cmake_minimum_required(VERSION 2.4.4)
set(CMAKE_ALLOW_LOOSE_LOOP_CONSTRUCTS ON)

project(zlib C)

set(VERSION "1.2.7")

set(INSTALL_BIN_DIR "${CMAKE_INSTALL_PREFIX}/bin" CACHE PATH "Installation directory for executables")
set(INSTALL_LIB_DIR "${CMAKE_INSTALL_PREFIX}/lib" CACHE PATH "Installation directory for libraries")
set(INSTALL_INC_DIR "${CMAKE_INSTALL_PREFIX}/include" CACHE PATH "Installation directory for headers")
set(INSTALL_MAN_DIR "${CMAKE_INSTALL_PREFIX}/share/man" CACHE PATH "Installation directory for manual pages")
set(INSTALL_PKGCONFIG_DIR "${CMAKE_INSTALL_PREFIX}/share/pkgconfig" CACHE PATH "Installation directory for pkgconfig (.pc) files")

include(CheckTypeSize)
include(CheckFunctionExists)
include(CheckIncludeFile)
include(CheckCSourceCompiles)
enable_testing()

check_include_file(sys/types.h HAVE_SYS_TYPES_H)
check_include_file(stdint.h    HAVE_STDINT_H)
check_include_file(stddef.h    HAVE_STDDEF_H)

#
# Check to see if we have large file support
#
set(CMAKE_REQUIRED_DEFINITIONS -D_LARGEFILE64_SOURCE=1)
# We add these other definitions here because CheckTypeSize.cmake
# in CMake 2.4.x does not automatically do so and we want
# compatibility with CMake 2.4.x.
if(HAVE_SYS_TYPES_H)
    list(APPEND CMAKE_REQUIRED_DEFINITIONS -DHAVE_SYS_TYPES_H)
endif()
if(HAVE_STDINT_H)
    list(APPEND CMAKE_REQUIRED_DEFINITIONS -DHAVE_STDINT_H)
endif()
if(HAVE_STDDEF_H)
    list(APPEND CMAKE_REQUIRED_DEFINITIONS -DHAVE_STDDEF_H)
endif()
check_type_size(off64_t OFF64_T)
if(HAVE_OFF64_T)
   add_definitions(-D_LARGEFILE64_SOURCE=1)
endif()
set(CMAKE_REQUIRED_DEFINITIONS) # clear variable

#
# Check for fseeko
#
check_function_exists(fseeko HAVE_FSEEKO)
if(NOT HAVE_FSEEKO)
    add_definitions(-DNO_FSEEKO)
endif()

#
# Check for unistd.h
#
check_include_file(unistd.h Z_HAVE_UNISTD_H)

if(MSVC)
    set(CMAKE_DEBUG_POSTFIX "d")
    add_definitions(-D_CRT_SECURE_NO_DEPRECATE)
    add_definitions(-D_CRT_NONSTDC_NO_DEPRECATE)
    include_directories(${CMAKE_CURRENT_SOURCE_DIR})
endif()

if(NOT CMAKE_CURRENT_SOURCE_DIR STREQUAL CMAKE_CURRENT_BINARY_DIR)
    # If we're doing an out of source build and the user has a zconf.h
    # in their source tree...
    if(EXISTS ${CMAKE_CURRENT_SOURCE_DIR}/zconf.h)
        message(STATUS "Renaming")
        message(STATUS "    ${CMAKE_CURRENT_SOURCE_DIR}/zconf.h")
        message(STATUS "to 'zconf.h.included' because this file is included with zlib")
        message(STATUS "but CMake generates it automatically in the build directory.")
        file(RENAME ${CMAKE_CURRENT_SOURCE_DIR}/zconf.h ${CMAKE_CURRENT_SOURCE_DIR}/zconf.h.included)
  endif()
endif()

set(ZLIB_PC ${CMAKE_CURRENT_BINARY_DIR}/zlib.pc)
configure_file( ${CMAKE_CURRENT_SOURCE_DIR}/zlib.pc.cmakein
		${ZLIB_PC} @ONLY)
configure_file(	${CMAKE_CURRENT_SOURCE_DIR}/zconf.h.cmakein
		${CMAKE_CURRENT_BINARY_DIR}/zconf.h @ONLY)
include_directories(${CMAKE_CURRENT_BINARY_DIR} ${CMAKE_SOURCE_DIR})


#============================================================================
# zlib
#============================================================================

set(ZLIB_PUBLIC_HDRS
    ${CMAKE_CURRENT_BINARY_DIR}/zconf.h
    zlib.h
)
set(ZLIB_PRIVATE_HDRS
    crc32.h
    deflate.h
    gzguts.h
    inffast.h
    inffixed.h
    inflate.h
    inftrees.h
    trees.h
    zutil.h
)
set(ZLIB_SRCS
    adler32.c
    compress.c
    crc32.c
    deflate.c
    gzclose.c
    gzlib.c
    gzread.c
    gzwrite.c
    inflate.c
    infback.c
    inftrees.c
    inffast.c
    trees.c
    uncompr.c
    zutil.c
)

if(NOT MINGW)
    set(ZLIB_SRCS ${ZLIB_SRCS}
        win32/zlib1.rc # If present will override custom build rule below.
    )
endif()

# parse the full version number from zlib.h and include in ZLIB_FULL_VERSION
file(READ ${CMAKE_CURRENT_SOURCE_DIR}/zlib.h _zlib_h_contents)
string(REGEX REPLACE ".*#define[ \t]+ZLIB_VERSION[ \t]+\"([-0-9A-Za-z.]+)\".*"
    "\\1" ZLIB_FULL_VERSION ${_zlib_h_contents})

if(MINGW)
    # This gets us DLL resource information when compiling on MinGW.
    if(NOT CMAKE_RC_COMPILER)
        SET(CMAKE_RC_COMPILER windres.exe)
    endif()

    add_custom_command(OUTPUT ${CMAKE_CURRENT_BINARY_DIR}/zlib1rc.obj
                       COMMAND ${CMAKE_RC_COMPILER}
                            -D GCC_WINDRES
                            -I ${CMAKE_CURRENT_SOURCE_DIR}
                            -I ${CMAKE_CURRENT_BINARY_DIR}
                            -o ${CMAKE_CURRENT_BINARY_DIR}/zlib1rc.obj
                            -i ${CMAKE_CURRENT_SOURCE_DIR}/win32/zlib1.rc)
    set(ZLIB_SRCS ${ZLIB_SRCS} ${CMAKE_CURRENT_BINARY_DIR}/zlib1rc.obj)
endif(MINGW)

add_library(zlib SHARED ${ZLIB_SRCS} ${ZLIB_PUBLIC_HDRS} ${ZLIB_PRIVATE_HDRS})
add_library(zlibstatic STATIC ${ZLIB_SRCS} ${ZLIB_PUBLIC_HDRS} ${ZLIB_PRIVATE_HDRS})
set_target_properties(zlib PROPERTIES DEFINE_SYMBOL ZLIB_DLL)
set_target_properties(zlib PROPERTIES SOVERSION 1)

if(NOT CYGWIN)
    # This property causes shared libraries on Linux to have the full version
    # encoded into their final filename.  We disable this on Cygwin because
    # it causes cygz-${ZLIB_FULL_VERSION}.dll to be created when cygz.dll
    # seems to be the default.
    #
    # This has no effect with MSVC, on that platform the version info for
    # the DLL comes from the resource file win32/zlib1.rc
    set_target_properties(zlib PROPERTIES VERSION ${ZLIB_FULL_VERSION})
endif()

if(UNIX)
    # On unix-like platforms the library is almost always called libz
   set_target_properties(zlib zlibstatic PROPERTIES OUTPUT_NAME z)
   set_target_properties(zlib PROPERTIES LINK_FLAGS "-Wl,--version-script,${CMAKE_CURRENT_SOURCE_DIR}/zlib.map")
elseif(BUILD_SHARED_LIBS AND WIN32)
    # Creates zlib1.dll when building shared library version
    set_target_properties(zlib PROPERTIES SUFFIX "1.dll")
endif()

if(NOT SKIP_INSTALL_LIBRARIES AND NOT SKIP_INSTALL_ALL )
    install(TARGETS zlib zlibstatic
        RUNTIME DESTINATION "${INSTALL_BIN_DIR}"
        ARCHIVE DESTINATION "${INSTALL_LIB_DIR}"
        LIBRARY DESTINATION "${INSTALL_LIB_DIR}" )
endif()
if(NOT SKIP_INSTALL_HEADERS AND NOT SKIP_INSTALL_ALL )
    install(FILES ${ZLIB_PUBLIC_HDRS} DESTINATION "${INSTALL_INC_DIR}")
endif()
if(NOT SKIP_INSTALL_FILES AND NOT SKIP_INSTALL_ALL )
    install(FILES zlib.3 DESTINATION "${INSTALL_MAN_DIR}/man3")
endif()
if(NOT SKIP_INSTALL_FILES AND NOT SKIP_INSTALL_ALL )
    install(FILES ${ZLIB_PC} DESTINATION "${INSTALL_PKGCONFIG_DIR}")
endif()

#============================================================================
# Example binaries
#============================================================================

add_executable(example test/example.c)
target_link_libraries(example zlib)
add_test(example example)

add_executable(minigzip test/minigzip.c)
target_link_libraries(minigzip zlib)

if(HAVE_OFF64_T)
    add_executable(example64 test/example.c)
    target_link_libraries(example64 zlib)
    set_target_properties(example64 PROPERTIES COMPILE_FLAGS "-D_FILE_OFFSET_BITS=64")
    add_test(example64 example64)

    add_executable(minigzip64 test/minigzip.c)
    target_link_libraries(minigzip64 zlib)
    set_target_properties(minigzip64 PROPERTIES COMPILE_FLAGS "-D_FILE_OFFSET_BITS=64")
endif()

                ChangeLog file for zlib

Changes in 1.2.7 (2 May 2012)
- Replace use of memmove() with a simple copy for portability
- Test for existence of strerror
- Restore gzgetc_ for backward compatibility with 1.2.6
- Fix build with non-GNU make on Solaris
- Require gcc 4.0 or later on Mac OS X to use the hidden attribute
- Include unistd.h for Watcom C
- Use __WATCOMC__ instead of __WATCOM__
- Do not use the visibility attribute if NO_VIZ defined
- Improve the detection of no hidden visibility attribute
- Avoid using __int64 for gcc or solo compilation
- Cast to char * in gzprintf to avoid warnings [Zinser]
- Fix make_vms.com for VAX [Zinser]
- Don't use library or built-in byte swaps
- Simplify test and use of gcc hidden attribute
- Fix bug in gzclose_w() when gzwrite() fails to allocate memory
- Add "x" (O_EXCL) and "e" (O_CLOEXEC) modes support to gzopen()
- Fix bug in test/minigzip.c for configure --solo
- Fix contrib/vstudio project link errors [Mohanathas]
- Add ability to choose the builder in make_vms.com [Schweda]
- Add DESTDIR support to mingw32 win32/Makefile.gcc
- Fix comments in win32/Makefile.gcc for proper usage
- Allow overriding the default install locations for cmake
- Generate and install the pkg-config file with cmake
- Build both a static and a shared version of zlib with cmake
- Include version symbols for cmake builds
- If using cmake with MSVC, add the source directory to the includes
- Remove unneeded EXTRA_CFLAGS from win32/Makefile.gcc [Truta]
- Move obsolete emx makefile to old [Truta]
- Allow the use of -Wundef when compiling or using zlib
- Avoid the use of the -u option with mktemp
- Improve inflate() documentation on the use of Z_FINISH
- Recognize clang as gcc
- Add gzopen_w() in Windows for wide character path names
- Rename zconf.h in CMakeLists.txt to move it out of the way
- Add source directory in CMakeLists.txt for building examples
- Look in build directory for zlib.pc in CMakeLists.txt
- Remove gzflags from zlibvc.def in vc9 and vc10
- Fix contrib/minizip compilation in the MinGW environment
- Update ./configure for Solaris, support --64 [Mooney]
- Remove -R. from Solaris shared build (possible security issue)
- Avoid race condition for parallel make (-j) running example
- Fix type mismatch between get_crc_table() and crc_table
- Fix parsing of version with "-" in CMakeLists.txt [Snider, Ziegler]
- Fix the path to zlib.map in CMakeLists.txt
- Force the native libtool in Mac OS X to avoid GNU libtool [Beebe]
- Add instructions to win32/Makefile.gcc for shared install [Torri]

