-----------------------------------------------------------------------
-- FILE: luaotfload-loaders.lua
-- DESCRIPTION: Luaotfload callback handling
-- REQUIREMENTS: luatex v.0.80 or later; package lualibs
-- AUTHOR: Philipp Gesang <phg@phi-gamma.net>
-- AUTHOR: Hans Hagen, Khaled Hosny, Elie Roux, David Carlisle
-----------------------------------------------------------------------
assert(luaotfload_module, "This is a part of luaotfload and should not be loaded independently") {
name = "luaotfload-loaders",
version = "3.29", --TAGVERSION
date = "2024-12-03", --TAGDATE
description = "luaotfload submodule / callback handling",
license = "GPL v2.0"
}
-----------------------------------------------------------------------
if not lualibs then error "this module requires Luaotfload" end
if not luaotfload then error "this module requires Luaotfload" end
local logreport = luaotfload.log and luaotfload.log.report or print
local function lua_reader (specification)
local fullname = specification.resolved
if fullname then
local loader = loadfile (fullname)
loader = loader and loader ()
return loader and loader (specification)
end
end
local function eval_reader (specification)
local eval = specification.eval
if not eval or type (eval) ~= "function" then return nil end
logreport ("both", 0, "loaders",
"eval: found tfmdata for %q, injecting.",
specification.name)
return eval ()
end
local function unsupported_reader (format)
return function (specification)
logreport ("both", 4, "loaders",
"font format %q unsupported; cannot load %s.",
format, tostring (specification.name))
end
end
local type1_reader = fonts.readers.afm
local tfm_reader = fonts.readers.tfm
local function install_formats ()
local fonts = fonts
if not fonts then return false end
local readers = fonts.readers
local sequence = readers.sequence
local seqset = table.tohash (sequence)
local formats = fonts.formats
if not readers or not formats then return false end
local function aux (which, reader)
if not which or type (which) ~= "string"
or not reader or type (reader) ~= "function" then
logreport ("both", 2, "loaders", "Error installing reader for %q.", which)
return false
end
formats [which] = "type1"
readers [which] = reader
if not seqset [which] then
logreport ("both", 3, "loaders",
"Extending reader sequence for %q.", which)
sequence [#sequence + 1] = which
seqset [which] = true
end
return true
end
return aux ("evl", eval_reader)
and aux ("lua", lua_reader)
and aux ("pfa", unsupported_reader "pfa")
and aux ("afm", type1_reader)
and aux ("pfb", type1_reader)
and aux ("tfm", tfm_reader)
and aux ("ofm", tfm_reader)
and aux ("dfont", unsupported_reader "dfont")
end
local function not_found_msg (specification, size, id)
logreport ("both", 0, "loaders", "")
logreport ("both", 0, "loaders",
"--------------------------------------------------------")
logreport ("both", 0, "loaders", "")
logreport ("both", 0, "loaders", "Font definition failed for:")
logreport ("both", 0, "loaders", "")
logreport ("both", 0, "loaders", " > id : %d", id)
logreport ("both", 0, "loaders", " > specification : %q", specification)
if size > 0 then
logreport ("both", 0, "loaders", " > size : %.2f pt", size / 2^16)
end
logreport ("both", 0, "loaders", "")
logreport ("both", 0, "loaders",
"--------------------------------------------------------")
end
local definers --- (string, spec -> size -> id -> tmfdata) hash_t
do
local hashed_cache = {}
local fontdata_cache = fonts.hashes.identifiers
local function register(fontdata, id)
if fontdata and id then
local hash = fontdata.properties.hash
if not hash then
logreport('both', 2, 'loaders', "Registering font %s with id %s with missing hash.", id, fontdata.properties.filename or "unknown")
elseif not hashed_cache[hash] then
hashed_cache[hash] = id
logreport('both', 4, 'loaders', "Registering font %s with id %s and hash %s.", id, fontdata.properties.filename or "unknown", hash)
end
fontdata_cache[id] = fontdata
end
end
function registered(hash)
local id = hashed_cache[hash]
return id, fontdata_cache[id]
end
fonts.definers.register = register
fonts.definers.registered = registered
local extra_hash_funcs = {}
local function ltx_read(spec, size, id)
spec = type(spec) == 'string' and fonts.definers.analyze(spec, size) or spec
spec = fonts.definers.resolve(spec)
local hash = fonts.constructors.hashinstance(spec)
-- extra_hash_func allows the loader to determine additional hash parts
-- depending on the actual font. This is used e.g. for variable fonts which
-- should be hashed based on their designsize / modifiers too.
local extra_hash_func = extra_hash_funcs[hash]
if extra_hash_func then
hash = hash .. ' @ ' .. table.join(extra_hash_func(spec), ' @ ')
end
local cached = registered(hash)
if cached then return cached end -- already loaded
local fontdata = fonts.definers.loadfont(spec)
if not fontdata then
logreport('both', 2, 'loaders', 'Failed to load font ' .. spec.name)
return
end
-- If extra_hash_func was already set then the hash is already extended.
