void MemoryCache::pruneDeadResourcesToSize(unsigned targetSize)
{
if (m_inPruneResources)
return;
TemporaryChange<bool> reentrancyProtector(m_inPruneResources, true);
if (targetSize && m_deadSize <= targetSize)
return;
bool canShrinkLRULists = true;
for (int i = m_allResources.size() - 1; i >= 0; i--) {
LRUList& list = *m_allResources[i];
// First flush all the decoded data in this queue.
// Remove from the head, since this is the least frequently accessed of the objects.
auto it = list.begin();
while (it != list.end()) {
CachedResource& current = **it;
// Increment the iterator now as the call to destroyDecodedData() below may
// invalidate the current iterator.
++it;
// Protect 'next' so it can't get deleted during destroyDecodedData().
CachedResourceHandle<CachedResource> next = it != list.end() ? *it : nullptr;
ASSERT(!next || next->inCache());
if (!current.hasClients() && !current.isPreloaded() && current.isLoaded()) {
// Destroy our decoded data. This will remove us from
// m_liveDecodedResources, and possibly move us to a different
// LRU list in m_allResources.
current.destroyDecodedData();
if (targetSize && m_deadSize <= targetSize)
return;
}
// Decoded data may reference other resources. Stop iterating if 'next' somehow got
// kicked out of cache during destroyDecodedData().
if (next && !next->inCache())
break;
}
// Now evict objects from this list.
// Remove from the head, since this is the least frequently accessed of the objects.
it = list.begin();
while (it != list.end()) {
CachedResource& current = **it;
// Increment the iterator now as the call to remove() below will
// invalidate the current iterator.
++it;
CachedResourceHandle<CachedResource> next = it != list.end() ? *it : nullptr;
ASSERT(!next || next->inCache());
if (!current.hasClients() && !current.isPreloaded() && !current.isCacheValidator()) {
remove(current);
if (targetSize && m_deadSize <= targetSize)
return;
}
if (next && !next->inCache())
break;
}
// Shrink the vector back down so we don't waste time inspecting
// empty LRU lists on future prunes.
if (!m_allResources[i]->isEmpty())
canShrinkLRULists = false;
else if (canShrinkLRULists)
m_allResources.shrink(i);
}
}
void MemoryCache::pruneDeadResourcesToSize(unsigned targetSize)
{
if (m_inPruneResources)
return;
TemporaryChange<bool> reentrancyProtector(m_inPruneResources, true);
int size = m_allResources.size();
// See if we have any purged resources we can evict.
for (int i = 0; i < size; i++) {
CachedResource* current = m_allResources[i].m_tail;
while (current) {
CachedResource* prev = current->m_prevInAllResourcesList;
if (current->wasPurged()) {
ASSERT(!current->hasClients());
ASSERT(!current->isPreloaded());
evict(current);
}
current = prev;
}
}
if (targetSize && m_deadSize <= targetSize)
return;
bool canShrinkLRULists = true;
for (int i = size - 1; i >= 0; i--) {
// Remove from the tail, since this is the least frequently accessed of the objects.
CachedResource* current = m_allResources[i].m_tail;
// First flush all the decoded data in this queue.
while (current) {
// Protect 'previous' so it can't get deleted during destroyDecodedData().
CachedResourceHandle<CachedResource> previous = current->m_prevInAllResourcesList;
ASSERT(!previous || previous->inCache());
if (!current->hasClients() && !current->isPreloaded() && current->isLoaded()) {
// Destroy our decoded data. This will remove us from
// m_liveDecodedResources, and possibly move us to a different
// LRU list in m_allResources.
current->destroyDecodedData();
if (targetSize && m_deadSize <= targetSize)
return;
}
// Decoded data may reference other resources. Stop iterating if 'previous' somehow got
// kicked out of cache during destroyDecodedData().
if (previous && !previous->inCache())
break;
current = previous.get();
}
// Now evict objects from this queue.
current = m_allResources[i].m_tail;
while (current) {
CachedResourceHandle<CachedResource> previous = current->m_prevInAllResourcesList;
ASSERT(!previous || previous->inCache());
if (!current->hasClients() && !current->isPreloaded() && !current->isCacheValidator()) {
if (!makeResourcePurgeable(current))
evict(current);
if (targetSize && m_deadSize <= targetSize)
return;
}
if (previous && !previous->inCache())
break;
current = previous.get();
}
// Shrink the vector back down so we don't waste time inspecting
// empty LRU lists on future prunes.
if (m_allResources[i].m_head)
canShrinkLRULists = false;
else if (canShrinkLRULists)
m_allResources.resize(i);
}
}
CachedResourceHandle<CachedResource> CachedResourceLoader::requestResource(CachedResource::Type type, CachedResourceRequest& request)
{
KURL url = request.resourceRequest().url();
LOG(ResourceLoading, "CachedResourceLoader::requestResource '%s', charset '%s', priority=%d, forPreload=%u", url.elidedString().latin1().data(), request.charset().latin1().data(), request.priority(), request.forPreload());
// If only the fragment identifiers differ, it is the same resource.
url = MemoryCache::removeFragmentIdentifierIfNeeded(url);
if (!url.isValid())
return 0;
if (!canRequest(type, url, request.forPreload()))
return 0;
if (Frame* f = frame())
f->loader()->client()->dispatchWillRequestResource(&request);
if (memoryCache()->disabled()) {
DocumentResourceMap::iterator it = m_documentResources.find(url.string());
if (it != m_documentResources.end()) {
it->value->setOwningCachedResourceLoader(0);
m_documentResources.remove(it);
}
}
// See if we can use an existing resource from the cache.
CachedResourceHandle<CachedResource> resource;
#if ENABLE(CACHE_PARTITIONING)
if (document())
request.mutableResourceRequest().setCachePartition(document()->topOrigin()->cachePartition());
#endif
resource = memoryCache()->resourceForRequest(request.resourceRequest());
const RevalidationPolicy policy = determineRevalidationPolicy(type, request.mutableResourceRequest(), request.forPreload(), resource.get(), request.defer());
switch (policy) {
case Reload:
memoryCache()->remove(resource.get());
// Fall through
case Load:
resource = loadResource(type, request, request.charset());
break;
case Revalidate:
resource = revalidateResource(request, resource.get());
break;
case Use:
memoryCache()->resourceAccessed(resource.get());
notifyLoadedFromMemoryCache(resource.get());
break;
}
if (!resource)
return 0;
if (!request.forPreload() || policy != Use)
resource->setLoadPriority(request.priority());
if ((policy != Use || resource->stillNeedsLoad()) && CachedResourceRequest::NoDefer == request.defer()) {
resource->load(this, request.options());
// We don't support immediate loads, but we do support immediate failure.
if (resource->errorOccurred()) {
if (resource->inCache())
memoryCache()->remove(resource.get());
return 0;
}
}
#if PLATFORM(CHROMIUM)
// FIXME: Temporarily leave main resource caching disabled for chromium, see https://bugs.webkit.org/show_bug.cgi?id=107962
// Ensure main resources aren't preloaded, and other main resource loads are removed from cache to prevent reuse.
if (type == CachedResource::MainResource) {
ASSERT(policy != Use);
ASSERT(policy != Revalidate);
memoryCache()->remove(resource.get());
if (request.forPreload())
return 0;
}
#endif
if (!request.resourceRequest().url().protocolIsData())
m_validatedURLs.add(request.resourceRequest().url());
ASSERT(resource->url() == url.string());
m_documentResources.set(resource->url(), resource);
return resource;
}