s, flush)
             * is longer, truncate the previous match to a single literal.
             */
            Tracevv((stderr,"%c", s->window[s->strstart-1]));
-            if (ct_tally (s, 0, s->window[s->strstart-1])) {
+            if (_tr_tally (s, 0, s->window[s->strstart-1])) {
                FLUSH_BLOCK_ONLY(s, 0);
            }
            s->strstart++;
@@ -994,7 +1169,7 @@ local int deflate_slow(s, flush)
    Assert (flush != Z_NO_FLUSH, "no flush?");
    if (s->match_available) {
        Tracevv((stderr,"%c", s->window[s->strstart-1]));
-        ct_tally (s, 0, s->window[s->strstart-1]);
+        _tr_tally (s, 0, s->window[s->strstart-1]);
        s->match_available = 0;
    }
    FLUSH_BLOCK(s, flush == Z_FINISH);
--- a/deflate.h
+++ b/deflate.h
@@ -1,5 +1,5 @@
 /* deflate.h -- internal compression state
- * Copyright (C) 1995 Jean-loup Gailly
+ * Copyright (C) 1995-1996 Jean-loup Gailly
 * For conditions of distribution and use, see copyright notice in zlib.h 
 */

@@ -10,17 +10,15 @@

 /* $Id: deflate.h,v 1.5 1995/05/03 17:27:09 jloup Exp $ */

+#ifndef _DEFLATE_H
+#define _DEFLATE_H
+
 #include "zutil.h"

 /* ===========================================================================
 * Internal compression state.
 */

-/* Data type */
-#define BINARY  0
-#define ASCII   1
-#define UNKNOWN 2
-
 #define LENGTH_CODES 29
 /* number of length codes, not counting the special END_BLOCK code */

@@ -87,10 +85,10 @@ typedef struct internal_state {
    Bytef *pending_buf;  /* output still pending */
    Bytef *pending_out;  /* next pending byte to output to the stream */
    int   pending;       /* nb of bytes in the pending buffer */
-    uLong adler;         /* adler32 of uncompressed data */
    int   noheader;      /* suppress zlib header and adler32 */
    Byte  data_type;     /* UNKNOWN, BINARY or ASCII */
    Byte  method;        /* STORED (for zip only) or DEFLATED */
+    int   last_flush;    /* value of flush param for previous deflate call */

                /* used by deflate.c: */

@@ -173,7 +171,7 @@ typedef struct internal_state {
    uInt good_match;
    /* Use a faster search when the previous match is longer than this */

-     int nice_match; /* Stop searching when current match exceeds this */
+    int nice_match; /* Stop searching when current match exceeds this */

                /* used by trees.c: */
    /* Didn't use ct_data typedef below to supress compiler warning */
@@ -267,9 +265,11 @@ typedef struct internal_state {
 */

        /* in trees.c */
-void ct_init       OF((deflate_state *s));
-int  ct_tally      OF((deflate_state *s, int dist, int lc));
-ulg ct_flush_block OF((deflate_state *s, charf *buf, ulg stored_len, int eof));
-void ct_align      OF((deflate_state *s));
-void ct_stored_block OF((deflate_state *s, charf *buf, ulg stored_len,
+void _tr_init         OF((deflate_state *s));
+int  _tr_tally        OF((deflate_state *s, unsigned dist, unsigned lc));
+ulg  _tr_flush_block  OF((deflate_state *s, charf *buf, ulg stored_len,
+			  int eof));
+void _tr_align        OF((deflate_state *s));
+void _tr_stored_block OF((deflate_state *s, charf *buf, ulg stored_len,
                          int eof));
+#endif
--- a/example.c
+++ b/example.c
@@ -1,5 +1,5 @@
 /* example.c -- usage example of the zlib compression library
- * Copyright (C) 1995 Jean-loup Gailly.
+ * Copyright (C) 1995-1996 Jean-loup Gailly.
 * For conditions of distribution and use, see copyright notice in zlib.h 
 */

@@ -10,20 +10,11 @@

 #ifdef STDC
 #  include <string.h>
+#  include <stdlib.h>
+#else
+   extern void exit  OF((int));
 #endif

-#ifndef __GO32__
-extern void exit  OF((int));
-#endif
-
-#define BUFLEN 4096
-
-#define local static
-/* For MSDOS and other systems with limitation on stack size. For Unix,
-    #define local
-   works also.
- */
-
 #define CHECK_ERR(err, msg) { \
    if (err != Z_OK) { \
        fprintf(stderr, "%s error: %d\n", msg, err); \
@@ -31,32 +22,44 @@ extern void exit  OF((int));
    } \
 }

-char *hello = "hello, hello!";
+const char hello[] = "hello, hello!";
 /* "hello world" would be more standard, but the repeated "hello"
 * stresses the compression code better, sorry...
 */

-void test_compress OF((void));
-void test_gzio     OF((char *out, char *in));
-void test_deflate  OF((Byte compr[]));
-void test_inflate  OF((Byte compr[]));
-void test_flush    OF((Byte compr[]));
-void test_sync     OF((Byte compr[]));
-int  main          OF((int argc, char *argv[]));
+const char dictionary[] = "hello";
+uLong dictId; /* Adler32 value of the dictionary */
+
+void test_compress      OF((Bytef *compr, uLong comprLen,
+		            Bytef *uncompr, uLong uncomprLen));
+void test_gzio          OF((const char *out, const char *in, 
+		            Bytef *uncompr, int uncomprLen));
+void test_deflate       OF((Bytef *compr, uLong comprLen));
+void test_inflate       OF((Bytef *compr, uLong comprLen,
+		            Bytef *uncompr, uLong uncomprLen));
+void test_large_deflate OF((Bytef *compr, uLong comprLen,
+		            Bytef *uncompr, uLong uncomprLen));
+void test_large_inflate OF((Bytef *compr, uLong comprLen,
+		            Bytef *uncompr, uLong uncomprLen));
+void test_flush         OF((Bytef *compr, uLong comprLen));
+void test_sync          OF((Bytef *compr, uLong comprLen,
+		            Bytef *uncompr, uLong uncomprLen));
+void test_dict_deflate  OF((Bytef *compr, uLong comprLen));
+void test_dict_inflate  OF((Bytef *compr, uLong comprLen,
+		            Bytef *uncompr, uLong uncomprLen));
+int  main               OF((int argc, char *argv[]));

 /* ===========================================================================
 * Test compress() and uncompress()
 */
-void test_compress()
+void test_compress(compr, comprLen, uncompr, uncomprLen)
+    Bytef *compr, *uncompr;
+    uLong comprLen, uncomprLen;
 {
-    local Byte compr[BUFLEN];
-    uLong comprLen = sizeof(compr);
-    local Byte uncompr[BUFLEN];
-    uLong uncomprLen = sizeof(uncompr);
    int err;
    uLong len = strlen(hello)+1;

-    err = compress(compr, &comprLen, (Byte*)hello, len);
+    err = compress(compr, &comprLen, (const Bytef*)hello, len);
    CHECK_ERR(err, "compress");

    strcpy((char*)uncompr, "garbage");
@@ -74,12 +77,12 @@ void test_compress()
 /* ===========================================================================
 * Test read/write of .gz files
 */
-void test_gzio(out, in)
-    char *out; /* output file */
-    char *in;  /* input file */
+void test_gzio(out, in, uncompr, uncomprLen)
+    const char *out; /* output file */
+    const char *in;  /* input file */
+    Bytef *uncompr;
+    int  uncomprLen;
 {
-    local Byte uncompr[BUFLEN];
-    int uncomprLen = sizeof(uncompr);
    int err;
    int len = strlen(hello)+1;
    gzFile file;
@@ -90,7 +93,7 @@ void test_gzio(out, in)
        exit(1);
    }

-    if (gzwrite(file, hello, len) != len) {
+    if (gzwrite(file, (const voidp)hello, (unsigned)len) != len) {
        fprintf(stderr, "gzwrite err: %s\n", gzerror(file, &err));
    }
    gzclose(file);
@@ -101,7 +104,7 @@ void test_gzio(out, in)
    }
    strcpy((char*)uncompr, "garbage");

-    uncomprLen = gzread(file, uncompr, uncomprLen);
+    uncomprLen = gzread(file, uncompr, (unsigned)uncomprLen);
    if (uncomprLen != len) {
        fprintf(stderr, "gzread err: %s\n", gzerror(file, &err));
    }
@@ -117,8 +120,9 @@ void test_gzio(out, in)
 /* ===========================================================================
 * Test deflate() with small buffers
 */
-void test_deflate(compr)
-    Byte compr[];
+void test_deflate(compr, comprLen)
+    Bytef *compr;
+    uLong comprLen;
 {
    z_stream c_stream; /* compression stream */
    int err;
@@ -126,14 +130,15 @@ void test_deflate(compr)

    c_stream.zalloc = (alloc_func)0;
    c_stream.zfree = (free_func)0;
+    c_stream.opaque = (voidpf)0;

    err = deflateInit(&c_stream, Z_DEFAULT_COMPRESSION);
    CHECK_ERR(err, "deflateInit");

-    c_stream.next_in  = (Byte*)hello;
+    c_stream.next_in  = (Bytef*)hello;
    c_stream.next_out = compr;

-    while (c_stream.total_in != (uLong)len) {
+    while (c_stream.total_in != (uLong)len && c_stream.total_out < comprLen) {
        c_stream.avail_in = c_stream.avail_out = 1; /* force small buffers */
        err = deflate(&c_stream, Z_NO_FLUSH);
        CHECK_ERR(err, "deflate");
@@ -153,10 +158,10 @@ void test_deflate(compr)
 /* ===========================================================================
 * Test inflate() with small buffers
 */
-void test_inflate(compr)
-    Byte compr[];
+void test_inflate(compr, comprLen, uncompr, uncomprLen)
+    Bytef *compr, *uncompr;
+    uLong comprLen, uncomprLen;
 {
-    local Byte uncompr[BUFLEN];
    int err;
    z_stream d_stream; /* decompression stream */

@@ -164,6 +169,7 @@ void test_inflate(compr)

    d_stream.zalloc = (alloc_func)0;
    d_stream.zfree = (free_func)0;
+    d_stream.opaque = (voidpf)0;

    err = inflateInit(&d_stream);
    CHECK_ERR(err, "inflateInit");
@@ -171,7 +177,7 @@ void test_inflate(compr)
    d_stream.next_in  = compr;
    d_stream.next_out = uncompr;

-    for (;;) {
+    while (d_stream.total_out < uncomprLen && d_stream.total_in < comprLen) {
        d_stream.avail_in = d_stream.avail_out = 1; /* force small buffers */
        err = inflate(&d_stream, Z_NO_FLUSH);
        if (err == Z_STREAM_END) break;
@@ -188,11 +194,105 @@ void test_inflate(compr)
    }
 }

+/* ===========================================================================
+ * Test deflate() with large buffers and dynamic change of compression level
+ */
+void test_large_deflate(compr, comprLen, uncompr, uncomprLen)
+    Bytef *compr, *uncompr;
+    uLong comprLen, uncomprLen;
+{
+    z_stream c_stream; /* compression stream */
+    int err;
+
+    c_stream.zalloc = (alloc_func)0;
+    c_stream.zfree = (free_func)0;
+    c_stream.opaque = (voidpf)0;
+
+    err = deflateInit(&c_stream, Z_BEST_SPEED);
+    CHECK_ERR(err, "deflateInit");
+
+    c_stream.next_out = compr;
+    c_stream.avail_out = (uInt)comprLen;
+
+    /* At this point, uncompr is still mostly zeroes, so it should compress
+     * very well:
+     */
+    c_stream.next_in = uncompr;
+    c_stream.avail_in = (uInt)uncomprLen;
+    err = deflate(&c_stream, Z_NO_FLUSH);
+    CHECK_ERR(err, "deflate");
+    if (c_stream.avail_in != 0) {
+        fprintf(stderr, "deflate not greedy\n");
+    }
+
+    /* Feed in already compressed data and switch to no compression: */
+    deflateParams(&c_stream, Z_NO_COMPRESSION, Z_DEFAULT_STRATEGY);
+    c_stream.next_in = compr;
+    c_stream.avail_in = (uInt)comprLen/2;
+    err = deflate(&c_stream, Z_NO_FLUSH);
+    CHECK_ERR(err, "deflate");
+
+    /* Switch back to compressing mode: */
+    deflateParams(&c_stream, Z_BEST_COMPRESSION, Z_FILTERED);
+    c_stream.next_in = uncompr;
+    c_stream.avail_in = (uInt)uncomprLen;
+    err = deflate(&c_stream, Z_NO_FLUSH);
+    CHECK_ERR(err, "deflate");
+
+    err = deflate(&c_stream, Z_FINISH);
+    if (err != Z_STREAM_END) {
+        fprintf(stderr, "deflate should report Z_STREAM_END\n");
+    }
+    err = deflateEnd(&c_stream);
+    CHECK_ERR(err, "deflateEnd");
+}
+
+/* ===========================================================================
+ * Test inflate() with large buffers
+ */
+void test_large_inflate(compr, comprLen, uncompr, uncomprLen)
+    Bytef *compr, *uncompr;
+    uLong comprLen, uncomprLen;
+{
+    int err;
+    z_stream d_stream; /* decompression stream */
+
+    strcpy((char*)uncompr, "garbage");
+
+    d_stream.zalloc = (alloc_func)0;
+    d_stream.zfree = (free_func)0;
+    d_stream.opaque = (voidpf)0;
+
+    err = inflateInit(&d_stream);
+    CHECK_ERR(err, "inflateInit");
+
+    d_stream.next_in  = compr;
+    d_stream.avail_in = (uInt)comprLen;
+
+    for (;;) {
+        d_stream.next_out = uncompr;            /* discard the output */
+	d_stream.avail_out = (uInt)uncomprLen;
+        err = inflate(&d_stream, Z_NO_FLUSH);
+        if (err == Z_STREAM_END) break;
+        CHECK_ERR(err, "large inflate");
+    }
+
+    err = inflateEnd(&d_stream);
+    CHECK_ERR(err, "inflateEnd");
+
+    if (d_stream.total_out != 2*uncomprLen + comprLen/2) {
+        fprintf(stderr, "bad large inflate: %ld\n", d_stream.total_out);
+    } else {
+        printf("large_inflate(): OK\n");
+    }
+}
+
 /* ===========================================================================
 * Test deflate() with full flush
 */
-void test_flush(compr)
-    Byte compr[];
+void test_flush(compr, comprLen)
+    Bytef *compr;
+    uLong comprLen;
 {
    z_stream c_stream; /* compression stream */
    int err;
@@ -200,14 +300,15 @@ void test_flush(compr)

    c_stream.zalloc = (alloc_func)0;
    c_stream.zfree = (free_func)0;
+    c_stream.opaque = (voidpf)0;

    err = deflateInit(&c_stream, Z_DEFAULT_COMPRESSION);
    CHECK_ERR(err, "deflateInit");

-    c_stream.next_in  = (Byte*)hello;
+    c_stream.next_in  = (Bytef*)hello;
    c_stream.next_out = compr;
    c_stream.avail_in = 3;
-    c_stream.avail_out = BUFLEN;
+    c_stream.avail_out = (uInt)comprLen;
    err = deflate(&c_stream, Z_FULL_FLUSH);
    CHECK_ERR(err, "deflate");

