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Explicit implementation of the UUID v7 algorithm

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terror 2024-06-20 19:32:24 +12:00
parent ecb7614c9f
commit 88faf60c0d
1 changed files with 61 additions and 10 deletions
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71
tool/net/lfuncs.c
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@ -859,17 +859,68 @@ int LuaUuidV4(lua_State *L) {
}
int LuaUuidV7(lua_State *L) {
char uuid_str[37] = {0};
char bin[16], uuid_str[37];
struct timespec ts = timespec_real();
uint64_t time_now = ts.tv_sec * 1000000000 + ts.tv_nsec;
uint64_t random_data = _rand64();
snprintf(uuid_str, 37, "%08x-%04x-%04x-%04x-%012llx",
(uint32_t)(time_now >> 32),
(uint16_t)(time_now >> 16),
(uint16_t)((0x7 << 12) | (time_now >> 4 & 0x0fff)),
(uint16_t)((0b10 << 14 | ((time_now & 0x000f) << 10)) | (random_data & 0x03FF)),
(uint64_t)(random_data >> 4 & 0xFFFFFFFFFFFF)
);
uint64_t unix_ts_ms = (uint64_t)((ts.tv_sec * 1000) + (ts.tv_nsec / 1000000));
int fractional_ms = (int)floor((double)((double)(ts.tv_nsec - (ts.tv_nsec / 1000000) * 1000000)/1000000) * 4096) <<4;
uint64_t rand_b = _rand64();
int rand_a = fractional_ms | (rand_b & 0x000000000000000f); //use the last 4 bits of rand_b
bin[0] = unix_ts_ms >> 050;
bin[1] = unix_ts_ms >> 040;
bin[2] = unix_ts_ms >> 030;
bin[3] = unix_ts_ms >> 020;
bin[4] = unix_ts_ms >> 010;
bin[5] = unix_ts_ms >> 000;
bin[6] = rand_a >> 010;
bin[7] = rand_a >> 000;
bin[8] = rand_b >> 070;
bin[9] = rand_b >> 060;
bin[10] = rand_b >> 050;
bin[11] = rand_b >> 040;
bin[12] = rand_b >> 030;
bin[13] = rand_b >> 020;
bin[14] = rand_b >> 010;
bin[15] = rand_b >> 000;
uuid_str[0] = "0123456789abcdef"[(bin[0] & 0xf0) >>4];
uuid_str[1] = "0123456789abcdef"[(bin[0] & 0x0f)];
uuid_str[2] = "0123456789abcdef"[(bin[1] & 0xf0) >>4];
uuid_str[3] = "0123456789abcdef"[(bin[1] & 0x0f)];
uuid_str[4] = "0123456789abcdef"[(bin[2] & 0xf0) >>4];
uuid_str[5] = "0123456789abcdef"[(bin[2] & 0x0f)];
uuid_str[6] = "0123456789abcdef"[(bin[3] & 0xf0) >>4];
uuid_str[7] = "0123456789abcdef"[(bin[3] & 0x0f)];
uuid_str[8] = '-';
uuid_str[9] = "0123456789abcdef"[(bin[4] & 0xf0) >>4];
uuid_str[10] = "0123456789abcdef"[(bin[4] & 0x0f)];
uuid_str[11] = "0123456789abcdef"[(bin[5] & 0xf0) >>4];
uuid_str[12] = "0123456789abcdef"[(bin[5] & 0x0f)];
uuid_str[13] = '-';
uuid_str[14] = '7';
uuid_str[15] = "0123456789abcdef"[(bin[6] & 0xf0) >>4];
uuid_str[16] = "0123456789abcdef"[(bin[6] & 0x0f)];
uuid_str[17] = "0123456789abcdef"[(bin[7] & 0xf0) >>4];
uuid_str[18] = '-';
uuid_str[19] = "0123456789abcdef"[(0x8 | ((bin[7] & 0x0f) >>2))];
uuid_str[20] = "0123456789abcdef"[(bin[7] & 0x03) | (bin[8] & 0xf0) >>6];
uuid_str[21] = "0123456789abcdef"[(bin[8] & 0x0f)];
uuid_str[22] = "0123456789abcdef"[(bin[9] & 0xf0) >>4];
uuid_str[23] = '-';
uuid_str[24] = "0123456789abcdef"[(bin[9] & 0x0f)];
uuid_str[25] = "0123456789abcdef"[(bin[10] & 0xf0) >>4];
uuid_str[26] = "0123456789abcdef"[(bin[10] & 0x0f)];
uuid_str[27] = "0123456789abcdef"[(bin[11] & 0xf0) >>4];
uuid_str[28] = "0123456789abcdef"[(bin[11] & 0x0f)];
uuid_str[29] = "0123456789abcdef"[(bin[12] & 0xf0) >>4];
uuid_str[30] = "0123456789abcdef"[(bin[12] & 0x0f)];
uuid_str[31] = "0123456789abcdef"[(bin[13] & 0xf0) >>4];
uuid_str[32] = "0123456789abcdef"[(bin[13] & 0x0f)];
uuid_str[33] = "0123456789abcdef"[(bin[14] & 0xf0) >>4];
uuid_str[34] = "0123456789abcdef"[(bin[14] & 0x0f)];
uuid_str[35] = "0123456789abcdef"[(bin[15] & 0xf0) >>4];
uuid_str[36] = '\0';
lua_pushfstring(L, uuid_str);
return 1;
}