annotate for difficulty, and some minor cleanup

1 files changed, 98 insertions, 8 deletions

diff --git a/TODO b/TODO
index d020d953..d077ef26 100644
--- a/TODO
+++ b/TODO
@@ -3,6 +3,35 @@
 * $Id$
 ************************************************************************
 
+Many issues are annotated for difficulty as follows:
+
+ - loc = locality of the issue
+    *    single file issue, affects file only, or very few
+    **   single module issue, affects several files of one module
+    ***  cross-module issue, significantly impacts multiple modules
+         and may require substantial changes to internal interfaces
+ - exist = difficulty of the existing code in this area
+    *    affected code is straightforward and easy to read and change
+    **   affected code is somewhat complex, but once you understand
+         the design, not particularly difficult to understand
+    ***  affected code uses a special, exceptionally tricky design
+ - algo = difficulty of the new algorithm to be written
+    *    the required logic and code is straightforward
+    **   the required logic is somewhat complex and needs a careful design
+    ***  the required logic is exceptionally tricky,
+         maybe an approach to solve that is not even known yet
+ - size = the amount of code to be written or changed
+    *    a small number of lines (at most 100, usually much less)
+    **   a considerable amount of code (several dozen to a few hundred)
+    ***  a large amount of code (many hundreds, maybe thousands)
+ - imp = importance of the issue
+    *    mostly for completeness
+    **   would be nice to have
+    ***  issue causes considerable inconvenience
+
+Obviously, as the issues have not been solved yet, these annotations
+are mere guesses, and some may be wrong.
+
 ************************************************************************
 * crashes
 ************************************************************************
@@ -10,6 +39,7 @@
 - The abort() in bufcat(), html.c, can be triggered via buffmt_includes()
   by running -Thtml -Oincludes on a file containing a long .In argument.
   Fixing this will probably require reworking the whole bufcat() concept.
+  loc **  exist *  algo *  size **  imp **
 
 ************************************************************************
 * missing features
@@ -25,49 +55,62 @@
   .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).
+  loc ***  exist ***  algo **  size **  imp **  (parser reorg would help)
 
 - .fc (field control)
   found by naddy@ in xloadimage(1)
+  loc **  exist ***  algo *  size *  imp *
   
 - .nr third argument (auto-increment step size, requires \n+)
   found by bentley@ in sbcl(1)  Mon, 9 Dec 2013 18:36:57 -0700
+  loc *  exist *  algo *  size *  imp **
 
 - .ns (no-space mode) occurs in xine-config(1)
   reported by brad@  Sat, 15 Jan 2011 15:45:23 -0500
+  loc ***  exist ***  algo ***  size **  imp *
 
 - .ta (tab settings) occurs in ircbug(1) and probably gnats(1)
   reported by brad@  Sat, 15 Jan 2011 15:50:51 -0500
   also Tcl_NewStringObj(3) via wiz@  Wed, 5 Mar 2014 22:27:43 +0100
+  loc **  exist ***  algo **  size **  imp **
 
 - .ti (temporary indent)
   found by naddy@ in xloadimage(1)
   found by bentley@ in nmh(1)  Mon, 23 Apr 2012 13:38:28 -0600
+  loc **  exist **  algo **  size *  imp ** (parser reorg helps a lot)
 
 - .while and .shift 
   found by jca@ in ratpoison(1)  Sun, 30 Jun 2013 12:01:09 +0200
+  loc *  exist **  algo **  size **  imp **
 
 - \c (interrupted text) should prevent the line break
   even inside .Bd literal; that occurs in chat(8)
   also found in cclive(1) - DocBook output
+  loc **  exist ***  algo **  size *  imp *
 
 - \h horizontal move
   found in cclive(1) DocBook output
   Anthony J. Bentley on discuss@  Sat, 21 Sep 2013 22:29:34 -0600
+  loc **  exist **  algo **  size *  imp ** (parser reorg helps a lot)
 
 - \n+ and \n- numerical register increment and decrement
   found by bentley@ in sbcl(1)  Mon, 9 Dec 2013 18:36:57 -0700
+  loc *  exist *  algo *  size *  imp **
 
-- \w'' width measurements
+- \w'' improve width measurements
   would not be very useful without an expression parser, see below
   needed for Tcl_NewStringObj(3) via wiz@  Wed, 5 Mar 2014 22:27:43 +0100
+  loc **  exist ***  algo ***  size *  imp ***
 
