xref: /aosp_15_r20/external/pigweed/pw_trace_tokenized/trace_buffer_log.cc (revision 61c4878ac05f98d0ceed94b57d316916de578985)
1 // Copyright 2020 The Pigweed Authors
2 //
3 // Licensed under the Apache License, Version 2.0 (the "License"); you may not
4 // use this file except in compliance with the License. You may obtain a copy of
5 // the License at
6 //
7 //     https://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, WITHOUT
11 // WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
12 // License for the specific language governing permissions and limitations under
13 // the License.
14 //==============================================================================
15 //
16 #include "pw_trace_tokenized/trace_buffer_log.h"
17 
18 #include "pw_base64/base64.h"
19 #include "pw_log/log.h"
20 #include "pw_span/span.h"
21 #include "pw_string/string_builder.h"
22 #include "pw_trace_tokenized/trace_buffer.h"
23 
24 namespace pw {
25 namespace trace {
26 namespace {
27 
28 constexpr int kMaxEntrySize = PW_TRACE_BUFFER_MAX_BLOCK_SIZE_BYTES;
29 constexpr int kMaxEntrySizeBase64 = pw::base64::EncodedSize(kMaxEntrySize);
30 constexpr int kLineLength = 80;
31 
32 class ScopedTracePause {
33  public:
ScopedTracePause()34   ScopedTracePause() : was_enabled_(pw_trace_IsEnabled()) {
35     PW_TRACE_SET_ENABLED(false);
36   }
~ScopedTracePause()37   ~ScopedTracePause() { PW_TRACE_SET_ENABLED(was_enabled_); }
38 
39  private:
40   bool was_enabled_;
41 };
42 
43 }  // namespace
44 
DumpTraceBufferToLog()45 pw::Status DumpTraceBufferToLog() {
46   std::byte line_buffer[kLineLength] = {};
47   std::byte entry_buffer[kMaxEntrySize + 1] = {};
48   char entry_base64_buffer[kMaxEntrySizeBase64] = {};
49   pw::StringBuilder line_builder(line_buffer);
50   ScopedTracePause pause_trace;
51   pw::ring_buffer::PrefixedEntryRingBuffer* trace_buffer =
52       pw::trace::GetBuffer();
53   size_t bytes_read = 0;
54   PW_LOG_INFO("[TRACE] begin");
55   while (trace_buffer->PeekFront(span(entry_buffer).subspan(1), &bytes_read) !=
56          pw::Status::OutOfRange()) {
57     trace_buffer->PopFront()
58         .IgnoreError();  // TODO: b/242598609 - Handle Status properly
59     entry_buffer[0] = static_cast<std::byte>(bytes_read);
60     // The entry buffer is formatted as (size, entry) with an extra byte as
61     // a header to the entry. The calcuation of bytes_read + 1 represents
62     // the extra size header.
63     size_t to_write = pw::base64::Encode(span(entry_buffer, bytes_read + 1),
64                                          span(entry_base64_buffer));
65     size_t space_left = line_builder.max_size() - line_builder.size();
66     size_t written = 0;
67     while (to_write - written >= space_left) {
68       line_builder.append(entry_base64_buffer + written, space_left);
69       PW_LOG_INFO("[TRACE] data: %s", line_builder.c_str());
70       line_builder.clear();
71       written += space_left;
72       space_left = line_builder.max_size();
73     }
74     line_builder.append(entry_base64_buffer + written, to_write - written);
75   }
76   if (!line_builder.empty()) {
77     PW_LOG_INFO("[TRACE] data: %s", line_builder.c_str());
78   }
79   PW_LOG_INFO("[TRACE] end");
80   return pw::OkStatus();
81 }
82 
83 }  // namespace trace
84 }  // namespace pw
85