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-rw-r--r--src/3rdparty/zlib/src/crc32.c255
1 files changed, 94 insertions, 161 deletions
diff --git a/src/3rdparty/zlib/src/crc32.c b/src/3rdparty/zlib/src/crc32.c
index a1bdce5c23..6c38f5c04c 100644
--- a/src/3rdparty/zlib/src/crc32.c
+++ b/src/3rdparty/zlib/src/crc32.c
@@ -98,10 +98,6 @@
# endif
#endif
-/* Local functions. */
-local z_crc_t multmodp OF((z_crc_t a, z_crc_t b));
-local z_crc_t x2nmodp OF((z_off64_t n, unsigned k));
-
/* If available, use the ARM processor CRC32 instruction. */
#if defined(__aarch64__) && defined(__ARM_FEATURE_CRC32) && W == 8
# define ARMCRC32
@@ -114,9 +110,7 @@ local z_crc_t x2nmodp OF((z_off64_t n, unsigned k));
instruction, if one is available. This assumes that word_t is either 32 bits
or 64 bits.
*/
-local z_word_t byte_swap(word)
- z_word_t word;
-{
+local z_word_t byte_swap(z_word_t word) {
# if W == 8
return
(word & 0xff00000000000000) >> 56 |
@@ -137,24 +131,77 @@ local z_word_t byte_swap(word)
}
#endif
+#ifdef DYNAMIC_CRC_TABLE
+/* =========================================================================
+ * Table of powers of x for combining CRC-32s, filled in by make_crc_table()
+ * below.
+ */
+ local z_crc_t FAR x2n_table[32];
+#else
+/* =========================================================================
+ * Tables for byte-wise and braided CRC-32 calculations, and a table of powers
+ * of x for combining CRC-32s, all made by make_crc_table().
+ */
+# include "crc32.h"
+#endif
+
/* CRC polynomial. */
#define POLY 0xedb88320 /* p(x) reflected, with x^32 implied */
-#ifdef DYNAMIC_CRC_TABLE
+/*
+ Return a(x) multiplied by b(x) modulo p(x), where p(x) is the CRC polynomial,
+ reflected. For speed, this requires that a not be zero.
+ */
+local z_crc_t multmodp(z_crc_t a, z_crc_t b) {
+ z_crc_t m, p;
+
+ m = (z_crc_t)1 << 31;
+ p = 0;
+ for (;;) {
+ if (a & m) {
+ p ^= b;
+ if ((a & (m - 1)) == 0)
+ break;
+ }
+ m >>= 1;
+ b = b & 1 ? (b >> 1) ^ POLY : b >> 1;
+ }
+ return p;
+}
+
+/*
+ Return x^(n * 2^k) modulo p(x). Requires that x2n_table[] has been
+ initialized.
+ */
+local z_crc_t x2nmodp(z_off64_t n, unsigned k) {
+ z_crc_t p;
+
+ p = (z_crc_t)1 << 31; /* x^0 == 1 */
+ while (n) {
+ if (n & 1)
+ p = multmodp(x2n_table[k & 31], p);
+ n >>= 1;
+ k++;
+ }
+ return p;
+}
+#ifdef DYNAMIC_CRC_TABLE
+/* =========================================================================
+ * Build the tables for byte-wise and braided CRC-32 calculations, and a table
+ * of powers of x for combining CRC-32s.
+ */
local z_crc_t FAR crc_table[256];
-local z_crc_t FAR x2n_table[32];
-local void make_crc_table OF((void));
#ifdef W
local z_word_t FAR crc_big_table[256];
local z_crc_t FAR crc_braid_table[W][256];
local z_word_t FAR crc_braid_big_table[W][256];
- local void braid OF((z_crc_t [][256], z_word_t [][256], int, int));
+ local void braid(z_crc_t [][256], z_word_t [][256], int, int);
#endif
#ifdef MAKECRCH
- local void write_table OF((FILE *, const z_crc_t FAR *, int));
- local void write_table32hi OF((FILE *, const z_word_t FAR *, int));
- local void write_table64 OF((FILE *, const z_word_t FAR *, int));
+ local void write_table(FILE *, const z_crc_t FAR *, int);
+ local void write_table32hi(FILE *, const z_word_t FAR *, int);
+ local void write_table64(FILE *, const z_word_t FAR *, int);
#endif /* MAKECRCH */
/*
@@ -167,7 +214,6 @@ local void make_crc_table OF((void));
/* Definition of once functionality. */
typedef struct once_s once_t;
-local void once OF((once_t *, void (*)(void)));
/* Check for the availability of atomics. */
#if defined(__STDC__) && __STDC_VERSION__ >= 201112L && \
@@ -187,10 +233,7 @@ struct once_s {
invoke once() at the same time. The state must be a once_t initialized with
ONCE_INIT.
