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-rw-r--r--src/Common/zlib/trees.c526
1 files changed, 224 insertions, 302 deletions
diff --git a/src/Common/zlib/trees.c b/src/Common/zlib/trees.c
index 5f305c47..8dbdc40b 100644
--- a/src/Common/zlib/trees.c
+++ b/src/Common/zlib/trees.c
@@ -122,39 +122,116 @@ struct static_tree_desc_s {
int max_length; /* max bit length for the codes */
};
-local const static_tree_desc static_l_desc =
+#ifdef NO_INIT_GLOBAL_POINTERS
+# define TCONST
+#else
+# define TCONST const
+#endif
+
+local TCONST static_tree_desc static_l_desc =
{static_ltree, extra_lbits, LITERALS+1, L_CODES, MAX_BITS};
-local const static_tree_desc static_d_desc =
+local TCONST static_tree_desc static_d_desc =
{static_dtree, extra_dbits, 0, D_CODES, MAX_BITS};
-local const static_tree_desc static_bl_desc =
+local TCONST static_tree_desc static_bl_desc =
{(const ct_data *)0, extra_blbits, 0, BL_CODES, MAX_BL_BITS};
/* ===========================================================================
- * Local (static) routines in this file.
+ * Output a short LSB first on the stream.
+ * IN assertion: there is enough room in pendingBuf.
+ */
+#define put_short(s, w) { \
+ put_byte(s, (uch)((w) & 0xff)); \
+ put_byte(s, (uch)((ush)(w) >> 8)); \
+}
+
+/* ===========================================================================
+ * Reverse the first len bits of a code, using straightforward code (a faster
+ * method would use a table)
+ * IN assertion: 1 <= len <= 15
*/
+local unsigned bi_reverse(unsigned code, int len) {
+ register unsigned res = 0;
+ do {
+ res |= code & 1;
+ code >>= 1, res <<= 1;
+ } while (--len > 0);
+ return res >> 1;
+}
-local void tr_static_init OF((void));
-local void init_block OF((deflate_state *s));
-local void pqdownheap OF((deflate_state *s, ct_data *tree, int k));
-local void gen_bitlen OF((deflate_state *s, tree_desc *desc));
-local void gen_codes OF((ct_data *tree, int max_code, ushf *bl_count));
-local void build_tree OF((deflate_state *s, tree_desc *desc));
-local void scan_tree OF((deflate_state *s, ct_data *tree, int max_code));
-local void send_tree OF((deflate_state *s, ct_data *tree, int max_code));
-local int build_bl_tree OF((deflate_state *s));
-local void send_all_trees OF((deflate_state *s, int lcodes, int dcodes,
- int blcodes));
-local void compress_block OF((deflate_state *s, const ct_data *ltree,
- const ct_data *dtree));
-local int detect_data_type OF((deflate_state *s));
-local unsigned bi_reverse OF((unsigned code, int len));
-local void bi_windup OF((deflate_state *s));
-local void bi_flush OF((deflate_state *s));
+/* ===========================================================================
+ * Flush the bit buffer, keeping at most 7 bits in it.
+ */
+local void bi_flush(deflate_state *s) {
+ if (s->bi_valid == 16) {
+ put_short(s, s->bi_buf);
+ s->bi_buf = 0;
+ s->bi_valid = 0;
+ } else if (s->bi_valid >= 8) {
+ put_byte(s, (Byte)s->bi_buf);
+ s->bi_buf >>= 8;
+ s->bi_valid -= 8;
+ }
+}
+
+/* ===========================================================================
+ * Flush the bit buffer and align the output on a byte boundary
+ */
+local void bi_windup(deflate_state *s) {
+ if (s->bi_valid > 8) {
+ put_short(s, s->bi_buf);
+ } else if (s->bi_valid > 0) {
+ put_byte(s, (Byte)s->bi_buf);
+ }
+ s->bi_buf = 0;
+ s->bi_valid = 0;
+#ifdef ZLIB_DEBUG
+ s->bits_sent = (s->bits_sent + 7) & ~7;
+#endif
+}
+
+/* ===========================================================================
+ * Generate the codes for a given tree and bit counts (which need not be
+ * optimal).
