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authorPaul Sokolovsky <pfalcon@users.sourceforge.net>2016-08-17 06:00:28 +0300
committerPaul Sokolovsky <pfalcon@users.sourceforge.net>2016-08-17 06:06:33 +0300
commitff1c2b03a90af57589e29d17f8846961b9bdae95 (patch)
treedefd88b571474d85de37e630db044c8e5faf4125 /extmod
parentbb19e7b94bd8cc69b75e6d39dd9f2ec6e0cebba6 (diff)
downloadmicropython-ff1c2b03a90af57589e29d17f8846961b9bdae95.tar.gz
micropython-ff1c2b03a90af57589e29d17f8846961b9bdae95.zip
extmod/uzlib/: Update uzlib to v2.0.
New API supporting stream decompression.
Diffstat (limited to 'extmod')
-rw-r--r--extmod/uzlib/adler32.c6
-rw-r--r--extmod/uzlib/crc32.c63
-rw-r--r--extmod/uzlib/tinf.h78
-rw-r--r--extmod/uzlib/tinflate.c375
-rw-r--r--extmod/uzlib/tinfzlib.c53
5 files changed, 323 insertions, 252 deletions
diff --git a/extmod/uzlib/adler32.c b/extmod/uzlib/adler32.c
index f99b2d7f40..b06a7b37cc 100644
--- a/extmod/uzlib/adler32.c
+++ b/extmod/uzlib/adler32.c
@@ -41,12 +41,12 @@
#define A32_BASE 65521
#define A32_NMAX 5552
-unsigned int tinf_adler32(const void *data, unsigned int length)
+unsigned int uzlib_adler32(const void *data, unsigned int length, unsigned int prev_sum /* 1 */)
{
const unsigned char *buf = (const unsigned char *)data;
- unsigned int s1 = 1;
- unsigned int s2 = 0;
+ unsigned int s1 = prev_sum & 0xffff;
+ unsigned int s2 = prev_sum >> 16;
while (length > 0)
{
diff --git a/extmod/uzlib/crc32.c b/extmod/uzlib/crc32.c
new file mode 100644
index 0000000000..8c9976594d
--- /dev/null
+++ b/extmod/uzlib/crc32.c
@@ -0,0 +1,63 @@
+/*
+ * CRC32 checksum
+ *
+ * Copyright (c) 1998-2003 by Joergen Ibsen / Jibz
+ * All Rights Reserved
+ *
+ * http://www.ibsensoftware.com/
+ *
+ * This software is provided 'as-is', without any express
+ * or implied warranty. In no event will the authors be
+ * held liable for any damages arising from the use of
+ * this software.
+ *
+ * Permission is granted to anyone to use this software
+ * for any purpose, including commercial applications,
+ * and to alter it and redistribute it freely, subject to
+ * the following restrictions:
+ *
+ * 1. The origin of this software must not be
+ * misrepresented; you must not claim that you
+ * wrote the original software. If you use this
+ * software in a product, an acknowledgment in
+ * the product documentation would be appreciated
+ * but is not required.
+ *
+ * 2. Altered source versions must be plainly marked
+ * as such, and must not be misrepresented as
+ * being the original software.
+ *
+ * 3. This notice may not be removed or altered from
+ * any source distribution.
