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authorIsaac Dunham <idunham@lavabit.com>2013-07-06 11:26:15 -0500
committerIsaac Dunham <idunham@lavabit.com>2013-07-06 11:26:15 -0500
commitc810f9f80b9db62de09b6cf4c6ca770eed72ce53 (patch)
tree2ef2dbf640e94ecd7918b54a1e1bea7ce779f78c /toys/pending/xzcat.c
parent8e9ec867e5753e63778d67c3cb1cce68792f7b24 (diff)
downloadtoybox-c810f9f80b9db62de09b6cf4c6ca770eed72ce53.tar.gz
This inlines CRC64, and nothing more.
The functions involved were called only once.
Diffstat (limited to 'toys/pending/xzcat.c')
-rw-r--r--toys/pending/xzcat.c63
1 files changed, 21 insertions, 42 deletions
diff --git a/toys/pending/xzcat.c b/toys/pending/xzcat.c
index 5d69087c..3bbb8230 100644
--- a/toys/pending/xzcat.c
+++ b/toys/pending/xzcat.c
@@ -249,47 +249,8 @@ uint32_t xz_crc32(const uint8_t *buf, size_t size, uint32_t crc)
return ~crc;
}
-/*
- * This must be called before any other xz_* function (but after crc_init())
- * to initialize the CRC64 lookup table.
- */
static uint64_t xz_crc64_table[256];
-void xz_crc64_init(void)
-{
- const uint64_t poly = 0xC96C5795D7870F42ULL;
-
- uint32_t i;
- uint32_t j;
- uint64_t r;
-
- for (i = 0; i < 256; ++i) {
- r = i;
- for (j = 0; j < 8; ++j)
- r = (r >> 1) ^ (poly & ~((r & 1) - 1));
-
- xz_crc64_table[i] = r;
- }
-
- return;
-}
-
-/*
- * Update CRC64 value using the polynomial from ECMA-182. To start a new
- * calculation, the third argument must be zero. To continue the calculation,
- * the previously returned value is passed as the third argument.
- */
-uint64_t xz_crc64(const uint8_t *buf, size_t size, uint64_t crc)
-{
- crc = ~crc;
-
- while (size != 0) {
- crc = xz_crc64_table[*buf++ ^ (crc & 0xFF)] ^ (crc >> 8);
- --size;
- }
-
- return ~crc;
-}
// END xz.h
@@ -304,7 +265,19 @@ void xzcat_main(void)
const char *msg;
crc_init(xz_crc32_table, 1);
- xz_crc64_init();
+ const uint64_t poly = 0xC96C5795D7870F42ULL;
+ uint32_t i;
+ uint32_t j;
+ uint64_t r;
+
+ /* initialize CRC64 table*/
+ for (i = 0; i < 256; ++i) {
+ r = i;
+ for (j = 0; j < 8; ++j)
+ r = (r >> 1) ^ (poly & ~((r & 1) - 1));
+
+ xz_crc64_table[i] = r;
+ }
/*
* Support up to 64 MiB dictionary. The actually needed memory
@@ -2767,8 +2740,14 @@ static enum xz_ret dec_block(struct xz_dec *s, struct xz_buf *b)
s->crc = xz_crc32(b->out + s->out_start,
b->out_pos - s->out_start, s->crc);
else if (s->check_type == XZ_CHECK_CRC64)
- s->crc = xz_crc64(b->out + s->out_start,
- b->out_pos - s->out_start, s->crc);
+ s->crc = ~(s->crc);
+ size_t size = b->out_pos - s->out_start;
+ uint8_t *buf = b->out + s->out_start;
+ while (size) {
+ s->crc = xz_crc64_table[*buf++ ^ (s->crc & 0xFF)] ^ (s->crc >> 8);
+ --size;
+ }
+ s->crc=~(s->crc);
if (ret == XZ_STREAM_END) {
if (s->block_header.compressed != VLI_UNKNOWN