replace glyph list loader

Karl Berry made us aware that our generated version of ``font-age.lua``
differs from the Context/Luatex-Fonts one and should be renamed. It’s
trivial to do so but invasive still. This workaround may have to be
adapted if Hans chooses to rewrite the Glyph List loader.

1 files changed, 49 insertions, 1 deletions

diff --git a/luaotfload-override.lua b/luaotfload-override.lua
index 863187f..c047dad 100644
--- a/luaotfload-override.lua
+++ b/luaotfload-override.lua
@@ -63,7 +63,7 @@ end
 
 local level_ids = { common  = 0, loading = 1, search  = 2 }
 
-logs.names_report = function (mode, lvl, ...)
+local names_report = function (mode, lvl, ...)
     if type(lvl) == "string" then
         lvl = level_ids[lvl]
     end
@@ -81,4 +81,52 @@ logs.names_report = function (mode, lvl, ...)
     end
 end
 
+logs.names_report = names_report
+
+--[[doc--
+
+    Adobe Glyph List.
+    -------------------------------------------------------------------
+
+    Context provides a somewhat different font-age.lua from an unclear
+    origin. Unfortunately, the file name it reads from is hard-coded
+    in font-enc.lua, so we have to replace the entire table.
+
+    This shouldn’t cause any complications. Due to its implementation
+    the glyph list will be loaded upon loading a OTF or TTF for the
+    first time during a TeX run. (If one sticks to TFM/OFM then it is
+    never read at all.) For this reason we can install a metatable that
+    looks up the file of our choosing and only falls back to the
+    Context one in case it cannot be found.
+
+--doc]]--
+
+if next(fonts.encodings.agl) then
+    print(next, fonts.encodings.agl)
+    --- unnecessary because the file shouldn’t be loaded at this time
+    --- but we’re just making sure
+    fonts.encodings.agl = nil
+    collectgarbage"collect"
+end
+
+
+fonts.encodings.agl = { }
+
+setmetatable(fonts.encodings.agl, { __index = function (t, k)
+    if k == "unicodes" then
+        local glyphlist = resolvers.findfile"luaotfload-glyphlist.lua"
+        if glyphlist then
+            names_report("both", 0, "load", "loading the Adobe glyph list")
+        else
+            glyphlist = resolvers.findfile"font-age.lua"
+            names_report("both", 0, "load", "loading the extended glyph list from ConTeXt")
+        end
+        local unicodes      = dofile(glyphlist)
+        fonts.encodings.agl = { unicodes = unicodes }
+        return unicodes
+    else
+        return nil
+    end
+end })
+
 -- vim:tw=71:sw=4:ts=4:expandtab