@@ -225,10 +326,10 @@ void test_flush(compr)
 /* ===========================================================================
 * Test inflateSync()
 */
-void test_sync(compr)
-    Byte compr[];
+void test_sync(compr, comprLen, uncompr, uncomprLen)
+    Bytef *compr, *uncompr;
+    uLong comprLen, uncomprLen;
 {
-    local Byte uncompr[BUFLEN];
    int err;
    z_stream d_stream; /* decompression stream */

@@ -236,6 +337,7 @@ void test_sync(compr)

    d_stream.zalloc = (alloc_func)0;
    d_stream.zfree = (free_func)0;
+    d_stream.opaque = (voidpf)0;

    err = inflateInit(&d_stream);
    CHECK_ERR(err, "inflateInit");
@@ -243,13 +345,13 @@ void test_sync(compr)
    d_stream.next_in  = compr;
    d_stream.next_out = uncompr;
    d_stream.avail_in = 2; /* just read the zlib header */
-    d_stream.avail_out = sizeof(uncompr);
+    d_stream.avail_out = (uInt)uncomprLen;

    inflate(&d_stream, Z_NO_FLUSH);
    CHECK_ERR(err, "inflate");

-    d_stream.avail_in = BUFLEN-2; /* let inflate read all compressed data */
-    err = inflateSync(&d_stream); /* skip the damaged part */
+    d_stream.avail_in = (uInt)comprLen-2;   /* read all compressed data */
+    err = inflateSync(&d_stream);           /* but skip the damaged part */
    CHECK_ERR(err, "inflateSync");

    err = inflate(&d_stream, Z_FINISH);
@@ -263,6 +365,91 @@ void test_sync(compr)
    printf("after inflateSync(): hel%s\n", uncompr);
 }

+/* ===========================================================================
+ * Test deflate() with preset dictionary
+ */
+void test_dict_deflate(compr, comprLen)
+    Bytef *compr;
+    uLong comprLen;
+{
+    z_stream c_stream; /* compression stream */
+    int err;
+
+    c_stream.zalloc = (alloc_func)0;
+    c_stream.zfree = (free_func)0;
+    c_stream.opaque = (voidpf)0;
+
+    err = deflateInit(&c_stream, Z_BEST_COMPRESSION);
+    CHECK_ERR(err, "deflateInit");
+
+    err = deflateSetDictionary(&c_stream,
+			       (const Bytef*)dictionary, sizeof(dictionary));
+    CHECK_ERR(err, "deflateSetDictionary");
+
+    dictId = c_stream.adler;
+    c_stream.next_out = compr;
+    c_stream.avail_out = (uInt)comprLen;
+
+    c_stream.next_in = (Bytef*)hello;
+    c_stream.avail_in = (uInt)strlen(hello)+1;
+
+    err = deflate(&c_stream, Z_FINISH);
+    if (err != Z_STREAM_END) {
+        fprintf(stderr, "deflate should report Z_STREAM_END\n");
+    }
+    err = deflateEnd(&c_stream);
+    CHECK_ERR(err, "deflateEnd");
+}
+
+/* ===========================================================================
+ * Test inflate() with a preset dictionary
+ */
+void test_dict_inflate(compr, comprLen, uncompr, uncomprLen)
+    Bytef *compr, *uncompr;
+    uLong comprLen, uncomprLen;
+{
+    int err;
+    z_stream d_stream; /* decompression stream */
+
+    strcpy((char*)uncompr, "garbage");
+
+    d_stream.zalloc = (alloc_func)0;
+    d_stream.zfree = (free_func)0;
+    d_stream.opaque = (voidpf)0;
+
+    err = inflateInit(&d_stream);
+    CHECK_ERR(err, "inflateInit");
+
+    d_stream.next_in  = compr;
+    d_stream.avail_in = (uInt)comprLen;
+
+    d_stream.next_out = uncompr;
+    d_stream.avail_out = (uInt)uncomprLen;
+
+    for (;;) {
+        err = inflate(&d_stream, Z_NO_FLUSH);
+        if (err == Z_STREAM_END) break;
+	if (err == Z_NEED_DICT) {
+	    if (d_stream.adler != dictId) {
+		fprintf(stderr, "unexpected dictionary");
+		exit(1);
+	    }
+	    err = inflateSetDictionary(&d_stream, (const Bytef*)dictionary,
+				       sizeof(dictionary));
+	}
+        CHECK_ERR(err, "inflate with dict");
+    }
+
+    err = inflateEnd(&d_stream);
+    CHECK_ERR(err, "inflateEnd");
+
+    if (strcmp((char*)uncompr, hello)) {
+        fprintf(stderr, "bad inflate with dict\n");
+    } else {
+        printf("inflate with dictionary: %s\n", uncompr);
+    }
+}
+
 /* ===========================================================================
 * Usage:  example [output.gz  [input.gz]]
 */
@@ -271,7 +458,9 @@ int main(argc, argv)
    int argc;
    char *argv[];
 {
-    local Byte compr[BUFLEN];
+    Bytef *compr, *uncompr;
+    uLong comprLen = 32750*sizeof(int); /* don't overflow on MSDOS */
+    uLong uncomprLen = comprLen;

    if (zlib_version[0] != ZLIB_VERSION[0]) {
        fprintf(stderr, "incompatible zlib version\n");
@@ -280,16 +469,31 @@ int main(argc, argv)
    } else if (strcmp(zlib_version, ZLIB_VERSION) != 0) {
        fprintf(stderr, "warning: different zlib version\n");
    }
-    test_compress();
+
+    compr    = (Bytef*)malloc((uInt)comprLen);
+    uncompr  = (Bytef*)calloc((uInt)uncomprLen, 1); /* must be cleared */
+    if (compr == Z_NULL || uncompr == Z_NULL) {
+        printf("out of memory\n");
+	exit(1);
+    }
+
+    test_compress(compr, comprLen, uncompr, uncomprLen);

    test_gzio((argc > 1 ? argv[1] : "foo.gz"),
-              (argc > 2 ? argv[2] : "foo.gz"));
+              (argc > 2 ? argv[2] : "foo.gz"),
+	      uncompr, (int)uncomprLen);

-    test_deflate(compr);
-    test_inflate(compr);
+    test_deflate(compr, comprLen);
+    test_inflate(compr, comprLen, uncompr, uncomprLen);

-    test_flush(compr);
-    test_sync(compr);
+    test_large_deflate(compr, comprLen, uncompr, uncomprLen);
+    test_large_inflate(compr, comprLen, uncompr, uncomprLen);
+
+    test_flush(compr, comprLen);
+    test_sync(compr, comprLen, uncompr, uncomprLen);
+
+    test_dict_deflate(compr, comprLen);
+    test_dict_inflate(compr, comprLen, uncompr, uncomprLen);

    exit(0);
    return 0; /* to avoid warning */
--- a/gzio.c
+++ b/gzio.c
@@ -1,5 +1,5 @@
 /* gzio.c -- IO on .gz files
- * Copyright (C) 1995 Jean-loup Gailly.
+ * Copyright (C) 1995-1996 Jean-loup Gailly.
 * For conditions of distribution and use, see copyright notice in zlib.h
 */

@@ -16,8 +16,7 @@ struct internal_state {int dummy;}; /* for buggy compilers */
 #define ALLOC(size) malloc(size)
 #define TRYFREE(p) {if (p) free(p);}

-#define GZ_MAGIC_1 0x1f
-#define GZ_MAGIC_2 0x8b
+static int gz_magic[2] = {0x1f, 0x8b}; /* gzip magic header */

 /* gzip flag byte */
 #define ASCII_FLAG   0x01 /* bit 0 set: file probably ascii text */
@@ -27,10 +26,6 @@ struct internal_state {int dummy;}; /* for buggy compilers */
 #define COMMENT      0x10 /* bit 4 set: file comment present */
 #define RESERVED     0xE0 /* bits 5..7: reserved */

-#ifndef SEEK_CUR
-#  define SEEK_CUR 1
-#endif
-
 typedef struct gz_stream {
    z_stream stream;
    int      z_err;   /* error code for last stream operation */
@@ -46,44 +41,16 @@ typedef struct gz_stream {
 } gz_stream;


-local int    destroy OF((gz_stream *s));
-local gzFile gz_open OF((char *path, char *mode, int  fd));
-local void   putLong OF((FILE *file, uLong x));
-local uLong  getLong OF((Bytef *buf));
-
- /* ===========================================================================
- * Cleanup then free the given gz_stream. Return a zlib error code.
- */
-local int destroy (s)
-    gz_stream *s;
-{
-    int err = Z_OK;
-
-    if (!s) return Z_STREAM_ERROR;
-
-    TRYFREE(s->inbuf);
-    TRYFREE(s->outbuf);
-    TRYFREE(s->path);
-    TRYFREE(s->msg);
-
-    if (s->stream.state != NULL) {
-       if (s->mode == 'w') {
-           err = deflateEnd(&(s->stream));
-       } else if (s->mode == 'r') {
-           err = inflateEnd(&(s->stream));
-       }
-    }
-    if (s->file != NULL && fclose(s->file)) {
-        err = Z_ERRNO;
-    }
-    if (s->z_err < 0) err = s->z_err;
-    TRYFREE(s);
-    return err;
-}
+local gzFile gz_open      OF((const char *path, const char *mode, int  fd));
+local int    get_byte     OF((gz_stream *s));
+local void   check_header OF((gz_stream *s));
+local int    destroy      OF((gz_stream *s));
+local void   putLong      OF((FILE *file, uLong x));
+local uLong  getLong      OF((gz_stream *s));

 /* ===========================================================================
     Opens a gzip (.gz) file for reading or writing. The mode parameter
-   is as in fopen ("rb" or "wb"). The file is given either by file descritor
+   is as in fopen ("rb" or "wb"). The file is given either by file descriptor
   or path name (if fd == -1).
     gz_open return NULL if the file could not be opened or if there was
   insufficient memory to allocate the (de)compression state; errno
@@ -91,19 +58,25 @@ local int destroy (s)
   zlib error is Z_MEM_ERROR).
 */
 local gzFile gz_open (path, mode, fd)
-    char *path;
-    char *mode;
+    const char *path;
+    const char *mode;
    int  fd;
 {
    int err;
    int level = Z_DEFAULT_COMPRESSION; /* compression level */
-    char *p = mode;
-    gz_stream *s = (gz_stream *)ALLOC(sizeof(gz_stream));
+    char *p = (char*)mode;
+    gz_stream *s;
+    char fmode[80]; /* copy of mode, without the compression level */
+    char *m = fmode;

+    if (!path || !mode) return Z_NULL;
+
+    s = (gz_stream *)ALLOC(sizeof(gz_stream));
    if (!s) return Z_NULL;

    s->stream.zalloc = (alloc_func)0;
    s->stream.zfree = (free_func)0;
+    s->stream.opaque = (voidpf)0;
    s->stream.next_in = s->inbuf = Z_NULL;
    s->stream.next_out = s->outbuf = Z_NULL;
    s->stream.avail_in = s->stream.avail_out = 0;
@@ -123,14 +96,18 @@ local gzFile gz_open (path, mode, fd)
    s->mode = '\0';
    do {
        if (*p == 'r') s->mode = 'r';
-        if (*p == 'w') s->mode = 'w';
-        if (*p >= '1' && *p <= '9') level = *p - '0';
-    } while (*p++);
+        if (*p == 'w' || *p == 'a') s->mode = 'w';
+        if (*p >= '0' && *p <= '9') {
+	    level = *p - '0';
+	} else {
+	    *m++ = *p; /* copy the mode */
+	}
+    } while (*p++ && m != fmode + sizeof(fmode));
    if (s->mode == '\0') return destroy(s), (gzFile)Z_NULL;
    
    if (s->mode == 'w') {
        err = deflateInit2(&(s->stream), level,
-                           DEFLATED, -MAX_WBITS, DEF_MEM_LEVEL, 0);
+                           Z_DEFLATED, -MAX_WBITS, DEF_MEM_LEVEL, 0);
        /* windowBits is passed < 0 to suppress zlib header */

        s->stream.next_out = s->outbuf = (Byte*)ALLOC(Z_BUFSIZE);
@@ -149,7 +126,7 @@ local gzFile gz_open (path, mode, fd)
    s->stream.avail_out = Z_BUFSIZE;

    errno = 0;
-    s->file = fd < 0 ? FOPEN(path, mode) : fdopen(fd, mode);
+    s->file = fd < 0 ? FOPEN(path, fmode) : (FILE*)fdopen(fd, fmode);

    if (s->file == NULL) {
        return destroy(s), (gzFile)Z_NULL;
@@ -157,50 +134,10 @@ local gzFile gz_open (path, mode, fd)
    if (s->mode == 'w') {
        /* Write a very simple .gz header:
         */
-        fprintf(s->file, "%c%c%c%c%c%c%c%c%c%c", GZ_MAGIC_1, GZ_MAGIC_2,
-               DEFLATED, 0 /*flags*/, 0,0,0,0 /*time*/, 0 /*xflags*/, OS_CODE);
+        fprintf(s->file, "%c%c%c%c%c%c%c%c%c%c", gz_magic[0], gz_magic[1],
+             Z_DEFLATED, 0 /*flags*/, 0,0,0,0 /*time*/, 0 /*xflags*/, OS_CODE);
    } else {
-        /* Check and skip the header:
-         */
-        Byte c1 = 0, c2 = 0;
-        Byte method = 0;
-        Byte flags = 0;
-        Byte xflags = 0;
-        Byte time[4];
-        Byte osCode;
-        int c;
-
-        s->stream.avail_in = fread(s->inbuf, 1, 2, s->file);
-        if (s->stream.avail_in != 2 || s->inbuf[0] != GZ_MAGIC_1
-            || s->inbuf[1] != GZ_MAGIC_2) {
-            s->transparent = 1;
-            return (gzFile)s;
-        }
-        s->stream.avail_in = 0;
-        fscanf(s->file,"%c%c%4c%c%c", &method, &flags, time, &xflags, &osCode);
-
-        if (method != DEFLATED || feof(s->file) || (flags & RESERVED) != 0) {
-            s->z_err = Z_DATA_ERROR;
-            return (gzFile)s;
-        }
-        if ((flags & EXTRA_FIELD) != 0) { /* skip the extra field */
-            long len;
-            fscanf(s->file, "%c%c", &c1, &c2);
-            len = c1 + ((long)c2<<8);
-            fseek(s->file, len, SEEK_CUR);
-        }
-        if ((flags & ORIG_NAME) != 0) { /* skip the original file name */
-            while ((c = getc(s->file)) != 0 && c != EOF) ;
-        }
-        if ((flags & COMMENT) != 0) {   /* skip the .gz file comment */
-            while ((c = getc(s->file)) != 0 && c != EOF) ;
-        }
-        if ((flags & HEAD_CRC) != 0) {  /* skip the header crc */
-            fscanf(s->file, "%c%c", &c1, &c2);
-        }
-        if (feof(s->file)) {
-            s->z_err = Z_DATA_ERROR;
-        }
+	check_header(s); /* skip the .gz header */
    }
    return (gzFile)s;
 }
@@ -209,25 +146,138 @@ local gzFile gz_open (path, mode, fd)
     Opens a gzip (.gz) file for reading or writing.
 */
 gzFile gzopen (path, mode)
-    char *path;
-    char *mode;
+    const char *path;
+    const char *mode;
 {
    return gz_open (path, mode, -1);
 }

