WebCore/loader/Cache.cpp
changeset 0 4f2f89ce4247
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/WebCore/loader/Cache.cpp	Fri Sep 17 09:02:29 2010 +0300
@@ -0,0 +1,754 @@
+/*
+    Copyright (C) 1998 Lars Knoll (knoll@mpi-hd.mpg.de)
+    Copyright (C) 2001 Dirk Mueller (mueller@kde.org)
+    Copyright (C) 2002 Waldo Bastian (bastian@kde.org)
+    Copyright (C) 2004, 2005, 2006, 2007, 2008 Apple Inc. All rights reserved.
+
+    This library is free software; you can redistribute it and/or
+    modify it under the terms of the GNU Library General Public
+    License as published by the Free Software Foundation; either
+    version 2 of the License, or (at your option) any later version.
+
+    This library is distributed in the hope that it will be useful,
+    but WITHOUT ANY WARRANTY; without even the implied warranty of
+    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+    Library General Public License for more details.
+
+    You should have received a copy of the GNU Library General Public License
+    along with this library; see the file COPYING.LIB.  If not, write to
+    the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
+    Boston, MA 02110-1301, USA.
+*/
+
+#include "config.h"
+#include "Cache.h"
+
+#include "CachedCSSStyleSheet.h"
+#include "CachedFont.h"
+#include "CachedImage.h"
+#include "CachedScript.h"
+#include "CachedXSLStyleSheet.h"
+#include "DocLoader.h"
+#include "Document.h"
+#include "FrameLoader.h"
+#include "FrameLoaderTypes.h"
+#include "FrameView.h"
+#include "Image.h"
+#include "ResourceHandle.h"
+#include "SecurityOrigin.h"
+#include <stdio.h>
+#include <wtf/CurrentTime.h>
+
+using namespace std;
+
+namespace WebCore {
+
+static const int cDefaultCacheCapacity = 8192 * 1024;
+static const double cMinDelayBeforeLiveDecodedPrune = 1; // Seconds.
+static const float cTargetPrunePercentage = .95f; // Percentage of capacity toward which we prune, to avoid immediately pruning again.
+static const double cDefaultDecodedDataDeletionInterval = 0;
+
+Cache* cache()
+{
+    static Cache* staticCache = new Cache;
+    return staticCache;
+}
+
+Cache::Cache()
+    : m_disabled(false)
+    , m_pruneEnabled(true)
+    , m_inPruneDeadResources(false)
+    , m_capacity(cDefaultCacheCapacity)
+    , m_minDeadCapacity(0)
+    , m_maxDeadCapacity(cDefaultCacheCapacity)
+    , m_deadDecodedDataDeletionInterval(cDefaultDecodedDataDeletionInterval)
+    , m_liveSize(0)
+    , m_deadSize(0)
+{
+}
+
+static CachedResource* createResource(CachedResource::Type type, const KURL& url, const String& charset)
+{
+    switch (type) {
+    case CachedResource::ImageResource:
+        return new CachedImage(url.string());
+    case CachedResource::CSSStyleSheet:
+        return new CachedCSSStyleSheet(url.string(), charset);
+    case CachedResource::Script:
+        return new CachedScript(url.string(), charset);
+    case CachedResource::FontResource:
+        return new CachedFont(url.string());
+#if ENABLE(XSLT)
+    case CachedResource::XSLStyleSheet:
+        return new CachedXSLStyleSheet(url.string());
+#endif
+#if ENABLE(XBL)
+    case CachedResource::XBLStyleSheet:
+        return new CachedXBLDocument(url.string());
+#endif
+#if ENABLE(LINK_PREFETCH)
+    case CachedResource::LinkPrefetch:
+        return new CachedResource(url.string(), CachedResource::LinkPrefetch);
+#endif
+    default:
+        break;
+    }
+
+    return 0;
+}
+
+CachedResource* Cache::requestResource(DocLoader* docLoader, CachedResource::Type type, const KURL& url, const String& charset, bool requestIsPreload)
+{
+    // FIXME: Do we really need to special-case an empty URL?
