Issues with gendocs and images

[Akim Demaille]

Hi all!

A few images have been added to the Bison documentation
recently, and "make web-manual" faces a couple of issues.

First of all, I'd like to point out that tex is not called
in batch mode, I think it would be nice to pass --batch
to texi2dvi to avoid hanging on stdin.

The images come in several formats, so in the src tree I
have the (hand crafted) *.txt version, and there are *.pdf,
*.eps, and *.png available in the build tree (for PDF, DVI,
and HTML).

There is unfortunately no simple way to pass the corresponding
directories to the various tools.  texi2dvi (DVI and PDF) can
be taught easily via TEXINPUTS.  Yet for info, text, html,
there are several options to use (--info etc.).  Unfortunately
also, these flags do not accumulate, so '--info -Ifoo --info -Ibar'
will no do what one might expect.

Having a single -I option for gendocs would be most convenient!
And it should accumulate.

Besides, if the picture is not found by makeinfo, gendocs
exits with success.  That seems to come from makeinfo that treats
as a warning missing sources!

$ cat foo.texi
\input texinfo @c -*-texinfo-*-
@comment %**start of header

@center @image{figs/example-shift, 100pt}
@bye
$ LC_ALL=C makeinfo foo.texi
foo.texi:5: warning: @image file `figs/example-shift.txt' (for text) 
unreadable: No such file or directory.
$ echo $?
0
$ makeinfo --version
makeinfo (GNU texinfo) 4.13

Copyright (C) 2008 Free Software Foundation, Inc.
License GPLv3+: GNU GPL version 3 or later <http://gnu.org/licenses/gpl.html>
This is free software: you are free to change and redistribute it.
There is NO WARRANTY, to the extent permitted by law.

gendocs should probably check for this failure, and fail
at this point, instead of proceeding with a broken documentation.

Finally, but since the process ends before that point I
couldn't check by experience, I was wondering what needs
to be done to make sure that the HTML images will be part
of the html tarballs.

Thanks!