 /* ===========================================================================
-     Associate a gzFile with the file descriptor fd.
+     Associate a gzFile with the file descriptor fd. fd is not dup'ed here
+   to mimic the behavio(u)r of fdopen.
 */
 gzFile gzdopen (fd, mode)
    int fd;
-    char *mode;
+    const char *mode;
 {
    char name[20];
+
+    if (fd < 0) return (gzFile)Z_NULL;
    sprintf(name, "<fd:%d>", fd); /* for debugging */

    return gz_open (name, mode, fd);
 }

+/* ===========================================================================
+     Read a byte from a gz_stream; update next_in and avail_in. Return EOF
+   for end of file.
+   IN assertion: the stream s has been sucessfully opened for reading.
+*/
+local int get_byte(s)
+    gz_stream *s;
+{
+    if (s->z_eof) return EOF;
+    if (s->stream.avail_in == 0) {
+	errno = 0;
+	s->stream.avail_in = fread(s->inbuf, 1, Z_BUFSIZE, s->file);
+	if (s->stream.avail_in == 0) {
+	    s->z_eof = 1;
+	    if (ferror(s->file)) s->z_err = Z_ERRNO;
+	    return EOF;
+	}
+	s->stream.next_in = s->inbuf;
+    }
+    s->stream.avail_in--;
+    return *(s->stream.next_in)++;
+}
+
+/* ===========================================================================
+      Check the gzip header of a gz_stream opened for reading. Set the stream
+    mode to transparent if the gzip magic header is not present; set s->err
+    to Z_DATA_ERROR if the magic header is present but the rest of the header
+    is incorrect.
+    IN assertion: the stream s has already been created sucessfully;
+       s->stream.avail_in is zero for the first time, but may be non-zero
+       for concatenated .gz files.
+*/
+local void check_header(s)
+    gz_stream *s;
+{
+    int method = 0;
+    int flags = 0;
+    uInt len;
+    int c;
+
+    /* Check the gzip magic header */
+    for (len = 0; len < 2; len++) {
+	c = get_byte(s);
+	if (c != gz_magic[len]) {
+	    s->transparent = 1;
+	    if (c != EOF) s->stream.avail_in++, s->stream.next_in--;
+	    s->z_err = s->stream.avail_in != 0 ? Z_OK : Z_STREAM_END;
+	    return;
+	}
+    }
+    method = get_byte(s);
+    flags = get_byte(s);
+    if (method != Z_DEFLATED || (flags & RESERVED) != 0) {
+	s->z_err = Z_DATA_ERROR;
+	return;
+    }
+
+    /* Discard time, xflags and OS code: */
+    for (len = 0; len < 6; len++) (void)get_byte(s);
+
+    if ((flags & EXTRA_FIELD) != 0) { /* skip the extra field */
+	len  =  (uInt)get_byte(s);
+	len += ((uInt)get_byte(s))<<8;
+	/* len is garbage if EOF but the loop below will quit anyway */
+	while (len-- != 0 && get_byte(s) != EOF) ;
+    }
+    if ((flags & ORIG_NAME) != 0) { /* skip the original file name */
+	while ((c = get_byte(s)) != 0 && c != EOF) ;
+    }
+    if ((flags & COMMENT) != 0) {   /* skip the .gz file comment */
+	while ((c = get_byte(s)) != 0 && c != EOF) ;
+    }
+    if ((flags & HEAD_CRC) != 0) {  /* skip the header crc */
+	for (len = 0; len < 2; len++) (void)get_byte(s);
+    }
+    s->z_err = s->z_eof ? Z_DATA_ERROR : Z_OK;
+}
+
+ /* ===========================================================================
+ * Cleanup then free the given gz_stream. Return a zlib error code.
+   Try freeing in the reverse order of allocations.
+ */
+local int destroy (s)
+    gz_stream *s;
+{
+    int err = Z_OK;
+
+    if (!s) return Z_STREAM_ERROR;
+
+    TRYFREE(s->msg);
+
+    if (s->stream.state != NULL) {
+       if (s->mode == 'w') {
+           err = deflateEnd(&(s->stream));
+       } else if (s->mode == 'r') {
+           err = inflateEnd(&(s->stream));
+       }
+    }
+    if (s->file != NULL && fclose(s->file)) {
+        err = Z_ERRNO;
+    }
+    if (s->z_err < 0) err = s->z_err;
+
+    TRYFREE(s->inbuf);
+    TRYFREE(s->outbuf);
+    TRYFREE(s->path);
+    TRYFREE(s);
+    return err;
+}
+
 /* ===========================================================================
     Reads the given number of uncompressed bytes from the compressed file.
   gzread returns the number of bytes actually read (0 for end of file).
@@ -238,52 +288,71 @@ int gzread (file, buf, len)
    unsigned len;
 {
    gz_stream *s = (gz_stream*)file;
+    Byte *start = buf; /* starting point for crc computation */

    if (s == NULL || s->mode != 'r') return Z_STREAM_ERROR;

-    if (s->transparent) {
-        int n = 0;
-        Byte *b = (Byte*)buf;
-        /* Copy the first two (non-magic) bytes if not done already */
-        while (s->stream.avail_in > 0 && len > 0) {
-            *b++ = *s->stream.next_in++;
-            s->stream.avail_in--;
-            len--; n++;
-        }
-        if (len == 0) return n;
-        return n + fread(b, 1, len, s->file);
-    }
-    if (s->z_err == Z_DATA_ERROR) return -1; /* bad .gz file */
-    if (s->z_err == Z_STREAM_END) return 0;  /* don't read crc as data */
+    if (s->z_err == Z_DATA_ERROR || s->z_err == Z_ERRNO) return -1;
+    if (s->z_err == Z_STREAM_END) return 0;  /* EOF */

    s->stream.next_out = buf;
    s->stream.avail_out = len;

    while (s->stream.avail_out != 0) {

+	if (s->transparent) {
+	    /* Copy first the lookahead bytes: */
+	    uInt n = s->stream.avail_in;
+	    if (n > s->stream.avail_out) n = s->stream.avail_out;
+	    if (n > 0) {
+		zmemcpy(s->stream.next_out, s->stream.next_in, n);
+		s->stream.next_out  += n;
+		s->stream.next_in   += n;
+		s->stream.avail_out -= n;
+		s->stream.avail_in  -= n;
+	    }
+	    if (s->stream.avail_out > 0) {
+		s->stream.avail_out -= fread(s->stream.next_out,
+					     1, s->stream.avail_out, s->file);
+	    }
+	    return (int)(len - s->stream.avail_out);
+	}
        if (s->stream.avail_in == 0 && !s->z_eof) {

            errno = 0;
-            s->stream.avail_in =
-                fread(s->inbuf, 1, Z_BUFSIZE, s->file);
+            s->stream.avail_in = fread(s->inbuf, 1, Z_BUFSIZE, s->file);
            if (s->stream.avail_in == 0) {
                s->z_eof = 1;
-            } else if (s->stream.avail_in == (uInt)EOF) {
-                s->stream.avail_in = 0;
-                s->z_eof = 1;
-                s->z_err = Z_ERRNO;
-                break;
+		if (ferror(s->file)) {
+		    s->z_err = Z_ERRNO;
+		    break;
+		}
            }
            s->stream.next_in = s->inbuf;
        }
        s->z_err = inflate(&(s->stream), Z_NO_FLUSH);

-        if (s->z_err == Z_STREAM_END ||
-            s->z_err != Z_OK  || s->z_eof) break;
+	if (s->z_err == Z_STREAM_END) {
+	    /* Check CRC and original size */
+	    s->crc = crc32(s->crc, start, (uInt)(s->stream.next_out - start));
+	    start = s->stream.next_out;
+
+	    if (getLong(s) != s->crc || getLong(s) != s->stream.total_out) {
+		s->z_err = Z_DATA_ERROR;
+	    } else {
+		/* Check for concatenated .gz files: */
+		check_header(s);
+		if (s->z_err == Z_OK) {
+		    inflateReset(&(s->stream));
+		    s->crc = crc32(0L, Z_NULL, 0);
+		}
+	    }
+	}
+	if (s->z_err != Z_OK || s->z_eof) break;
    }
-    len -= s->stream.avail_out;
-    s->crc = crc32(s->crc, buf, len);
-    return (int)len;
+    s->crc = crc32(s->crc, start, (uInt)(s->stream.next_out - start));
+
+    return (int)(len - s->stream.avail_out);
 }

 /* ===========================================================================
@@ -292,7 +361,7 @@ int gzread (file, buf, len)
 */
 int gzwrite (file, buf, len)
    gzFile file;
-    voidp buf;
+    const voidp buf;
    unsigned len;
 {
    gz_stream *s = (gz_stream*)file;
@@ -343,7 +412,7 @@ int gzflush (file, flush)
        len = Z_BUFSIZE - s->stream.avail_out;

        if (len != 0) {
-            if (fwrite(s->outbuf, 1, len, s->file) != len) {
+            if ((uInt)fwrite(s->outbuf, 1, len, s->file) != len) {
                s->z_err = Z_ERRNO;
                return Z_ERRNO;
            }
@@ -379,18 +448,19 @@ local void putLong (file, x)
 }

 /* ===========================================================================
-   Reads a long in LSB order from the given buffer
+   Reads a long in LSB order from the given gz_stream. Sets 
 */
-local uLong getLong (buf)
-    Bytef *buf;
+local uLong getLong (s)
+    gz_stream *s;
 {
-    uLong x = 0;
-    Bytef *p = buf+4;
+    uLong x = (uLong)get_byte(s);
+    int c;

-    do {
-        x <<= 8;
-        x |= *--p; 
-    } while (p != buf);
+    x += ((uLong)get_byte(s))<<8;
+    x += ((uLong)get_byte(s))<<16;
+    c = get_byte(s);
+    if (c == EOF) s->z_err = Z_DATA_ERROR;
+    x += ((uLong)c)<<24;
    return x;
 }

@@ -401,7 +471,6 @@ local uLong getLong (buf)
 int gzclose (file)
    gzFile file;
 {
-    uInt n;
    int err;
    gz_stream *s = (gz_stream*)file;

@@ -414,25 +483,6 @@ int gzclose (file)
        putLong (s->file, s->crc);
        putLong (s->file, s->stream.total_in);

-    } else if (s->mode == 'r' && s->z_err == Z_STREAM_END) {
-
-        /* slide CRC and original size if they are at the end of inbuf */
-        if ((n = s->stream.avail_in) < 8  && !s->z_eof) {
-            Byte *p = s->inbuf;
-	    Bytef *q = s->stream.next_in;
-            while (n--) { *p++ = *q++; };
-
-            n = s->stream.avail_in;
-            n += fread(p, 1, 8, s->file);
-            s->stream.next_in = s->inbuf;
-        }
-        /* check CRC and original size */
-        if (n < 8 ||
-            getLong(s->stream.next_in) != s->crc ||
-            getLong(s->stream.next_in + 4) != s->stream.total_out) {
-
-            s->z_err = Z_DATA_ERROR;
-        }
    }
    return destroy(file);
 }
@@ -453,14 +503,14 @@ char*  gzerror (file, errnum)

    if (s == NULL) {
        *errnum = Z_STREAM_ERROR;
-        return z_errmsg[1-Z_STREAM_ERROR];
+        return ERR_MSG(Z_STREAM_ERROR);
    }
    *errnum = s->z_err;
-    if (*errnum == Z_OK) return "";
+    if (*errnum == Z_OK) return (char*)"";

-    m =  *errnum == Z_ERRNO ? zstrerror(errno) : s->stream.msg;
+    m =  (char*)(*errnum == Z_ERRNO ? zstrerror(errno) : s->stream.msg);

-    if (m == NULL || *m == '\0') m = z_errmsg[1-s->z_err];
+    if (m == NULL || *m == '\0') m = (char*)z_errmsg[1-s->z_err];

    TRYFREE(s->msg);
    s->msg = (char*)ALLOC(strlen(s->path) + strlen(m) + 3);
--- a/infblock.c
+++ b/infblock.c
@@ -1,5 +1,5 @@
 /* infblock.c -- interpret and process block types to last block
- * Copyright (C) 1995 Mark Adler
+ * Copyright (C) 1995-1996 Mark Adler
 * For conditions of distribution and use, see copyright notice in zlib.h 
 */

@@ -81,7 +81,7 @@ uLongf *c;
  s->bitb = 0;
  s->read = s->write = s->window;
  if (s->checkfn != Z_NULL)
-    s->check = (*s->checkfn)(0L, Z_NULL, 0);
+    z->adler = s->check = (*s->checkfn)(0L, Z_NULL, 0);
  Trace((stderr, "inflate:   blocks reset\n"));
 }

@@ -172,17 +172,17 @@ int r;
        case 3:                         /* illegal */
          DUMPBITS(3)
          s->mode = BAD;
-          z->msg = "invalid block type";
+          z->msg = (char*)"invalid block type";
          r = Z_DATA_ERROR;
          LEAVE
      }
      break;
    case LENS:
      NEEDBITS(32)
-      if (((~b) >> 16) != (b & 0xffff))
+      if ((((~b) >> 16) & 0xffff) != (b & 0xffff))
      {
        s->mode = BAD;
-        z->msg = "invalid stored block lengths";
+        z->msg = (char*)"invalid stored block lengths";
        r = Z_DATA_ERROR;
        LEAVE
      }
@@ -215,7 +215,7 @@ int r;
      if ((t & 0x1f) > 29 || ((t >> 5) & 0x1f) > 29)
      {
        s->mode = BAD;
-        z->msg = "too many length or distance symbols";
+        z->msg = (char*)"too many length or distance symbols";
        r = Z_DATA_ERROR;
        LEAVE
      }
@@ -285,7 +285,7 @@ int r;
              (c == 16 && i < 1))
          {
            s->mode = BAD;
-            z->msg = "invalid bit length repeat";
+            z->msg = (char*)"invalid bit length repeat";
            r = Z_DATA_ERROR;
            LEAVE
          }
@@ -383,3 +383,14 @@ uLongf *c;
  Trace((stderr, "inflate:   blocks freed\n"));
  return Z_OK;
 }
+
+
+void inflate_set_dictionary(s, z, d, n)
+inflate_blocks_statef *s;
+z_stream *z;
+const Bytef *d;
+uInt  n;
+{
+  zmemcpy((charf *)s->window, d, n);
+  s->read = s->write = s->window + n;
+}
--- a/infblock.h
+++ b/infblock.h
@@ -1,5 +1,5 @@
 /* infblock.h -- header to use infblock.c
- * Copyright (C) 1995 Mark Adler
+ * Copyright (C) 1995-1996 Mark Adler
 * For conditions of distribution and use, see copyright notice in zlib.h 
 */

@@ -30,3 +30,9 @@ extern int inflate_blocks_free OF((
    inflate_blocks_statef *,
    z_stream *,
    uLongf *));                  /* check value on output */
+
+extern void inflate_set_dictionary OF((
+    inflate_blocks_statef *s,
+    z_stream *z,
+    const Bytef *d,  /* dictionary */
+    uInt  n));       /* dictionary length */
--- a/infcodes.c
+++ b/infcodes.c
@@ -1,5 +1,5 @@
 /* infcodes.c -- process literals and length/distance pairs
- * Copyright (C) 1995 Mark Adler
+ * Copyright (C) 1995-1996 Mark Adler
 * For conditions of distribution and use, see copyright notice in zlib.h 
 */

