| /** |
| * Licensed to the Apache Software Foundation (ASF) under one |
| * or more contributor license agreements. See the NOTICE file |
| * distributed with this work for additional information |
| * regarding copyright ownership. The ASF licenses this file |
| * to you 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. |
| */ |
| |
| #ifndef APACHE_HTRACE_SPAN_ID_H |
| #define APACHE_HTRACE_SPAN_ID_H |
| |
| /** |
| * @file span_id.h |
| * |
| * Functions related to HTrace span IDs. |
| * |
| * This is an internal header, not intended for external use. |
| */ |
| |
| #include <stdint.h> // for uint64_t |
| #include <unistd.h> // for size_t |
| |
| struct cmp_ctx_s; |
| struct random_src; |
| |
| /** |
| * Length of an HTrace span ID in hexadecimal string form. |
| */ |
| #define HTRACE_SPAN_ID_STRING_LENGTH 32 |
| |
| /** |
| * The number of bytes in the HTrace span ID |
| */ |
| #define HTRACE_SPAN_ID_NUM_BYTES 16 |
| |
| /** |
| * The invalid span ID, which is all zeroes. |
| */ |
| extern const struct htrace_span_id INVALID_SPAN_ID; |
| |
| /** |
| * The HTrace span id. |
| */ |
| struct htrace_span_id { |
| uint64_t high; |
| uint64_t low; |
| }; |
| |
| /** |
| * Parse a string containing an HTrace span ID. |
| * |
| * @param id The HTrace span ID to fill in. |
| * @param str The string to parse. |
| * |
| */ |
| void htrace_span_id_parse(struct htrace_span_id *id, const char *str, |
| char *err, size_t err_len); |
| |
| /** |
| * Write an HTrace span ID to a string. |
| * |
| * @param id The HTrace span ID. |
| * @param str Where to put the string. |
| * @param len The length of the string buffer. |
| * @param err The error buffer to be set on failure. |
| * @param err_len Length of the error buffer. |
| * |
| * @return 1 on success; 0 if the length was not long enough, or |
| * there was an internal snprintf error. |
| */ |
| int htrace_span_id_to_str(const struct htrace_span_id *id, |
| char *str, size_t len); |
| |
| /** |
| * Copy an htrace span ID. |
| * |
| * dst and src can be the same. |
| * |
| * @param dst The destination span ID. |
| * @param src The source span ID. |
| */ |
| void htrace_span_id_copy(struct htrace_span_id *dst, |
| const struct htrace_span_id *src); |
| |
| /** |
| * Write this span ID to the provided CMP context. |
| * |
| * @param span The span. |
| * @param ctx The CMP context. |
| * |
| * @return 0 on failure; 1 on success. |
| */ |
| int htrace_span_id_write_msgpack(const struct htrace_span_id *id, |
| struct cmp_ctx_s *ctx); |
| |
| /** |
| * Read this span ID from the provided CMP context. |
| * |
| * @param span The span. |
| * @param ctx The CMP context. |
| * |
| * @return 0 on failure; 1 on success. |
| */ |
| int htrace_span_id_read_msgpack(struct htrace_span_id *id, |
| struct cmp_ctx_s *ctx); |
| |
| /** |
| * Generate a new span ID. |
| * |
| * @param id The span ID to alter. |
| * @param rnd The random source. |
| * @param parent The parent span ID, or null if there is none. |
| */ |
| void htrace_span_id_generate(struct htrace_span_id *id, struct random_src *rnd, |
| const struct htrace_span_id *parent); |
| |
| /** |
| * Set a span ID to the invalid span ID by clearing it. |
| * |
| * @param id The span ID to clear. |
| */ |
| void htrace_span_id_clear(struct htrace_span_id *id); |
| |
| /** |
| * Compare two span IDs. |
| * |
| * @param a The first span ID. |
| * @param b The second span ID. |
| * |
| * @return A number less than 0 if the first span ID is less; |
| * A number greater than 0 if the first span ID is greater; |
| * 0 if the span IDs are equal. |
| */ |
| int htrace_span_id_compare(const struct htrace_span_id *a, |
| const struct htrace_span_id *b); |
| |
| #endif |
| |
| // vim: ts=4:sw=4:et |