TODO

   1 ************************************************************************
   2 * Official mandoc TODO.
   3 * $Id: TODO,v 1.229 2017/01/28 22:32:51 schwarze Exp $
   4 ************************************************************************
   5
   6 Many issues are annotated for difficulty as follows:
   7
   8  - loc = locality of the issue
   9     *    single file issue, affects file only, or very few
  10     **   single module issue, affects several files of one module
  11     ***  cross-module issue, significantly impacts multiple modules
  12          and may require substantial changes to internal interfaces
  13  - exist = difficulty of the existing code in this area
  14     *    affected code is straightforward and easy to read and change
  15     **   affected code is somewhat complex, but once you understand
  16          the design, not particularly difficult to understand
  17     ***  affected code uses a special, exceptionally tricky design
  18  - algo = difficulty of the new algorithm to be written
  19     *    the required logic and code is straightforward
  20     **   the required logic is somewhat complex and needs a careful design
  21     ***  the required logic is exceptionally tricky,
  22          maybe an approach to solve that is not even known yet
  23  - size = the amount of code to be written or changed
  24     *    a small number of lines (at most 100, usually much less)
  25     **   a considerable amount of code (several dozen to a few hundred)
  26     ***  a large amount of code (many hundreds, maybe thousands)
  27  - imp = importance of the issue
  28     *    mostly for completeness
  29     **   would be nice to have
  30     ***  issue causes considerable inconvenience
  31
  32 Obviously, as the issues have not been solved yet, these annotations
  33 are mere guesses, and some may be wrong.
  34
  35 ************************************************************************
  36 * missing features
  37 ************************************************************************
  38
  39 --- missing roff features ----------------------------------------------
  40
  41 - .ad (adjust margins)
  42   .ad l -- adjust left margin only (flush left)
  43   .ad r -- adjust right margin only (flush right)
  44   .ad c -- center text on line
  45   .ad b -- adjust both margins (alias: .ad n)
  46   .na   -- temporarily disable adjustment without changing the mode
  47   .ad   -- re-enable adjustment without changing the mode
  48   Adjustment mode is ignored while in no-fill mode (.nf).
  49   loc ***  exist ***  algo **  size **  imp **  (parser reorg would help)
  50
  51 - .fc (field control)
  52   found by naddy@ in xloadimage(1)
  53   loc **  exist ***  algo *  size *  imp *
  54
  55 - .nr third argument (auto-increment step size, requires \n+)
  56   found by bentley@ in sbcl(1)  Mon, 9 Dec 2013 18:36:57 -0700
  57   loc *  exist *  algo *  size *  imp **
  58
  59 - .ns (no-space mode) occurs in xine-config(1)
  60   when implementing this, also let .TH set it
  61   reported by brad@  Sat, 15 Jan 2011 15:45:23 -0500
  62   loc ***  exist ***  algo ***  size **  imp *
  63
  64 - .ta (tab settings)
  65   #1 most important issue naddy@ Mon, 16 Feb 2015 20:59:17 +0100
  66   ircbug(1) gnats(1) reported by brad@  Sat, 15 Jan 2011 15:50:51 -0500
  67   also Tcl_NewStringObj(3) via wiz@  Wed, 5 Mar 2014 22:27:43 +0100
  68   also posix2time(3) Carsten Kunze  Mon, 1 Dec 2014 13:03:10 +0100
