xref: /netbsd-src/external/gpl3/gcc/dist/libstdc++-v3/doc/xml/manual/documentation_hacking.xml (revision a3e9eb183fc82afd2c22c9f48bcba8e00d943a4f)
1<section xmlns="http://docbook.org/ns/docbook" version="5.0"
2	 xml:id="appendix.porting.doc" xreflabel="Documentation Hacking">
3<?dbhtml filename="documentation_hacking.html"?>
4
5<info><title>Writing and Generating Documentation</title>
6  <keywordset>
7    <keyword>ISO C++</keyword>
8    <keyword>documentation</keyword>
9    <keyword>style</keyword>
10    <keyword>docbook</keyword>
11    <keyword>doxygen</keyword>
12  </keywordset>
13</info>
14
15  <section xml:id="doc.intro">
16    <info>
17    <title>Introduction</title>
18    </info>
19    <para>
20      Documentation for the GNU C++ Library is created from three
21      independent sources: a manual, a FAQ, and an API reference.
22    </para>
23    <para>
24      The sub-directory <filename class="directory">doc</filename>
25      within the main source directory contains
26      <filename>Makefile.am</filename> and
27      <filename>Makefile.in</filename>, which provide rules for
28      generating documentation, described in excruciating detail
29      below. The <filename class="directory">doc</filename>
30      sub-directory also contains three directories: <filename
31      class="directory">doxygen</filename>, which contains scripts and
32      fragments for <command>doxygen</command>, <filename
33      class="directory">html</filename>, which contains an html
34      version of the manual, and <filename
35      class="directory">xml</filename>, which contains an xml version
36      of the manual.
37    </para>
38    <para>
39      Diverging from established documentation conventions in the rest
40      of the GCC project, libstdc++ does not use Texinfo as a markup
41      language. Instead, Docbook is used to create the manual and the
42      FAQ, and Doxygen is used to construct the API
43      reference. Although divergent, this conforms to the GNU Project
44      recommendations as long as the output is of sufficient quality,
45      as per
46      <link xmlns:xlink="http://www.w3.org/1999/xlink"
47      xlink:href="http://www.gnu.org/prep/standards/standards.html#Documentation">
48      GNU Manuals</link>.
49    </para>
50  </section>
51
52  <section xml:id="doc.generation">
53    <info>
54    <title>Generating Documentation</title>
55    </info>
56
57    <para>
58      Certain Makefile rules are required by the GNU Coding
59      Standards. These standard rules generate HTML, PDF, XML, or man
60      files. For each of the generative rules, there is an additional
61      install rule that is used to install any generated documentation
62      files into the prescribed installation directory. Files are
63      installed into <filename class="directory">share/doc</filename>
64      or <filename class="directory">share/man</filename> directories.
65    </para>
66
67    <para>
68      The standard Makefile rules are conditionally supported, based
69      on the results of examining the host environment for
70      prerequisites at configuration time. If requirements are not
71      found, the rule is aliased to a dummy rule that does nothing,
72      and produces no documentation. If the requirements are found,
73      the rule forwards to a private rule that produces the requested
74      documentation.
75    </para>
76
77    <para>
78      For more details on what prerequisites were found and where,
79      please consult the file <filename>config.log</filename> in the
80      libstdc++ build directory. Compare this log to what is expected
81      for the relevant Makefile conditionals:
82      <literal>BUILD_INFO</literal>, <literal>BUILD_XML</literal>,
83      <literal>BUILD_HTML</literal>, <literal>BUILD_MAN</literal>,
84      <literal>BUILD_PDF</literal>, and <literal>BUILD_EPUB</literal>.
85    </para>
86
87    <para>
88      Supported Makefile rules:
89    </para>
90
91    <variablelist>
92      <varlistentry>
93	<term>
94	  <emphasis>make html</emphasis>
95	</term>
96	<term>
97	  <emphasis>make install-html</emphasis>
98	</term>
99	<listitem>
100	  <para>
101	    Generates multi-page HTML documentation, and installs it
102	    in the following directories:
103	  </para>
104	  <para>
105	    <filename>doc/libstdc++/libstdc++-api.html</filename>
106	  </para>
107	  <para>
108	    <filename>doc/libstdc++/libstdc++-manual.html</filename>
109	  </para>
110	</listitem>
111      </varlistentry>
112
113      <varlistentry>
114	<term>
115	  <emphasis>make pdf</emphasis>
116	</term>
117	<term>
118	  <emphasis>make install-pdf</emphasis>
119	</term>
120	<listitem>
121	  <para>
122	    Generates indexed PDF documentation, and installs it as
123	    the following files:
124	  </para>
125	  <para>
126	    <filename>doc/libstdc++/libstdc++-api.pdf</filename>
127	  </para>
128	  <para>
129	    <filename>doc/libstdc++/libstdc++-manual.pdf</filename>
130	  </para>
131	</listitem>
132      </varlistentry>
133
134      <varlistentry>
135	<term>
136	  <emphasis>make man</emphasis>
137	</term>
138	<term>
139	  <emphasis>make install-man</emphasis>
140	</term>
141	<listitem>
142	  <para>
143	    Generates man pages, and installs it in the following directory:
144	  </para>
145	  <para>
146	    <filename class="directory">man/man3/</filename>
147	  </para>
148	  <para>
149	    The generated man pages are namespace-qualified, so to look at
150	    the man page for <classname>vector</classname>, one would use
151	    <command>man std::vector</command>.
