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-rw-r--r--lib/libz/crc32.c153
1 files changed, 86 insertions, 67 deletions
diff --git a/lib/libz/crc32.c b/lib/libz/crc32.c
index fe88dba..35417e2 100644
--- a/lib/libz/crc32.c
+++ b/lib/libz/crc32.c
@@ -1,6 +1,6 @@
-/* $OpenBSD: crc32.c,v 1.8 2005/07/20 15:56:41 millert Exp $ */
+/* $OpenBSD: crc32.c,v 1.9 2021/07/04 14:24:49 tb Exp $ */
/* crc32.c -- compute the CRC-32 of a data stream
- * Copyright (C) 1995-2005 Mark Adler
+ * Copyright (C) 1995-2006, 2010, 2011, 2012, 2016 Mark Adler
* For conditions of distribution and use, see copyright notice in zlib.h
*
* Thanks to Rodney Brown <rbrown64@csc.com.au> for his contribution of faster
@@ -16,6 +16,8 @@
of the crc tables. Therefore, if you #define DYNAMIC_CRC_TABLE, you should
first call get_crc_table() to initialize the tables before allowing more than
one thread to use crc32().
+
+ DYNAMIC_CRC_TABLE and MAKECRCH can be #defined to write out crc32.h.
*/
#ifdef MAKECRCH
@@ -24,40 +26,18 @@
# define DYNAMIC_CRC_TABLE
# endif /* !DYNAMIC_CRC_TABLE */
#endif /* MAKECRCH */
-
-#include "zutil.h" /* for STDC and FAR definitions */
-#define local static
-
-/* Find a four-byte integer type for crc32_little() and crc32_big(). */
-#ifndef NOBYFOUR
-# ifdef STDC /* need ANSI C limits.h to determine sizes */
-# include <limits.h>
-# define BYFOUR
-# if (UINT_MAX == 0xffffffffUL)
- typedef unsigned int u4;
-# else
-# if (ULONG_MAX == 0xffffffffUL)
- typedef unsigned long u4;
-# else
-# if (USHRT_MAX == 0xffffffffUL)
- typedef unsigned short u4;
-# else
-# undef BYFOUR /* can't find a four-byte integer type! */
-# endif
-# endif
-# endif
-# endif /* STDC */
-#endif /* !NOBYFOUR */
+#include "zutil.h" /* for STDC and FAR definitions */
/* Definitions for doing the crc four data bytes at a time. */
+#if !defined(NOBYFOUR) && defined(Z_U4)
+# define BYFOUR
+#endif
#ifdef BYFOUR
-# define REV(w) (((w)>>24)+(((w)>>8)&0xff00)+ \
- (((w)&0xff00)<<8)+(((w)&0xff)<<24))
local unsigned long crc32_little OF((unsigned long,
- const unsigned char FAR *, unsigned));
+ const unsigned char FAR *, z_size_t));
local unsigned long crc32_big OF((unsigned long,
- const unsigned char FAR *, unsigned));
+ const unsigned char FAR *, z_size_t));
# define TBLS 8
#else
# define TBLS 1
@@ -67,14 +47,16 @@
local unsigned long gf2_matrix_times OF((unsigned long *mat,
unsigned long vec));
local void gf2_matrix_square OF((unsigned long *square, unsigned long *mat));
+local uLong crc32_combine_ OF((uLong crc1, uLong crc2, z_off64_t len2));
+
#ifdef DYNAMIC_CRC_TABLE
local volatile int crc_table_empty = 1;
-local unsigned long FAR crc_table[TBLS][256];
+local z_crc_t FAR crc_table[TBLS][256];
local void make_crc_table OF((void));
#ifdef MAKECRCH
- local void write_table OF((FILE *, const unsigned long FAR *));
+ local void write_table OF((FILE *, const z_crc_t FAR *));
#endif /* MAKECRCH */
/*
Generate tables for a byte-wise 32-bit CRC calculation on the polynomial:
@@ -104,9 +86,9 @@ local void make_crc_table OF((void));
*/
local void make_crc_table()
{
- unsigned long c;
+ z_crc_t c;
int n, k;
- unsigned long poly; /* polynomial exclusive-or pattern */
+ z_crc_t poly; /* polynomial exclusive-or pattern */
/* terms of polynomial defining this crc (except x^32): */
static volatile int first = 1; /* flag to limit concurrent making */
static const unsigned char p[] = {0,1,2,4,5,7,8,10,11,12,16,22,23,26};
@@ -118,13 +100,13 @@ local void make_crc_table()
first = 0;
/* make exclusive-or pattern from polynomial (0xedb88320UL) */
- poly = 0UL;
- for (n = 0; n < sizeof(p)/sizeof(unsigned char); n++)
- poly |= 1UL << (31 - p[n]);
+ poly = 0;