+ * IN assertion: the array bl_count contains the bit length statistics for
+ * the given tree and the field len is set for all tree elements.
+ * OUT assertion: the field code is set for all tree elements of non
+ * zero code length.
+ */
+local void gen_codes(ct_data *tree, int max_code, ushf *bl_count) {
+ ush next_code[MAX_BITS+1]; /* next code value for each bit length */
+ unsigned code = 0; /* running code value */
+ int bits; /* bit index */
+ int n; /* code index */
+
+ /* The distribution counts are first used to generate the code values
+ * without bit reversal.
+ */
+ for (bits = 1; bits <= MAX_BITS; bits++) {
+ code = (code + bl_count[bits - 1]) << 1;
+ next_code[bits] = (ush)code;
+ }
+ /* Check that the bit counts in bl_count are consistent. The last code
+ * must be all ones.
+ */
+ Assert (code + bl_count[MAX_BITS] - 1 == (1 << MAX_BITS) - 1,
+ "inconsistent bit counts");
+ Tracev((stderr,"\ngen_codes: max_code %d ", max_code));
+
+ for (n = 0; n <= max_code; n++) {
+ int len = tree[n].Len;
+ if (len == 0) continue;
+ /* Now reverse the bits */
+ tree[n].Code = (ush)bi_reverse(next_code[len]++, len);
+
+ Tracecv(tree != static_ltree, (stderr,"\nn %3d %c l %2d c %4x (%x) ",
+ n, (isgraph(n) ? n : ' '), len, tree[n].Code, next_code[len] - 1));
+ }
+}
#ifdef GEN_TREES_H
-local void gen_trees_header OF((void));
+local void gen_trees_header(void);
#endif
#ifndef ZLIB_DEBUG
@@ -168,26 +245,11 @@ local void gen_trees_header OF((void));
#endif
/* ===========================================================================
- * Output a short LSB first on the stream.
- * IN assertion: there is enough room in pendingBuf.
- */
-#define put_short(s, w) { \
- put_byte(s, (uch)((w) & 0xff)); \
- put_byte(s, (uch)((ush)(w) >> 8)); \
-}
-
-/* ===========================================================================
* Send a value on a given number of bits.
* IN assertion: length <= 16 and value fits in length bits.
*/
#ifdef ZLIB_DEBUG
-local void send_bits OF((deflate_state *s, int value, int length));
-
-local void send_bits(s, value, length)
- deflate_state *s;
- int value; /* value to send */
- int length; /* number of bits */
-{
+local void send_bits(deflate_state *s, int value, int length) {
Tracevv((stderr," l %2d v %4x ", length, value));
Assert(length > 0 && length <= 15, "invalid length");
s->bits_sent += (ulg)length;
@@ -229,8 +291,7 @@ local void send_bits(s, value, length)
/* ===========================================================================
* Initialize the various 'constant' tables.
*/
-local void tr_static_init()
-{
+local void tr_static_init(void) {
#if defined(GEN_TREES_H) || !defined(STDC)
static int static_init_done = 0;
int n; /* iterates over tree elements */
@@ -323,8 +384,7 @@ local void tr_static_init()
((i) == (last)? "\n};\n\n" : \
((i) % (width) == (width) - 1 ? ",\n" : ", "))
-void gen_trees_header()
-{
+void gen_trees_header(void) {
FILE *header = fopen("trees.h", "w");
int i;
@@ -374,11 +434,25 @@ void gen_trees_header()
#endif /* GEN_TREES_H */
/* ===========================================================================
+ * Initialize a new block.
