diff options
Diffstat (limited to 'luaotfload-parsers.lua')
| -rw-r--r-- | luaotfload-parsers.lua | 287 |
1 files changed, 282 insertions, 5 deletions
diff --git a/luaotfload-parsers.lua b/luaotfload-parsers.lua index 5391a1d..89e3bc9 100644 --- a/luaotfload-parsers.lua +++ b/luaotfload-parsers.lua @@ -10,12 +10,289 @@ -- if not modules then modules = { } end modules ['luaotfload-parsers'] = { - version = "2.5", - comment = "companion to luaotfload.lua", - author = "Philipp Gesang", - copyright = "Luaotfload Development Team", - license = "GNU GPL v2.0" + version = "2.5", + comment = "companion to luaotfload.lua", + author = "Philipp Gesang", + copyright = "Luaotfload Development Team", + license = "GNU GPL v2.0" } +luaotfload = luaotfload or { } +luaotfload.parsers = luaotfload.parsers or { } +local parsers = luaotfload.parsers + +local lpeg = require "lpeg" +local P, R, S = lpeg.P, lpeg.R, lpeg.S +local lpegmatch = lpeg.match +local C, Cc, Cf = lpeg.C, lpeg.Cc, lpeg.Cf +local Cg, Cs, Ct = lpeg.Cg, lpeg.Cs, lpeg.Ct + +local kpse = kpse +local kpseexpand_path = kpse.expand_path +local kpsereadable_file = kpse.readable_file + +local file = file +local filejoin = file.join +local filedirname = file.dirname + +local io = io +local ioopen = io.open + +local logs = logs +local report = logs.report + +local string = string +local stringsub = string.sub +local stringfind = string.find + +local lfs = lfs +local lfsisfile = lfs.isfile +local lfsisdir = lfs.isdir + +--[[doc-- + + For fonts installed on the operating system, there are several + options to make Luaotfload index them: + + - If OSFONTDIR is set (which is the case under windows by default + but not on the other OSs), it scans it at the same time as the + texmf tree, in the function scan_texmf_fonts(). + + - Otherwise + - under Windows and Mac OSX, we take a look at some hardcoded + directories, + - under Unix, it reads /etc/fonts/fonts.conf and processes the + directories specified there. + + This means that if you have fonts in fancy directories, you need to + set them in OSFONTDIR. + + Beware: OSFONTDIR is a kpathsea variable, so fonts found in these + paths, though technically system fonts, are registered in the + category “texmf”, not “system”. This may have consequences for the + lookup order when a font file (or a font with the same name + information) is located in both the system and the texmf tree. + +--doc]]-- + +local alpha = R("az", "AZ") +local digit = R"09" +local tag_name = C(alpha^1) +local whitespace = S" \n\r\t\v" +local ws = whitespace^1 +local comment = P"<!--" * (1 - P"--")^0 * P"-->" + +---> header specifica +local xml_declaration = P"<?xml" * (1 - P"?>")^0 * P"?>" +local xml_doctype = P"<!DOCTYPE" * ws + * "fontconfig" * (1 - P">")^0 * P">" +local header = xml_declaration^-1 + * (xml_doctype + comment + ws)^0 + +---> enforce root node +local root_start = P"<" * ws^-1 * P"fontconfig" * ws^-1 * P">" +local root_stop = P"</" * ws^-1 * P"fontconfig" * ws^-1 * P">" + +local dquote, squote = P[["]], P"'" +local xml_namestartchar = S":_" + alpha --- ascii only, funk the rest +local xml_namechar = S":._" + alpha + digit +local xml_name = ws^-1 + * C(xml_namestartchar * xml_namechar^0) +local xml_attvalue = dquote * C((1 - S[[%&"]])^1) * dquote * ws^-1 + + squote * C((1 - S[[%&']])^1) * squote * ws^-1 +local xml_attr = Cg(xml_name * P"=" * xml_attvalue) +local xml_attr_list = Cf(Ct"" * xml_attr^1, rawset) + +--[[doc-- + scan_node creates a parser for a given xml tag. +--doc]]-- +--- string -> bool -> lpeg_t +local scan_node = function (tag) + --- Node attributes go into a table with the index “attributes” + --- (relevant for “prefix="xdg"” and the likes). + local p_tag = P(tag) + local with_attributes = P"<" * p_tag + * Cg(xml_attr_list, "attributes")^-1 + * ws^-1 + * P">" + local plain = P"<" * p_tag * ws^-1 * P">" + local node_start = plain + with_attributes + local node_stop = P"</" * p_tag * ws^-1 * P">" + --- there is no nesting, the earth is flat ... + local node = node_start + * Cc(tag) * C(comment + (1 - node_stop)^1) + * node_stop + return Ct(node) -- returns {string, string [, attributes = { key = val }] } +end + +--[[doc-- + At the moment, the interesting tags are “dir” for + directory declarations, and “include” for including + further configuration files. + + spec: http://freedesktop.org/software/fontconfig/fontconfig-user.html +--doc]]-- +local include_node = scan_node"include" +local dir_node = scan_node"dir" + +local element = dir_node + + include_node + + comment --> ignore + + P(1-root_stop) --> skip byte + +local root = root_start * Ct(element^0) * root_stop +local p_cheapxml = header * root + +--lpeg.print(p_cheapxml) ---> 757 rules with v0.10 + +--[[doc-- + fonts_conf_scanner() handles configuration files. + It is called on an abolute path to a config file (e.g. + /home/luser/.config/fontconfig/fonts.conf) and returns a list + of the nodes it managed to extract from the file. +--doc]]-- +--- string -> path list +local fonts_conf_scanner = function (path) + local fh = ioopen(path, "r") + if not fh then + report("both", 3, "db", "Cannot open fontconfig file %s.", path) + return + end + local raw = fh:read"*all" + fh:close() + + local confdata = lpegmatch(p_cheapxml, raw) + if not confdata then + report("both", 3, "db", "Cannot scan fontconfig file %s.", path) + return + end + return confdata +end + +local p_conf = P".conf" * P(-1) +local p_filter = (1 - p_conf)^1 * p_conf + +local conf_filter = function (path) + if lpegmatch (p_filter, path) then + return true + end + return false +end + +--[[doc-- + read_fonts_conf_indeed() is called with six arguments; the + latter three are tables that represent the state and are + always returned. + The first three are + · the path to the file + · the expanded $HOME + · the expanded $XDG_CONFIG_DIR +--doc]]-- +--- string -> string -> string -> tab -> tab -> (tab * tab * tab) +local read_fonts_conf_indeed +read_fonts_conf_indeed = function (start, home, xdg_home, + acc, done, dirs_done, + find_files) + + local paths = fonts_conf_scanner(start) + if not paths then --- nothing to do + return acc, done, dirs_done + end + + for i=1, #paths do + local pathobj = paths[i] + local kind, path = pathobj[1], pathobj[2] + local attributes = pathobj.attributes + if attributes and attributes.prefix == "xdg" then + --- this prepends the xdg root (usually ~/.config) + path = filejoin(xdg_home, path) + end + + if kind == "dir" then + if stringsub(path, 1, 1) == "~" then + path = filejoin(home, stringsub(path, 2)) + end + --- We exclude paths with texmf in them, as they should be + --- found anyway; also duplicates are ignored by checking + --- if they are elements of dirs_done. + --- + --- FIXME does this mean we cannot access paths from + --- distributions (e.g. Context minimals) installed + --- separately? + if not (stringfind(path, "texmf") or dirs_done[path]) then + acc[#acc+1] = path + dirs_done[path] = true + end + + elseif kind == "include" then + --- here the path can be four things: a directory or a file, + --- in absolute or relative path. + if stringsub(path, 1, 1) == "~" then + path = filejoin(home, stringsub(path, 2)) + elseif --- if the path is relative, we make it absolute + not ( lfsisfile(path) or lfsisdir(path) ) + then + path = filejoin(filedirname(start), path) + end + if lfsisfile(path) + and kpsereadable_file(path) + and not done[path] + then + --- we exclude path with texmf in them, as they should + --- be found otherwise + acc = read_fonts_conf_indeed( + path, home, xdg_home, + acc, done, dirs_done) + elseif lfsisdir(path) then --- arrow code ahead + local config_files = find_files (path, conf_filter) + for _, filename in next, config_files do + if not done[filename] then + acc = read_fonts_conf_indeed( + filename, home, xdg_home, + acc, done, dirs_done) + end + end + end --- match “kind” + end --- iterate paths + end + + --inspect(acc) + --inspect(done) + return acc, done, dirs_done + end --- read_fonts_conf_indeed() + +--[[doc-- + read_fonts_conf() sets up an accumulator and two sets + for tracking what’s been done. + + Also, the environment variables HOME and XDG_CONFIG_HOME -- + which are constants anyways -- are expanded so don’t have to + repeat that over and over again as with the old parser. + Now they’re just passed on to every call of + read_fonts_conf_indeed(). + + read_fonts_conf() is also the only reference visible outside + the closure. +--doc]]-- + +--- list -> (string -> function option -> string list) -> list + +local read_fonts_conf = function (path_list, find_files) + local home = kpseexpand_path"~" --- could be os.getenv"HOME" + local xdg_home = kpseexpand_path"$XDG_CONFIG_HOME" + if xdg_home == "" then xdg_home = filejoin(home, ".config") end + local acc = { } ---> list: paths collected + local done = { } ---> set: files inspected + local dirs_done = { } ---> set: dirs in list + for i=1, #path_list do --- we keep the state between files + acc, done, dirs_done = read_fonts_conf_indeed( + path_list[i], home, xdg_home, + acc, done, dirs_done, + find_files) + end + return acc +end + +luaotfload.parsers.read_fonts_conf = read_fonts_conf |