bug#8640: 24.0.50; no pbm support on cygwin

bug#8640: 24.0.50; no pbm support on cygwin

[Katsumi Yamaoka]

Hi,

pbm image is not available in Emacs trunk built on cygwin at least
after May 6: (image-type-available-p 'pbm) => nil
Whereas png, jpeg, gif, xpm, etc. are all ok.  I guess this is due
to the recent changes in image.c.  Any hint?  Thanks.

In GNU Emacs 24.0.50.1 (i686-pc-cygwin, X toolkit, Xaw3d scroll bars)
 of 2011-05-09 on localhost
Windowing system distributor `The Cygwin/X Project', version 11.0.11000000
configured using `configure  '--verbose' '--with-x-toolkit=lucid''
[...]

bug#8640: 24.0.50; no pbm support on cygwin

[Juanma Barranquero]

> pbm image is not available in Emacs trunk built on cygwin at least
> after May 6: (image-type-available-p 'pbm) => nil
> Whereas png, jpeg, gif, xpm, etc. are all ok.

xbm is not available either. And of course is not cygwin-specific.

> I guess this is due
> to the recent changes in image.c.

Yes.

> Any hint?

More than a hint. I moved the library cache variable to w32 code,
turned CACHE_IMAGE_TYPE into a noop on non-Windows, and removed the
check on init-image-library. But I overlook the fact that the
predefined image types rely on being marked in the library cache as
available. That's because `image-type-available-p' always goes through
`init-image-library'.

Now, the fix is simple (the patch below fixes the problem), but we
should think whether it is cleaner to restore the library-cache to a
non-Windows specific code, or mark the only two predefined image types
in any other way, as the code below does. It's a bit ad-hoc, but
having the image types in the library cache, when they are not, in
fact, loaded from a library, is also a bit ugly.

Opinions and comments anyone?

    Juanma



=== modified file 'src/image.c'
--- src/image.c	2011-05-06 06:30:56 +0000
+++ src/image.c	2011-05-09 10:53:21 +0000
@@ -8602,6 +8602,11 @@
 of `dynamic-library-alist', which see).  */)
   (Lisp_Object type, Lisp_Object libraries)
 {
+
+  /* Types pbm and xbm are predefined and always available.  */
+  if (EQ (type, Qpbm) || EQ (type, Qxbm))
+    return Qt;
+
 #ifdef HAVE_NTGUI
   /* Don't try to reload the library.  */
   Lisp_Object tested = Fassq (type, Vlibrary_cache);

bug#8640: 24.0.50; no pbm support on cygwin

[Katsumi Yamaoka]

Juanma Barranquero wrote:
>> pbm image is not available in Emacs trunk built on cygwin at least
>> after May 6: (image-type-available-p 'pbm) => nil
>> Whereas png, jpeg, gif, xpm, etc. are all ok.

> xbm is not available either. And of course is not cygwin-specific.

Oh, that's bad.  I didn't verify it for xbm and other platforms.

>> I guess this is due
>> to the recent changes in image.c.

> Yes.

>> Any hint?

> More than a hint. I moved the library cache variable to w32 code,
> turned CACHE_IMAGE_TYPE into a noop on non-Windows, and removed the
> check on init-image-library. But I overlook the fact that the
> predefined image types rely on being marked in the library cache as
> available. That's because `image-type-available-p' always goes through
> `init-image-library'.

> Now, the fix is simple (the patch below fixes the problem), but we
> should think whether it is cleaner to restore the library-cache to a
> non-Windows specific code, or mark the only two predefined image types
> in any other way, as the code below does. It's a bit ad-hoc, but
> having the image types in the library cache, when they are not, in
> fact, loaded from a library, is also a bit ugly.

> Opinions and comments anyone?

The patch did the trick.  I hope it is installed even if it is
not smart.  It troubles at least Gnus users, since Gnus invokes
ImageMagick's `display' whenever an article contains X-Face (it
is the default behavior when pbm is unavailable). ;-)  Thanks.

bug#8640: 24.0.50; no pbm support on cygwin

[Juanma Barranquero]

On Tue, May 10, 2011 at 10:44, Katsumi Yamaoka <yamaoka@jpl.org> wrote:

> The patch did the trick.  I hope it is installed even if it is
> not smart.

I think it's the easiest and cleanest fix, so I've installed it
(slightly tweaked).

    Juanma