libbb: introduce and use common crc32 routine

function                                             old     new   delta
crc32_block_endian1                                    -      37     +37
crc32_block_endian0                                    -      34     +34
global_crc32_table                                     -       8      +8
file_read                                             82      87      +5
gzip_main                                            211     214      +3
xz_crc32                                              40      35      -5
crc32_table                                            8       -      -8
calculate_gunzip_crc                                  54      34     -20
lzo_crc32                                             54      25     -29
cksum_main                                           298     211     -87
------------------------------------------------------------------------------
(add/remove: 3/1 grow/shrink: 2/4 up/down: 87/-149)           Total: -62 bytes

Signed-off-by: Denys Vlasenko <dvlasenk@redhat.com>
This commit is contained in:
Denys Vlasenko 2010-10-27 15:26:45 +02:00
parent dd88ba88f5
commit 9ce642f974
9 changed files with 49 additions and 73 deletions

View File

@ -340,7 +340,7 @@ struct globals {
ulg bits_sent; /* bit length of the compressed data */
#endif
uint32_t *crc_32_tab;
/*uint32_t *crc_32_tab;*/
uint32_t crc; /* shift register contents */
};
@ -393,15 +393,9 @@ static void put_32bit(ulg n)
* pointer, then initialize the crc shift register contents instead.
* Return the current crc in either case.
*/
static uint32_t updcrc(uch * s, unsigned n)
static void updcrc(uch * s, unsigned n)
{
uint32_t c = G1.crc;
while (n) {
c = G1.crc_32_tab[(uch)(c ^ *s++)] ^ (c >> 8);
n--;
}
G1.crc = c;
return c;
G1.crc = crc32_block_endian0(G1.crc, s, n, global_crc32_table /*G1.crc_32_tab*/);
}
@ -2104,8 +2098,8 @@ int gzip_main(int argc UNUSED_PARAM, char **argv)
ALLOC(uch, G1.window, 2L * WSIZE);
ALLOC(ush, G1.prev, 1L << BITS);
/* Initialise the CRC32 table */
G1.crc_32_tab = crc32_filltable(NULL, 0);
/* Initialize the CRC32 table */
global_crc32_table = crc32_filltable(NULL, 0);
return bbunpack(argv, pack_gzip, append_ext, "gz");
}

View File

@ -22,17 +22,9 @@
/* We use our own crc32 function */
#define XZ_INTERNAL_CRC32 0
static uint32_t *crc32_table;
static uint32_t xz_crc32(const uint8_t *buf, size_t size, uint32_t crc)
{
crc = ~crc;
while (size != 0) {
crc = crc32_table[*buf++ ^ (crc & 0xFF)] ^ (crc >> 8);
--size;
}
return ~crc;
return ~crc32_block_endian0(~crc, buf, size, global_crc32_table);
}
/* We use arch-optimized unaligned accessors */
@ -53,8 +45,8 @@ unpack_xz_stream(int src_fd, int dst_fd)
unsigned char *membuf;
IF_DESKTOP(long long) int total = 0;
if (!crc32_table)
crc32_table = crc32_filltable(NULL, /*endian:*/ 0);
if (!global_crc32_table)
global_crc32_table = crc32_filltable(NULL, /*endian:*/ 0);
memset(&iobuf, 0, sizeof(iobuf));
/* Preload XZ file signature */

View File

@ -925,10 +925,7 @@ static int inflate_block(STATE_PARAM smallint *e)
/* Two callsites, both in inflate_get_next_window */
static void calculate_gunzip_crc(STATE_PARAM_ONLY)
{
unsigned n;
for (n = 0; n < gunzip_outbuf_count; n++) {
gunzip_crc = gunzip_crc_table[((int) gunzip_crc ^ (gunzip_window[n])) & 0xff] ^ (gunzip_crc >> 8);
}
gunzip_crc = crc32_block_endian0(gunzip_crc, gunzip_window, gunzip_outbuf_count, gunzip_crc_table);
gunzip_bytes_out += gunzip_outbuf_count;
}

View File

@ -393,7 +393,7 @@ typedef struct header_t {
} header_t;
struct globals {
const uint32_t *lzo_crc32_table;
/*const uint32_t *lzo_crc32_table;*/
chksum_t chksum_in;
chksum_t chksum_out;
} FIX_ALIASING;
@ -468,19 +468,10 @@ lzo_adler32(uint32_t adler, const uint8_t* buf, unsigned len)
static FAST_FUNC uint32_t
lzo_crc32(uint32_t c, const uint8_t* buf, unsigned len)
{
uint32_t crc;
//if (buf == NULL) - impossible
// return 0;
if (buf == NULL)
return 0;
crc = ~c;
if (len != 0) do {
crc = G.lzo_crc32_table[(uint8_t)((int)crc ^ *buf)] ^ (crc >> 8);
buf += 1;
len -= 1;
} while (len > 0);
return ~crc;
return ~crc32_block_endian0(~c, buf, len, global_crc32_table);
}
/**********************************************************************/
@ -679,8 +670,7 @@ static NOINLINE smallint lzo_compress(const header_t *h)
if (dst_len < src_len) {
/* write checksum of compressed block */
if (h->flags & F_ADLER32_C)
write32(lzo_adler32(ADLER32_INIT_VALUE, b2,
dst_len));
write32(lzo_adler32(ADLER32_INIT_VALUE, b2, dst_len));
if (h->flags & F_CRC32_C)
write32(lzo_crc32(CRC32_INIT_VALUE, b2, dst_len));
/* write compressed block data */
@ -1080,6 +1070,6 @@ int lzop_main(int argc UNUSED_PARAM, char **argv)
if (applet_name[0] == 'u')
option_mask32 |= OPT_DECOMPRESS;
G.lzo_crc32_table = crc32_filltable(NULL, 0);
global_crc32_table = crc32_filltable(NULL, 0);
return bbunpack(argv, pack_lzop, make_new_name_lzop, /*unused:*/ NULL);
}