+    // Would it be better to just go on with the cache code and let it fail later?
+    if (url.isEmpty())
+        return 0;
+    
+    // Look up the resource in our map.
+    CachedResource* resource = resourceForURL(url.string());
+    
+    if (resource && requestIsPreload && !resource->isPreloaded())
+        return 0;
+    
+    if (SecurityOrigin::restrictAccessToLocal() && !SecurityOrigin::canLoad(url, String(), docLoader->doc())) {
+        Document* doc = docLoader->doc();
+        if (doc && !requestIsPreload)
+            FrameLoader::reportLocalLoadFailed(doc->frame(), url.string());
+        return 0;
+    }
+    
+    if (!resource) {
+        // The resource does not exist. Create it.
+        resource = createResource(type, url, charset);
+        ASSERT(resource);
+
+        // Pretend the resource is in the cache, to prevent it from being deleted during the load() call.
+        // FIXME: CachedResource should just use normal refcounting instead.
+        resource->setInCache(true);
+        
+        resource->load(docLoader);
+        
+        if (resource->errorOccurred()) {
+            // We don't support immediate loads, but we do support immediate failure.
+            // In that case we should to delete the resource now and return 0 because otherwise
+            // it would leak if no ref/deref was ever done on it.
+            resource->setInCache(false);
+            delete resource;
+            return 0;
+        }
+
+        if (!disabled())
+            m_resources.set(url.string(), resource);  // The size will be added in later once the resource is loaded and calls back to us with the new size.
+        else {
+            // Kick the resource out of the cache, because the cache is disabled.
+            resource->setInCache(false);
+            resource->setDocLoader(docLoader);
+        }
+    }
+
+    if (resource->type() != type)
+        return 0;
+
+    if (!disabled()) {
+        // This will move the resource to the front of its LRU list and increase its access count.
+        resourceAccessed(resource);
+    }
+
+    return resource;
+}
+    
+CachedCSSStyleSheet* Cache::requestUserCSSStyleSheet(DocLoader* docLoader, const String& url, const String& charset)
+{
+    CachedCSSStyleSheet* userSheet;
+    if (CachedResource* existing = resourceForURL(url)) {
+        if (existing->type() != CachedResource::CSSStyleSheet)
+            return 0;
+        userSheet = static_cast<CachedCSSStyleSheet*>(existing);
+    } else {
+        userSheet = new CachedCSSStyleSheet(url, charset);
+
+        // Pretend the resource is in the cache, to prevent it from being deleted during the load() call.
+        // FIXME: CachedResource should just use normal refcounting instead.
+        userSheet->setInCache(true);
+        // Don't load incrementally, skip load checks, don't send resource load callbacks.
+        userSheet->load(docLoader, false, SkipSecurityCheck, false);
+        if (!disabled())
+            m_resources.set(url, userSheet);
+        else
+            userSheet->setInCache(false);
+    }
+
+    if (!disabled()) {
+        // This will move the resource to the front of its LRU list and increase its access count.