@@ -58,7 +58,8 @@ struct inflate_codes_state {

 inflate_codes_statef *inflate_codes_new(bl, bd, tl, td, z)
 uInt bl, bd;
-inflate_huft *tl, *td;
+inflate_huft *tl;
+inflate_huft *td; /* need separate declaration for Borland C++ */
 z_stream *z;
 {
  inflate_codes_statef *c;
@@ -152,7 +153,7 @@ int r;
        break;
      }
      c->mode = BADCODE;        /* invalid code */
-      z->msg = "invalid literal/length code";
+      z->msg = (char*)"invalid literal/length code";
      r = Z_DATA_ERROR;
      LEAVE
    case LENEXT:        /* i: getting length extra (have base) */
@@ -184,7 +185,7 @@ int r;
        break;
      }
      c->mode = BADCODE;        /* invalid code */
-      z->msg = "invalid distance code";
+      z->msg = (char*)"invalid distance code";
      r = Z_DATA_ERROR;
      LEAVE
    case DISTEXT:       /* i: getting distance extra */
@@ -202,7 +203,7 @@ int r;
 #else
      f = q - c->sub.copy.dist;
      if ((uInt)(q - s->window) < c->sub.copy.dist)
-        f = s->end - (c->sub.copy.dist - (q - s->window));
+        f = s->end - (c->sub.copy.dist - (uInt)(q - s->window));
 #endif
      while (c->len)
      {
--- a/infcodes.h
+++ b/infcodes.h
@@ -1,5 +1,5 @@
 /* infcodes.h -- header to use infcodes.c
- * Copyright (C) 1995 Mark Adler
+ * Copyright (C) 1995-1996 Mark Adler
 * For conditions of distribution and use, see copyright notice in zlib.h 
 */

--- a/inffast.c
+++ b/inffast.c
@@ -1,5 +1,5 @@
 /* inffast.c -- process literals and length/distance pairs fast
- * Copyright (C) 1995 Mark Adler
+ * Copyright (C) 1995-1996 Mark Adler
 * For conditions of distribution and use, see copyright notice in zlib.h 
 */

@@ -29,7 +29,8 @@ struct inflate_codes_state {int dummy;}; /* for buggy compilers */

 int inflate_fast(bl, bd, tl, td, s, z)
 uInt bl, bd;
-inflate_huft *tl, *td;
+inflate_huft *tl;
+inflate_huft *td; /* need separate declaration for Borland C++ */
 inflate_blocks_statef *s;
 z_stream *z;
 {
@@ -102,7 +103,7 @@ z_stream *z;
            }
            else                        /* else offset after destination */
            {
-              e = d - (q - s->window);  /* bytes from offset to end */
+              e = d - (uInt)(q - s->window); /* bytes from offset to end */
              r = s->end - e;           /* pointer to offset */
              if (c > e)                /* if source crosses, */
              {
@@ -122,7 +123,7 @@ z_stream *z;
            e = (t = t->next + ((uInt)b & inflate_mask[e]))->exop;
          else
          {
-            z->msg = "invalid distance code";
+            z->msg = (char*)"invalid distance code";
            UNGRAB
            UPDATE
            return Z_DATA_ERROR;
@@ -152,7 +153,7 @@ z_stream *z;
      }
      else
      {
-        z->msg = "invalid literal/length code";
+        z->msg = (char*)"invalid literal/length code";
        UNGRAB
        UPDATE
        return Z_DATA_ERROR;
--- a/inffast.h
+++ b/inffast.h
@@ -1,5 +1,5 @@
 /* inffast.h -- header to use inffast.c
- * Copyright (C) 1995 Mark Adler
+ * Copyright (C) 1995-1996 Mark Adler
 * For conditions of distribution and use, see copyright notice in zlib.h 
 */

--- a/inflate.c
+++ b/inflate.c
@@ -1,5 +1,5 @@
 /* inflate.c -- zlib interface to inflate modules
- * Copyright (C) 1995 Mark Adler
+ * Copyright (C) 1995-1996 Mark Adler
 * For conditions of distribution and use, see copyright notice in zlib.h 
 */

@@ -15,6 +15,11 @@ struct internal_state {
  enum {
      METHOD,   /* waiting for method byte */
      FLAG,     /* waiting for flag byte */
+      DICT4,    /* four dictionary check bytes to go */
+      DICT3,    /* three dictionary check bytes to go */
+      DICT2,    /* two dictionary check bytes to go */
+      DICT1,    /* one dictionary check byte to go */
+      DICT0,    /* waiting for inflateSetDictionary */
      BLOCKS,   /* decompressing blocks */
      CHECK4,   /* four check bytes to go */
      CHECK3,   /* three check bytes to go */
@@ -75,14 +80,25 @@ z_stream *z;
 }


-int inflateInit2(z, w)
+int inflateInit2_(z, w, version, stream_size)
 z_stream *z;
 int w;
+const char *version;
+int stream_size;
 {
+  if (version == Z_NULL || version[0] != ZLIB_VERSION[0] ||
+      stream_size != sizeof(z_stream))
+      return Z_VERSION_ERROR;
+
  /* initialize state */
  if (z == Z_NULL)
    return Z_STREAM_ERROR;
-  if (z->zalloc == Z_NULL) z->zalloc = zcalloc;
+  z->msg = Z_NULL;
+  if (z->zalloc == Z_NULL)
+  {
+    z->zalloc = zcalloc;
+    z->opaque = (voidpf)0;
+  }
  if (z->zfree == Z_NULL) z->zfree = zcfree;
  if ((z->state = (struct internal_state FAR *)
       ZALLOC(z,1,sizeof(struct internal_state))) == Z_NULL)
@@ -107,7 +123,7 @@ int w;

  /* create inflate_blocks state */
  if ((z->state->blocks =
-       inflate_blocks_new(z, z->state->nowrap ? Z_NULL : adler32, 1 << w))
+      inflate_blocks_new(z, z->state->nowrap ? Z_NULL : adler32, (uInt)1 << w))
      == Z_NULL)
  {
    inflateEnd(z);
@@ -121,10 +137,12 @@ int w;
 }


-int inflateInit(z)
+int inflateInit_(z, version, stream_size)
 z_stream *z;
+const char *version;
+int stream_size;
 {
-  return inflateInit2(z, DEF_WBITS);
+  return inflateInit2_(z, DEF_WBITS, version, stream_size);
 }


@@ -138,46 +156,68 @@ int f;
  int r = f;    /* to avoid warning about unused f */
  uInt b;

-  if (z == Z_NULL || z->next_in == Z_NULL)
+  if (z == Z_NULL || z->state == Z_NULL || z->next_in == Z_NULL)
    return Z_STREAM_ERROR;
  r = Z_BUF_ERROR;
  while (1) switch (z->state->mode)
  {
    case METHOD:
      NEEDBYTE
-      if (((z->state->sub.method = NEXTBYTE) & 0xf) != DEFLATED)
+      if (((z->state->sub.method = NEXTBYTE) & 0xf) != Z_DEFLATED)
      {
        z->state->mode = BAD;
-        z->msg = "unknown compression method";
+        z->msg = (char*)"unknown compression method";
        z->state->sub.marker = 5;       /* can't try inflateSync */
        break;
      }
      if ((z->state->sub.method >> 4) + 8 > z->state->wbits)
      {
        z->state->mode = BAD;
-        z->msg = "invalid window size";
+        z->msg = (char*)"invalid window size";
        z->state->sub.marker = 5;       /* can't try inflateSync */
        break;
      }
      z->state->mode = FLAG;
    case FLAG:
      NEEDBYTE
-      if ((b = NEXTBYTE) & 0x20)
-      {
-        z->state->mode = BAD;
-        z->msg = "invalid reserved bit";
-        z->state->sub.marker = 5;       /* can't try inflateSync */
-        break;
-      }
+      b = NEXTBYTE;
      if (((z->state->sub.method << 8) + b) % 31)
      {
        z->state->mode = BAD;
-        z->msg = "incorrect header check";
+        z->msg = (char*)"incorrect header check";
        z->state->sub.marker = 5;       /* can't try inflateSync */
        break;
      }
      Trace((stderr, "inflate: zlib header ok\n"));
-      z->state->mode = BLOCKS;
+      if (!(b & PRESET_DICT))
+      {
+        z->state->mode = BLOCKS;
+	break;
+      }
+      z->state->mode = DICT4;
+    case DICT4:
+      NEEDBYTE
+      z->state->sub.check.need = (uLong)NEXTBYTE << 24;
+      z->state->mode = DICT3;
+    case DICT3:
+      NEEDBYTE
+      z->state->sub.check.need += (uLong)NEXTBYTE << 16;
+      z->state->mode = DICT2;
+    case DICT2:
+      NEEDBYTE
+      z->state->sub.check.need += (uLong)NEXTBYTE << 8;
+      z->state->mode = DICT1;
+    case DICT1:
+      NEEDBYTE
+      z->state->sub.check.need += (uLong)NEXTBYTE;
+      z->adler = z->state->sub.check.need;
+      z->state->mode = DICT0;
+      return Z_NEED_DICT;
+    case DICT0:
+      z->state->mode = BAD;
+      z->msg = (char*)"need dictionary";
+      z->state->sub.marker = 0;       /* can try inflateSync */
+      return Z_STREAM_ERROR;
    case BLOCKS:
      r = inflate_blocks(z->state->blocks, z, r);
      if (r == Z_DATA_ERROR)
@@ -215,7 +255,7 @@ int f;
      if (z->state->sub.check.was != z->state->sub.check.need)
      {
        z->state->mode = BAD;
-        z->msg = "incorrect data check";
+        z->msg = (char*)"incorrect data check";
        z->state->sub.marker = 5;       /* can't try inflateSync */
        break;
      }
@@ -231,6 +271,29 @@ int f;
 }


+int inflateSetDictionary(z, dictionary, dictLength)
+z_stream *z;
+const Bytef *dictionary;
+uInt  dictLength;
+{
+  uInt length = dictLength;
+
+  if (z == Z_NULL || z->state == Z_NULL || z->state->mode != DICT0)
+    return Z_STREAM_ERROR;
+  if (adler32(1L, dictionary, dictLength) != z->adler) return Z_DATA_ERROR;
+  z->adler = 1L;
+
+  if (length >= (1<<z->state->wbits))
+  {
+    length = (1<<z->state->wbits)-1;
+    dictionary += dictLength - length;
+  }
+  inflate_set_dictionary(z->state->blocks, z, dictionary, length);
+  z->state->mode = BLOCKS;
+  return Z_OK;
+}
+
+
 int inflateSync(z)
 z_stream *z;
 {
--- a/inftrees.c
+++ b/inftrees.c
@@ -1,11 +1,18 @@
 /* inftrees.c -- generate Huffman trees for efficient decoding
- * Copyright (C) 1995 Mark Adler
+ * Copyright (C) 1995-1996 Mark Adler
 * For conditions of distribution and use, see copyright notice in zlib.h 
 */

 #include "zutil.h"
 #include "inftrees.h"

+char inflate_copyright[] = " inflate 1.0 Copyright 1995-1996 Mark Adler ";
+/*
+  If you use the zlib library in a product, an acknowledgment is welcome
+  in the documentation of your product. If for some reason you cannot
+  include such an acknowledgment, I would appreciate that you keep this
+  copyright string in the executable of your product.
+ */
 struct internal_state  {int dummy;}; /* for buggy compilers */

 /* simplify the use of the inflate_huft type with some defines */
@@ -30,23 +37,19 @@ local voidpf falloc OF((
    uInt,               /* number of items */
    uInt));             /* size of item */

-local void ffree OF((
-    voidpf q,            /* opaque pointer (not used) */
-    voidpf p));          /* what to free (not used) */
-
 /* Tables for deflate from PKZIP's appnote.txt. */
-local uInt cplens[] = { /* Copy lengths for literal codes 257..285 */
+local uInt cplens[31] = { /* Copy lengths for literal codes 257..285 */
        3, 4, 5, 6, 7, 8, 9, 10, 11, 13, 15, 17, 19, 23, 27, 31,
        35, 43, 51, 59, 67, 83, 99, 115, 131, 163, 195, 227, 258, 0, 0};
        /* actually lengths - 2; also see note #13 above about 258 */
-local uInt cplext[] = { /* Extra bits for literal codes 257..285 */
+local uInt cplext[31] = { /* Extra bits for literal codes 257..285 */
        0, 0, 0, 0, 0, 0, 0, 0, 1, 1, 1, 1, 2, 2, 2, 2,
        3, 3, 3, 3, 4, 4, 4, 4, 5, 5, 5, 5, 0, 192, 192}; /* 192==invalid */
-local uInt cpdist[] = { /* Copy offsets for distance codes 0..29 */
+local uInt cpdist[30] = { /* Copy offsets for distance codes 0..29 */
        1, 2, 3, 4, 5, 7, 9, 13, 17, 25, 33, 49, 65, 97, 129, 193,
        257, 385, 513, 769, 1025, 1537, 2049, 3073, 4097, 6145,
        8193, 12289, 16385, 24577};
-local uInt cpdext[] = { /* Extra bits for distance codes */
+local uInt cpdext[30] = { /* Extra bits for distance codes */
        0, 0, 0, 0, 1, 1, 2, 2, 3, 3, 4, 4, 5, 5, 6, 6,
        7, 7, 8, 8, 9, 9, 10, 10, 11, 11,
        12, 12, 13, 13};
@@ -304,11 +307,11 @@ z_stream *z;            /* for zfree function */

  r = huft_build(c, 19, 19, (uIntf*)Z_NULL, (uIntf*)Z_NULL, tb, bb, z);
  if (r == Z_DATA_ERROR)
-    z->msg = "oversubscribed dynamic bit lengths tree";
+    z->msg = (char*)"oversubscribed dynamic bit lengths tree";
  else if (r == Z_BUF_ERROR)
  {
    inflate_trees_free(*tb, z);
-    z->msg = "incomplete dynamic bit lengths tree";
+    z->msg = (char*)"incomplete dynamic bit lengths tree";
    r = Z_DATA_ERROR;
  }
  return r;
@@ -331,11 +334,11 @@ z_stream *z;            /* for zfree function */
  if ((r = huft_build(c, nl, 257, cplens, cplext, tl, bl, z)) != Z_OK)
  {
    if (r == Z_DATA_ERROR)
-      z->msg = "oversubscribed literal/length tree";
+      z->msg = (char*)"oversubscribed literal/length tree";
    else if (r == Z_BUF_ERROR)
    {
      inflate_trees_free(*tl, z);
-      z->msg = "incomplete literal/length tree";
+      z->msg = (char*)"incomplete literal/length tree";
      r = Z_DATA_ERROR;
    }
    return r;
@@ -345,14 +348,14 @@ z_stream *z;            /* for zfree function */
  if ((r = huft_build(c + nl, nd, 0, cpdist, cpdext, td, bd, z)) != Z_OK)
  {
    if (r == Z_DATA_ERROR)
-      z->msg = "oversubscribed literal/length tree";
+      z->msg = (char*)"oversubscribed literal/length tree";
    else if (r == Z_BUF_ERROR) {
 #ifdef PKZIP_BUG_WORKAROUND
      r = Z_OK;
    }
 #else
      inflate_trees_free(*td, z);
-      z->msg = "incomplete literal/length tree";
+      z->msg = (char*)"incomplete literal/length tree";
      r = Z_DATA_ERROR;
    }
    inflate_trees_free(*tl, z);
@@ -366,10 +369,8 @@ z_stream *z;            /* for zfree function */