Changes in 1.2.6.1 (12 Feb 2012)
- Avoid the use of the Objective-C reserved name "id"
- Include io.h in gzguts.h for Microsoft compilers
- Fix problem with ./configure --prefix and gzgetc macro
- Include gz_header definition when compiling zlib solo
- Put gzflags() functionality back in zutil.c
- Avoid library header include in crc32.c for Z_SOLO
- Use name in GCC_CLASSIC as C compiler for coverage testing, if set
- Minor cleanup in contrib/minizip/zip.c [Vollant]
- Update make_vms.com [Zinser]
- Remove unnecessary gzgetc_ function
- Use optimized byte swap operations for Microsoft and GNU [Snyder]
- Fix minor typo in zlib.h comments [Rzesniowiecki]

Changes in 1.2.6 (29 Jan 2012)
- Update the Pascal interface in contrib/pascal
- Fix function numbers for gzgetc_ in zlibvc.def files
- Fix configure.ac for contrib/minizip [Schiffer]
- Fix large-entry detection in minizip on 64-bit systems [Schiffer]
- Have ./configure use the compiler return code for error indication
- Fix CMakeLists.txt for cross compilation [McClure]
- Fix contrib/minizip/zip.c for 64-bit architectures [Dalsnes]
- Fix compilation of contrib/minizip on FreeBSD [Marquez]
- Correct suggested usages in win32/Makefile.msc [Shachar, Horvath]
- Include io.h for Turbo C / Borland C on all platforms [Truta]
- Make version explicit in contrib/minizip/configure.ac [Bosmans]
- Avoid warning for no encryption in contrib/minizip/zip.c [Vollant]
- Minor cleanup up contrib/minizip/unzip.c [Vollant]
- Fix bug when compiling minizip with C++ [Vollant]
- Protect for long name and extra fields in contrib/minizip [Vollant]
- Avoid some warnings in contrib/minizip [Vollant]
- Add -I../.. -L../.. to CFLAGS for minizip and miniunzip
- Add missing libs to minizip linker command
- Add support for VPATH builds in contrib/minizip
- Add an --enable-demos option to contrib/minizip/configure
- Add the generation of configure.log by ./configure
- Exit when required parameters not provided to win32/Makefile.gcc
- Have gzputc return the character written instead of the argument
- Use the -m option on ldconfig for BSD systems [Tobias]
- Correct in zlib.map when deflateResetKeep was added

Changes in 1.2.5.3 (15 Jan 2012)
- Restore gzgetc function for binary compatibility
- Do not use _lseeki64 under Borland C++ [Truta]
- Update win32/Makefile.msc to build test/*.c [Truta]
- Remove old/visualc6 given CMakefile and other alternatives
- Update AS400 build files and documentation [Monnerat]
- Update win32/Makefile.gcc to build test/*.c [Truta]
- Permit stronger flushes after Z_BLOCK flushes
- Avoid extraneous empty blocks when doing empty flushes
- Permit Z_NULL arguments to deflatePending
- Allow deflatePrime() to insert bits in the middle of a stream
- Remove second empty static block for Z_PARTIAL_FLUSH
- Write out all of the available bits when using Z_BLOCK
- Insert the first two strings in the hash table after a flush

Changes in 1.2.5.2 (17 Dec 2011)
- fix ld error: unable to find version dependency 'ZLIB_1.2.5'
- use relative symlinks for shared libs
- Avoid searching past window for Z_RLE strategy
- Assure that high-water mark initialization is always applied in deflate
- Add assertions to fill_window() in deflate.c to match comments
- Update python link in README
- Correct spelling error in gzread.c
- Fix bug in gzgets() for a concatenated empty gzip stream
- Correct error in comment for gz_make()
- Change gzread() and related to ignore junk after gzip streams
- Allow gzread() and related to continue after gzclearerr()
- Allow gzrewind() and gzseek() after a premature end-of-file
- Simplify gzseek() now that raw after gzip is ignored
- Change gzgetc() to a macro for speed (~40% speedup in testing)
- Fix gzclose() to return the actual error last encountered
- Always add large file support for windows
- Include zconf.h for windows large file support
- Include zconf.h.cmakein for windows large file support
- Update zconf.h.cmakein on make distclean
- Merge vestigial vsnprintf determination from zutil.h to gzguts.h
- Clarify how gzopen() appends in zlib.h comments
- Correct documentation of gzdirect() since junk at end now ignored
- Add a transparent write mode to gzopen() when 'T' is in the mode
- Update python link in zlib man page
- Get inffixed.h and MAKEFIXED result to match
- Add a ./config --solo option to make zlib subset with no libary use
- Add undocumented inflateResetKeep() function for CAB file decoding
- Add --cover option to ./configure for gcc coverage testing
- Add #define ZLIB_CONST option to use const in the z_stream interface
- Add comment to gzdopen() in zlib.h to use dup() when using fileno()
- Note behavior of uncompress() to provide as much data as it can
- Add files in contrib/minizip to aid in building libminizip
- Split off AR options in Makefile.in and configure
- Change ON macro to Z_ARG to avoid application conflicts
- Facilitate compilation with Borland C++ for pragmas and vsnprintf
- Include io.h for Turbo C / Borland C++
- Move example.c and minigzip.c to test/
- Simplify incomplete code table filling in inflate_table()
- Remove code from inflate.c and infback.c that is impossible to execute
- Test the inflate code with full coverage
- Allow deflateSetDictionary, inflateSetDictionary at any time (in raw)
- Add deflateResetKeep and fix inflateResetKeep to retain dictionary
- Fix gzwrite.c to accommodate reduced memory zlib compilation
- Have inflate() with Z_FINISH avoid the allocation of a window
- Do not set strm->adler when doing raw inflate
- Fix gzeof() to behave just like feof() when read is not past end of file
- Fix bug in gzread.c when end-of-file is reached
- Avoid use of Z_BUF_ERROR in gz* functions except for premature EOF
- Document gzread() capability to read concurrently written files
- Remove hard-coding of resource compiler in CMakeLists.txt [Blammo]

Changes in 1.2.5.1 (10 Sep 2011)
- Update FAQ entry on shared builds (#13)
- Avoid symbolic argument to chmod in Makefile.in
- Fix bug and add consts in contrib/puff [Oberhumer]
- Update contrib/puff/zeros.raw test file to have all block types
- Add full coverage test for puff in contrib/puff/Makefile
- Fix static-only-build install in Makefile.in
- Fix bug in unzGetCurrentFileInfo() in contrib/minizip [Kuno]
- Add libz.a dependency to shared in Makefile.in for parallel builds
- Spell out "number" (instead of "nb") in zlib.h for total_in, total_out
- Replace $(...) with `...` in configure for non-bash sh [Bowler]
- Add darwin* to Darwin* and solaris* to SunOS\ 5* in configure [Groffen]
- Add solaris* to Linux* in configure to allow gcc use [Groffen]
- Add *bsd* to Linux* case in configure [Bar-Lev]
- Add inffast.obj to dependencies in win32/Makefile.msc
- Correct spelling error in deflate.h [Kohler]
- Change libzdll.a again to libz.dll.a (!) in win32/Makefile.gcc
- Add test to configure for GNU C looking for gcc in output of $cc -v
- Add zlib.pc generation to win32/Makefile.gcc [Weigelt]
- Fix bug in zlib.h for _FILE_OFFSET_BITS set and _LARGEFILE64_SOURCE not
- Add comment in zlib.h that adler32_combine with len2 < 0 makes no sense
- Make NO_DIVIDE option in adler32.c much faster (thanks to John Reiser)
- Make stronger test in zconf.h to include unistd.h for LFS
- Apply Darwin patches for 64-bit file offsets to contrib/minizip [Slack]
- Fix zlib.h LFS support when Z_PREFIX used
- Add updated as400 support (removed from old) [Monnerat]
- Avoid deflate sensitivity to volatile input data
- Avoid division in adler32_combine for NO_DIVIDE
- Clarify the use of Z_FINISH with deflateBound() amount of space
- Set binary for output file in puff.c
- Use u4 type for crc_table to avoid conversion warnings
- Apply casts in zlib.h to avoid conversion warnings
- Add OF to prototypes for adler32_combine_ and crc32_combine_ [Miller]
- Improve inflateSync() documentation to note indeterminancy
- Add deflatePending() function to return the amount of pending output
- Correct the spelling of "specification" in FAQ [Randers-Pehrson]
- Add a check in configure for stdarg.h, use for gzprintf()
- Check that pointers fit in ints when gzprint() compiled old style
- Add dummy name before $(SHAREDLIBV) in Makefile [Bar-Lev, Bowler]
- Delete line in configure that adds -L. libz.a to LDFLAGS [Weigelt]
- Add debug records in assmebler code [Londer]
- Update RFC references to use http://tools.ietf.org/html/... [Li]
- Add --archs option, use of libtool to configure for Mac OS X [Borstel]

Changes in 1.2.5 (19 Apr 2010)
- Disable visibility attribute in win32/Makefile.gcc [Bar-Lev]
- Default to libdir as sharedlibdir in configure [Nieder]
- Update copyright dates on modified source files
- Update trees.c to be able to generate modified trees.h
- Exit configure for MinGW, suggesting win32/Makefile.gcc
- Check for NULL path in gz_open [Homurlu]

Changes in 1.2.4.5 (18 Apr 2010)
- Set sharedlibdir in configure [Torok]
- Set LDFLAGS in Makefile.in [Bar-Lev]
- Avoid mkdir objs race condition in Makefile.in [Bowler]
- Add ZLIB_INTERNAL in front of internal inter-module functions and arrays
- Define ZLIB_INTERNAL to hide internal functions and arrays for GNU C
- Don't use hidden attribute when it is a warning generator (e.g. Solaris)

Changes in 1.2.4.4 (18 Apr 2010)
- Fix CROSS_PREFIX executable testing, CHOST extract, mingw* [Torok]
- Undefine _LARGEFILE64_SOURCE in zconf.h if it is zero, but not if empty
- Try to use bash or ksh regardless of functionality of /bin/sh
- Fix configure incompatibility with NetBSD sh
- Remove attempt to run under bash or ksh since have better NetBSD fix
- Fix win32/Makefile.gcc for MinGW [Bar-Lev]
- Add diagnostic messages when using CROSS_PREFIX in configure
- Added --sharedlibdir option to configure [Weigelt]
- Use hidden visibility attribute when available [Frysinger]

Changes in 1.2.4.3 (10 Apr 2010)
- Only use CROSS_PREFIX in configure for ar and ranlib if they exist
- Use CROSS_PREFIX for nm [Bar-Lev]
- Assume _LARGEFILE64_SOURCE defined is equivalent to true
- Avoid use of undefined symbols in #if with && and ||
- Make *64 prototypes in gzguts.h consistent with functions
- Add -shared load option for MinGW in configure [Bowler]
- Move z_off64_t to public interface, use instead of off64_t
- Remove ! from shell test in configure (not portable to Solaris)
- Change +0 macro tests to -0 for possibly increased portability

Changes in 1.2.4.2 (9 Apr 2010)
- Add consistent carriage returns to readme.txt's in masmx86 and masmx64
- Really provide prototypes for *64 functions when building without LFS
- Only define unlink() in minigzip.c if unistd.h not included
- Update README to point to contrib/vstudio project files
- Move projects/vc6 to old/ and remove projects/
- Include stdlib.h in minigzip.c for setmode() definition under WinCE
- Clean up assembler builds in win32/Makefile.msc [Rowe]
- Include sys/types.h for Microsoft for off_t definition
- Fix memory leak on error in gz_open()
- Symbolize nm as $NM in configure [Weigelt]
- Use TEST_LDSHARED instead of LDSHARED to link test programs [Weigelt]
- Add +0 to _FILE_OFFSET_BITS and _LFS64_LARGEFILE in case not defined
- Fix bug in gzeof() to take into account unused input data
- Avoid initialization of structures with variables in puff.c
- Updated win32/README-WIN32.txt [Rowe]