152	  </para>
153	</listitem>
154      </varlistentry>
155
156      <varlistentry>
157	<term>
158	  <emphasis>make epub</emphasis>
159	</term>
160	<term>
161	  <emphasis>make install-epub</emphasis>
162	</term>
163	<listitem>
164	  <para>
165	    Generates documentation in the ebook/portable electronic
166	    reader format called Epub, and installs it as the
167	    following file.
168	  </para>
169	  <para>
170	    <filename>doc/libstdc++/libstdc++-manual.epub</filename>
171	  </para>
172	</listitem>
173      </varlistentry>
174
175      <varlistentry>
176	<term>
177	  <emphasis>make xml</emphasis>
178	</term>
179	<term>
180	  <emphasis>make install-xml</emphasis>
181	</term>
182	<listitem>
183	  <para>
184	    Generates single-file XML documentation, and installs it
185	    as the following files:
186	  </para>
187	  <para>
188	    <filename>doc/libstdc++/libstdc++-api-single.xml</filename>
189	  </para>
190	  <para>
191	    <filename>doc/libstdc++/libstdc++-manual-single.xml</filename>
192	  </para>
193	</listitem>
194      </varlistentry>
195    </variablelist>
196
197    <para>
198      Makefile rules for several other formats are explicitly not
199      supported, and are always aliased to dummy rules. These
200      unsupported formats are: <emphasis>info</emphasis>,
201      <emphasis>ps</emphasis>, and <emphasis>dvi</emphasis>.
202    </para>
203  </section>
204
205  <section xml:id="doc.doxygen"><info><title>Doxygen</title></info>
206
207    <section xml:id="doxygen.prereq"><info><title>Prerequisites</title></info>
208
209 <table frame="all" xml:id="table.doxygen_prereq">
210<title>Doxygen Prerequisites</title>
211
212<tgroup cols="3" align="center" colsep="1" rowsep="1">
213<colspec colname="c1"/>
214<colspec colname="c2"/>
215<colspec colname="c3"/>
216
217  <thead>
218    <row>
219      <entry>Tool</entry>
220      <entry>Version</entry>
221      <entry>Required By</entry>
222    </row>
223  </thead>
224
225  <tbody>
226
227    <row>
228      <entry>coreutils</entry>
229      <entry>8.5</entry>
230      <entry>all</entry>
231    </row>
232
233    <row>
234      <entry>bash</entry>
235      <entry>4.1</entry>
236      <entry>all</entry>
237    </row>
238
239    <row>
240      <entry>doxygen</entry>
241      <entry>1.7.6.1</entry>
242      <entry>all</entry>
243    </row>
244
245    <row>
246      <entry>graphviz</entry>
247      <entry>2.26</entry>
248      <entry>graphical hierarchies</entry>
249    </row>
250
251    <row>
252      <entry>pdflatex</entry>
253      <entry>2007-59</entry>
254      <entry>pdf output</entry>
255    </row>
256
257  </tbody>
258</tgroup>
259</table>
260
261
262      <para>
263	Prerequisite tools are Bash 2.0 or later,
264	<link xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="http://www.doxygen.org">Doxygen</link>, and
265	the <link xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="http://www.gnu.org/software/coreutils/">GNU
266	coreutils</link>. (GNU versions of find, xargs, and possibly
267	sed and grep are used, just because the GNU versions make
268	things very easy.)
269      </para>
270
271      <para>
272	To generate the pretty pictures and hierarchy
273	graphs, the
274	<link xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="http://www.graphviz.org">Graphviz</link> package
275	will need to be installed. For PDF
276	output, <link xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="http://www.tug.org/applications/pdftex/">
277	pdflatex</link> is required as well as a number of TeX packages
278	such as <package>texlive-xtab</package> and
279	<package>texlive-tocloft</package>.
280      </para>
281
282      <para>
283	Be warned the PDF file generated via doxygen is extremely
284	large. At last count, the PDF file is over three thousand
285	pages. Generating this document taxes the underlying TeX
286	formatting system, and will require the expansion of TeX's memory
287	capacity. Specifically, the <literal>pool_size</literal>
288	variable in the configuration file <filename>texmf.cnf</filename> may
289	need to be increased by a minimum factor of two.