  69   loc **  exist ***  algo **  size **  imp ***
  70
  71 - .ti (temporary indent)
  72   found by naddy@ in xloadimage(1) [devel/libvstr] vstr(3)
  73   found by bentley@ in nmh(1)  Mon, 23 Apr 2012 13:38:28 -0600
  74   loc **  exist **  algo **  size *  imp ** (parser reorg helps a lot)
  75
  76 - .while and .shift
  77   found by jca@ in ratpoison(1)  Sun, 30 Jun 2013 12:01:09 +0200
  78   loc *  exist **  algo **  size **  imp **
  79
  80 - \h horizontal move
  81   #2 most important issue naddy@  Mon, 16 Feb 2015 20:59:17 +0100
  82   found in cclive(1) nasm(1) bogofilter(1) asciidoc/DocBook output
  83   bentley@ on discuss@  Sat, 21 Sep 2013 22:29:34 -0600
  84   naddy@  Thu, 4 Dec 2014 16:26:41 +0100
  85   loc **  exist **  algo **  size *  imp *** (parser reorg helps a lot)
  86
  87 - \n+ and \n- numerical register increment and decrement
  88   found by bentley@ in sbcl(1)  Mon, 9 Dec 2013 18:36:57 -0700
  89   loc *  exist *  algo *  size *  imp **
  90
  91 - \n(.$ macro argument count number register; ocserv(8) by autogen
  92   found by sthen@  Thu, 19 Feb 2015 22:03:01 +0000
  93   loc *  exist **  algo *  size *  imp **
  94
  95 - \w'' improve width measurements
  96   would not be very useful without an expression parser, see below
  97   needed for Tcl_NewStringObj(3) via wiz@  Wed, 5 Mar 2014 22:27:43 +0100
  98   loc **  exist ***  algo ***  size *  imp ***
  99
 100 - \\ in high-level macro arguments
 101   Currently, \\ is expanded in two situations:
 102   1) macro and string definition (roff.c setstrn())
 103   2) macro argument parsing (mandoc.c mandoc_getarg())
 104   For user defined macros, the second happens in time because of ROFF_REPARSE.
 105   But for standard high-level macros, it only happens after entering the
 106   high level parsers, which is too late because the code doesn't get
 107   back to roff.c roff_res() from that point.  Because this requires
 108   distinguishing requests, user-defined macros and standard macros
 109   on the roff_res() level, it is hard to solve without the parser reorg.
 110   Found by naddy@ in devel/cutils cobfusc(1)  Mon, 16 Feb 2015 19:10:52 +0100
 111   loc ***  exist ***  algo ***  size **  imp *
 112
 113 - using undefined strings or macros defines them to be empty
 114   wl@  Mon, 14 Nov 2011 14:37:01 +0000
 115   loc *  exist *  algo *  size *  imp *
 116
 117 --- missing mdoc features ----------------------------------------------
 118
 119 - .Bl -column .Xo support is missing
 120   ultimate goal:
 121   restore .Xr and .Dv to
 122   lib/libc/compat-43/sigvec.3
 123   lib/libc/gen/signal.3
 124   lib/libc/sys/sigaction.2
 125   loc *  exist ***  algo ***  size *  imp **
 126
 127 - edge case: decide how to deal with blk_full bad nesting, e.g.
 128   .Sh .Nm .Bk .Nm .Ek .Sh found by jmc@ in ssh-keygen(1)
 129   from jmc@  Wed, 14 Jul 2010 18:10:32 +0100
 130   loc *  exist ***  algo ***  size **  imp **
 131
 132 - .Bd -centered implies -filled, not -unfilled, which is not
 133   easy to implement; it requires code similar to .ce, which
 134   we don't have either.
 135   Besides, groff has bug causing text right *before* .Bd -centered
 136   to be centered as well.
 137   loc ***  exist ***  algo **  size **  imp **  (parser reorg would help)
 138
 139 - .Bd -filled should not be the same as .Bd -ragged, but align both
 140   the left and right margin.  In groff, it is implemented in terms
 141   of .ad b, which we don't have either.  Found in cksum(1).