Changes in 1.2.4.1 (28 Mar 2010)
- Remove the use of [a-z] constructs for sed in configure [gentoo 310225]
- Remove $(SHAREDLIB) from LIBS in Makefile.in [Creech]
- Restore "for debugging" comment on sprintf() in gzlib.c
- Remove fdopen for MVS from gzguts.h
- Put new README-WIN32.txt in win32 [Rowe]
- Add check for shell to configure and invoke another shell if needed
- Fix big fat stinking bug in gzseek() on uncompressed files
- Remove vestigial F_OPEN64 define in zutil.h
- Set and check the value of _LARGEFILE_SOURCE and _LARGEFILE64_SOURCE
- Avoid errors on non-LFS systems when applications define LFS macros
- Set EXE to ".exe" in configure for MINGW [Kahle]
- Match crc32() in crc32.c exactly to the prototype in zlib.h [Sherrill]
- Add prefix for cross-compilation in win32/makefile.gcc [Bar-Lev]
- Add DLL install in win32/makefile.gcc [Bar-Lev]
- Allow Linux* or linux* from uname in configure [Bar-Lev]
- Allow ldconfig to be redefined in configure and Makefile.in [Bar-Lev]
- Add cross-compilation prefixes to configure [Bar-Lev]
- Match type exactly in gz_load() invocation in gzread.c
- Match type exactly of zcalloc() in zutil.c to zlib.h alloc_func
- Provide prototypes for *64 functions when building zlib without LFS
- Don't use -lc when linking shared library on MinGW
- Remove errno.h check in configure and vestigial errno code in zutil.h

Changes in 1.2.4 (14 Mar 2010)
- Fix VER3 extraction in configure for no fourth subversion
- Update zlib.3, add docs to Makefile.in to make .pdf out of it
- Add zlib.3.pdf to distribution
- Don't set error code in gzerror() if passed pointer is NULL
- Apply destination directory fixes to CMakeLists.txt [Lowman]
- Move #cmakedefine's to a new zconf.in.cmakein
- Restore zconf.h for builds that don't use configure or cmake
- Add distclean to dummy Makefile for convenience
- Update and improve INDEX, README, and FAQ
- Update CMakeLists.txt for the return of zconf.h [Lowman]
- Update contrib/vstudio/vc9 and vc10 [Vollant]
- Change libz.dll.a back to libzdll.a in win32/Makefile.gcc
- Apply license and readme changes to contrib/asm686 [Raiter]
- Check file name lengths and add -c option in minigzip.c [Li]
- Update contrib/amd64 and contrib/masmx86/ [Vollant]
- Avoid use of "eof" parameter in trees.c to not shadow library variable
- Update make_vms.com for removal of zlibdefs.h [Zinser]
- Update assembler code and vstudio projects in contrib [Vollant]
- Remove outdated assembler code contrib/masm686 and contrib/asm586
- Remove old vc7 and vc8 from contrib/vstudio
- Update win32/Makefile.msc, add ZLIB_VER_SUBREVISION [Rowe]
- Fix memory leaks in gzclose_r() and gzclose_w(), file leak in gz_open()
- Add contrib/gcc_gvmat64 for longest_match and inflate_fast [Vollant]
- Remove *64 functions from win32/zlib.def (they're not 64-bit yet)
- Fix bug in void-returning vsprintf() case in gzwrite.c
- Fix name change from inflate.h in contrib/inflate86/inffas86.c
- Check if temporary file exists before removing in make_vms.com [Zinser]
- Fix make install and uninstall for --static option
- Fix usage of _MSC_VER in gzguts.h and zutil.h [Truta]
- Update readme.txt in contrib/masmx64 and masmx86 to assemble

Changes in 1.2.3.9 (21 Feb 2010)
- Expunge gzio.c
- Move as400 build information to old
- Fix updates in contrib/minizip and contrib/vstudio
- Add const to vsnprintf test in configure to avoid warnings [Weigelt]
- Delete zconf.h (made by configure) [Weigelt]
- Change zconf.in.h to zconf.h.in per convention [Weigelt]
- Check for NULL buf in gzgets()
- Return empty string for gzgets() with len == 1 (like fgets())
- Fix description of gzgets() in zlib.h for end-of-file, NULL return
- Update minizip to 1.1 [Vollant]
- Avoid MSVC loss of data warnings in gzread.c, gzwrite.c
- Note in zlib.h that gzerror() should be used to distinguish from EOF
- Remove use of snprintf() from gzlib.c
- Fix bug in gzseek()
- Update contrib/vstudio, adding vc9 and vc10 [Kuno, Vollant]
- Fix zconf.h generation in CMakeLists.txt [Lowman]
- Improve comments in zconf.h where modified by configure

Changes in 1.2.3.8 (13 Feb 2010)
- Clean up text files (tabs, trailing whitespace, etc.) [Oberhumer]
- Use z_off64_t in gz_zero() and gz_skip() to match state->skip
- Avoid comparison problem when sizeof(int) == sizeof(z_off64_t)
- Revert to Makefile.in from 1.2.3.6 (live with the clutter)
- Fix missing error return in gzflush(), add zlib.h note
- Add *64 functions to zlib.map [Levin]
- Fix signed/unsigned comparison in gz_comp()
- Use SFLAGS when testing shared linking in configure
- Add --64 option to ./configure to use -m64 with gcc
- Fix ./configure --help to correctly name options
- Have make fail if a test fails [Levin]
- Avoid buffer overrun in contrib/masmx64/gvmat64.asm [Simpson]
- Remove assembler object files from contrib

Changes in 1.2.3.7 (24 Jan 2010)
- Always gzopen() with O_LARGEFILE if available
- Fix gzdirect() to work immediately after gzopen() or gzdopen()
- Make gzdirect() more precise when the state changes while reading
- Improve zlib.h documentation in many places
- Catch memory allocation failure in gz_open()
- Complete close operation if seek forward in gzclose_w() fails
- Return Z_ERRNO from gzclose_r() if close() fails
- Return Z_STREAM_ERROR instead of EOF for gzclose() being passed NULL
- Return zero for gzwrite() errors to match zlib.h description
- Return -1 on gzputs() error to match zlib.h description
- Add zconf.in.h to allow recovery from configure modification [Weigelt]
- Fix static library permissions in Makefile.in [Weigelt]
- Avoid warnings in configure tests that hide functionality [Weigelt]
- Add *BSD and DragonFly to Linux case in configure [gentoo 123571]
- Change libzdll.a to libz.dll.a in win32/Makefile.gcc [gentoo 288212]
- Avoid access of uninitialized data for first inflateReset2 call [Gomes]
- Keep object files in subdirectories to reduce the clutter somewhat
- Remove default Makefile and zlibdefs.h, add dummy Makefile
- Add new external functions to Z_PREFIX, remove duplicates, z_z_ -> z_
- Remove zlibdefs.h completely -- modify zconf.h instead

Changes in 1.2.3.6 (17 Jan 2010)
- Avoid void * arithmetic in gzread.c and gzwrite.c
- Make compilers happier with const char * for gz_error message
- Avoid unused parameter warning in inflate.c
- Avoid signed-unsigned comparison warning in inflate.c
- Indent #pragma's for traditional C
- Fix usage of strwinerror() in glib.c, change to gz_strwinerror()
- Correct email address in configure for system options
- Update make_vms.com and add make_vms.com to contrib/minizip [Zinser]
- Update zlib.map [Brown]
- Fix Makefile.in for Solaris 10 make of example64 and minizip64 [Torok]
- Apply various fixes to CMakeLists.txt [Lowman]
- Add checks on len in gzread() and gzwrite()
- Add error message for no more room for gzungetc()
- Remove zlib version check in gzwrite()
- Defer compression of gzprintf() result until need to
- Use snprintf() in gzdopen() if available
- Remove USE_MMAP configuration determination (only used by minigzip)
- Remove examples/pigz.c (available separately)
- Update examples/gun.c to 1.6

Changes in 1.2.3.5 (8 Jan 2010)
- Add space after #if in zutil.h for some compilers
- Fix relatively harmless bug in deflate_fast() [Exarevsky]
- Fix same problem in deflate_slow()
- Add $(SHAREDLIBV) to LIBS in Makefile.in [Brown]
- Add deflate_rle() for faster Z_RLE strategy run-length encoding
- Add deflate_huff() for faster Z_HUFFMAN_ONLY encoding
- Change name of "write" variable in inffast.c to avoid library collisions
- Fix premature EOF from gzread() in gzio.c [Brown]
- Use zlib header window size if windowBits is 0 in inflateInit2()
- Remove compressBound() call in deflate.c to avoid linking compress.o
- Replace use of errno in gz* with functions, support WinCE [Alves]
- Provide alternative to perror() in minigzip.c for WinCE [Alves]
- Don't use _vsnprintf on later versions of MSVC [Lowman]
- Add CMake build script and input file [Lowman]
- Update contrib/minizip to 1.1 [Svensson, Vollant]
- Moved nintendods directory from contrib to .
- Replace gzio.c with a new set of routines with the same functionality
- Add gzbuffer(), gzoffset(), gzclose_r(), gzclose_w() as part of above
- Update contrib/minizip to 1.1b
- Change gzeof() to return 0 on error instead of -1 to agree with zlib.h

Changes in 1.2.3.4 (21 Dec 2009)
- Use old school .SUFFIXES in Makefile.in for FreeBSD compatibility
- Update comments in configure and Makefile.in for default --shared
- Fix test -z's in configure [Marquess]
- Build examplesh and minigzipsh when not testing
- Change NULL's to Z_NULL's in deflate.c and in comments in zlib.h
- Import LDFLAGS from the environment in configure
- Fix configure to populate SFLAGS with discovered CFLAGS options
- Adapt make_vms.com to the new Makefile.in [Zinser]
- Add zlib2ansi script for C++ compilation [Marquess]
- Add _FILE_OFFSET_BITS=64 test to make test (when applicable)
- Add AMD64 assembler code for longest match to contrib [Teterin]
- Include options from $SFLAGS when doing $LDSHARED
- Simplify 64-bit file support by introducing z_off64_t type
- Make shared object files in objs directory to work around old Sun cc
- Use only three-part version number for Darwin shared compiles
- Add rc option to ar in Makefile.in for when ./configure not run
- Add -WI,-rpath,. to LDFLAGS for OSF 1 V4*
- Set LD_LIBRARYN32_PATH for SGI IRIX shared compile
- Protect against _FILE_OFFSET_BITS being defined when compiling zlib
- Rename Makefile.in targets allstatic to static and allshared to shared
- Fix static and shared Makefile.in targets to be independent
- Correct error return bug in gz_open() by setting state [Brown]
- Put spaces before ;;'s in configure for better sh compatibility
- Add pigz.c (parallel implementation of gzip) to examples/
- Correct constant in crc32.c to UL [Leventhal]
- Reject negative lengths in crc32_combine()
- Add inflateReset2() function to work like inflateEnd()/inflateInit2()
- Include sys/types.h for _LARGEFILE64_SOURCE [Brown]
- Correct typo in doc/algorithm.txt [Janik]
- Fix bug in adler32_combine() [Zhu]
- Catch missing-end-of-block-code error in all inflates and in puff
    Assures that random input to inflate eventually results in an error
- Added enough.c (calculation of ENOUGH for inftrees.h) to examples/
- Update ENOUGH and its usage to reflect discovered bounds
- Fix gzerror() error report on empty input file [Brown]
- Add ush casts in trees.c to avoid pedantic runtime errors
- Fix typo in zlib.h uncompress() description [Reiss]
- Correct inflate() comments with regard to automatic header detection
- Remove deprecation comment on Z_PARTIAL_FLUSH (it stays)
- Put new version of gzlog (2.0) in examples with interruption recovery
- Add puff compile option to permit invalid distance-too-far streams
- Add puff TEST command options, ability to read piped input
- Prototype the *64 functions in zlib.h when _FILE_OFFSET_BITS == 64, but
  _LARGEFILE64_SOURCE not defined
- Fix Z_FULL_FLUSH to truly erase the past by resetting s->strstart
- Fix deflateSetDictionary() to use all 32K for output consistency
- Remove extraneous #define MIN_LOOKAHEAD in deflate.c (in deflate.h)
- Clear bytes after deflate lookahead to avoid use of uninitialized data
- Change a limit in inftrees.c to be more transparent to Coverity Prevent
- Update win32/zlib.def with exported symbols from zlib.h
- Correct spelling errors in zlib.h [Willem, Sobrado]
- Allow Z_BLOCK for deflate() to force a new block
- Allow negative bits in inflatePrime() to delete existing bit buffer
- Add Z_TREES flush option to inflate() to return at end of trees
- Add inflateMark() to return current state information for random access
- Add Makefile for NintendoDS to contrib [Costa]
- Add -w in configure compile tests to avoid spurious warnings [Beucler]
- Fix typos in zlib.h comments for deflateSetDictionary()
- Fix EOF detection in transparent gzread() [Maier]

