Add a slicing-by-8 CRC32c implementation for metadata checksumming.
Adapted from Bob Pearson's kernel patch.
Signed-off-by: Darrick J. Wong <djwong@xxxxxxxxxx>
---
lib/ext2fs/Makefile.in | 15 +
lib/ext2fs/crc32c.c | 435 ++++++++++++++++++++++++++++++++++++++++++
lib/ext2fs/crc32c_defs.h | 67 ++++++
lib/ext2fs/ext2fs.h | 4
lib/ext2fs/gen_crc32ctable.c | 123 ++++++++++++
5 files changed, 644 insertions(+), 0 deletions(-)
create mode 100644 lib/ext2fs/crc32c.c
create mode 100644 lib/ext2fs/crc32c_defs.h
create mode 100644 lib/ext2fs/gen_crc32ctable.c
diff --git a/lib/ext2fs/Makefile.in b/lib/ext2fs/Makefile.in
index f6338f0..f05cba8 100644
--- a/lib/ext2fs/Makefile.in
+++ b/lib/ext2fs/Makefile.in
@@ -33,6 +33,7 @@ OBJS= $(DEBUGFS_LIB_OBJS) $(RESIZE_LIB_OBJS) $(E2IMAGE_LIB_OBJS) \
check_desc.o \
closefs.o \
crc16.o \
+ crc32c.o \
csum.o \
dblist.o \
dblist_dir.o \
@@ -99,6 +100,8 @@ SRCS= ext2_err.c \
$(srcdir)/check_desc.c \
$(srcdir)/closefs.c \
$(srcdir)/crc16.c \
+ $(srcdir)/crc32c.c \
+ $(srcdir)/gen_crc32ctable.c \
$(srcdir)/csum.c \
$(srcdir)/dblist.c \
$(srcdir)/dblist_dir.c \
@@ -393,6 +396,15 @@ $(top_builddir)/lib/ext2fs/ext2_err.h: ext2_err.h
$(OBJS): subdirs
+gen_crc32ctable: $(srcdir)/gen_crc32ctable.c
+ $(E) " CC $@"
+ $(Q) $(BUILD_CC) $(BUILD_CFLAGS) -o gen_crc32ctable \
+ $(srcdir)/gen_crc32ctable.c
+
+crc32c_table.h: gen_crc32ctable
+ $(E) " GEN32CTABLE $@"
+ $(Q) ./gen_crc32ctable > crc32c_table.h
+
# +++ Dependency line eater +++
#
# Makefile dependencies follow. This must be the last section in
@@ -476,6 +488,9 @@ closefs.o: $(srcdir)/closefs.c $(srcdir)/ext2_fs.h \
$(srcdir)/bitops.h
crc16.o: $(srcdir)/crc16.c $(top_builddir)/lib/ext2fs/ext2_types.h \
$(srcdir)/crc16.h
+crc32c.o: $(srcdir)/crc32c.c $(top_builddir)/lib/ext2fs/ext2_types.h \
+ $(srcdir)/crc32c_table.h $(srcdir)/crc32c_defs.h
+gen_crc32ctable.o: $(srcdir)/gen_crc32ctable.c $(srcdir)/crc32c_defs.h
csum.o: $(srcdir)/csum.c $(srcdir)/ext2_fs.h \
$(top_builddir)/lib/ext2fs/ext2_types.h $(srcdir)/ext2fs.h \
$(srcdir)/ext2_fs.h $(srcdir)/ext3_extents.h $(top_srcdir)/lib/et/com_err.h \
diff --git a/lib/ext2fs/crc32c.c b/lib/ext2fs/crc32c.c
new file mode 100644
index 0000000..229bd37
--- /dev/null
+++ b/lib/ext2fs/crc32c.c
@@ -0,0 +1,435 @@
+/*
+ * crc32c.c
+ *
+ * August 26, 2011 Darrick J. Wong <djwong at us.ibm.com>
+ * Reuse Bob Pearson's slice-by-8 implementation for e2fsprogs.
+ *
+ * July 20, 2011 Bob Pearson <rpearson at systemfabricworks.com>
+ * added slice by 8 algorithm to the existing conventional and
+ * slice by 4 algorithms.
