diff options
Diffstat (limited to 'src/uuid.c')
-rw-r--r-- | src/uuid.c | 88 |
1 files changed, 88 insertions, 0 deletions
diff --git a/src/uuid.c b/src/uuid.c new file mode 100644 index 00000000..c682080f --- /dev/null +++ b/src/uuid.c @@ -0,0 +1,88 @@ +/* + * Copyright (C) 2016-2019 "IoT.bzh" + * Author: José Bollo <jose.bollo@iot.bzh> + * + * Licensed under the Apache License, Version 2.0 (the "License"); + * you may not use this file except in compliance with the License. + * You may obtain a copy of the License at + * + * http://www.apache.org/licenses/LICENSE-2.0 + * + * Unless required by applicable law or agreed to in writing, software + * distributed under the License is distributed on an "AS IS" BASIS, + * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. + * See the License for the specific language governing permissions and + * limitations under the License. + */ + +#include <stdint.h> +#include <unistd.h> +#include <stdlib.h> +#include <string.h> + +#include <uuid/uuid.h> + +#include "uuid.h" + +/** + * generate a new fresh 'uuid' + */ +void uuid_new_binary(uuid_binary_t uuid) +{ +#if defined(USE_UUID_GENERATE) + uuid_generate(uuid); +#else + struct timespec ts; + static uint16_t pid; + static uint16_t counter; + static char state[32]; + static struct random_data rdata; + + int32_t x; + clock_gettime(CLOCK_MONOTONIC_RAW, &ts); + if (pid == 0) { + pid = (uint16_t)getpid(); + counter = (uint16_t)(ts.tv_nsec >> 8); + rdata.state = NULL; + initstate_r((((unsigned)pid) << 16) + ((unsigned)counter), + state, sizeof state, &rdata); + } + ts.tv_nsec ^= (long)ts.tv_sec; + if (++counter == 0) + counter = 1; + + uuid[0] = (char)(ts.tv_nsec >> 24); + uuid[1] = (char)(ts.tv_nsec >> 16); + uuid[2] = (char)(ts.tv_nsec >> 8); + uuid[3] = (char)(ts.tv_nsec); + + uuid[4] = (char)(pid >> 8); + uuid[5] = (char)(pid); + + random_r(&rdata, &x); + uuid[6] = (char)(((x >> 16) & 0x0f) | 0x40); /* pseudo-random version */ + uuid[7] = (char)(x >> 8); + + random_r(&rdata, &x); + uuid[8] = (char)(((x >> 16) & 0x3f) | 0x80); /* variant RFC4122 */ + uuid[9] = (char)(x >> 8); + + random_r(&rdata, &x); + uuid[10] = (char)(x >> 16); + uuid[11] = (char)(x >> 8); + + random_r(&rdata, &x); + uuid[12] = (char)(x >> 16); + uuid[13] = (char)(x >> 8); + + uuid[14] = (char)(counter >> 8); + uuid[15] = (char)(counter); +#endif +} + +void uuid_new_stringz(uuid_stringz_t uuid) +{ + uuid_t newuuid; + uuid_new_binary(newuuid); + uuid_unparse_lower(newuuid, uuid); +} |