 142   loc ***  exist ***  algo **  size **  imp **  (parser reorg would help)
 143
 144 - implement blank `Bl -column', such as
 145   .Bl -column
 146   .It foo Ta bar
 147   .El
 148   loc *  exist ***  algo ***  size *  imp *
 149
 150 - explicitly disallow nested `Bl -column', which would clobber internal
 151   flags defined for struct mdoc_macro
 152   loc *  exist *  algo *  size *  imp **
 153
 154 - In .Bl -column .It, the end of the line probably has to be regarded
 155   as an implicit .Ta, if there could be one, see the following mildly
 156   ugly code from login.conf(5):
 157     .Bl -column minpasswordlen program xetcxmotd
 158     .It path Ta path Ta value of Dv _PATH_DEFPATH
 159     .br
 160     Default search path.
 161   reported by Michal Mazurek <akfaew at jasminek dot net>
 162   via jmc@ Thu, 7 Apr 2011 16:00:53 +0059
 163   loc *  exist ***  algo **  size *  imp **
 164
 165 - inside `.Bl -column' phrases, punctuation is handled like normal
 166   text, e.g. `.Bl -column .It Fl x . Ta ...' should give "-x -."
 167
 168 - inside `.Bl -column' phrases, TERMP_IGNDELIM handling by `Pf'
 169   is not safe, e.g. `.Bl -column .It Pf a b .' gives "ab."
 170   but should give "ab ."
 171
 172 - check whether it is correct that `D1' uses INDENT+1;
 173   does it need its own constant?
 174   loc *  exist **  algo **  size *  imp **
 175
 176 - prohibit `Nm' from having non-text HEAD children
 177   (e.g., NetBSD mDNSShared/dns-sd.1)
 178   (mdoc_html.c and mdoc_term.c `Nm' handlers can be slightly simplified)
 179
 180 - support translated section names
 181   e.g. x11/scrotwm scrotwm_es.1:21:2: error: NAME section must be first
 182   that one uses NOMBRE because it is spanish...
 183   deraadt tends to think that section-dependent macro behaviour
 184   is a bad idea in the first place, so this may be irrelevant
 185   loc **  exist **  algo **  size *  imp **
 186
 187 - When there is free text in the SYNOPSIS and that free text contains
 188   the .Nm macro, groff somehow understands to treat the .Nm as an in-line
 189   macro, while mandoc treats it as a block macro and breaks the line.
 190   No idea how the logic for distinguishing in-line and block instances
 191   should be, needs investigation.
 192   uqs@  Thu, 2 Jun 2011 11:03:51 +0200
 193   uqs@  Thu, 2 Jun 2011 11:33:35 +0200
 194   loc *  exist **  algo ***  size *  imp **
 195
 196 --- missing tbl features -----------------------------------------------
 197
 198 - horizontal lines in the layout still consume data cells
 199   and can be mixed with actual data on the same table line
 200   synaptics(4) found by tedu@  Mon, 17 Aug 2015 21:17:42 -0400
 201   loc **  exist **  algo **  size **  imp ***
 202
 203 - break long text into lines inside cells
 204   net/lftp(1) from jirib via bentley@ Sep 13, 2016
 205
 206 - layout l1 for a column of max text width 3 reduces the following
 207   inter-column spacing for groff, but not for mandoc
 208   net/lftp(1) from jirib via bentley@ Sep 13, 2016
 209
 210 - the "w" layout option is ignored
 211   synaptics(4) found by tedu@  Mon, 17 Aug 2015 21:17:42 -0400
 212   loc *  exist *  algo *  size *  imp **
 213
 214 - the "s" layout column specifier is used for placement of data
 215   into columns, but ignored during column width calculations
 216   synaptics(4) found by tedu@  Mon, 17 Aug 2015 21:17:42 -0400
 217   loc *  exist **  algo ***  size *  imp **
 218
 219 - support mdoc(7) and man(7) macros inside tbl(7) code;
 220   probably requires the parser reorg and letting tbl(7)
 221   use roff_node such that macro sets can mix;
 222   informed by bapt@ that FreeBSD needs this.
 223   loc ***  exist **  algo ***  size **  imp ***
 224
 225 - look at the POSIX manuals in the books/man-pages-posix port,
 226   they use some unsupported tbl(7) features.
