1 files changed, 101 insertions, 0 deletions
diff --git a/mozglue/baseprofiler/core/ProfileJSONWriter.cpp b/mozglue/baseprofiler/core/ProfileJSONWriter.cpp
new file mode 100644
index 0000000000..dc51f6958e
--- /dev/null
+++ b/mozglue/baseprofiler/core/ProfileJSONWriter.cpp
@@ -0,0 +1,101 @@
+/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* vim: set ts=8 sts=2 et sw=2 tw=80: */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#include "mozilla/BaseProfileJSONWriter.h"
+
+namespace mozilla::baseprofiler {
+
+UniqueJSONStrings::UniqueJSONStrings(FailureLatch& aFailureLatch)
+    : mStringTableWriter(aFailureLatch) {
+  mStringTableWriter.StartBareList();
+  if (const char* failure = mStringTableWriter.GetFailure(); failure) {
+    ClearAndSetFailure(failure);
+    return;
+  }
+}
+
+UniqueJSONStrings::UniqueJSONStrings(FailureLatch& aFailureLatch,
+                                     const UniqueJSONStrings& aOther,
+                                     ProgressLogger aProgressLogger)
+    : mStringTableWriter(aFailureLatch) {
+  using namespace mozilla::literals::ProportionValue_literals;  // For `10_pc`.
+
+  if (mStringTableWriter.Failed()) {
+    return;
+  }
+
+  if (const char* failure = aOther.GetFailure(); failure) {
+    ClearAndSetFailure(failure);
+    return;
+  }
+
+  mStringTableWriter.StartBareList();
+  uint32_t count = aOther.mStringHashToIndexMap.count();
+  if (count != 0) {
+    if (!mStringHashToIndexMap.reserve(count)) {
+      ClearAndSetFailure("Cannot reserve UniqueJSONStrings map storage");
+      return;
+    }
+    auto iter = aOther.mStringHashToIndexMap.iter();
+    for (auto&& [unusedIndex, progressLogger] :
+         aProgressLogger.CreateLoopSubLoggersFromTo(
+             10_pc, 90_pc, count, "Copying unique strings...")) {
+      (void)unusedIndex;
+      if (iter.done()) {
+        break;
+      }
+      mStringHashToIndexMap.putNewInfallible(iter.get().key(),
+                                             iter.get().value());
+      iter.next();
+    }
+    aProgressLogger.SetLocalProgress(90_pc, "Copied unique strings");
+    mStringTableWriter.CopyAndSplice(
+        aOther.mStringTableWriter.ChunkedWriteFunc());
+    if (const char* failure = aOther.GetFailure(); failure) {
+      ClearAndSetFailure(failure);
+    }
+    aProgressLogger.SetLocalProgress(100_pc, "Spliced unique strings");
+  }
+}
+
+UniqueJSONStrings::~UniqueJSONStrings() = default;
+
+void UniqueJSONStrings::SpliceStringTableElements(
+    SpliceableJSONWriter& aWriter) {
+  aWriter.TakeAndSplice(mStringTableWriter.TakeChunkedWriteFunc());
+}
+
+void UniqueJSONStrings::ClearAndSetFailure(std::string aFailure) {
+  mStringTableWriter.SetFailure(std::move(aFailure));
+  mStringHashToIndexMap.clear();
+}
+
+Maybe<uint32_t> UniqueJSONStrings::GetOrAddIndex(const Span<const char>& aStr) {
+  if (Failed()) {
+    return Nothing{};
+  }
+
+  uint32_t count = mStringHashToIndexMap.count();
+  HashNumber hash = HashString(aStr.data(), aStr.size());
+  auto entry = mStringHashToIndexMap.lookupForAdd(hash);
+  if (entry) {
+    MOZ_ASSERT(entry->value() < count);
+    return Some(entry->value());
+  }
+
+  if (!mStringHashToIndexMap.add(entry, hash, count)) {
+    ClearAndSetFailure("OOM in UniqueJSONStrings::GetOrAddIndex adding a map");
+    return Nothing{};
+  }
+  mStringTableWriter.StringElement(aStr);
+  if (const char* failure = mStringTableWriter.GetFailure(); failure) {
+    ClearAndSetFailure(failure);
+    return Nothing{};
+  }
+  return Some(count);
+}
+
+}  // namespace mozilla::baseprofiler