[blink]: Annotate StringImpl::createStatic leak for LeakSanitizer.

Source/wtf/LeakAnnotations.h

+/*
+ * Copyright (C) 2013 Google Inc. All rights reserved.
+ * Copyright (C) 2013 Samsung Electronics. All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are
+ * met:
+ *
+ *     * Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ *     * Redistributions in binary form must reproduce the above
+ * copyright notice, this list of conditions and the following disclaimer
+ * in the documentation and/or other materials provided with the
+ * distribution.
+ *     * Neither the name of Google Inc. nor the names of its
+ * contributors may be used to endorse or promote products derived from
+ * this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+ * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+ * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+ * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+ * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#ifndef WTF_LeakAnnotations_h
+#define WTF_LeakAnnotations_h
+
+// This file defines macros which can be used to annotate intentional memory
+// leaks. Support for annotations is implemented in HeapChecker and
+// LeakSanitizer. Annotated objects will be treated as a source of live
+// pointers, i.e. any heap objects reachable by following pointers from an
+// annotated object will not be reported as leaks.
+//
+// WTF_ANNOTATE_SCOPED_MEMORY_LEAK: all allocations made in the current scope
+// will be annotated as leaks.
+// WTF_ANNOTATE_LEAKING_OBJECT_PTR(X): the heap object referenced by pointer X
+// will be annotated as a leak.
+//
+// Note that HeapChecker will report a fatal error if an object which has been
+// annotated with ANNOTATE_LEAKING_OBJECT_PTR is later deleted (but
+// LeakSanitizer won't).
+
+#include "wtf/Noncopyable.h"
+
+namespace WTF {
+
+#if USE(LEAK_SANITIZER)
+extern "C" {
+void __lsan_disable();
+void __lsan_enable();
+void __lsan_ignore_object(const void *p);
+} // extern "C"
+
+class LeakSanitizerDisabler {
+    WTF_MAKE_NONCOPYABLE(LeakSanitizerDisabler);
+public:
+    LeakSanitizerDisabler()
+    {
+        __lsan_disable();
+    }
+
+    ~LeakSanitizerDisabler()
+    {
+        __lsan_enable();
+    }
+};
+
+#define WTF_ANNOTATE_SCOPED_MEMORY_LEAK \
+    LeakSanitizerDisabler leakSanitizerDisabler; static_cast<void>(0)
+
+#define WTF_ANNOTATE_LEAKING_OBJECT_PTR(X) \
+    __lsan_ignore_object(X)
+
+#else // USE(LEAK_SANITIZER)
+
+// If Leak Sanitizer is not being used, the annotations should be no-ops.
+#define WTF_ANNOTATE_SCOPED_MEMORY_LEAK
+#define WTF_ANNOTATE_LEAKING_OBJECT_PTR(X)
+
+#endif // USE(LEAK_SANITIZER)
+
+} // namespace WTF
+
+#endif // WTF_LeakAnnotations_h