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--  UnZip.Decompress
--------------------
--  Private, internal to the UnZip package.
--  See root package (UnZip) for details & credits.

--  Legal licensing note:

--  Copyright (c) 2007 .. 2024 Gautier de Montmollin
--  SWITZERLAND

--  Permission is hereby granted, free of charge, to any person obtaining a copy
--  of this software and associated documentation files (the "Software"), to deal
--  in the Software without restriction, including without limitation the rights
--  to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
--  copies of the Software, and to permit persons to whom the Software is
--  furnished to do so, subject to the following conditions:

--  The above copyright notice and this permission notice shall be included in
--  all copies or substantial portions of the Software.

--  THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
--  IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
--  FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
--  AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
--  LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
--  OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
--  THE SOFTWARE.

--  NB: this is the MIT License, as found on the site
--  http://www.opensource.org/licenses/mit-license.php

---------------------
--
--  Created 9-Mar-2007
--
--  This package includes the decompression algorithms for methods
--  Store, Reduce, Shrink (LZW), Implode, Deflate, BZip2 and LZMA.
--
--  The package body contains the packages UnZ_IO, UnZ_Glob, UnZ_Infl,
--  UnZ_Olds and UnZ_Misc that were separate in previous versions of Zip-Ada.
--  They became local packages inside the Decompress_Data procedure.
--  Previously global variables are since then local and task-safe
--  with one copy per concurrent call.

with Zip.Headers;
with Zip_Streams;

with Ada.Strings.Unbounded;

private package UnZip.Decompress is

  procedure Decompress_Data
    (zip_file                   : in out Zip_Streams.Root_Zipstream_Type'Class;
     --  zip_file must be open and its index is meant
     --  to point to the beginning of compressed data
     format                     : in     Zip.PKZip_method;
     write_mode                 : in     Write_Mode_Type;
     output_file_name           : in     String;  --  relevant only if mode = write_to_file
     output_memory_access       :    out p_Stream_Element_Array;  -- \ = write_to_memory
     output_stream_access       : in     p_Stream;                -- \ = write_to_stream
     feedback                   : in     Zip.Feedback_Proc;
     explode_literal_tree       : in     Boolean;  --  relevant for the "explode" format
     explode_slide_8KB_LZMA_EOS : in     Boolean;  --  relevant for the "explode" and "LZMA" formats
     data_descriptor_after_data : in     Boolean;
     is_encrypted               : in     Boolean;
     password                   : in out Ada.Strings.Unbounded.Unbounded_String;
     get_new_password           : in     Get_Password_Proc;  --  if null, initial pwd must fit
     hint                       : in out Zip.Headers.Local_File_Header);
     --
     --  Values are known, or smart fakes, and are later corrected if a closing
     --  Data_descriptor is appended to the compressed data (1-pass written
     --  zip files, like JAR, OpenDocument, etc.)

private

  --  When deflate_strict = True, stop if there is an incomplete Huffman
  --  code set for decoding LZ distances. This is the correct and safe behaviour.
  --  When dealing with Zip files from some old compression programs like PKZIP 1.93a,
  --  the check can be bypassed with deflate_strict = False, but this lessens the
  --  data error detection.
  --
  deflate_strict : constant Boolean := True;

  --  Primitive tracing using Ada.Text_IO, plus a few statistics
  --
  type Trace_type is (none, some_t, full);

  trace : constant Trace_type := none; --  <==  Choice is here

  no_trace   : constant Boolean := trace = none;
  some_trace : constant Boolean := trace >= some_t;
  full_trace : constant Boolean := trace = full;

end UnZip.Decompress;