290      </para>
291    </section>
292
293    <section xml:id="doxygen.rules"><info><title>Generating the Doxygen Files</title></info>
294
295      <para>
296	The following Makefile rules run Doxygen to generate HTML
297	docs, XML docs, XML docs as a single file, PDF docs, and the
298	man pages. These rules are not conditional! If the required
299	tools are not found, or are the wrong versions, the rule may
300	end in an error.
301      </para>
302
303      <para>
304      <screen><userinput>make doc-html-doxygen</userinput></screen>
305      </para>
306
307      <para>
308      <screen><userinput>make doc-xml-doxygen</userinput></screen>
309      </para>
310
311      <para>
312      <screen><userinput>make doc-xml-single-doxygen</userinput></screen>
313      </para>
314
315      <para>
316      <screen><userinput>make doc-pdf-doxygen</userinput></screen>
317      </para>
318
319      <para>
320      <screen><userinput>make doc-man-doxygen</userinput></screen>
321      </para>
322
323      <para>
324	Generated files are output into separate sub directories of
325	<filename class="directory">doc/doxygen/</filename> in the
326	build directory, based on the output format. For instance, the
327	HTML docs will be in <filename class="directory">doc/doxygen/html</filename>.
328      </para>
329
330      <para>
331	Careful observers will see that the Makefile rules simply call
332	a script from the source tree, <filename>run_doxygen</filename>, which
333	does the actual work of running Doxygen and then (most
334	importantly) massaging the output files. If for some reason
335	you prefer to not go through the Makefile, you can call this
336	script directly. (Start by passing <literal>--help</literal>.)
337      </para>
338
339      <para>
340	If you wish to tweak the Doxygen settings, do so by editing
341	<filename>doc/doxygen/user.cfg.in</filename>. Notes to fellow
342	library hackers are written in triple-# comments.
343      </para>
344
345    </section>
346
347 <section xml:id="doxygen.debug">
348   <info><title>Debugging Generation</title></info>
349
350	<para>
351	  Sometimes, mis-configuration of the pre-requisite tools can
352	  lead to errors when attempting to build the
353	  documentation. Here are some of the obvious errors, and ways
354	  to fix some common issues that may appear quite cryptic.
355	</para>
356
357	<para>
358	  First, if using a rule like <code>make pdf</code>, try to
359	  narrow down the scope of the error to either docbook
360	  (<code>make doc-pdf-docbook</code>) or doxygen (<code>make
361	  doc-pdf-doxygen</code>).
362	</para>
363	<para>
364	  Working on the doxygen path only, closely examine the
365	  contents of the following build directory: <filename
366	  class="directory">build/target/libstdc++-v3/doc/doxygen/latex</filename>.
367	  Pay attention to three files enclosed within, annotated as follows.
368	</para>
369<itemizedlist>
370
371<listitem>
372  <para>
373   <emphasis>refman.tex</emphasis>
374  </para>
375
376  <para>
377    The actual latex file, or partial latex file. This is generated
378    via <command>doxygen</command>, and is the LaTeX version of the
379    Doxygen XML file <filename>libstdc++-api.xml</filename>. Go to a specific
380    line, and look at the generated LaTeX, and try to deduce what
381    markup in <filename>libstdc++-api.xml</filename> is causing it.
382  </para>
383</listitem>
384
385<listitem>
386  <para>
387   <emphasis>refman.log</emphasis>
388  </para>
389
390  <para>
391    A log created by <command>latex</command> as it processes the
392    <filename>refman.tex</filename> file. If generating the PDF fails
393    look at the end of this file for errors such as:
394    <screen>
395    ! LaTeX Error: File `xtab.sty' not found.
396    </screen>
397    This indicates a required TeX package is missing. For the example
398    above the <package>texlive-xtab</package> package needs to be
399    installed.
400  </para>
401</listitem>
402
403<listitem>
404  <para>
405   <emphasis>refman.out</emphasis>
406  </para>
407
408  <para>
409    A log of the compilation of the converted LaTeX form to PDF. This
410    is a linear list, from the beginning of the
411    <filename>refman.tex</filename> file: the last entry of this file
412    should be the end of the LaTeX file. If it is truncated, then you
413    know that the last entry is the last part of the generated LaTeX
414    source file that is valid. Often this file contains an error with
415    a specific line number of <filename>refman.tex</filename> that is
416    incorrect, or will have clues at the end of the file with the dump
417    of the memory usage of LaTeX.
418  </para>
419</listitem>
420</itemizedlist>
421
422	<para>
423	  If the error at hand is not obvious after examination, a
424	  fall-back strategy is to start commenting out the doxygen
425	  input sources, which can be found in
426	  <filename>doc/doxygen/user.cfg.in</filename>, look for the
427	  <literal>INPUT</literal> tag. Start by commenting out whole
428	  directories of header files, until the offending header is
429	  identified. Then, read the latex log files to try and find
430	  surround text, and look for that in the offending header.
