% \iffalse meta-comment
% ======================================================================
% scrwfile.dtx
% Copyright (c) Markus Kohm, 2010-2022
%
% This file is part of the LaTeX2e KOMA-Script bundle.
%
% This work may be distributed and/or modified under the conditions of
% the LaTeX Project Public License, version 1.3c of the license.
% The latest version of this license is in
%   http://www.latex-project.org/lppl.txt
% and version 1.3c or later is part of all distributions of LaTeX
% version 2005/12/01 and of this work.
%
% This work has the LPPL maintenance status "author-maintained".
%
% The Current Maintainer and author of this work is Markus Kohm.
%
% This work consists of all files listed in MANIFEST.md.
% ======================================================================
%%% From File: $Id: scrwfile.dtx 3889 2022-06-09 12:11:14Z kohm $
%<*dtx>
\ifx\ProvidesFile\undefined\def\ProvidesFile#1[#2]{}\fi
\ProvidesFile{scrwfile.dtx}
%</dtx>
%<(package&identify)|driver>\NeedsTeXFormat{LaTeX2e}[1995/06/01]
%<package&identify>\ProvidesPackage{scrwfile}
%<driver>\ProvidesFile{scrwfile.drv}
%<*dtx|(package&identify)|driver>
  [2021/05/30 v0.1.10 KOMA-Script package (write and clone files)]
%</dtx|(package&identify)|driver>
%<*dtx>
\ifx\documentclass\undefined
  \input scrdocstrip.tex
  \@@input scrkernel-version.dtx
  \@@input scrstrip.inc
  \KOMAdefVariable{COPYRIGHTFROM}{2010}

  \generate{\usepreamble\defaultpreamble
    \file{scrwfile.sty}{%
      \from{scrwfile.dtx}{package,scrwfile,identify,option,body}%
      \from{scrlogo.dtx}{logo}%
    }%
  }

  \@@input scrstrop.inc
\else
  \let\endbatchfile\relax
\fi
\endbatchfile
%</dtx>
%<*driver>
\documentclass[USenglish]{koma-script-source-doc}
\usepackage{babel}
\usepackage{hvlogos}
\setcounter{StandardModuleDepth}{2}
\begin{document}
\DocInput{scrwfile.dtx}
\end{document}
%</driver>
% \fi
%
% \changes{v0.1}{2010/10/01}{start of new package}
% \changes{v0.1.7}{2014/10/13}{manual moved to \KOMAScript{} manual}
% \changes{v0.1.9}{2021/05/30}{version number scheme changed}
% \changes{v0.1.10}{2022/02/05}{switch over from \cls*{scrdoc} to
%   \cls*{koma-script-source-doc}}
%
% \GetFileInfo{scrwfile.dtx}
% \title{Saving Write Handles with the Experimental
%   \href{https://komascript.de}{\KOMAScript} Package \pkg*{scrwfile}}
% \author{\href{mailto:komascript@gmx.info}{Markus Kohm}}
% \date{Version \fileversion{} of \filedate}
% \maketitle
% \begin{abstract}
%   The \TeX{} engines \TeX, \pdfTeX, and \XeTeX{} (but not \LuaTeX) do
%   provide only 16 handles for simultaneously write open files. Some of them
%   are already used by \LaTeX{}. Moreover, for every file using
%   \cs{@starttoc} \LaTeX{} keeps a write file open from usage of
%   \cs{@starttoc}, e.g., inside \cs{tableofcontents}, \cs{listoffigures}
%   etc., until the end of the document. Additional write files are used for
%   the index, glossary etc. So sometimes it happens, that there are not
%   enough handles to open another one. \pkg*{scrwfile} was made to change the
%   \LaTeX{} internal handling of all the helper files bases on \cs{@starttoc}
%   to not keep them open simultaneously, but use only one file handle for all
%   of them. So you should never run out of write file handles.
% \end{abstract}
% 
% \section{User Manual}
%
% You can find the user manual of \pkg*{scrwfile} in the \KOMAScript{} manual,
% either the German \file{scrguide} or the English \file{scrguien}. But please
% note:
% \begin{quote}\bfseries
%   This is an experimental package. Usage of this package is on your own
%   risk. There is no support, if you are using this package, not only for
%   this package but also for the class you are using or other packages, that
%   use \cs{@starttoc} or \cs{@writefile} like \pkg{caption}, \pkg{float},
%   \pkg*{tocbasic}, \pkg{listings} and many more.
