Share link header parsing code between blink and content.

third_party/WebKit/Source/platform/network/LinkHeader.cpp

+// Copyright 2015 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#include "platform/network/LinkHeader.h"
+
+#include "components/link_header_util/link_header_util.h"
+#include "platform/ParsingUtilities.h"
+
+namespace blink {
+
+// Verify that the parameter is a link-extension which according to spec doesn't have to have a value.
+static bool isExtensionParameter(LinkHeader::LinkParameterName name)
+{
+    return name >= LinkHeader::LinkParameterUnknown;
+}
+
+static LinkHeader::LinkParameterName parameterNameFromString(const String& name)
+{
+    if (equalIgnoringCase(name, "rel"))
+        return LinkHeader::LinkParameterRel;
+    if (equalIgnoringCase(name, "anchor"))
+        return LinkHeader::LinkParameterAnchor;
+    if (equalIgnoringCase(name, "crossorigin"))
+        return LinkHeader::LinkParameterCrossOrigin;
+    if (equalIgnoringCase(name, "title"))
+        return LinkHeader::LinkParameterTitle;
+    if (equalIgnoringCase(name, "media"))
+        return LinkHeader::LinkParameterMedia;
+    if (equalIgnoringCase(name, "type"))
+        return LinkHeader::LinkParameterType;
+    if (equalIgnoringCase(name, "rev"))
+        return LinkHeader::LinkParameterRev;
+    if (equalIgnoringCase(name, "hreflang"))
+        return LinkHeader::LinkParameterHreflang;
+    if (equalIgnoringCase(name, "as"))
+        return LinkHeader::LinkParameterAs;
+    return LinkHeader::LinkParameterUnknown;
+}
+
+void LinkHeader::setValue(LinkParameterName name, const String& value)
+{
+    if (name == LinkParameterRel && !m_rel)
+        m_rel = value.lower();
+    else if (name == LinkParameterAnchor)
+        m_isValid = false;
+    else if (name == LinkParameterCrossOrigin)
+        m_crossOrigin = value;
+    else if (name == LinkParameterAs)
+        m_as = value.lower();
+    else if (name == LinkParameterType)
+        m_mimeType = value.lower();
+    else if (name == LinkParameterMedia)
+        m_media = value.lower();
+}
+
+template <typename Iterator>
+LinkHeader::LinkHeader(Iterator begin, Iterator end)
+    : m_isValid(true)
+{
+    std::string url;
+    std::unordered_map<std::string, base::Optional<std::string>> params;
+    m_isValid = link_header_util::ParseLinkHeaderValue(begin, end, &url, &params);
+    if (!m_isValid)
+        return;
+
+    m_url = String(&url[0], url.length());
+    for (const auto& param : params) {
+        LinkParameterName name = parameterNameFromString(String(&param.first[0], param.first.length()));
+        if (!isExtensionParameter(name) && !param.second)
+            m_isValid = false;
+        std::string value = param.second.value_or("");
+        setValue(name, String(&value[0], value.length()));
+    }
+}
+
+LinkHeaderSet::LinkHeaderSet(const String& header)
+{
+    if (header.isNull())
+        return;
+
+    DCHECK(header.is8Bit()) << "Headers should always be 8 bit";
+    std::string headerString(reinterpret_cast<const char*>(header.characters8()), header.length());
+    for (const auto& value : link_header_util::SplitLinkHeader(headerString))
+        m_headerSet.append(LinkHeader(value.first, value.second));
+}
+
+} // namespace blink