diff options
Diffstat (limited to 'archival/gzip.c')
-rw-r--r-- | archival/gzip.c | 35 |
1 files changed, 10 insertions, 25 deletions
diff --git a/archival/gzip.c b/archival/gzip.c index fa6e85b66..41ed3a2c7 100644 --- a/archival/gzip.c +++ b/archival/gzip.c @@ -293,6 +293,7 @@ static int ofd; /* output file descriptor */ static unsigned insize; /* valid bytes in inbuf */ static unsigned outcnt; /* bytes in output buffer */ +static uint32_t *crc_32_tab; /* Output a 16 bit value, lsb first */ static void put_short(ush w) @@ -344,32 +345,13 @@ static void write_buf(int fd, void *buf, unsigned cnt) * pointer, then initialize the crc shift register contents instead. * Return the current crc in either case. */ -static ulg updcrc(uch * s, unsigned n) +static uint32_t updcrc(uch * s, unsigned n) { - static ulg crc = (ulg) 0xffffffffL; /* shift register contents */ - register ulg c; /* temporary variable */ - static unsigned long crc_32_tab[256]; - - if (crc_32_tab[1] == 0x00000000L) { - unsigned long csr; /* crc shift register */ - const unsigned long e = 0xedb88320L; /* polynomial exclusive-or pattern */ - int i; /* counter for all possible eight bit values */ - int k; /* byte being shifted into crc apparatus */ - - /* Compute table of CRC's. */ - for (i = 1; i < 256; i++) { - csr = i; - /* The idea to initialize the register with the byte instead of - * zero was stolen from Haruhiko Okumura's ar002 - */ - for (k = 8; k; k--) - csr = csr & 1 ? (csr >> 1) ^ e : csr >> 1; - crc_32_tab[i] = csr; - } - } + static uint32_t crc = ~0; /* shift register contents */ + uint32_t c; /* temporary variable */ if (s == NULL) { - c = 0xffffffffL; + c = ~0; } else { c = crc; if (n) @@ -378,7 +360,7 @@ static ulg updcrc(uch * s, unsigned n) } while (--n); } crc = c; - return c ^ 0xffffffffL; /* (instead of ~c for 64-bit machines) */ + return ~c; } /* bits.c -- output variable-length bit strings @@ -1223,6 +1205,9 @@ int gzip_main(int argc, char **argv) ALLOC(uch, window, 2L * WSIZE); ALLOC(ush, tab_prefix, 1L << BITS); + /* Initialise the CRC32 table */ + crc_32_tab = bb_crc32_filltable(0); + clear_bufs(); part_nb = 0; @@ -2416,7 +2401,7 @@ static void set_file_type(void) */ -static ulg crc; /* crc on uncompressed file data */ +static uint32_t crc; /* crc on uncompressed file data */ static long header_bytes; /* number of bytes in gzip header */ static void put_long(ulg n) |