% \end{quote}
%
% \MaybeStop{\PrintIndex}
%
%
% \section{Implementation of \pkg*{scrwfile}}
%
%    \begin{macrocode}
%<*package>
%    \end{macrocode}
%
%    \begin{macrocode}
%<*identify>
\PackageWarningNoLine{scrwfile}{%
  THIS IS AN EXPERIMENTAL PACKAGE!\MessageBreak
  USAGE OF THIS PACKAGE IS ON YOUR OWN RISK!\MessageBreak
  EVERYTHING MAY HAPPEN!\MessageBreak
  EVERYTHING MAY CHANGE IN FUTURE!\MessageBreak
  THERE IS NO SUPPORT, IF YOU USE THIS PACKAGE!\MessageBreak
  Maybe, it would be better not to load this package%
}
%</identify>
%    \end{macrocode}
%\iffalse
%\fi
%
% \subsection{Options}
% \iffalse
%<*option>
% \fi
% Currently we don't need options.
% \iffalse
%</option>
% \fi
%
% \subsection{Body}
%    \begin{macrocode}
%<*body>
%    \end{macrocode}
%
% \subsubsection{Needed Packages}
%
% Package \pkg*{scrbase} is needed, because of using several \KOMAScript{}
% basic commands.
%    \begin{macrocode}
\RequirePackage{scrbase}[2010/09/17]
%    \end{macrocode}
%
% Package \pkg*{scrlfile} is needed because of the \file{aux}-file
% handling and \cs{protected@immediate@write}.
%    \begin{macrocode}
\RequirePackage{scrlfile}[2010/09/30]
%    \end{macrocode}
%
% \changes{v0.1.10}{2022/02/04}{\pkg{iftex} is required}
% Package \pkg{iftex} is used to detect Lua\LaTeX.
%    \begin{macrocode}
\RequirePackage{iftex}
%    \end{macrocode}
%
% \subsubsection{Is is needed?}
%
% \changes{v0.1.9}{2021/05/30}{with Lua\LaTeX{} using is not recommended}
% \changes{v0.1.10}{2022/02/04}{using \cs{ifluatex}}
% \changes{v0.1.10}{2022/02/04}{\cs{PackageInfoNoLine} replaced by
% \cs{PackageWarningNoLine}}
% If the user uses Lua\LaTeX{} usage of \pkg*{scrwfile} should not be
% needed.
%    \begin{macrocode}
\ifluatex
  \PackageWarningNoLine{scrwfile}{LuaLaTeX detected.\MessageBreak
    With LuaLaTeX you should never get an error message:\MessageBreak
    \space\space`No room for a new \string\write'.\MessageBreak
    So scrwfile could make much more harm than benefit\MessageBreak
    and using it is not recommended}%
\fi
%    \end{macrocode}
%
% \subsubsection{\LaTeX{} Kernel Patchs}
%
% For some features we need to patch \LaTeX{} kernel macros. Those features
% and macros are:
% \begin{description}
% \item[Single handle feature] means, that \LaTeX{} will no longer need a file
%   handle for every help file, but only one for all files. We will patch
%  \cs{@starttoc} and \cs{@writefile} to do so.
% \item[Clone file feature] means, that every write to one file may be done to
%   another file, too. We will patch \cs{@writefile} to do so.
% \end{description}
% Every patch should be minimum invasive, so that files, that are not under
% \pkg*{scrwfile}'s control are changed as little as possible.
%
% \begin{macro}{\scrwfile@if@only}
% First of all we check, if the file should be handled by \pkg*{scrwfile}.