 227   loc *  exist **  algo **  size **  imp ***
 228
 229 - use Unicode U+2500 to U+256C for table borders
 230   in tbl(7) -Tutf-8 output
 231   suggested by bentley@  Tue, 14 Oct 2014 04:10:55 -0600
 232   loc *  exist **  algo *  size *  imp **
 233
 234 --- missing eqn features -----------------------------------------------
 235
 236 - In a matrix, break the output line after each matrix line.
 237   Found in the discussion at CDBUG 2015.
 238   Suggested by Avi Weinstock.
 239   loc *  exist *  algo *  size *  imp **
 240
 241 - The "size" keyword is parsed, but ignored by the formatter.
 242   loc *  exist *  algo *  size *  imp *
 243
 244 - The spacing characters `~', `^', and tab are currently ignored,
 245   see User's Guide (Second Edition) page 2 section 4.
 246   loc *  exist *  algo **  size *  imp **
 247
 248 - Mark and lineup are parsed and ignored,
 249   see User's Guide (Second Edition) page 5 section 15.
 250   loc **  exist **  algo **  size **  imp **
 251
 252 --- missing misc features ----------------------------------------------
 253
 254 - italic correction (\/) in PostScript mode
 255   Werner LEMBERG on groff at gnu dot org  Sun, 10 Nov 2013 12:47:46
 256   loc **  exist **  algo *  size *  imp *
 257
 258 - change the default PAGER to more -Es and use the pager
 259   even for apropos title line output; req by bapt@
 260   loc *  exist *  algo *  size *  imp ***
 261
 262 - clean up escape sequence handling, creating three classes:
 263   (1) fully implemented, or parsed and ignored without loss of content
 264   (2) unimplemented, potentially causing loss of content
 265       or serious mangling of formatting (e.g. \n) -> ERROR
 266       see textproc/mgdiff(1) for nice examples
 267   (3) undefined, just output the character -> perhaps WARNING
 268   loc ***  exist **  algo **  size **  imp *** (parser reorg helps)
 269
 270 - kettenis wants base roff, ms, and me  Fri, 1 Jan 2010 22:13:15 +0100 (CET)
 271   loc **  exist **  algo **  size ***  imp *
 272
 273 - Vsevolod Stakhov (FreeBSD) needs either a markdown output formatter
 274   for mandoc -mdoc or a markdown to mdoc converter because they
 275   have to maintain manuals needed both in markdown and mdoc format.
 276   Look at the libsoldout (markdown -> whatever)
 277   loc *  exist *  algo *  size **  imp **
 278
 279 --- compatibility checks -----------------------------------------------
 280
 281 - is .Bk implemented correctly in modern groff?
 282   sobrado@  Tue, 19 Apr 2011 22:12:55 +0200
 283
 284 - compare output to Heirloom roff, Solaris roff, and
 285   http://repo.or.cz/w/neatroff.git  http://litcave.rudi.ir/
 286
 287 - look at AT&T DWB http://www2.research.att.com/sw/download
 288   Carsten Kunze <carsten dot kunze at arcor dot de> has patches
 289   Mon, 4 Aug 2014 17:01:28 +0200
 290
 291 - look at pages generated from reStructeredText, e.g. devel/mercurial hg(1)
 292   These are a weird mixture of man(7) and custom autogenerated low-level
 293   roff stuff.  Figure out to what extent we can cope.
 294   For details, see http://docutils.sourceforge.net/rst.html
 295   noted by stsp@  Sat, 24 Apr 2010 09:17:55 +0200
 296   reminded by nicm@  Mon, 3 May 2010 09:52:41 +0100
 297
 298 - look at pages generated from ronn(1) github.com/rtomayko/ronn
 299   (based on markdown)