*/
-local void once(state, init)
- once_t *state;
- void (*init)(void);
-{
+local void once(once_t *state, void (*init)(void)) {
if (!atomic_load(&state->done)) {
if (atomic_flag_test_and_set(&state->begun))
while (!atomic_load(&state->done))
@@ -213,10 +256,7 @@ struct once_s {
/* Test and set. Alas, not atomic, but tries to minimize the period of
vulnerability. */
-local int test_and_set OF((int volatile *));
-local int test_and_set(flag)
- int volatile *flag;
-{
+local int test_and_set(int volatile *flag) {
int was;
was = *flag;
@@ -225,10 +265,7 @@ local int test_and_set(flag)
}
/* Run the provided init() function once. This is not thread-safe. */
-local void once(state, init)
- once_t *state;
- void (*init)(void);
-{
+local void once(once_t *state, void (*init)(void)) {
if (!state->done) {
if (test_and_set(&state->begun))
while (!state->done)
@@ -270,8 +307,7 @@ local once_t made = ONCE_INIT;
combinations of CRC register values and incoming bytes.
*/
-local void make_crc_table()
-{
+local void make_crc_table(void) {
unsigned i, j, n;
z_crc_t p;
@@ -438,11 +474,7 @@ local void make_crc_table()
Write the 32-bit values in table[0..k-1] to out, five per line in
hexadecimal separated by commas.
*/
-local void write_table(out, table, k)
- FILE *out;
- const z_crc_t FAR *table;
- int k;
-{
+local void write_table(FILE *out, const z_crc_t FAR *table, int k) {
int n;
for (n = 0; n < k; n++)
@@ -455,11 +487,7 @@ local void write_table(out, table, k)
Write the high 32-bits of each value in table[0..k-1] to out, five per line
in hexadecimal separated by commas.
*/
-local void write_table32hi(out, table, k)
-FILE *out;
-const z_word_t FAR *table;
-int k;
-{
+local void write_table32hi(FILE *out, const z_word_t FAR *table, int k) {
int n;
for (n = 0; n < k; n++)
@@ -475,11 +503,7 @@ int k;
bits. If not, then the type cast and format string can be adjusted
accordingly.
*/
-local void write_table64(out, table, k)
- FILE *out;
- const z_word_t FAR *table;
- int k;
-{
+local void write_table64(FILE *out, const z_word_t FAR *table, int k) {
int n;
for (n = 0; n < k; n++)
@@ -489,8 +513,7 @@ local void write_table64(out, table, k)
}
/* Actually do the deed. */
-int main()
-{
+int main(void) {
make_crc_table();
return 0;
}
@@ -502,12 +525,7 @@ int main()
Generate the little and big-endian braid tables for the given n and z_word_t
size w. Each array must have room for w blocks of 256 elements.
*/
-local void braid(ltl, big, n, w)
- z_crc_t ltl[][256];
- z_word_t big[][256];
- int n;
- int w;
-{
+local void braid(z_crc_t ltl[][256], z_word_t big[][256], int n, int w) {
int k;
z_crc_t i, p, q;
for (k = 0; k < w; k++) {
@@ -522,69 +540,13 @@ local void braid(ltl, big, n, w)
}
#endif
-#else /* !DYNAMIC_CRC_TABLE */
-/* ========================================================================
- * Tables for byte-wise and braided CRC-32 calculations, and a table of powers
- * of x for combining CRC-32s, all made by make_crc_table().