+ */
+local void init_block(deflate_state *s) {
+ int n; /* iterates over tree elements */
+
+ /* Initialize the trees. */
+ for (n = 0; n < L_CODES; n++) s->dyn_ltree[n].Freq = 0;
+ for (n = 0; n < D_CODES; n++) s->dyn_dtree[n].Freq = 0;
+ for (n = 0; n < BL_CODES; n++) s->bl_tree[n].Freq = 0;
+
+ s->dyn_ltree[END_BLOCK].Freq = 1;
+ s->opt_len = s->static_len = 0L;
+ s->sym_next = s->matches = 0;
+}
+
+/* ===========================================================================
* Initialize the tree data structures for a new zlib stream.
*/
-void ZLIB_INTERNAL _tr_init(s)
- deflate_state *s;
-{
+void ZLIB_INTERNAL _tr_init(deflate_state *s) {
tr_static_init();
s->l_desc.dyn_tree = s->dyn_ltree;
@@ -401,24 +475,6 @@ void ZLIB_INTERNAL _tr_init(s)
init_block(s);
}
-/* ===========================================================================
- * Initialize a new block.
- */
-local void init_block(s)
- deflate_state *s;
-{
- int n; /* iterates over tree elements */
-
- /* Initialize the trees. */
- for (n = 0; n < L_CODES; n++) s->dyn_ltree[n].Freq = 0;
- for (n = 0; n < D_CODES; n++) s->dyn_dtree[n].Freq = 0;
- for (n = 0; n < BL_CODES; n++) s->bl_tree[n].Freq = 0;
-
- s->dyn_ltree[END_BLOCK].Freq = 1;
- s->opt_len = s->static_len = 0L;
- s->sym_next = s->matches = 0;
-}
-
#define SMALLEST 1
/* Index within the heap array of least frequent node in the Huffman tree */
@@ -448,11 +504,7 @@ local void init_block(s)
* when the heap property is re-established (each father smaller than its
* two sons).
*/
-local void pqdownheap(s, tree, k)
- deflate_state *s;
- ct_data *tree; /* the tree to restore */
- int k; /* node to move down */
-{
+local void pqdownheap(deflate_state *s, ct_data *tree, int k) {
int v = s->heap[k];
int j = k << 1; /* left son of k */
while (j <= s->heap_len) {
@@ -483,10 +535,7 @@ local void pqdownheap(s, tree, k)
* The length opt_len is updated; static_len is also updated if stree is
* not null.
*/
-local void gen_bitlen(s, desc)
- deflate_state *s;
- tree_desc *desc; /* the tree descriptor */
-{
+local void gen_bitlen(deflate_state *s, tree_desc *desc) {
ct_data *tree = desc->dyn_tree;
int max_code = desc->max_code;
const ct_data *stree = desc->stat_desc->static_tree;
@@ -561,48 +610,9 @@ local void gen_bitlen(s, desc)
}
}
-/* ===========================================================================
- * Generate the codes for a given tree and bit counts (which need not be
- * optimal).
- * IN assertion: the array bl_count contains the bit length statistics for
- * the given tree and the field len is set for all tree elements.
- * OUT assertion: the field code is set for all tree elements of non
- * zero code length.
- */
-local void gen_codes(tree, max_code, bl_count)
- ct_data *tree; /* the tree to decorate */
- int max_code; /* largest code with non zero frequency */
- ushf *bl_count; /* number of codes at each bit length */
-{
- ush next_code[MAX_BITS+1]; /* next code value for each bit length */
- unsigned code = 0; /* running code value */
- int bits; /* bit index */
- int n; /* code index */
-
- /* The distribution counts are first used to generate the code values
- * without bit reversal.
- */
- for (bits = 1; bits <= MAX_BITS; bits++) {
- code = (code + bl_count[bits - 1]) << 1;
- next_code[bits] = (ush)code;
- }
- /* Check that the bit counts in bl_count are consistent. The last code
- * must be all ones.
