static bool canUseResponse(ResourceResponse& response, double responseTimestamp)
{
if (response.isNull())
return false;
// FIXME: Why isn't must-revalidate considered a reason we can't use the response?
if (response.cacheControlContainsNoCache() || response.cacheControlContainsNoStore())
return false;
if (response.httpStatusCode() == 303) {
// Must not be cached.
return false;
}
if (response.httpStatusCode() == 302 || response.httpStatusCode() == 307) {
// Default to not cacheable unless explicitly allowed.
bool hasMaxAge = std::isfinite(response.cacheControlMaxAge());
bool hasExpires = std::isfinite(response.expires());
// TODO: consider catching Cache-Control "private" and "public" here.
if (!hasMaxAge && !hasExpires)
return false;
}
return currentAge(response, responseTimestamp) <= freshnessLifetime(response, responseTimestamp);
}
static bool canUseResponse(ResourceResponse& response, double responseTimestamp)
{
if (response.isNull())
return false;
// FIXME: Why isn't must-revalidate considered a reason we can't use the response?
if (response.cacheControlContainsNoCache() || response.cacheControlContainsNoStore())
return false;
if (response.httpStatusCode() == 303) {
// Must not be cached.
return false;
}
if (response.httpStatusCode() == 302 || response.httpStatusCode() == 307) {
// Default to not cacheable.
// FIXME: Consider allowing these to be cached if they have headers permitting caching.
return false;
}
return currentAge(response, responseTimestamp) <= freshnessLifetime(response, responseTimestamp);
}
bool CurlCacheEntry::parseResponseHeaders(ResourceResponse& response)
{
double fileTime;
time_t fileModificationDate;
if (getFileModificationTime(m_headerFilename, fileModificationDate)) {
fileTime = difftime(fileModificationDate, 0);
fileTime *= 1000.0;
} else
fileTime = currentTimeMS(); // GMT
if (response.cacheControlContainsNoCache() || response.cacheControlContainsNoStore())
return false;
double maxAge = 0;
bool maxAgeIsValid = false;
if (response.cacheControlContainsMustRevalidate())
maxAge = 0;
else {
maxAge = response.cacheControlMaxAge();
if (std::isnan(maxAge))
maxAge = 0;
else
maxAgeIsValid = true;
}
if (!response.hasCacheValidatorFields())
return false;
double lastModificationDate = 0;
double responseDate = 0;
double expirationDate = 0;
lastModificationDate = response.lastModified();
if (std::isnan(lastModificationDate))
lastModificationDate = 0;
responseDate = response.date();
if (std::isnan(responseDate))
responseDate = 0;
expirationDate = response.expires();
if (std::isnan(expirationDate))
expirationDate = 0;
if (maxAgeIsValid) {
// when both the cache entry and the response contain max-age, the lesser one takes priority
double expires = fileTime + maxAge * 1000;
if (m_expireDate == -1 || m_expireDate > expires)
m_expireDate = expires;
} else if (responseDate > 0 && expirationDate >= responseDate)
m_expireDate = fileTime + (expirationDate - responseDate);
// if there were no lifetime information
if (m_expireDate == -1) {
if (lastModificationDate > 0)
m_expireDate = fileTime + (fileTime - lastModificationDate) * 0.1;
else
m_expireDate = 0;
}
String etag = response.httpHeaderField("ETag");
if (!etag.isNull())
m_requestHeaders.set("If-None-Match", etag);
String lastModified = response.httpHeaderField("Last-Modified");
if (!lastModified.isNull())
m_requestHeaders.set("If-Modified-Since", lastModified);
if (etag.isNull() && lastModified.isNull())
return false;
m_headerInMemory = true;
return true;
}
