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Diffstat (limited to 'src/core/ext/census/trace_context.h')
| -rw-r--r-- | src/core/ext/census/trace_context.h | 68 |
1 files changed, 68 insertions, 0 deletions
diff --git a/src/core/ext/census/trace_context.h b/src/core/ext/census/trace_context.h new file mode 100644 index 0000000000..ee71fef460 --- /dev/null +++ b/src/core/ext/census/trace_context.h @@ -0,0 +1,68 @@ +/* + * + * Copyright 2016, Google Inc. + * All rights reserved. + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions are + * met: + * + * * Redistributions of source code must retain the above copyright + * notice, this list of conditions and the following disclaimer. + * * Redistributions in binary form must reproduce the above + * copyright notice, this list of conditions and the following disclaimer + * in the documentation and/or other materials provided with the + * distribution. + * * Neither the name of Google Inc. nor the names of its + * contributors may be used to endorse or promote products derived from + * this software without specific prior written permission. + * + * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS + * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT + * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR + * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT + * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, + * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT + * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, + * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY + * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT + * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE + * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. + * + */ + +/* Functions for manipulating trace contexts as defined in + src/proto/census/trace.proto */ +#ifndef GRPC_CORE_EXT_CENSUS_TRACE_CONTEXT_H +#define GRPC_CORE_EXT_CENSUS_TRACE_CONTEXT_H + +#include "src/core/ext/census/gen/trace_context.pb.h" + +/* Maximum number of bytes required to encode a TraceContext (31) +1 byte for trace_id field +1 byte for trace_id length +1 byte for trace_id.hi field +8 bytes for trace_id.hi (uint64_t) +1 byte for trace_id.lo field +8 bytes for trace_id.lo (uint64_t) +1 byte for span_id field +8 bytes for span_id (uint64_t) +1 byte for is_sampled field +1 byte for is_sampled (bool) */ +#define TRACE_MAX_CONTEXT_SIZE 31 + +/* Encode a trace context (ctxt) into proto format to the buffer provided. The +size of buffer must be at least TRACE_MAX_CONTEXT_SIZE. On success, returns the +number of bytes successfully encoded into buffer. On failure, returns 0. */ +size_t encode_trace_context(google_trace_TraceContext *ctxt, uint8_t *buffer, + const size_t buf_size); + +/* Decode a proto-encoded TraceContext from the provided buffer into the +TraceContext structure (ctxt). The function expects to be supplied the number +of bytes to be read from buffer (nbytes). This function will also validate that +the TraceContext has a span_id and a trace_id, and will return false if either +of these do not exist. On success, returns true and false otherwise. */ +bool decode_trace_context(google_trace_TraceContext *ctxt, uint8_t *buffer, + const size_t nbytes); + +#endif |