/usr/lib/swi-prolog/library/zlib.pl is in swi-prolog-nox 7.6.4+dfsg-1build1.
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1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 | /* Part of SWI-Prolog
Author: Jan Wielemaker
E-mail: J.Wielemaker@vu.nl
WWW: http://www.swi-prolog.org
Copyright (c) 2006-2016, University of Amsterdam
VU University Amsterdam
All rights reserved.
Redistribution and use in source and binary forms, with or without
modification, are permitted provided that the following conditions
are met:
1. Redistributions of source code must retain the above copyright
notice, this list of conditions and the following disclaimer.
2. Redistributions in binary form must reproduce the above copyright
notice, this list of conditions and the following disclaimer in
the documentation and/or other materials provided with the
distribution.
THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
"AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
POSSIBILITY OF SUCH DAMAGE.
*/
:- module(zlib,
[ zopen/3, % +Stream, -ZStream, +Option
gzopen/3, % +File, +Mode, -Stream
gzopen/4 % +File, +Mode, -Stream, +Options
]).
:- use_module(library(shlib)).
:- use_module(library(error)).
:- use_module(library(apply)).
:- use_module(library(option)).
:- predicate_options(zopen/3, 3,
[ format(oneof([gzip,deflate])),
multi_part(boolean),
close_parent(boolean),
level(between(0,9))
]).
:- predicate_options(gzopen/4, 4,
[ pass_to(zopen/3, 3),
pass_to(system:open/4, 4)
]).
/** <module> Zlib wrapper for SWI-Prolog
Read/write compressed data based on the zlib library.
@author Jan Wielemaker
@see http://www.zlib.net/
@see http://www.swi-prolog.org/packages/zlib.html
*/
:- use_foreign_library(foreign(zlib4pl)).
:- public zdebug/1. % Set debug level
%! gzopen(+File, +Mode, -Stream) is det.
%! gzopen(+File, +Mode, -Stream, +Options) is det.
%
% Open a file compatible with the gzip program. Note that if a
% file is opened in =append= mode, a second gzip image will be
% added to the end of the file. The gzip standard defines that a
% file can hold multiple gzip images and inflating the file
% results in a concatenated stream of all inflated images.
%
% Options are passed to open/4 and zopen/3. Default format is
% =gzip=.
gzopen(File, Mode, Stream) :-
gzopen(File, Mode, Stream, []).
gzopen(File, Mode, Stream, Options) :-
must_be(oneof([read,write,append]), Mode),
partition(zoption, Options, ZOptions0, OpenOptions),
merge_options(ZOptions0,
[ format(gzip),
close_parent(true)
], ZOptions),
open(File, Mode, Stream0, OpenOptions),
zopen(Stream0, Stream, ZOptions),
set_stream(Stream, file_name(File)),
( option(alias(Alias), ZOptions)
-> set_stream(Stream, alias(Alias))
; true
).
zoption(format(_)).
zoption(multi_part(_)).
zoption(level(_)).
zoption(alias(_)).
%! http:encoding_filter(+Encoding, +In0, -In) is semidet.
%
% Act as plugin for library(http/http_open) for processing content
% with =|Content-encoding: gzip|=
http:encoding_filter(gzip, In0, In) :-
zopen(In0, In,
[ close_parent(true)
]).
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