View File

@ -18,7 +18,6 @@ int cksum_main(int argc UNUSED_PARAM, char **argv)
off_t length, filesize;
int bytes_read;
int exit_code = EXIT_SUCCESS;
uint8_t *cp;
#if ENABLE_DESKTOP
getopt32(argv, ""); /* coreutils 6.9 compat */
@ -39,11 +38,7 @@ int cksum_main(int argc UNUSED_PARAM, char **argv)
#define read_buf bb_common_bufsiz1
while ((bytes_read = safe_read(fd, read_buf, sizeof(read_buf))) > 0) {
cp = (uint8_t *) read_buf;
length += bytes_read;
do {
crc = (crc << 8) ^ crc32_table[(crc >> 24) ^ *cp++];
} while (--bytes_read);
crc = crc32_block_endian1(crc, read_buf, bytes_read, crc32_table);
}
close(fd);

View File

@ -1543,11 +1543,10 @@ void sha512_begin(sha512_ctx_t *ctx) FAST_FUNC;
void sha512_hash(sha512_ctx_t *ctx, const void *buffer, size_t len) FAST_FUNC;
void sha512_end(sha512_ctx_t *ctx, void *resbuf) FAST_FUNC;
/* TODO: add global crc32_table pointer and create
* LE and BE functions to calculate crc32 over given bytes.
* Currently we have about five reimplementations...
*/
extern uint32_t *global_crc32_table;
uint32_t *crc32_filltable(uint32_t *tbl256, int endian) FAST_FUNC;
uint32_t crc32_block_endian1(uint32_t val, const void *buf, unsigned len, uint32_t *crc_table) FAST_FUNC;
uint32_t crc32_block_endian0(uint32_t val, const void *buf, unsigned len, uint32_t *crc_table) FAST_FUNC;
typedef struct masks_labels_t {
const char *labels;

View File

@ -18,6 +18,8 @@
#include "libbb.h"
uint32_t *global_crc32_table;
uint32_t* FAST_FUNC crc32_filltable(uint32_t *crc_table, int endian)
{
uint32_t polynomial = endian ? 0x04c11db7 : 0xedb88320;
@ -40,3 +42,25 @@ uint32_t* FAST_FUNC crc32_filltable(uint32_t *crc_table, int endian)
return crc_table - 256;
}
uint32_t FAST_FUNC crc32_block_endian1(uint32_t val, const void *buf, unsigned len, uint32_t *crc_table)
{
const void *end = (uint8_t*)buf + len;
while (buf != end) {
val = (val << 8) ^ crc_table[(val >> 24) ^ *(uint8_t*)buf];
buf = (uint8_t*)buf + 1;
}
return val;
}
uint32_t FAST_FUNC crc32_block_endian0(uint32_t val, const void *buf, unsigned len, uint32_t *crc_table)
{
const void *end = (uint8_t*)buf + len;
while (buf != end) {
val = crc_table [(uint8_t)val ^ *(uint8_t*)buf] ^ (val >> 8);
buf = (uint8_t*)buf + 1;
}
return val;
}

View File

@ -42,15 +42,6 @@ but mtd/jffs2-user.h is gone now (at least 2.6.31.6 does not have it anymore)
#define cpu_to_je16(v) ((jint16_t){(v)})
#define cpu_to_je32(v) ((jint32_t){(v)})
static uint32_t crc32(uint32_t val, const void *ss, int len,
uint32_t *crc32_table)
{
const unsigned char *s = ss;
while (--len >= 0)
val = crc32_table[(val ^ *s++) & 0xff] ^ (val >> 8);
return val;
}
static void show_progress(mtd_info_t *meminfo, erase_info_t *erase)
{
printf("\rErasing %u Kibyte @ %x - %2u%% complete.",
@ -131,8 +122,9 @@ int flash_eraseall_main(int argc UNUSED_PARAM, char **argv)
cleanmarker.totlen = cpu_to_je32(8);
}
cleanmarker.hdr_crc = cpu_to_je32(crc32(0, &cleanmarker, sizeof(struct jffs2_unknown_node) - 4,
crc32_table));
cleanmarker.hdr_crc = cpu_to_je32(
crc32_block_endian0(0, &cleanmarker, sizeof(struct jffs2_unknown_node) - 4, crc32_table)
);
}
/* Don't want to destroy progress indicator by bb_error_msg's */

View File

@ -46,8 +46,6 @@ static unsigned int n_parts;
static unsigned int part_array_len;
static unsigned int part_entry_len;
static uint32_t *crc32_table;
static inline gpt_partition *
gpt_part(int i)
{
@ -61,12 +59,7 @@ gpt_part(int i)
static uint32_t
gpt_crc32(void *buf, int len)
{
uint32_t crc = 0xffffffff;
for (; len > 0; len--, buf++) {
crc = crc32_table[(crc ^ *((char *)buf)) & 0xff] ^ (crc >> 8);
}
return crc ^ 0xffffffff;
return 0xffffffff ^ crc32_block_endian0(0xffffffff, buf, len, global_crc32_table);
}
static void
@ -160,8 +153,8 @@ check_gpt_label(void)
return 0;
}
if (!crc32_table) {
crc32_table = crc32_filltable(NULL, 0);
if (!global_crc32_table) {
global_crc32_table = crc32_filltable(NULL, 0);
}
crc = SWAP_LE32(gpt_hdr->hdr_crc32);