%    \begin{macrocode}
\newcommand*{\scrwfile@if@only}[1]{%
  \begingroup
    \scr@ifundefinedorrelax{scrwfile@only}{\@tempswatrue}{%
      \@tempswafalse
      \edef\reserved@b{#1}%
      \@for\reserved@a:=\scrwfile@only\do
        {\ifx\reserved@a\reserved@b\@tempswatrue\fi}%
    }%
    \if@tempswa
      \scr@ifundefinedorrelax{scrwfile@never}{}{%
        \edef\reserved@b{#1}%
        \@for\reserved@a:=\scrwfile@never\do
          {\ifx\reserved@a\reserved@b\@tempswafalse\fi}%
      }%
    \fi
  \expandafter\endgroup
  \if@tempswa
    \expandafter\@firstoftwo
  \else
    \expandafter\@secondoftwo
  \fi
}
%    \end{macrocode}
% \end{macro}
%
% \begin{macro}{\scrwfile@starttoc,\scrwfile@@starttoc}
% This is the internal redefinition of \cs{@starttoc}. First of all test, if it
% should be used, then use it or not.
%    \begin{macrocode}
\newcommand*{\scrwfile@starttoc}[1]{%
  \scrwfile@if@only{#1}{\scrwfile@@starttoc}{\scrwfile@saved@starttoc}{#1}%
}
\newcommand*{\scrwfile@@starttoc}[1]{%
%<trace>  \PackageInfo{scrwfile}{%
%<trace>    Using my own \string\@starttoc\space for `#1'}%
  \begingroup
    \if@filesw
      \xdef\scrwfile@writefilelist{\scrwfile@writefilelist,#1}%
    \fi
    \@fileswfalse
    \scrwfile@saved@starttoc{#1}%
  \endgroup
}
%    \end{macrocode}
% \end{macro}
%
% \begin{macro}{\scrwfile@writefile,\scrwfile@@writefile,\scrwfile@wrtout,
%               \scrwfile@writefilelist}
% This is the internal redefinition of \cs{@writefile}. First of all test, if
% it should be used, then use it or not.
%    \begin{macrocode}
\newcommand*{\scrwfile@writefile}[1]{%
  \scrwfile@if@only{#1}{\scrwfile@@writefile}{\scrwfile@saved@writefile}{#1}%
}
\newcommand{\scrwfile@@writefile}[2]{%
%<trace>  \PackageInfo{scrwfile}{%
%<trace>    Using my own \string\@writefile\space for `#1'}%
  \ifnum\scrwfile@wrtout>0
    \begingroup
      \@temptokena{#2}%
      \immediate\write\scrwfile@wrtout{%
        \string\@writefile{#1}{\the\@temptokena}%
      }%
%    \end{macrocode}
% This was the entry for the real file. But we also may have clone files:
%    \begin{macrocode}
      \scrwfile@process@clones{#1}%
    \endgroup
  \fi
}
\chardef\scrwfile@wrtout\z@
\newcommand*{\scrwfile@writefilelist}{}
%    \end{macrocode}
% \end{macro}
%
% \begin{macro}{\@writefile,\scrwfile@saved@writefile}
% We have to add the single handle feature and the clone file feature to
% \cs{@writefile} and therefore save the original
% definition. \cs{scrwfile@saved@writefile} is used, whenever a file is not
% under \pkg*{scrwfile}'s control.
%    \begin{macrocode}
\newcommand*{\scrwfile@saved@writefile}{}
\BeforeClosingMainAux{%
  \ifx\scrwfile@writefilelist\@empty\else
    \let\scrwfile@saved@writefile\@writefile
    \let\scrwfile@wrtout\@partaux
    \immediate\openout\scrwfile@wrtout \jobname.wrt
    \let\@writefile\scrwfile@writefile
  \fi
}
\AfterReadingMainAux{%
  \ifx\scrwfile@writefilelist\@empty\else
    \immediate\closeout\scrwfile@wrtout
    \chardef\scrwfile@wrtout\z@
    \begingroup
      \let\@writefile\scrwfile@saved@writefile
      \@for\@currext:=\scrwfile@writefilelist\do{%
        \begingroup
          \ifx\@currext\@empty\else
            \scr@ifundefinedorrelax{tf@\@currext}{%
%<trace>              \typeout{Process extension: `\@currext'}
              \immediate\openout\@partaux \jobname.\@currext
              \expandafter\let\csname tf@\@currext\endcsname\@partaux
              \@input@{\jobname.wrt}%
              \immediate\closeout\@partaux
            }{}%
          \fi
        \endgroup
      }%
    \endgroup
  \fi
}
%    \end{macrocode}
% \changes{v0.1.8}{2021/05/30}{added order rule for
%   \pkg*{scrlayer-notecolumn}}
% Note: Here we use a \LaTeX{} version test, because a do-nothing-definition
% like the one of \pkg{latexrelease} wouldn't be correct, if the command is
% not supported by the current \LaTeX{} kernel version setting.