- */
- Assert (code + bl_count[MAX_BITS] - 1 == (1 << MAX_BITS) - 1,
- "inconsistent bit counts");
- Tracev((stderr,"\ngen_codes: max_code %d ", max_code));
-
- for (n = 0; n <= max_code; n++) {
- int len = tree[n].Len;
- if (len == 0) continue;
- /* Now reverse the bits */
- tree[n].Code = (ush)bi_reverse(next_code[len]++, len);
-
- Tracecv(tree != static_ltree, (stderr,"\nn %3d %c l %2d c %4x (%x) ",
- n, (isgraph(n) ? n : ' '), len, tree[n].Code, next_code[len] - 1));
- }
-}
+#ifdef DUMP_BL_TREE
+# include <stdio.h>
+#endif
/* ===========================================================================
* Construct one Huffman tree and assigns the code bit strings and lengths.
@@ -612,10 +622,7 @@ local void gen_codes(tree, max_code, bl_count)
* and corresponding code. The length opt_len is updated; static_len is
* also updated if stree is not null. The field max_code is set.
*/
-local void build_tree(s, desc)
- deflate_state *s;
- tree_desc *desc; /* the tree descriptor */
-{
+local void build_tree(deflate_state *s, tree_desc *desc) {
ct_data *tree = desc->dyn_tree;
const ct_data *stree = desc->stat_desc->static_tree;
int elems = desc->stat_desc->elems;
@@ -700,11 +707,7 @@ local void build_tree(s, desc)
* Scan a literal or distance tree to determine the frequencies of the codes
* in the bit length tree.
*/
-local void scan_tree(s, tree, max_code)
- deflate_state *s;
- ct_data *tree; /* the tree to be scanned */
- int max_code; /* and its largest code of non zero frequency */
-{
+local void scan_tree(deflate_state *s, ct_data *tree, int max_code) {
int n; /* iterates over all tree elements */
int prevlen = -1; /* last emitted length */
int curlen; /* length of current code */
@@ -745,11 +748,7 @@ local void scan_tree(s, tree, max_code)
* Send a literal or distance tree in compressed form, using the codes in
* bl_tree.
*/
-local void send_tree(s, tree, max_code)
- deflate_state *s;
- ct_data *tree; /* the tree to be scanned */
- int max_code; /* and its largest code of non zero frequency */
-{
+local void send_tree(deflate_state *s, ct_data *tree, int max_code) {
int n; /* iterates over all tree elements */
int prevlen = -1; /* last emitted length */
int curlen; /* length of current code */
@@ -796,9 +795,7 @@ local void send_tree(s, tree, max_code)
* Construct the Huffman tree for the bit lengths and return the index in
* bl_order of the last bit length code to send.
*/
-local int build_bl_tree(s)
- deflate_state *s;
-{
+local int build_bl_tree(deflate_state *s) {
int max_blindex; /* index of last bit length code of non zero freq */
/* Determine the bit length frequencies for literal and distance trees */
@@ -831,10 +828,8 @@ local int build_bl_tree(s)
* lengths of the bit length codes, the literal tree and the distance tree.
* IN assertion: lcodes >= 257, dcodes >= 1, blcodes >= 4.