431	</para>
432
433 </section>
434
435    <section xml:id="doxygen.markup"><info><title>Markup</title></info>
436
437
438      <para>
439	In general, libstdc++ files should be formatted according to
440	the rules found in the
441	<link linkend="contrib.coding_style">Coding Standard</link>. Before
442	any doxygen-specific formatting tweaks are made, please try to
443	make sure that the initial formatting is sound.
444      </para>
445
446      <para>
447	Adding Doxygen markup to a file (informally called
448	<quote>doxygenating</quote>) is very simple. The Doxygen manual can be
449	found
450	<link xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="http://www.stack.nl/~dimitri/doxygen/download.html#latestman">here</link>.
451	We try to use a very-recent version of Doxygen.
452      </para>
453
454      <para>
455	For classes, use
456	<classname>deque</classname>/<classname>vector</classname>/<classname>list</classname>
457	and <classname>std::pair</classname> as examples.  For
458	functions, see their member functions, and the free functions
459	in <filename class="headerfile">stl_algobase.h</filename>. Member
460	functions of other container-like types should read similarly to
461	these member functions.
462      </para>
463
464      <para>
465	Some commentary to accompany
466	the first list in the <link xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="http://www.stack.nl/~dimitri/doxygen/manual/docblocks.html">Special
467	Documentation Blocks</link> section of the Doxygen manual:
468      </para>
469
470      <orderedlist inheritnum="ignore" continuation="restarts">
471	<listitem>
472	  <para>For longer comments, use the Javadoc style...</para>
473	</listitem>
474
475	<listitem>
476	  <para>
477	    ...not the Qt style. The intermediate *'s are preferred.
478	  </para>
479	</listitem>
480
481 	<listitem>
482	  <para>
483	    Use the triple-slash style only for one-line comments (the
484	    <quote>brief</quote> mode).
485	  </para>
486	</listitem>
487
488	<listitem>
489	  <para>
490	    This is disgusting. Don't do this.
491	  </para>
492	</listitem>
493      </orderedlist>
494
495      <para>
496	Some specific guidelines:
497      </para>
498
499      <para>
500	Use the @-style of commands, not the !-style. Please be
501	careful about whitespace in your markup comments. Most of the
502	time it doesn't matter; doxygen absorbs most whitespace, and
503	both HTML and *roff are agnostic about whitespace. However,
504	in &lt;pre&gt; blocks and @code/@endcode sections, spacing can
505	have <quote>interesting</quote> effects.
506      </para>
507
508      <para>
509	Use either kind of grouping, as
510	appropriate. <filename>doxygroups.cc</filename> exists for this
511	purpose. See <filename class="headerfile">stl_iterator.h</filename>
512	for a good example of the <quote>other</quote> kind of grouping.
513      </para>
514
515      <para>
516	Please use markup tags like @p and @a when referring to things
517	such as the names of function parameters. Use @e for emphasis
518	when necessary. Use @c to refer to other standard names.
519	(Examples of all these abound in the present code.)
520      </para>
521
522      <para>
523	Complicated math functions should use the multi-line format.
524	An example from <filename class="headerfile">random.h</filename>:
525      </para>
526
527      <para>
528<literallayout class="normal">
529/**
530 * @brief A model of a linear congruential random number generator.
531 *
532 * @f[
533 *     x_{i+1}\leftarrow(ax_{i} + c) \bmod m
534 * @f]
535 */
536</literallayout>
537      </para>
538
539      <para>
540	One area of note is the markup required for
541	<literal>@file</literal> markup in header files. Two details
542	are important: for filenames that have the same name in
543	multiple directories, include part of the installed path to
544	disambiguate. For example:
545      </para>
546
547      <para>
548<literallayout class="normal">
549/** @file debug/vector
550 *  This file is a GNU debug extension to the Standard C++ Library.
551 */
552</literallayout>
553      </para>
554
555      <para>
556	The other relevant detail for header files is the use of a
557	libstdc++-specific doxygen alias that helps distinguish
558	between public header files (like <filename class="headerfile">random</filename>)
559	from implementation or private header files (like
560	<filename class="headerfile">bits/c++config.h</filename>.) This alias is spelled
561	<literal>@headername</literal> and can take one or two
562	arguments that detail the public header file or files that
563	should be included to use the contents of the file. All header
564	files that are not intended for direct inclusion must use
565	<literal>headername</literal> in the <literal>file</literal>
566	block. An example:
567      </para>
568
569      <para>
570<literallayout class="normal">
571/** @file bits/basic_string.h
572 *  This is an internal header file, included by other library headers.
573 *  Do not attempt to use it directly. @headername{string}
574 */
575</literallayout>
576      </para>
577
578      <para>
579	Be careful about using certain, special characters when
580	writing Doxygen comments. Single and double quotes, and
581	separators in filenames are two common trouble spots. When in
582	doubt, consult the following table.