 300
 301 - look at pages generated from Texinfo source by yat2m, e.g. security/gnupg
 302   First impression is not that bad.
 303
 304 - look at pages generated by pandoc; see
 305   https://github.com/jgm/pandoc/blob/master/src/Text/Pandoc/Writers/Man.hs
 306   porting planned by kili@  Thu, 19 Jun 2014 19:46:28 +0200
 307
 308 - check compatibility with Plan9:
 309   http://swtch.com/usr/local/plan9/tmac/tmac.an
 310   http://swtch.com/plan9port/man/man7/man.html
 311   "Anthony J. Bentley" <anthonyjbentley@gmail.com> 28 Dec 2010 21:58:40 -0700
 312
 313 - check compatibility with COHERENT troff:
 314   http://www.nesssoftware.com/home/mwc/source.php
 315
 316 - check compatibility with the man(7) formatter
 317   https://raw.githubusercontent.com/rofl0r/hardcore-utils/master/man.c
 318
 319 - check compatibility with
 320   http://ikiwiki.info/plugins/contrib/mandoc/
 321   https://github.com/schmonz/ikiwiki/compare/mandoc
 322   Amitai Schlair  Mon, 19 May 2014 14:05:53 -0400
 323
 324 ************************************************************************
 325 * formatting issues: ugly output
 326 ************************************************************************
 327
 328 - revisit empty in-line macros
 329   look at the difference between "Em x Em ." and "Sq x Em ."
 330   Carsten Kunze  Fri, 12 Dec 2014 00:15:41 +0100
 331   loc *** exist *** algo *** size * imp **
 332
 333 - a column list with blank `Ta' cells triggers a spurious
 334   start-with-whitespace printing of a newline
 335
 336 - In .Bl -column, .It a<tab>"b<tab>c"
 337   shows the quotes in groff, but not in mandoc
 338   loc * exist *** algo ** size * imp **
 339
 340 - In .Bl -column,
 341   .It Em Authentication<tab>Key Length
 342   ought to render "Key Length" with emphasis, too,
 343   see OpenBSD iked.conf(5).
 344   reported again Nicolas Joly via wiz@ Wed, 12 Oct 2011 00:20:00 +0200
 345   loc *  exist ***  algo ***  size **  imp ***
 346
 347 - empty phrases in .Bl column produce too few blanks
 348   try e.g. .Bl -column It Ta Ta
 349   reported by millert Fri, 02 Apr 2010 16:13:46 -0400
 350   loc *  exist ***  algo ***  size *  imp **
 351
 352 - .%T can have trailing punctuation.  Currently, it puts the trailing
 353   punctuation into a trailing MDOC_TEXT element inside its own scope.
 354   That element should rather be outside its scope, such that the
 355   punctuation does not get underlines.  This is not trivial to
 356   implement because .%T then needs some features of in_line_eoln() -
 357   slurp all arguments into one single text element - and one feature
 358   of in_line() - put trailing punctuation out of scope.
 359   Found in mount_nfs(8) and exports(5), search for "Appendix".
 360   loc **  exist **  algo ***  size *  imp **
 361
 362 - Trailing punctuation after .%T triggers EOS spacing, at least
 363   outside .Rs (eek!).  Simply setting ARGSFL_DELIM for .%T is not
 364   the right solution, it sends mandoc into an endless loop.
 365   reported by Nicolas Joly  Sat, 17 Nov 2012 11:49:54 +0100
 366   loc *  exist **  algo **  size *  imp **
 367
 368 - global variables in the SYNOPSIS of section 3 pages
 369   .Vt vs .Vt/.Va vs .Ft/.Va vs .Ft/.Fa ...
 370   from kristaps@  Tue, 08 Jun 2010 11:13:32 +0200
 371
 372 - in enclosures, mandoc sometimes fancies a bogus end of sentence
 373   reminded by jmc@  Thu, 23 Sep 2010 18:13:39 +0059
 374   loc *  exist **  algo ***  size *  imp ***
 375
 376 - a line starting with "\fB something" counts as starting with whitespace
 377   and triggers a line break; found in audio/normalize-mp3(1)
 378   loc **  exist *  algo **  size *  imp **
 379
 380 - formatting /usr/local/man/man1/latex2man.1 with groff and mandoc
 381   reveals lots of bugs both in groff and mandoc...