Changes in 1.2.3.3 (2 October 2006)
- Make --shared the default for configure, add a --static option
- Add compile option to permit invalid distance-too-far streams
- Add inflateUndermine() function which is required to enable above
- Remove use of "this" variable name for C++ compatibility [Marquess]
- Add testing of shared library in make test, if shared library built
- Use ftello() and fseeko() if available instead of ftell() and fseek()
- Provide two versions of all functions that use the z_off_t type for
  binary compatibility -- a normal version and a 64-bit offset version,
  per the Large File Support Extension when _LARGEFILE64_SOURCE is
  defined; use the 64-bit versions by default when _FILE_OFFSET_BITS
  is defined to be 64
- Add a --uname= option to configure to perhaps help with cross-compiling

Changes in 1.2.3.2 (3 September 2006)
- Turn off silly Borland warnings [Hay]
- Use off64_t and define _LARGEFILE64_SOURCE when present
- Fix missing dependency on inffixed.h in Makefile.in
- Rig configure --shared to build both shared and static [Teredesai, Truta]
- Remove zconf.in.h and instead create a new zlibdefs.h file
- Fix contrib/minizip/unzip.c non-encrypted after encrypted [Vollant]
- Add treebuild.xml (see http://treebuild.metux.de/) [Weigelt]

Changes in 1.2.3.1 (16 August 2006)
- Add watcom directory with OpenWatcom make files [Daniel]
- Remove #undef of FAR in zconf.in.h for MVS [Fedtke]
- Update make_vms.com [Zinser]
- Use -fPIC for shared build in configure [Teredesai, Nicholson]
- Use only major version number for libz.so on IRIX and OSF1 [Reinholdtsen]
- Use fdopen() (not _fdopen()) for Interix in zutil.h [BŠck]
- Add some FAQ entries about the contrib directory
- Update the MVS question in the FAQ
- Avoid extraneous reads after EOF in gzio.c [Brown]
- Correct spelling of "successfully" in gzio.c [Randers-Pehrson]
- Add comments to zlib.h about gzerror() usage [Brown]
- Set extra flags in gzip header in gzopen() like deflate() does
- Make configure options more compatible with double-dash conventions
  [Weigelt]
- Clean up compilation under Solaris SunStudio cc [Rowe, Reinholdtsen]
- Fix uninstall target in Makefile.in [Truta]
- Add pkgconfig support [Weigelt]
- Use $(DESTDIR) macro in Makefile.in [Reinholdtsen, Weigelt]
- Replace set_data_type() with a more accurate detect_data_type() in
  trees.c, according to the txtvsbin.txt document [Truta]
- Swap the order of #include <stdio.h> and #include "zlib.h" in
  gzio.c, example.c and minigzip.c [Truta]
- Shut up annoying VS2005 warnings about standard C deprecation [Rowe,
  Truta] (where?)
- Fix target "clean" from win32/Makefile.bor [Truta]
- Create .pdb and .manifest files in win32/makefile.msc [Ziegler, Rowe]
- Update zlib www home address in win32/DLL_FAQ.txt [Truta]
- Update contrib/masmx86/inffas32.asm for VS2005 [Vollant, Van Wassenhove]
- Enable browse info in the "Debug" and "ASM Debug" configurations in
  the Visual C++ 6 project, and set (non-ASM) "Debug" as default [Truta]
- Add pkgconfig support [Weigelt]
- Add ZLIB_VER_MAJOR, ZLIB_VER_MINOR and ZLIB_VER_REVISION in zlib.h,
  for use in win32/zlib1.rc [Polushin, Rowe, Truta]
- Add a document that explains the new text detection scheme to
  doc/txtvsbin.txt [Truta]
- Add rfc1950.txt, rfc1951.txt and rfc1952.txt to doc/ [Truta]
- Move algorithm.txt into doc/ [Truta]
- Synchronize FAQ with website
- Fix compressBound(), was low for some pathological cases [Fearnley]
- Take into account wrapper variations in deflateBound()
- Set examples/zpipe.c input and output to binary mode for Windows
- Update examples/zlib_how.html with new zpipe.c (also web site)
- Fix some warnings in examples/gzlog.c and examples/zran.c (it seems
  that gcc became pickier in 4.0)
- Add zlib.map for Linux: "All symbols from zlib-1.1.4 remain
  un-versioned, the patch adds versioning only for symbols introduced in
  zlib-1.2.0 or later.  It also declares as local those symbols which are
  not designed to be exported." [Levin]
- Update Z_PREFIX list in zconf.in.h, add --zprefix option to configure
- Do not initialize global static by default in trees.c, add a response
  NO_INIT_GLOBAL_POINTERS to initialize them if needed [Marquess]
- Don't use strerror() in gzio.c under WinCE [Yakimov]
- Don't use errno.h in zutil.h under WinCE [Yakimov]
- Move arguments for AR to its usage to allow replacing ar [Marot]
- Add HAVE_VISIBILITY_PRAGMA in zconf.in.h for Mozilla [Randers-Pehrson]
- Improve inflateInit() and inflateInit2() documentation
- Fix structure size comment in inflate.h
- Change configure help option from --h* to --help [Santos]

Changes in 1.2.3 (18 July 2005)
- Apply security vulnerability fixes to contrib/infback9 as well
- Clean up some text files (carriage returns, trailing space)
- Update testzlib, vstudio, masmx64, and masmx86 in contrib [Vollant]

Changes in 1.2.2.4 (11 July 2005)
- Add inflatePrime() function for starting inflation at bit boundary
- Avoid some Visual C warnings in deflate.c
- Avoid more silly Visual C warnings in inflate.c and inftrees.c for 64-bit
  compile
- Fix some spelling errors in comments [Betts]
- Correct inflateInit2() error return documentation in zlib.h
- Add zran.c example of compressed data random access to examples
  directory, shows use of inflatePrime()
- Fix cast for assignments to strm->state in inflate.c and infback.c
- Fix zlibCompileFlags() in zutil.c to use 1L for long shifts [Oberhumer]
- Move declarations of gf2 functions to right place in crc32.c [Oberhumer]
- Add cast in trees.c t avoid a warning [Oberhumer]
- Avoid some warnings in fitblk.c, gun.c, gzjoin.c in examples [Oberhumer]
- Update make_vms.com [Zinser]
- Initialize state->write in inflateReset() since copied in inflate_fast()
- Be more strict on incomplete code sets in inflate_table() and increase
  ENOUGH and MAXD -- this repairs a possible security vulnerability for
  invalid inflate input.  Thanks to Tavis Ormandy and Markus Oberhumer for
  discovering the vulnerability and providing test cases.
- Add ia64 support to configure for HP-UX [Smith]
- Add error return to gzread() for format or i/o error [Levin]
- Use malloc.h for OS/2 [Necasek]

Changes in 1.2.2.3 (27 May 2005)
- Replace 1U constants in inflate.c and inftrees.c for 64-bit compile
- Typecast fread() return values in gzio.c [Vollant]
- Remove trailing space in minigzip.c outmode (VC++ can't deal with it)
- Fix crc check bug in gzread() after gzungetc() [Heiner]
- Add the deflateTune() function to adjust internal compression parameters
- Add a fast gzip decompressor, gun.c, to examples (use of inflateBack)
- Remove an incorrect assertion in examples/zpipe.c
- Add C++ wrapper in infback9.h [Donais]
- Fix bug in inflateCopy() when decoding fixed codes
- Note in zlib.h how much deflateSetDictionary() actually uses
- Remove USE_DICT_HEAD in deflate.c (would mess up inflate if used)
- Add _WIN32_WCE to define WIN32 in zconf.in.h [Spencer]
- Don't include stderr.h or errno.h for _WIN32_WCE in zutil.h [Spencer]
- Add gzdirect() function to indicate transparent reads
- Update contrib/minizip [Vollant]
- Fix compilation of deflate.c when both ASMV and FASTEST [Oberhumer]
- Add casts in crc32.c to avoid warnings [Oberhumer]
- Add contrib/masmx64 [Vollant]
- Update contrib/asm586, asm686, masmx86, testzlib, vstudio [Vollant]

Changes in 1.2.2.2 (30 December 2004)
- Replace structure assignments in deflate.c and inflate.c with zmemcpy to
  avoid implicit memcpy calls (portability for no-library compilation)
- Increase sprintf() buffer size in gzdopen() to allow for large numbers
- Add INFLATE_STRICT to check distances against zlib header
- Improve WinCE errno handling and comments [Chang]
- Remove comment about no gzip header processing in FAQ
- Add Z_FIXED strategy option to deflateInit2() to force fixed trees
- Add updated make_vms.com [Coghlan], update README
- Create a new "examples" directory, move gzappend.c there, add zpipe.c,
  fitblk.c, gzlog.[ch], gzjoin.c, and zlib_how.html.
- Add FAQ entry and comments in deflate.c on uninitialized memory access
- Add Solaris 9 make options in configure [Gilbert]
- Allow strerror() usage in gzio.c for STDC
- Fix DecompressBuf in contrib/delphi/ZLib.pas [ManChesTer]
- Update contrib/masmx86/inffas32.asm and gvmat32.asm [Vollant]
- Use z_off_t for adler32_combine() and crc32_combine() lengths
- Make adler32() much faster for small len
- Use OS_CODE in deflate() default gzip header

Changes in 1.2.2.1 (31 October 2004)
- Allow inflateSetDictionary() call for raw inflate
- Fix inflate header crc check bug for file names and comments
- Add deflateSetHeader() and gz_header structure for custom gzip headers
- Add inflateGetheader() to retrieve gzip headers
- Add crc32_combine() and adler32_combine() functions
- Add alloc_func, free_func, in_func, out_func to Z_PREFIX list
- Use zstreamp consistently in zlib.h (inflate_back functions)
- Remove GUNZIP condition from definition of inflate_mode in inflate.h
  and in contrib/inflate86/inffast.S [Truta, Anderson]
- Add support for AMD64 in contrib/inflate86/inffas86.c [Anderson]
- Update projects/README.projects and projects/visualc6 [Truta]
- Update win32/DLL_FAQ.txt [Truta]
- Avoid warning under NO_GZCOMPRESS in gzio.c; fix typo [Truta]
- Deprecate Z_ASCII; use Z_TEXT instead [Truta]
- Use a new algorithm for setting strm->data_type in trees.c [Truta]
- Do not define an exit() prototype in zutil.c unless DEBUG defined
- Remove prototype of exit() from zutil.c, example.c, minigzip.c [Truta]
- Add comment in zlib.h for Z_NO_FLUSH parameter to deflate()
- Fix Darwin build version identification [Peterson]

Changes in 1.2.2 (3 October 2004)
- Update zlib.h comments on gzip in-memory processing
- Set adler to 1 in inflateReset() to support Java test suite [Walles]
- Add contrib/dotzlib [Ravn]
- Update win32/DLL_FAQ.txt [Truta]
- Update contrib/minizip [Vollant]
- Move contrib/visual-basic.txt to old/ [Truta]
- Fix assembler builds in projects/visualc6/ [Truta]

Changes in 1.2.1.2 (9 September 2004)
- Update INDEX file
- Fix trees.c to update strm->data_type (no one ever noticed!)
- Fix bug in error case in inflate.c, infback.c, and infback9.c [Brown]
- Add "volatile" to crc table flag declaration (for DYNAMIC_CRC_TABLE)
- Add limited multitasking protection to DYNAMIC_CRC_TABLE
- Add NO_vsnprintf for VMS in zutil.h [Mozilla]
- Don't declare strerror() under VMS [Mozilla]
- Add comment to DYNAMIC_CRC_TABLE to use get_crc_table() to initialize
- Update contrib/ada [Anisimkov]
- Update contrib/minizip [Vollant]
- Fix configure to not hardcode directories for Darwin [Peterson]
- Fix gzio.c to not return error on empty files [Brown]
- Fix indentation; update version in contrib/delphi/ZLib.pas and
  contrib/pascal/zlibpas.pas [Truta]
- Update mkasm.bat in contrib/masmx86 [Truta]
- Update contrib/untgz [Truta]
- Add projects/README.projects [Truta]
- Add project for MS Visual C++ 6.0 in projects/visualc6 [Cadieux, Truta]
- Update win32/DLL_FAQ.txt [Truta]
- Update list of Z_PREFIX symbols in zconf.h [Randers-Pehrson, Truta]
- Remove an unnecessary assignment to curr in inftrees.c [Truta]
- Add OS/2 to exe builds in configure [Poltorak]
- Remove err dummy parameter in zlib.h [Kientzle]

Changes in 1.2.1.1 (9 January 2004)
- Update email address in README
- Several FAQ updates
- Fix a big fat bug in inftrees.c that prevented decoding valid
  dynamic blocks with only literals and no distance codes --
  Thanks to "Hot Emu" for the bug report and sample file
- Add a note to puff.c on no distance codes case.