- */
-#include "crc32.h"
#endif /* DYNAMIC_CRC_TABLE */
-/* ========================================================================
- * Routines used for CRC calculation. Some are also required for the table
- * generation above.
- */
-
-/*
- Return a(x) multiplied by b(x) modulo p(x), where p(x) is the CRC polynomial,
- reflected. For speed, this requires that a not be zero.
- */
-local z_crc_t multmodp(a, b)
- z_crc_t a;
- z_crc_t b;
-{
- z_crc_t m, p;
-
- m = (z_crc_t)1 << 31;
- p = 0;
- for (;;) {
- if (a & m) {
- p ^= b;
- if ((a & (m - 1)) == 0)
- break;
- }
- m >>= 1;
- b = b & 1 ? (b >> 1) ^ POLY : b >> 1;
- }
- return p;
-}
-
-/*
- Return x^(n * 2^k) modulo p(x). Requires that x2n_table[] has been
- initialized.
- */
-local z_crc_t x2nmodp(n, k)
- z_off64_t n;
- unsigned k;
-{
- z_crc_t p;
-
- p = (z_crc_t)1 << 31; /* x^0 == 1 */
- while (n) {
- if (n & 1)
- p = multmodp(x2n_table[k & 31], p);
- n >>= 1;
- k++;
- }
- return p;
-}
-
/* =========================================================================
* This function can be used by asm versions of crc32(), and to force the
* generation of the CRC tables in a threaded application.
*/
-const z_crc_t FAR * ZEXPORT get_crc_table()
-{
+const z_crc_t FAR * ZEXPORT get_crc_table(void) {
#ifdef DYNAMIC_CRC_TABLE
once(&made, make_crc_table);
#endif /* DYNAMIC_CRC_TABLE */
@@ -610,11 +572,8 @@ const z_crc_t FAR * ZEXPORT get_crc_table()
#define Z_BATCH_ZEROS 0xa10d3d0c /* computed from Z_BATCH = 3990 */
#define Z_BATCH_MIN 800 /* fewest words in a final batch */
-unsigned long ZEXPORT crc32_z(crc, buf, len)
- unsigned long crc;
- const unsigned char FAR *buf;
- z_size_t len;
-{
+unsigned long ZEXPORT crc32_z(unsigned long crc, const unsigned char FAR *buf,
+ z_size_t len) {
z_crc_t val;
z_word_t crc1, crc2;
const z_word_t *word;
@@ -630,7 +589,7 @@ unsigned long ZEXPORT crc32_z(crc, buf, len)
#endif /* DYNAMIC_CRC_TABLE */
/* Pre-condition the CRC */
- crc ^= 0xffffffff;
+ crc = (~crc) & 0xffffffff;
/* Compute the CRC up to a word boundary. */
while (len && ((z_size_t)buf & 7) != 0) {
@@ -645,8 +604,8 @@ unsigned long ZEXPORT crc32_z(crc, buf, len)
len &= 7;
/* Do three interleaved CRCs to realize the throughput of one crc32x
- instruction per cycle. Each CRC is calcuated on Z_BATCH words. The three
- CRCs are combined into a single CRC after each set of batches. */
+ instruction per cycle. Each CRC is calculated on Z_BATCH words. The
+ three CRCs are combined into a single CRC after each set of batches. */
while (num >= 3 * Z_BATCH) {
crc1 = 0;
crc2 = 0;
@@ -714,18 +673,14 @@ unsigned long ZEXPORT crc32_z(crc, buf, len)
least-significant byte of the word as the first byte of data, without any pre
or post conditioning. This is used to combine the CRCs of each braid.