+ *
+ * Oct 15, 2000 Matt Domsch <Matt_Domsch@xxxxxxxx>
+ * Nicer crc32 functions/docs submitted by linux@xxxxxxxxxxx. Thanks!
+ * Code was from the public domain, copyright abandoned. Code was
+ * subsequently included in the kernel, thus was re-licensed under the
+ * GNU GPL v2.
+ *
+ * Oct 12, 2000 Matt Domsch <Matt_Domsch@xxxxxxxx>
+ * Same crc32 function was used in 5 other places in the kernel.
+ * I made one version, and deleted the others.
+ * There are various incantations of crc32(). Some use a seed of 0 or ~0.
+ * Some xor at the end with ~0. The generic crc32() function takes
+ * seed as an argument, and doesn't xor at the end. Then individual
+ * users can do whatever they need.
+ * drivers/net/smc9194.c uses seed ~0, doesn't xor with ~0.
+ * fs/jffs2 uses seed 0, doesn't xor with ~0.
+ * fs/partitions/efi.c uses seed ~0, xor's with ~0.
+ *
+ * This source code is licensed under the GNU General Public License,
+ * Version 2. See the file COPYING for more details.
+ */
+#include <stdint.h>
+#include <endian.h>
+#include <stdlib.h>
+#define __force
+#define min(x, y) ((x) > (y) ? (y) : (x))
+#define __ALIGN_KERNEL_MASK(x, mask) (((x) + (mask)) & ~(mask))
+#define __ALIGN_KERNEL(x, a) __ALIGN_KERNEL_MASK(x, (typeof(x))(a) - 1)
+#define ALIGN(x, a) __ALIGN_KERNEL((x), (a))
+#define PTR_ALIGN(p, a) ((typeof(p))ALIGN((unsigned long)(p), (a)))
+#include "crc32c_defs.h"
+
+#if CRC_LE_BITS > 8
+# define tole(x) (__force uint32_t) __constant_cpu_to_le32(x)
+#else
+# define tole(x) (x)
+#endif
+
+#if CRC_BE_BITS > 8
+# define tobe(x) (__force uint32_t) __constant_cpu_to_be32(x)
+#else
+# define tobe(x) (x)
+#endif
+
+#include "crc32c_table.h"
+
+#if CRC_LE_BITS == 32
+/* slice by 4 algorithm */
+static uint32_t crc32c_le_body(uint32_t crc, uint8_t const *buf, size_t len)
+{
+ const uint8_t *p8;
+ const uint32_t *p32;
+ size_t init_bytes;
+ size_t words;
+ size_t end_bytes;
+ size_t i;
+ uint32_t q;
+ uint8_t i0, i1, i2, i3;
+
+ crc = (__force uint32_t) __cpu_to_le32(crc);
+
+ /* unroll loop into 'init_bytes' odd bytes followed by
+ * 'words' aligned 4 byte words followed by
+ * 'end_bytes' odd bytes at the end */
+ p8 = buf;
+ p32 = (uint32_t *)PTR_ALIGN(p8, 4);
+ init_bytes = min((uintptr_t)p32 - (uintptr_t)p8, len);
+ words = (len - init_bytes) >> 2;
+ end_bytes = (len - init_bytes) & 3;
+
+ for (i = 0; i < init_bytes; i++) {
+#ifndef WORDS_BIGENDIAN
+ i0 = *p8++ ^ crc;
+ crc = t0_le[i0] ^ (crc >> 8);
+#else
+ i0 = *p8++ ^ (crc >> 24);
+ crc = t0_le[i0] ^ (crc << 8);
+#endif
+ }
+
+ /* using pre-increment below slightly faster */