+ for (n = 0; n < (int)(sizeof(p)/sizeof(unsigned char)); n++)
+ poly |= (z_crc_t)1 << (31 - p[n]);
/* generate a crc for every 8-bit value */
for (n = 0; n < 256; n++) {
- c = (unsigned long)n;
+ c = (z_crc_t)n;
for (k = 0; k < 8; k++)
c = c & 1 ? poly ^ (c >> 1) : c >> 1;
crc_table[0][n] = c;
@@ -135,11 +117,11 @@ local void make_crc_table()
and then the byte reversal of those as well as the first table */
for (n = 0; n < 256; n++) {
c = crc_table[0][n];
- crc_table[4][n] = REV(c);
+ crc_table[4][n] = ZSWAP32(c);
for (k = 1; k < 4; k++) {
c = crc_table[0][c & 0xff] ^ (c >> 8);
crc_table[k][n] = c;
- crc_table[k + 4][n] = REV(c);
+ crc_table[k + 4][n] = ZSWAP32(c);
}
}
#endif /* BYFOUR */
@@ -161,7 +143,7 @@ local void make_crc_table()
if (out == NULL) return;
fprintf(out, "/* crc32.h -- tables for rapid CRC calculation\n");
fprintf(out, " * Generated automatically by crc32.c\n */\n\n");
- fprintf(out, "local const unsigned long FAR ");
+ fprintf(out, "local const z_crc_t FAR ");
fprintf(out, "crc_table[TBLS][256] =\n{\n {\n");
write_table(out, crc_table[0]);
# ifdef BYFOUR
@@ -181,12 +163,13 @@ local void make_crc_table()
#ifdef MAKECRCH
local void write_table(out, table)
FILE *out;
- const unsigned long FAR *table;
+ const z_crc_t FAR *table;
{
int n;
for (n = 0; n < 256; n++)
- fprintf(out, "%s0x%08lxUL%s", n % 5 ? "" : " ", table[n],
+ fprintf(out, "%s0x%08lxUL%s", n % 5 ? "" : " ",
+ (unsigned long)(table[n]),
n == 255 ? "\n" : (n % 5 == 4 ? ",\n" : ", "));
}
#endif /* MAKECRCH */
@@ -201,13 +184,13 @@ local void write_table(out, table)
/* =========================================================================
* This function can be used by asm versions of crc32()
*/
-const unsigned long FAR * ZEXPORT get_crc_table()
+const z_crc_t FAR * ZEXPORT get_crc_table()
{
#ifdef DYNAMIC_CRC_TABLE
if (crc_table_empty)
make_crc_table();
#endif /* DYNAMIC_CRC_TABLE */
- return (const unsigned long FAR *)crc_table;
+ return (const z_crc_t FAR *)crc_table;
}
/* ========================================================================= */
@@ -215,10 +198,10 @@ const unsigned long FAR * ZEXPORT get_crc_table()
#define DO8 DO1; DO1; DO1; DO1; DO1; DO1; DO1; DO1
/* ========================================================================= */
-unsigned long ZEXPORT crc32(crc, buf, len)
+unsigned long ZEXPORT crc32_z(crc, buf, len)
unsigned long crc;
const unsigned char FAR *buf;
- unsigned len;
+ z_size_t len;
{
if (buf == Z_NULL) return 0UL;
@@ -229,7 +212,7 @@ unsigned long ZEXPORT crc32(crc, buf, len)
#ifdef BYFOUR
if (sizeof(void *) == sizeof(ptrdiff_t)) {
- u4 endian;
+ z_crc_t endian;
endian = 1;
if (*((unsigned char *)(&endian)))
@@ -249,8 +232,29 @@ unsigned long ZEXPORT crc32(crc, buf, len)
return crc ^ 0xffffffffUL;
}
+/* ========================================================================= */
+unsigned long ZEXPORT crc32(crc, buf, len)
+ unsigned long crc;
+ const unsigned char FAR *buf;
+ uInt len;
+{
+ return crc32_z(crc, buf, len);
+}
+
#ifdef BYFOUR
+/*
+ This BYFOUR code accesses the passed unsigned char * buffer with a 32-bit
+ integer pointer type. This violates the strict aliasing rule, where a
+ compiler can assume, for optimization purposes, that two pointers to
+ fundamentally different types won't ever point to the same memory. This can
+ manifest as a problem only if one of the pointers is written to. This code
+ only reads from those pointers. So long as this code remains isolated in
+ this compilation unit, there won't be a problem. For this reason, this code
+ should not be copied and pasted into a compilation unit in which other code
+ writes to the buffer that is passed to these routines.
