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| author | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-03-09 13:19:48 +0000 |
|---|---|---|
| committer | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-03-09 13:20:02 +0000 |
| commit | 58daab21cd043e1dc37024a7f99b396788372918 (patch) | |
| tree | 96771e43bb69f7c1c2b0b4f7374cb74d7866d0cb /web/server/h2o/libh2o/deps/mruby/src/crc.c | |
| parent | Releasing debian version 1.43.2-1. (diff) | |
| download | netdata-58daab21cd043e1dc37024a7f99b396788372918.tar.xz netdata-58daab21cd043e1dc37024a7f99b396788372918.zip | |
Merging upstream version 1.44.3.
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to '')
| -rw-r--r-- | web/server/h2o/libh2o/deps/mruby/src/crc.c | 39 |
1 files changed, 39 insertions, 0 deletions
diff --git a/web/server/h2o/libh2o/deps/mruby/src/crc.c b/web/server/h2o/libh2o/deps/mruby/src/crc.c new file mode 100644 index 000000000..290b2ca0e --- /dev/null +++ b/web/server/h2o/libh2o/deps/mruby/src/crc.c @@ -0,0 +1,39 @@ +/* +** crc.c - calculate CRC +** +** See Copyright Notice in mruby.h +*/ + +#include <limits.h> +#include <stdint.h> +#include <stddef.h> + +/* Calculate CRC (CRC-16-CCITT) +** +** 0000_0000_0000_0000_0000_0000_0000_0000 +** ^|------- CRC -------|- work --| +** carry +*/ +#define CRC_16_CCITT 0x11021ul /* x^16+x^12+x^5+1 */ +#define CRC_XOR_PATTERN (CRC_16_CCITT << 8) +#define CRC_CARRY_BIT (0x01000000) + +uint16_t +calc_crc_16_ccitt(const uint8_t *src, size_t nbytes, uint16_t crc) +{ + size_t ibyte; + uint32_t ibit; + uint32_t crcwk = crc << 8; + + for (ibyte = 0; ibyte < nbytes; ibyte++) { + crcwk |= *src++; + for (ibit = 0; ibit < CHAR_BIT; ibit++) { + crcwk <<= 1; + if (crcwk & CRC_CARRY_BIT) { + crcwk ^= CRC_XOR_PATTERN; + } + } + } + return (uint16_t)(crcwk >> 8); +} + |