Changes in 1.2.1 (17 November 2003)
- Remove a tab in contrib/gzappend/gzappend.c
- Update some interfaces in contrib for new zlib functions
- Update zlib version number in some contrib entries
- Add Windows CE definition for ptrdiff_t in zutil.h [Mai, Truta]
- Support shared libraries on Hurd and KFreeBSD [Brown]
- Fix error in NO_DIVIDE option of adler32.c

Changes in 1.2.0.8 (4 November 2003)
- Update version in contrib/delphi/ZLib.pas and contrib/pascal/zlibpas.pas
- Add experimental NO_DIVIDE #define in adler32.c
    - Possibly faster on some processors (let me know if it is)
- Correct Z_BLOCK to not return on first inflate call if no wrap
- Fix strm->data_type on inflate() return to correctly indicate EOB
- Add deflatePrime() function for appending in the middle of a byte
- Add contrib/gzappend for an example of appending to a stream
- Update win32/DLL_FAQ.txt [Truta]
- Delete Turbo C comment in README [Truta]
- Improve some indentation in zconf.h [Truta]
- Fix infinite loop on bad input in configure script [Church]
- Fix gzeof() for concatenated gzip files [Johnson]
- Add example to contrib/visual-basic.txt [Michael B.]
- Add -p to mkdir's in Makefile.in [vda]
- Fix configure to properly detect presence or lack of printf functions
- Add AS400 support [Monnerat]
- Add a little Cygwin support [Wilson]

Changes in 1.2.0.7 (21 September 2003)
- Correct some debug formats in contrib/infback9
- Cast a type in a debug statement in trees.c
- Change search and replace delimiter in configure from % to # [Beebe]
- Update contrib/untgz to 0.2 with various fixes [Truta]
- Add build support for Amiga [Nikl]
- Remove some directories in old that have been updated to 1.2
- Add dylib building for Mac OS X in configure and Makefile.in
- Remove old distribution stuff from Makefile
- Update README to point to DLL_FAQ.txt, and add comment on Mac OS X
- Update links in README

Changes in 1.2.0.6 (13 September 2003)
- Minor FAQ updates
- Update contrib/minizip to 1.00 [Vollant]
- Remove test of gz functions in example.c when GZ_COMPRESS defined [Truta]
- Update POSTINC comment for 68060 [Nikl]
- Add contrib/infback9 with deflate64 decoding (unsupported)
- For MVS define NO_vsnprintf and undefine FAR [van Burik]
- Add pragma for fdopen on MVS [van Burik]

Changes in 1.2.0.5 (8 September 2003)
- Add OF to inflateBackEnd() declaration in zlib.h
- Remember start when using gzdopen in the middle of a file
- Use internal off_t counters in gz* functions to properly handle seeks
- Perform more rigorous check for distance-too-far in inffast.c
- Add Z_BLOCK flush option to return from inflate at block boundary
- Set strm->data_type on return from inflate
    - Indicate bits unused, if at block boundary, and if in last block
- Replace size_t with ptrdiff_t in crc32.c, and check for correct size
- Add condition so old NO_DEFLATE define still works for compatibility
- FAQ update regarding the Windows DLL [Truta]
- INDEX update: add qnx entry, remove aix entry [Truta]
- Install zlib.3 into mandir [Wilson]
- Move contrib/zlib_dll_FAQ.txt to win32/DLL_FAQ.txt; update [Truta]
- Adapt the zlib interface to the new DLL convention guidelines [Truta]
- Introduce ZLIB_WINAPI macro to allow the export of functions using
  the WINAPI calling convention, for Visual Basic [Vollant, Truta]
- Update msdos and win32 scripts and makefiles [Truta]
- Export symbols by name, not by ordinal, in win32/zlib.def [Truta]
- Add contrib/ada [Anisimkov]
- Move asm files from contrib/vstudio/vc70_32 to contrib/asm386 [Truta]
- Rename contrib/asm386 to contrib/masmx86 [Truta, Vollant]
- Add contrib/masm686 [Truta]
- Fix offsets in contrib/inflate86 and contrib/masmx86/inffas32.asm
  [Truta, Vollant]
- Update contrib/delphi; rename to contrib/pascal; add example [Truta]
- Remove contrib/delphi2; add a new contrib/delphi [Truta]
- Avoid inclusion of the nonstandard <memory.h> in contrib/iostream,
  and fix some method prototypes [Truta]
- Fix the ZCR_SEED2 constant to avoid warnings in contrib/minizip
  [Truta]
- Avoid the use of backslash (\) in contrib/minizip [Vollant]
- Fix file time handling in contrib/untgz; update makefiles [Truta]
- Update contrib/vstudio/vc70_32 to comply with the new DLL guidelines
  [Vollant]
- Remove contrib/vstudio/vc15_16 [Vollant]
- Rename contrib/vstudio/vc70_32 to contrib/vstudio/vc7 [Truta]
- Update README.contrib [Truta]
- Invert the assignment order of match_head and s->prev[...] in
  INSERT_STRING [Truta]
- Compare TOO_FAR with 32767 instead of 32768, to avoid 16-bit warnings
  [Truta]
- Compare function pointers with 0, not with NULL or Z_NULL [Truta]
- Fix prototype of syncsearch in inflate.c [Truta]
- Introduce ASMINF macro to be enabled when using an ASM implementation
  of inflate_fast [Truta]
- Change NO_DEFLATE to NO_GZCOMPRESS [Truta]
- Modify test_gzio in example.c to take a single file name as a
  parameter [Truta]
- Exit the example.c program if gzopen fails [Truta]
- Add type casts around strlen in example.c [Truta]
- Remove casting to sizeof in minigzip.c; give a proper type
  to the variable compared with SUFFIX_LEN [Truta]
- Update definitions of STDC and STDC99 in zconf.h [Truta]
- Synchronize zconf.h with the new Windows DLL interface [Truta]
- Use SYS16BIT instead of __32BIT__ to distinguish between
  16- and 32-bit platforms [Truta]
- Use far memory allocators in small 16-bit memory models for
  Turbo C [Truta]
- Add info about the use of ASMV, ASMINF and ZLIB_WINAPI in
  zlibCompileFlags [Truta]
- Cygwin has vsnprintf [Wilson]
- In Windows16, OS_CODE is 0, as in MSDOS [Truta]
- In Cygwin, OS_CODE is 3 (Unix), not 11 (Windows32) [Wilson]

Changes in 1.2.0.4 (10 August 2003)
- Minor FAQ updates
- Be more strict when checking inflateInit2's windowBits parameter
- Change NO_GUNZIP compile option to NO_GZIP to cover deflate as well
- Add gzip wrapper option to deflateInit2 using windowBits
- Add updated QNX rule in configure and qnx directory [Bonnefoy]
- Make inflate distance-too-far checks more rigorous
- Clean up FAR usage in inflate
- Add casting to sizeof() in gzio.c and minigzip.c

Changes in 1.2.0.3 (19 July 2003)
- Fix silly error in gzungetc() implementation [Vollant]
- Update contrib/minizip and contrib/vstudio [Vollant]
- Fix printf format in example.c
- Correct cdecl support in zconf.in.h [Anisimkov]
- Minor FAQ updates

Changes in 1.2.0.2 (13 July 2003)
- Add ZLIB_VERNUM in zlib.h for numerical preprocessor comparisons
- Attempt to avoid warnings in crc32.c for pointer-int conversion
- Add AIX to configure, remove aix directory [Bakker]
- Add some casts to minigzip.c
- Improve checking after insecure sprintf() or vsprintf() calls
- Remove #elif's from crc32.c
- Change leave label to inf_leave in inflate.c and infback.c to avoid
  library conflicts
- Remove inflate gzip decoding by default--only enable gzip decoding by
  special request for stricter backward compatibility
- Add zlibCompileFlags() function to return compilation information
- More typecasting in deflate.c to avoid warnings
- Remove leading underscore from _Capital #defines [Truta]
- Fix configure to link shared library when testing
- Add some Windows CE target adjustments [Mai]
- Remove #define ZLIB_DLL in zconf.h [Vollant]
- Add zlib.3 [Rodgers]
- Update RFC URL in deflate.c and algorithm.txt [Mai]
- Add zlib_dll_FAQ.txt to contrib [Truta]
- Add UL to some constants [Truta]
- Update minizip and vstudio [Vollant]
- Remove vestigial NEED_DUMMY_RETURN from zconf.in.h
- Expand use of NO_DUMMY_DECL to avoid all dummy structures
- Added iostream3 to contrib [Schwardt]
- Replace rewind() with fseek() for WinCE [Truta]
- Improve setting of zlib format compression level flags
    - Report 0 for huffman and rle strategies and for level == 0 or 1
    - Report 2 only for level == 6
- Only deal with 64K limit when necessary at compile time [Truta]
- Allow TOO_FAR check to be turned off at compile time [Truta]
- Add gzclearerr() function [Souza]
- Add gzungetc() function

Changes in 1.2.0.1 (17 March 2003)
- Add Z_RLE strategy for run-length encoding [Truta]
    - When Z_RLE requested, restrict matches to distance one
    - Update zlib.h, minigzip.c, gzopen(), gzdopen() for Z_RLE
- Correct FASTEST compilation to allow level == 0
- Clean up what gets compiled for FASTEST
- Incorporate changes to zconf.in.h [Vollant]
    - Refine detection of Turbo C need for dummy returns
    - Refine ZLIB_DLL compilation
    - Include additional header file on VMS for off_t typedef
- Try to use _vsnprintf where it supplants vsprintf [Vollant]
- Add some casts in inffast.c
- Enchance comments in zlib.h on what happens if gzprintf() tries to
  write more than 4095 bytes before compression
- Remove unused state from inflateBackEnd()
- Remove exit(0) from minigzip.c, example.c
- Get rid of all those darn tabs
- Add "check" target to Makefile.in that does the same thing as "test"
- Add "mostlyclean" and "maintainer-clean" targets to Makefile.in
- Update contrib/inflate86 [Anderson]
- Update contrib/testzlib, contrib/vstudio, contrib/minizip [Vollant]
- Add msdos and win32 directories with makefiles [Truta]
- More additions and improvements to the FAQ

Changes in 1.2.0 (9 March 2003)
- New and improved inflate code
    - About 20% faster
    - Does not allocate 32K window unless and until needed
    - Automatically detects and decompresses gzip streams
    - Raw inflate no longer needs an extra dummy byte at end
    - Added inflateBack functions using a callback interface--even faster
      than inflate, useful for file utilities (gzip, zip)
    - Added inflateCopy() function to record state for random access on
      externally generated deflate streams (e.g. in gzip files)
    - More readable code (I hope)
- New and improved crc32()
    - About 50% faster, thanks to suggestions from Rodney Brown
- Add deflateBound() and compressBound() functions
- Fix memory leak in deflateInit2()
- Permit setting dictionary for raw deflate (for parallel deflate)
- Fix const declaration for gzwrite()
- Check for some malloc() failures in gzio.c
- Fix bug in gzopen() on single-byte file 0x1f
- Fix bug in gzread() on concatenated file with 0x1f at end of buffer
  and next buffer doesn't start with 0x8b
- Fix uncompress() to return Z_DATA_ERROR on truncated input
- Free memory at end of example.c
- Remove MAX #define in trees.c (conflicted with some libraries)
- Fix static const's in deflate.c, gzio.c, and zutil.[ch]
- Declare malloc() and free() in gzio.c if STDC not defined
- Use malloc() instead of calloc() in zutil.c if int big enough
- Define STDC for AIX
- Add aix/ with approach for compiling shared library on AIX
- Add HP-UX support for shared libraries in configure
- Add OpenUNIX support for shared libraries in configure
- Use $cc instead of gcc to build shared library
- Make prefix directory if needed when installing
- Correct Macintosh avoidance of typedef Byte in zconf.h
- Correct Turbo C memory allocation when under Linux
- Use libz.a instead of -lz in Makefile (assure use of compiled library)
- Update configure to check for snprintf or vsnprintf functions and their
  return value, warn during make if using an insecure function
- Fix configure problem with compile-time knowledge of HAVE_UNISTD_H that
  is lost when library is used--resolution is to build new zconf.h
- Documentation improvements (in zlib.h):
    - Document raw deflate and inflate
    - Update RFCs URL
    - Point out that zlib and gzip formats are different
    - Note that Z_BUF_ERROR is not fatal
    - Document string limit for gzprintf() and possible buffer overflow
    - Note requirement on avail_out when flushing
    - Note permitted values of flush parameter of inflate()
- Add some FAQs (and even answers) to the FAQ
- Add contrib/inflate86/ for x86 faster inflate
- Add contrib/blast/ for PKWare Data Compression Library decompression
- Add contrib/puff/ simple inflate for deflate format description

Changes in 1.1.4 (11 March 2002)
- ZFREE was repeated on same allocation on some error conditions.
  This creates a security problem described in
  http://www.zlib.org/advisory-2002-03-11.txt
- Returned incorrect error (Z_MEM_ERROR) on some invalid data
- Avoid accesses before window for invalid distances with inflate window
  less than 32K.
- force windowBits > 8 to avoid a bug in the encoder for a window size
  of 256 bytes. (A complete fix will be available in 1.1.5).