%    \begin{macrocode}
\IfLTXAtLeastTF{2020/10/01}{%
  \DeclareHookRule{enddocument/afteraux}%
                  {scrwfile}{before}{scrlayer-notecolumn}%
}{%
  \@ifpackageloaded{scrlayer-notecolumn}{%
    \PackageWarningNoLine{scrwfile}{%
      Dangerous package order detected!\MessageBreak
      As a general rule, you should load scrwfile as soon\MessageBreak
      as possible, maybe even before `\string\documentclass'\MessageBreak
      (using `\string\RequirePackage' instead of
      `\string\usepackage').\MessageBreak
      Following packages should be loaded after scrwfile:\MessageBreak
      \space - scrlayer-notecolumn}%
  }{}%
}
%    \end{macrocode}
% \end{macro}
%
% \begin{macro}{\@starttoc,\scrwfile@saved@starttoc}
% We have to add the single handle feature to \cs{@starttoc} and therefore
% save the original definition.
% \changes{v0.1.5}{2013/07/24}{take care for unfriendly \textsl{hyperref}}
% \cs{scrwfile@saved@starttoc} is be used, whenever the file is not under
% \pkg*{scrwfile}'s control. Because of package \textsl{hyperref}, that does
% a hard redefinition without any care for changed definitions, we have to
% take care for that unfriendly package and cannot do a simple
% \begin{verbatim}
% \let\scrwfile@saved@starttoc\@starttoc
% \let\@starttoc\scrwfile@starttoc
% \end{verbatim}
%    \begin{macrocode}
\newcommand*{\scrwfile@saved@starttoc}{}
\AtBeginDocument{%
  \begingroup
    \@ifpackageloaded{hyperref}{%
      \scr@ifundefinedorrelax{Hy@AtBeginDocument}{%
        \PackageWarning{scrwfile}{%
          Incompatible `hyperref` package detected!\MessageBreak
          You are using a `hyperref` version, that\MessageBreak
          doesn't provide `\string\Hy@AtBeginDocument`.\MessageBreak
          This may or may not work.\MessageBreak
          Using immediate redefinition%
        }%
        \aftergroup\@firstofone
      }{%
        \def\reserved@a{\AtBeginDocument}%
        \ifx\Hy@AtBeginDocumentHook\@undefined
          \PackageInfo{scrwfile}{%
            Using immediate redefinition%
          }%
          \aftergroup\@firstofone
        \else
          \PackageInfo{scrwfile}{%
            Using `\string\Hy@AtBeginDocument`%
          }%
          \aftergroup\Hy@AtBeginDocument
        \fi
      }%
    }{%
      \aftergroup\@firstofone
    }%
  \endgroup
  {%
    \PackageInfo{scrwfile}{%
      Extending `\string\@starttoc`
    }%
    \let\scrwfile@saved@starttoc\@starttoc
    \let\@starttoc\scrwfile@starttoc
  }%
}
%    \end{macrocode}
% \end{macro}
%
%
% \subsubsection{Clone TOC Feature}
%
% \pkg*{scrwfile} may clone a TOC, that means, every entry to one file will
% be copied to other files, too.  You must not clone recursively!
%
% \begin{description}
% \item[ToDo:]The whole feature should be moved to \pkg*{tocbasic}. But this
%   would need a complete re-implementation and would result in one more write
%   handle for every cloned file. So maybe it wouldn't be a really good idea
%   to do so.
