New approach to backend registers

luametalatex-back-pdf.lua

@@ -143,10 +143,9 @@ callback.register("stop_run", function()
   texio.write_nl(string.format("Transcript written on %s.\n", status.log_name))
 end, "Finish PDF file")
 token.luacmd("pdfvariable", function()
-  for n, t in pairs(pdf.variable_tokens) do
+  for _, n in ipairs(pdf.variable_names) do
     if token.scan_keyword(n) then
-      token.put_next(t)
-      return
+      return token.put_next(token.create('pdfvariable  ' .. n))
     end
   end
   -- The following error message gobbles the next word as a side effect.

luametalatex-baseregisters.lua

@@ -0,0 +1,99 @@
+local value_values = token.values'value'
+for i=0,#value_values do
+  value_values[value_values[i]] = i
+end
+local count_code = value_values.integer
+local dimen_code = value_values.dimension
+
+local set_local = require'luametalatex-local'
+
+local texmeta = getmetatable(tex)
+local texmetaoldindex = texmeta.__index
+local texmetaoldnewindex = texmeta.__newindex
+
+local tex_variables = {}
+
+function texmeta.__index(t, k)
+  return tex_variables[k] or texmetaoldindex(t, k)
+end
+function texmeta.__newindex(t, k, v)
+  if tex_variables[k] then
+    return set_local(tex_variables, k, v)
+  else
+    return texmetaoldnewindex(t, k, v)
+  end
+end
+
+local function tex_variable(value, scanner, name, default)
+  token.luacmd(name, function(_, scanning)
+    if scanning == 'value' then
+      return value, tex_variables[name]
+    else
+      token.scan_keyword'='
+      return set_local(tex_variables, name, scanner(), scanning == 'global')
+    end
+  end, 'global', 'protected', 'value')
+  tex_variables[name] = default
+end
+
+local real_pdf_variables, pdf_variable_names = {}, {'pageresources'}
+local pdf_toks = {}
+local pdf_variables = setmetatable(pdf.variable, {
+  __index = function(_, k)
+    local v = real_pdf_variables[k]
+    if v then return v end
+    v = pdf_toks[k]
+    if v then
+      return tex.toks[v]
+    end
+  end,
+  __newindex = function(_, k, v)
+    if real_pdf_variables[k] then
+      return set_local(real_pdf_variables, k, v)
+    end
+    local toks = pdf_toks[k]
+    if toks then
+      tex.toks[toks] = v
+    end
+  end,
+})
+pdf.variable_names = pdf_variable_names
+
+local function pdf_variable(value, scanner, name, default)
+  pdf_variable_names[#pdf_variable_names+1] = name
+  token.luacmd('pdfvariable  ' .. name, function(_, scanning)
+    if scanning == 'value' then
+      return value, real_pdf_variables[name]
+    else
+      token.scan_keyword'='
+      return set_local(real_pdf_variables, name, scanner(), scanning == 'global')
+    end
+  end, 'global', 'protected', 'value')
+  real_pdf_variables[name] = default
+end
+
+tex_variable(count_code, token.scan_int, 'suppressfontnotfounderror', 0)
+tex_variable(count_code, token.scan_int, 'outputmode', 1) -- The "traditional" default would be 0,
+                                                            -- but we do not actually support that.
+tex_variable(dimen_code, token.scan_dimen, 'pageheight', tex.sp'297mm')
+tex_variable(dimen_code, token.scan_dimen, 'pagewidth', tex.sp'210mm')
+
+tex_variable(count_code, token.scan_int, 'bodydirection', 0)
+tex_variable(count_code, token.scan_int, 'pagedirection', 0)
+
+pdf_variable(dimen_code, token.scan_dimen, 'horigin', tex.sp'1in')
+pdf_variable(dimen_code, token.scan_dimen, 'vorigin', tex.sp'1in')
+pdf_variable(dimen_code, token.scan_dimen, 'linkmargin', tex.sp'0pt')
+pdf_variable(count_code, token.scan_int, 'majorversion', 1)
+pdf_variable(count_code, token.scan_int, 'minorversion', 7)
+pdf_variable(count_code, token.scan_int, 'compresslevel', 0)
+pdf_variable(count_code, token.scan_int, 'objcompresslevel', 0) -- 0 is actually the only supported value right now, so this is basically ignored
+
+function tex.getbodydir() return tex.bodydirection end
+function tex.getpagedir() return tex.pagedirection end
+function tex.setbodydir(i) tex.bodydirection = i end
+function tex.setpagedir(i) tex.pagedirection = i end
+local dir_regs = require 'luametalatex-dir-registers'
+dir_regs 'textdir'
+dir_regs 'bodydir'
+dir_regs 'pagedir'

