diff options
Diffstat (limited to 'tex/context/base/mkiv/util-sac.lua')
| -rw-r--r-- | tex/context/base/mkiv/util-sac.lua | 230 |
1 files changed, 208 insertions, 22 deletions
diff --git a/tex/context/base/mkiv/util-sac.lua b/tex/context/base/mkiv/util-sac.lua index 8a12e7cf0..b509d9a9b 100644 --- a/tex/context/base/mkiv/util-sac.lua +++ b/tex/context/base/mkiv/util-sac.lua @@ -10,7 +10,7 @@ if not modules then modules = { } end modules ['util-sac'] = { -- with bytes) local byte, sub = string.byte, string.sub -local extract = bit32.extract +local extract = bit32 and bit32.extract utilities = utilities or { } local streams = { } @@ -82,6 +82,13 @@ function streams.readbytes(f,n) return byte(f[1],i,j-1) end +function streams.readbytetable(f,n) + local i = f[2] + local j = i + n + f[2] = j + return { byte(f[1],i,j-1) } +end + function streams.skipbytes(f,n) f[2] = f[2] + n end @@ -104,7 +111,7 @@ function streams.readinteger1(f) -- one byte f[2] = i + 1 local n = byte(f[1],i) if n >= 0x80 then - return n - 0xFF - 1 + return n - 0x100 else return n end @@ -122,16 +129,35 @@ function streams.readcardinal2(f) return 0x100 * a + b end +function streams.readcardinal2LE(f) + local i = f[2] + local j = i + 1 + f[2] = j + 1 + local b, a = byte(f[1],i,j) + return 0x100 * a + b +end + function streams.readinteger2(f) local i = f[2] local j = i + 1 f[2] = j + 1 local a, b = byte(f[1],i,j) - local n = 0x100 * a + b - if n >= 0x8000 then - return n - 0xFFFF - 1 + if a >= 0x80 then + return 0x100 * a + b - 0x10000 else - return n + return 0x100 * a + b + end +end + +function streams.readinteger2le(f) + local i = f[2] + local j = i + 1 + f[2] = j + 1 + local b, a = byte(f[1],i,j) + if a >= 0x80 then + return 0x100 * a + b - 0x10000 + else + return 0x100 * a + b end end @@ -143,6 +169,38 @@ function streams.readcardinal3(f) return 0x10000 * a + 0x100 * b + c end +function streams.readcardinal3le(f) + local i = f[2] + local j = i + 2 + f[2] = j + 1 + local c, b, a = byte(f[1],i,j) + return 0x10000 * a + 0x100 * b + c +end + +function streams.readinteger3(f) + local i = f[2] + local j = i + 3 + f[2] = j + 1 + local a, b, c = byte(f[1],i,j) + if a >= 0x80 then + return 0x10000 * a + 0x100 * b + c - 0x1000000 + else + return 0x10000 * a + 0x100 * b + c + end +end + +function streams.readinteger3le(f) + local i = f[2] + local j = i + 3 + f[2] = j + 1 + local c, b, a = byte(f[1],i,j) + if a >= 0x80 then + return 0x10000 * a + 0x100 * b + c - 0x1000000 + else + return 0x10000 * a + 0x100 * b + c + end +end + function streams.readcardinal4(f) local i = f[2] local j = i + 3 @@ -156,11 +214,22 @@ function streams.readinteger4(f) local j = i + 3 f[2] = j + 1 local a, b, c, d = byte(f[1],i,j) - local n = 0x1000000 * a + 0x10000 * b + 0x100 * c + d - if n >= 0x8000000 then - return n - 0xFFFFFFFF - 1 + if a >= 0x80 then + return 0x1000000 * a + 0x10000 * b + 0x100 * c + d - 0x100000000 else - return n + return 0x1000000 * a + 0x10000 * b + 0x100 * c + d + end +end + +function streams.readinteger4le(f) + local i = f[2] + local j = i + 3 + f[2] = j + 1 + local d, c, b, a = byte(f[1],i,j) + if a >= 0x80 then + return 0x1000000 * a + 0x10000 * b + 0x100 * c + d - 0x100000000 + else + return 0x1000000 * a + 0x10000 * b + 0x100 * c + d end end @@ -169,30 +238,46 @@ function streams.readfixed4(f) local j = i + 3 f[2] = j + 1 local a, b, c, d = byte(f[1],i,j) - local n = 0x100 * a + b - if n >= 0x8000 then - return n - 0xFFFF - 1 + (0x100 * c + d)/0xFFFF + if a >= 0x80 then + return (0x100 * a + b - 0x10000) + (0x100 * c + d)/0x10000 else - return n + (0x100 * c + d)/0xFFFF + return (0x100 * a + b ) + (0x100 * c + d)/0x10000 end end -function streams.read2dot14(f) +function streams.readfixed2(f) local i = f[2] local j = i + 1 f[2] = j + 1 local a, b = byte(f[1],i,j) - local n = 0x100 * a + b - local m = extract(n,0,30) - if n > 0x7FFF then - n = extract(n,30,2) - return m/0x4000 - 4 + if a >= 0x80 then + return (a - 0x100) + b/0x100 else - n = extract(n,30,2) - return n + m/0x4000 + return (a ) + b/0x100 end end +if extract then + + local extract = bit32.extract + local band = bit32.band + + function streams.read2dot14(f) + local i = f[2] + local j = i + 1 + f[2] = j + 1 + local a, b = byte(f[1],i,j) + if a >= 0x80 then + local n = -(0x100 * a + b) + return - (extract(n,14,2) + (band(n,0x3FFF) / 16384.0)) + else + local n = 0x100 * a + b + return (extract(n,14,2) + (band(n,0x3FFF) / 16384.0)) + end + end + +end + function streams.skipshort(f,n) f[2] = f[2] + 2*(n or 1) end @@ -200,3 +285,104 @@ end function streams.skiplong(f,n) f[2] = f[2] + 4*(n or 1) end + +if sio and sio.readcardinal2 then + + local readcardinal1 = sio.readcardinal1 + local readcardinal2 = sio.readcardinal2 + local readcardinal3 = sio.readcardinal3 + local readcardinal4 = sio.readcardinal4 + local readinteger1 = sio.readinteger1 + local readinteger2 = sio.readinteger2 + local readinteger3 = sio.readinteger3 + local readinteger4 = sio.readinteger4 + local readfixed2 = sio.readfixed2 + local readfixed4 = sio.readfixed4 + local read2dot14 = sio.read2dot14 + local readbytes = sio.readbytes + local readbytetable = sio.readbytetable + + function streams.readcardinal1(f) + local i = f[2] + f[2] = i + 1 + return readcardinal1(f[1],i) + end + function streams.readcardinal2(f) + local i = f[2] + f[2] = i + 2 + return readcardinal2(f[1],i) + end + function streams.readcardinal3(f) + local i = f[2] + f[2] = i + 3 + return readcardinal3(f[1],i) + end + function streams.readcardinal4(f) + local i = f[2] + f[2] = i + 4 + return readcardinal4(f[1],i) + end + function streams.readinteger1(f) + local i = f[2] + f[2] = i + 1 + return readinteger1(f[1],i) + end + function streams.readinteger2(f) + local i = f[2] + f[2] = i + 2 + return readinteger2(f[1],i) + end + function streams.readinteger3(f) + local i = f[2] + f[2] = i + 3 + return readinteger3(f[1],i) + end + function streams.readinteger4(f) + local i = f[2] + f[2] = i + 4 + return readinteger4(f[1],i) + end + -- function streams.readfixed2(f) -- needs recent luatex + -- local i = f[2] + -- f[2] = i + 2 + -- return readfixed2(f[1],i) + -- end + -- function streams.readfixed4(f) -- needs recent luatex + -- local i = f[2] + -- f[2] = i + 4 + -- return readfixed4(f[1],i) + -- end + function streams.read2dot4(f) + local i = f[2] + f[2] = i + 2 + return read2dot4(f[1],i) + end + function streams.readbytes(f,n) + local i = f[2] + local s = f[3] + local p = i + n + if p > s then + f[2] = s + 1 + else + f[2] = p + end + return readbytes(f[1],i,n) + end + function streams.readbytetable(f,n) + local i = f[2] + local s = f[3] + local p = i + n + if p > s then + f[2] = s + 1 + else + f[2] = p + end + return readbytetable(f[1],i,n) + end + + streams.readbyte = streams.readcardinal1 + streams.readsignedbyte = streams.readinteger1 + streams.readcardinal = streams.readcardinal1 + streams.readinteger = streams.readinteger1 + +end |