 - using undefined strings or macros defines them to be empty
   wl@  Mon, 14 Nov 2011 14:37:01 +0000
+  loc *  exist *  algo *  size *  imp *
 
 --- missing mdoc features ----------------------------------------------
 
 - fix bad block nesting involving multiple identical explicit blocks
   see the OpenBSD mdoc_macro.c 1.47 commit message
+  loc *  exist ***  algo ***  size *  imp **
 
 - .Bl -column .Xo support is missing
   ultimate goal:
@@ -75,10 +118,12 @@
   lib/libc/compat-43/sigvec.3
   lib/libc/gen/signal.3
   lib/libc/sys/sigaction.2
+  loc *  exist ***  algo ***  size *  imp **
 
 - 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
+  loc *  exist ***  algo ***  size **  imp **
 
 - \\ is now implemented correctly
   * when defining strings and macros using .ds and .de
@@ -92,18 +137,22 @@
   we don't have either.
   Besides, groff has bug causing text right *before* .Bd -centered
   to be centered as well.
+  loc ***  exist ***  algo **  size **  imp **  (parser reorg would help)
 
 - .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).
+  loc ***  exist ***  algo **  size **  imp **  (parser reorg would help)
 
 - implement blank `Bl -column', such as
   .Bl -column
   .It foo Ta bar
   .El
+  loc *  exist ***  algo ***  size *  imp *
 
 - explicitly disallow nested `Bl -column', which would clobber internal
   flags defined for struct mdoc_macro
+  loc *  exist *  algo *  size *  imp **
 
 - In .Bl -column .It, the end of the line probably has to be regarded
   as an implicit .Ta, if there could be one, see the following mildly
@@ -114,6 +163,7 @@
     Default search path.
   reported by Michal Mazurek <akfaew at jasminek dot net>
   via jmc@ Thu, 7 Apr 2011 16:00:53 +0059
+  loc *  exist ***  algo **  size *  imp **
 
 - inside `.Bl -column' phrases, punctuation is handled like normal
   text, e.g. `.Bl -column .It Fl x . Ta ...' should give "-x -."
@@ -123,11 +173,14 @@
   but should give "ab ."
 
 - set a meaningful default if no `Bl' list type is assigned
+  loc *  exist *  algo *  size *  imp **  (already done?)
 
 - have a blank `It' head for `Bl -tag' not puke
+  loc *  exist *  algo *  size *  imp **  (already done?)
 
 - check whether it is correct that `D1' uses INDENT+1;
   does it need its own constant?
+  loc *  exist **  algo **  size *  imp **
 
 - prohibit `Nm' from having non-text HEAD children
   (e.g., NetBSD mDNSShared/dns-sd.1)
@@ -138,6 +191,7 @@
   that one uses NOMBRE because it is spanish...
   deraadt tends to think that section-dependent macro behaviour
   is a bad idea in the first place, so this may be irrelevant
+  loc **  exist **  algo **  size *  imp **
 
 - When there is free text in the SYNOPSIS and that free text contains
   the .Nm macro, groff somehow understands to treat the .Nm as an in-line
@@ -146,6 +200,7 @@
   should be, needs investigation.
   uqs@  Thu, 2 Jun 2011 11:03:51 +0200
   uqs@  Thu, 2 Jun 2011 11:33:35 +0200
+  loc *  exist **  algo ***  size *  imp **
 
 --- missing man features -----------------------------------------------
 
@@ -155,31 +210,39 @@
 
 - look at the POSIX manuals in the books/man-pages-posix port,
   they use some unsupported tbl(7) features.
+  loc *  exist **  algo **  size **  imp ***
 
 - use Unicode U+2500 to U+256C for table borders
   in tbl(7) -Tutf-8 output
   suggested by bentley@  Tue, 14 Oct 2014 04:10:55 -0600
+  loc *  exist **  algo *  size *  imp **
 
 - allow standalone `.' to be interpreted as an end-of-layout
   delimiter instead of being thrown away as a no-op roff line
   reported by Yuri Pankov, Wed 18 May 2011 11:34:59 CEST
+  loc **  exist **  algo **  size *  imp **
 
 --- missing eqn features -----------------------------------------------
 
-- set, delim, fonts
+- delim
+  loc **  exist **  algo **  size *  imp ***
 
 - The "size" keyword is parsed, but ignored by the formatter.
+  loc *  exist *  algo *  size *  imp *
 