% \end{description}
%
% \begin{macro}{\scrwfile@process@clones}
%    \begin{macrocode}
\newcommand*{\scrwfile@process@clones}[1]{%
  \scr@ifundefinedorrelax{scrwfile@clone@#1}{}{%
    \begingroup
      \let\@@protect\protect\let\protect\@empty\afterassignment\restore@protect
      \edef\reserved@b{\csname scrwfile@clone@#1\endcsname}%
      \edef\reserved@c{,#1}%
      \@for \reserved@a:=\reserved@b\do {%
        \@tempswatrue
        \@for \reserved@d:=\reserved@c\do {%
          \ifx\reserved@d\reserved@a\@tempswafalse\fi
        }%
        \if@tempswa
%<trace>          \typeout{clone entry from `#1' to `\reserved@a'}%
          \immediate\write\scrwfile@wrtout{%
            \string\@writefile{\reserved@a}{\the\@temptokena}%
          }%
          \edef\reserved@c{\reserved@c,\reserved@a}%
        \fi
      }%
    \endgroup
  }%
}%
%    \end{macrocode}
% \end{macro}
%
% \begin{command}{\TOCclone}
% \changes{v0.1.8}{2019/11/18}{\cs{ifstr} umbenannt in \cs{Ifstr}}
% \changes{v0.1.8}{2019/11/19}{\cs{ifattoclist} replaced by \cs{Ifattoclist}}
% \changes{v0.1.8}{2019/11/19}{\cs{iftocfeature} replaced by
%   \cs{Iftocfeature}}
% \changes{v0.1.8}{2020/02/25}{spurious space in warning message removed}
% \changes{v0.1.9}{2021/05/30}{requires package \pkg*{tocbasic}}
% \changes{v0.1.9}{2021/05/30}{can be used only in preamble}
% Clone the entries from the second (first mandatory) argument TOC to the
% third (second mandatory) argument TOC.  If the first (optional) argument was
% given, define |\listof#3name| to this and also define |\listof#3| and clone
% the toc features \texttt{leveldown}, \texttt{numbered}, \texttt{onecolumn}
% and \texttt{totoc} of |#2| to |#3|. The toc feature \texttt{nobabel} will
% always be set, because the babel entries at TOC |#3| will be cloned from TOC
% |#2|.
% \begin{description}
% \item{Note:} We use owner \texttt{TOCclone} for all cloned extensions.
% \end{description}
%    \begin{macrocode}
\newcommand*{\TOCclone}[3][]{%
  \RequirePackage{tocbasic}%
  \scr@ifundefinedorrelax{scrwfile@clone@#2}{%
    \expandafter\protected@edef\csname scrwfile@clone@#2\endcsname{%
      #3,\protect\csname scrwfile@clone@#3\endcsname
    }%
  }{%
    \edef\reserved@b{\csname scrwfile@clone@#2\endcsname}%
    \expandafter\protected@edef\csname scrwfile@clone@#2\endcsname{%
      \csname scrwfile@clone@#2\endcsname,%
      #3,%
      \protect\csname scrwfile@clone@#3\endcsname
    }%
  }%
  \scr@ifundefinedorrelax{scrwfile@clone@#3}{%
    \expandafter\let\csname scrwfile@clone@#3\endcsname\@empty
  }{}%
  \Ifattoclist{#3}{%
    \PackageWarning{scrwfile}{`#3' already under control of
      tocbasic.\MessageBreak
      Nevertheless features will be set%
    }%
  }{%
    \addtotoclist[TOCclone]{#3}%
  }%
  \setuptoc{#3}{nobabel}%
  \Ifstr{#1}{}{%
  }{%
    \@namedef{listof#3name}{#1}%
    \@namedef{listof#3}{\listoftoc{#3}}%
    \Iftocfeature{#2}{leveldown}{\setuptoc{#3}{leveldown}}{}%
    \Iftocfeature{#2}{numbered}{\setuptoc{#3}{numbered}}{}%
    \Iftocfeature{#2}{onecolumn}{\setuptoc{#3}{leveldownonecolumn}}{}%  
    \Iftocfeature{#2}{totoc}{\setuptoc{#3}{totoc}}{}%
  }%
}
\@onlypreamble\TOCClone
%</body>
%    \end{macrocode}
% \end{command}
%
%    \begin{macrocode}
%</package>
%    \end{macrocode}
%
% \Finale
% \PrintChanges
%
% \endinput
% Local Variables:
% mode: doctex
% ispell-local-dictionary: "en_US"
% eval: (flyspell-mode 1)
% TeX-master: t
% TeX-engine: luatex-dev
% eval: (setcar (or (cl-member "Index" (setq-local TeX-command-list (copy-alist TeX-command-list)) :key #'car :test #'string-equal) (setq-local TeX-command-list (cons nil TeX-command-list))) '("Index" "mkindex %s" TeX-run-index nil t :help "makeindex for dtx"))
% End:
