Re: display word wrapping

[Juanma Barranquero <jmbarranquero@wke.es>]

On 04 Jun 2004 14:45:30 +0200
storm@cua.dk (Kim F. Storm) wrote:

>>     (setq image-library-alist '(t))

> Just init it to t, and let init-image-libraries test for that special value.

OK.  init-image-libraries does proceed as usual if image-library-alist
is t (but it is responsability of the init_xxx_functions to get sure
that everything's OK if they use image-library-alist in any way).

> I'm sure you need Vimage_types internally, but I meant that you could
> drop exporting the Vimage_types to lisp.

It could be done easily, but, as you say, is useful for debugging.

> BTW, what happens if you compile emacs --without-x ?

I *think* (but I haven't tested it, I don't have a non-Windows
environment on which to try it) it should compile OK and just initialize
the built-in image types (xbm and pbm).

>         Fsignal (Qwrong_type_argument, Fcons (dlls, Qnil));

Ah, I see, thanks.  I've done instead

   wrong_type_argument (Qstringp, dlls);

so the message mentions that a string was expected.

Attached is the current iteration of the patch.  Could you (or anyone)
try it on non-Windows environments?

                                                                Juanma


--- lisp/term/w32-win.el.orig	2004-06-04 15:29:20.000000000 +0200
+++ lisp/term/w32-win.el	2004-06-04 02:15:48.000000000 +0200
@@ -1262,4 +1262,12 @@
 	    (error "Font not found")))))
 
+;;; Set default known names for image libraries
+(setq image-library-alist
+      '((xpm "libXpm-nox4.dll" "libxpm.dll")
+        (png "libpng13d.dll" "libpng13.dll" "libpng12d.dll" "libpng12.dll" "libpng.dll")
+        (jpeg "jpeg62.dll" "libjpeg.dll" "jpeg-62.dll" "jpeg.dll")
+        (tiff "libtiff3.dll" "libtiff.dll")
+        (gif "libungif.dll")))
+
 ;;; arch-tag: 69fb1701-28c2-4890-b351-3d1fe4b4f166
 ;;; w32-win.el ends here
--- lisp/image.el.orig	2004-06-04 15:28:50.000000000 +0200
+++ lisp/image.el	2004-06-04 15:19:33.000000000 +0200
@@ -49,4 +49,19 @@
 a non-nil value, TYPE is the image's type.")
 
+;;; 
+
+;;;###autoload
+(defvar image-library-alist t
+  "Alist of image types vs external libraries needed to display them.
+
+Each element is a list (IMAGE-TYPE LIBRARY...), where the car is a symbol
+representing a supported image type, and the rest are strings giving
+alternate filenames for the corresponding external libraries to load.
+They are tried in the order they appear on the list; if none of them can
+be loaded, the running session of Emacs won't display the image type.
+No entries are needed for pbm and xbm images; they're always supported.
+
+This variable is reset to nil each time its entries are processed.")
+;;;###autoload (put 'image-library-alist 'risky-local-variable t)
 
 (defun image-jpeg-p (data)
@@ -112,6 +127,7 @@
   "Value is non-nil if image type TYPE is available.
 Image types are symbols like `xbm' or `jpeg'."
-  (and (boundp 'image-types) (not (null (memq type image-types)))))
-
+  (prog1
+      (memq type (init-image-libraries image-library-alist))
+    (setq image-library-alist nil)))
 
 ;;;###autoload
--- src/image.c.orig	2004-06-04 15:27:59.000000000 +0200
+++ src/image.c	2004-06-04 15:12:20.000000000 +0200
@@ -646,11 +646,15 @@
      struct image_type *type;
 {
-  /* Make a copy of TYPE to avoid a bus error in a dumped Emacs.
-     The initialized data segment is read-only.  */
-  struct image_type *p = (struct image_type *) xmalloc (sizeof *p);
-  bcopy (type, p, sizeof *p);
-  p->next = image_types;
-  image_types = p;
-  Vimage_types = Fcons (*p->type, Vimage_types);
+  /* Protect against accidental redefinion.  */
+  if (NILP (Fmemq (*type->type, Vimage_types)))
+    {
+      /* Make a copy of TYPE to avoid a bus error in a dumped Emacs.
+         The initialized data segment is read-only.  */
+      struct image_type *p = (struct image_type *) xmalloc (sizeof *p);
+      bcopy (type, p, sizeof *p);
+      p->next = image_types;
+      image_types = p;
+      Vimage_types = Fcons (*p->type, Vimage_types);
+    }
 }
 
@@ -1789,4 +1793,30 @@
   }
 
+/* Load a DLL implementing an image type.
+   The `image-library-alist' variable associates a symbol,
+   identifying  an image type, to a list of possible filenames.
+   The function returns NULL if no library could be loaded for
+   the given image type, or if the library was previously loaded;
+   else the handle of the DLL.  */
+static HMODULE
+w32_dynaload (Lisp_Object libraries, Lisp_Object library_id)
+{
+  HMODULE library = NULL;
+
+  if (CONSP (libraries) && NILP (Fmemq (library_id, Vimage_types)))
+    {
+      Lisp_Object dlls = Fassq (library_id, libraries);
+
+      if (CONSP (dlls))
+        for (dlls = XCDR (dlls); !NILP (dlls); dlls = XCDR (dlls))
+          if (!CONSP (dlls) || !STRINGP (XCAR (dlls)))
+            wrong_type_argument (Qstringp, dlls);
+          else if (library = LoadLibrary (SDATA (XCAR (dlls))))
+            break;
+    }
+
+  return library;
+}
+
 #endif /* HAVE_NTGUI */
 
@@ -3489,11 +3518,10 @@
 DEF_IMGLIB_FN (XImageFree);
 
-
 static int
-init_xpm_functions (void)
+init_xpm_functions (Lisp_Object libraries)
 {
   HMODULE library;
 
-  if (!(library = LoadLibrary ("libXpm.dll")))
+  if (!(library = w32_dynaload (libraries, Qxpm)))
     return 0;
 
@@ -5589,19 +5617,10 @@
 
 static int
-init_png_functions (void)
+init_png_functions (Lisp_Object libraries)
 {
   HMODULE library;
 
-  /* Ensure zlib is loaded.  Try debug version first.  */
-  if (!LoadLibrary ("zlibd.dll")
-      && !LoadLibrary ("zlib.dll"))
-    return 0;
-
   /* Try loading libpng under probable names.  */
-  if (!(library = LoadLibrary ("libpng13d.dll"))
-      && !(library = LoadLibrary ("libpng13.dll"))
-      && !(library = LoadLibrary ("libpng12d.dll"))
-      && !(library = LoadLibrary ("libpng12.dll"))
-      && !(library = LoadLibrary ("libpng.dll")))
+  if (!(library = w32_dynaload (libraries, Qpng)))
     return 0;
 
@@ -6247,11 +6266,9 @@
 
 static int
-init_jpeg_functions (void)
+init_jpeg_functions (Lisp_Object libraries)
 {
   HMODULE library;
 
-  if (!(library = LoadLibrary ("libjpeg.dll"))
-      && !(library = LoadLibrary ("jpeg-62.dll"))
-      && !(library = LoadLibrary ("jpeg.dll")))
+  if (!(library = w32_dynaload (libraries, Qjpeg)))
     return 0;
 
@@ -6684,9 +6701,9 @@
 
 static int
-init_tiff_functions (void)
+init_tiff_functions (Lisp_Object libraries)
 {
   HMODULE library;
 
-  if (!(library = LoadLibrary ("libtiff.dll")))
+  if (!(library = w32_dynaload (libraries, Qtiff)))
     return 0;
 
@@ -7104,9 +7121,9 @@
 
 static int
-init_gif_functions (void)
+init_gif_functions (Lisp_Object libraries)
 {
   HMODULE library;
 
-  if (!(library = LoadLibrary ("libungif.dll")))
+  if (!(library = w32_dynaload (libraries, Qgif)))
     return 0;
 
@@ -7881,4 +7898,63 @@
  ***********************************************************************/
 
+#ifdef HAVE_NTGUI
+/* Image types that rely on external libraries are loaded dynamically
+   if the library is available.  */
+#define IF_LIB_AVAILABLE(init_lib_fn)  if (init_lib_fn (libraries))
+#else
+#define IF_LIB_AVAILABLE(init_func)    /* Load unconditionally */
+#endif /* HAVE_NTGUI */
+
+DEFUN ("init-image-libraries", Finit_image_libraries, Sinit_image_libraries, 1, 1, 0,
+       doc: /* Initialize image libraries.
+Image types pbm and xbm are prebuilt; other types are loaded here.
+Which libraries are loaded depends on LIBRARIES (usually, the value
+of `image-library-alist'.  */)
+     (libraries)
+{
+  if (EQ (libraries, Qt) || !NILP (libraries))
+    {
+
+#if defined (HAVE_XPM) || defined (MAC_OS)
+      IF_LIB_AVAILABLE(init_xpm_functions)
+        define_image_type (&xpm_type);
+#endif
+
+#if defined (HAVE_JPEG) || defined (MAC_OS)
+      IF_LIB_AVAILABLE(init_jpeg_functions)
+        define_image_type (&jpeg_type);
+#endif
+
+#if defined (HAVE_TIFF) || defined (MAC_OS)
+      IF_LIB_AVAILABLE(init_tiff_functions)
+        define_image_type (&tiff_type);
+#endif
+
+#if defined (HAVE_GIF) || defined (MAC_OS)
+      IF_LIB_AVAILABLE(init_gif_functions)
+        define_image_type (&gif_type);
+#endif
+
+#if defined (HAVE_PNG) || defined (MAC_OS)
+      IF_LIB_AVAILABLE(init_png_functions)
+        define_image_type (&png_type);
+#endif
+
+#ifdef HAVE_GHOSTSCRIPT
+      define_image_type (&gs_type);
+#endif
+
+#ifdef MAC_OS
+      /* Animated gifs use QuickTime Movie Toolbox.  So initialize it here. */
+      EnterMovies ();
+#ifdef MAC_OSX
+      init_image_func_pointer ();
+#endif
+#endif
+    }
+
+  return Vimage_types;
+}
+
 void
 syms_of_image ()
@@ -7958,4 +8034,5 @@
 #endif
 
+  defsubr (&Sinit_image_libraries);
   defsubr (&Sclear_image_cache);
   defsubr (&Simage_size);
@@ -7985,13 +8062,4 @@
 }
 
-
-#ifdef HAVE_NTGUI
-/* Image types that rely on external libraries are loaded dynamically
-   if the library is available.  */
-#define IF_LIB_AVAILABLE(init_lib_fn)  if (init_lib_fn())
-#else
-#define IF_LIB_AVAILABLE(init_func)    /* Load unconditionally */
-#endif /* HAVE_NTGUI */
-
 void
 init_image ()
@@ -8002,41 +8070,4 @@
   define_image_type (&xbm_type);
   define_image_type (&pbm_type);
-
-#if defined (HAVE_XPM) || defined (MAC_OS)
-  IF_LIB_AVAILABLE(init_xpm_functions)
-    define_image_type (&xpm_type);
-#endif
-
-#if defined (HAVE_JPEG) || defined (MAC_OS)
-  IF_LIB_AVAILABLE(init_jpeg_functions)
-    define_image_type (&jpeg_type);
-#endif
-
-#if defined (HAVE_TIFF) || defined (MAC_OS)
-  IF_LIB_AVAILABLE(init_tiff_functions)
-    define_image_type (&tiff_type);
-#endif
-
-#if defined (HAVE_GIF) || defined (MAC_OS)
-  IF_LIB_AVAILABLE(init_gif_functions)
-    define_image_type (&gif_type);
-#endif
-
-#if defined (HAVE_PNG) || defined (MAC_OS)
-  IF_LIB_AVAILABLE(init_png_functions)
-    define_image_type (&png_type);
-#endif
-
-#ifdef HAVE_GHOSTSCRIPT
-  define_image_type (&gs_type);
-#endif
-
-#ifdef MAC_OS
-  /* Animated gifs use QuickTime Movie Toolbox.  So initialize it here. */
-  EnterMovies ();
-#ifdef MAC_OSX
-  init_image_func_pointer ();
-#endif
-#endif
 }