Changes in 1.1.3 (9 July 1998)
- fix "an inflate input buffer bug that shows up on rare but persistent
  occasions" (Mark)
- fix gzread and gztell for concatenated .gz files (Didier Le Botlan)
- fix gzseek(..., SEEK_SET) in write mode
- fix crc check after a gzeek (Frank Faubert)
- fix miniunzip when the last entry in a zip file is itself a zip file
  (J Lillge)
- add contrib/asm586 and contrib/asm686 (Brian Raiter)
  See http://www.muppetlabs.com/~breadbox/software/assembly.html
- add support for Delphi 3 in contrib/delphi (Bob Dellaca)
- add support for C++Builder 3 and Delphi 3 in contrib/delphi2 (Davide Moretti)
- do not exit prematurely in untgz if 0 at start of block (Magnus Holmgren)
- use macro EXTERN instead of extern to support DLL for BeOS (Sander Stoks)
- added a FAQ file

- Support gzdopen on Mac with Metrowerks (Jason Linhart)
- Do not redefine Byte on Mac (Brad Pettit & Jason Linhart)
- define SEEK_END too if SEEK_SET is not defined (Albert Chin-A-Young)
- avoid some warnings with Borland C (Tom Tanner)
- fix a problem in contrib/minizip/zip.c for 16-bit MSDOS (Gilles Vollant)
- emulate utime() for WIN32 in contrib/untgz  (Gilles Vollant)
- allow several arguments to configure (Tim Mooney, Frodo Looijaard)
- use libdir and includedir in Makefile.in (Tim Mooney)
- support shared libraries on OSF1 V4 (Tim Mooney)
- remove so_locations in "make clean"  (Tim Mooney)
- fix maketree.c compilation error (Glenn, Mark)
- Python interface to zlib now in Python 1.5 (Jeremy Hylton)
- new Makefile.riscos (Rich Walker)
- initialize static descriptors in trees.c for embedded targets (Nick Smith)
- use "foo-gz" in example.c for RISCOS and VMS (Nick Smith)
- add the OS/2 files in Makefile.in too (Andrew Zabolotny)
- fix fdopen and halloc macros for Microsoft C 6.0 (Tom Lane)
- fix maketree.c to allow clean compilation of inffixed.h (Mark)
- fix parameter check in deflateCopy (Gunther Nikl)
- cleanup trees.c, use compressed_len only in debug mode (Christian Spieler)
- Many portability patches by Christian Spieler:
  . zutil.c, zutil.h: added "const" for zmem*
  . Make_vms.com: fixed some typos
  . Make_vms.com: msdos/Makefile.*: removed zutil.h from some dependency lists
  . msdos/Makefile.msc: remove "default rtl link library" info from obj files
  . msdos/Makefile.*: use model-dependent name for the built zlib library
  . msdos/Makefile.emx, nt/Makefile.emx, nt/Makefile.gcc:
     new makefiles, for emx (DOS/OS2), emx&rsxnt and mingw32 (Windows 9x / NT)
- use define instead of typedef for Bytef also for MSC small/medium (Tom Lane)
- replace __far with _far for better portability (Christian Spieler, Tom Lane)
- fix test for errno.h in configure (Tim Newsham)

Changes in 1.1.2 (19 March 98)
- added contrib/minzip, mini zip and unzip based on zlib (Gilles Vollant)
  See http://www.winimage.com/zLibDll/unzip.html
- preinitialize the inflate tables for fixed codes, to make the code
  completely thread safe (Mark)
- some simplifications and slight speed-up to the inflate code (Mark)
- fix gzeof on non-compressed files (Allan Schrum)
- add -std1 option in configure for OSF1 to fix gzprintf (Martin Mokrejs)
- use default value of 4K for Z_BUFSIZE for 16-bit MSDOS (Tim Wegner + Glenn)
- added os2/Makefile.def and os2/zlib.def (Andrew Zabolotny)
- add shared lib support for UNIX_SV4.2MP (MATSUURA Takanori)
- do not wrap extern "C" around system includes (Tom Lane)
- mention zlib binding for TCL in README (Andreas Kupries)
- added amiga/Makefile.pup for Amiga powerUP SAS/C PPC (Andreas Kleinert)
- allow "make install prefix=..." even after configure (Glenn Randers-Pehrson)
- allow "configure --prefix $HOME" (Tim Mooney)
- remove warnings in example.c and gzio.c (Glenn Randers-Pehrson)
- move Makefile.sas to amiga/Makefile.sas

Changes in 1.1.1 (27 Feb 98)
- fix macros _tr_tally_* in deflate.h for debug mode  (Glenn Randers-Pehrson)
- remove block truncation heuristic which had very marginal effect for zlib
  (smaller lit_bufsize than in gzip 1.2.4) and degraded a little the
  compression ratio on some files. This also allows inlining _tr_tally for
  matches in deflate_slow.
- added msdos/Makefile.w32 for WIN32 Microsoft Visual C++ (Bob Frazier)

Changes in 1.1.0 (24 Feb 98)
- do not return STREAM_END prematurely in inflate (John Bowler)
- revert to the zlib 1.0.8 inflate to avoid the gcc 2.8.0 bug (Jeremy Buhler)
- compile with -DFASTEST to get compression code optimized for speed only
- in minigzip, try mmap'ing the input file first (Miguel Albrecht)
- increase size of I/O buffers in minigzip.c and gzio.c (not a big gain
  on Sun but significant on HP)

- add a pointer to experimental unzip library in README (Gilles Vollant)
- initialize variable gcc in configure (Chris Herborth)

Changes in 1.0.9 (17 Feb 1998)
- added gzputs and gzgets functions
- do not clear eof flag in gzseek (Mark Diekhans)
- fix gzseek for files in transparent mode (Mark Diekhans)
- do not assume that vsprintf returns the number of bytes written (Jens Krinke)
- replace EXPORT with ZEXPORT to avoid conflict with other programs
- added compress2 in zconf.h, zlib.def, zlib.dnt
- new asm code from Gilles Vollant in contrib/asm386
- simplify the inflate code (Mark):
 . Replace ZALLOC's in huft_build() with single ZALLOC in inflate_blocks_new()
 . ZALLOC the length list in inflate_trees_fixed() instead of using stack
 . ZALLOC the value area for huft_build() instead of using stack
 . Simplify Z_FINISH check in inflate()

- Avoid gcc 2.8.0 comparison bug a little differently than zlib 1.0.8
- in inftrees.c, avoid cc -O bug on HP (Farshid Elahi)
- in zconf.h move the ZLIB_DLL stuff earlier to avoid problems with
  the declaration of FAR (Gilles VOllant)
- install libz.so* with mode 755 (executable) instead of 644 (Marc Lehmann)
- read_buf buf parameter of type Bytef* instead of charf*
- zmemcpy parameters are of type Bytef*, not charf* (Joseph Strout)
- do not redeclare unlink in minigzip.c for WIN32 (John Bowler)
- fix check for presence of directories in "make install" (Ian Willis)

Changes in 1.0.8 (27 Jan 1998)
- fixed offsets in contrib/asm386/gvmat32.asm (Gilles Vollant)
- fix gzgetc and gzputc for big endian systems (Markus Oberhumer)
- added compress2() to allow setting the compression level
- include sys/types.h to get off_t on some systems (Marc Lehmann & QingLong)
- use constant arrays for the static trees in trees.c instead of computing
  them at run time (thanks to Ken Raeburn for this suggestion). To create
  trees.h, compile with GEN_TREES_H and run "make test".
- check return code of example in "make test" and display result
- pass minigzip command line options to file_compress
- simplifying code of inflateSync to avoid gcc 2.8 bug

- support CC="gcc -Wall" in configure -s (QingLong)
- avoid a flush caused by ftell in gzopen for write mode (Ken Raeburn)
- fix test for shared library support to avoid compiler warnings
- zlib.lib -> zlib.dll in msdos/zlib.rc (Gilles Vollant)
- check for TARGET_OS_MAC in addition to MACOS (Brad Pettit)
- do not use fdopen for Metrowerks on Mac (Brad Pettit))
- add checks for gzputc and gzputc in example.c
- avoid warnings in gzio.c and deflate.c (Andreas Kleinert)
- use const for the CRC table (Ken Raeburn)
- fixed "make uninstall" for shared libraries
- use Tracev instead of Trace in infblock.c
- in example.c use correct compressed length for test_sync
- suppress +vnocompatwarnings in configure for HPUX (not always supported)

Changes in 1.0.7 (20 Jan 1998)
- fix gzseek which was broken in write mode
- return error for gzseek to negative absolute position
- fix configure for Linux (Chun-Chung Chen)
- increase stack space for MSC (Tim Wegner)
- get_crc_table and inflateSyncPoint are EXPORTed (Gilles Vollant)
- define EXPORTVA for gzprintf (Gilles Vollant)
- added man page zlib.3 (Rick Rodgers)
- for contrib/untgz, fix makedir() and improve Makefile

- check gzseek in write mode in example.c
- allocate extra buffer for seeks only if gzseek is actually called
- avoid signed/unsigned comparisons (Tim Wegner, Gilles Vollant)
- add inflateSyncPoint in zconf.h
- fix list of exported functions in nt/zlib.dnt and mdsos/zlib.def

Changes in 1.0.6 (19 Jan 1998)
- add functions gzprintf, gzputc, gzgetc, gztell, gzeof, gzseek, gzrewind and
  gzsetparams (thanks to Roland Giersig and Kevin Ruland for some of this code)
- Fix a deflate bug occurring only with compression level 0 (thanks to
  Andy Buckler for finding this one).
- In minigzip, pass transparently also the first byte for .Z files.
- return Z_BUF_ERROR instead of Z_OK if output buffer full in uncompress()
- check Z_FINISH in inflate (thanks to Marc Schluper)
- Implement deflateCopy (thanks to Adam Costello)
- make static libraries by default in configure, add --shared option.
- move MSDOS or Windows specific files to directory msdos
- suppress the notion of partial flush to simplify the interface
  (but the symbol Z_PARTIAL_FLUSH is kept for compatibility with 1.0.4)
- suppress history buffer provided by application to simplify the interface
  (this feature was not implemented anyway in 1.0.4)
- next_in and avail_in must be initialized before calling inflateInit or
  inflateInit2
- add EXPORT in all exported functions (for Windows DLL)
- added Makefile.nt (thanks to Stephen Williams)
- added the unsupported "contrib" directory:
   contrib/asm386/ by Gilles Vollant <info@winimage.com>
        386 asm code replacing longest_match().
   contrib/iostream/ by Kevin Ruland <kevin@rodin.wustl.edu>
        A C++ I/O streams interface to the zlib gz* functions
   contrib/iostream2/  by Tyge Løvset <Tyge.Lovset@cmr.no>
        Another C++ I/O streams interface
   contrib/untgz/  by "Pedro A. Aranda Guti\irrez" <paag@tid.es>
        A very simple tar.gz file extractor using zlib
   contrib/visual-basic.txt by Carlos Rios <c_rios@sonda.cl>
        How to use compress(), uncompress() and the gz* functions from VB.
- pass params -f (filtered data), -h (huffman only), -1 to -9 (compression
  level) in minigzip (thanks to Tom Lane)