+ p32--;
+
+ for (i = 0; i < words; i++) {
+#ifndef WORDS_BIGENDIAN
+ q = *++p32 ^ crc;
+ i3 = q;
+ i2 = q >> 8;
+ i1 = q >> 16;
+ i0 = q >> 24;
+ crc = t3_le[i3] ^ t2_le[i2] ^ t1_le[i1] ^ t0_le[i0];
+#else
+ q = *++p32 ^ crc;
+ i3 = q >> 24;
+ i2 = q >> 16;
+ i1 = q >> 8;
+ i0 = q;
+ crc = t3_le[i3] ^ t2_le[i2] ^ t1_le[i1] ^ t0_le[i0];
+#endif
+ }
+
+ p8 = (uint8_t *)(++p32);
+
+ for (i = 0; i < end_bytes; i++) {
+#ifndef WORDS_BIGENDIAN
+ i0 = *p8++ ^ crc;
+ crc = t0_le[i0] ^ (crc >> 8);
+#else
+ i0 = *p8++ ^ (crc >> 24);
+ crc = t0_le[i0] ^ (crc << 8);
+#endif
+ }
+
+ return __le32_to_cpu((__force __le32)crc);
+}
+#endif
+
+#if CRC_BE_BITS == 32
+static uint32_t crc32c_be_body(uint32_t crc, uint8_t const *buf, size_t len)
+{
+ const uint8_t *p8;
+ const uint32_t *p32;
+ size_t init_bytes;
+ size_t words;
+ size_t end_bytes;
+ size_t i;
+ uint32_t q;
+ uint8_t i0, i1, i2, i3;
+
+ crc = (__force uint32_t) __cpu_to_be32(crc);
+
+ p8 = buf;
+ p32 = (uint32_t *)PTR_ALIGN(p8, 4);
+ init_bytes = min((uintptr_t)p32 - (uintptr_t)p8, len);
+ words = (len - init_bytes) >> 2;
+ end_bytes = (len - init_bytes) & 3;
+
+ for (i = 0; i < init_bytes; i++) {
+#ifndef WORDS_BIGENDIAN
+ i0 = *p8++ ^ crc;
+ crc = t0_be[i0] ^ (crc >> 8);
+#else
+ i0 = *p8++ ^ (crc >> 24);
+ crc = t0_be[i0] ^ (crc << 8);
+#endif
+ }
+
+ p32--;
+
+ for (i = 0; i < words; i++) {
+#ifndef WORDS_BIGENDIAN
+ q = *++p32 ^ crc;
+ i3 = q;
+ i2 = q >> 8;
+ i1 = q >> 16;
+ i0 = q >> 24;
+ crc = t3_be[i3] ^ t2_be[i2] ^ t1_be[i1] ^ t0_be[i0];
+#else
+ q = *++p32 ^ crc;
+ i3 = q >> 24;
+ i2 = q >> 16;
+ i1 = q >> 8;
+ i0 = q;
+ crc = t3_be[i3] ^ t2_be[i2] ^ t1_be[i1] ^ t0_be[i0];
+#endif
+ }
+
+ p8 = (uint8_t *)(++p32);
+
+ for (i = 0; i < end_bytes; i++) {
+#ifndef WORDS_BIGENDIAN
+ i0 = *p8++ ^ crc;
+ crc = t0_be[i0] ^ (crc >> 8);
+#else
+ i0 = *p8++ ^ (crc >> 24);
+ crc = t0_be[i0] ^ (crc << 8);
+#endif
+ }
+
+ return __be32_to_cpu((__force __be32)crc);
+}
+#endif
+
+#if CRC_LE_BITS == 64
+/* slice by 8 algorithm */
+static uint32_t crc32c_le_body(uint32_t crc, uint8_t const *buf, size_t len)
+{
+ const uint8_t *p8;
+ const uint32_t *p32;
+ size_t init_bytes;
+ size_t words;
+ size_t end_bytes;
+ size_t i;
+ uint32_t q;
+ uint8_t i0, i1, i2, i3;
+
+ crc = (__force uint32_t) __cpu_to_le32(crc);
+
+ p8 = buf;
+ p32 = (uint32_t *)PTR_ALIGN(p8, 8);
+ init_bytes = min((uintptr_t)p32 - (uintptr_t)p8, len);
+ words = (len - init_bytes) >> 3;
+ end_bytes = (len - init_bytes) & 7;
+
+ for (i = 0; i < init_bytes; i++) {
+#ifndef WORDS_BIGENDIAN
+ i0 = *p8++ ^ crc;
+ crc = t0_le[i0] ^ (crc >> 8);