583      </para>
584
585<table frame="all" xml:id="table.doxygen_cmp">
586<title>HTML to Doxygen Markup Comparison</title>
587
588<tgroup cols="2" align="left" colsep="1" rowsep="1">
589<colspec colname="c1"/>
590<colspec colname="c2"/>
591
592  <thead>
593    <row>
594      <entry>HTML</entry>
595      <entry>Doxygen</entry>
596    </row>
597  </thead>
598
599  <tbody>
600    <row>
601      <entry>\</entry>
602      <entry>\\</entry>
603    </row>
604
605    <row>
606      <entry>"</entry>
607      <entry>\"</entry>
608    </row>
609
610    <row>
611      <entry>'</entry>
612      <entry>\'</entry>
613    </row>
614
615    <row>
616      <entry>&lt;i&gt;</entry>
617      <entry>@a word</entry>
618    </row>
619
620    <row>
621      <entry>&lt;b&gt;</entry>
622      <entry>@b word</entry>
623    </row>
624
625    <row>
626      <entry>&lt;code&gt;</entry>
627      <entry>@c word</entry>
628    </row>
629
630    <row>
631      <entry>&lt;em&gt;</entry>
632      <entry>@a word</entry>
633    </row>
634
635    <row>
636      <entry>&lt;em&gt;</entry>
637      <entry>&lt;em&gt;two words or more&lt;/em&gt;</entry>
638    </row>
639  </tbody>
640
641</tgroup>
642</table>
643
644
645    </section>
646
647  </section>
648
649  <section xml:id="doc.docbook"><info><title>Docbook</title></info>
650
651
652    <section xml:id="docbook.prereq"><info><title>Prerequisites</title></info>
653
654
655 <table frame="all" xml:id="table.docbook_prereq">
656<title>Docbook Prerequisites</title>
657
658<tgroup cols="3" align="center" colsep="1" rowsep="1">
659<colspec colname="c1"/>
660<colspec colname="c2"/>
661<colspec colname="c3"/>
662
663  <thead>
664    <row>
665      <entry>Tool</entry>
666      <entry>Version</entry>
667      <entry>Required By</entry>
668    </row>
669  </thead>
670
671  <tbody>
672
673    <row>
674      <entry>docbook5-style-xsl</entry>
675      <entry>1.76.1</entry>
676      <entry>all</entry>
677    </row>
678
679    <row>
680      <entry>xsltproc</entry>
681      <entry>1.1.26</entry>
682      <entry>all</entry>
683    </row>
684
685    <row>
686      <entry>xmllint</entry>
687      <entry>2.7.7</entry>
688      <entry>validation</entry>
689    </row>
690
691    <row>
692      <entry>dblatex</entry>
693      <entry>0.3</entry>
694      <entry>pdf output</entry>
695    </row>
696
697    <row>
698      <entry>pdflatex</entry>
699      <entry>2007-59</entry>
700      <entry>pdf output</entry>
701    </row>
702
703    <row>
704      <entry>docbook2X</entry>
705      <entry>0.8.8</entry>
706      <entry>info output</entry>
707    </row>
708
709    <row>
710      <entry>epub3 stylesheets</entry>
711      <entry>b3</entry>
712      <entry>epub output</entry>
713    </row>
714
715  </tbody>
716</tgroup>
717</table>
718
719      <para>
720	Editing the DocBook sources requires an XML editor. Many
721	exist: some notable options
722	include <command>emacs</command>, <application>Kate</application>,
723	or <application>Conglomerate</application>.
724      </para>
725
726      <para>
727	Some editors support special <quote>XML Validation</quote>
728	modes that can validate the file as it is
729	produced. Recommended is the <command>nXML Mode</command>
730	for <command>emacs</command>.
731      </para>
732
733      <para>
734	Besides an editor, additional DocBook files and XML tools are
735	also required.
736      </para>
737
738      <para>
739	Access to the DocBook 5.0 stylesheets and schema is required. The
740	stylesheets are usually packaged by vendor, in something
741	like <filename>docbook5-style-xsl</filename>. To exactly match
742	generated output, please use a version of the stylesheets
743	equivalent
744	to <filename>docbook5-style-xsl-1.75.2-3</filename>. The
745	installation directory for this package corresponds to
746	the <literal>XSL_STYLE_DIR</literal>
747	in <filename>doc/Makefile.am</filename> and defaults
748	to <filename class="directory">/usr/share/sgml/docbook/xsl-ns-stylesheets</filename>.
749      </para>
750
751      <para>
752	For processing XML, an XSLT processor and some style
753	sheets are necessary. Defaults are <command>xsltproc</command>
754	provided by <filename>libxslt</filename>.
755      </para>
756
757      <para>
758	For validating the XML document, you'll need
759	something like <command>xmllint</command> and access to the
760	relevant DocBook schema. These are provided
761	by a vendor package like <filename>libxml2</filename> and <filename>docbook5-schemas-5.0-4</filename>
762      </para>
763
764      <para>
765	For PDF output, something that transforms valid Docbook XML to PDF is
766	required. Possible solutions include <link xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="http://dblatex.sourceforge.net">dblatex</link>,
767	<command>xmlto</command>, or <command>prince</command>. Of
768	these, <command>dblatex</command> is the default.
