diff options
Diffstat (limited to 'appl/lib/deflate.b')
| -rw-r--r-- | appl/lib/deflate.b | 122 |
1 files changed, 104 insertions, 18 deletions
diff --git a/appl/lib/deflate.b b/appl/lib/deflate.b index ccfeafbe..500b3797 100644 --- a/appl/lib/deflate.b +++ b/appl/lib/deflate.b @@ -42,6 +42,7 @@ GZCRCPOLY: con int 16redb88320; GZOSINFERNO: con GZOSUNIX; +Hnone, Hgzip, Hzlib: con iota; # LZstate.headers LZstate: adt { hist: array of byte; # [HistSize]; @@ -56,11 +57,13 @@ LZstate: adt prevoff: int; maxchars: int; # compressor tuning maxdefer: int; + level: int; - crctab: array of int; + crctab: array of int; # for gzip trailer crc: int; tot: int; - headers: int; + sum: big; # for zlib trailer + headers: int; # which header to print, if any outbuf: array of byte; # current output buffer; out: int; # current position in the output buffer @@ -287,22 +290,27 @@ start(param: string): chan of ref Rq { # param contains flags: # [0-9] - compression level + # h gzip header/trailer + # z zlib header/trailer # v verbose # d debug lz := ref LZstate; - level := 6; + lz.level = 6; lz.verbose = lz.debug = 0; - lz.headers = 0; + lz.headers = Hnone; lz.crc = lz.tot = 0; + lz.sum = big 1; # XXX could also put filename and modification time in param for (i := 0; i < len param; i++) { case param[i] { '0' to '9' => - level = param[i] - '0'; + lz.level = param[i] - '0'; 'v' => lz.verbose = 1; 'h' => - lz.headers = 1; + lz.headers = Hgzip; + 'z' => + lz.headers = Hzlib; 'd' => lz.debug = 1; } @@ -345,17 +353,17 @@ start(param: string): chan of ref Rq lz.dot = lz.me; lz.bits = 0; lz.nbits = 0; - if(level < 5) { + if(lz.level < 5) { lz.maxchars = 1; lz.maxdefer = 0; - } else if(level == 9) { + } else if(lz.level == 9) { lz.maxchars = 4000; lz.maxdefer = MaxMatch; } else { lz.maxchars = 200; lz.maxdefer = MaxMatch / 4; } - if (lz.headers) + if (lz.headers == Hgzip) lz.crctab = mkcrctab(GZCRCPOLY); lz.c = chan of ref Rq; lz.rc = chan of int; @@ -383,8 +391,7 @@ deflate(lz: ref LZstate) { lz.c <-= ref Rq.Start(sys->pctl(0, nil)); - if (lz.headers) - header(lz); + header(lz); buf := array[DeflateBlock] of byte; out := array[DeflateBlock + DeflateOut] of byte; eof := 0; @@ -393,8 +400,7 @@ deflate(lz: ref LZstate) nbuf := 0; if (!eof) { (eof, nbuf) = fillbuf(lz, buf); - if (lz.headers) # added by Roman Joel Pacheco - inblock(lz, buf[0:nbuf]); + inblock(lz, buf[0:nbuf]); } if(eof && nbuf == 0 && nslop == 0) { if(lz.nbits) { @@ -405,8 +411,7 @@ deflate(lz: ref LZstate) exit; continue; } - if (lz.headers) - footer(lz); + footer(lz); lz.c <-= ref Rq.Finished(nil); exit; } @@ -538,7 +543,7 @@ deflate(lz: ref LZstate) } } -header(lz: ref LZstate) +headergzip(lz: ref LZstate) { buf := array[20] of byte; i := 0; @@ -569,7 +574,44 @@ header(lz: ref LZstate) exit; } -footer(lz: ref LZstate) +headerzlib(lz: ref LZstate) +{ + CIshift: con 12; + CMdeflate: con 8; + CMshift: con 8; + LVshift: con 6; + LVfastest, LVfast, LVnormal, LVbest: con iota; + + level := LVnormal; + if(lz.level < 6) + level = LVfastest; + else if(lz.level >= 9) + level = LVbest; + + h := 0; + h |= 7<<CIshift; # value is: (log2 of window size)-8 + h |= CMdeflate<<CMshift; + h |= level<<LVshift; + h += 31-(h%31); + + buf := array[2] of byte; + buf[0] = byte (h>>8); + buf[1] = byte (h>>0); + + lz.c <-= ref Rq.Result(buf, lz.rc); + if (<-lz.rc == -1) + exit; +} + +header(lz: ref LZstate) +{ + case lz.headers { + Hgzip => headergzip(lz); + Hzlib => headerzlib(lz); + } +} + +footergzip(lz: ref LZstate) { buf := array[8] of byte; i := 0; @@ -587,6 +629,28 @@ footer(lz: ref LZstate) exit; } +footerzlib(lz: ref LZstate) +{ + buf := array[4] of byte; + i := 0; + buf[i++] = byte (lz.sum>>24); + buf[i++] = byte (lz.sum>>16); + buf[i++] = byte (lz.sum>>8); + buf[i++] = byte (lz.sum>>0); + + lz.c <-= ref Rq.Result(buf, lz.rc); + if(<-lz.rc == -1) + exit; +} + +footer(lz: ref LZstate) +{ + case lz.headers { + Hgzip => footergzip(lz); + Hzlib => footerzlib(lz); + } +} + lzput(lz: ref LZstate, bits, nbits: int): int { bits = (bits << lz.nbits) | lz.bits; @@ -1349,7 +1413,7 @@ mkcrctab(poly: int): array of int return crctab; } -inblock(lz: ref LZstate, buf: array of byte) +inblockcrc(lz: ref LZstate, buf: array of byte) { crc := lz.crc; n := len buf; @@ -1360,6 +1424,28 @@ inblock(lz: ref LZstate, buf: array of byte) lz.tot += n; } +inblockadler(lz: ref LZstate, buf: array of byte) +{ + ZLADLERBASE: con big 65521; + + s1 := lz.sum & big 16rffff; + s2 := (lz.sum>>16) & big 16rffff; + + for(i := 0; i < len buf; i++) { + s1 = (s1 + big buf[i]) % ZLADLERBASE; + s2 = (s2 + s1) % ZLADLERBASE; + } + lz.sum = (s2<<16) + s1; +} + +inblock(lz: ref LZstate, buf: array of byte) +{ + case lz.headers { + Hgzip => inblockcrc(lz, buf); + Hzlib => inblockadler(lz, buf); + } +} + fatal(lz: ref LZstate, s: string) { lz.c <-= ref Rq.Error(s); |