*/
-local z_crc_t crc_word(data)
- z_word_t data;
-{
+local z_crc_t crc_word(z_word_t data) {
int k;
for (k = 0; k < W; k++)
data = (data >> 8) ^ crc_table[data & 0xff];
return (z_crc_t)data;
}
-local z_word_t crc_word_big(data)
- z_word_t data;
-{
+local z_word_t crc_word_big(z_word_t data) {
int k;
for (k = 0; k < W; k++)
data = (data << 8) ^
@@ -736,11 +691,8 @@ local z_word_t crc_word_big(data)
#endif
/* ========================================================================= */
-unsigned long ZEXPORT crc32_z(crc, buf, len)
- unsigned long crc;
- const unsigned char FAR *buf;
- z_size_t len;
-{
+unsigned long ZEXPORT crc32_z(unsigned long crc, const unsigned char FAR *buf,
+ z_size_t len) {
/* Return initial CRC, if requested. */
if (buf == Z_NULL) return 0;
@@ -749,7 +701,7 @@ unsigned long ZEXPORT crc32_z(crc, buf, len)
#endif /* DYNAMIC_CRC_TABLE */
/* Pre-condition the CRC */
- crc ^= 0xffffffff;
+ crc = (~crc) & 0xffffffff;
#ifdef W
@@ -772,8 +724,8 @@ unsigned long ZEXPORT crc32_z(crc, buf, len)
words = (z_word_t const *)buf;
/* Do endian check at execution time instead of compile time, since ARM
- processors can change the endianess at execution time. If the
- compiler knows what the endianess will be, it can optimize out the
+ processors can change the endianness at execution time. If the
+ compiler knows what the endianness will be, it can optimize out the
check and the unused branch. */
endian = 1;
if (*(unsigned char *)&endian) {
@@ -1060,39 +1012,26 @@ unsigned long ZEXPORT crc32_z(crc, buf, len)
#endif
/* ========================================================================= */
-unsigned long ZEXPORT crc32(crc, buf, len)
- unsigned long crc;
- const unsigned char FAR *buf;
- uInt len;
-{
+unsigned long ZEXPORT crc32(unsigned long crc, const unsigned char FAR *buf,
+ uInt len) {
return crc32_z(crc, buf, len);
}
/* ========================================================================= */
-uLong ZEXPORT crc32_combine64(crc1, crc2, len2)
- uLong crc1;
- uLong crc2;
- z_off64_t len2;
-{
+uLong ZEXPORT crc32_combine64(uLong crc1, uLong crc2, z_off64_t len2) {
#ifdef DYNAMIC_CRC_TABLE
once(&made, make_crc_table);
#endif /* DYNAMIC_CRC_TABLE */
- return multmodp(x2nmodp(len2, 3), crc1) ^ crc2;
+ return multmodp(x2nmodp(len2, 3), crc1) ^ (crc2 & 0xffffffff);
}
/* ========================================================================= */
-uLong ZEXPORT crc32_combine(crc1, crc2, len2)
- uLong crc1;
- uLong crc2;
- z_off_t len2;
-{
- return crc32_combine64(crc1, crc2, len2);
+uLong ZEXPORT crc32_combine(uLong crc1, uLong crc2, z_off_t len2) {
+ return crc32_combine64(crc1, crc2, (z_off64_t)len2);
}
/* ========================================================================= */
-uLong ZEXPORT crc32_combine_gen64(len2)
- z_off64_t len2;
-{
+uLong ZEXPORT crc32_combine_gen64(z_off64_t len2) {
#ifdef DYNAMIC_CRC_TABLE
once(&made, make_crc_table);
#endif /* DYNAMIC_CRC_TABLE */
@@ -1100,17 +1039,11 @@ uLong ZEXPORT crc32_combine_gen64(len2)
}
/* ========================================================================= */
-uLong ZEXPORT crc32_combine_gen(len2)
- z_off_t len2;
-{
- return crc32_combine_gen64(len2);
+uLong ZEXPORT crc32_combine_gen(z_off_t len2) {
+ return crc32_combine_gen64((z_off64_t)len2);
}
/* ========================================================================= */
-uLong crc32_combine_op(crc1, crc2, op)
- uLong crc1;
- uLong crc2;
- uLong op;
-{
- return multmodp(op, crc1) ^ crc2;
+uLong ZEXPORT crc32_combine_op(uLong crc1, uLong crc2, uLong op) {
+ return multmodp(op, crc1) ^ (crc2 & 0xffffffff);
}
generated by cgit v1.2.3 (git 2.25.1) at 2024-04-18 13:07:30 +0000