 /* build fixed tables only once--keep them here */
-local int fixed_lock = 0;
 local int fixed_built = 0;
 #define FIXEDH 530      /* number of hufts used by fixed tables */
-local uInt fixed_left = FIXEDH;
 local inflate_huft fixed_mem[FIXEDH];
 local uInt fixed_bl;
 local uInt fixed_bd;
@@ -378,24 +379,14 @@ local inflate_huft *fixed_td;


 local voidpf falloc(q, n, s)
-voidpf q;        /* opaque pointer (not used) */
+voidpf q;       /* opaque pointer */
 uInt n;         /* number of items */
 uInt s;         /* size of item */
 {
-  Assert(s == sizeof(inflate_huft) && n <= fixed_left,
+  Assert(s == sizeof(inflate_huft) && n <= *(intf *)q,
         "inflate_trees falloc overflow");
-  if (q) s++; /* to make some compilers happy */
-  fixed_left -= n;
-  return (voidpf)(fixed_mem + fixed_left);
-}
-
-
-local void ffree(q, p)
-voidpf q;
-voidpf p;
-{
-  Assert(0, "inflate_trees ffree called!");
-  if (q) q = p; /* to make some compilers happy */
+  *(intf *)q -= n+s-s; /* s-s to avoid warning */
+  return (voidpf)(fixed_mem + *(intf *)q);
 }


@@ -405,19 +396,18 @@ uIntf *bd;               /* distance desired/actual bit depth */
 inflate_huft * FAR *tl;  /* literal/length tree result */
 inflate_huft * FAR *td;  /* distance tree result */
 {
-  /* build fixed tables if not built already--lock out other instances */
-  while (++fixed_lock > 1)
-    fixed_lock--;
+  /* build fixed tables if not already (multiple overlapped executions ok) */
  if (!fixed_built)
  {
    int k;              /* temporary variable */
    unsigned c[288];    /* length list for huft_build */
    z_stream z;         /* for falloc function */
+    int f = FIXEDH;     /* number of hufts left in fixed_mem */

    /* set up fake z_stream for memory routines */
    z.zalloc = falloc;
-    z.zfree = ffree;
-    z.opaque = Z_NULL;
+    z.zfree = Z_NULL;
+    z.opaque = (voidpf)&f;

    /* literal table */
    for (k = 0; k < 144; k++)
@@ -438,9 +428,9 @@ inflate_huft * FAR *td;  /* distance tree result */
    huft_build(c, 30, 0, cpdist, cpdext, &fixed_td, &fixed_bd, &z);

    /* done */
+    Assert(f == 0, "invalid build of fixed tables");
    fixed_built = 1;
  }
-  fixed_lock--;
  *bl = fixed_bl;
  *bd = fixed_bd;
  *tl = fixed_tl;
@@ -456,10 +446,19 @@ z_stream *z;            /* for zfree function */
   list of the tables it made, with the links in a dummy first entry of
   each table. */
 {
-  register inflate_huft *p, *q;
+  register inflate_huft *p, *q, *r;

+  /* Reverse linked list */
+  p = Z_NULL;
+  q = t;
+  while (q != Z_NULL)
+  {
+    r = (q - 1)->next;
+    (q - 1)->next = p;
+    p = q;
+    q = r;
+  }
  /* Go through linked list, freeing from the malloced (t[-1]) address. */
-  p = t;
  while (p != Z_NULL)
  {
    q = (--p)->next;
--- a/inftrees.h
+++ b/inftrees.h
@@ -1,5 +1,5 @@
 /* inftrees.h -- header to use inftrees.c
- * Copyright (C) 1995 Mark Adler
+ * Copyright (C) 1995-1996 Mark Adler
 * For conditions of distribution and use, see copyright notice in zlib.h 
 */

--- a/infutil.c
+++ b/infutil.c
@@ -1,5 +1,5 @@
 /* inflate_util.c -- data and routines common to blocks and codes
- * Copyright (C) 1995 Mark Adler
+ * Copyright (C) 1995-1996 Mark Adler
 * For conditions of distribution and use, see copyright notice in zlib.h 
 */

@@ -12,7 +12,7 @@
 struct inflate_codes_state {int dummy;}; /* for buggy compilers */

 /* And'ing with mask[n] masks the lower n bits */
-uInt inflate_mask[] = {
+uInt inflate_mask[17] = {
    0x0000,
    0x0001, 0x0003, 0x0007, 0x000f, 0x001f, 0x003f, 0x007f, 0x00ff,
    0x01ff, 0x03ff, 0x07ff, 0x0fff, 0x1fff, 0x3fff, 0x7fff, 0xffff
@@ -43,7 +43,7 @@ int r;

  /* update check information */
  if (s->checkfn != Z_NULL)
-    s->check = (*s->checkfn)(s->check, q, n);
+    z->adler = s->check = (*s->checkfn)(s->check, q, n);

  /* copy as far as end of window */
  zmemcpy(p, q, n);
@@ -69,7 +69,7 @@ int r;

    /* update check information */
    if (s->checkfn != Z_NULL)
-      s->check = (*s->checkfn)(s->check, q, n);
+      z->adler = s->check = (*s->checkfn)(s->check, q, n);

    /* copy */
    zmemcpy(p, q, n);
--- a/infutil.h
+++ b/infutil.h
@@ -1,5 +1,5 @@
 /* infutil.h -- types and macros common to blocks and codes
- * Copyright (C) 1995 Mark Adler
+ * Copyright (C) 1995-1996 Mark Adler
 * For conditions of distribution and use, see copyright notice in zlib.h 
 */

@@ -8,11 +8,10 @@
   subject to change. Applications should only use zlib.h.
 */

-/* inflate blocks semi-private state */
-struct inflate_blocks_state {
+#ifndef _INFUTIL_H
+#define _INFUTIL_H

-  /* mode */
-  enum {
+typedef enum {
      TYPE,     /* get type bits (3, including end bit) */
      LENS,     /* get lengths for stored */
      STORED,   /* processing stored block */
@@ -23,7 +22,13 @@ struct inflate_blocks_state {
      DRY,      /* output remaining window bytes */
      DONE,     /* finished last block, done */
      BAD}      /* got a data error--stuck here */
-    mode;               /* current inflate_block mode */
+inflate_block_mode;
+
+/* inflate blocks semi-private state */
+struct inflate_blocks_state {
+
+  /* mode */
+  inflate_block_mode  mode;     /* current inflate_block mode */

  /* mode dependent information */
  union {
@@ -70,17 +75,17 @@ struct inflate_blocks_state {
 #define NEEDBITS(j) {while(k<(j)){NEEDBYTE;b|=((uLong)NEXTBYTE)<<k;k+=8;}}
 #define DUMPBITS(j) {b>>=(j);k-=(j);}
 /*   output bytes */
-#define WAVAIL (q<s->read?s->read-q-1:s->end-q)
-#define LOADOUT {q=s->write;m=WAVAIL;}
-#define WRAP {if(q==s->end&&s->read!=s->window){q=s->window;m=WAVAIL;}}
+#define WAVAIL (uInt)(q<s->read?s->read-q-1:s->end-q)
+#define LOADOUT {q=s->write;m=(uInt)WAVAIL;}
+#define WRAP {if(q==s->end&&s->read!=s->window){q=s->window;m=(uInt)WAVAIL;}}
 #define FLUSH {UPDOUT r=inflate_flush(s,z,r); LOADOUT}
 #define NEEDOUT {if(m==0){WRAP if(m==0){FLUSH WRAP if(m==0) LEAVE}}r=Z_OK;}
 #define OUTBYTE(a) {*q++=(Byte)(a);m--;}
 /*   load local pointers */
 #define LOAD {LOADIN LOADOUT}

-/* masks for lower bits */
-extern uInt inflate_mask[];
+/* masks for lower bits (size given to avoid silly warnings with Visual C++) */
+extern uInt inflate_mask[17];

 /* copy as much as possible from the sliding window to the output area */
 extern int inflate_flush OF((
@@ -89,3 +94,5 @@ extern int inflate_flush OF((
    int));

 struct internal_state      {int dummy;}; /* for buggy compilers */
+
+#endif
--- a/minigzip.c
+++ b/minigzip.c
@@ -1,5 +1,5 @@
 /* minigzip.c -- simulate gzip using the zlib compression library
- * Copyright (C) 1995 Jean-loup Gailly.
+ * Copyright (C) 1995-1996 Jean-loup Gailly.
 * For conditions of distribution and use, see copyright notice in zlib.h 
 */

@@ -18,14 +18,13 @@
 #include <stdio.h>
 #include "zlib.h"

-#ifndef __GO32__
-extern void exit  OF((int));
-#endif
-extern int unlink OF((const char *));
-
 #ifdef STDC
 #  include <string.h>
+#  include <stdlib.h>
+#else
+   extern void exit  OF((int));
 #endif
+extern int unlink OF((const char *));

 #if defined(MSDOS) || defined(OS2) || defined(WIN32)
 #  include <fcntl.h>
@@ -53,7 +52,7 @@ extern int unlink OF((const char *));

 char *prog;

-void error           OF((char *msg));
+void error           OF((const char *msg));
 void gz_compress     OF((FILE   *in, gzFile out));
 void gz_uncompress   OF((gzFile in, FILE   *out));
 void file_compress   OF((char  *file));
@@ -64,7 +63,7 @@ int  main            OF((int argc, char *argv[]));
 * Display error message and exit
 */
 void error(msg)
-    char *msg;
+    const char *msg;
 {
    fprintf(stderr, "%s: %s\n", prog, msg);
    exit(1);
@@ -89,7 +88,7 @@ void gz_compress(in, out)
        }
        if (len == 0) break;

-        if (gzwrite(out, buf, len) != len) error(gzerror(out, &err));
+        if (gzwrite(out, buf, (unsigned)len) != len) error(gzerror(out, &err));
    }
    fclose(in);
    if (gzclose(out) != Z_OK) error("failed gzclose");
@@ -111,7 +110,9 @@ void gz_uncompress(in, out)
        if (len < 0) error (gzerror(in, &err));
        if (len == 0) break;

-        if (fwrite(buf, 1, len, out) != (uInt)len) error("failed fwrite");
+        if ((int)fwrite(buf, 1, (unsigned)len, out) != len) {
+	    error("failed fwrite");
+	}
    }
    if (fclose(out)) error("failed fclose");

--- a/trees.c
+++ b/trees.c
@@ -1,5 +1,5 @@
 /* trees.c -- output deflated data using Huffman coding
- * Copyright (C) 1995 Jean-loup Gailly
+ * Copyright (C) 1995-1996 Jean-loup Gailly
 * For conditions of distribution and use, see copyright notice in zlib.h 
 */

@@ -78,13 +78,12 @@ local uch bl_order[BL_CODES]

 /* ===========================================================================
 * Local data. These are initialized only once.
- * To do: initialize at compile time to be completely reentrant. ???
 */

 local ct_data static_ltree[L_CODES+2];
 /* The static literal tree. Since the bit lengths are imposed, there is no
 * need for the L_CODES extra codes used during heap construction. However
- * The codes 286 and 287 are needed to build a canonical tree (see ct_init
+ * The codes 286 and 287 are needed to build a canonical tree (see _tr_init
 * below).
 */

@@ -129,7 +128,7 @@ local static_tree_desc  static_bl_desc =
 * Local (static) routines in this file.
 */

-local void ct_static_init OF((void));
+local void tr_static_init OF((void));
 local void init_block     OF((deflate_state *s));
 local void pqdownheap     OF((deflate_state *s, ct_data *tree, int k));
 local void gen_bitlen     OF((deflate_state *s, tree_desc *desc));
@@ -187,7 +186,7 @@ local void send_bits(s, value, length)
    int value;  /* value to send */
    int length; /* number of bits */
 {
-    Tracev((stderr," l %2d v %4x ", length, value));
+    Tracevv((stderr," l %2d v %4x ", length, value));
    Assert(length > 0 && length <= 15, "invalid length");
    s->bits_sent += (ulg)length;

@@ -227,11 +226,13 @@ local void send_bits(s, value, length)
 /* the arguments must not have side effects */

 /* ===========================================================================
- * Initialize the various 'constant' tables.
- * To do: do this at compile time.
+ * Initialize the various 'constant' tables. In a multi-threaded environment,
+ * this function may be called by two threads concurrently, but this is
+ * harmless since both invocations do exactly the same thing.
 */
-local void ct_static_init()
+local void tr_static_init()
 {
+    static static_init_done = 0;
    int n;        /* iterates over tree elements */
    int bits;     /* bit counter */
    int length;   /* length value */
@@ -240,6 +241,8 @@ local void ct_static_init()
    ush bl_count[MAX_BITS+1];
    /* number of codes at each bit length for an optimal tree */

+    if (static_init_done) return;
+
    /* Initialize the mapping length (0..255) -> length code (0..28) */
    length = 0;
    for (code = 0; code < LENGTH_CODES-1; code++) {
@@ -248,7 +251,7 @@ local void ct_static_init()
            length_code[length++] = (uch)code;
        }
    }
-    Assert (length == 256, "ct_static_init: length != 256");
+    Assert (length == 256, "tr_static_init: length != 256");
    /* Note that the length 255 (match length 258) can be represented
     * in two different ways: code 284 + 5 bits or code 285, so we
     * overwrite length_code[255] to use the best encoding:
@@ -263,7 +266,7 @@ local void ct_static_init()
            dist_code[dist++] = (uch)code;
        }
    }
-    Assert (dist == 256, "ct_static_init: dist != 256");
+    Assert (dist == 256, "tr_static_init: dist != 256");
    dist >>= 7; /* from now on, all distances are divided by 128 */
    for ( ; code < D_CODES; code++) {
        base_dist[code] = dist << 7;
@@ -271,7 +274,7 @@ local void ct_static_init()
            dist_code[256 + dist++] = (uch)code;
        }
    }
-    Assert (dist == 256, "ct_static_init: 256+dist != 512");
+    Assert (dist == 256, "tr_static_init: 256+dist != 512");

    /* Construct the codes of the static literal tree */
    for (bits = 0; bits <= MAX_BITS; bits++) bl_count[bits] = 0;
@@ -289,19 +292,18 @@ local void ct_static_init()
    /* The static distance tree is trivial: */
    for (n = 0; n < D_CODES; n++) {
        static_dtree[n].Len = 5;
-        static_dtree[n].Code = bi_reverse(n, 5);
+        static_dtree[n].Code = bi_reverse((unsigned)n, 5);
    }
+    static_init_done = 1;
 }

 /* ===========================================================================
 * Initialize the tree data structures for a new zlib stream.
 */
-void ct_init(s)
+void _tr_init(s)
    deflate_state *s;
 {
-    if (static_dtree[0].Len == 0) {
-        ct_static_init();              /* To do: at compile time */
-    }
+    tr_static_init();

    s->compressed_len = 0L;