*/
-local void send_all_trees(s, lcodes, dcodes, blcodes)
- deflate_state *s;
- int lcodes, dcodes, blcodes; /* number of codes for each tree */
-{
+local void send_all_trees(deflate_state *s, int lcodes, int dcodes,
+ int blcodes) {
int rank; /* index in bl_order */
Assert (lcodes >= 257 && dcodes >= 1 && blcodes >= 4, "not enough codes");
@@ -860,12 +855,8 @@ local void send_all_trees(s, lcodes, dcodes, blcodes)
/* ===========================================================================
* Send a stored block
*/
-void ZLIB_INTERNAL _tr_stored_block(s, buf, stored_len, last)
- deflate_state *s;
- charf *buf; /* input block */
- ulg stored_len; /* length of input block */
- int last; /* one if this is the last block for a file */
-{
+void ZLIB_INTERNAL _tr_stored_block(deflate_state *s, charf *buf,
+ ulg stored_len, int last) {
send_bits(s, (STORED_BLOCK<<1) + last, 3); /* send block type */
bi_windup(s); /* align on byte boundary */
put_short(s, (ush)stored_len);
@@ -884,9 +875,7 @@ void ZLIB_INTERNAL _tr_stored_block(s, buf, stored_len, last)
/* ===========================================================================
* Flush the bits in the bit buffer to pending output (leaves at most 7 bits)
*/
-void ZLIB_INTERNAL _tr_flush_bits(s)
- deflate_state *s;
-{
+void ZLIB_INTERNAL _tr_flush_bits(deflate_state *s) {
bi_flush(s);
}
@@ -894,9 +883,7 @@ void ZLIB_INTERNAL _tr_flush_bits(s)
* Send one empty static block to give enough lookahead for inflate.
* This takes 10 bits, of which 7 may remain in the bit buffer.
*/
-void ZLIB_INTERNAL _tr_align(s)
- deflate_state *s;
-{
+void ZLIB_INTERNAL _tr_align(deflate_state *s) {
send_bits(s, STATIC_TREES<<1, 3);
send_code(s, END_BLOCK, static_ltree);
#ifdef ZLIB_DEBUG
@@ -906,15 +893,98 @@ void ZLIB_INTERNAL _tr_align(s)
}
/* ===========================================================================
+ * Send the block data compressed using the given Huffman trees
+ */
+local void compress_block(deflate_state *s, const ct_data *ltree,
+ const ct_data *dtree) {
+ unsigned dist; /* distance of matched string */
+ int lc; /* match length or unmatched char (if dist == 0) */
+ unsigned sx = 0; /* running index in sym_buf */
+ unsigned code; /* the code to send */
+ int extra; /* number of extra bits to send */
+
+ 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));
+ } else {
+ /* Here, lc is the match length - MIN_MATCH */
+ code = _length_code[lc];
+ send_code(s, code + LITERALS + 1, ltree); /* send length code */
+ extra = extra_lbits[code];
+ if (extra != 0) {
+ lc -= base_length[code];
+ send_bits(s, lc, extra); /* send the extra length bits */
+ }
+ dist--; /* dist is now the match distance - 1 */
+ code = d_code(dist);
+ Assert (code < D_CODES, "bad d_code");
+
+ send_code(s, code, dtree); /* send the distance code */
+ extra = extra_dbits[code];
+ if (extra != 0) {
+ dist -= (unsigned)base_dist[code];
+ send_bits(s, dist, extra); /* send the extra distance bits */
+ }
+ } /* literal or match pair ? */
+
+ /* Check that the overlay between pending_buf and sym_buf is ok: */
+ Assert(s->pending < s->lit_bufsize + sx, "pendingBuf overflow");
+
+ } while (sx < s->sym_next);
+
+ send_code(s, END_BLOCK, ltree);
+}
+
+/* ===========================================================================
+ * Check if the data type is TEXT or BINARY, using the following algorithm:
+ * - TEXT if the two conditions below are satisfied:
+ * a) There are no non-portable control characters belonging to the
+ * "block list" (0..6, 14..25, 28..31).
+ * b) There is at least one printable character belonging to the
+ * "allow list" (9 {TAB}, 10 {LF}, 13 {CR}, 32..255).
+ * - BINARY otherwise.
+ * - The following partially-portable control characters form a
+ * "gray list" that is ignored in this detection algorithm:
+ * (7 {BEL}, 8 {BS}, 11 {VT}, 12 {FF}, 26 {SUB}, 27 {ESC}).
+ * IN assertion: the fields Freq of dyn_ltree are set.
