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authorMark Adler <madler@alumni.caltech.edu>2012-04-29 16:18:12 -0700
committerMark Adler <madler@alumni.caltech.edu>2012-04-29 16:18:12 -0700
commit6c9bd474aa08312ef2e2e9655a80e18db24a1680 (patch)
tree2539e04a1037206dc3853fbdbb33194bb2690aaa /crc32.c
parent1be117908397b0ce065c07c60fa2b4ae778ff112 (diff)
downloadzlib-6c9bd474aa08312ef2e2e9655a80e18db24a1680.tar.gz
Fix type mismatch between get_crc_table() and crc_table.
crc_table is made using a four-byte integer (when that can be determined). However get_crc_table() returned a pointer to an unsigned long, which could be eight bytes. This fixes that by creating a new z_crc_t type for the crc_table. This type is also used for the BYFOUR crc calculations that depend on a four-byte type. The four-byte type can now be determined by ./configure, which also solves a problem where ./configure --solo would never use BYFOUR. No the Z_U4 #define indicates that four- byte integer was found either by ./configure or by zconf.h.
Diffstat (limited to 'crc32.c')
-rw-r--r--crc32.c67
1 files changed, 22 insertions, 45 deletions
diff --git a/crc32.c b/crc32.c
index 5cfc8ff..979a719 100644
--- a/crc32.c
+++ b/crc32.c
@@ -32,40 +32,17 @@
#define local static
-/* Find a four-byte integer type for crc32_little() and crc32_big(). */
-#ifdef Z_SOLO
-# define NOBYFOUR
-#endif
-#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 */
-
/* Definitions for doing the crc four data bytes at a time. */
+#if !defined(NOBYFOUR) && defined(Z_U4)
+# define BYFOUR
+#endif
#ifdef BYFOUR
- typedef u4 crc_table_t;
local unsigned long crc32_little OF((unsigned long,
const unsigned char FAR *, unsigned));
local unsigned long crc32_big OF((unsigned long,
const unsigned char FAR *, unsigned));
# define TBLS 8
#else
- typedef unsigned long crc_table_t;
# define TBLS 1
#endif /* BYFOUR */
@@ -79,10 +56,10 @@ 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 crc_table_t 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 crc_table_t 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:
@@ -112,9 +89,9 @@ local void make_crc_table OF((void));
*/
local void make_crc_table()
{
- crc_table_t c;
+ z_crc_t c;
int n, k;
- crc_table_t 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};
@@ -128,11 +105,11 @@ local void make_crc_table()
/* make exclusive-or pattern from polynomial (0xedb88320UL) */
poly = 0;
for (n = 0; n < (int)(sizeof(p)/sizeof(unsigned char)); n++)
- poly |= (crc_table_t)1 << (31 - p[n]);
+ poly |= (z_crc_t)1 << (31 - p[n]);
/* generate a crc for every 8-bit value */
for (n = 0; n < 256; n++) {
- c = (crc_table_t)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;
@@ -169,7 +146,7 @@ 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 crc_table_t 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
@@ -189,7 +166,7 @@ local void make_crc_table()
#ifdef MAKECRCH
local void write_table(out, table)
FILE *out;
- const crc_table_t FAR *table;
+ const z_crc_t FAR *table;
{
int n;
@@ -210,13 +187,13 @@ 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;
}
/* ========================================================================= */
@@ -238,7 +215,7 @@ 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)))
@@ -272,17 +249,17 @@ local unsigned long crc32_little(crc, buf, len)
const unsigned char FAR *buf;
unsigned 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;
@@ -312,17 +289,17 @@ local unsigned long crc32_big(crc, buf, len)
const unsigned char FAR *buf;
unsigned len;
{
- register u4 c;
- register const u4 FAR *buf4;
+ register z_crc_t c;
+ register const z_crc_t FAR *buf4;
- c = ZSWAP32((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 = (const z_crc_t FAR *)(const void FAR *)buf;
buf4--;
while (len >= 32) {
DOBIG32;