private static bool TrySetCacheControlValues(
CacheControlHeaderValue cc,
List <NameValueHeaderValue> nameValueList)
{
for (var i = 0; i < nameValueList.Count; i++)
{
var nameValue = nameValueList[i];
var name = nameValue.Name;
var success = true;
switch (name.Length)
{
case 6:
if (StringSegment.Equals(PublicString, name, StringComparison.OrdinalIgnoreCase))
{
success = TrySetTokenOnlyValue(nameValue, ref cc._public);
}
else
{
goto default;
}
break;
case 7:
if (StringSegment.Equals(MaxAgeString, name, StringComparison.OrdinalIgnoreCase))
{
success = TrySetTimeSpan(nameValue, ref cc._maxAge);
}
else if (StringSegment.Equals(PrivateString, name, StringComparison.OrdinalIgnoreCase))
{
success = TrySetOptionalTokenList(nameValue, ref cc._private, ref cc._privateHeaders);
}
else
{
goto default;
}
break;
case 8:
if (StringSegment.Equals(NoCacheString, name, StringComparison.OrdinalIgnoreCase))
{
success = TrySetOptionalTokenList(nameValue, ref cc._noCache, ref cc._noCacheHeaders);
}
else if (StringSegment.Equals(NoStoreString, name, StringComparison.OrdinalIgnoreCase))
{
success = TrySetTokenOnlyValue(nameValue, ref cc._noStore);
}
else if (StringSegment.Equals(SharedMaxAgeString, name, StringComparison.OrdinalIgnoreCase))
{
success = TrySetTimeSpan(nameValue, ref cc._sharedMaxAge);
}
else
{
goto default;
}
break;
case 9:
if (StringSegment.Equals(MaxStaleString, name, StringComparison.OrdinalIgnoreCase))
{
success = ((nameValue.Value == null) || TrySetTimeSpan(nameValue, ref cc._maxStaleLimit));
if (success)
{
cc._maxStale = true;
}
}
else if (StringSegment.Equals(MinFreshString, name, StringComparison.OrdinalIgnoreCase))
{
success = TrySetTimeSpan(nameValue, ref cc._minFresh);
}
else
{
goto default;
}
break;
case 12:
if (StringSegment.Equals(NoTransformString, name, StringComparison.OrdinalIgnoreCase))
{
success = TrySetTokenOnlyValue(nameValue, ref cc._noTransform);
}
else
{
goto default;
}
break;
case 14:
if (StringSegment.Equals(OnlyIfCachedString, name, StringComparison.OrdinalIgnoreCase))
{
success = TrySetTokenOnlyValue(nameValue, ref cc._onlyIfCached);
}
else
{
goto default;
}
break;
case 15:
if (StringSegment.Equals(MustRevalidateString, name, StringComparison.OrdinalIgnoreCase))
{
success = TrySetTokenOnlyValue(nameValue, ref cc._mustRevalidate);
}
else
{
goto default;
}
break;
case 16:
if (StringSegment.Equals(ProxyRevalidateString, name, StringComparison.OrdinalIgnoreCase))
{
success = TrySetTokenOnlyValue(nameValue, ref cc._proxyRevalidate);
}
else
{
goto default;
}
break;
default:
cc.Extensions.Add(nameValue); // success is always true
break;
}
if (!success)
{
return(false);
}
}
return(true);
}
private static int GetCacheControlLength(StringSegment input, int startIndex, out CacheControlHeaderValue parsedValue)
{
Contract.Requires(startIndex >= 0);
parsedValue = null;
if (StringSegment.IsNullOrEmpty(input) || (startIndex >= input.Length))
{
return(0);
}
// Cache-Control header consists of a list of name/value pairs, where the value is optional. So use an
// instance of NameValueHeaderParser to parse the string.
var current = startIndex;
NameValueHeaderValue nameValue = null;
var nameValueList = new List <NameValueHeaderValue>();
while (current < input.Length)
{
if (!NameValueHeaderValue.MultipleValueParser.TryParseValue(input, ref current, out nameValue))
{
return(0);
}
nameValueList.Add(nameValue);
}
// If we get here, we were able to successfully parse the string as list of name/value pairs. Now analyze
// the name/value pairs.
// Cache-Control is a header supporting lists of values. However, expose the header as an instance of
// CacheControlHeaderValue.
var result = new CacheControlHeaderValue();
if (!TrySetCacheControlValues(result, nameValueList))
{
return(0);
}
parsedValue = result;
// If we get here we successfully parsed the whole string.
return(input.Length - startIndex);
}