 382   reported by bentley@  Wed, 22 May 2013 23:49:30 -0600
 383
 384 --- PDF issues ---------------------------------------------------------
 385
 386 - PDF output doesn't use a monospaced font for .Bd -literal
 387   Example: "mandoc -Tpdf afterboot.8 > output.pdf && pdfviewer output.pdf".
 388   Search the text "Routing tables".
 389   Also check what PostScript mode does when fixing this.
 390   reported by juanfra@ Wed, 04 Jun 2014 21:44:58 +0200
 391   instructions from juanfra@  Wed, 11 Jun 2014 02:21:01 +0200
 392     add a new <</Type /Font>> block to the PDF files with /BaseFont /Courier
 393     and change the /Name from /F0 to the new font (/F5 (?)).
 394   loc *  exist **  algo **  size *  imp **
 395
 396 --- HTML issues --------------------------------------------------------
 397
 398 - .Bf at the beginning of a paragraph inserts a bogus 1ex horizontal
 399   space, see for example random(3).  Introduced in
 400   http://mdocml.bsd.lv/cgi-bin/cvsweb/mdoc_html.c.diff?r1=1.91&r2=1.92
 401   reported by deraadt@ Mon, 28 Sep 2015 20:14:13 -0600 (MDT)
 402   loc **  exist **  algo **  size *  imp *
 403
 404 - jsg on icb, Nov 3, 2014:
 405   try to guess Xr in man(7) for hyperlinking
 406   and render them with <a class="Xr" href=...>
 407   https://github.com/Debian/debiman/issues/15
 408   loc *  exist *  algo **  size **  imp **
 409
 410 - The tables used to render the three-part page headers actually force
 411   the width of the <body> to the max-width given for <html>.
 412   Not yet sure how to fix that...
 413   Observed by an Anonymous Coward on undeadly.org:
 414   http://undeadly.org/cgi?action=article&sid=20140925064244&pid=1
 415   loc *  exist *  algo **  size *  imp ***
 416
 417 - consider whether <var> can be used for Ar Dv Er Ev Fa Va.
 418   from bentley@  Wed, 13 Aug 2014 09:17:55 -0600
 419
 420 - generate <img> tags in HTML
 421   idea from florian@  Tue, 7 Apr 2015 00:26:28 +0000
 422   may be possible to implement with .Lk img://something.png alt_text
 423
 424 - check https://github.com/trentm/mdocml
 425
 426 ************************************************************************
 427 * formatting issues: gratuitous differences
 428 ************************************************************************
 429
 430 - .Fn reopens a new scope after punctuation in mandoc,
 431   but closes its scope for good in groff.
 432   Do we want to change mandoc or groff?
 433   Steffen Nurpmeso  Sat, 08 Nov 2014 13:34:59 +0100
 434   loc *  exist **  algo **  size *  imp **
 435
 436 - In .Bl -enum -width 0n, groff continues one the same line after
 437   the number, mandoc breaks the line.
 438   mail to kristaps@  Mon, 20 Jul 2009 02:21:39 +0200
 439   loc *  exist **  algo **  size *  imp **
 440
 441 - .Pp between two .It in .Bl -column should produce one,
 442   not two blank lines, see e.g. login.conf(5).
 443   reported by jmc@  Sun, 17 Apr 2011 14:04:58 +0059
 444   reported again by sthen@  Wed, 18 Jan 2012 02:09:39 +0000 (UTC)
 445   loc *  exist ***  algo **  size *  imp **
 446
 447 - If the *first* line after .It is .Pp, break the line right after
 448   the tag, do not pad with space characters before breaking.
 449   See the description of the a, c, and i commands in sed(1).
 450   loc *  exist **  algo **  size *  imp **
 451
 452 - If the first line after .It is .D1, do not assert a blank line
 453   in between, see for example tmux(1).
 454   reported by nicm@  13 Jan 2011 00:18:57 +0000
 455   loc *  exist **  algo **  size *  imp **
 456
 457 - Trailing punctuation after .It should trigger EOS spacing.