769	Please consult the <email>libstdc++@gcc.gnu.org</email> list when
770	preparing printed manuals for current best practice and
771	suggestions.
772      </para>
773
774      <para>
775	For Texinfo output, something that transforms valid Docbook
776	XML to Texinfo is required. The default choice is <link xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="http://docbook2x.sourceforge.net/">docbook2X</link>.
777      </para>
778
779      <para>
780	For epub output, the <link xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="https://sourceforge.net/projects/docbook/files/epub3/">stylesheets</link> for EPUB3 are required. These stylesheets are still in development. To validate the created file, <link xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="https://github.com/IDPF/epubcheck">epubcheck</link> is necessary.
781      </para>
782    </section>
783
784    <section xml:id="docbook.rules"><info><title>Generating the DocBook Files</title></info>
785
786
787      <para>
788	The following Makefile rules generate (in order): an HTML
789	version of all the DocBook documentation, a PDF version of the
790	same, and a single XML document.  These rules are not
791	conditional! If the required tools are not found, or are the
792	wrong versions, the rule may end in an error.
793      </para>
794
795      <para>
796      <screen><userinput>make doc-html-docbook</userinput></screen>
797      </para>
798
799      <para>
800      <screen><userinput>make doc-pdf-docbook</userinput></screen>
801      </para>
802
803      <para>
804      <screen><userinput>make doc-xml-single-docbook</userinput></screen>
805      </para>
806
807      <para>
808	Generated files are output into separate sub-directores of
809	<filename class="directory">doc/docbook/</filename> in the
810	build directory, based on the output format. For instance, the
811	HTML docs will be in <filename
812	class="directory">doc/docbook/html</filename>.
813      </para>
814
815      <para>
816	The <screen>doc-html-docbook-regenerate</screen> target will generate
817	the HTML files and copy them back to the libstdc++ source tree.
818	This can be used to update the HTML files that are checked in to
819	version control.
820      </para>
821
822      <para>
823	If the Docbook stylesheets are installed in a custom location,
824	one can use the variable <literal>XSL_STYLE_DIR</literal> to
825	override the Makefile defaults. For example:
826      </para>
827
828      <screen>
829	<userinput>
830make <literal>XSL_STYLE_DIR="/usr/share/xml/docbook/stylesheet/nwalsh"</literal> doc-html-docbook
831	</userinput>
832      </screen>
833
834      </section>
835
836    <section xml:id="docbook.debug">
837	<info><title>Debugging Generation</title></info>
838
839	<para>
840	  Sometimes, mis-configuration of the pre-requisite tools can
841	  lead to errors when attempting to build the
842	  documentation. Here are some of the obvious errors, and ways
843	  to fix some common issues that may appear quite cryptic.
844	</para>
845
846	<para>
847	  First, if using a rule like <code>make pdf</code>, try to
848	  narrow down the scope of the error to either docbook
849	  (<code>make doc-pdf-docbook</code>) or doxygen (<code>make
850	  doc-pdf-doxygen</code>).
851	</para>
852
853	<para>
854	  Working on the docbook path only, closely examine the
855	  contents of the following build directory:
856	  <filename class="directory">build/target/libstdc++-v3/doc/docbook/latex</filename>.
857	  Pay attention to three files enclosed within, annotated as follows.
858	</para>
859
860<itemizedlist>
861
862<listitem>
863  <para>
864   <emphasis>spine.tex</emphasis>
865  </para>
866
867  <para>
868    The actual latex file, or partial latex file. This is generated
869    via <command>dblatex</command>, and is the LaTeX version of the
870    DocBook XML file <filename>spine.xml</filename>. Go to a specific
871    line, and look at the generated LaTeX, and try to deduce what
872    markup in <filename>spine.xml</filename> is causing it.
873  </para>
874</listitem>
875
876<listitem>
877  <para>
878   <emphasis>spine.out</emphasis>
879  </para>
880
881  <para>
882    A log of the conversion from the XML form to the LaTeX form. This
883    is a linear list, from the beginning of the
884    <filename>spine.xml</filename> file: the last entry of this file
885    should be the end of the DocBook file. If it is truncated, then
886    you know that the last entry is the last part of the XML source
887    file that is valid. The error is after this point.
888  </para>
889</listitem>
890
891
892<listitem>
893  <para>
894   <emphasis>spine.log</emphasis>
895  </para>
896
897  <para>
898    A log of the compilation of the converted LaTeX form to pdf. This
899    is a linear list, from the beginning of the
900    <filename>spine.tex</filename> file: the last entry of this file
901    should be the end of the LaTeX file. If it is truncated, then you
902    know that the last entry is the last part of the generated LaTeX
903    source file that is valid. Often this file contains an error with
904    a specific line number of <filename>spine.tex</filename> that is
905    incorrect.
