From 1a03c21adfd1da80893aac75bb57094c702db031 Mon Sep 17 00:00:00 2001 From: Denis Vlasenko Date: Sun, 7 Jan 2007 19:39:34 +0000 Subject: [PATCH] gzip cleanup part #6 --- archival/gzip.c | 78 ++++++++++++++++++++++++++++--------------------- 1 file changed, 45 insertions(+), 33 deletions(-) diff --git a/archival/gzip.c b/archival/gzip.c index 0ef25727d..758c70a4b 100644 --- a/archival/gzip.c +++ b/archival/gzip.c @@ -1476,7 +1476,7 @@ static void ct_init(ush * attr, int *methodp) for (code = 0; code < 16; code++) { base_dist[code] = dist; for (n = 0; n < (1 << extra_dbits[code]); n++) { - dist_code[dist++] = (uch) code; + dist_code[dist++] = code; } } Assert(dist == 256, "ct_init: dist != 256"); @@ -1492,15 +1492,24 @@ static void ct_init(ush * attr, int *methodp) /* Construct the codes of the static literal tree */ for (bits = 0; bits <= MAX_BITS; bits++) bl_count[bits] = 0; + n = 0; - while (n <= 143) - static_ltree[n++].Len = 8, bl_count[8]++; - while (n <= 255) - static_ltree[n++].Len = 9, bl_count[9]++; - while (n <= 279) - static_ltree[n++].Len = 7, bl_count[7]++; - while (n <= 287) - static_ltree[n++].Len = 8, bl_count[8]++; + while (n <= 143) { + static_ltree[n++].Len = 8; + bl_count[8]++; + } + while (n <= 255) { + static_ltree[n++].Len = 9; + bl_count[9]++; + } + while (n <= 279) { + static_ltree[n++].Len = 7; + bl_count[7]++; + } + while (n <= 287) { + static_ltree[n++].Len = 8; + bl_count[8]++; + } /* Codes 286 and 287 do not exist, but we must include them in the * tree construction to get a canonical Huffman tree (longest code * all ones) @@ -1684,10 +1693,8 @@ static void gen_bitlen(tree_desc * desc) if (m > max_code) continue; if (tree[m].Len != (unsigned) bits) { - Trace((stderr, "code %d bits %d->%d\n", m, tree[m].Len, - bits)); - opt_len += - ((long) bits - (long) tree[m].Len) * (long) tree[m].Freq; + Trace((stderr, "code %d bits %d->%d\n", m, tree[m].Len, bits)); + opt_len += ((long) bits - (long) tree[m].Len) * (long) tree[m].Freq; tree[m].Len = (ush) bits; } n--; @@ -1846,8 +1853,10 @@ static void scan_tree(ct_data * tree, int max_code) int max_count = 7; /* max repeat count */ int min_count = 4; /* min repeat count */ - if (nextlen == 0) - max_count = 138, min_count = 3; + if (nextlen == 0) { + max_count = 138; + min_count = 3; + } tree[max_code + 1].Len = (ush) 0xffff; /* guard */ for (n = 0; n <= max_code; n++) { @@ -1869,11 +1878,14 @@ static void scan_tree(ct_data * tree, int max_code) count = 0; prevlen = curlen; if (nextlen == 0) { - max_count = 138, min_count = 3; + max_count = 138; + min_count = 3; } else if (curlen == nextlen) { - max_count = 6, min_count = 3; + max_count = 6; + min_count = 3; } else { - max_count = 7, min_count = 4; + max_count = 7; + min_count = 4; } } } @@ -1904,8 +1916,7 @@ static void send_tree(ct_data * tree, int max_code) } else if (count < min_count) { do { send_code(curlen, bl_tree); - } while (--count != 0); - + } while (--count); } else if (curlen != 0) { if (curlen != prevlen) { send_code(curlen, bl_tree); @@ -1914,11 +1925,9 @@ static void send_tree(ct_data * tree, int max_code) Assert(count >= 3 && count <= 6, " 3_6?"); send_code(REP_3_6, bl_tree); send_bits(count - 3, 2); - } else if (count <= 10) { send_code(REPZ_3_10, bl_tree); send_bits(count - 3, 3); - } else { send_code(REPZ_11_138, bl_tree); send_bits(count - 11, 7); @@ -1926,11 +1935,14 @@ static void send_tree(ct_data * tree, int max_code) count = 0; prevlen = curlen; if (nextlen == 0) { - max_count = 138, min_count = 3; + max_count = 138; + min_count = 3; } else if (curlen == nextlen) { - max_count = 6, min_count = 3; + max_count = 6; + min_count = 3; } else { - max_count = 7, min_count = 4; + max_count = 7; + min_count = 4; } } } @@ -2046,7 +2058,7 @@ static ulg flush_block(char *buf, ulg stored_len, int eof) */ if (stored_len <= opt_lenb && eof && compressed_len == 0L && seekable()) { /* Since LIT_BUFSIZE <= 2*WSIZE, the input data must be there: */ - if (buf == (char *) 0) + if (buf == NULL) bb_error_msg("block vanished"); copy_block(buf, (unsigned) stored_len, 0); /* without header */ @@ -2104,14 +2116,15 @@ static int ct_tally(int dist, int lc) } else { /* Here, lc is the match length - MIN_MATCH */ dist--; /* dist = match distance - 1 */ - Assert((ush) dist < (ush) MAX_DIST && - (ush) lc <= (ush) (MAX_MATCH - MIN_MATCH) && - (ush) d_code(dist) < (ush) D_CODES, "ct_tally: bad match"); + Assert((ush) dist < (ush) MAX_DIST + && (ush) lc <= (ush) (MAX_MATCH - MIN_MATCH) + && (ush) d_code(dist) < (ush) D_CODES, "ct_tally: bad match" + ); dyn_ltree[length_code[lc] + LITERALS + 1].Freq++; dyn_dtree[d_code(dist)].Freq++; - d_buf[last_dist++] = (ush) dist; + d_buf[last_dist++] = dist; flags |= flag_bit; } flag_bit <<= 1; @@ -2124,13 +2137,12 @@ static int ct_tally(int dist, int lc) /* Try to guess if it is profitable to stop the current block here */ if ((last_lit & 0xfff) == 0) { /* Compute an upper bound for the compressed length */ - ulg out_length = (ulg) last_lit * 8L; + ulg out_length = last_lit * 8L; ulg in_length = (ulg) strstart - block_start; int dcode; for (dcode = 0; dcode < D_CODES; dcode++) { - out_length += - (ulg) dyn_dtree[dcode].Freq * (5L + extra_dbits[dcode]); + out_length += dyn_dtree[dcode].Freq * (5L + extra_dbits[dcode]); } out_length >>= 3; Trace((stderr, -- 2.25.1