 - The spacing characters `~', `^', and tab are currently ignored,
   see User's Guide (Second Edition) page 2 section 4.
+  loc *  exist *  algo **  size *  imp **
 
 - Mark and lineup are parsed and ignored,
   see User's Guide (Second Edition) page 5 section 15.
+  loc **  exist **  algo **  size **  imp **
 
 --- missing misc features ----------------------------------------------
 
 - italic correction (\/) in PostScript mode
   Werner LEMBERG on groff at gnu dot org  Sun, 10 Nov 2013 12:47:46
+  loc **  exist **  algo *  size *  imp *
 
 - When makewhatis(8) encounters a FATAL parse error,
   it silently treats the file as formatted, which makes no sense
@@ -187,13 +250,16 @@
   what the manual says at the end of the description.
   The end result will be ENOENT for file names returned
   by mansearch() in manpage.file.
+  loc *  exist *  algo *  size *  imp **
 
 - makewhatis(8) for preformatted pages:
   parse the section number from the header line
   and compare to the section number from the directory name
+  loc *  exist *  algo *  size *  imp **
 
 - Does makewhatis(8) detect missing NAME sections, missing names,
   and missing descriptions in all the file formats?
+  loc *  exist *  algo *  size *  imp ***
 
 - clean up escape sequence handling, creating three classes:
   (1) fully implemented, or parsed and ignored without loss of content
@@ -201,8 +267,10 @@
       or serious mangling of formatting (e.g. \n) -> ERROR
       see textproc/mgdiff(1) for nice examples
   (3) undefined, just output the character -> perhaps WARNING
+  loc ***  exist **  algo **  size **  imp *** (parser reorg helps)
 
 - kettenis wants base roff, ms, and me  Fri, 1 Jan 2010 22:13:15 +0100 (CET)
+  loc **  exist **  algo **  size ***  imp *
 
 --- compatibility checks -----------------------------------------------
 
@@ -253,10 +321,12 @@
   ought to render "Key Length" with emphasis, too,
   see OpenBSD iked.conf(5).
   reported again Nicolas Joly via wiz@ Wed, 12 Oct 2011 00:20:00 +0200
+  loc *  exist ***  algo ***  size **  imp ***
 
 - 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
+  loc *  exist ***  algo ***  size *  imp **
 
 - .%T can have trailing punctuation.  Currently, it puts the trailing
   punctuation into a trailing MDOC_TEXT element inside its own scope.
@@ -266,11 +336,13 @@
   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".
+  loc **  exist **  algo ***  size *  imp **
 
 - Trailing punctuation after .%T triggers EOS spacing, at least
   outside .Rs (eek!).  Simply setting ARGSFL_DELIM for .%T is not
   the right solution, it sends mandoc into an endless loop.
   reported by Nicolas Joly  Sat, 17 Nov 2012 11:49:54 +0100
+  loc *  exist **  algo **  size *  imp **
 
 - global variables in the SYNOPSIS of section 3 pages
   .Vt vs .Vt/.Va vs .Ft/.Va vs .Ft/.Fa ...
@@ -278,6 +350,7 @@
 
 - in enclosures, mandoc sometimes fancies a bogus end of sentence
   reminded by jmc@  Thu, 23 Sep 2010 18:13:39 +0059
+  loc *  exist **  algo ***  size *  imp ***
 
 - formatting /usr/local/man/man1/latex2man.1 with groff and mandoc
   reveals lots of bugs both in groff and mandoc...
@@ -290,6 +363,7 @@
   Search the text "Routing tables".
   Also check what PostScript mode does when fixing this.
   reported by juanfra@ Wed, 04 Jun 2014 21:44:58 +0200
+  loc *  exist **  algo ?  size *  imp **
 
 --- HTML issues --------------------------------------------------------
 
@@ -297,23 +371,20 @@
   hints are easy to find on the web, e.g.
   http://stackoverflow.com/questions/1713048/
   see also matthew@  Fri, 18 Jul 2014 19:25:12 -0700
+  loc *  exist *  algo **  size *  imp ***
 
 - The tables used to render the three-part page headers actually force
   the width of the <body> to the max-width given for <html>.
   Not yet sure how to fix that...
   Observed by an Anonymous Coward on undeadly.org:
   http://undeadly.org/cgi?action=article&sid=20140925064244&pid=1
+  loc *  exist *  algo **  size *  imp ***
 
 - consider whether <var> can be used for Ar Dv Er Ev Fa Va.
   from bentley@  Wed, 13 Aug 2014 09:17:55 -0600
 
 - check https://github.com/trentm/mdocml
 
---- eqn issues ---------------------------------------------------------
-
-- If .EQ follows preceding text, a space should be output between the
-  text and the equation.
-
 ************************************************************************
 * formatting issues: gratuitous differences
 ************************************************************************
@@ -321,39 +392,48 @@
 - .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.
+  loc *  exist *  algo *  size *  imp * (already done?)
 
