Re: [Groff] Better locale macro file handling?

[Colin Watson]

On Thu, Feb 19, 2009 at 12:11:15PM +0000, Colin Watson wrote:
> On Wed, Feb 18, 2009 at 08:10:24AM +0100, Werner LEMBERG wrote:
> > Colin Watson wrote:
> > > And, as you say, it is unfortunate from a backward compatibility
> > > point of view: man-db would probably end up having to detect the
> > > version of groff, since otherwise it would cause a warning on every
> > > single manual page unless the macro file is present (which will be
> > > the clear majority of pages).
> > 
> > Then use the `.warn' request directly.  If the `range' warning
> > (value 64) isn't set, `.warn' doesn't emit a warning if you supply a
> > value larger than WARN_TOTAL.
> 
> I hadn't thought of .warn; thanks. In that case simply feeding in this
> preamble will work:
> 
>   .warn (\n[.warn] - (\n[.warn] / 64 % 2 * 64))
>   .warn (\n[.warn] + 1048576 - (\n[.warn] / 1048576 % 2 * 1048576))

Of course this enables the new 'file' warning rather than disabling it;
which further reminds me that I forgot to enable WARN_FILE by default in
my previous patch. I've appended an updated patch to this mail.

That said: even with this, .warn alone doesn't help to avoid stderr spew
with older versions of groff. Since .mso currently emits an error, that
means old groff will still say:

  .warn (\n[.warn] - (\n[.warn] / 64 % 2 * 64))
  .warn (\n[.warn] - (\n[.warn] / 1048576 % 2 * 1048576))
  .mso foo.tmac
  <standard input>:3: can't find macro file `foo.tmac'

I think I need to do something like this instead (having discovered that
I can check groff's version at run-time):

  .if (\n[.g] & (\n[.x] > 1) & ((\n[.x] == 1) & (\n[.y] >= 20)) & ((\n[.x] == 
1) & (\n[.y] == 20) & (\n[.Y] >= 2))) \{
  .  warn (\n[.warn] - (\n[.warn] / 1048576 % 2 * 1048576))
  .  mso foo.tmac
  .\}


2009-02-19  Colin Watson  <address@hidden>

        Add a new `file' warning category.

        * src/roff/troff/troff.h (warning_type): Add WARN_FILE.
        * src/roff/troff/input.cpp (DEFAULT_WARNING_MASK): Include
        WARN_FILE.
        (macro_source): Convert error on missing macro file to a
        warning.
        * NEWS, doc/groff.texinfo (I/O, Warnings): Document new warning
        category.

=== modified file 'NEWS'
--- NEWS        2009-02-14 17:21:35 +0000
+++ NEWS        2009-02-19 16:52:02 +0000
@@ -20,6 +20,10 @@ o The new `lsm' request specifies a macr
   registers `lsn' and `lss' hold the number of removed leading spaces and
   the corresponding horizontal space, respectively.
 
+o There is a new warning category `file', enabled by default.  The `mso'
+  request emits warnings in this category when the requested macro file does
+  not exist.
+
 
 VERSION 1.20.1
 ==============

=== modified file 'doc/groff.texinfo'
--- doc/groff.texinfo   2009-02-14 17:21:35 +0000
+++ doc/groff.texinfo   2009-02-19 16:37:08 +0000
@@ -13122,6 +13122,8 @@ for the specified @var{file} in the same
 the the @option{-m} command line option.  If the file name to be
 included has the form @address@hidden and it isn't found,
 @code{mso} tries to include @address@hidden and vice versa.
+If the file does not exist, a warning of type @samp{file} is emitted.
address@hidden, for information about warnings.
 @endDefreq
 
 @DefreqList {trf, file}
@@ -14172,6 +14174,11 @@ conditions that are errors when they do 
 @itemx 524288
 Color related warnings.
 
address@hidden file
address@hidden 1048576
+Missing files.  The @code{mso} request gives this warning when the
+requested macro file does not exist.  This is enabled by default.
+
 @item all
 All warnings except @samp{di}, @samp{mac} and @samp{reg}.  It is
 intended that this covers all warnings that are useful with traditional

=== modified file 'src/roff/troff/input.cpp'
--- src/roff/troff/input.cpp    2009-02-14 17:21:35 +0000
+++ src/roff/troff/input.cpp    2009-02-19 16:37:30 +0000
@@ -59,7 +59,7 @@ extern "C" {
 #ifndef DEFAULT_WARNING_MASK
 // warnings that are enabled by default
 #define DEFAULT_WARNING_MASK \
-     (WARN_CHAR|WARN_NUMBER|WARN_BREAK|WARN_SPACE|WARN_FONT)
+     (WARN_CHAR|WARN_NUMBER|WARN_BREAK|WARN_SPACE|WARN_FONT|WARN_FILE)
 #endif
 
 // initial size of buffer for reading names; expanded as necessary
@@ -7367,7 +7367,7 @@ void macro_source()
       a_delete path;
     }
     else
-      error("can't find macro file `%1'", nm.contents());
+      warning(WARN_FILE, "can't find macro file `%1'", nm.contents());
     tok.next();
   }
 }

=== modified file 'src/roff/troff/troff.h'
--- src/roff/troff/troff.h      2009-01-05 20:10:29 +0000
+++ src/roff/troff/troff.h      2009-02-17 11:37:40 +0000
@@ -75,11 +75,12 @@ enum warning_type {
   WARN_SPACE = 0200000,
   WARN_FONT = 0400000,
   WARN_IG =  01000000,
-  WARN_COLOR = 02000000
+  WARN_COLOR = 02000000,
+  WARN_FILE = 04000000
   // change WARN_TOTAL if you add more warning types
 };
 
-const int WARN_TOTAL = 03777777;
+const int WARN_TOTAL = 07777777;
 
 int warning(warning_type, const char *,
            const errarg & = empty_errarg,

-- 
Colin Watson                                       address@hidden