+ */
+local int detect_data_type(deflate_state *s) {
+ /* block_mask is the bit mask of block-listed bytes
+ * set bits 0..6, 14..25, and 28..31
+ * 0xf3ffc07f = binary 11110011111111111100000001111111
+ */
+ unsigned long block_mask = 0xf3ffc07fUL;
+ int n;
+
+ /* Check for non-textual ("block-listed") bytes. */
+ for (n = 0; n <= 31; n++, block_mask >>= 1)
+ if ((block_mask & 1) && (s->dyn_ltree[n].Freq != 0))
+ return Z_BINARY;
+
+ /* Check for textual ("allow-listed") bytes. */
+ if (s->dyn_ltree[9].Freq != 0 || s->dyn_ltree[10].Freq != 0
+ || s->dyn_ltree[13].Freq != 0)
+ return Z_TEXT;
+ for (n = 32; n < LITERALS; n++)
+ if (s->dyn_ltree[n].Freq != 0)
+ return Z_TEXT;
+
+ /* There are no "block-listed" or "allow-listed" bytes:
+ * this stream either is empty or has tolerated ("gray-listed") bytes only.
+ */
+ return Z_BINARY;
+}
+
+/* ===========================================================================
* Determine the best encoding for the current block: dynamic trees, static
* trees or store, and write out the encoded block.
*/
-void ZLIB_INTERNAL _tr_flush_block(s, buf, stored_len, last)
- deflate_state *s;
- charf *buf; /* input block, or NULL if too old */
- ulg stored_len; /* length of input block */
- int last; /* one if this is the last block for a file */
-{
+void ZLIB_INTERNAL _tr_flush_block(deflate_state *s, charf *buf,
+ ulg stored_len, int last) {
ulg opt_lenb, static_lenb; /* opt_len and static_len in bytes */
int max_blindex = 0; /* index of last bit length code of non zero freq */
@@ -1011,11 +1081,7 @@ void ZLIB_INTERNAL _tr_flush_block(s, buf, stored_len, last)
* Save the match info and tally the frequency counts. Return true if
* the current block must be flushed.
*/
-int ZLIB_INTERNAL _tr_tally(s, dist, lc)
- deflate_state *s;
- unsigned dist; /* distance of matched string */
- unsigned lc; /* match length - MIN_MATCH or unmatched char (dist==0) */
-{
+int ZLIB_INTERNAL _tr_tally(deflate_state *s, unsigned dist, unsigned lc) {
s->sym_buf[s->sym_next++] = (uch)dist;
s->sym_buf[s->sym_next++] = (uch)(dist >> 8);
s->sym_buf[s->sym_next++] = (uch)lc;
@@ -1035,147 +1101,3 @@ int ZLIB_INTERNAL _tr_tally(s, dist, lc)
}
return (s->sym_next == s->sym_end);
}
-
-/* ===========================================================================
- * Send the block data compressed using the given Huffman trees
- */
-local void compress_block(s, ltree, dtree)
- deflate_state *s;
- const ct_data *ltree; /* literal tree */
- const ct_data *dtree; /* distance tree */
-{
- unsigned dist; /* distance of matched string */
- int lc; /* match length or unmatched char (if dist == 0) */
- unsigned sx = 0; /* running index in sym_buf */
- unsigned code; /* the code to send */
- int extra; /* number of extra bits to send */
-
- 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));
- } else {
- /* Here, lc is the match length - MIN_MATCH */
- code = _length_code[lc];
- send_code(s, code + LITERALS + 1, ltree); /* send length code */
- extra = extra_lbits[code];
- if (extra != 0) {
- lc -= base_length[code];
- send_bits(s, lc, extra); /* send the extra length bits */
- }
- dist--; /* dist is now the match distance - 1 */
- code = d_code(dist);
- Assert (code < D_CODES, "bad d_code");
-
- send_code(s, code, dtree); /* send the distance code */
- extra = extra_dbits[code];
- if (extra != 0) {
- dist -= (unsigned)base_dist[code];
- send_bits(s, dist, extra); /* send the extra distance bits */
- }
- } /* literal or match pair ? */
-
- /* Check that the overlay between pending_buf and sym_buf is ok: */
- Assert(s->pending < s->lit_bufsize + sx, "pendingBuf overflow");
-
- } while (sx < s->sym_next);
-
- send_code(s, END_BLOCK, ltree);
-}
-
-/* ===========================================================================
- * Check if the data type is TEXT or BINARY, using the following algorithm:
- * - TEXT if the two conditions below are satisfied:
- * a) There are no non-portable control characters belonging to the
- * "block list" (0..6, 14..25, 28..31).