@@ -523,7 +525,7 @@ local void gen_codes (tree, max_code, bl_count)
        /* Now reverse the bits */
        tree[n].Code = bi_reverse(next_code[len]++, len);

-        Tracec(tree != static_ltree, (stderr,"\nn %3d %c l %2d c %4x (%x) ",
+        Tracecv(tree != static_ltree, (stderr,"\nn %3d %c l %2d c %4x (%x) ",
             n, (isgraph(n) ? n : ' '), len, tree[n].Code, next_code[len]-1));
    }
 }
@@ -783,14 +785,14 @@ local void send_all_trees(s, lcodes, dcodes, blcodes)
 /* ===========================================================================
 * Send a stored block
 */
-void ct_stored_block(s, buf, stored_len, eof)
+void _tr_stored_block(s, buf, stored_len, eof)
    deflate_state *s;
    charf *buf;       /* input block */
    ulg stored_len;   /* length of input block */
    int eof;          /* true if this is the last block for a file */
 {
    send_bits(s, (STORED_BLOCK<<1)+eof, 3);  /* send block type */
-    s->compressed_len = (s->compressed_len + 3 + 7) & ~7L;
+    s->compressed_len = (s->compressed_len + 3 + 7) & (ulg)~7L;
    s->compressed_len += (stored_len + 4) << 3;

    copy_block(s, buf, (unsigned)stored_len, 1); /* with header */
@@ -799,12 +801,15 @@ void ct_stored_block(s, buf, stored_len, eof)
 /* ===========================================================================
 * Send one empty static block to give enough lookahead for inflate.
 * This takes 10 bits, of which 7 may remain in the bit buffer.
- * The current inflate code requires 9 bits of lookahead. If the EOB
- * code for the previous block was coded on 5 bits or less, inflate
- * may have only 5+3 bits of lookahead to decode this EOB.
- * (There are no problems if the previous block is stored or fixed.)
+ * The current inflate code requires 9 bits of lookahead. If the
+ * last two codes for the previous block (real code plus EOB) were coded
+ * on 5 bits or less, inflate may have only 5+3 bits of lookahead to decode
+ * the last real code. In this case we send two empty static blocks instead
+ * of one. (There are no problems if the previous block is stored or fixed.)
+ * To simplify the code, we assume the worst case of last real code encoded
+ * on one bit only.
 */
-void ct_align(s)
+void _tr_align(s)
    deflate_state *s;
 {
    send_bits(s, STATIC_TREES<<1, 3);
@@ -812,10 +817,11 @@ void ct_align(s)
    s->compressed_len += 10L; /* 3 for block type, 7 for EOB */
    bi_flush(s);
    /* Of the 10 bits for the empty block, we have already sent
-     * (10 - bi_valid) bits. The lookahead for the EOB of the previous
-     * block was thus its length plus what we have just sent.
+     * (10 - bi_valid) bits. The lookahead for the last real code (before
+     * the EOB of the previous block) was thus at least one plus the length
+     * of the EOB plus what we have just sent of the empty static block.
     */
-    if (s->last_eob_len + 10 - s->bi_valid < 9) {
+    if (1 + s->last_eob_len + 10 - s->bi_valid < 9) {
        send_bits(s, STATIC_TREES<<1, 3);
        send_code(s, END_BLOCK, static_ltree);
        s->compressed_len += 10L;
@@ -829,44 +835,52 @@ void ct_align(s)
 * trees or store, and output the encoded block to the zip file. This function
 * returns the total compressed length for the file so far.
 */
-ulg ct_flush_block(s, buf, stored_len, eof)
+ulg _tr_flush_block(s, buf, stored_len, eof)
    deflate_state *s;
    charf *buf;       /* input block, or NULL if too old */
    ulg stored_len;   /* length of input block */
    int eof;          /* true if this is the last block for a file */
 {
    ulg opt_lenb, static_lenb; /* opt_len and static_len in bytes */
-    int max_blindex;  /* index of last bit length code of non zero freq */
+    int max_blindex = 0;  /* index of last bit length code of non zero freq */

-     /* Check if the file is ascii or binary */
-    if (s->data_type == UNKNOWN) set_data_type(s);
+    /* Build the Huffman trees unless a stored block is forced */
+    if (s->level > 0) {

-    /* Construct the literal and distance trees */
-    build_tree(s, (tree_desc *)(&(s->l_desc)));
-    Tracev((stderr, "\nlit data: dyn %ld, stat %ld", s->opt_len,
-            s->static_len));
+	 /* Check if the file is ascii or binary */
+	if (s->data_type == Z_UNKNOWN) set_data_type(s);

-    build_tree(s, (tree_desc *)(&(s->d_desc)));
-    Tracev((stderr, "\ndist data: dyn %ld, stat %ld", s->opt_len,
-            s->static_len));
-    /* At this point, opt_len and static_len are the total bit lengths of
-     * the compressed block data, excluding the tree representations.
-     */
+	/* Construct the literal and distance trees */
+	build_tree(s, (tree_desc *)(&(s->l_desc)));
+	Tracev((stderr, "\nlit data: dyn %ld, stat %ld", s->opt_len,
+		s->static_len));

-    /* Build the bit length tree for the above two trees, and get the index
-     * in bl_order of the last bit length code to send.
-     */
-    max_blindex = build_bl_tree(s);
+	build_tree(s, (tree_desc *)(&(s->d_desc)));
+	Tracev((stderr, "\ndist data: dyn %ld, stat %ld", s->opt_len,
+		s->static_len));
+	/* At this point, opt_len and static_len are the total bit lengths of
+	 * the compressed block data, excluding the tree representations.
+	 */

-    /* Determine the best encoding. Compute first the block length in bytes */
-    opt_lenb = (s->opt_len+3+7)>>3;
-    static_lenb = (s->static_len+3+7)>>3;
+	/* Build the bit length tree for the above two trees, and get the index
+	 * in bl_order of the last bit length code to send.
+	 */
+	max_blindex = build_bl_tree(s);

-    Tracev((stderr, "\nopt %lu(%lu) stat %lu(%lu) stored %lu lit %u ",
-            opt_lenb, s->opt_len, static_lenb, s->static_len, stored_len,
-            s->last_lit));
+	/* Determine the best encoding. Compute first the block length in bytes*/
+	opt_lenb = (s->opt_len+3+7)>>3;
+	static_lenb = (s->static_len+3+7)>>3;

-    if (static_lenb <= opt_lenb) opt_lenb = static_lenb;
+	Tracev((stderr, "\nopt %lu(%lu) stat %lu(%lu) stored %lu lit %u ",
+		opt_lenb, s->opt_len, static_lenb, s->static_len, stored_len,
+		s->last_lit));
+
+	if (static_lenb <= opt_lenb) opt_lenb = static_lenb;
+
+    } else {
+        Assert(buf != (char*)0, "lost buf");
+	opt_lenb = static_lenb = stored_len + 5; /* force a stored block */
+    }

    /* If compression failed and this is the first and last block,
     * and if the .zip file can be seeked (to rewrite the local header),
@@ -874,7 +888,7 @@ ulg ct_flush_block(s, buf, stored_len, eof)
     */
 #ifdef STORED_FILE_OK
 #  ifdef FORCE_STORED_FILE
-    if (eof && compressed_len == 0L) { /* force stored file */
+    if (eof && s->compressed_len == 0L) { /* force stored file */
 #  else
    if (stored_len <= opt_lenb && eof && s->compressed_len==0L && seekable()) {
 #  endif
@@ -899,7 +913,7 @@ ulg ct_flush_block(s, buf, stored_len, eof)
         * successful. If LIT_BUFSIZE <= WSIZE, it is never too late to
         * transform a block into a stored block.
         */
-        ct_stored_block(s, buf, stored_len, eof);
+        _tr_stored_block(s, buf, stored_len, eof);

 #ifdef FORCE_STATIC
    } else if (static_lenb >= 0) { /* force static trees */
@@ -933,10 +947,10 @@ ulg ct_flush_block(s, buf, stored_len, eof)
 * Save the match info and tally the frequency counts. Return true if
 * the current block must be flushed.
 */
-int ct_tally (s, dist, lc)
+int _tr_tally (s, dist, lc)
    deflate_state *s;
-    int dist;  /* distance of matched string */
-    int lc;    /* match length-MIN_MATCH or unmatched char (if dist==0) */
+    unsigned dist;  /* distance of matched string */
+    unsigned lc;    /* match length-MIN_MATCH or unmatched char (if dist==0) */
 {
    s->d_buf[s->last_lit] = (ush)dist;
    s->l_buf[s->last_lit++] = (uch)lc;
@@ -949,7 +963,7 @@ int ct_tally (s, dist, lc)
        dist--;             /* dist = match distance - 1 */
        Assert((ush)dist < (ush)MAX_DIST(s) &&
               (ush)lc <= (ush)(MAX_MATCH-MIN_MATCH) &&
-               (ush)d_code(dist) < (ush)D_CODES,  "ct_tally: bad match");
+               (ush)d_code(dist) < (ush)D_CODES,  "_tr_tally: bad match");

        s->dyn_ltree[length_code[lc]+LITERALS+1].Freq++;
        s->dyn_dtree[d_code(dist)].Freq++;
@@ -959,7 +973,7 @@ int ct_tally (s, dist, lc)
    if (s->level > 2 && (s->last_lit & 0xfff) == 0) {
        /* Compute an upper bound for the compressed length */
        ulg out_length = (ulg)s->last_lit*8L;
-        ulg in_length = (ulg)s->strstart - s->block_start;
+        ulg in_length = (ulg)((long)s->strstart - s->block_start);
        int dcode;
        for (dcode = 0; dcode < D_CODES; dcode++) {
            out_length += (ulg)s->dyn_dtree[dcode].Freq *
@@ -1043,7 +1057,7 @@ local void set_data_type(s)
    while (n < 7)        bin_freq += s->dyn_ltree[n++].Freq;
    while (n < 128)    ascii_freq += s->dyn_ltree[n++].Freq;
    while (n < LITERALS) bin_freq += s->dyn_ltree[n++].Freq;
-    s->data_type = (Byte)(bin_freq > (ascii_freq >> 2) ? BINARY : ASCII);
+    s->data_type = (Byte)(bin_freq > (ascii_freq >> 2) ? Z_BINARY : Z_ASCII);
 }

 /* ===========================================================================
--- a/uncompr.c
+++ b/uncompr.c
@@ -1,5 +1,5 @@
 /* uncompr.c -- decompress a memory buffer
- * Copyright (C) 1995 Jean-loup Gailly.
+ * Copyright (C) 1995-1996 Jean-loup Gailly.
 * For conditions of distribution and use, see copyright notice in zlib.h 
 */

@@ -25,13 +25,13 @@
 int uncompress (dest, destLen, source, sourceLen)
    Bytef *dest;
    uLongf *destLen;
-    Bytef *source;
+    const Bytef *source;
    uLong sourceLen;
 {
    z_stream stream;
    int err;

-    stream.next_in = source;
+    stream.next_in = (Bytef*)source;
    stream.avail_in = (uInt)sourceLen;
    /* Check for source > 64K on 16-bit machine: */
    if ((uLong)stream.avail_in != sourceLen) return Z_BUF_ERROR;
--- a/zconf.h
+++ b/zconf.h
@@ -1,5 +1,5 @@
 /* zconf.h -- configuration of the zlib compression library
- * Copyright (C) 1995 Jean-loup Gailly.
+ * Copyright (C) 1995-1996 Jean-loup Gailly.
 * For conditions of distribution and use, see copyright notice in zlib.h 
 */

@@ -9,22 +9,55 @@
 #define _ZCONF_H

 /*
-     The library does not install any signal handler. It is recommended to
-  add at least a handler for SIGSEGV when decompressing; the library checks
-  the consistency of the input data whenever possible but may go nuts
-  for some forms of corrupted input.
+ * People prefering a unique prefix for all types and library functions
+ * should compile with -DZ_PREFIX
 */
+#ifdef Z_PREFIX
+#  define deflateInit_	z_deflateInit_
+#  define deflate	z_deflate
+#  define deflateEnd	z_deflateEnd
+#  define inflateInit_ 	z_inflateInit_
+#  define inflate	z_inflate
+#  define inflateEnd	z_inflateEnd
+#  define deflateInit2_	z_deflateInit2_
+#  define deflateCopy	z_deflateCopy
+#  define deflateReset	z_deflateReset
+#  define deflateParams	z_deflateParams
+#  define inflateInit2_	z_inflateInit2_
+#  define inflateSync	z_inflateSync
+#  define inflateReset	z_inflateReset
+#  define compress	z_compress
+#  define uncompress	z_uncompress
+#  define adler32	z_adler32
+#  define crc32		z_crc32
+#  define get_crc_table z_get_crc_table

-/*
- * Compile with -DMAXSEG_64K if the alloc function cannot allocate more
- * than 64k bytes at a time (needed on systems with 16-bit int).
- */
-#if defined(_GNUC__) && !defined(__32BIT__)
+#  define Byte		z_Byte
+#  define uInt		z_uInt
+#  define uLong		z_uLong
+#  define Bytef		z_Bytef
+#  define charf		z_charf
+#  define intf		z_intf
+#  define uIntf		z_uIntf
+#  define uLongf	z_uLongf
+#  define voidpf	z_voidpf
+#  define voidp		z_voidp
+#endif
+
+#if (defined(_WIN32) || defined(__WIN32__)) && !defined(WIN32)
+#  define WIN32
+#endif
+#if (defined(__GNUC__) || defined(WIN32)) && !defined(__32BIT__)
 #  define __32BIT__
 #endif
 #if defined(__MSDOS__) && !defined(MSDOS)
 #  define MSDOS
 #endif
+
+/*
+ * Compile with -DMAXSEG_64K if the alloc function cannot allocate more
+ * than 64k bytes at a time (needed on systems with 16-bit int).
+ */
 #if defined(MSDOS) && !defined(__32BIT__)
 #  define MAXSEG_64K
 #endif
@@ -32,20 +65,20 @@
 #  define UNALIGNED_OK
 #endif

-#ifndef STDC
-#  if defined(MSDOS) || defined(__STDC__) || defined(__cplusplus)
-#    define STDC
-#  endif
+#if (defined(MSDOS) || defined(_WINDOWS) || defined(WIN32))  && !defined(STDC)
+#  define STDC
+#endif
+#if (defined(__STDC__) || defined(__cplusplus)) && !defined(STDC)
+#  define STDC
 #endif

-#ifndef STDC
-#  ifndef const
-#    define const
-#  endif
+#if !defined(STDC) && !defined(const)
+#  define const
 #endif

 #ifdef	__MWERKS__ /* Metrowerks CodeWarrior declares fileno() in unix.h */
 #  include <unix.h>
+#  define Byte _Byte /* Byte already used on Mac */
 #endif

 /* Maximum value for memLevel in deflateInit2 */
@@ -92,6 +125,7 @@
 * just define FAR to be empty.
 */
 #if defined(M_I86SM) || defined(M_I86MM) /* MSC small or medium model */
+#  define SMALL_MEDIUM
 #  ifdef _MSC_VER
 #    define FAR __far
 #  else
@@ -99,20 +133,26 @@
 #  endif
 #endif
 #if defined(__BORLANDC__) && (defined(__SMALL__) || defined(__MEDIUM__))
-#    define FAR __far /* completely untested, just a best guess */
+#    define SMALL_MEDIUM
+#    define FAR __far
 #endif
 #ifndef FAR
 #   define FAR
 #endif
+/* The Watcom compiler defines M_I86SM and __SMALL__ even in 32 bit mode */
+#if defined(__WATCOMC__) && defined(__386__)
+#  undef FAR
+#  undef SMALL_MEDIUM
+#endif

 typedef unsigned char  Byte;  /* 8 bits */
 typedef unsigned int   uInt;  /* 16 bits or more */
 typedef unsigned long  uLong; /* 32 bits or more */

-typedef Byte FAR Bytef;
-typedef char FAR charf;
-typedef int FAR intf;
-typedef uInt FAR uIntf;
+typedef Byte  FAR Bytef;
+typedef char  FAR charf;
+typedef int   FAR intf;
+typedef uInt  FAR uIntf;
 typedef uLong FAR uLongf;

 #ifdef STDC
--- a/zlib.h
+++ b/zlib.h
@@ -1,7 +1,7 @@
 /* zlib.h -- interface of the 'zlib' general purpose compression library
-  version 0.95, Aug 16th, 1995.
+  version 1.0, Jan 27th, 1996.