- use const for rommable constants in deflate
- added test for gzseek and gztell in example.c
- add undocumented function inflateSyncPoint() (hack for Paul Mackerras)
- add undocumented function zError to convert error code to string
  (for Tim Smithers)
- Allow compilation of gzio with -DNO_DEFLATE to avoid the compression code.
- Use default memcpy for Symantec MSDOS compiler.
- Add EXPORT keyword for check_func (needed for Windows DLL)
- add current directory to LD_LIBRARY_PATH for "make test"
- create also a link for libz.so.1
- added support for FUJITSU UXP/DS (thanks to Toshiaki Nomura)
- use $(SHAREDLIB) instead of libz.so in Makefile.in (for HPUX)
- added -soname for Linux in configure (Chun-Chung Chen,
- assign numbers to the exported functions in zlib.def (for Windows DLL)
- add advice in zlib.h for best usage of deflateSetDictionary
- work around compiler bug on Atari (cast Z_NULL in call of s->checkfn)
- allow compilation with ANSI keywords only enabled for TurboC in large model
- avoid "versionString"[0] (Borland bug)
- add NEED_DUMMY_RETURN for Borland
- use variable z_verbose for tracing in debug mode (L. Peter Deutsch).
- allow compilation with CC
- defined STDC for OS/2 (David Charlap)
- limit external names to 8 chars for MVS (Thomas Lund)
- in minigzip.c, use static buffers only for 16-bit systems
- fix suffix check for "minigzip -d foo.gz"
- do not return an error for the 2nd of two consecutive gzflush() (Felix Lee)
- use _fdopen instead of fdopen for MSC >= 6.0 (Thomas Fanslau)
- added makelcc.bat for lcc-win32 (Tom St Denis)
- in Makefile.dj2, use copy and del instead of install and rm (Frank Donahoe)
- Avoid expanded $Id$. Use "rcs -kb" or "cvs admin -kb" to avoid Id expansion.
- check for unistd.h in configure (for off_t)
- remove useless check parameter in inflate_blocks_free
- avoid useless assignment of s->check to itself in inflate_blocks_new
- do not flush twice in gzclose (thanks to Ken Raeburn)
- rename FOPEN as F_OPEN to avoid clash with /usr/include/sys/file.h
- use NO_ERRNO_H instead of enumeration of operating systems with errno.h
- work around buggy fclose on pipes for HP/UX
- support zlib DLL with BORLAND C++ 5.0 (thanks to Glenn Randers-Pehrson)
- fix configure if CC is already equal to gcc

Changes in 1.0.5 (3 Jan 98)
- Fix inflate to terminate gracefully when fed corrupted or invalid data
- Use const for rommable constants in inflate
- Eliminate memory leaks on error conditions in inflate
- Removed some vestigial code in inflate
- Update web address in README

Changes in 1.0.4 (24 Jul 96)
- In very rare conditions, deflate(s, Z_FINISH) could fail to produce an EOF
  bit, so the decompressor could decompress all the correct data but went
  on to attempt decompressing extra garbage data. This affected minigzip too.
- zlibVersion and gzerror return const char* (needed for DLL)
- port to RISCOS (no fdopen, no multiple dots, no unlink, no fileno)
- use z_error only for DEBUG (avoid problem with DLLs)

Changes in 1.0.3 (2 Jul 96)
- use z_streamp instead of z_stream *, which is now a far pointer in MSDOS
  small and medium models; this makes the library incompatible with previous
  versions for these models. (No effect in large model or on other systems.)
- return OK instead of BUF_ERROR if previous deflate call returned with
  avail_out as zero but there is nothing to do
- added memcmp for non STDC compilers
- define NO_DUMMY_DECL for more Mac compilers (.h files merged incorrectly)
- define __32BIT__ if __386__ or i386 is defined (pb. with Watcom and SCO)
- better check for 16-bit mode MSC (avoids problem with Symantec)

Changes in 1.0.2 (23 May 96)
- added Windows DLL support
- added a function zlibVersion (for the DLL support)
- fixed declarations using Bytef in infutil.c (pb with MSDOS medium model)
- Bytef is define's instead of typedef'd only for Borland C
- avoid reading uninitialized memory in example.c
- mention in README that the zlib format is now RFC1950
- updated Makefile.dj2
- added algorithm.doc

Changes in 1.0.1 (20 May 96) [1.0 skipped to avoid confusion]
- fix array overlay in deflate.c which sometimes caused bad compressed data
- fix inflate bug with empty stored block
- fix MSDOS medium model which was broken in 0.99
- fix deflateParams() which could generated bad compressed data.
- Bytef is define'd instead of typedef'ed (work around Borland bug)
- added an INDEX file
- new makefiles for DJGPP (Makefile.dj2), 32-bit Borland (Makefile.b32),
  Watcom (Makefile.wat), Amiga SAS/C (Makefile.sas)
- speed up adler32 for modern machines without auto-increment
- added -ansi for IRIX in configure
- static_init_done in trees.c is an int
- define unlink as delete for VMS
- fix configure for QNX
- add configure branch for SCO and HPUX
- avoid many warnings (unused variables, dead assignments, etc...)
- no fdopen for BeOS
- fix the Watcom fix for 32 bit mode (define FAR as empty)
- removed redefinition of Byte for MKWERKS
- work around an MWKERKS bug (incorrect merge of all .h files)

Changes in 0.99 (27 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
- fix the final (:-) bug for deflate with flush (output was correct but
  not completely flushed in rare occasions).
- default window size is same for compression and decompression
  (it's now sufficient to set MAX_WBITS in zconf.h).
- voidp -> voidpf and voidnp -> voidp (for consistency with other
  typedefs and because voidnp was not near in large model).

Changes in 0.94 (13 Aug 95)
- support MSDOS medium model
- fix deflate with flush (could sometimes generate bad output)
- fix deflateReset (zlib header was incorrectly suppressed)
- added support for VMS
- allow a compression level in gzopen()
- gzflush now calls fflush
- For deflate with flush, flush even if no more input is provided.
- rename libgz.a as libz.a
- avoid complex expression in infcodes.c triggering Turbo C bug
- work around a problem with gcc on Alpha (in INSERT_STRING)
- don't use inline functions (problem with some gcc versions)
- allow renaming of Byte, uInt, etc... with #define.
- avoid warning about (unused) pointer before start of array in deflate.c
- avoid various warnings in gzio.c, example.c, infblock.c, adler32.c, zutil.c
- avoid reserved word 'new' in trees.c

Changes in 0.93 (25 June 95)
- temporarily disable inline functions
- make deflate deterministic
- give enough lookahead for PARTIAL_FLUSH
- Set binary mode for stdin/stdout in minigzip.c for OS/2
- don't even use signed char in inflate (not portable enough)
- fix inflate memory leak for segmented architectures

Changes in 0.92 (3 May 95)
- don't assume that char is signed (problem on SGI)
- Clear bit buffer when starting a stored block
- no memcpy on Pyramid
- suppressed inftest.c
- optimized fill_window, put longest_match inline for gcc
- optimized inflate on stored blocks.
- untabify all sources to simplify patches

Changes in 0.91 (2 May 95)
- Default MEM_LEVEL is 8 (not 9 for Unix) as documented in zlib.h
- Document the memory requirements in zconf.h
- added "make install"
- fix sync search logic in inflateSync
- deflate(Z_FULL_FLUSH) now works even if output buffer too short
- after inflateSync, don't scare people with just "lo world"
- added support for DJGPP

Changes in 0.9 (1 May 95)
- don't assume that zalloc clears the allocated memory (the TurboC bug
  was Mark's bug after all :)
- let again gzread copy uncompressed data unchanged (was working in 0.71)
- deflate(Z_FULL_FLUSH), inflateReset and inflateSync are now fully implemented
- added a test of inflateSync in example.c
- moved MAX_WBITS to zconf.h because users might want to change that.
- document explicitly that zalloc(64K) on MSDOS must return a normalized
  pointer (zero offset)
- added Makefiles for Microsoft C, Turbo C, Borland C++
- faster crc32()

Changes in 0.8 (29 April 95)
- added fast inflate (inffast.c)
- deflate(Z_FINISH) now returns Z_STREAM_END when done. Warning: this
  is incompatible with previous versions of zlib which returned Z_OK.
- work around a TurboC compiler bug (bad code for b << 0, see infutil.h)
  (actually that was not a compiler bug, see 0.81 above)
- gzread no longer reads one extra byte in certain cases
- In gzio destroy(), don't reference a freed structure
- avoid many warnings for MSDOS
- avoid the ERROR symbol which is used by MS Windows

Changes in 0.71 (14 April 95)
- Fixed more MSDOS compilation problems :( There is still a bug with
  TurboC large model.

Changes in 0.7 (14 April 95)
- Added full inflate support.
- Simplified the crc32() interface. The pre- and post-conditioning
  (one's complement) is now done inside crc32(). WARNING: this is
  incompatible with previous versions; see zlib.h for the new usage.

Changes in 0.61 (12 April 95)
- workaround for a bug in TurboC. example and minigzip now work on MSDOS.

Changes in 0.6 (11 April 95)
- added minigzip.c
- added gzdopen to reopen a file descriptor as gzFile
- added transparent reading of non-gziped files in gzread.
- fixed bug in gzread (don't read crc as data)
- fixed bug in destroy (gzio.c) (don't return Z_STREAM_END for gzclose).
- don't allocate big arrays in the stack (for MSDOS)
- fix some MSDOS compilation problems

Changes in 0.5:
- do real compression in deflate.c. Z_PARTIAL_FLUSH is supported but
  not yet Z_FULL_FLUSH.
- support decompression but only in a single step (forced Z_FINISH)
- added opaque object for zalloc and zfree.
- added deflateReset and inflateReset
- added a variable zlib_version for consistency checking.
- renamed the 'filter' parameter of deflateInit2 as 'strategy'.
  Added Z_FILTERED and Z_HUFFMAN_ONLY constants.

Changes in 0.4:
- avoid "zip" everywhere, use zlib instead of ziplib.
- suppress Z_BLOCK_FLUSH, interpret Z_PARTIAL_FLUSH as block flush
  if compression method == 8.
- added adler32 and crc32
- renamed deflateOptions as deflateInit2, call one or the other but not both
- added the method parameter for deflateInit2.
- added inflateInit2
- simplied considerably deflateInit and inflateInit by not supporting
  user-provided history buffer. This is supported only in deflateInit2
  and inflateInit2.

Changes in 0.3:
- prefix all macro names with Z_
- use Z_FINISH instead of deflateEnd to finish compression.
- added Z_HUFFMAN_ONLY
- added gzerror()

                Frequently Asked Questions about zlib


If your question is not there, please check the zlib home page
http://zlib.net/ which may have more recent information.
The lastest zlib FAQ is at http://zlib.net/zlib_faq.html


 1. Is zlib Y2K-compliant?

    Yes. zlib doesn't handle dates.

 2. Where can I get a Windows DLL version?

    The zlib sources can be compiled without change to produce a DLL.  See the
    file win32/DLL_FAQ.txt in the zlib distribution.  Pointers to the
    precompiled DLL are found in the zlib web site at http://zlib.net/ .

 3. Where can I get a Visual Basic interface to zlib?

    See
        * http://marknelson.us/1997/01/01/zlib-engine/
        * win32/DLL_FAQ.txt in the zlib distribution

 4. compress() returns Z_BUF_ERROR.

    Make sure that before the call of compress(), the length of the compressed
    buffer is equal to the available size of the compressed buffer and not
    zero.  For Visual Basic, check that this parameter is passed by reference
    ("as any"), not by value ("as long").

 5. deflate() or inflate() returns Z_BUF_ERROR.

    Before making the call, make sure that avail_in and avail_out are not zero.
    When setting the parameter flush equal to Z_FINISH, also make sure that
    avail_out is big enough to allow processing all pending input.  Note that a
    Z_BUF_ERROR is not fatal--another call to deflate() or inflate() can be
    made with more input or output space.  A Z_BUF_ERROR may in fact be
    unavoidable depending on how the functions are used, since it is not
    possible to tell whether or not there is more output pending when
    strm.avail_out returns with zero.  See http://zlib.net/zlib_how.html for a
    heavily annotated example.

 6. Where's the zlib documentation (man pages, etc.)?

    It's in zlib.h .  Examples of zlib usage are in the files test/example.c
    and test/minigzip.c, with more in examples/ .

