Bug in .C2 macro, and patch for unicode box drawing

[Roger Leigh]

Dear groff maintainers,

[I'm not subscribed to the list, so a CC on any reply would be
appreciated]

GROFF VERSION: 1.20.1
MACHINE:       amd64 generic
OS:            Debian GNU/Linux
COMPILER:      GCC 4.3.2
INPUT FILES:   groff_char-box.man (attached)
COMMAND LINE:  groff -Tutf8 -man groff_char-box.man > groff_char-box.utf8
               (groff_char-box.man and groff_char-box.utf8 are attached)

DESCRIPTION OF INCORRECT BEHAVIOUR:

Many UCS codepoints fail to display.

A general trend is that all codepoints ending (or containing?) A-F
completely fail to display.  Is the .C2 macro not handling hexadecimal
input correctly?  Does it only work if you use 0-9 rather than 0-F?

Additionally, some codepoints fail to display even though their numbers
are only using 0-9.

The complete list of codepoints failing is:

2500 2501 2502 2503 2504 2505 250a 250b 250c 250d 250e 250f 251a 251b
251c 251d 251e 251f 252a 252b 252c 252d 252e 252f 253a 253b 253c 253d
253e 253f 254a 254b 254c 254d 254e 254f 255a 255b 255c 255d 255e 255f
256a 256b 256c 256d 256e 256f 257a 257b 257c 257d 257e 257f 258a 258b
258c 258d 258e 258f 259a 259b 259c 259d 259e 259f 25a0 25a1 25a2 25a3
25a4 25a5 25a6 25a7 25a8 25a9 25aa 25ab 25ac 25ad 25ae 25af 25b0 25b1
25b2 25b3 25b4 25b5 25b6 25b7 25b8 25b9 25ba 25bb 25bc 25bd 25be 25bf
25c0 25c1 25c2 25c3 25c4 25c5 25c6 25c7 25c8 25c9 25ca 25cb 25cc 25cd
25ce 25cf 25d0 25d1 25d2 25d3 25d4 25d5 25d6 25d7 25d8 25d9 25da 25db
25dc 25dd 25de 25df 25e0 25e1 25e2 25e3 25e4 25e5 25e6 25e7 25e8 25e9
25ea 25eb 25ec 25ed 25ee 25ef 25f0 25f1 25f2 25f3 25f4 25f5 25f6 25f7
25f8 25f9 25fa 25fb 25fc 25fd 25fe 25ff

SUGGESTED FIX:

If I use the .C2 macro as used on other lines in groff_char, I would
expect groff to display the glyph.  The glyphs all display perfectly
well on my terminal, so I would expect groff to pass them through
correctly.  There may be two issues, firstly the fact that codepoints
containing/ending in A-F are not displayed at all; secondly that
others containing only 0-9 do not display for some ranges.

I'm afraid I'm not familiar with the new unicode support in groff, so
I don't have a good suggestion as to the cause.  Does every codepoint
need listing in the font description (I'm looking at font/devutf8/R*)
or can groff use wcwidth() for formatting decisions for missing glyphs?


I have also provided a patch to man/groff_char.man to add Unicode
box-drawing, block elements and geometric shapes to groff_char.  Please
feel free to apply it--I find it useful for myself (except for those
glyphs that don't display!).  I assigned all current and future
copyrights on my groff work to the FSF in 2003, so it's all OK from
that POV.

This is also recorded as Debian bug #541688
http://bugs.debian.org/cgi-bin/bugreport.cgi?bug=541688


Regards,
Roger

-- 
  .''`.  Roger Leigh
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groff_char-box.man
Description: Unix manual page

groff_char-box.utf8
Description: Text document

groff_char.man-unicode-box-drawing.patch
Description: Text Data