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author | Philipp Gesang <phg42.2a@gmail.com> | 2013-04-26 14:19:00 +0200 |
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committer | Philipp Gesang <phg42.2a@gmail.com> | 2013-04-26 14:19:00 +0200 |
commit | b2659be825b80de3201a3df17cc1dc2d4bcf296d (patch) | |
tree | 02c7eaedbb98e686e1d83455cc7ecf78cb62db6a | |
parent | 29620364877381833baaf5c767177413c125d3cd (diff) | |
download | luaotfload-b2659be825b80de3201a3df17cc1dc2d4bcf296d.tar.gz |
add draft lookup cache
-rw-r--r-- | luaotfload-database.lua | 117 |
1 files changed, 111 insertions, 6 deletions
diff --git a/luaotfload-database.lua b/luaotfload-database.lua index 1b13f69..55966bf 100644 --- a/luaotfload-database.lua +++ b/luaotfload-database.lua @@ -61,8 +61,11 @@ local tableappend = table.append local tabletohash = table.tohash --- the font loader namespace is “fonts”, same as in Context -fonts = fonts or { } -fonts.names = fonts.names or { } +--- we need to put some fallbacks into place for when running +--- as a script +fonts = fonts or { } +fonts.names = fonts.names or { } +fonts.definers = fonts.definers or { } local names = fonts.names @@ -73,6 +76,7 @@ names.path = { dir = "", path = "", } +local lookup_cache = nil --> names.data.cache; populated by load_names -- We use the cache.* of ConTeXt (see luat-basics-gen), we can -- use it safely (all checks and directory creations are already done). It @@ -108,6 +112,7 @@ This is a sketch of the luaotfload db: // preliminary additions of v2.2: basenames : (string, int) hash; // where int is the index in mappings barenames : (string, int) hash; // where int is the index in mappings + caches : lookup_cache; // see below } and fontentry = { familyname : string; @@ -165,7 +170,7 @@ mtx-fonts has in names.tma: --doc]]-- -local fontnames_init = function ( ) +local fontnames_init = function ( ) --- returns clean dbobj return { mappings = { }, status = { }, @@ -178,6 +183,10 @@ local fontnames_init = function ( ) basenames = { }, -- fullnames = { }, version = names.version, + caches = { --- new + file = { }, name = { }, + path = { }, anon = { }, + } } end @@ -242,6 +251,7 @@ load_names = function ( ) "Font names database loaded", "%s", foundname) report("info", 3, "db", "Loading took %0.f ms", 1000*(os.gettimeofday()-starttime)) + lookup_cache = data.caches else report("info", 1, "db", [[Font names database not found, generating new one. @@ -249,6 +259,7 @@ load_names = function ( ) data = update_names(fontnames_init()) save_names(data) end + fonts_loaded = true return data end @@ -342,6 +353,101 @@ local crude_file_lookup = function (data, filename) end --[[doc-- +Lookups can be quite costly, more so the less specific they are. +Even if we find a matching font eventually, the next time the +user compiles Eir document E will have to stand through the delay +again. +Thus, some caching of results -- even between runs -- is in order. +We’ll just store successful lookups in the database in a record of +the respective lookup type. + +type lookup_cache = { + file : lookups; + name : lookups; + path : lookups; + anon : lookups; +} +and lookups = (string, (string * num)) dict + +TODO: + × 1) add cache to dbobj + × 2) wrap lookups in cached versions + 3) make caching optional (via the config table) for debugging + 4) make names_update() cache aware (nil if “force”) + × 5) add logging + 6) add cache control to fontdbutil + 7) incr db version + 8) ??? + n) PROFIT!!! + +--doc]]-- + +--- the resolver is called after the font request is parsed +--- this is where we insert the cache +local normal_resolve = fonts.definers.resolve +local dummyresolver = function (specification) + --- this ensures that the db is always loaded + --- before a lookup occurs + if not fonts_loaded then names.data = load_names() end + inspect(normal_resolve(specification)) + return normal_resolve(specification) +end + +--[[doc-- +The name lookup requires both the “name” and the “style” +key, so we’ll concatenate them. +--doc]]-- +--- string -> spec -> string +local to_hash_field = function (lookup, specification) + if lookup == "name" and specification.style then + return specification.name.."*"..specification.style + end + return specification.name +end + +--[[doc-- +From my reading of font-def.lua, what a resolver does is +basically rewrite the “name” field of the specification record +with the resolution. +Also, the fields “resolved”, “sub”, “force” etc. influence the outcome. + +We’ll just cache a deep copy of the entire spec as it leaves the +resolver, lest we want to worry if we caught all the details. +--doc]]-- + +local cached_resolver = function (specification) + if not lookup_cache then names.data = load_names() end + local lookup = specification.lookup + local field = to_hash_field(lookup, specification) + local cached = lookup_cache[lookup] + report("info", 4, "cache", + "looking up field “%s” in category “%s” ...", + field, lookup) + local hit = cached[field] + if hit then + report("info", 4, "cache", "found!") + return hit + end + report("info", 4, "cache", "not cached; resolving") + + --- here we add to the cache + local resolved_spec = normal_resolve(specification) + cached[field] = tablecopy(resolved_spec) --- slow for the first time + --- obviously, the updated cache needs to be stored. + --- for the moment, we write the entire db to disk + --- whenever the cache is updated. + --- TODO this should trigger a save only once the + --- document is compiled (finish_pdffile callback?) + report("info", 5, "cache", "saving updated cache") + save_names(names.data) + return resolved_spec +end + +--fonts.definers.resolve = dummyresolver +--fonts.definers.resolve = normalresolver +fonts.definers.resolve = cached_resolver + +--[[doc-- Luatex-fonts, the font-loader package luaotfload imports, comes with basic file location facilities (see luatex-fonts-syn.lua). @@ -382,10 +488,11 @@ font database created by the mkluatexfontdb script. resolve = function (_,_,specification) -- the 1st two parameters are used by ConTeXt if not fonts_loaded then names.data = load_names() - fonts_loaded = true end local data = names.data + --inspect(specification) + --os.exit() if specification.lookup == "file" then local found = crude_file_lookup(data, specification.name) --local found = crude_file_lookup_verbose(data, specification.name) @@ -607,7 +714,6 @@ find_closest = function (name, limit) if not fonts_loaded then names.data = load_names() - fonts_loaded = true end local data = names.data @@ -1234,7 +1340,6 @@ scan_external_dir = function (dir) old_names = names.data else old_names = load_names() - fonts_loaded = true end new_names = tablecopy(old_names) local n_scanned, n_new = scan_dir(dir, old_names, new_names) |