luametalatex-baseregisters.tex

@@ -1,124 +0,0 @@
-\begingroup
-\catcode`\^^^^fffe=11
-\catcode`\@=11
-\toks0{%
-  do
-  local function frozen(s)
-    local t = token.create(s)
-    return t
-    % print(t, token.new(t.mode, t.command), t.mode, t.command, t.data, t.cmdchrcs)
-    % return token.new(t.mode, t.command)
-  end
-  local dimen_cmd = token.command_id'register_dimen'
-  local count_cmd = token.command_id'register_int'
-  local toks_cmd = token.command_id'register_toks'
-  local tex_params = {}
-  local texmeta = getmetatable(tex)
-  local texmetaoldindex = texmeta.__index
-  local texmetaoldnewindex = texmeta.__newindex
-  function texmeta.__index(t, k)
-    local v = tex_params[k]
-    if v then
-      if v.command == count_cmd then
-        return tex.count[v.index]
-      elseif v.command == dimen_cmd then
-        return tex.dimen[v.index]
-      elseif v.command == toks_cmd then
-        return tex.toks[v.index]
-      end
-    else
-      return texmetaoldindex(t, k)
-    end
-  end
-  function texmeta.__newindex(t, k, v)
-    local p = tex_params[k]
-    if p then
-      if p.command == count_cmd then
-        tex.count[p.index] = v
-      elseif p.command == dimen_cmd then
-        tex.dimen[p.index] = v
-      elseif p.command == toks_cmd then
-        tex.toks[p.index] = v
-      end
-    else
-      return texmetaoldnewindex(t, k, v)
-    end
-  end
-  local pdf_params = {}
-  pdf.variable_tokens = pdf_params
-  setmetatable(pdf.variable, {
-    __index = function(t, k)
-      local v = pdf_params[k]
-      if v then
-        if v.command == count_cmd then
-          return tex.count[v.index]
-        elseif v.command == dimen_cmd then
-          return tex.dimen[v.index]
-        elseif v.command == toks_cmd then
-          return tex.toks[v.index]
-        end
-      end
-    end,
-    __newindex = function(t, k, v)
-      local p = pdf_params[k]
-      if p then
-        if p.command == count_cmd then
-          tex.count[p.index] = v
-        elseif p.command == dimen_cmd then
-          tex.dimen[p.index] = v
-        elseif p.command == toks_cmd then
-          tex.toks[p.index] = v
-        end
-      else
-        return rawset(t, k, v)
-      end
-    end,
-  })
-}
-\def\InternalAlloc#1#2#3#4#5{%
-  \csname new#3\endcsname#1%
-  \global#1=#5\relax
-  \etoksapp0{#2_params["\luaescapestring{#4}"] = frozen"\luaescapestring{\csstring#1}"}
-}
-\def\internalAlloc#1#2#3{%
-  \expandafter\InternalAlloc\csname ^^^^fffe#3@#1\endcsname{#1}{#2}{#3}%
-}
-\def\texAlloc#1#2{%
-  \expandafter\InternalAlloc\csname #2\endcsname{tex}{#1}{#2}%
-}
-\def\pdfAlloc{%
-  \internalAlloc{pdf}%
-}
-\texAlloc{count}{suppressfontnotfounderror}{0}
-\texAlloc{count}{outputmode}{1} % The "traditional" default would be 0,
-                                % but we do not actually support that.
-\texAlloc{dimen}{pageheight}{297mm}
-\texAlloc{dimen}{pagewidth}{210mm}
-\pdfAlloc{dimen}{horigin}{1in}
-\pdfAlloc{dimen}{vorigin}{1in}
-\pdfAlloc{dimen}{linkmargin}{0pt}
-\pdfAlloc{count}{majorversion}{1}
-\pdfAlloc{count}{minorversion}{7}
-\pdfAlloc{count}{compresslevel}{0}
-\pdfAlloc{count}{objcompresslevel}{0} % 0 is actually the only supported value right now, so this is basically ignored
-\pdfAlloc{toks}{pageresources}{{}}
-
-\texAlloc{count}{bodydirection}{0}
-\texAlloc{count}{pagedirection}{0}
-\etoksapp0{
-  function tex.getbodydir() return tex.bodydirection end
-  function tex.getpagedir() return tex.pagedirection end
-  function tex.setbodydir(i) tex.bodydirection = i end
-  function tex.setpagedir(i) tex.pagedirection = i end
-  local dir_regs = require 'luametalatex-dir-registers'
-  dir_regs 'textdir'
-  dir_regs 'bodydir'
-  dir_regs 'pagedir'
-  end
-}
-
-\directlua{
-  lua.prepared_code[\csstring#lua.prepared_code+1] = tex.toks[0]
-  \the\toks0
-}
-\endgroup

