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

third_party/WebKit/Source/core/loader/LinkHeader.cpp

Index: third_party/WebKit/Source/core/loader/LinkHeader.cpp
diff --git a/third_party/WebKit/Source/core/loader/LinkHeader.cpp b/third_party/WebKit/Source/core/loader/LinkHeader.cpp
deleted file mode 100644
index f2877e43ebabf72e491e1108feb6fcaa7d6073be..0000000000000000000000000000000000000000
--- a/third_party/WebKit/Source/core/loader/LinkHeader.cpp
+++ /dev/null
@@ -1,323 +0,0 @@
-// 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 "core/loader/LinkHeader.h"
-
-#include "platform/ParsingUtilities.h"
-
-namespace blink {
-
-// LWSP definition in https://www.ietf.org/rfc/rfc0822.txt
-template <typename CharType>
-static bool isWhitespace(CharType chr)
-{
-    return (chr == ' ') || (chr == '\t');
-}
-
-template <typename CharType>
-static bool isValidURLChar(CharType chr)
-{
-    return !isWhitespace(chr) && chr != '>';
-}
-
-template <typename CharType>
-static bool isValidParameterNameChar(CharType chr)
-{
-    // TODO(yoav): We need to move this function to a central location and possibly rewrite as a lookup table. https://crbug.com/527324
-
-    // Alpha-numeric is a valid char.
-    // This is likely the common case - bailing early.
-    if (isASCIIAlphanumeric(chr))
-        return true;
-    // A separator or CTL or '%', '*' or '\'' means the char is not valid.
-    // So any of: |{}[]/\:;<=>?@,()*'"%
-    if (chr <= ' ' || chr > '|' || chr == '{' || chr == ']' || chr == '['
-        || chr == '/' || chr == '\\' || (chr <= '@' && chr >= ':') || chr == ','
-        || (chr >= '(' && chr <= '*') || chr == '\'' || chr == '"' || chr == '%') {
-        return false;
-    }
-    return true;
-}
-
-template <typename CharType>
-static bool isValidParameterValueEnd(CharType chr)
-{
-    return chr == ';' || chr == ',';
-}
-
-template <typename CharType>
-static bool isValidParameterValueChar(CharType chr)
-{
-    return !isWhitespace(chr) && !isValidParameterValueEnd(chr);
-}
-
-// 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;
-}
-
-// Before:
-//
-// <cat.jpg>; rel=preload
-// ^                     ^
-// position              end
-//
-// After (if successful: otherwise the method returns false)
-//
-// <cat.jpg>; rel=preload
-//          ^            ^
-//          position     end
-template <typename CharType>
-static bool parseURL(CharType*& position, CharType* end, String& url)
-{
-    skipWhile<CharType, isWhitespace>(position, end);
-    if (!skipExactly<CharType>(position, end, '<'))
-        return false;
-    skipWhile<CharType, isWhitespace>(position, end);
-
-    CharType* urlStart = position;
-    skipWhile<CharType, isValidURLChar>(position, end);
-    CharType* urlEnd = position;
-    skipUntil<CharType>(position, end, '>');
-    if (!skipExactly<CharType>(position, end, '>'))
-        return false;
-
-    url = String(urlStart, urlEnd - urlStart);
-    return true;
-}
-
-template <typename CharType>
-static bool invalidParameterDelimiter(CharType*& position, CharType* end)
-{
-    return (!skipExactly<CharType>(position, end, ';') && (position < end) && (*position != ','));
-}
-
-template <typename CharType>
-static bool validFieldEnd(CharType*& position, CharType* end)
-{
-    ASSERT(position <= end);
-    return (position == end || *position == ',');
-}
-
-// Before:
-//
-// <cat.jpg>; rel=preload
-//          ^            ^
-//          position     end
-//
-// After (if successful: otherwise the method returns false, and modifies the isValid boolean accordingly)
-//
-// <cat.jpg>; rel=preload
-//            ^          ^
-//            position  end
-template <typename CharType>
-static bool parseParameterDelimiter(CharType*& position, CharType* end, bool& isValid)
-{
-    isValid = true;
-    skipWhile<CharType, isWhitespace>(position, end);
-    if (invalidParameterDelimiter(position, end)) {
-        isValid = false;
-        return false;
-    }
-    skipWhile<CharType, isWhitespace>(position, end);
-    if (validFieldEnd(position, end))
-        return false;
-    return true;
-}
-
-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;
-}
-
-// Before:
-//
-// <cat.jpg>; rel=preload
-//            ^          ^
-//            position   end
-//
-// After (if successful: otherwise the method returns false)
-//
-// <cat.jpg>; rel=preload
-//                ^      ^
-//            position  end
-template <typename CharType>
-static bool parseParameterName(CharType*& position, CharType* end, LinkHeader::LinkParameterName& name)
-{
-    CharType* nameStart = position;
-    skipWhile<CharType, isValidParameterNameChar>(position, end);