-  Copyright (C) 1995 Jean-loup Gailly and Mark Adler
+  Copyright (C) 1995-1996 Jean-loup Gailly and Mark Adler

  This software is provided 'as-is', without any express or implied
  warranty.  In no event will the authors be held liable for any damages
@@ -26,9 +26,13 @@
 #ifndef _ZLIB_H
 #define _ZLIB_H

+#ifdef __cplusplus
+extern "C" {
+#endif
+
 #include "zconf.h"

-#define ZLIB_VERSION "0.95"
+#define ZLIB_VERSION "1.0"

 /* 
     The 'zlib' compression library provides in-memory compression and
@@ -47,6 +51,11 @@
  repeated calls of the compression function.  In the latter case, the
  application must provide more input and/or consume the output
  (providing more output space) before each call.
+
+     The library does not install any signal handler. It is recommended to
+  add at least a handler for SIGSEGV when decompressing; the library checks
+  the consistency of the input data whenever possible but may go nuts
+  for some forms of corrupted input.
 */

 typedef voidpf (*alloc_func) OF((voidpf opaque, uInt items, uInt size));
@@ -68,10 +77,11 @@ typedef struct z_stream_s {

    alloc_func zalloc;  /* used to allocate the internal state */
    free_func  zfree;   /* used to free the internal state */
-    voidp      opaque;  /* private data object passed to zalloc and zfree */
-
-    Byte     data_type; /* best guess about the data type: ascii or binary */
+    voidpf     opaque;  /* private data object passed to zalloc and zfree */

+    int     data_type;  /* best guess about the data type: ascii or binary */
+    uLong   adler;      /* adler32 value of the uncompressed data */
+    uLong   reserved;   /* reserved for future use */
 } z_stream;

 /*
@@ -107,20 +117,25 @@ typedef struct z_stream_s {

 #define Z_NO_FLUSH      0
 #define Z_PARTIAL_FLUSH 1
-#define Z_FULL_FLUSH    2
-#define Z_SYNC_FLUSH    3 /* experimental: partial_flush + byte align */
+#define Z_SYNC_FLUSH    2
+#define Z_FULL_FLUSH    3
 #define Z_FINISH        4
-/* See deflate() below for the usage of these constants */
+/* Allowed flush values; see deflate() below for details */

 #define Z_OK            0
 #define Z_STREAM_END    1
+#define Z_NEED_DICT     2
 #define Z_ERRNO        (-1)
 #define Z_STREAM_ERROR (-2)
 #define Z_DATA_ERROR   (-3)
 #define Z_MEM_ERROR    (-4)
 #define Z_BUF_ERROR    (-5)
-/* error codes for the compression/decompression functions */
+#define Z_VERSION_ERROR (-6)
+/* Return codes for the compression/decompression functions. Negative
+ * values are errors, positive values are used for special but normal events.
+ */

+#define Z_NO_COMPRESSION         0
 #define Z_BEST_SPEED             1
 #define Z_BEST_COMPRESSION       9
 #define Z_DEFAULT_COMPRESSION  (-1)
@@ -129,15 +144,19 @@ typedef struct z_stream_s {
 #define Z_FILTERED            1
 #define Z_HUFFMAN_ONLY        2
 #define Z_DEFAULT_STRATEGY    0
+/* compression strategy; see deflateInit2() below for details */

 #define Z_BINARY   0
 #define Z_ASCII    1
 #define Z_UNKNOWN  2
-/* Used to set the data_type field */
+/* Possible values of the data_type field */
+
+#define Z_DEFLATED   8
+/* The deflate compression method (the only one supported in this version) */

 #define Z_NULL  0  /* for initializing zalloc, zfree, opaque */

-extern char *zlib_version;
+extern const char *zlib_version;
 /* The application can compare zlib_version and ZLIB_VERSION for consistency.
   If the first character differs, the library code actually used is
   not compatible with the zlib.h header file used by the application.
@@ -145,20 +164,24 @@ extern char *zlib_version;

                        /* basic functions */

-extern int deflateInit OF((z_stream *strm, int level));
 /* 
+extern int deflateInit OF((z_stream *strm, int level));
+
     Initializes the internal stream state for compression. The fields
   zalloc, zfree and opaque must be initialized before by the caller.
   If zalloc and zfree are set to Z_NULL, deflateInit updates them to
   use default allocation functions.

-     The compression level must be Z_DEFAULT_COMPRESSION, or between 1 and 9:
-   1 gives best speed, 9 gives best compression. Z_DEFAULT_COMPRESSION requests
-   a default compromise between speed and compression (currently equivalent
-   to level 6).
+     The compression level must be Z_DEFAULT_COMPRESSION, or between 0 and 9:
+   1 gives best speed, 9 gives best compression, 0 gives no compression at
+   all (the input data is simply copied a block at a time).
+   Z_DEFAULT_COMPRESSION requests a default compromise between speed and
+   compression (currently equivalent to level 6).

     deflateInit returns Z_OK if success, Z_MEM_ERROR if there was not
-   enough memory, Z_STREAM_ERROR if level is not a valid compression level.
+   enough memory, Z_STREAM_ERROR if level is not a valid compression level,
+   Z_VERSION_ERROR if the zlib library version (zlib_version) is incompatible
+   with the version assumed by the caller (ZLIB_VERSION).
   msg is set to null if there is no error message.  deflateInit does not
   perform any compression: this will be done by deflate().
 */
@@ -190,7 +213,12 @@ extern int deflate OF((z_stream *strm, int flush));
  block is terminated and flushed to the output buffer so that the
  decompressor can get all input data available so far. For method 9, a future
  variant on method 8, the current block will be flushed but not terminated.
-  If flush is set to Z_FULL_FLUSH, the compression block is terminated, a
+  Z_SYNC_FLUSH has the same effect as partial flush except that the compressed
+  output is byte aligned (the compressor can clear its internal bit buffer)
+  and the current block is always terminated; this can be useful if the
+  compressor has to be restarted from scratch after an interruption (in which
+  case the internal state of the compressor may be lost).
+    If flush is set to Z_FULL_FLUSH, the compression block is terminated, a
  special marker is output and the compression dictionary is discarded; this
  is useful to allow the decompressor to synchronize if one compressed block
  has been damaged (see inflateSync below).  Flushing degrades compression and
@@ -233,22 +261,26 @@ extern int deflateEnd OF((z_stream *strm));
   pending output.

     deflateEnd returns Z_OK if success, Z_STREAM_ERROR if the
-   stream state was inconsistent. In the error case, msg may be set
-   but then points to a static string (which must not be deallocated).
+   stream state was inconsistent, Z_DATA_ERROR if the stream was freed
+   prematurely (some input or output was discarded). In the error case,
+   msg may be set but then points to a static string (which must not be
+   deallocated).
 */


-extern int inflateInit OF((z_stream *strm));
 /* 
+extern int inflateInit OF((z_stream *strm));
+
     Initializes the internal stream state for decompression. The fields
-   zalloc and zfree must be initialized before by the caller.  If zalloc and
-   zfree are set to Z_NULL, inflateInit updates them to use default allocation
-   functions.
+   zalloc, zfree and opaque must be initialized before by the caller.  If
+   zalloc and zfree are set to Z_NULL, inflateInit updates them to use default
+   allocation functions.

     inflateInit returns Z_OK if success, Z_MEM_ERROR if there was not
-   enough memory.  msg is set to null if there is no error message.
-   inflateInit does not perform any decompression: this will be done by
-   inflate().
+   enough memory, Z_VERSION_ERROR if the zlib library version is incompatible
+   with the version assumed by the caller.  msg is set to null if there is no
+   error message. inflateInit does not perform any decompression: this will be
+   done by inflate().
 */


@@ -292,12 +324,15 @@ extern int inflate OF((z_stream *strm, int flush));
    inflate() returns Z_OK if some progress has been made (more input
  processed or more output produced), Z_STREAM_END if the end of the
  compressed data has been reached and all uncompressed output has been
-  produced, Z_DATA_ERROR if the input data was corrupted, Z_STREAM_ERROR if
-  the stream structure was inconsistent (for example if next_in or next_out
-  was NULL), Z_MEM_ERROR if there was not enough memory, Z_BUF_ERROR if no
-  progress is possible or if there was not enough room in the output buffer
-  when Z_FINISH is used. In the Z_DATA_ERROR case, the application may then
-  call inflateSync to look for a good compression block.
+  produced, Z_NEED_DICT if a preset dictionary is needed at this point (see
+  inflateSetDictionary below), Z_DATA_ERROR if the input data was corrupted,
+  Z_STREAM_ERROR if the stream structure was inconsistent (for example if
+  next_in or next_out was NULL), Z_MEM_ERROR if there was not enough memory,
+  Z_BUF_ERROR if no progress is possible or if there was not enough room in
+  the output buffer when Z_FINISH is used. In the Z_DATA_ERROR case, the
+  application may then call inflateSync to look for a good compression block.
+  In the Z_NEED_DICT case, strm->adler is set to the Adler32 value of the
+  dictionary chosen by the compressor.
 */


@@ -312,24 +347,26 @@ extern int inflateEnd OF((z_stream *strm));
   static string (which must not be deallocated).
 */

-                        /* advanced functions */
+                        /* Advanced functions */

 /*
    The following functions are needed only in some special applications.
 */

+/*   
 extern int deflateInit2 OF((z_stream *strm,
                            int  level,
                            int  method,
                            int  windowBits,
                            int  memLevel,
                            int  strategy));
-/*   
-     This is another version of deflateInit with more compression options. The
-   fields next_in, zalloc and zfree must be initialized before by the caller.

-     The method parameter is the compression method. It must be 8 in this
-   version of the library. (Method 9 will allow a 64K history buffer and
+     This is another version of deflateInit with more compression options. The
+   fields next_in, zalloc, zfree and opaque must be initialized before by
+   the caller.
+
+     The method parameter is the compression method. It must be Z_DEFLATED in
+   this version of the library. (Method 9 will allow a 64K history buffer and
   partial block flushes.)

     The windowBits parameter is the base two logarithm of the window size
@@ -338,20 +375,22 @@ extern int deflateInit2 OF((z_stream *strm,
   values of this parameter result in better compression at the expense of
   memory usage. The default value is 15 if deflateInit is used instead.

-    The memLevel parameter specifies how much memory should be allocated
+     The memLevel parameter specifies how much memory should be allocated
   for the internal compression state. memLevel=1 uses minimum memory but
   is slow and reduces compression ratio; memLevel=9 uses maximum memory
   for optimal speed. The default value is 8. See zconf.h for total memory
   usage as a function of windowBits and memLevel.

-     The strategy parameter is used to tune the compression algorithm. Use
-   the value Z_DEFAULT_STRATEGY for normal data, Z_FILTERED for data
-   produced by a filter (or predictor), or Z_HUFFMAN_ONLY to force Huffman
-   encoding only (no string match).  Filtered data consists mostly of small
-   values with a somewhat random distribution. In this case, the
-   compression algorithm is tuned to compress them better. The strategy
-   parameter only affects the compression ratio but not the correctness of
-   the compressed output even if it is not set appropriately.
+     The strategy parameter is used to tune the compression algorithm. Use the
+   value Z_DEFAULT_STRATEGY for normal data, Z_FILTERED for data produced by a
+   filter (or predictor), or Z_HUFFMAN_ONLY to force Huffman encoding only (no
+   string match).  Filtered data consists mostly of small values with a
+   somewhat random distribution. In this case, the compression algorithm is
+   tuned to compress them better. The effect of Z_FILTERED is to force more
+   Huffman coding and less string matching; it is somewhat intermediate
+   between Z_DEFAULT and Z_HUFFMAN_ONLY. The strategy parameter only affects
+   the compression ratio but not the correctness of the compressed output even
+   if it is not set appropriately.

     If next_in is not null, the library will use this buffer to hold also
   some history information; the buffer must either hold the entire input
@@ -373,6 +412,35 @@ extern int deflateInit2 OF((z_stream *strm,
   deflate(). 
 */
                            
+extern int deflateSetDictionary OF((z_stream *strm,
+				    const Bytef *dictionary,
+				    uInt  dictLength));
+/*
+     Initializes the compression dictionary (history buffer) from the given
+   byte sequence without producing any compressed output. This function must
+   be called immediately after deflateInit or deflateInit2, before any call
+   of deflate. The compressor and decompressor must use exactly the same
+   dictionary (see inflateSetDictionary).
+     The dictionary should consist of strings (byte sequences) that are likely
+   to be encountered later in the data to be compressed, with the most commonly
+   used strings preferably put towards the end of the dictionary. Using a
+   dictionary is most useful when the data to be compressed is short and
+   can be predicted with good accuracy; the data can then be compressed better
+   than with the default empty dictionary. In this version of the library,
+   only the last 32K bytes of the dictionary are used.
+     Upon return of this function, strm->adler is set to the Adler32 value
+   of the dictionary; the decompressor may later use this value to determine
+   which dictionary has been used by the compressor. (The Adler32 value
+   applies to the whole dictionary even if only a subset of the dictionary is
+   actually used by the compressor.)
+
+     deflateSetDictionary returns Z_OK if success, or Z_STREAM_ERROR if a
+   parameter is invalid (such as NULL dictionary) or the stream state
+   is inconsistent (for example if deflate has already been called for this
+   stream). deflateSetDictionary does not perform any compression: this will
+   be done by deflate(). 
+*/
+
 extern int deflateCopy OF((z_stream *dest,
                           z_stream *source));
 /*
@@ -383,14 +451,14 @@ extern int deflateCopy OF((z_stream *dest,
   application to provide the correct values of next_out and avail_out for the
   next call of deflate.

-     This function is useful when several compression strategies will be
+     This function can be useful when several compression strategies will be
   tried, for example when there are several ways of pre-processing the input
   data with a filter. The streams that will be discarded should then be freed
   by calling deflateEnd.  Note that deflateCopy duplicates the internal
   compression state which can be quite large, so this strategy is slow and
   can consume lots of memory.