906  </para>
907</listitem>
908
909</itemizedlist>
910
911	<para>
912	  If the error at hand is not obvious after examination, or if one
913	  encounters the inscruitable <quote>Incomplete
914	  \ifmmode</quote> error, a fall-back strategy is to start
915	  commenting out parts of the XML document (regardless of what
916	  this does to over-all document validity). Start by
917	  commenting out each of the largest parts of the
918	  <filename>spine.xml</filename> file, section by section,
919	  until the offending section is identified.
920	</para>
921
922
923    </section>
924
925    <section xml:id="docbook.validation"><info><title>Editing and Validation</title></info>
926
927      <para>
928	After editing the xml sources, please make sure that the XML
929	documentation and markup is still valid. This can be
930	done easily, with the following validation rule:
931      </para>
932
933      <screen>
934	<userinput>make doc-xml-validate-docbook</userinput>
935      </screen>
936
937      <para>
938	This is equivalent to doing:
939      </para>
940
941      <screen>
942	<userinput>
943	  xmllint --noout --valid <filename>xml/index.xml</filename>
944	</userinput>
945      </screen>
946
947      <para>
948	Please note that individual sections and chapters of the
949	manual can be validated by substituting the file desired for
950	<filename>xml/index.xml</filename> in the command
951	above. Reducing scope in this manner can be helpful when
952	validation on the entire manual fails.
953      </para>
954
955      <para>
956	All Docbook xml sources should always validate. No excuses!
957      </para>
958
959    </section>
960
961    <section xml:id="docbook.examples"><info><title>File Organization and Basics</title></info>
962
963
964    <literallayout class="normal">
965      <emphasis>Which files are important</emphasis>
966
967      All Docbook files are in the directory
968      libstdc++-v3/doc/xml
969
970      Inside this directory, the files of importance:
971      spine.xml	 	- index to documentation set
972      manual/spine.xml  - index to manual
973      manual/*.xml  	- individual chapters and sections of the manual
974      faq.xml  		- index to FAQ
975      api.xml  		- index to source level / API
976
977      All *.txml files are template xml files, i.e., otherwise empty files with
978      the correct structure, suitable for filling in with new information.
979
980      <emphasis>Canonical Writing Style</emphasis>
981
982      class template
983      function template
984      member function template
985      (via C++ Templates, Vandevoorde)
986
987      class in namespace std: allocator, not std::allocator
988
989      header file: iostream, not &lt;iostream&gt;
990
991
992      <emphasis>General structure</emphasis>
993
994      &lt;set&gt;
995      &lt;book&gt;
996      &lt;/book&gt;
997
998      &lt;book&gt;
999      &lt;chapter&gt;
1000      &lt;/chapter&gt;
1001      &lt;/book&gt;
1002
1003      &lt;book&gt;
1004      &lt;part&gt;
1005      &lt;chapter&gt;
1006      &lt;section&gt;
1007      &lt;/section&gt;
1008
1009      &lt;sect1&gt;
1010      &lt;/sect1&gt;
1011
1012      &lt;sect1&gt;
1013      &lt;sect2&gt;
1014      &lt;/sect2&gt;
1015      &lt;/sect1&gt;
1016      &lt;/chapter&gt;
1017
1018      &lt;chapter&gt;
1019      &lt;/chapter&gt;
1020      &lt;/part&gt;
1021      &lt;/book&gt;
1022
1023      &lt;/set&gt;
1024    </literallayout>
1025    </section>
1026
1027    <section xml:id="docbook.markup"><info><title>Markup By Example</title></info>
1028
1029
1030      <para>
1031	Complete details on Docbook markup can be found in the
1032	<link xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="https://tdg.docbook.org/tdg/5.0/ref-elements.html">DocBook Element Reference</link>.
1033	An incomplete reference for HTML to Docbook conversion is
1034	detailed in the table below.
