diff options
Diffstat (limited to 'Master/texmf-dist/tex/context/base/mkiv/lpdf-aux.lua')
-rw-r--r-- | Master/texmf-dist/tex/context/base/mkiv/lpdf-aux.lua | 152 |
1 files changed, 152 insertions, 0 deletions
diff --git a/Master/texmf-dist/tex/context/base/mkiv/lpdf-aux.lua b/Master/texmf-dist/tex/context/base/mkiv/lpdf-aux.lua new file mode 100644 index 00000000000..0d7cecbb853 --- /dev/null +++ b/Master/texmf-dist/tex/context/base/mkiv/lpdf-aux.lua @@ -0,0 +1,152 @@ +if not modules then modules = { } end modules ['lpdf-aux'] = { + version = 1.001, + comment = "companion to lpdf-ini.mkiv", + author = "Hans Hagen, PRAGMA-ADE, Hasselt NL", + copyright = "PRAGMA ADE / ConTeXt Development Team", + license = "see context related readme files" +} + +local tonumber = tonumber +local format, concat = string.format, table.concat +local utfchar, utfbyte, char = utf.char, utf.byte, string.char +local lpegmatch, lpegpatterns = lpeg.match, lpeg.patterns +local P, C, R, S, Cc, Cs, V = lpeg.P, lpeg.C, lpeg.R, lpeg.S, lpeg.Cc, lpeg.Cs, lpeg.V +local rshift = bit32.rshift + +lpdf = lpdf or { } + +-- tosixteen -- + +local cache = table.setmetatableindex(function(t,k) -- can be made weak + local v = utfbyte(k) + if v < 0x10000 then + v = format("%04x",v) + else + v = format("%04x%04x",rshift(v,10),v%1024+0xDC00) + end + t[k] = v + return v +end) + +local unified = Cs(Cc("<feff") * (lpegpatterns.utf8character/cache)^1 * Cc(">")) + +function lpdf.tosixteen(str) -- an lpeg might be faster (no table) + if not str or str == "" then + return "<feff>" -- not () as we want an indication that it's unicode + else + return lpegmatch(unified,str) + end +end + +-- fromsixteen -- + +-- local zero = S(" \n\r\t") + P("\\ ") +-- local one = C(4) +-- local two = P("d") * R("89","af") * C(2) * C(4) +-- +-- local pattern = P { "start", +-- start = V("wrapped") + V("unwrapped") + V("original"), +-- original = Cs(P(1)^0), +-- wrapped = P("<") * V("unwrapped") * P(">") * P(-1), +-- unwrapped = P("feff") +-- * Cs( ( +-- zero / "" +-- + two / function(a,b) +-- a = (tonumber(a,16) - 0xD800) * 1024 +-- b = (tonumber(b,16) - 0xDC00) +-- return utfchar(a+b) +-- end +-- + one / function(a) +-- return utfchar(tonumber(a,16)) +-- end +-- )^1 ) * P(-1) +-- } +-- +-- function lpdf.fromsixteen(s) +-- return lpegmatch(pattern,s) or s +-- end + +local more = 0 + +local pattern = C(4) / function(s) -- needs checking ! + local now = tonumber(s,16) + if more > 0 then + now = (more-0xD800)*0x400 + (now-0xDC00) + 0x10000 -- the 0x10000 smells wrong + more = 0 + return utfchar(now) + elseif now >= 0xD800 and now <= 0xDBFF then + more = now + return "" -- else the c's end up in the stream + else + return utfchar(now) + end +end + +local pattern = P(true) / function() more = 0 end * Cs(pattern^0) + +function lpdf.fromsixteen(str) + if not str or str == "" then + return "" + else + return lpegmatch(pattern,str) + end +end + +-- frombytes -- + +local b_pattern = Cs((P("\\")/"" * ( + S("()") + + S("nrtbf")/ { n = "\n", r = "\r", t = "\t", b = "\b", f = "\f" } + + lpegpatterns.octdigit^-3 / function(s) return char(tonumber(s,8)) end) ++ P(1))^0) + +local u_pattern = lpegpatterns.utfbom_16_be * lpegpatterns.utf16_to_utf8_be -- official + + lpegpatterns.utfbom_16_le * lpegpatterns.utf16_to_utf8_le -- we've seen these + +local h_pattern = lpegpatterns.hextobytes + +local zero = S(" \n\r\t") + P("\\ ") +local one = C(4) +local two = P("d") * R("89","af") * C(2) * C(4) + +local x_pattern = P { "start", + start = V("wrapped") + V("unwrapped") + V("original"), + original = Cs(P(1)^0), + wrapped = P("<") * V("unwrapped") * P(">") * P(-1), + unwrapped = P("feff") + * Cs( ( + zero / "" + + two / function(a,b) + a = (tonumber(a,16) - 0xD800) * 1024 + b = (tonumber(b,16) - 0xDC00) + return utfchar(a+b) + end + + one / function(a) + return utfchar(tonumber(a,16)) + end + )^1 ) * P(-1) +} + +function lpdf.frombytes(s,hex) + if not s or s == "" then + return "" + end + if hex then + local x = lpegmatch(x_pattern,s) + if x then + return x + end + local h = lpegmatch(h_pattern,s) + if h then + return h + end + else + local u = lpegmatch(u_pattern,s) + if u then + return u + end + end + return lpegmatch(b_pattern,s) +end + +-- done -- |