-    CharType* nameEnd = position;
-    skipWhile<CharType, isWhitespace>(position, end);
-    bool hasEqual = skipExactly<CharType>(position, end, '=');
-    skipWhile<CharType, isWhitespace>(position, end);
-    name = paramterNameFromString(String(nameStart, nameEnd - nameStart));
-    if (hasEqual)
-        return true;
-    bool validParameterValueEnd = (position == end) || isValidParameterValueEnd(*position);
-    return validParameterValueEnd && isExtensionParameter(name);
-}
-
-// Before:
-//
-// <cat.jpg>; rel="preload"; type="image/jpeg";
-//                ^                            ^
-//            position                        end
-//
-// After (if the parameter starts with a quote, otherwise the method returns false)
-//
-// <cat.jpg>; rel="preload"; type="image/jpeg";
-//                         ^                   ^
-//                     position               end
-template <typename CharType>
-static bool skipQuotesIfNeeded(CharType*& position, CharType* end, bool& completeQuotes)
-{
-    ASSERT(position <= end);
-    unsigned char quote;
-    completeQuotes = false;
-    if (skipExactly<CharType>(position, end, '\''))
-        quote = '\'';
-    else if (skipExactly<CharType>(position, end, '"'))
-        quote = '"';
-    else
-        return false;
-
-    while (!completeQuotes && position < end) {
-        skipUntil(position, end, static_cast<CharType>(quote));
-        if (*(position - 1) != '\\')
-            completeQuotes = true;
-        completeQuotes = skipExactly(position, end, static_cast<CharType>(quote)) && completeQuotes;
-    }
-    return true;
-}
-
-// Before:
-//
-// <cat.jpg>; rel=preload; foo=bar
-//                ^               ^
-//            position            end
-//
-// After (if successful: otherwise the method returns false)
-//
-// <cat.jpg>; rel=preload; foo=bar
-//                       ^        ^
-//                   position     end
-template <typename CharType>
-static bool parseParameterValue(CharType*& position, CharType* end, String& value)
-{
-    CharType* valueStart = position;
-    CharType* valueEnd = position;
-    bool completeQuotes;
-    bool hasQuotes = skipQuotesIfNeeded(position, end, completeQuotes);
-    if (!hasQuotes) {
-        skipWhile<CharType, isValidParameterValueChar>(position, end);
-    }
-    valueEnd = position;
-    skipWhile<CharType, isWhitespace>(position, end);
-    if ((!completeQuotes && valueStart == valueEnd) || (position != end && !isValidParameterValueEnd(*position))) {
-        value = String("");
-        return false;
-    }
-    if (hasQuotes)
-        ++valueStart;
-    if (completeQuotes)
-        --valueEnd;
-    value = String(valueStart, valueEnd - valueStart);
-    return !hasQuotes || completeQuotes;
-}
-
-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 = crossOriginAttributeValue(value);
-    else if (name == LinkParameterAs)
-        m_as = value.lower();
-}
-
-template <typename CharType>
-static void findNextHeader(CharType*& position, CharType* end)
-{
-    skipUntil<CharType>(position, end, ',');
-    skipExactly<CharType>(position, end, ',');
-}
-
-template <typename CharType>
-LinkHeader::LinkHeader(CharType*& position, CharType* end)
-    : m_crossOrigin(CrossOriginAttributeNotSet)
-    , m_isValid(true)
-{
-    if (!parseURL(position, end, m_url)) {
-        m_isValid = false;
-        findNextHeader(position, end);
-        return;
-    }
-
-    while (m_isValid && position < end) {
-        if (!parseParameterDelimiter(position, end, m_isValid)) {
-            findNextHeader(position, end);
-            return;
-        }
-
-        LinkParameterName parameterName;
-        if (!parseParameterName(position, end, parameterName)) {
-            findNextHeader(position, end);
-            m_isValid = false;
-            return;
-        }
-
-        String parameterValue;
-        if (!parseParameterValue(position, end, parameterValue) && !isExtensionParameter(parameterName)) {
-            findNextHeader(position, end);
-            m_isValid = false;
-            return;
-        }
-
-        setValue(parameterName, parameterValue);
-    }
-}
-
-LinkHeaderSet::LinkHeaderSet(const String& header)
-{
-    if (header.isNull())
-        return;
-
-    if (header.is8Bit())
-        init(header.characters8(), header.length());
-    else
-        init(header.characters16(), header.length());
-}
-
-template <typename CharType>
-void LinkHeaderSet::init(CharType* headerValue, unsigned len)
-{
-    CharType* position = headerValue;
-    CharType* end = headerValue + len;
-    while (position < end)
-        m_headerSet.append(LinkHeader(position, end));
-}
-
-} // namespace blink