mozglue/baseprofiler/core/ProfileJSONWriter.cpp

   1 /* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
   2 /* vim: set ts=8 sts=2 et sw=2 tw=80: */
   3 /* This Source Code Form is subject to the terms of the Mozilla Public
   4  * License, v. 2.0. If a copy of the MPL was not distributed with this
   5  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
   6
   7 #include "mozilla/BaseProfileJSONWriter.h"
   8
   9 namespace mozilla::baseprofiler {
  10
  11 UniqueJSONStrings::UniqueJSONStrings(FailureLatch& aFailureLatch)
  12     : mStringTableWriter(aFailureLatch) {
  13   mStringTableWriter.StartBareList();
  14   if (const char* failure = mStringTableWriter.GetFailure(); failure) {
  15     ClearAndSetFailure(failure);
  16     return;
  17   }
  18 }
  19
  20 UniqueJSONStrings::UniqueJSONStrings(FailureLatch& aFailureLatch,
  21                                      const UniqueJSONStrings& aOther,
  22                                      ProgressLogger aProgressLogger)
  23     : mStringTableWriter(aFailureLatch) {
  24   using namespace mozilla::literals::ProportionValue_literals;  // For `10_pc`.
  25
  26   if (mStringTableWriter.Failed()) {
  27     return;
  28   }
  29
  30   if (const char* failure = aOther.GetFailure(); failure) {
  31     ClearAndSetFailure(failure);
  32     return;
  33   }
  34
  35   mStringTableWriter.StartBareList();
  36   uint32_t count = aOther.mStringHashToIndexMap.count();
  37   if (count != 0) {
  38     if (!mStringHashToIndexMap.reserve(count)) {
  39       ClearAndSetFailure("Cannot reserve UniqueJSONStrings map storage");
  40       return;
  41     }
  42     auto iter = aOther.mStringHashToIndexMap.iter();
  43     for (auto&& [unusedIndex, progressLogger] :
  44          aProgressLogger.CreateLoopSubLoggersFromTo(
  45              10_pc, 90_pc, count, "Copying unique strings...")) {
  46       (void)unusedIndex;
  47       if (iter.done()) {
  48         break;
  49       }
  50       mStringHashToIndexMap.putNewInfallible(iter.get().key(),
  51                                              iter.get().value());
  52       iter.next();
  53     }
  54     aProgressLogger.SetLocalProgress(90_pc, "Copied unique strings");
  55     mStringTableWriter.CopyAndSplice(
  56         aOther.mStringTableWriter.ChunkedWriteFunc());
  57     if (const char* failure = aOther.GetFailure(); failure) {
  58       ClearAndSetFailure(failure);
  59     }
  60     aProgressLogger.SetLocalProgress(100_pc, "Spliced unique strings");
  61   }
  62 }
  63
  64 UniqueJSONStrings::~UniqueJSONStrings() = default;
  65
  66 void UniqueJSONStrings::SpliceStringTableElements(
  67     SpliceableJSONWriter& aWriter) {
  68   aWriter.TakeAndSplice(mStringTableWriter.TakeChunkedWriteFunc());
  69 }
  70
  71 void UniqueJSONStrings::ClearAndSetFailure(std::string aFailure) {
  72   mStringTableWriter.SetFailure(std::move(aFailure));
  73   mStringHashToIndexMap.clear();
  74 }
  75
  76 Maybe<uint32_t> UniqueJSONStrings::GetOrAddIndex(const Span<const char>& aStr) {
  77   if (Failed()) {
  78     return Nothing{};
  79   }
  80
  81   uint32_t count = mStringHashToIndexMap.count();
  82   HashNumber hash = HashString(aStr.data(), aStr.size());
  83   auto entry = mStringHashToIndexMap.lookupForAdd(hash);
  84   if (entry) {
  85     MOZ_ASSERT(entry->value() < count);
  86     return Some(entry->value());
  87   }
  88
  89   if (!mStringHashToIndexMap.add(entry, hash, count)) {
  90     ClearAndSetFailure("OOM in UniqueJSONStrings::GetOrAddIndex adding a map");
  91     return Nothing{};
  92   }
  93   mStringTableWriter.StringElement(aStr);
  94   if (const char* failure = mStringTableWriter.GetFailure(); failure) {
  95     ClearAndSetFailure(failure);
  96     return Nothing{};
  97   }
  98   return Some(count);
  99 }
 100
 101 }  // namespace mozilla::baseprofiler