- * b) There is at least one printable character belonging to the
- * "allow list" (9 {TAB}, 10 {LF}, 13 {CR}, 32..255).
- * - BINARY otherwise.
- * - The following partially-portable control characters form a
- * "gray list" that is ignored in this detection algorithm:
- * (7 {BEL}, 8 {BS}, 11 {VT}, 12 {FF}, 26 {SUB}, 27 {ESC}).
- * IN assertion: the fields Freq of dyn_ltree are set.
- */
-local int detect_data_type(s)
- deflate_state *s;
-{
- /* block_mask is the bit mask of block-listed bytes
- * set bits 0..6, 14..25, and 28..31
- * 0xf3ffc07f = binary 11110011111111111100000001111111
- */
- unsigned long block_mask = 0xf3ffc07fUL;
- int n;
-
- /* Check for non-textual ("block-listed") bytes. */
- for (n = 0; n <= 31; n++, block_mask >>= 1)
- if ((block_mask & 1) && (s->dyn_ltree[n].Freq != 0))
- return Z_BINARY;
-
- /* Check for textual ("allow-listed") bytes. */
- if (s->dyn_ltree[9].Freq != 0 || s->dyn_ltree[10].Freq != 0
- || s->dyn_ltree[13].Freq != 0)
- return Z_TEXT;
- for (n = 32; n < LITERALS; n++)
- if (s->dyn_ltree[n].Freq != 0)
- return Z_TEXT;
-
- /* There are no "block-listed" or "allow-listed" bytes:
- * this stream either is empty or has tolerated ("gray-listed") bytes only.
- */
- return Z_BINARY;
-}
-
-/* ===========================================================================
- * Reverse the first len bits of a code, using straightforward code (a faster
- * method would use a table)
- * IN assertion: 1 <= len <= 15
- */
-local unsigned bi_reverse(code, len)
- unsigned code; /* the value to invert */
- int len; /* its bit length */
-{
- register unsigned res = 0;
- do {
- res |= code & 1;
- code >>= 1, res <<= 1;
- } while (--len > 0);
- return res >> 1;
-}
-
-/* ===========================================================================
- * Flush the bit buffer, keeping at most 7 bits in it.
- */
-local void bi_flush(s)
- deflate_state *s;
-{
- if (s->bi_valid == 16) {
- put_short(s, s->bi_buf);
- s->bi_buf = 0;
- s->bi_valid = 0;
- } else if (s->bi_valid >= 8) {
- put_byte(s, (Byte)s->bi_buf);
- s->bi_buf >>= 8;
- s->bi_valid -= 8;
- }
-}
-
-/* ===========================================================================
- * Flush the bit buffer and align the output on a byte boundary
- */
-local void bi_windup(s)
- deflate_state *s;
-{
- if (s->bi_valid > 8) {
- put_short(s, s->bi_buf);
- } else if (s->bi_valid > 0) {
- put_byte(s, (Byte)s->bi_buf);
- }
- s->bi_buf = 0;
- s->bi_valid = 0;
-#ifdef ZLIB_DEBUG
- s->bits_sent = (s->bits_sent + 7) & ~7;
-#endif
-}