+ */
+
/* ========================================================================= */
#define DOLIT4 c ^= *buf4++; \
c = crc_table[3][c & 0xff] ^ crc_table[2][(c >> 8) & 0xff] ^ \
@@ -261,19 +265,19 @@ unsigned long ZEXPORT crc32(crc, buf, len)
local unsigned long crc32_little(crc, buf, len)
unsigned long crc;
const unsigned char FAR *buf;
- unsigned len;
+ z_size_t len;
{
- register u4 c;
- register const u4 FAR *buf4;
+ register z_crc_t c;
+ register const z_crc_t FAR *buf4;
- c = (u4)crc;
+ c = (z_crc_t)crc;
c = ~c;
while (len && ((ptrdiff_t)buf & 3)) {
c = crc_table[0][(c ^ *buf++) & 0xff] ^ (c >> 8);
len--;
}
- buf4 = (const u4 FAR *)(const void FAR *)buf;
+ buf4 = (const z_crc_t FAR *)(const void FAR *)buf;
while (len >= 32) {
DOLIT32;
len -= 32;
@@ -292,7 +296,7 @@ local unsigned long crc32_little(crc, buf, len)
}
/* ========================================================================= */
-#define DOBIG4 c ^= *++buf4; \
+#define DOBIG4 c ^= *buf4++; \
c = crc_table[4][c & 0xff] ^ crc_table[5][(c >> 8) & 0xff] ^ \
crc_table[6][(c >> 16) & 0xff] ^ crc_table[7][c >> 24]
#define DOBIG32 DOBIG4; DOBIG4; DOBIG4; DOBIG4; DOBIG4; DOBIG4; DOBIG4; DOBIG4
@@ -301,20 +305,19 @@ local unsigned long crc32_little(crc, buf, len)
local unsigned long crc32_big(crc, buf, len)
unsigned long crc;
const unsigned char FAR *buf;
- unsigned len;
+ z_size_t len;
{
- register u4 c;
- register const u4 FAR *buf4;
+ register z_crc_t c;
+ register const z_crc_t FAR *buf4;
- c = REV((u4)crc);
+ c = ZSWAP32((z_crc_t)crc);
c = ~c;
while (len && ((ptrdiff_t)buf & 3)) {
c = crc_table[4][(c >> 24) ^ *buf++] ^ (c << 8);
len--;
}
- buf4 = (const u4 FAR *)(const void FAR *)buf;
- buf4--;
+ buf4 = (const z_crc_t FAR *)(const void FAR *)buf;
while (len >= 32) {
DOBIG32;
len -= 32;
@@ -323,14 +326,13 @@ local unsigned long crc32_big(crc, buf, len)
DOBIG4;
len -= 4;
}
- buf4++;
buf = (const unsigned char FAR *)buf4;
if (len) do {
c = crc_table[4][(c >> 24) ^ *buf++] ^ (c << 8);
} while (--len);
c = ~c;
- return (unsigned long)(REV(c));
+ return (unsigned long)(ZSWAP32(c));
}
#endif /* BYFOUR */
@@ -366,22 +368,22 @@ local void gf2_matrix_square(square, mat)
}
/* ========================================================================= */
-uLong ZEXPORT crc32_combine(crc1, crc2, len2)
+local uLong crc32_combine_(crc1, crc2, len2)
uLong crc1;
uLong crc2;
- z_off_t len2;
+ z_off64_t len2;
{
int n;
unsigned long row;
unsigned long even[GF2_DIM]; /* even-power-of-two zeros operator */
unsigned long odd[GF2_DIM]; /* odd-power-of-two zeros operator */
- /* degenerate case */
- if (len2 == 0)
+ /* degenerate case (also disallow negative lengths) */
+ if (len2 <= 0)
return crc1;
/* put operator for one zero bit in odd */
- odd[0] = 0xedb88320L; /* CRC-32 polynomial */
+ odd[0] = 0xedb88320UL; /* CRC-32 polynomial */
row = 1;
for (n = 1; n < GF2_DIM; n++) {
odd[n] = row;
@@ -420,3 +422,20 @@ uLong ZEXPORT crc32_combine(crc1, crc2, len2)
crc1 ^= crc2;
return crc1;
}
+
+/* ========================================================================= */
+uLong ZEXPORT crc32_combine(crc1, crc2, len2)
+ uLong crc1;
+ uLong crc2;
+ z_off_t len2;
+{
+ return crc32_combine_(crc1, crc2, len2);
+}
+
+uLong ZEXPORT crc32_combine64(crc1, crc2, len2)
+ uLong crc1;
+ uLong crc2;
+ z_off64_t len2;
+{
+ return crc32_combine_(crc1, crc2, len2);
+}
generated by cgit v1.2.3 (git 2.39.1) at 2024-04-25 15:51:41 +0000