-- Otherwise we have to do it now if requested.
if not extra_hash_func then
extra_hash_func = fontdata.properties.extra_hash_func
if extra_hash_func then
hash = hash .. ' @ ' .. table.join(extra_hash_func(spec), ' @ ')
end
end
fontdata.properties.hash = hash
register(fontdata, id)
return fontdata
end
local function read(specification, size, id)
local fontdata = ltx_read(specification, size, id)
if not fontdata or id or tonumber(fontdata) then
return fontdata
end
id = font.define(fontdata)
register(fontdata, id)
return id
end
local function patch (specification, size, id)
local fontdata = ltx_read (specification, size, id)
----if not fontdata then not_found_msg (specification, size, id) end
if type (fontdata) == "table" and fontdata.encodingbytes == 2 then
--- We need to test for `encodingbytes` to avoid passing
--- tfm fonts to `patch_font`. These fonts are fragile
--- because they use traditional TeX font handling.
luatexbase.call_callback ("luaotfload.patch_font", fontdata, specification, id)
else
luatexbase.call_callback ("luaotfload.patch_font_unsafe", fontdata, specification, id)
end
if not fontdata or id or tonumber(fontdata) then
return fontdata
end
id = font.define(fontdata)
register(fontdata, id)
return id
end
local function mk_info (name)
local definer = name == "patch" and patch or read
return function (specification, size, id)
logreport ("both", 0, "loaders", "defining font no. %d", id)
logreport ("both", 0, "loaders", " > active font definer: %q", name)
logreport ("both", 0, "loaders", " > spec %q", specification)
logreport ("both", 0, "loaders", " > at size %.2f pt", size / 2^16)
local result = definer (specification, size, id)
if not result then return not_found_msg (specification, size, id) end
if type (result) == "number" then
logreport ("both", 0, "loaders", " > font definition yielded id %d", result)
return result
end
logreport ("both", 0, "loaders", " > font definition successful")
logreport ("both", 0, "loaders", " > name %q", result.name or "<nil>")
logreport ("both", 0, "loaders", " > fontname %q", result.fontname or "<nil>")
logreport ("both", 0, "loaders", " > fullname %q", result.fullname or "<nil>")
logreport ("both", 0, "loaders", " > type %s", result.type or "<nil>")
local spec = result.specification
if spec then
logreport ("both", 0, "loaders", " > file %q", spec.filename or "<nil>")
logreport ("both", 0, "loaders", " > subfont %s", spec.sub or "<nil>")
end
return result
end
end
definers = {
patch = patch,
generic = read,
info_patch = mk_info "patch",
info_generic = mk_info "generic",
}
end
--[[doc--
We create callbacks for patching fonts on the fly, to be used by
other packages. In addition to the regular \identifier{patch_font}
callback there is an unsafe variant \identifier{patch_font_unsafe}
that will be invoked even if the target font lacks certain essential
tfmdata tables.
The callbacks initially contain the empty function that we are going
to override below.
--doc]]--
local function purge_define_font ()
local cdesc = luatexbase.callback_descriptions "define_font"
--- define_font is an “exclusive†callback, meaning that there can
--- only ever be one entry. Everything beyond that would indicate
--- that something is broken.
local _, d = next (cdesc)
if d then
local i, d2 = next (cdesc, 1)
if d2 then --> issue warning
logreport ("both", 0, "loaders",
"Callback table for define_font contains multiple entries: \z
{ [%d] = %q } -- seems fishy.", i, d2)
end
logreport ("log", 0, "loaders",
"Entry %q present in define_font callback; overriding.", d)
luatexbase.remove_from_callback ("define_font", d)
end
end
local install_callbacks = function ()
local create_callback = luatexbase.create_callback
local dummy_function = function () end
create_callback ("luaotfload.patch_font", "simple", dummy_function)
create_callback ("luaotfload.patch_font_unsafe", "simple", dummy_function)
purge_define_font ()
local definer = config.luaotfload.run.definer or "patch"
local selected_definer = definers[definer]
luaotfload.define_font = selected_definer
luatexbase.add_to_callback ("define_font",
selected_definer,
"luaotfload.define_font",
1)
return true
end
return function ()
if not install_formats () then
logreport ("log", 0, "loaders", "Error initializing OFM/PF{A,B} loaders.")
return false
end
if not install_callbacks () then
logreport ("log", 0, "loaders", "Error installing font loader callbacks.")
return false
end
return true
end
-- vim:tw=79:sw=2:ts=2:expandtab