+#else
+ i0 = *p8++ ^ (crc >> 24);
+ crc = t0_le[i0] ^ (crc << 8);
+#endif
+ }
+
+ p32--;
+
+ for (i = 0; i < words; i++) {
+#ifndef WORDS_BIGENDIAN
+ q = *++p32 ^ crc;
+ i3 = q;
+ i2 = q >> 8;
+ i1 = q >> 16;
+ i0 = q >> 24;
+ crc = t7_le[i3] ^ t6_le[i2] ^ t5_le[i1] ^ t4_le[i0];
+
+ q = *++p32;
+ i3 = q;
+ i2 = q >> 8;
+ i1 = q >> 16;
+ i0 = q >> 24;
+ crc ^= t3_le[i3] ^ t2_le[i2] ^ t1_le[i1] ^ t0_le[i0];
+#else
+ q = *++p32 ^ crc;
+ i3 = q >> 24;
+ i2 = q >> 16;
+ i1 = q >> 8;
+ i0 = q;
+ crc = t7_le[i3] ^ t6_le[i2] ^ t5_le[i1] ^ t4_le[i0];
+
+ q = *++p32;
+ i3 = q >> 24;
+ i2 = q >> 16;
+ i1 = q >> 8;
+ i0 = q;
+ crc ^= t3_le[i3] ^ t2_le[i2] ^ t1_le[i1] ^ t0_le[i0];
+#endif
+ }
+
+ p8 = (uint8_t *)(++p32);
+
+ for (i = 0; i < end_bytes; i++) {
+#ifndef WORDS_BIGENDIAN
+ i0 = *p8++ ^ crc;
+ crc = t0_le[i0] ^ (crc >> 8);
+#else
+ i0 = *p8++ ^ (crc >> 24);
+ crc = t0_le[i0] ^ (crc << 8);
+#endif
+ }
+
+ return __le32_to_cpu(crc);
+}
+#endif
+
+#if CRC_BE_BITS == 64
+static uint32_t crc32c_be_body(uint32_t crc, uint8_t const *buf, size_t len)
+{
+ const uint8_t *p8;
+ const uint32_t *p32;
+ size_t init_bytes;
+ size_t words;
+ size_t end_bytes;
+ size_t i;
+ uint32_t q;
+ uint8_t i0, i1, i2, i3;
+
+ crc = (__force uint32_t) __cpu_to_be32(crc);
+
+ p8 = buf;
+ p32 = (uint32_t *)PTR_ALIGN(p8, 8);
+ init_bytes = min((uintptr_t)p32 - (uintptr_t)p8, len);
+ words = (len - init_bytes) >> 3;
+ end_bytes = (len - init_bytes) & 7;
+
+ for (i = 0; i < init_bytes; i++) {
+#ifndef WORDS_BIGENDIAN
+ i0 = *p8++ ^ crc;
+ crc = t0_be[i0] ^ (crc >> 8);
+#else
+ i0 = *p8++ ^ (crc >> 24);
+ crc = t0_be[i0] ^ (crc << 8);
+#endif
+ }
+
+ p32--;
+
+ for (i = 0; i < words; i++) {
+#ifndef WORDS_BIGENDIAN
+ q = *++p32 ^ crc;
+ i3 = q;
+ i2 = q >> 8;
+ i1 = q >> 16;
+ i0 = q >> 24;
+ crc = t7_be[i3] ^ t6_be[i2] ^ t5_be[i1] ^ t4_be[i0];
+
+ q = *++p32;
+ i3 = q;
+ i2 = q >> 8;
+ i1 = q >> 16;
+ i0 = q >> 24;
+ crc ^= t3_be[i3] ^ t2_be[i2] ^ t1_be[i1] ^ t0_be[i0];
+#else
+ q = *++p32 ^ crc;
+ i3 = q >> 24;
+ i2 = q >> 16;
+ i1 = q >> 8;
+ i0 = q;
+ crc = t7_be[i3] ^ t6_be[i2] ^ t5_be[i1] ^ t4_be[i0];
+
+ q = *++p32;
+ i3 = q >> 24;
+ i2 = q >> 16;
+ i1 = q >> 8;
+ i0 = q;
+ crc ^= t3_be[i3] ^ t2_be[i2] ^ t1_be[i1] ^ t0_be[i0];
+#endif
+ }
+
+ p8 = (uint8_t *)(++p32);
+
+ for (i = 0; i < end_bytes; i++) {
+#ifndef WORDS_BIGENDIAN
+ i0 = *p8++ ^ crc;
+ crc = t0_be[i0] ^ (crc >> 8);
+#else
+ i0 = *p8++ ^ (crc >> 24);
+ crc = t0_be[i0] ^ (crc << 8);
+#endif
+ }
+
+ return __be32_to_cpu(crc);
+}
+#endif
+
+/**
+ * crc32c_le() - Calculate bitwise little-endian CRC32c.
