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Diffstat (limited to 'zlib/trees.c')
-rw-r--r--zlib/trees.c50
1 files changed, 14 insertions, 36 deletions
diff --git a/zlib/trees.c b/zlib/trees.c
index 1fd7759e..9c667702 100644
--- a/zlib/trees.c
+++ b/zlib/trees.c
@@ -418,7 +418,7 @@ local void init_block(s)
s->dyn_ltree[END_BLOCK].Freq = 1;
s->opt_len = s->static_len = 0L;
- s->last_lit = s->matches = 0;
+ s->sym_next = s->matches = 0;
}
#define SMALLEST 1
@@ -943,7 +943,7 @@ void ZLIB_INTERNAL _tr_flush_block(s, buf, stored_len, last)
Tracev((stderr, "\nopt %lu(%lu) stat %lu(%lu) stored %lu lit %u ",
opt_lenb, s->opt_len, static_lenb, s->static_len, stored_len,
- s->last_lit));
+ s->sym_next / 3));
if (static_lenb <= opt_lenb) opt_lenb = static_lenb;
@@ -1012,8 +1012,9 @@ int ZLIB_INTERNAL _tr_tally (s, dist, lc)
unsigned dist; /* distance of matched string */
unsigned lc; /* match length-MIN_MATCH or unmatched char (if dist==0) */
{
- s->d_buf[s->last_lit] = (ush)dist;
- s->l_buf[s->last_lit++] = (uch)lc;
+ s->sym_buf[s->sym_next++] = dist;
+ s->sym_buf[s->sym_next++] = dist >> 8;
+ s->sym_buf[s->sym_next++] = lc;
if (dist == 0) {
/* lc is the unmatched char */
s->dyn_ltree[lc].Freq++;
@@ -1028,30 +1029,7 @@ int ZLIB_INTERNAL _tr_tally (s, dist, lc)
s->dyn_ltree[_length_code[lc]+LITERALS+1].Freq++;
s->dyn_dtree[d_code(dist)].Freq++;
}
-
-#ifdef TRUNCATE_BLOCK
- /* Try to guess if it is profitable to stop the current block here */
- if ((s->last_lit & 0x1fff) == 0 && s->level > 2) {
- /* Compute an upper bound for the compressed length */
- ulg out_length = (ulg)s->last_lit*8L;
- ulg in_length = (ulg)((long)s->strstart - s->block_start);
- int dcode;
- for (dcode = 0; dcode < D_CODES; dcode++) {
- out_length += (ulg)s->dyn_dtree[dcode].Freq *
- (5L+extra_dbits[dcode]);
- }
- out_length >>= 3;
- Tracev((stderr,"\nlast_lit %u, in %ld, out ~%ld(%ld%%) ",
- s->last_lit, in_length, out_length,
- 100L - out_length*100L/in_length));
- if (s->matches < s->last_lit/2 && out_length < in_length/2) return 1;
- }
-#endif
- return (s->last_lit == s->lit_bufsize-1);
- /* We avoid equality with lit_bufsize because of wraparound at 64K
- * on 16 bit machines and because stored blocks are restricted to
- * 64K-1 bytes.
- */
+ return (s->sym_next == s->sym_end);
}
/* ===========================================================================
@@ -1064,13 +1042,14 @@ local void compress_block(s, ltree, dtree)
{
unsigned dist; /* distance of matched string */
int lc; /* match length or unmatched char (if dist == 0) */
- unsigned lx = 0; /* running index in l_buf */
+ unsigned sx = 0; /* running index in sym_buf */
unsigned code; /* the code to send */
int extra; /* number of extra bits to send */
- if (s->last_lit != 0) do {
- dist = s->d_buf[lx];
- lc = s->l_buf[lx++];
+ if (s->sym_next != 0) do {
+ dist = s->sym_buf[sx++] & 0xff;
+ dist += (unsigned)(s->sym_buf[sx++] & 0xff) << 8;
+ lc = s->sym_buf[sx++];
if (dist == 0) {
send_code(s, lc, ltree); /* send a literal byte */
Tracecv(isgraph(lc), (stderr," '%c' ", lc));
@@ -1095,11 +1074,10 @@ local void compress_block(s, ltree, dtree)
}
} /* literal or match pair ? */
- /* Check that the overlay between pending_buf and d_buf+l_buf is ok: */
- Assert((uInt)(s->pending) < s->lit_bufsize + 2*lx,
- "pendingBuf overflow");
+ /* Check that the overlay between pending_buf and sym_buf is ok: */
+ Assert(s->pending < s->lit_bufsize + sx, "pendingBuf overflow");
- } while (lx < s->last_lit);
+ } while (sx < s->sym_next);
send_code(s, END_BLOCK, ltree);
}