+ */
+
+/*
+ * CRC32 algorithm taken from the zlib source, which is
+ * Copyright (C) 1995-1998 Jean-loup Gailly and Mark Adler
+ */
+
+#include "tinf.h"
+
+static const unsigned int tinf_crc32tab[16] = {
+ 0x00000000, 0x1db71064, 0x3b6e20c8, 0x26d930ac, 0x76dc4190,
+ 0x6b6b51f4, 0x4db26158, 0x5005713c, 0xedb88320, 0xf00f9344,
+ 0xd6d6a3e8, 0xcb61b38c, 0x9b64c2b0, 0x86d3d2d4, 0xa00ae278,
+ 0xbdbdf21c
+};
+
+/* crc is previous value for incremental computation, 0xffffffff initially */
+unsigned int uzlib_crc32(const void *data, unsigned int length, unsigned int crc)
+{
+ const unsigned char *buf = (const unsigned char *)data;
+ unsigned int i;
+
+ for (i = 0; i < length; ++i)
+ {
+ crc ^= buf[i];
+ crc = tinf_crc32tab[crc & 0x0f] ^ (crc >> 4);
+ crc = tinf_crc32tab[crc & 0x0f] ^ (crc >> 4);
+ }
+
+ // return value suitable for passing in next time, for final value invert it
+ return crc/* ^ 0xffffffff*/;
+}
diff --git a/extmod/uzlib/tinf.h b/extmod/uzlib/tinf.h
index e9401f2de5..3545bbd883 100644
--- a/extmod/uzlib/tinf.h
+++ b/extmod/uzlib/tinf.h
@@ -5,7 +5,7 @@
* All Rights Reserved
* http://www.ibsensoftware.com/
*
- * Copyright (c) 2014 by Paul Sokolovsky
+ * Copyright (c) 2014-2016 by Paul Sokolovsky
*/
#ifndef TINF_H_INCLUDED
@@ -26,9 +26,17 @@
extern "C" {
#endif
+/* ok status, more data produced */
#define TINF_OK 0
+/* end of compressed stream reached */
+#define TINF_DONE 1
#define TINF_DATA_ERROR (-3)
-#define TINF_DEST_OVERFLOW (-4)
+#define TINF_CHKSUM_ERROR (-4)
+
+/* checksum types */
+#define TINF_CHKSUM_NONE 0
+#define TINF_CHKSUM_ADLER 1
+#define TINF_CHKSUM_CRC 2
/* data structures */
@@ -40,6 +48,10 @@ typedef struct {
struct TINF_DATA;
typedef struct TINF_DATA {
const unsigned char *source;
+ /* If source above is NULL, this function will be used to read
+ next byte from source stream */
+ unsigned char (*readSource)(struct TINF_DATA *data);
+
unsigned int tag;
unsigned int bitcount;
@@ -51,49 +63,51 @@ typedef struct TINF_DATA {
unsigned char *dest;
/* Remaining bytes in buffer */
unsigned int destRemaining;
- /* Argument is the allocation size which didn't fit into buffer. Note that
- exact mimumum size to grow buffer by is lastAlloc - destRemaining. But
- growing by this exact size is ineficient, as the next allocation will
- fail again. */
- int (*destGrow)(struct TINF_DATA *data, unsigned int lastAlloc);
+
+ /* Accumulating checksum */
+ unsigned int checksum;
+ char checksum_type;
+
+ int btype;
+ int bfinal;
+ unsigned int curlen;
+ int lzOff;
+ unsigned char *dict_ring;
+ unsigned int dict_size;
+ unsigned int dict_idx;
TINF_TREE ltree; /* dynamic length/symbol tree */
TINF_TREE dtree; /* dynamic distance tree */
} TINF_DATA;
+#define TINF_PUT(d, c) \
+ { \
+ *d->dest++ = c; \
+ if (d->dict_ring) { d->dict_ring[d->dict_idx++] = c; if (d->dict_idx == d->dict_size) d->dict_idx = 0; } \
+ }
-/* low-level API */
-
-/* Step 1: Allocate TINF_DATA structure */
-/* Step 2: Set destStart, destSize, and destGrow fields */
-/* Step 3: Set source field */
-/* Step 4: Call tinf_uncompress_dyn() */
-/* Step 5: In response to destGrow callback, update destStart and destSize fields */
-/* Step 6: When tinf_uncompress_dyn() returns, buf.dest points to a byte past last uncompressed byte */
-
-int TINFCC tinf_uncompress_dyn(TINF_DATA *d);
-int TINFCC tinf_zlib_uncompress_dyn(TINF_DATA *d, unsigned int sourceLen);
-
-/* high-level API */
-
-void TINFCC tinf_init(void);
+unsigned char TINFCC uzlib_get_byte(TINF_DATA *d);
-int TINFCC tinf_uncompress(void *dest, unsigned int *destLen,
- const void *source, unsigned int sourceLen);
+/* Decompression API */
-int TINFCC tinf_gzip_uncompress(void *dest, unsigned int *destLen,
- const void *source, unsigned int sourceLen);
+void TINFCC uzlib_init(void);
+void TINFCC uzlib_uncompress_init(TINF_DATA *d, void *dict, unsigned int dictLen);
+int TINFCC uzlib_uncompress(TINF_DATA *d);
+int TINFCC uzlib_uncompress_chksum(TINF_DATA *d);
-int TINFCC tinf_zlib_uncompress(void *dest, unsigned int *destLen,
- const void *source, unsigned int sourceLen);
+int TINFCC uzlib_zlib_parse_header(TINF_DATA *d);
+int TINFCC uzlib_gzip_parse_header(TINF_DATA *d);
-unsigned int TINFCC tinf_adler32(const void *data, unsigned int length);
+/* Compression API */
-unsigned int TINFCC tinf_crc32(const void *data, unsigned int length);
+void TINFCC uzlib_compress(void *data, const uint8_t *src, unsigned slen);
-/* compression API */
+/* Checksum API */
-void TINFCC tinf_compress(void *data, const uint8_t *src, unsigned slen);
+/* prev_sum is previous value for incremental computation, 1 initially */
+uint32_t TINFCC uzlib_adler32(const void *data, unsigned int length, uint32_t prev_sum);
+/* crc is previous value for incremental computation, 0xffffffff initially */
+uint32_t TINFCC uzlib_crc32(const void *data, unsigned int length, uint32_t crc);
#ifdef __cplusplus
} /* extern "C" */
diff --git a/extmod/uzlib/tinflate.c b/extmod/uzlib/tinflate.c
index faf27e5739..47644bfcb8 100644
--- a/extmod/uzlib/tinflate.c
+++ b/extmod/uzlib/tinflate.c
@@ -5,7 +5,7 @@
* All Rights Reserved
* http://www.ibsensoftware.com/
*
- * Copyright (c) 2014 by Paul Sokolovsky
+ * Copyright (c) 2014-2016 by Paul Sokolovsky
*
* This software is provided 'as-is', without any express
* or implied warranty. In no event will the authors be
@@ -32,6 +32,7 @@
* any source distribution.
*/
+#include <assert.h>
#include "tinf.h"
/* --------------------------------------------------- *
@@ -89,21 +90,6 @@ const unsigned char clcidx[] = {
* -- utility functions -- *
* ----------------------- */
-/* Execute callback to grow destination buffer */
-static int tinf_grow_dest_buf(TINF_DATA *d, unsigned int lastAlloc)
-{
- unsigned int oldsize = d->dest - d->destStart;
- /* This will update only destStart and destSize */
- if (!d->destGrow)
- {
- return TINF_DEST_OVERFLOW;
- }
- d->destGrow(d, lastAlloc);
- d->dest = d->destStart + oldsize;
- d->destRemaining = d->destSize - oldsize;
- return 0;
-}
-
#ifdef RUNTIME_BITS_TABLES
/* build extra bits and base tables */
static void tinf_build_bits_base(unsigned char *bits, unsigned short *base, int delta, int first)
@@ -180,6 +166,34 @@ static void tinf_build_tree(TINF_TREE *t, const unsigned char *lengths, unsigned
* -- decode functions -- *
* ---------------------- */
+unsigned char uzlib_get_byte(TINF_DATA *d)
+{
+ if (d->source) {
+ return *d->source++;
+ }
+ return d->readSource(d);
+}
+
+uint32_t tinf_get_le_uint32(TINF_DATA *d)
+{
+ uint32_t val = 0;
+ int i;
+ for (i = 4; i--;) {
+ val = val >> 8 | uzlib_get_byte(d) << 24;
+ }
+ return val;
+}
+
+uint32_t tinf_get_be_uint32(TINF_DATA *d)
+{
+ uint32_t val = 0;
+ int i;
+ for (i = 4; i--;) {
+ val = val << 8 | uzlib_get_byte(d);
+ }
+ return val;
+}
+
/* get one bit from source stream */
static int tinf_getbit(TINF_DATA *d)
{
@@ -189,7 +203,7 @@ static int tinf_getbit(TINF_DATA *d)
if (!d->bitcount--)
{
/* load next tag */
- d->tag = *d->source++;
+ d->tag = uzlib_get_byte(d);
d->bitcount = 7;
}
@@ -318,113 +332,83 @@ static void tinf_decode_trees(TINF_DATA *d, TINF_TREE *lt, TINF_TREE *dt)
/* given a stream and two trees, inflate a block of data */
static int tinf_inflate_block_data(TINF_DATA *d, TINF_TREE *lt, TINF_TREE *dt)
{
- while (1)
- {
- int sym = tinf_decode_symbol(d, lt);
-
- /* check for end of block */
- if (sym == 256)
- {
- return TINF_OK;
- }
-
- if (sym < 256)
- {
- if (d->destRemaining == 0)
- {
- int res = tinf_grow_dest_buf(d, 1);
- if (res) return res;
- }
-
- *d->dest++ = sym;
- d->destRemaining--;
-
- } else {
-
- unsigned int length, offs, i;
- int dist;
-
- sym -= 257;
-
- /* possibly get more bits from length code */
- length = tinf_read_bits(d, length_bits[sym], length_base[sym]);
-
- dist = tinf_decode_symbol(d, dt);
-
- /* possibly get more bits from distance code */
- offs = tinf_read_bits(d, dist_bits[dist], dist_base[dist]);
-
- if (d->destRemaining < length)
- {
- int res = tinf_grow_dest_buf(d, length);
- if (res) return res;
- }
-
- /* copy match */
- for (i = 0; i < length; ++i)
- {
- d->dest[i] = d->dest[(int)(i - offs)];
- }
-
- d->dest += length;
- d->destRemaining -= length;
- }
- }
+ if (d->curlen == 0) {
+ unsigned int offs;
+ int dist;
+ int sym = tinf_decode_symbol(d, lt);
+ //printf("huff sym: %02x\n", sym);
+
+ /* literal byte */
+ if (sym < 256) {
+ TINF_PUT(d, sym);
+ return TINF_OK;
+ }
+
+ /* end of block */
+ if (sym == 256) {
+ return TINF_DONE;
+ }
+
+ /* substring from sliding dictionary */
+ sym -= 257;
+ /* possibly get more bits from length code */
+ d->curlen = tinf_read_bits(d, length_bits[sym], length_base[sym]);
+
+ dist = tinf_decode_symbol(d, dt);
+ /* possibly get more bits from distance code */
+ offs = tinf_read_bits(d, dist_bits[dist], dist_base[dist]);
+ if (d->dict_ring) {
+ d->lzOff = d->dict_idx - offs;
+ if (d->lzOff < 0) {
+ d->lzOff += d->dict_size;
+ }
+ } else {
+ d->lzOff = -offs;
+ }
+ }
+
+ /* copy next byte from dict substring */
+ if (d->dict_ring) {
+ TINF_PUT(d, d->dict_ring[d->lzOff]);
+ if (++d->lzOff == d->dict_size) {
+ d->lzOff = 0;
+ }
+ } else {
+ d->dest[0] = d->dest[d->lzOff];
+ d->dest++;
+ }
+ d->curlen--;
+ return TINF_OK;
}
/* inflate an uncompressed block of data */
static int tinf_inflate_uncompressed_block(TINF_DATA *d)
{
- unsigned int length, invlength;
- unsigned int i;
-
- /* get length */
- length = d->source[1];
- length = 256*length + d->source[0];
-
- /* get one's complement of length */
- invlength = d->source[3];
- invlength = 256*invlength + d->source[2];
-
- /* check length */
- if (length != (~invlength & 0x0000ffff)) return TINF_DATA_ERROR;
-
- if (d->destRemaining < length)
- {
- int res = tinf_grow_dest_buf(d, length);
- if (res) return res;
- }
-
- d->source += 4;
-
- /* copy block */
- for (i = length; i; --i) *d->dest++ = *d->source++;
- d->destRemaining -= length;
-
- /* make sure we start next block on a byte boundary */
- d->bitcount = 0;
-
- return TINF_OK;
-}
-
-/* inflate a block of data compressed with fixed huffman trees */
-static int tinf_inflate_fixed_block(TINF_DATA *d)
-{
- /* build fixed huffman trees */
- tinf_build_fixed_trees(&d->ltree, &d->dtree);
-
- /* decode block using fixed trees */
- return tinf_inflate_block_data(d, &d->ltree, &d->dtree);
-}
-
