path: root/TODO

************************************************************************
* Official mandoc TODO.
* $Id$
************************************************************************

************************************************************************
* parser bugs
************************************************************************

- .TP before .SH is still FATAL in man(7)
  reported by brad@  Sat, 15 Jan 2011 15:54:54 -0500

- the roff parser doesn't tolerate additional characters between
  a macro and the \} terminating a conditional block, e.g.
  .if n \{
  .br \}
  reported by ulrich spoerlein  Tue, 19 Oct 2010 20:39:50 +0200

************************************************************************
* formatter bugs
************************************************************************

************************************************************************
* missing features
************************************************************************

--- missing roff features ----------------------------------------------

- .ad (adjust margins)
  .ad l -- adjust left margin only (flush left)
  .ad r -- adjust right margin only (flush right)
  .ad c -- center text on line
  .ad b -- adjust both margins (alias: .ad n)
  .na   -- temporarily disable adjustment without changing the mode
  .ad   -- re-enable adjustment without changing the mode
  Adjustment mode is ignored while in no-fill mode (.nf).

- .it (line traps) occur in mysql(1), yasm_arch(7)
  generated by DocBook XSL Stylesheets v1.71.1 <http://docbook.sf.net/>
  reported by brad@  Sat, 15 Jan 2011 15:48:18 -0500

- .ns (no-space mode) occurs in xine-config(1)
  reported by brad@  Sat, 15 Jan 2011 15:45:23 -0500

- xloadimage(1) wants .ti (temporary indent), rep by naddy@

- .ta (tab settings) occurs in ircbug(1) and probably gnats(1)
  reported by brad@  Sat, 15 Jan 2011 15:50:51 -0500

- pod2man expects `tr' to be implemented for \*(-- to work

- \c (interrupted text) occurs in chat(8)

- \f(CW (constant width font) occurs in rsyncd.conf(5).
  I think we should treat unknown/unavailable fonts as \fR
  such that switching back with \fP works correctly -
  and doesn't revert the _previous_ \fP.

--- missing mdoc features ----------------------------------------------

- fix bad block nesting involving multiple identical explicit blocks
  see the OpenBSD mdoc_macro.c 1.47 commit message

- .Bl -column .Xo support is missing
  ultimate goal:
  restore .Xr and .Dv to
  lib/libc/compat-43/sigvec.3
  lib/libc/gen/signal.3
  lib/libc/sys/sigaction.2

- edge case: decide how to deal with blk_full bad nesting, e.g.
  .Sh .Nm .Bk .Nm .Ek .Sh found by jmc@ in ssh-keygen(1)
  from jmc@  Wed, 14 Jul 2010 18:10:32 +0100

- \\ is now implemented correctly
  * when defining strings and macros using .ds and .de
  * when parsing roff(7) and man(7) macro arguments
  It does not yet work in mdoc(7) macro arguments
  because libmdoc does not yet use mandoc_getarg().
  Also check what happens in plain text, it must be identical to \e.

- .Bd -filled should not be the same as .Bd -ragged, but align both
  the left and right margin.  In groff, it is implemented in terms
  of .ad b, which we don't have either.  Found in cksum(1).

- implement blank `Bl -column', such as
  .Bl -column
  .It foo Ta bar
  .El

- explicitly disallow nested `Bl -column', which would clobber internal
  flags defined for struct mdoc_macro

- inside `.Bl -column' phrases, punctuation is handled like normal
  text, e.g. `.Bl -column .It Fl x . Ta ...' should give "-x -."

- inside `.Bl -column' phrases, TERMP_IGNDELIM handling by `Pf'
  is not safe, e.g. `.Bl -column .It Pf a b .' gives "ab."
  but should give "ab ."