1035      </para>
1036
1037<table frame="all" xml:id="table.docbook_cmp">
1038<title>HTML to Docbook XML Markup Comparison</title>
1039
1040<tgroup cols="2" align="left" colsep="1" rowsep="1">
1041<colspec colname="c1"/>
1042<colspec colname="c2"/>
1043
1044  <thead>
1045    <row>
1046      <entry>HTML</entry>
1047      <entry>Docbook</entry>
1048    </row>
1049  </thead>
1050
1051  <tbody>
1052    <row>
1053      <entry>&lt;p&gt;</entry>
1054      <entry>&lt;para&gt;</entry>
1055    </row>
1056    <row>
1057      <entry>&lt;pre&gt;</entry>
1058      <entry>&lt;computeroutput&gt;, &lt;programlisting&gt;,
1059	&lt;literallayout&gt;</entry>
1060    </row>
1061    <row>
1062      <entry>&lt;ul&gt;</entry>
1063      <entry>&lt;itemizedlist&gt;</entry>
1064    </row>
1065    <row>
1066      <entry>&lt;ol&gt;</entry>
1067      <entry>&lt;orderedlist&gt;</entry>
1068    </row>
1069    <row>
1070      <entry>&lt;il&gt;</entry>
1071      <entry>&lt;listitem&gt;</entry>
1072    </row>
1073    <row>
1074      <entry>&lt;dl&gt;</entry>
1075      <entry>&lt;variablelist&gt;</entry>
1076    </row>
1077    <row>
1078      <entry>&lt;dt&gt;</entry>
1079      <entry>&lt;term&gt;</entry>
1080    </row>
1081    <row>
1082      <entry>&lt;dd&gt;</entry>
1083      <entry>&lt;listitem&gt;</entry>
1084    </row>
1085
1086    <row>
1087      <entry>&lt;a href=""&gt;</entry>
1088      <entry>&lt;ulink url=""&gt;</entry>
1089    </row>
1090    <row>
1091      <entry>&lt;code&gt;</entry>
1092      <entry>&lt;literal&gt;, &lt;programlisting&gt;</entry>
1093    </row>
1094    <row>
1095      <entry>&lt;strong&gt;</entry>
1096      <entry>&lt;emphasis&gt;</entry>
1097    </row>
1098    <row>
1099      <entry>&lt;em&gt;</entry>
1100      <entry>&lt;emphasis&gt;</entry>
1101    </row>
1102    <row>
1103      <entry>"</entry>
1104      <entry>&lt;quote&gt;</entry>
1105    </row>
1106   </tbody>
1107</tgroup>
1108</table>
1109
1110<para>
1111  And examples of detailed markup for which there are no real HTML
1112  equivalents are listed in the table below.
1113</para>
1114
1115<table frame="all" xml:id="table.docbook_elem">
1116<title>Docbook XML Element Use</title>
1117
1118<tgroup cols="2" align="left" colsep="1" rowsep="1">
1119<colspec colname="c1"/>
1120<colspec colname="c2"/>
1121
1122  <thead>
1123    <row>
1124      <entry>Element</entry>
1125      <entry>Use</entry>
1126    </row>
1127  </thead>
1128
1129  <tbody>
1130    <row>
1131      <entry>&lt;structname&gt;</entry>
1132      <entry>&lt;structname&gt;char_traits&lt;/structname&gt;</entry>
1133    </row>
1134    <row>
1135      <entry>&lt;classname&gt;</entry>
1136      <entry>&lt;classname&gt;string&lt;/classname&gt;</entry>
1137    </row>
1138    <row>
1139      <entry>&lt;function&gt;</entry>
1140      <entry>
1141	<para>&lt;function&gt;clear()&lt;/function&gt;</para>
1142	<para>&lt;function&gt;fs.clear()&lt;/function&gt;</para>
1143      </entry>
1144    </row>
1145    <row>
1146      <entry>&lt;type&gt;</entry>
1147      <entry>&lt;type&gt;long long&lt;/type&gt;</entry>
1148    </row>
1149    <row>
1150      <entry>&lt;varname&gt;</entry>
1151      <entry>&lt;varname&gt;fs&lt;/varname&gt;</entry>
1152    </row>
1153    <row>
1154      <entry>&lt;literal&gt;</entry>
1155      <entry>
1156	<para>&lt;literal&gt;-Weffc++&lt;/literal&gt;</para>
1157	<para>&lt;literal&gt;rel_ops&lt;/literal&gt;</para>
1158      </entry>
1159    </row>
1160    <row>
1161      <entry>&lt;constant&gt;</entry>
1162      <entry>
1163	<para>&lt;constant&gt;_GNU_SOURCE&lt;/constant&gt;</para>
1164	<para>&lt;constant&gt;3.0&lt;/constant&gt;</para>
1165      </entry>
1166    </row>
1167    <row>
1168      <entry>&lt;command&gt;</entry>
1169      <entry>&lt;command&gt;g++&lt;/command&gt;</entry>
1170    </row>
1171    <row>
1172      <entry>&lt;errortext&gt;</entry>
1173      <entry>&lt;errortext&gt;In instantiation of&lt;/errortext&gt;</entry>
1174    </row>
1175    <row>
1176      <entry>&lt;filename&gt;</entry>
1177      <entry>
1178	<para>&lt;filename class="headerfile"&gt;ctype.h&lt;/filename&gt;</para>
1179	<para>&lt;filename class="directory"&gt;/home/gcc/build&lt;/filename&gt;</para>
1180	<para>&lt;filename class="libraryfile"&gt;libstdc++.so&lt;/filename&gt;</para>
1181      </entry>
1182    </row>
1183   </tbody>
1184</tgroup>
1185</table>
1186
1187</section>
1188</section>
1189</section>
1190