1 files changed, 66 insertions, 0 deletions
diff --git a/xpcom/base/NSPRLogModulesParser.cpp b/xpcom/base/NSPRLogModulesParser.cpp
new file mode 100644
index 0000000000..44fb50dbc7
--- /dev/null
+++ b/xpcom/base/NSPRLogModulesParser.cpp
@@ -0,0 +1,66 @@
+/* -*- Mode: C++; tab-width: 8; 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 "NSPRLogModulesParser.h"
+
+#include "mozilla/Tokenizer.h"
+
+const char kDelimiters[] = ", ";
+const char kAdditionalWordChars[] = "_-.*";
+
+namespace mozilla {
+
+void NSPRLogModulesParser(
+    const char* aLogModules,
+    const std::function<void(const char*, LogLevel, int32_t)>& aCallback) {
+  if (!aLogModules) {
+    return;
+  }
+
+  Tokenizer parser(aLogModules, kDelimiters, kAdditionalWordChars);
+  nsAutoCString moduleName;
+
+  Tokenizer::Token rustModSep =
+      parser.AddCustomToken("::", Tokenizer::CASE_SENSITIVE);
+
+  auto readModuleName = [&](nsAutoCString& moduleName) -> bool {
+    moduleName.Truncate();
+    nsDependentCSubstring sub;
+    parser.Record();
+    // If the name doesn't include at least one word, we've reached the end.
+    if (!parser.ReadWord(sub)) {
+      return false;
+    }
+    // We will exit this loop if when any of the condition fails
+    while (parser.Check(rustModSep) && parser.ReadWord(sub)) {
+    }
+    // Claim will include characters of the last sucessfully read item
+    parser.Claim(moduleName, Tokenizer::INCLUDE_LAST);
+    return true;
+  };
+
+  // Format: LOG_MODULES="Foo:2,Bar, Baz:5,rust_crate::mod::file:5"
+  while (readModuleName(moduleName)) {
+    // Next should be :<level>, default to Error if not provided.
+    LogLevel logLevel = LogLevel::Error;
+    int32_t levelValue = 0;
+    if (parser.CheckChar(':')) {
+      // NB: If a level isn't provided after the ':' we assume the default
+      //     Error level is desired. This differs from NSPR which will stop
+      //     processing the log module string in this case.
+      if (parser.ReadSignedInteger(&levelValue)) {
+        logLevel = ToLogLevel(levelValue);
+      }
+    }
+
+    aCallback(moduleName.get(), logLevel, levelValue);
+
+    // Skip ahead to the next token.
+    parser.SkipWhites();
+  }
+}
+
+}  // namespace mozilla