+        resourceAccessed(userSheet);
+    }
+
+    return userSheet;
+}
+    
+void Cache::revalidateResource(CachedResource* resource, DocLoader* docLoader)
+{
+    ASSERT(resource);
+    ASSERT(resource->inCache());
+    ASSERT(resource == m_resources.get(resource->url()));
+    ASSERT(!disabled());
+    if (resource->resourceToRevalidate())
+        return;
+    if (!resource->canUseCacheValidator()) {
+        evict(resource);
+        return;
+    }
+    const String& url = resource->url();
+    CachedResource* newResource = createResource(resource->type(), KURL(ParsedURLString, url), resource->encoding());
+    newResource->setResourceToRevalidate(resource);
+    evict(resource);
+    m_resources.set(url, newResource);
+    newResource->setInCache(true);
+    resourceAccessed(newResource);
+    newResource->load(docLoader);
+}
+    
+void Cache::revalidationSucceeded(CachedResource* revalidatingResource, const ResourceResponse& response)
+{
+    CachedResource* resource = revalidatingResource->resourceToRevalidate();
+    ASSERT(resource);
+    ASSERT(!resource->inCache());
+    ASSERT(resource->isLoaded());
+    ASSERT(revalidatingResource->inCache());
+    
+    evict(revalidatingResource);
+
+    ASSERT(!m_resources.get(resource->url()));
+    m_resources.set(resource->url(), resource);
+    resource->setInCache(true);
+    resource->updateResponseAfterRevalidation(response);
+    insertInLRUList(resource);
+    int delta = resource->size();
+    if (resource->decodedSize() && resource->hasClients())
+        insertInLiveDecodedResourcesList(resource);
+    if (delta)
+        adjustSize(resource->hasClients(), delta);
+    
+    revalidatingResource->switchClientsToRevalidatedResource();
+    // this deletes the revalidating resource
+    revalidatingResource->clearResourceToRevalidate();
+}
+
+void Cache::revalidationFailed(CachedResource* revalidatingResource)
+{
+    ASSERT(revalidatingResource->resourceToRevalidate());
+    revalidatingResource->clearResourceToRevalidate();
+}
+
+CachedResource* Cache::resourceForURL(const String& url)
+{
+    CachedResource* resource = m_resources.get(url);
+    if (resource && !resource->makePurgeable(false)) {
+        ASSERT(!resource->hasClients());
+        evict(resource);
+        return 0;
+    }
+    return resource;
+}
+
+unsigned Cache::deadCapacity() const 
+{
+    // Dead resource capacity is whatever space is not occupied by live resources, bounded by an independent minimum and maximum.
+    unsigned capacity = m_capacity - min(m_liveSize, m_capacity); // Start with available capacity.
+    capacity = max(capacity, m_minDeadCapacity); // Make sure it's above the minimum.
+    capacity = min(capacity, m_maxDeadCapacity); // Make sure it's below the maximum.
+    return capacity;
+}
+
+unsigned Cache::liveCapacity() const 
+{ 
+    // Live resource capacity is whatever is left over after calculating dead resource capacity.
+    return m_capacity - deadCapacity();
+}
+
+void Cache::pruneLiveResources()
+{
+    if (!m_pruneEnabled)
+        return;
+
+    unsigned capacity = liveCapacity();
+    if (capacity && m_liveSize <= capacity)
+        return;
+
+    unsigned targetSize = static_cast<unsigned>(capacity * cTargetPrunePercentage); // Cut by a percentage to avoid immediately pruning again.
+    double currentTime = FrameView::currentPaintTimeStamp();
+    if (!currentTime) // In case prune is called directly, outside of a Frame paint.
+        currentTime = WTF::currentTime();
+    
+    // Destroy any decoded data in live objects that we can.
+    // Start from the tail, since this is the least recently accessed of the objects.
+
+    // The list might not be sorted by the m_lastDecodedAccessTime. The impact
+    // of this weaker invariant is minor as the below if statement to check the
+    // elapsedTime will evaluate to false as the currentTime will be a lot
+    // greater than the current->m_lastDecodedAccessTime.
+    // For more details see: https://bugs.webkit.org/show_bug.cgi?id=30209
+    CachedResource* current = m_liveDecodedResources.m_tail;
+    while (current) {
+        CachedResource* prev = current->m_prevInLiveResourcesList;
+        ASSERT(current->hasClients());
+        if (current->isLoaded() && current->decodedSize()) {
+            // Check to see if the remaining resources are too new to prune.
