1 files changed, 90 insertions, 0 deletions
diff --git a/tex/context/base/font-chk.lua b/tex/context/base/font-chk.lua
new file mode 100644
index 000000000..32fdf8894
--- /dev/null
+++ b/tex/context/base/font-chk.lua
@@ -0,0 +1,90 @@
+if not modules then modules = { } end modules ['font-chk'] = {
+    version   = 1.001,
+    comment   = "companion to font-ini.mkiv",
+    author    = "Hans Hagen, PRAGMA-ADE, Hasselt NL",
+    copyright = "PRAGMA ADE / ConTeXt Development Team",
+    license   = "see context related readme files"
+}
+
+-- possible optimization: delayed initialization of vectors
+
+fonts              = fonts or { }
+fonts.checkers     = fonts.checkers or { }
+
+local checkers     = fonts.checkers
+local fontdata     = fonts.ids
+local is_character = characters.is_character
+local chardata     = characters.data
+
+local glyph        = node.id('glyph')
+local traverse_id  = node.traverse_id
+local remove_node  = nodes.remove
+
+-- maybe in fonts namespace
+-- deletion can be option
+
+checkers.enabled = false
+checkers.delete  = false
+
+function fonts.register_message(font,char,message)
+    local tfmdata = fontdata[font]
+    local shared = tfmdata.shared
+    local messages = shared.messages
+    if not messages then
+        messages = { }
+        shared.messages = messages
+    end
+    local category = messages[message]
+    if not category then
+        category = { }
+        messages[message] = category
+    end
+    if not category[char] then
+        logs.report("fonts","char U+%04X in font '%s' with id %s: %s",char,tfmdata.fullname,font,message)
+        category[char] = true
+    end
+end
+
+function checkers.missing(head)
+    if checkers.enabled then
+        local lastfont, characters, found = nil, nil, nil
+        for n in traverse_id(glyph,head) do
+            local font, char = n.font, n.char
+            if font ~= lastfont then
+                characters = fontdata[font].characters
+            end
+            if not characters[char] and is_character[chardata[char].category] then
+                if checkers.delete then
+                    fonts.register_message(font,char,"missing (will be deleted)")
+                else
+                    fonts.register_message(font,char,"missing")
+                end
+                if not found then
+                    found = { n }
+                else
+                    found[#found+1] = n
+                end
+            end
+        end
+        if found and checkers.delete then
+            for i=1,#found do
+                head = remove_node(head,found[i],true)
+            end
+        end
+    end
+    return head, false
+end
+
+trackers.register("fonts.missing", function(v)
+    tasks.enableaction("processors", "fonts.checkers.missing") -- always on then
+    checkers.enabled = v
+end)
+
+function checkers.enable(delete)
+    tasks.enableaction("processors", "fonts.checkers.missing") -- always on then
+    if delete ~= nil then
+        checkers.delete = delete
+   end
+   checkers.enabled = true
+end
+