1 files changed, 84 insertions, 0 deletions
diff --git a/lib/xray/xray_flags.cpp b/lib/xray/xray_flags.cpp
new file mode 100644
index 000000000000..e4c6906dc443
--- /dev/null
+++ b/lib/xray/xray_flags.cpp
@@ -0,0 +1,84 @@
+//===-- xray_flags.cpp ------------------------------------------*- C++ -*-===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+//
+// This file is a part of XRay, a dynamic runtime instrumentation system.
+//
+// XRay flag parsing logic.
+//===----------------------------------------------------------------------===//
+
+#include "xray_flags.h"
+#include "sanitizer_common/sanitizer_common.h"
+#include "sanitizer_common/sanitizer_flag_parser.h"
+#include "sanitizer_common/sanitizer_libc.h"
+#include "xray_defs.h"
+
+using namespace __sanitizer;
+
+namespace __xray {
+
+Flags xray_flags_dont_use_directly; // use via flags().
+
+void Flags::setDefaults() XRAY_NEVER_INSTRUMENT {
+#define XRAY_FLAG(Type, Name, DefaultValue, Description) Name = DefaultValue;
+#include "xray_flags.inc"
+#undef XRAY_FLAG
+}
+
+void registerXRayFlags(FlagParser *P, Flags *F) XRAY_NEVER_INSTRUMENT {
+#define XRAY_FLAG(Type, Name, DefaultValue, Description)                       \
+  RegisterFlag(P, #Name, Description, &F->Name);
+#include "xray_flags.inc"
+#undef XRAY_FLAG
+}
+
+// This function, as defined with the help of a macro meant to be introduced at
+// build time of the XRay runtime, passes in a statically defined list of
+// options that control XRay. This means users/deployments can tweak the
+// defaults that override the hard-coded defaults in the xray_flags.inc at
+// compile-time using the XRAY_DEFAULT_OPTIONS macro.
+const char *useCompilerDefinedFlags() XRAY_NEVER_INSTRUMENT {
+#ifdef XRAY_DEFAULT_OPTIONS
+  // Do the double-layered string conversion to prevent badly crafted strings
+  // provided through the XRAY_DEFAULT_OPTIONS from causing compilation issues
+  // (or changing the semantics of the implementation through the macro). This
+  // ensures that we convert whatever XRAY_DEFAULT_OPTIONS is defined as a
+  // string literal.
+  return SANITIZER_STRINGIFY(XRAY_DEFAULT_OPTIONS);
+#else
+  return "";
+#endif
+}
+
+void initializeFlags() XRAY_NEVER_INSTRUMENT {
+  SetCommonFlagsDefaults();
+  auto *F = flags();
+  F->setDefaults();
+
+  FlagParser XRayParser;
+  registerXRayFlags(&XRayParser, F);
+  RegisterCommonFlags(&XRayParser);
+
+  // Use options defaulted at compile-time for the runtime.
+  const char *XRayCompileFlags = useCompilerDefinedFlags();
+  XRayParser.ParseString(XRayCompileFlags);
+
+  // Override from environment variables.
+  XRayParser.ParseStringFromEnv("XRAY_OPTIONS");
+
+  // Override from command line.
+  InitializeCommonFlags();
+
+  if (Verbosity())
+    ReportUnrecognizedFlags();
+
+  if (common_flags()->help) {
+    XRayParser.PrintFlagDescriptions();
+  }
+}
+
+} // namespace __xray