+            double elapsedTime = currentTime - current->m_lastDecodedAccessTime;
+            if (elapsedTime < cMinDelayBeforeLiveDecodedPrune)
+                return;
+
+            // 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_liveSize <= targetSize)
+                return;
+        }
+        current = prev;
+    }
+}
+
+void Cache::pruneDeadResources()
+{
+    if (!m_pruneEnabled)
+        return;
+
+    unsigned capacity = deadCapacity();
+    if (capacity && m_deadSize <= capacity)
+        return;
+
+    unsigned targetSize = static_cast<unsigned>(capacity * cTargetPrunePercentage); // Cut by a percentage to avoid immediately pruning again.
+    int size = m_allResources.size();
+    
+    if (!m_inPruneDeadResources) {
+        // 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;
+    m_inPruneDeadResources = 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) {
+            CachedResource* prev = current->m_prevInAllResourcesList;
+            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) {
+                    m_inPruneDeadResources = false;
+                    return;
+                }
+            }
+            current = prev;
+        }
+
+        // Now evict objects from this queue.
+        current = m_allResources[i].m_tail;
+        while (current) {
+            CachedResource* prev = current->m_prevInAllResourcesList;
+            if (!current->hasClients() && !current->isPreloaded() && !current->isCacheValidator()) {
+                evict(current);
+                // If evict() caused pruneDeadResources() to be re-entered, bail out. This can happen when removing an
+                // SVG CachedImage that has subresources.
+                if (!m_inPruneDeadResources)
+                    return;
+
+                if (targetSize && m_deadSize <= targetSize) {
+                    m_inPruneDeadResources = false;
+                    return;
+                }
+            }
+            current = prev;
+        }
+            
+        // 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);
+    }
+    m_inPruneDeadResources = false;
+}
+
+void Cache::setCapacities(unsigned minDeadBytes, unsigned maxDeadBytes, unsigned totalBytes)
+{
+    ASSERT(minDeadBytes <= maxDeadBytes);
+    ASSERT(maxDeadBytes <= totalBytes);
+    m_minDeadCapacity = minDeadBytes;
+    m_maxDeadCapacity = maxDeadBytes;
+    m_capacity = totalBytes;
+    prune();
+}
+
+void Cache::evict(CachedResource* resource)
+{
+    // The resource may have already been removed by someone other than our caller,
+    // who needed a fresh copy for a reload. See <http://bugs.webkit.org/show_bug.cgi?id=12479#c6>.
+    if (resource->inCache()) {
+        // Remove from the resource map.
+        m_resources.remove(resource->url());
+        resource->setInCache(false);
+
+        // Remove from the appropriate LRU list.
+        removeFromLRUList(resource);
+        removeFromLiveDecodedResourcesList(resource);
+
+        // Subtract from our size totals.
+        int delta = -static_cast<int>(resource->size());
+        if (delta)
+            adjustSize(resource->hasClients(), delta);
+    } else
+        ASSERT(m_resources.get(resource->url()) != resource);
+
+    if (resource->canDelete())
+        delete resource;
+}
+
+void Cache::addDocLoader(DocLoader* docLoader)
+{
+    m_docLoaders.add(docLoader);
+}
+
+void Cache::removeDocLoader(DocLoader* docLoader)
+{
+    m_docLoaders.remove(docLoader);
+}
+
+static inline unsigned fastLog2(unsigned i)
+{
+    unsigned log2 = 0;
+    if (i & (i - 1))
+        log2 += 1;
+    if (i >> 16)
+        log2 += 16, i >>= 16;
+    if (i >> 8)
+        log2 += 8, i >>= 8;
+    if (i >> 4)
+        log2 += 4, i >>= 4;
+    if (i >> 2)
+        log2 += 2, i >>= 2;
+    if (i >> 1)
+        log2 += 1;
+    return log2;
+}
+
+Cache::LRUList* Cache::lruListFor(CachedResource* resource)
+{
+    unsigned accessCount = max(resource->accessCount(), 1U);
+    unsigned queueIndex = fastLog2(resource->size() / accessCount);
+#ifndef NDEBUG
+    resource->m_lruIndex = queueIndex;
+#endif
+    if (m_allResources.size() <= queueIndex)
+        m_allResources.grow(queueIndex + 1);
+    return &m_allResources[queueIndex];
+}
+
+void Cache::removeFromLRUList(CachedResource* resource)
+{
+    // If we've never been accessed, then we're brand new and not in any list.