 458   reported by Nicolas Joly  Sat, 17 Nov 2012 11:49:54 +0100
 459   Probably, this should be fixed somewhere in termp_it_pre(), not sure.
 460   loc *  exist **  algo **  size *  imp **
 461
 462 - .Nx 1.0a
 463   should be "NetBSD 1.0A", not "NetBSD 1.0a",
 464   see OpenBSD ccdconfig(8).
 465   loc *  exist *  algo *  size *  imp **
 466
 467 - In .Bl -tag, if a tag exceeds the right margin and must be continued
 468   on the next line, it must be indented by -width, not width+1;
 469   see "rule block|pass" in OpenBSD ifconfig(8).
 470   loc *  exist ***  algo **  size *  imp **
 471
 472 - When the -width string contains macros, the macros must be rendered
 473   before measuring the width, for example
 474     .Bl -tag -width ".Dv message"
 475   in magic(5), located in src/usr.bin/file, is the same
 476   as -width 7n, not -width 11n.
 477   The same applies to .Bl -column column widths;
 478   reported again by Nicolas Joly Thu, 1 Mar 2012 13:41:26 +0100 via wiz@ 5 Mar
 479   reported again by Franco Fichtner Fri, 27 Sep 2013 21:02:28 +0200
 480   loc ***  exist ***  algo ***  size **  imp ***
 481   An easy partial fix would be to just skip the first word if it starts
 482   with a dot, including any following white space, when measuring.
 483   loc *  exist *  algo *  size *  imp ***
 484
 485 - The \& zero-width character counts as output.
 486   That is, when it is alone on a line between two .Pp,
 487   we want three blank lines, not two as in mandoc.
 488   loc **  exist **  algo **  size *  imp **
 489
 490 - Header lines of excessive length:
 491   Port OpenBSD man_term.c rev. 1.25 to mdoc_term.c
 492   and document it in mdoc(7) and man(7) COMPATIBILITY
 493   found while talking to Chris Bennett
 494   loc *  exist *  algo *  size *  imp *
 495
 496 - Sequences of multiple man(7) paragraphs (.PP, .IP) interspersed
 497   with .ps and .nf/.fi produce execessive blank lines, see libJudy
 498   and graphics/dcmtk.  The parser reorg may help with this.
 499
 500 - trailing whitespace must be ignored even when followed by a font escape,
 501   see for example
 502     makes
 503     \fBdig \fR
 504     operate in batch mode
 505   in dig(1).
 506   loc **  exist **  algo **  size *  imp **
 507
 508 ************************************************************************
 509 * warning issues
 510 ************************************************************************
 511
 512 - provide a way in mandoc(1) to warn about broken .Xr links;
 513   probably cannot be on by default in -Tlint because it needs
 514   to access the manpath and mandoc.db(3) after parsing.
 515   asked for by jmc@ Fri, 4 Dec 2015 22:39:40 +0000
 516
 517 - warn when .Sh or .Ss contain other macros
 518   Steffen Nurpmeso, savannah.gnu.org/bugs/index.php?45034
 519   loc *  exist *  algo *  size *  imp **
 520
 521 - warn about attempts to call non-callable macros
 522   Steffen Nurpmeso  Tue, 11 Nov 2014 22:55:16 +0100
 523   Note that formatting is inconsistent in groff.
 524   .Fn Po prints "Po()", .Ar Sh prints "file ..." and no "Sh".
 525   Relatively hard because the relevant code is scattered
 526   all over mdoc_macro.c and all subtly different.