 7. Why don't you use GNU autoconf or libtool or ...?

    Because we would like to keep zlib as a very small and simple package.
    zlib is rather portable and doesn't need much configuration.

 8. I found a bug in zlib.

    Most of the time, such problems are due to an incorrect usage of zlib.
    Please try to reproduce the problem with a small program and send the
    corresponding source to us at zlib@gzip.org .  Do not send multi-megabyte
    data files without prior agreement.

 9. Why do I get "undefined reference to gzputc"?

    If "make test" produces something like

       example.o(.text+0x154): undefined reference to `gzputc'

    check that you don't have old files libz.* in /usr/lib, /usr/local/lib or
    /usr/X11R6/lib. Remove any old versions, then do "make install".

10. I need a Delphi interface to zlib.

    See the contrib/delphi directory in the zlib distribution.

11. Can zlib handle .zip archives?

    Not by itself, no.  See the directory contrib/minizip in the zlib
    distribution.

12. Can zlib handle .Z files?

    No, sorry.  You have to spawn an uncompress or gunzip subprocess, or adapt
    the code of uncompress on your own.

13. How can I make a Unix shared library?

    By default a shared (and a static) library is built for Unix.  So:

    make distclean
    ./configure
    make

14. How do I install a shared zlib library on Unix?

    After the above, then:

    make install

    However, many flavors of Unix come with a shared zlib already installed.
    Before going to the trouble of compiling a shared version of zlib and
    trying to install it, you may want to check if it's already there!  If you
    can #include <zlib.h>, it's there.  The -lz option will probably link to
    it.  You can check the version at the top of zlib.h or with the
    ZLIB_VERSION symbol defined in zlib.h .

15. I have a question about OttoPDF.

    We are not the authors of OttoPDF. The real author is on the OttoPDF web
    site: Joel Hainley, jhainley@myndkryme.com.

16. Can zlib decode Flate data in an Adobe PDF file?

    Yes. See http://www.pdflib.com/ . To modify PDF forms, see
    http://sourceforge.net/projects/acroformtool/ .

17. Why am I getting this "register_frame_info not found" error on Solaris?

    After installing zlib 1.1.4 on Solaris 2.6, running applications using zlib
    generates an error such as:

        ld.so.1: rpm: fatal: relocation error: file /usr/local/lib/libz.so:
        symbol __register_frame_info: referenced symbol not found

    The symbol __register_frame_info is not part of zlib, it is generated by
    the C compiler (cc or gcc).  You must recompile applications using zlib
    which have this problem.  This problem is specific to Solaris.  See
    http://www.sunfreeware.com for Solaris versions of zlib and applications
    using zlib.

18. Why does gzip give an error on a file I make with compress/deflate?

    The compress and deflate functions produce data in the zlib format, which
    is different and incompatible with the gzip format.  The gz* functions in
    zlib on the other hand use the gzip format.  Both the zlib and gzip formats
    use the same compressed data format internally, but have different headers
    and trailers around the compressed data.

19. Ok, so why are there two different formats?

    The gzip format was designed to retain the directory information about a
    single file, such as the name and last modification date.  The zlib format
    on the other hand was designed for in-memory and communication channel
    applications, and has a much more compact header and trailer and uses a
    faster integrity check than gzip.

20. Well that's nice, but how do I make a gzip file in memory?

    You can request that deflate write the gzip format instead of the zlib
    format using deflateInit2().  You can also request that inflate decode the
    gzip format using inflateInit2().  Read zlib.h for more details.

21. Is zlib thread-safe?

    Yes.  However any library routines that zlib uses and any application-
    provided memory allocation routines must also be thread-safe.  zlib's gz*
    functions use stdio library routines, and most of zlib's functions use the
    library memory allocation routines by default.  zlib's *Init* functions
    allow for the application to provide custom memory allocation routines.

    Of course, you should only operate on any given zlib or gzip stream from a
    single thread at a time.

22. Can I use zlib in my commercial application?

    Yes.  Please read the license in zlib.h.

23. Is zlib under the GNU license?

    No.  Please read the license in zlib.h.

24. The license says that altered source versions must be "plainly marked". So
    what exactly do I need to do to meet that requirement?

    You need to change the ZLIB_VERSION and ZLIB_VERNUM #defines in zlib.h.  In
    particular, the final version number needs to be changed to "f", and an
    identification string should be appended to ZLIB_VERSION.  Version numbers
    x.x.x.f are reserved for modifications to zlib by others than the zlib
    maintainers.  For example, if the version of the base zlib you are altering
    is "1.2.3.4", then in zlib.h you should change ZLIB_VERNUM to 0x123f, and
    ZLIB_VERSION to something like "1.2.3.f-zachary-mods-v3".  You can also
    update the version strings in deflate.c and inftrees.c.

    For altered source distributions, you should also note the origin and
    nature of the changes in zlib.h, as well as in ChangeLog and README, along
    with the dates of the alterations.  The origin should include at least your
    name (or your company's name), and an email address to contact for help or
    issues with the library.

    Note that distributing a compiled zlib library along with zlib.h and
    zconf.h is also a source distribution, and so you should change
    ZLIB_VERSION and ZLIB_VERNUM and note the origin and nature of the changes
    in zlib.h as you would for a full source distribution.

25. Will zlib work on a big-endian or little-endian architecture, and can I
    exchange compressed data between them?

    Yes and yes.

26. Will zlib work on a 64-bit machine?

    Yes.  It has been tested on 64-bit machines, and has no dependence on any
    data types being limited to 32-bits in length.  If you have any
    difficulties, please provide a complete problem report to zlib@gzip.org

27. Will zlib decompress data from the PKWare Data Compression Library?

    No.  The PKWare DCL uses a completely different compressed data format than
    does PKZIP and zlib.  However, you can look in zlib's contrib/blast
    directory for a possible solution to your problem.

28. Can I access data randomly in a compressed stream?

    No, not without some preparation.  If when compressing you periodically use
    Z_FULL_FLUSH, carefully write all the pending data at those points, and
    keep an index of those locations, then you can start decompression at those
    points.  You have to be careful to not use Z_FULL_FLUSH too often, since it
    can significantly degrade compression.  Alternatively, you can scan a
    deflate stream once to generate an index, and then use that index for
    random access.  See examples/zran.c .

29. Does zlib work on MVS, OS/390, CICS, etc.?

    It has in the past, but we have not heard of any recent evidence.  There
    were working ports of zlib 1.1.4 to MVS, but those links no longer work.
    If you know of recent, successful applications of zlib on these operating
    systems, please let us know.  Thanks.

30. Is there some simpler, easier to read version of inflate I can look at to
    understand the deflate format?

    First off, you should read RFC 1951.  Second, yes.  Look in zlib's
    contrib/puff directory.

31. Does zlib infringe on any patents?

    As far as we know, no.  In fact, that was originally the whole point behind
    zlib.  Look here for some more information:

    http://www.gzip.org/#faq11

32. Can zlib work with greater than 4 GB of data?

    Yes.  inflate() and deflate() will process any amount of data correctly.
    Each call of inflate() or deflate() is limited to input and output chunks
    of the maximum value that can be stored in the compiler's "unsigned int"
    type, but there is no limit to the number of chunks.  Note however that the
    strm.total_in and strm_total_out counters may be limited to 4 GB.  These
    counters are provided as a convenience and are not used internally by
    inflate() or deflate().  The application can easily set up its own counters
    updated after each call of inflate() or deflate() to count beyond 4 GB.
    compress() and uncompress() may be limited to 4 GB, since they operate in a
    single call.  gzseek() and gztell() may be limited to 4 GB depending on how
    zlib is compiled.  See the zlibCompileFlags() function in zlib.h.

    The word "may" appears several times above since there is a 4 GB limit only
    if the compiler's "long" type is 32 bits.  If the compiler's "long" type is
    64 bits, then the limit is 16 exabytes.

33. Does zlib have any security vulnerabilities?

    The only one that we are aware of is potentially in gzprintf().  If zlib is
    compiled to use sprintf() or vsprintf(), then there is no protection
    against a buffer overflow of an 8K string space (or other value as set by
    gzbuffer()), other than the caller of gzprintf() assuring that the output
    will not exceed 8K.  On the other hand, if zlib is compiled to use
    snprintf() or vsnprintf(), which should normally be the case, then there is
    no vulnerability.  The ./configure script will display warnings if an
    insecure variation of sprintf() will be used by gzprintf().  Also the
    zlibCompileFlags() function will return information on what variant of
    sprintf() is used by gzprintf().

    If you don't have snprintf() or vsnprintf() and would like one, you can
    find a portable implementation here:

        http://www.ijs.si/software/snprintf/

    Note that you should be using the most recent version of zlib.  Versions
    1.1.3 and before were subject to a double-free vulnerability, and versions
    1.2.1 and 1.2.2 were subject to an access exception when decompressing
    invalid compressed data.

34. Is there a Java version of zlib?

    Probably what you want is to use zlib in Java. zlib is already included
    as part of the Java SDK in the java.util.zip package. If you really want
    a version of zlib written in the Java language, look on the zlib home
    page for links: http://zlib.net/ .

35. I get this or that compiler or source-code scanner warning when I crank it
    up to maximally-pedantic. Can't you guys write proper code?

    Many years ago, we gave up attempting to avoid warnings on every compiler
    in the universe.  It just got to be a waste of time, and some compilers
    were downright silly as well as contradicted each other.  So now, we simply
    make sure that the code always works.

36. Valgrind (or some similar memory access checker) says that deflate is
    performing a conditional jump that depends on an uninitialized value.
    Isn't that a bug?

    No.  That is intentional for performance reasons, and the output of deflate
    is not affected.  This only started showing up recently since zlib 1.2.x
    uses malloc() by default for allocations, whereas earlier versions used
    calloc(), which zeros out the allocated memory.  Even though the code was
    correct, versions 1.2.4 and later was changed to not stimulate these
    checkers.

37. Will zlib read the (insert any ancient or arcane format here) compressed
    data format?

    Probably not. Look in the comp.compression FAQ for pointers to various
    formats and associated software.

38. How can I encrypt/decrypt zip files with zlib?

    zlib doesn't support encryption.  The original PKZIP encryption is very
    weak and can be broken with freely available programs.  To get strong
    encryption, use GnuPG, http://www.gnupg.org/ , which already includes zlib
    compression.  For PKZIP compatible "encryption", look at
    http://www.info-zip.org/

39. What's the difference between the "gzip" and "deflate" HTTP 1.1 encodings?

    "gzip" is the gzip format, and "deflate" is the zlib format.  They should
    probably have called the second one "zlib" instead to avoid confusion with
    the raw deflate compressed data format.  While the HTTP 1.1 RFC 2616
    correctly points to the zlib specification in RFC 1950 for the "deflate"
    transfer encoding, there have been reports of servers and browsers that
    incorrectly produce or expect raw deflate data per the deflate
    specification in RFC 1951, most notably Microsoft.  So even though the
    "deflate" transfer encoding using the zlib format would be the more
    efficient approach (and in fact exactly what the zlib format was designed
    for), using the "gzip" transfer encoding is probably more reliable due to
    an unfortunate choice of name on the part of the HTTP 1.1 authors.

    Bottom line: use the gzip format for HTTP 1.1 encoding.

40. Does zlib support the new "Deflate64" format introduced by PKWare?

    No.  PKWare has apparently decided to keep that format proprietary, since
    they have not documented it as they have previous compression formats.  In
    any case, the compression improvements are so modest compared to other more
    modern approaches, that it's not worth the effort to implement.

41. I'm having a problem with the zip functions in zlib, can you help?

    There are no zip functions in zlib.  You are probably using minizip by
    Giles Vollant, which is found in the contrib directory of zlib.  It is not
    part of zlib.  In fact none of the stuff in contrib is part of zlib.  The
    files in there are not supported by the zlib authors.  You need to contact
    the authors of the respective contribution for help.

42. The match.asm code in contrib is under the GNU General Public License.
    Since it's part of zlib, doesn't that mean that all of zlib falls under the
    GNU GPL?

    No.  The files in contrib are not part of zlib.  They were contributed by
    other authors and are provided as a convenience to the user within the zlib
    distribution.  Each item in contrib has its own license.

43. Is zlib subject to export controls?  What is its ECCN?

    zlib is not subject to export controls, and so is classified as EAR99.

44. Can you please sign these lengthy legal documents and fax them back to us
    so that we can use your software in our product?

    No. Go away. Shoo.