+    if (resource->accessCount() == 0)
+        return;
+
+#if !ASSERT_DISABLED
+    unsigned oldListIndex = resource->m_lruIndex;
+#endif
+
+    LRUList* list = lruListFor(resource);
+
+#if !ASSERT_DISABLED
+    // Verify that the list we got is the list we want.
+    ASSERT(resource->m_lruIndex == oldListIndex);
+
+    // Verify that we are in fact in this list.
+    bool found = false;
+    for (CachedResource* current = list->m_head; current; current = current->m_nextInAllResourcesList) {
+        if (current == resource) {
+            found = true;
+            break;
+        }
+    }
+    ASSERT(found);
+#endif
+
+    CachedResource* next = resource->m_nextInAllResourcesList;
+    CachedResource* prev = resource->m_prevInAllResourcesList;
+    
+    if (next == 0 && prev == 0 && list->m_head != resource)
+        return;
+    
+    resource->m_nextInAllResourcesList = 0;
+    resource->m_prevInAllResourcesList = 0;
+    
+    if (next)
+        next->m_prevInAllResourcesList = prev;
+    else if (list->m_tail == resource)
+        list->m_tail = prev;
+
+    if (prev)
+        prev->m_nextInAllResourcesList = next;
+    else if (list->m_head == resource)
+        list->m_head = next;
+}
+
+void Cache::insertInLRUList(CachedResource* resource)
+{
+    // Make sure we aren't in some list already.
+    ASSERT(!resource->m_nextInAllResourcesList && !resource->m_prevInAllResourcesList);
+    ASSERT(resource->inCache());
+    ASSERT(resource->accessCount() > 0);
+    
+    LRUList* list = lruListFor(resource);
+
+    resource->m_nextInAllResourcesList = list->m_head;
+    if (list->m_head)
+        list->m_head->m_prevInAllResourcesList = resource;
+    list->m_head = resource;
+    
+    if (!resource->m_nextInAllResourcesList)
+        list->m_tail = resource;
+        
+#ifndef NDEBUG
+    // Verify that we are in now in the list like we should be.
+    list = lruListFor(resource);
+    bool found = false;
+    for (CachedResource* current = list->m_head; current; current = current->m_nextInAllResourcesList) {
+        if (current == resource) {
+            found = true;
+            break;
+        }
+    }
+    ASSERT(found);
+#endif
+
+}
+
+void Cache::resourceAccessed(CachedResource* resource)
+{
+    ASSERT(resource->inCache());
+    
+    // Need to make sure to remove before we increase the access count, since
+    // the queue will possibly change.
+    removeFromLRUList(resource);
+    
+    // If this is the first time the resource has been accessed, adjust the size of the cache to account for its initial size.
+    if (!resource->accessCount())
+        adjustSize(resource->hasClients(), resource->size());
+    
+    // Add to our access count.
+    resource->increaseAccessCount();
+    
+    // Now insert into the new queue.
+    insertInLRUList(resource);
+}
+
+void Cache::removeFromLiveDecodedResourcesList(CachedResource* resource)
+{
+    // If we've never been accessed, then we're brand new and not in any list.
+    if (!resource->m_inLiveDecodedResourcesList)
+        return;
+    resource->m_inLiveDecodedResourcesList = false;
+
+#ifndef NDEBUG
+    // Verify that we are in fact in this list.