+ * @crc: seed value for computation. ~0 for ext4, sometimes 0 for
+ * other uses, or the previous crc32c value if computing incrementally.
+ * @p: pointer to buffer over which CRC is run
+ * @len: length of buffer @p
+ */
+uint32_t crc32c_le(uint32_t crc, unsigned char const *p, size_t len)
+{
+#if CRC_LE_BITS == 1
+ int i;
+ while (len--) {
+ crc ^= *p++;
+ for (i = 0; i < 8; i++)
+ crc = (crc >> 1) ^ ((crc & 1) ? CRCPOLY_LE : 0);
+ }
+# elif CRC_LE_BITS == 2
+ while (len--) {
+ crc ^= *p++;
+ crc = (crc >> 2) ^ t0_le[crc & 0x03];
+ crc = (crc >> 2) ^ t0_le[crc & 0x03];
+ crc = (crc >> 2) ^ t0_le[crc & 0x03];
+ crc = (crc >> 2) ^ t0_le[crc & 0x03];
+ }
+# elif CRC_LE_BITS == 4
+ while (len--) {
+ crc ^= *p++;
+ crc = (crc >> 4) ^ t0_le[crc & 0x0f];
+ crc = (crc >> 4) ^ t0_le[crc & 0x0f];
+ }
+# elif CRC_LE_BITS == 8
+ while (len--) {
+ crc ^= *p++;
+ crc = (crc >> 8) ^ t0_le[crc & 0xff];
+ }
+# else
+ crc = crc32c_le_body(crc, p, len);
+# endif
+ return crc;
+}
+
+/**
+ * crc32c_be() - Calculate bitwise big-endian CRC32c.
+ * @crc: seed value for computation. ~0 for ext4, sometimes 0 for
+ * other uses, or the previous crc32c value if computing incrementally.
+ * @p: pointer to buffer over which CRC is run
+ * @len: length of buffer @p
+ */
+uint32_t crc32c_be(uint32_t crc, unsigned char const *p, size_t len)
+{
+#if CRC_BE_BITS == 1
+ int i;
+ while (len--) {
+ crc ^= *p++ << 24;
+ for (i = 0; i < 8; i++)
+ crc = (crc << 1) ^
+ ((crc & 0x80000000) ? CRCPOLY_BE : 0);
+ }
+# elif CRC_BE_BITS == 2
+ while (len--) {
+ crc ^= *p++ << 24;
+ crc = (crc << 2) ^ t0_be[crc >> 30];
+ crc = (crc << 2) ^ t0_be[crc >> 30];
+ crc = (crc << 2) ^ t0_be[crc >> 30];
+ crc = (crc << 2) ^ t0_be[crc >> 30];
+ }
+# elif CRC_BE_BITS == 4
+ while (len--) {
+ crc ^= *p++ << 24;
+ crc = (crc << 4) ^ t0_be[crc >> 28];
+ crc = (crc << 4) ^ t0_be[crc >> 28];
+ }
+# elif CRC_BE_BITS == 8
+ while (len--) {
+ crc ^= *p++ << 24;
+ crc = (crc << 8) ^ t0_be[crc >> 24];
+ }
+# else
+ crc = crc32c_be_body(crc, p, len);
+# endif
+ return crc;
+}
diff --git a/lib/ext2fs/crc32c_defs.h b/lib/ext2fs/crc32c_defs.h
new file mode 100644
index 0000000..1752970
--- /dev/null
+++ b/lib/ext2fs/crc32c_defs.h
@@ -0,0 +1,67 @@
+/*
+ * This is the CRC32c polynomial, as outlined by Castagnoli.