- set a meaningful default if no `Bl' list type is assigned

- have a blank `It' head for `Bl -tag' not puke

- prohibit `Nm' from having non-text HEAD children
  (e.g., NetBSD mDNSShared/dns-sd.1)
  (mdoc_html.c and mdoc_term.c `Nm' handlers can be slightly simplified)

--- missing man features -----------------------------------------------

- groff an-ext.tmac macros (.UR, .UE) occur in xine(5)
  reported by brad@  Sat, 15 Jan 2011 15:45:23 -0500

--- missing tbl features -----------------------------------------------

- implement basic non-parametric .de to support e.g. sox(1)
  reported by naddy@ Sat, 16 Oct 2010 23:51:57 +0200
  *** sox(1) still doesn't work, tbl(1) errors need investigation

--- missing misc features ----------------------------------------------

- clean up escape sequence handling, creating three classes:
  (1) fully implemented, or parsed and ignored without loss of content
  (2) unimplemented, potentially causing loss of content
      or serious mangling of formatting (e.g. \n) -> ERROR
      see textproc/mgdiff(1) for nice examples
  (3) undefined, just output the character -> perhaps WARNING

- The \t escape sequence is the same as a literal tab, see for example
  the ASCII table in hexdump(1) where
    .Bl -column \&000_nu \&001_so \&002_st \&003_et \&004_eo
    .It \&000\ nul\t001\ soh\t002\ stx\t003\ etx\t004\ eot\t005\ enq
  produces
    000 nul  001 soh  002 stx  003 etx  004 eot  005 enq
  and the example in oldrdist(1)

- look at pages generated from reStructeredText, e.g. devel/mercurial hg(1)
  These are a weird mixture of man(7) and custom autogenerated low-level
  roff stuff.  Figure out to what extent we can cope.
  For details, see http://docutils.sourceforge.net/rst.html
  noted by stsp@  Sat, 24 Apr 2010 09:17:55 +0200
  reminded by nicm@  Mon, 3 May 2010 09:52:41 +0100

- check compatibility with Plan9:
  http://swtch.com/usr/local/plan9/tmac/tmac.an
  http://swtch.com/plan9port/man/man7/man.html
  "Anthony J. Bentley" <anthonyjbentley@gmail.com> 28 Dec 2010 21:58:40 -0700

************************************************************************
* formatting issues: ugly output
************************************************************************

- a column list with blank `Ta' cells triggers a spurrious
  start-with-whitespace printing of a newline

- double quotes inside double quotes are escaped by doubling them
  implement this in mdoc(7), too
  so far, we only have it in roff(7) and man(7)
  reminded by millert@  Thu, 09 Dec 2010 17:29:52 -0500

- perl(1) SYNOPSIS looks bad; reported by deraadt@
  1) man(7) seems to need SYNOPSIS .Nm blocks, too

- In .Bl -column,
  .It Em Authentication<tab>Key Length
  ought to render "Key Length" with emphasis, too,
  see OpenBSD iked.conf(5).

- empty phrases in .Bl column produce too few blanks
  try e.g. .Bl -column It Ta Ta
  reported by millert Fri, 02 Apr 2010 16:13:46 -0400

- .%T can have trailing punctuation.  Currently, it puts the trailing
  punctuation into a trailing MDOC_TEXT element inside its own scope.
  That element should rather be outside its scope, such that the
  punctuation does not get underlines.  This is not trivial to
  implement because .%T then needs some features of in_line_eoln() -
  slurp all arguments into one single text element - and one feature
  of in_line() - put trailing punctuation out of scope.
  Found in mount_nfs(8) and exports(5), search for "Appendix".

- in enclosures, mandoc sometimes fancies a bogus end of sentence
  reminded by jmc@  Thu, 23 Sep 2010 18:13:39 +0059

************************************************************************
* formatting issues: gratuitious differences
************************************************************************

- .Rv (and probably .Ex) print different text if an `Nm' has been named
  or not (run a manual without `Nm blah' to see this).  I'm not sure
  that this exists in the wild, but it's still an error.

- In .Bl -bullet, the groff bullet is "+\b+\bo\bo", the mandoc bullet
  is just "o\bo".
  see for example OpenBSD ksh(1)

- The characters "|" and "\*(Ba" should never be bold,
  not even in the middle of a word, e.g. ".Cm b\*(Bac" in
  "mknod [-m mode] name b|c major minor"
  in OpenBSD ksh(1)

- A bogus .Pp between two .It must not produce a double blank line,
  see between -R and -r in OpenBSD rm(1), before "update" in mount(8),
  or in DIAGNOSTICS in init(8), or before "is always true" in ksh(1).
  The same happens with .Pp just before .El, see bgpd.conf(5).
  Also have `It' complain if `Pp' is invoked at certain times (not
  -compact?).