-      deflateCopy returns Z_OK if success, Z_MEM_ERROR if there was not
+     deflateCopy returns Z_OK if success, Z_MEM_ERROR if there was not
   enough memory, Z_STREAM_ERROR if the source stream state was inconsistent
   (such as zalloc being NULL). msg is left unchanged in both source and
   destination.
@@ -407,11 +475,26 @@ extern int deflateReset OF((z_stream *strm));
   stream state was inconsistent (such as zalloc or state being NULL).
 */

+extern int deflateParams OF((z_stream *strm, int level, int strategy));
+/*
+     Dynamically update the compression level and compression strategy.
+   This can be used to switch between compression and straight copy of
+   the input data, or to switch to a different kind of input data requiring
+   a different strategy. If the compression level is changed, the input
+   available so far is compressed with the old level (and may be flushed);
+   the new level will take effect only at the next call of deflate().
+
+     deflateParams returns Z_OK if success, Z_STREAM_ERROR if the source
+   stream state was inconsistent or if a parameter was invalid.
+*/
+
+/*   
 extern int inflateInit2 OF((z_stream *strm,
                            int  windowBits));
-/*   
+
     This is another version of inflateInit with more compression options. The
-   fields next_out, zalloc and zfree must be initialized before by the caller.
+   fields next_out, zalloc, zfree and opaque must be initialized before by
+   the caller.

     The windowBits parameter is the base two logarithm of the maximum window
   size (the size of the history buffer).  It should be in the range 8..15 for
@@ -440,6 +523,25 @@ extern int inflateInit2 OF((z_stream *strm,
   inflate().
 */

+extern int inflateSetDictionary OF((z_stream *strm,
+				    const Bytef *dictionary,
+				    uInt  dictLength));
+/*
+     Initializes the decompression dictionary (history buffer) from the given
+   uncompressed byte sequence. This function must be called immediately after
+   a call of inflate if this call returned Z_NEED_DICT. The dictionary chosen
+   by the compressor can be determined from the Adler32 value returned by this
+   call of inflate. The compressor and decompressor must use exactly the same
+   dictionary (see deflateSetDictionary).
+
+     inflateSetDictionary returns Z_OK if success, Z_STREAM_ERROR if a
+   parameter is invalid (such as NULL dictionary) or the stream state is
+   inconsistent, Z_DATA_ERROR if the given dictionary doesn't match the
+   expected one (incorrect Adler32 value). inflateSetDictionary does not
+   perform any decompression: this will be done by subsequent calls of
+   inflate().
+*/
+
 extern int inflateSync OF((z_stream *strm));
 /* 
    Skips invalid compressed data until the special marker (see deflate()
@@ -477,7 +579,7 @@ extern int inflateReset OF((z_stream *strm));
 */

 extern int compress OF((Bytef *dest,   uLongf *destLen,
-                        Bytef *source, uLong sourceLen));
+                        const Bytef *source, uLong sourceLen));
 /*
     Compresses the source buffer into the destination buffer.  sourceLen is
   the byte length of the source buffer. Upon entry, destLen is the total
@@ -492,7 +594,7 @@ extern int compress OF((Bytef *dest,   uLongf *destLen,
 */

 extern int uncompress OF((Bytef *dest,   uLongf *destLen,
-                          Bytef *source, uLong sourceLen));
+                          const Bytef *source, uLong sourceLen));
 /*
     Decompresses the source buffer into the destination buffer.  sourceLen is
   the byte length of the source buffer. Upon entry, destLen is the total
@@ -512,7 +614,7 @@ extern int uncompress OF((Bytef *dest,   uLongf *destLen,

 typedef voidp gzFile;

-extern gzFile gzopen  OF((char *path, char *mode));
+extern gzFile gzopen  OF((const char *path, const char *mode));
 /*
     Opens a gzip (.gz) file for reading or writing. The mode parameter
   is as in fopen ("rb" or "wb") but can also include a compression level
@@ -524,11 +626,15 @@ extern gzFile gzopen  OF((char *path, char *mode));
   zlib error is Z_MEM_ERROR).
 */

-extern gzFile gzdopen  OF((int fd, char *mode));
+extern gzFile gzdopen  OF((int fd, const char *mode));
 /*
     gzdopen() associates a gzFile with the file descriptor fd.  File
-   descriptors are obtained from calls like open, dup, creat, or pipe.
+   descriptors are obtained from calls like open, dup, creat, pipe or
+   fileno (in the file has been previously opened with fopen).
   The mode parameter is as in fopen ("rb" or "wb").
+     The next call of gzclose on the returned gzFile will also close the
+   file descriptor fd, just like fclose(fdopen(fd), mode) closes the file
+   descriptor fd. If you want to keep fd open, use gzdopen(dup(fd), mode).
     gzdopen returns NULL if there was insufficient memory to allocate
   the (de)compression state.
 */
@@ -541,7 +647,7 @@ extern int    gzread  OF((gzFile file, voidp buf, unsigned len));
     gzread returns the number of uncompressed bytes actually read (0 for
   end of file, -1 for error). */

-extern int    gzwrite OF((gzFile file, voidp buf, unsigned len));
+extern int    gzwrite OF((gzFile file, const voidp buf, unsigned len));
 /*
     Writes the given number of uncompressed bytes into the compressed file.
   gzwrite returns the number of uncompressed bytes actually written
@@ -582,7 +688,7 @@ extern char*   gzerror OF((gzFile file, int *errnum));
   compression library.
 */

-extern uLong adler32 OF((uLong adler, Bytef *buf, uInt len));
+extern uLong adler32 OF((uLong adler, const Bytef *buf, uInt len));

 /*
     Update a running Adler-32 checksum with the bytes buf[0..len-1] and
@@ -599,7 +705,7 @@ extern uLong adler32 OF((uLong adler, Bytef *buf, uInt len));
     if (adler != original_adler) error();
 */

-extern uLong crc32   OF((uLong crc, Bytef *buf, uInt len));
+extern uLong crc32   OF((uLong crc, const Bytef *buf, uInt len));
 /*
     Update a running crc with the bytes buf[0..len-1] and return the updated
   crc. If buf is NULL, this function returns the required initial value
@@ -615,8 +721,39 @@ extern uLong crc32   OF((uLong crc, Bytef *buf, uInt len));
     if (crc != original_crc) error();
 */

+
+                        /* various hacks, don't look :) */
+
+/* deflateInit and inflateInit are macros to allow checking the zlib version
+ * and the compiler's view of z_stream:
+ */
+extern int deflateInit_ OF((z_stream *strm, int level,
+			    const char *version, int stream_size));
+extern int inflateInit_ OF((z_stream *strm,
+			    const char *version, int stream_size));
+extern int deflateInit2_ OF((z_stream *strm, int  level, int  method,
+                             int  windowBits, int  memLevel, int  strategy,
+			     const char *version, int stream_size));
+extern int inflateInit2_ OF((z_stream *strm, int  windowBits,
+			     const char *version, int stream_size));
+#define deflateInit(strm, level) \
+        deflateInit_((strm), (level),       ZLIB_VERSION, sizeof(z_stream))
+#define inflateInit(strm) \
+        inflateInit_((strm),                ZLIB_VERSION, sizeof(z_stream))
+#define deflateInit2(strm, level, method, windowBits, memLevel, strategy) \
+        deflateInit2_((strm),(level),(method),(windowBits),(memLevel),\
+		      (strategy),           ZLIB_VERSION, sizeof(z_stream))
+#define inflateInit2(strm, windowBits) \
+        inflateInit2_((strm), (windowBits), ZLIB_VERSION, sizeof(z_stream))
+
 #ifndef _Z_UTIL_H
    struct internal_state {int dummy;}; /* hack for buggy compilers */
 #endif

+uLongf *get_crc_table OF((void)); /* can be used by asm versions of crc32() */
+
+#ifdef __cplusplus
+}
+#endif
+
 #endif /* _ZLIB_H */
--- a/zutil.c
+++ b/zutil.c
@@ -1,5 +1,5 @@
 /* zutil.c -- target dependent utility functions for the compression library
- * Copyright (C) 1995 Jean-loup Gailly.
+ * Copyright (C) 1995-1996 Jean-loup Gailly.
 * For conditions of distribution and use, see copyright notice in zlib.h 
 */

@@ -11,20 +11,22 @@

 struct internal_state      {int dummy;}; /* for buggy compilers */

-#ifndef __GO32__
+#ifndef STDC
 extern void exit OF((int));
 #endif

-char *zlib_version = ZLIB_VERSION;
+const char *zlib_version = ZLIB_VERSION;

-char *z_errmsg[] = {
-"stream end",          /* Z_STREAM_END    1 */
-"",                    /* Z_OK            0 */
-"file error",          /* Z_ERRNO        (-1) */
-"stream error",        /* Z_STREAM_ERROR (-2) */
-"data error",          /* Z_DATA_ERROR   (-3) */
-"insufficient memory", /* Z_MEM_ERROR    (-4) */
-"buffer error",        /* Z_BUF_ERROR    (-5) */
+const char *z_errmsg[10] = {
+"need dictionary",     /* Z_NEED_DICT       2  */
+"stream end",          /* Z_STREAM_END      1  */
+"",                    /* Z_OK              0  */
+"file error",          /* Z_ERRNO         (-1) */
+"stream error",        /* Z_STREAM_ERROR  (-2) */
+"data error",          /* Z_DATA_ERROR    (-3) */
+"insufficient memory", /* Z_MEM_ERROR     (-4) */
+"buffer error",        /* Z_BUF_ERROR     (-5) */
+"incompatible version",/* Z_VERSION_ERROR (-6) */
 ""};


@@ -59,9 +61,10 @@ void zmemzero(dest, len)
 }
 #endif

-#if defined( __TURBOC__) && !defined(__SMALL__) && !defined(__MEDIUM__)
-/* Small and medium model are for now limited to near allocation with
- * reduced MAX_WBITS and MAX_MEM_LEVEL
+#ifdef __TURBOC__
+#if (defined( __BORLANDC__) || !defined(SMALL_MEDIUM)) && !defined(__32BIT__)
+/* Small and medium model in Turbo C are for now limited to near allocation
+ * with reduced MAX_WBITS and MAX_MEM_LEVEL
 */
 #  define MY_ZCALLOC

@@ -94,7 +97,10 @@ voidpf zcalloc (voidpf opaque, unsigned items, unsigned size)
    voidpf buf = opaque; /* just to make some compilers happy */
    ulg bsize = (ulg)items*size;

-    if (bsize < 65536L) {
+    /* If we allocate less than 65520 bytes, we assume that farmalloc
+     * will return a usable pointer which doesn't have to be normalized.
+     */
+    if (bsize < 65520L) {
        buf = farmalloc(bsize);
        if (*(ush*)&buf != 0) return buf;
    } else {
@@ -131,9 +137,11 @@ void  zcfree (voidpf opaque, voidpf ptr)
    ptr = opaque; /* just to make some compilers happy */
    z_error("zcfree: ptr not found");
 }
+#endif
 #endif /* __TURBOC__ */

-#if defined(M_I86SM)||defined(M_I86MM)||defined(M_I86CM)||defined(M_I86LM)
+
+#if defined(M_I86) && !(defined(__WATCOMC__) && defined(__386__))
 /* Microsoft C */

 #  define MY_ZCALLOC
@@ -160,7 +168,7 @@ void  zcfree (voidpf opaque, voidpf ptr)

 #ifndef MY_ZCALLOC /* Any system without a special alloc function */

-#ifndef __GO32__
+#ifndef STDC
 extern voidp  calloc OF((uInt items, uInt size));
 extern void   free   OF((voidpf ptr));
 #endif
@@ -170,6 +178,7 @@ voidpf zcalloc (opaque, items, size)
    unsigned items;
    unsigned size;
 {
+    if (opaque) opaque = 0; /* to make compiler happy */
    return (voidpf)calloc(items, size);
 }

@@ -177,6 +186,7 @@ void  zcfree (opaque, ptr)
    voidpf opaque;
    voidpf ptr;
 {
+    if (opaque) opaque = 0; /* to make compiler happy */
    free(ptr);
 }

--- a/zutil.h
+++ b/zutil.h
@@ -1,5 +1,5 @@
 /* zutil.h -- internal interface and configuration of the compression library
- * Copyright (C) 1995 Jean-loup Gailly.
+ * Copyright (C) 1995-1996 Jean-loup Gailly.
 * For conditions of distribution and use, see copyright notice in zlib.h
 */

@@ -15,7 +15,7 @@

 #include "zlib.h"

-#if defined(MSDOS) || defined(VMS)
+#if defined(MSDOS) || defined(VMS) || defined(CRAY) || defined(WIN32)
 #   include <stddef.h>
 #   include <errno.h>
 #else
@@ -23,6 +23,7 @@
 #endif
 #ifdef STDC
 #  include <string.h>
+#  include <stdlib.h>
 #endif

 #ifndef local
@@ -36,15 +37,17 @@ typedef unsigned short ush;
 typedef ush FAR ushf;
 typedef unsigned long  ulg;

-extern char *z_errmsg[]; /* indexed by 1-zlib_error */
+extern const char *z_errmsg[10]; /* indexed by 2-zlib_error */
+/* (size given to avoid silly warnings with Visual C++) */

-#define ERR_RETURN(strm,err) return (strm->msg=z_errmsg[1-err], err)
+#define ERR_MSG(err) (char*)z_errmsg[Z_NEED_DICT-(err)]
+
+#define ERR_RETURN(strm,err) \
+  return (strm->msg = ERR_MSG(err), (err))
 /* To be used only when the state is known to be valid */

        /* common constants */

-#define DEFLATED   8
-
 #ifndef DEF_WBITS
 #  define DEF_WBITS MAX_WBITS
 #endif
@@ -66,6 +69,8 @@ extern char *z_errmsg[]; /* indexed by 1-zlib_error */
 #define MAX_MATCH  258
 /* The minimum and maximum match lengths */

+#define PRESET_DICT 0x20 /* preset dictionary flag in zlib header */
+
        /* target dependencies */

 #ifdef MSDOS
@@ -81,7 +86,7 @@ extern char *z_errmsg[]; /* indexed by 1-zlib_error */
 #  define OS_CODE  0x06
 #endif

-#ifdef WIN32 /* Windows NT */
+#ifdef WIN32 /* Window 95 & Windows NT */
 #  define OS_CODE  0x0b
 #endif

@@ -143,11 +148,13 @@ extern char *z_errmsg[]; /* indexed by 1-zlib_error */
 #  define HAVE_MEMCPY
 #endif
 #ifdef HAVE_MEMCPY
-#  if defined(M_I86SM) || defined(M_I86MM) /* MSC small or medium model */
+#  ifdef SMALL_MEDIUM /* MSDOS small or medium model */
 #    define zmemcpy _fmemcpy
+#    define zmemcmp _fmemcmp
 #    define zmemzero(dest, len) _fmemset(dest, 0, len)
 #  else
 #    define zmemcpy memcpy
+#    define zmemcmp memcmp
 #    define zmemzero(dest, len) memset(dest, 0, len)
 #  endif
 #else
@@ -177,7 +184,7 @@ extern char *z_errmsg[]; /* indexed by 1-zlib_error */
 #endif


-typedef uLong (*check_func) OF((uLong check, Bytef *buf, uInt len));
+typedef uLong (*check_func) OF((uLong check, const Bytef *buf, uInt len));

 extern void z_error    OF((char *m));