+    bool found = false;
+    for (CachedResource* current = m_liveDecodedResources.m_head; current; current = current->m_nextInLiveResourcesList) {
+        if (current == resource) {
+            found = true;
+            break;
+        }
+    }
+    ASSERT(found);
+#endif
+
+    CachedResource* next = resource->m_nextInLiveResourcesList;
+    CachedResource* prev = resource->m_prevInLiveResourcesList;
+    
+    if (next == 0 && prev == 0 && m_liveDecodedResources.m_head != resource)
+        return;
+    
+    resource->m_nextInLiveResourcesList = 0;
+    resource->m_prevInLiveResourcesList = 0;
+    
+    if (next)
+        next->m_prevInLiveResourcesList = prev;
+    else if (m_liveDecodedResources.m_tail == resource)
+        m_liveDecodedResources.m_tail = prev;
+
+    if (prev)
+        prev->m_nextInLiveResourcesList = next;
+    else if (m_liveDecodedResources.m_head == resource)
+        m_liveDecodedResources.m_head = next;
+}
+
+void Cache::insertInLiveDecodedResourcesList(CachedResource* resource)
+{
+    // Make sure we aren't in the list already.
+    ASSERT(!resource->m_nextInLiveResourcesList && !resource->m_prevInLiveResourcesList && !resource->m_inLiveDecodedResourcesList);
+    resource->m_inLiveDecodedResourcesList = true;
+
+    resource->m_nextInLiveResourcesList = m_liveDecodedResources.m_head;
+    if (m_liveDecodedResources.m_head)
+        m_liveDecodedResources.m_head->m_prevInLiveResourcesList = resource;
+    m_liveDecodedResources.m_head = resource;
+    
+    if (!resource->m_nextInLiveResourcesList)
+        m_liveDecodedResources.m_tail = resource;
+        
+#ifndef NDEBUG
+    // Verify that we are in now in the list like we should be.
+    bool found = false;
+    for (CachedResource* current = m_liveDecodedResources.m_head; current; current = current->m_nextInLiveResourcesList) {
+        if (current == resource) {
+            found = true;
+            break;
+        }
+    }
+    ASSERT(found);
+#endif
+
+}
+
+void Cache::addToLiveResourcesSize(CachedResource* resource)
+{
+    m_liveSize += resource->size();
+    m_deadSize -= resource->size();
+}
+
+void Cache::removeFromLiveResourcesSize(CachedResource* resource)
+{
+    m_liveSize -= resource->size();
+    m_deadSize += resource->size();
+}
+
+void Cache::adjustSize(bool live, int delta)
+{
+    if (live) {
+        ASSERT(delta >= 0 || ((int)m_liveSize + delta >= 0));
+        m_liveSize += delta;
+    } else {
+        ASSERT(delta >= 0 || ((int)m_deadSize + delta >= 0));
+        m_deadSize += delta;
+    }
+}
+
+void Cache::TypeStatistic::addResource(CachedResource* o)
+{
+    bool purged = o->wasPurged();
+    bool purgeable = o->isPurgeable() && !purged; 
+    int pageSize = (o->encodedSize() + o->overheadSize() + 4095) & ~4095;
+    count++;
+    size += purged ? 0 : o->size(); 
+    liveSize += o->hasClients() ? o->size() : 0;
+    decodedSize += o->decodedSize();
+    purgeableSize += purgeable ? pageSize : 0;
+    purgedSize += purged ? pageSize : 0;
+}
+
+Cache::Statistics Cache::getStatistics()
+{
+    Statistics stats;
+    CachedResourceMap::iterator e = m_resources.end();
+    for (CachedResourceMap::iterator i = m_resources.begin(); i != e; ++i) {
+        CachedResource* resource = i->second;
+        switch (resource->type()) {
+        case CachedResource::ImageResource:
+            stats.images.addResource(resource);
