diff options
Diffstat (limited to 'source/unzip/unreduce.c')
| -rw-r--r-- | source/unzip/unreduce.c | 217 |
1 files changed, 0 insertions, 217 deletions
diff --git a/source/unzip/unreduce.c b/source/unzip/unreduce.c deleted file mode 100644 index e978746..0000000 --- a/source/unzip/unreduce.c +++ /dev/null @@ -1,217 +0,0 @@ -/*--------------------------------------------------------------------------- - - unreduce.c - - The Reducing algorithm is actually a combination of two distinct algorithms. - The first algorithm compresses repeated byte sequences, and the second al- - gorithm takes the compressed stream from the first algorithm and applies a - probabilistic compression method. - - ---------------------------------------------------------------------------*/ - - -#include "unz.h" -#include "unzipP.h" - -/**************************************/ -/* UnReduce Defines, Typedefs, etc. */ -/**************************************/ - -#define DLE 144 - -typedef byte f_array[64]; /* for followers[256][64] */ - -static void LoadFollowers (); -void flush OF((unsigned)); /* routine from inflate.c */ - -extern file_in_zip_read_info_s *pfile_in_zip_read_info; -extern unz_s *pUnzip; - -/*******************************/ -/* UnReduce Global Variables */ -/*******************************/ - -#if (defined(MACOS) || defined(MTS)) - f_array *followers; /* shared work space */ -#else - f_array *followers = (f_array *) (slide + 0x4000); -#endif - -byte Slen[256]; -int factor; - -int L_table[] = -{0, 0x7f, 0x3f, 0x1f, 0x0f}; - -int D_shift[] = -{0, 0x07, 0x06, 0x05, 0x04}; -int D_mask[] = -{0, 0x01, 0x03, 0x07, 0x0f}; - -int B_table[] = -{8, 1, 1, 2, 2, 3, 3, 3, 3, 4, 4, 4, 4, 4, 4, 4, 4, 5, - 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 6, 6, 6, - 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, - 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 7, 7, 7, 7, 7, 7, 7, - 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, - 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, - 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, - 7, 7, 7, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, - 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, - 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, - 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, - 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, - 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, - 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, - 8, 8, 8, 8}; - - - - - -/*************************/ -/* Function unReduce() */ -/*************************/ - -void unReduce() /* expand probabilistically reduced data */ -{ - register int lchar = 0; - int nchar; - int ExState = 0; - int V = 0; - int Len = 0; - longint s = pUnzip->pfile_in_zip_read->rest_read_compressed; - unsigned w = 0; /* position in output window slide[] */ - unsigned u = 1; /* true if slide[] unflushed */ - - -#if (defined(MACOS) || defined(MTS)) - followers = (f_array *) (slide + 0x4000); -#endif - - factor = pUnzip->cur_file_info.compression_method; - LoadFollowers(); - - while (s > 0 /* && (!zipeof) */) { - if (Slen[lchar] == 0) - READBIT(8, nchar) /* ; */ - else { - READBIT(1, nchar); - if (nchar != 0) - READBIT(8, nchar) /* ; */ - else { - int follower; - int bitsneeded = B_table[Slen[lchar]]; - READBIT(bitsneeded, follower); - nchar = followers[lchar][follower]; - } - } - /* expand the resulting byte */ - switch (ExState) { - - case 0: - if (nchar != DLE) { - s--; - slide[w++] = (byte) nchar; - if (w == 0x4000) { - flush(w); - w = u = 0; - } - } - else - ExState = 1; - break; - - case 1: - if (nchar != 0) { - V = nchar; - Len = V & L_table[factor]; - if (Len == L_table[factor]) - ExState = 2; - else - ExState = 3; - } else { - s--; - slide[w++] = DLE; - if (w == 0x4000) - { - flush(w); - w = u = 0; - } - ExState = 0; - } - break; - - case 2:{ - Len += nchar; - ExState = 3; - } - break; - - case 3:{ - register unsigned e; - register unsigned n = Len + 3; - register unsigned d = w - ((((V >> D_shift[factor]) & - D_mask[factor]) << 8) + nchar + 1); - - s -= n; - do { - n -= (e = (e = 0x4000 - ((d &= 0x3fff) > w ? d : w)) > n ? - n : e); - if (u && w <= d) - { - memset(slide + w, 0, e); - w += e; - d += e; - } - else - if (w - d < e) /* (assume unsigned comparison) */ - do { /* slow to avoid memcpy() overlap */ - slide[w++] = slide[d++]; - } while (--e); - else - { - memcpy(slide + w, slide + d, e); - w += e; - d += e; - } - if (w == 0x4000) - { - flush(w); - w = u = 0; - } - } while (n); - - ExState = 0; - } - break; - } - - /* store character for next iteration */ - lchar = nchar; - } - - /* flush out slide */ - flush(w); -} - - - - - -/******************************/ -/* Function LoadFollowers() */ -/******************************/ - -static void LoadFollowers() -{ - register int x; - register int i; - - for (x = 255; x >= 0; x--) { - READBIT(6, Slen[x]); - for (i = 0; (byte) i < Slen[x]; i++) { - READBIT(8, followers[x][i]); - } - } -} |