luametalatex-dir-registers.lua

@@ -11,16 +11,13 @@ function tex.gettextdir() return tex.textdirection end
 function tex.getlinedir() return tex.linedirection end
 function tex.getmathdir() return tex.mathdirection end
 function tex.getpardir()  return tex.pardirection  end
--- local integer_code = value_values.none
 local integer_code = value_values.integer
-local functions = lua.get_functions_table()
-local lua_call_cmd = token.command_id'lua_call'
 local function set_xdir(id, scanning)
-  -- local name = names[id]
-  if scanning then
+  if scanning == 'value' then
+    print(scanning)
     return integer_code, getters[id]()
-    -- return integer_code, tex[name .. 'ection']
   end
+  -- local global = scanning == 'global'
   local value
   if token.scan_keyword'tlt' then
     value = 0
@@ -30,7 +27,6 @@ local function set_xdir(id, scanning)
     value = token.scan_int()
   end
   setters[id](value)
-  -- tex["set" .. name](value)
 end
 return function(name)
   local getter = tex["get" .. name]

luametalatex-firstcode.lua

@@ -12,7 +12,7 @@ local set_lua = token.set_lua
 -- probably doesn't store the function in the array part of the Lua table.
 -- Let's reconsider if this ever becomes a problem.
 -- local new_luafunction = luatexbase.new_luafunction
-local predefined_luafunctions = status.ini_version and 65535 -- 1<<16 - 1 -- We start with 1<<16
+local predefined_luafunctions = status.ini_version and 65536 -- 1<<16  -- We start with 1<<16 + 1 (1<<16=65536 is reserved for luametalatex-local)
 local function new_luafunction(name)
   if predefined_luafunctions then
     predefined_luafunctions = predefined_luafunctions + 1
@@ -221,6 +221,7 @@ else
     -- fixupluafunctions = nil
   -- end
 end
+require'luametalatex-baseregisters'
 require'luametalatex-back-pdf'
 require'luametalatex-node-luaotfload'
 

luametalatex-local.lua

@@ -0,0 +1,53 @@
+-- Implement support for local variables.
+
+local stack = {}
+
+local restore_func = 65536 -- Reserved in firstcode
+lua.get_functions_table()[restore_func] = function()
+  local level = assert(stack[tex.currentgrouplevel], 'Out of sync')
+  stack[tex.currentgrouplevel] = nil
+  for t,entries in next, level do
+    for k,v in next, entries do
+      t[k] = v
+    end
+  end
+end
+local lua_call = token.command_id'lua_call'
+local restore_toks = {token.create'atendofgroup', token.new(restore_func, lua_call)}
+local put_next = token.put_next
+local runtoks = tex.runtoks
+local function put_restore_toks()
+  put_next(restore_toks)
+end
+
+return function(t, k, v, global)
+  local l = tex.currentgrouplevel
+  if global then
+    for i=1,l do
+      local level = stack[i]
+      if level then
+        local saved = level[t]
+        if saved then
+          saved[k] = nil
+        end
+      end
+    end
+  elseif l > 0 then
+    local level = stack[l]
+    if not level then
+      level = {}
+      runtoks(put_restore_toks)
+      stack[l] = level
+    end
+
+    local saved = level[t]
+    if not saved then
+      saved = {}
+      level[t] = saved
+    end
+
+    saved[k] = saved[k] or t[k]
+  end
+
+  t[k] = v
+end

luametalatex-ltexpl-hook.tex

@@ -1,5 +1,6 @@
 \directlua{unhook_expl()}
-\input luametalatex-baseregisters
+% See baseregisters for list of toks pdfvariables
+\expandafter\newtoks\csname pdfvariable \space pageresources\endcsname
 \ifx\@tfor\undefined
   \def\@tfor#1\do#2{}
 \fi

luametalatex-pdf-escape.lua

@@ -1,4 +1,4 @@
-local mode = 6
+local mode = 0
 -- Control how much escaping is done... the mode is a bitset:
 -- Bit 0: Disable auto-detection of pre-escaped input
 -- Bit 1: Convert UTF-8 input to UTF-16

luametaplain.ini

@@ -17,5 +17,5 @@
 \endgroup
 \input load-unicode-data.tex
 \input etex.src
-\input luametalatex-baseregisters
+\expandafter\newtoks\csname pdfvariable \space pageresources\endcsname
 \dump