 - In .Bl -bullet, the groff bullet is "+\b+\bo\bo", the mandoc bullet
-  is just "o\bo".
+  is just "o\bo".  The problem is to not break ps/pdf when fixing.
   see for example OpenBSD ksh(1)
+  loc **  exist **  algo **  size *  imp **
 
 - In .Bl -enum -width 0n, groff continues one the same line after
   the number, mandoc breaks the line.
   mail to kristaps@  Mon, 20 Jul 2009 02:21:39 +0200
+  loc *  exist **  algo **  size *  imp **
 
 - .Pp between two .It in .Bl -column should produce one,
   not two blank lines, see e.g. login.conf(5).
   reported by jmc@  Sun, 17 Apr 2011 14:04:58 +0059
   reported again by sthen@  Wed, 18 Jan 2012 02:09:39 +0000 (UTC)
+  loc *  exist ***  algo **  size *  imp **
 
 - 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).
+  loc *  exist **  algo **  size *  imp **
 
 - 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
+  loc *  exist **  algo **  size *  imp **
 
 - Trailing punctuation after .It should trigger EOS spacing.
   reported by Nicolas Joly  Sat, 17 Nov 2012 11:49:54 +0100
   Probably, this should be fixed somewhere in termp_it_pre(), not sure.
+  loc *  exist **  algo **  size *  imp **
 
 - .Nx 1.0a
   should be "NetBSD 1.0A", not "NetBSD 1.0a",
   see OpenBSD ccdconfig(8).
+  loc *  exist *  algo *  size *  imp **
 
 - 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).
+  loc *  exist ***  algo **  size *  imp **
 
 - When the -width string contains macros, the macros must be rendered
   before measuring the width, for example
@@ -363,17 +443,21 @@
   The same applies to .Bl -column column widths;
   reported again by Nicolas Joly Thu, 1 Mar 2012 13:41:26 +0100 via wiz@ 5 Mar
   reported again by Franco Fichtner Fri, 27 Sep 2013 21:02:28 +0200
+  loc ***  exist ***  algo ***  size **  imp ***
   An easy partial fix would be to just skip the first word if it starts
   with a dot, including any following white space, when measuring.
+  loc *  exist *  algo *  size *  imp ***
 
 - 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.
+  loc **  exist **  algo **  size *  imp **
 
 - 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
+  loc *  exist *  algo *  size *  imp *
 
 - trailing whitespace must be ignored even when followed by a font escape,
   see for example 
@@ -381,6 +465,7 @@
     \fBdig \fR
     operate in batch mode
   in dig(1).
+  loc **  exist **  algo **  size *  imp **
 
 ************************************************************************
 * warning issues
@@ -392,17 +477,21 @@
   to refer to fill mode, not literal mode
   See the mail from Werner LEMBERG on the groff list,
   Fri, 14 Feb 2014 18:54:42 +0100 (CET)
+  loc *  exist **  algo **  size *  imp **
 
 - warn about "new sentence, new line"
+  loc **  exist **  algo ***  size *  imp **
 
 - mandoc_special does not really check the escape sequence,
   but just the overall format
+  loc **  exist **  algo ***  size **  imp **
 
 - integrate mdoclint into mandoc ("end-of-line whitespace" thread)
   from jmc@  Mon, 13 Jul 2009 17:12:09 +0100
   from kristaps@  Mon, 13 Jul 2009 18:34:53 +0200
   from jmc@  Mon, 13 Jul 2009 17:45:37 +0059
   from kristaps@  Mon, 13 Jul 2009 19:02:03 +0200
+  (mostly done, check what remains)
 
 - -Tlint parser errors and warnings to stdout
   to tech@mdocml, naddy@  Wed, 28 Sep 2011 11:21:46 +0200
@@ -444,6 +533,7 @@ Several areas can be cleaned up to make mandoc even faster.  These are
 
 - instead of re-initialising the roff predefined-strings set before each
   parse, create a read-only version the first time and copy it 
+  loc *  exist **  algo **  size *  imp **
 
 ************************************************************************
 * structural issues