+ * x^32+x^28+x^27+x^26+x^25+x^23+x^22+x^20+x^19+x^18+x^14+x^13+x^11+x^10+x^9+
+ * x^8+x^6+x^0
+ */
+#define CRCPOLY_LE 0x82F63B78
+#define CRCPOLY_BE 0x1EDC6F41
+
+/* How many bits at a time to use. Valid values are 1, 2, 4, 8, 32 and 64. */
+/* For less performance-sensitive, use 4 */
+#ifndef CRC_LE_BITS
+# define CRC_LE_BITS 64
+#endif
+#ifndef CRC_BE_BITS
+# define CRC_BE_BITS 64
+#endif
+
+/*
+ * Little-endian CRC computation. Used with serial bit streams sent
+ * lsbit-first. Be sure to use cpu_to_le32() to append the computed CRC.
+ */
+#if CRC_LE_BITS > 64 || CRC_LE_BITS < 1 || CRC_LE_BITS == 16 || \
+ CRC_LE_BITS & CRC_LE_BITS-1
+# error "CRC_LE_BITS must be one of {1, 2, 4, 8, 32, 64}"
+#endif
+
+/*
+ * Big-endian CRC computation. Used with serial bit streams sent
+ * msbit-first. Be sure to use cpu_to_be32() to append the computed CRC.
+ */
+#if CRC_BE_BITS > 64 || CRC_BE_BITS < 1 || CRC_BE_BITS == 16 || \
+ CRC_BE_BITS & CRC_BE_BITS-1
+# error "CRC_BE_BITS must be one of {1, 2, 4, 8, 32, 64}"
+#endif
+
+
+#define ___constant_swab32(x) \
+ ((uint32_t)( \
+ (((uint32_t)(x) & (uint32_t)0x000000ffUL) << 24) | \
+ (((uint32_t)(x) & (uint32_t)0x0000ff00UL) << 8) | \
+ (((uint32_t)(x) & (uint32_t)0x00ff0000UL) >> 8) | \
+ (((uint32_t)(x) & (uint32_t)0xff000000UL) >> 24)))
+
+
+#ifdef WORDS_BIGENDIAN
+#define __constant_cpu_to_le32(x) ___constant_swab32((x))
+#define __constant_cpu_to_be32(x) (x)
+#define __be32_to_cpu(x) (x)
+#define __cpu_to_be32(x) (x)
+#define __cpu_to_le32(x) (htole32((x)))
+#define __le32_to_cpu(x) (le32toh((x)))
+#else
+#define __constant_cpu_to_le32(x) (x)
+#define __constant_cpu_to_be32(x) ___constant_swab32((x))
+#define __be32_to_cpu(x) (be32toh((x)))
+#define __cpu_to_be32(x) (htobe32((x)))
+#define __cpu_to_le32(x) (x)
+#define __le32_to_cpu(x) (x)
+#endif
+
+#if (__GNUC__ >= 3)
+#define likely(x) __builtin_expect(!!(x), 1)
+#define unlikely(x) __builtin_expect(!!(x), 0)
+#else
+#define likely(x) (x)
+#define unlikely(x) (x)
+#endif
diff --git a/lib/ext2fs/ext2fs.h b/lib/ext2fs/ext2fs.h
index e638169..e571508 100644
--- a/lib/ext2fs/ext2fs.h
+++ b/lib/ext2fs/ext2fs.h
@@ -887,6 +887,10 @@ extern int ext2fs_super_and_bgd_loc(ext2_filsys fs,
int *ret_meta_bg);
extern void ext2fs_update_dynamic_rev(ext2_filsys fs);
+/* crc32c.c */
+extern __u32 crc32c_be(__u32 crc, unsigned char const *p, size_t len);
+extern __u32 crc32c_le(__u32 crc, unsigned char const *p, size_t len);
+
/* csum.c */
extern void ext2fs_group_desc_csum_set(ext2_filsys fs, dgrp_t group);
extern int ext2fs_group_desc_csum_verify(ext2_filsys fs, dgrp_t group);
diff --git a/lib/ext2fs/gen_crc32ctable.c b/lib/ext2fs/gen_crc32ctable.c
new file mode 100644
index 0000000..9996e9d
--- /dev/null
+++ b/lib/ext2fs/gen_crc32ctable.c
@@ -0,0 +1,123 @@
+#include <stdio.h>
+#include "crc32c_defs.h"
+#include <inttypes.h>
+
+#define ENTRIES_PER_LINE 4
+
+#if CRC_LE_BITS <= 8
+#define LE_TABLE_SIZE (1 << CRC_LE_BITS)
+#else
+#define LE_TABLE_SIZE 256
+#endif
+
+#if CRC_BE_BITS <= 8
+#define BE_TABLE_SIZE (1 << CRC_BE_BITS)
+#else
+#define BE_TABLE_SIZE 256
+#endif
+
+static uint32_t crc32ctable_le[8][256];
+static uint32_t crc32ctable_be[8][256];
+
+/**
+ * crc32cinit_le() - allocate and initialize LE table data
+ *
+ * crc is the crc of the byte i; other entries are filled in based on the
+ * fact that crctable[i^j] = crctable[i] ^ crctable[j].
