xref: /aosp_15_r20/external/federated-compute/fcp/tracing/text_tracing_span_impl.h (revision 14675a029014e728ec732f129a32e299b2da0601)
1 // Copyright 2019 Google LLC
2 //
3 // Licensed under the Apache License, Version 2.0 (the "License");
4 // you may not use this file except in compliance with the License.
5 // You may obtain a copy of the License at
6 //
7 //      http://www.apache.org/licenses/LICENSE-2.0
8 //
9 // Unless required by applicable law or agreed to in writing, software
10 // distributed under the License is distributed on an "AS IS" BASIS,
11 // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
12 // See the License for the specific language governing permissions and
13 // limitations under the License.
14 
15 #ifndef FCP_TRACING_TEXT_TRACING_SPAN_IMPL_H_
16 #define FCP_TRACING_TEXT_TRACING_SPAN_IMPL_H_
17 
18 #include <atomic>
19 #include <optional>
20 #include <string>
21 #include <utility>
22 
23 #include "fcp/tracing/text_tracing_recorder_impl.h"
24 #include "fcp/tracing/tracing_span_impl.h"
25 #include "flatbuffers/flatbuffers.h"
26 
27 namespace fcp {
28 namespace tracing_internal {
29 
30 // Basic tracing span implementation that owns the flatbuf representing the
31 // current span.
32 class TextTracingSpanImpl : public TracingSpanImpl {
33  public:
34   // Constructs a TextTracingSpanImpl for a child span from a serialized flatbuf
35   // and TracingTraitsBase which provides more context about the flatbuf table.
TextTracingSpanImpl(std::shared_ptr<TextTracingRecorderImpl> recorder,const flatbuffers::DetachedBuffer & buf,const TracingTraitsBase & traits,TracingSpanId id,TracingSpanId parent_id)36   TextTracingSpanImpl(std::shared_ptr<TextTracingRecorderImpl> recorder,
37                       const flatbuffers::DetachedBuffer& buf,
38                       const TracingTraitsBase& traits, TracingSpanId id,
39                       TracingSpanId parent_id)
40       : id_(id),
41         recorder_shared_ptr_(std::move(recorder)),
42         buf_text_{traits.Name(), traits.TextFormat(buf)} {
43     recorder_ = recorder_shared_ptr_.get();
44     recorder_->BeginSpan(id, parent_id, buf_text_.name, buf_text_.text_format);
45   }
46 
47   // Constructs a TextTracingSpanImpl for root span.
TextTracingSpanImpl(TextTracingRecorderImpl * recorder)48   explicit TextTracingSpanImpl(TextTracingRecorderImpl* recorder)
49       : id_(0), recorder_(recorder), buf_text_{} {
50     recorder_->BeginSpan(TracingSpanId(0), TracingSpanId(0), buf_text_.name,
51                          buf_text_.text_format);
52   }
53   ~TextTracingSpanImpl() override;
54 
55   // Logs an event in the current tracing span.
56   void TraceImpl(flatbuffers::DetachedBuffer&& buf,
57                  const TracingTraitsBase& traits) override;
58 
59   TracingSpanRef Ref() override;
60 
61  private:
62   struct SpanText {
63     std::string name;
64     std::string text_format;
65   };
66   TracingSpanId id_;
67   TextTracingRecorderImpl* recorder_;
68 
69   // For non-root span the following keeps recorder alive, if set,
70   // this holds the same value as recorder_. Since root span is owned directly
71   // by the recorder we can't store shared_ptr for it here to avoid a loop.
72   std::shared_ptr<TextTracingRecorderImpl> recorder_shared_ptr_;
73 
74   // Human readable text describing the flatbuffer representing the current
75   // span; empty if this is the root span.
76   SpanText buf_text_;
77 };
78 
79 }  // namespace tracing_internal
80 }  // namespace fcp
81 
82 #endif  // FCP_TRACING_TEXT_TRACING_SPAN_IMPL_H_
83