WIP/proof-of-concept to make blink::LinkHeader reuse net:: parsing code

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 "net/http/http_util.h"
+#include "platform/ParsingUtilities.h"
+
+namespace blink {
+
+static LinkHeader::LinkParameterName paramterNameFromString(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, String value)
+{
+    // FIXME: Add support for more header parameters as neccessary.
+    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();
+}
+
+static bool extractURL(std::string::const_iterator begin, std::string::const_iterator end, std::string::const_iterator* urlBegin, std::string::const_iterator* urlEnd)
+{
+    if (begin == end)
+        return false;
+    if (*begin != '<')
+        return false;
+    ++begin;
+    *urlBegin = begin;
+    while (begin < end && *begin != '>')
+        ++begin;
+    *urlEnd = begin;
+    if (begin == end || *begin != '>')
+        return false;
+    return true;
+}
+
+LinkHeader::LinkHeader(std::string::const_iterator begin, std::string::const_iterator end)
+    : m_isValid(true)
+{
+    std::string::const_iterator urlBegin;
+    std::string::const_iterator urlEnd;
+    if (!extractURL(begin, end, &urlBegin, &urlEnd)) {
+        m_isValid = false;
+        return;
+    }
+    begin = urlEnd + 1;
+    net::HttpUtil::TrimLWS(&urlBegin, &urlEnd);
+    m_url = String(&urlBegin[0], urlEnd - urlBegin);
+
+    net::HttpUtil::TrimLWS(&begin, &end);
+    if (begin != end && *begin != ';') {
+        m_isValid = false;
+        return;
+    }
+    net::HttpUtil::NameValuePairsIterator params(begin, end, ';', net::HttpUtil::NameValuePairsIterator::VALUES_OPTIONAL);
+    while (params.GetNext()) {
+        const char* nameBegin = &*params.name_begin();
+        LinkParameterName name = paramterNameFromString(String(nameBegin, params.name_end() - params.name_begin()));
+        const char* valueBegin = &*params.value_begin();
+        setValue(name, String(valueBegin, params.value_end() - params.value_begin()));
+    }
+}
+
+LinkHeaderSet::LinkHeaderSet(const String& header)
+{
+    if (header.isNull())
+        return;
+
+    ASSERT(header.is8Bit());
+    std::string headerString(reinterpret_cast<const char*>(header.characters8()), header.length());
+    base::StringTokenizer tokenizer(headerString, ",");
+    tokenizer.set_paired_quote_chars("\"'<", "\"'>");
+    while (tokenizer.GetNext()) {
+        std::string::const_iterator valueBegin = tokenizer.token_begin();
+        std::string::const_iterator valueEnd = tokenizer.token_end();
+        net::HttpUtil::TrimLWS(&valueBegin, &valueEnd);
+        if (valueBegin != valueEnd)
+            m_headerSet.append(LinkHeader(valueBegin, valueEnd));
+    }
+}
+
+} // namespace blink