 527   loc **  exist **  algo **  size **  imp **
 528
 529 - warn about "new sentence, new line"
 530   loc **  exist **  algo ***  size *  imp **
 531
 532 - mandoc_special does not really check the escape sequence,
 533   but just the overall format
 534   loc **  exist **  algo ***  size **  imp **
 535
 536 - integrate mdoclint into mandoc ("end-of-line whitespace" thread)
 537   from jmc@  Mon, 13 Jul 2009 17:12:09 +0100
 538   from kristaps@  Mon, 13 Jul 2009 18:34:53 +0200
 539   from jmc@  Mon, 13 Jul 2009 17:45:37 +0059
 540   from kristaps@  Mon, 13 Jul 2009 19:02:03 +0200
 541   (mostly done, check what remains)
 542
 543 - -Tlint parser errors and warnings to stdout
 544   to tech@mdocml, naddy@  Wed, 28 Sep 2011 11:21:46 +0200
 545   wait!  kristaps@  Sun, 02 Oct 2011 17:12:52 +0200
 546
 547 ************************************************************************
 548 * documentation issues
 549 ************************************************************************
 550
 551 - mention hyphenation rules:
 552   breaking at letter-letter in text mode (not macro args)
 553   proper hyphenation is unimplemented
 554
 555 - talk about spacing around delimiters
 556   to jmc@, kristaps@  Sat, 23 Apr 2011 17:41:27 +0200
 557
 558 - mark macros as: page structure domain, manual domain, general text domain
 559   is this useful?
 560
 561 - mention /usr/share/misc/mdoc.template in mdoc(7)?
 562
 563 - Is all the content from http://www.std.com/obi/BSD/doc/usd/28.tbl/tbl
 564   covered in tbl(7)?
 565
 566 ************************************************************************
 567 * performance issues
 568 ************************************************************************
 569
 570 - Why are we using MAP_SHARED, not MAP_PRIVATE for mmap(2)?
 571   from kristaps@  Sat, 09 Aug 2014 13:51:36 +0200
 572
 573 Several areas can be cleaned up to make mandoc even faster.  These are
 574
 575 - improve hashing mechanism for macros (quite important: performance)
 576
 577 - improve hashing mechanism for characters (not as important)
 578
 579 - the PDF file is HUGE: this can be reduced by using relative offsets
 580
 581 - instead of re-initialising the roff predefined-strings set before each
 582   parse, create a read-only version the first time and copy it
 583   loc *  exist **  algo **  size *  imp **
 584
 585 ************************************************************************
 586 * structural issues
 587 ************************************************************************
 588
 589 - POSIX says in the documentation of sysconf(3) that PATH_MAX
 590   is allowed to be so large that it is a bad idea to use it
 591   for sizing static buffers.  So use dynamic buffers throughout.
 592   See the file test-PATH_MAX.c for details.
 593   Found by Aaron M. Ucko in the GNU Hurd via Bdale Garbee,
 594   https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=829624
 595
 596 - We use the input line number at several places to distinguish
 597   same-line from different-line input.  That plainly doesn't work
 598   with user-defined macros, leading to random breakage.
 599
 600 - Find better ways to prevent endless loops
 601   in roff(7) macro and string expansion.
 602
 603 - Finish cleanup of date handling.
 604   Decide which formats should be recognized where.
 605   Update both mdoc(7) and man(7) documentation.
 606   Triggered by  Tim van der Molen  Tue, 22 Feb 2011 20:30:45 +0100
 607
 608 - struct mparse refactoring
 609   Steffen Nurpmeso  Thu, 04 Sep 2014 12:50:00 +0200
 610
 611 ************************************************************************
 612 * CGI issues
 613 ************************************************************************
 614
 615  - Enable HTTP compression by detecting gzip encoding and filtering
 616    output through libz.
 617  - Sandbox (see OpenSSH).
 618  - Enable caching support via HTTP 304 and If-Modified-Since.
 619  - Allow for cgi.h to be overridden by CGI environment variables.
 620    Otherwise, binary distributions will inherit the compile-time
 621    behaviour, which is not optimal.
 622  - Have Mac OSX systems automatically disable -static compilation of the
 623    CGI: -static isn't supported.
 624
 625 ************************************************************************
 626 * to improve in the groff_mdoc(7) macros
 627 ************************************************************************
 628
 629 - use uname(1) to set doc-default-operating-system at install time
 630   tobimensch  Mon, 1 Dec 2014 00:25:07 +0100