JavaScriptCore/wtf/text/StringStatics.cpp
changeset 0 4f2f89ce4247
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/JavaScriptCore/wtf/text/StringStatics.cpp	Fri Sep 17 09:02:29 2010 +0300
@@ -0,0 +1,96 @@
+/*
+ * Copyright (C) 2010 Apple Inc. All Rights Reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. 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.
+ *
+ * THIS SOFTWARE IS PROVIDED BY APPLE INC. ``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 APPLE INC. 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.
+ */
+
+#include "config.h"
+
+#ifdef SKIP_STATIC_CONSTRUCTORS_ON_GCC
+#define ATOMICSTRING_HIDE_GLOBALS 1
+#endif
+
+#include "AtomicString.h"
+#include "StaticConstructors.h"
+#include "StringImpl.h"
+
+namespace WebCore {
+
+StringImpl* StringImpl::empty()
+{
+    // FIXME: This works around a bug in our port of PCRE, that a regular expression
+    // run on the empty string may still perform a read from the first element, and
+    // as such we need this to be a valid pointer. No code should ever be reading
+    // from a zero length string, so this should be able to be a non-null pointer
+    // into the zero-page.
+    // Replace this with 'reinterpret_cast<UChar*>(static_cast<intptr_t>(1))' once
+    // PCRE goes away.
+    static UChar emptyUCharData = 0;
+    DEFINE_STATIC_LOCAL(StringImpl, emptyString, (&emptyUCharData, 0, ConstructStaticString));
+    return &emptyString;
+}
+/*
+JS_EXPORTDATA DEFINE_GLOBAL(AtomicString, nullAtom)
+JS_EXPORTDATA DEFINE_GLOBAL(AtomicString, emptyAtom, "")
+JS_EXPORTDATA DEFINE_GLOBAL(AtomicString, textAtom, "#text")
+JS_EXPORTDATA DEFINE_GLOBAL(AtomicString, commentAtom, "#comment")
+JS_EXPORTDATA DEFINE_GLOBAL(AtomicString, starAtom, "*")
+JS_EXPORTDATA DEFINE_GLOBAL(AtomicString, xmlAtom, "xml")
+JS_EXPORTDATA DEFINE_GLOBAL(AtomicString, xmlnsAtom, "xmlns")
+*/
+AtomicString nullAtom1;
+AtomicString emptyAtom1;
+AtomicString textAtom1;
+AtomicString commentAtom1;
+AtomicString starAtom1;
+AtomicString xmlAtom1;
+AtomicString xmlnsAtom1;
+
+void AtomicString::init()
+{
+    static bool initialized;
+    if (!initialized) {
+        // Initialization is not thread safe, so this function must be called from the main thread first.
+        ASSERT(isMainThread());
+
+        // Use placement new to initialize the globals.
+        new ((void*)&nullAtom1) AtomicString;
+        new ((void*)&emptyAtom1) AtomicString("");
+        new ((void*)&textAtom1) AtomicString("#text");
+        new ((void*)&commentAtom1) AtomicString("#comment");
+        new ((void*)&starAtom1) AtomicString("*");
+        new ((void*)&xmlAtom1) AtomicString("xml");
+        new ((void*)&xmlnsAtom1) AtomicString("xmlns");
+
+        initialized = true;
+    }
+}
+
+const AtomicString& AtomicString::nullAtom2() { return nullAtom1;}
+const AtomicString& AtomicString::emptyAtom2() { return emptyAtom1;}
+const AtomicString& AtomicString::textAtom2() { return textAtom1;}
+const AtomicString& AtomicString::commentAtom2() { return commentAtom1;}
+const AtomicString& AtomicString::starAtom2() { return starAtom1;}
+const AtomicString& AtomicString::xmlAtom2() { return xmlAtom1;}
+const AtomicString& AtomicString::xmlnsAtom2() { return xmlnsAtom1;}
+
+}