-/* inflate a block of data compressed with dynamic huffman trees */
-static int tinf_inflate_dynamic_block(TINF_DATA *d)
-{
- /* decode trees from stream */
- tinf_decode_trees(d, &d->ltree, &d->dtree);
-
- /* decode block using decoded trees */
- return tinf_inflate_block_data(d, &d->ltree, &d->dtree);
+ if (d->curlen == 0) {
+ unsigned int length, invlength;
+
+ /* get length */
+ length = uzlib_get_byte(d) + 256 * uzlib_get_byte(d);
+ /* get one's complement of length */
+ invlength = uzlib_get_byte(d) + 256 * uzlib_get_byte(d);
+ /* check length */
+ if (length != (~invlength & 0x0000ffff)) return TINF_DATA_ERROR;
+
+ /* increment length to properly return TINF_DONE below, without
+ producing data at the same time */
+ d->curlen = length + 1;
+
+ /* make sure we start next block on a byte boundary */
+ d->bitcount = 0;
+ }
+
+ if (--d->curlen == 0) {
+ return TINF_DONE;
+ }
+
+ unsigned char c = uzlib_get_byte(d);
+ TINF_PUT(d, c);
+ return TINF_OK;
}
/* ---------------------- *
@@ -432,7 +416,7 @@ static int tinf_inflate_dynamic_block(TINF_DATA *d)
* ---------------------- */
/* initialize global (static) data */
-void tinf_init(void)
+void uzlib_init(void)
{
#ifdef RUNTIME_BITS_TABLES
/* build extra bits and base tables */
@@ -445,72 +429,117 @@ void tinf_init(void)
#endif
}
-/* inflate stream from source to dest */
-int tinf_uncompress(void *dest, unsigned int *destLen,
- const void *source, unsigned int sourceLen)
+/* initialize decompression structure */
+void uzlib_uncompress_init(TINF_DATA *d, void *dict, unsigned int dictLen)
{
- (void)sourceLen;
- TINF_DATA d;
- int res;
-
- /* initialise data */
- d.source = (const unsigned char *)source;
-
- d.destStart = (unsigned char *)dest;
- d.destRemaining = *destLen;
- d.destSize = *destLen;
-
- res = tinf_uncompress_dyn(&d);
-
- *destLen = d.dest - d.destStart;
+ d->bitcount = 0;
+ d->bfinal = 0;
+ d->btype = -1;
+ d->dict_size = dictLen;
+ d->dict_ring = dict;
+ d->dict_idx = 0;
+ d->curlen = 0;
+}
- return res;
+/* inflate next byte of compressed stream */
+int uzlib_uncompress(TINF_DATA *d)
+{
+ do {
+ int res;
+
+ /* start a new block */
+ if (d->btype == -1) {
+next_blk:
+ /* read final block flag */
+ d->bfinal = tinf_getbit(d);
+ /* read block type (2 bits) */
+ d->btype = tinf_read_bits(d, 2, 0);
+
+ //printf("Started new block: type=%d final=%d\n", d->btype, d->bfinal);
+
+ if (d->btype == 1) {
+ /* build fixed huffman trees */
+ tinf_build_fixed_trees(&d->ltree, &d->dtree);
+ } else if (d->btype == 2) {
+ /* decode trees from stream */
+ tinf_decode_trees(d, &d->ltree, &d->dtree);
+ }
+ }
+
+ /* process current block */
+ switch (d->btype)
+ {
+ case 0:
+ /* decompress uncompressed block */
+ res = tinf_inflate_uncompressed_block(d);
+ break;
+ case 1:
+ case 2:
+ /* decompress block with fixed/dyanamic huffman trees */
+ /* trees were decoded previously, so it's the same routine for both */
+ res = tinf_inflate_block_data(d, &d->ltree, &d->dtree);
+ break;
+ default:
+ return TINF_DATA_ERROR;
+ }
+
+ if (res == TINF_DONE && !d->bfinal) {
+ /* the block has ended (without producing more data), but we
+ can't return without data, so start procesing next block */
+ goto next_blk;
+ }
+
+ if (res != TINF_OK) {
+ return res;
+ }
+
+ } while (--d->destSize);
+
+ return TINF_OK;
}
-/* inflate stream from source to dest */
-int tinf_uncompress_dyn(TINF_DATA *d)
+int uzlib_uncompress_chksum(TINF_DATA *d)
{
- int bfinal;
+ int res;