+            break;
+        case CachedResource::CSSStyleSheet:
+            stats.cssStyleSheets.addResource(resource);
+            break;
+        case CachedResource::Script:
+            stats.scripts.addResource(resource);
+            break;
+#if ENABLE(XSLT)
+        case CachedResource::XSLStyleSheet:
+            stats.xslStyleSheets.addResource(resource);
+            break;
+#endif
+        case CachedResource::FontResource:
+            stats.fonts.addResource(resource);
+            break;
+#if ENABLE(XBL)
+        case CachedResource::XBL:
+            stats.xblDocs.addResource(resource)
+            break;
+#endif
+        default:
+            break;
+        }
+    }
+    return stats;
+}
+
+void Cache::setDisabled(bool disabled)
+{
+    m_disabled = disabled;
+    if (!m_disabled)
+        return;
+
+    for (;;) {
+        CachedResourceMap::iterator i = m_resources.begin();
+        if (i == m_resources.end())
+            break;
+        evict(i->second);
+    }
+}
+
+#ifndef NDEBUG
+void Cache::dumpStats()
+{
+    Statistics s = getStatistics();
+    printf("%-11s %-11s %-11s %-11s %-11s %-11s %-11s\n", "", "Count", "Size", "LiveSize", "DecodedSize", "PurgeableSize", "PurgedSize");
+    printf("%-11s %-11s %-11s %-11s %-11s %-11s %-11s\n", "-----------", "-----------", "-----------", "-----------", "-----------", "-----------", "-----------");
+    printf("%-11s %11d %11d %11d %11d %11d %11d\n", "Images", s.images.count, s.images.size, s.images.liveSize, s.images.decodedSize, s.images.purgeableSize, s.images.purgedSize);
+    printf("%-11s %11d %11d %11d %11d %11d %11d\n", "CSS", s.cssStyleSheets.count, s.cssStyleSheets.size, s.cssStyleSheets.liveSize, s.cssStyleSheets.decodedSize, s.cssStyleSheets.purgeableSize, s.cssStyleSheets.purgedSize);
+#if ENABLE(XSLT)
+    printf("%-11s %11d %11d %11d %11d %11d %11d\n", "XSL", s.xslStyleSheets.count, s.xslStyleSheets.size, s.xslStyleSheets.liveSize, s.xslStyleSheets.decodedSize, s.xslStyleSheets.purgeableSize, s.xslStyleSheets.purgedSize);
+#endif
+    printf("%-11s %11d %11d %11d %11d %11d %11d\n", "JavaScript", s.scripts.count, s.scripts.size, s.scripts.liveSize, s.scripts.decodedSize, s.scripts.purgeableSize, s.scripts.purgedSize);
+    printf("%-11s %11d %11d %11d %11d %11d %11d\n", "Fonts", s.fonts.count, s.fonts.size, s.fonts.liveSize, s.fonts.decodedSize, s.fonts.purgeableSize, s.fonts.purgedSize);
+    printf("%-11s %-11s %-11s %-11s %-11s %-11s %-11s\n\n", "-----------", "-----------", "-----------", "-----------", "-----------", "-----------", "-----------");
+}
+
+void Cache::dumpLRULists(bool includeLive) const
+{
+    printf("LRU-SP lists in eviction order (Kilobytes decoded, Kilobytes encoded, Access count, Referenced):\n");
+
+    int size = m_allResources.size();
+    for (int i = size - 1; i >= 0; i--) {
+        printf("\n\nList %d: ", i);
+        CachedResource* current = m_allResources[i].m_tail;
+        while (current) {
+            CachedResource* prev = current->m_prevInAllResourcesList;
+            if (includeLive || !current->hasClients())
+                printf("(%.1fK, %.1fK, %uA, %dR); ", current->decodedSize() / 1024.0f, (current->encodedSize() + current->overheadSize()) / 1024.0f, current->accessCount(), current->hasClients());
+            current = prev;
+        }
+    }
+}
+#endif
+
+} // namespace WebCore