- If the *first* line after .It is .Pp, break the line right after
  the tag, do not pad with space characters before breaking.
  See the description of the a, c, and i commands in sed(1).

- If the first line after .It is .D1, do not assert a blank line
  in between, see for example tmux(1).
  reported by nicm@  13 Jan 2011 00:18:57 +0000

- .Nx 1.0a
  should be "NetBSD 1.0A", not "NetBSD 1.0a",
  see OpenBSD ccdconfig(8).

- In .Bl -tag, if a tag exceeds the right margin and must be continued
  on the next line, it must be indented by -width, not width+1;
  see "rule block|pass" in OpenBSD ifconfig(8).

- When the -width string contains macros, the macros must be rendered
  before measuring the width, for example
    .Bl -tag -width ".Dv message"
  in magic(5), located in src/usr.bin/file, is the same
  as -width 7n, not -width 11n.

- The \& zero-width character counts as output.
  That is, when it is alone on a line between two .Pp,
  we want three blank lines, not two as in mandoc.

- When .Fn arguments exceed one output line, all but the first
  should be indented, see e.g. rpc(3);
  reported by jmc@ on discuss@  Fri, 29 Oct 2010 13:48:33 +0100

- .Ns should work when called at the end of an input line, see
  the following code in vi(1):
    .It Xo
    .Op Ar line
    .Cm a Ns Op Cm ppend Ns
    .Op Cm !\&
    .Xc
    The input text is appended after the specified line.

- Header lines of excessive length:
  Port OpenBSD man_term.c rev. 1.25 to mdoc_term.c
  and document it in mdoc(7) and man(7) COMPATIBILITY
  found while talking to Chris Bennett

- In man(7), the sequence
    .HP
    one line of regular text
    .SH
  should not produce two blank lines before the .SH,
  see for example named-checkconf(8).

- In man(7), the sequence
    regular text
    .RS
    .IP
  should have a blank line between the text and the beginning of the
  indented paragraph, see for example sudo(1).

- In man(7), the sequence
    .SH HEADER
    <blank line>
    .PP
    regular text
  should not produce any blank lines between the header and the text,
  see for example rsync(1).
  Reported by naddy@  Mon, 28 Mar 2011 20:45:42 +0200

- In man(7), the sequence
    regular text
    .PP
    .RS
    indented text
  should produce one blank line between the regular and indented texts,
  see for example rsync(1), and
    .RE
    <blank line>
    .PP
    .RS
  should produce two,not one blank lines.
  Reported by naddy@  Mon, 28 Mar 2011 20:45:42 +0200

- In man(7), the sequence
    regular text
    .IP
    .IP "tag"
    indented text
  should produce one, not four blank lines between the regular text
  and the tag, see for example rsync(1).
  Likewise,
    regular text
    .IP
    indented text
  should produce one, not two blank lines in between, and
    regular text
    .IP
    .RS
    .IP tag
    indented text
  should produce one, not three blank lines.
  Reported by naddy@  Mon, 28 Mar 2011 20:45:42 +0200

- At least sometimes, .sp is ignored right after .SH; see named.conf(5).

- trailing whitespace must be ignored even when followed by a font escape,
  see for example 
    makes
    \fBdig \fR
    operate in batch mode
  in dig(1).

************************************************************************
* error reporting issues
************************************************************************

************************************************************************
* performance issues
************************************************************************

Several areas can be cleaned up to make mandoc even faster.  These are 

- improve hashing mechanism for macros (quite important: performance)

- improve hashing mechanism for characters (not as important)

- the PDF file is HUGE: this can be reduced by using relative offsets

************************************************************************
* structural issues
************************************************************************

- Find better ways to prevent endless loops
  in roff(7) macro and string expansion.
 
- Finish cleanup of date handling.
  Decide which formats should be recognized where.
  Update both mdoc(7) and man(7) documentation.
  Triggered by  Tim van der Molen  Tue, 22 Feb 2011 20:30:45 +0100