+ unsigned char *data = d->dest;
- /* initialise data */
- d->bitcount = 0;
+ res = uzlib_uncompress(d);
- d->dest = d->destStart;
- d->destRemaining = d->destSize;
+ if (res < 0) return res;
- do {
+ switch (d->checksum_type) {
- unsigned int btype;
- int res;
+ case TINF_CHKSUM_ADLER:
+ d->checksum = uzlib_adler32(data, d->dest - data, d->checksum);
+ break;
- /* read final block flag */
- bfinal = tinf_getbit(d);
+ case TINF_CHKSUM_CRC:
+ d->checksum = uzlib_crc32(data, d->dest - data, d->checksum);
+ break;
+ }
- /* read block type (2 bits) */
- btype = tinf_read_bits(d, 2, 0);
+ if (res == TINF_DONE) {
+ unsigned int val;
- /* decompress block */
- switch (btype)
- {
- case 0:
- /* decompress uncompressed block */
- res = tinf_inflate_uncompressed_block(d);
- break;
- case 1:
- /* decompress block with fixed huffman trees */
- res = tinf_inflate_fixed_block(d);
- break;
- case 2:
- /* decompress block with dynamic huffman trees */
- res = tinf_inflate_dynamic_block(d);
- break;
- default:
- return TINF_DATA_ERROR;
- }
+ switch (d->checksum_type) {
- if (res != TINF_OK) return TINF_DATA_ERROR;
+ case TINF_CHKSUM_ADLER:
+ val = tinf_get_be_uint32(d);
+ if (d->checksum != val) {
+ return TINF_CHKSUM_ERROR;
+ }
+ break;
- } while (!bfinal);
+ case TINF_CHKSUM_CRC:
+ val = tinf_get_le_uint32(d);
+ if (~d->checksum != val) {
+ return TINF_CHKSUM_ERROR;
+ }
+ // Uncompressed size. TODO: Check
+ val = tinf_get_le_uint32(d);
+ break;
+ }
+ }
- return TINF_OK;
+ return res;
}
diff --git a/extmod/uzlib/tinfzlib.c b/extmod/uzlib/tinfzlib.c
index dbacc1d9db..74fade3b9d 100644
--- a/extmod/uzlib/tinfzlib.c
+++ b/extmod/uzlib/tinfzlib.c
@@ -6,6 +6,8 @@
*
* http://www.ibsensoftware.com/
*
+ * Copyright (c) 2014-2016 by Paul Sokolovsky
+ *
* This software is provided 'as-is', without any express
* or implied warranty. In no event will the authors be
* held liable for any damages arising from the use of
@@ -33,35 +35,14 @@
#include "tinf.h"
-int tinf_zlib_uncompress(void *dest, unsigned int *destLen,
- const void *source, unsigned int sourceLen)
-{
- TINF_DATA d;
- int res;
-
- /* initialise data */
- d.source = (const unsigned char *)source;
-
- d.destStart = (unsigned char *)dest;
- d.destRemaining = *destLen;
-
- res = tinf_zlib_uncompress_dyn(&d, sourceLen);
-
- *destLen = d.dest - d.destStart;
-
- return res;
-}
-
-int tinf_zlib_uncompress_dyn(TINF_DATA *d, unsigned int sourceLen)
+int uzlib_zlib_parse_header(TINF_DATA *d)
{
- unsigned int a32;
- int res;
unsigned char cmf, flg;
/* -- get header bytes -- */
- cmf = d->source[0];
- flg = d->source[1];
+ cmf = uzlib_get_byte(d);
+ flg = uzlib_get_byte(d);
/* -- check format -- */
@@ -77,25 +58,9 @@ int tinf_zlib_uncompress_dyn(TINF_DATA *d, unsigned int sourceLen)
/* check there is no preset dictionary */
if (flg & 0x20) return TINF_DATA_ERROR;
- /* -- get adler32 checksum -- */
+ /* initialize for adler32 checksum */
+ d->checksum_type = TINF_CHKSUM_ADLER;
+ d->checksum = 1;
- a32 = d->source[sourceLen - 4];
- a32 = 256*a32 + d->source[sourceLen - 3];
- a32 = 256*a32 + d->source[sourceLen - 2];
- a32 = 256*a32 + d->source[sourceLen - 1];
-
- d->source += 2;
-
- /* -- inflate -- */
-
- res = tinf_uncompress_dyn(d);
-
- if (res != TINF_OK) return res;
-
- /* -- check adler32 checksum -- */
-
- if (a32 != tinf_adler32(d->destStart, d->dest - d->destStart)) return TINF_DATA_ERROR;
-
- return TINF_OK;
+ return cmf >> 4;
}
-