hanzhijian
87d84e437a
Add crc32_ieee() and crc32_ieeepart() that produce CRC32 values
compatible with Linux/zlib. The difference from the existing crc32():
crc32(): init=0, no final XOR (NuttX native)
crc32_ieee(): init=0xFFFFFFFF, final XOR 0xFFFFFFFF (Linux/zlib)
The existing crc32() and crc32part() are unchanged to avoid breaking
existing callers (bbsram, sbram, etc.).
New functions:
crc32_ieee(src, len) - full CRC, Linux-compatible
crc32_ieeepart(src, len, crcval) - incremental CRC, Linux-compatible
Verified on sim:nsh against known Linux zlib test vectors:
crc32_ieee("hello") = 0x3610a686 (Linux: 0x3610a686) PASS
crc32_ieee("123456789") = 0xcbf43926 (Linux: 0xcbf43926) PASS
crc32_ieee("") = 0x00000000 (Linux: 0x00000000) PASS
crc32_ieeepart incremental = 0xcbf43926 PASS
crc32("hello") = 0xf032519b (unchanged) PASS
Signed-off-by: hanzhijian <hanzhijian@zepp.com>
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