+ *
+ */
+static void crc32cinit_le(void)
+{
+ unsigned i, j;
+ uint32_t crc = 1;
+
+ crc32ctable_le[0][0] = 0;
+
+ for (i = LE_TABLE_SIZE >> 1; i; i >>= 1) {
+ crc = (crc >> 1) ^ ((crc & 1) ? CRCPOLY_LE : 0);
+ for (j = 0; j < LE_TABLE_SIZE; j += 2 * i)
+ crc32ctable_le[0][i + j] = crc ^ crc32ctable_le[0][j];
+ }
+ for (i = 0; i < LE_TABLE_SIZE; i++) {
+ crc = crc32ctable_le[0][i];
+ for (j = 1; j < 8; j++) {
+ crc = crc32ctable_le[0][crc & 0xff] ^ (crc >> 8);
+ crc32ctable_le[j][i] = crc;
+ }
+ }
+}
+
+/**
+ * crc32cinit_be() - allocate and initialize BE table data
+ */
+static void crc32cinit_be(void)
+{
+ unsigned i, j;
+ uint32_t crc = 0x80000000;
+
+ crc32ctable_be[0][0] = 0;
+
+ for (i = 1; i < BE_TABLE_SIZE; i <<= 1) {
+ crc = (crc << 1) ^ ((crc & 0x80000000) ? CRCPOLY_BE : 0);
+ for (j = 0; j < i; j++)
+ crc32ctable_be[0][i + j] = crc ^ crc32ctable_be[0][j];
+ }
+ for (i = 0; i < BE_TABLE_SIZE; i++) {
+ crc = crc32ctable_be[0][i];
+ for (j = 1; j < 8; j++) {
+ crc = crc32ctable_be[0][(crc >> 24) & 0xff] ^
+ (crc << 8);
+ crc32ctable_be[j][i] = crc;
+ }
+ }
+}
+
+static void output_table(uint32_t table[8][256], int len, char trans)
+{
+ int i, j;
+
+ for (j = 0 ; j < 8; j++) {
+ printf("static const uint32_t t%d_%ce[] = {", j, trans);
+ for (i = 0; i < len - 1; i++) {
+ if ((i % ENTRIES_PER_LINE) == 0)
+ printf("\n");
+ printf("to%ce(0x%8.8xL),", trans, table[j][i]);
+ if ((i % ENTRIES_PER_LINE) != (ENTRIES_PER_LINE - 1))
+ printf(" ");
+ }
+ printf("to%ce(0x%8.8xL)};\n\n", trans, table[j][len - 1]);
+
+ if (trans == 'l') {
+ if ((j+1)*8 >= CRC_LE_BITS)
+ break;
+ } else {
+ if ((j+1)*8 >= CRC_BE_BITS)
+ break;
+ }
+ }
+}
+
+int main(int argc, char **argv)
+{
+ printf("/*\n");
+ printf(" * crc32ctable.h - CRC32c tables\n");
+ printf(" * this file is generated - do not edit\n");
+ printf(" * # gen_crc32ctable > crc32c_table.h\n");
+ printf(" * with\n");
+ printf(" * CRC_LE_BITS = %d\n", CRC_LE_BITS);
+ printf(" * CRC_BE_BITS = %d\n", CRC_BE_BITS);
+ printf(" */\n");
+ printf("#include <stdint.h>\n");
+
+ if (CRC_LE_BITS > 1) {
+ crc32cinit_le();
+ output_table(crc32ctable_le, LE_TABLE_SIZE, 'l');
+ }
+
+ if (CRC_BE_BITS > 1) {
+ crc32cinit_be();
+ output_table(crc32ctable_be, BE_TABLE_SIZE, 'b');
+ }
+
+ return 0;
+}
--
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