WebCache.h

/*
 * Copyright (C) 2009 Google Inc. All rights reserved.
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 * modification, are permitted provided that the following conditions are
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 * in the documentation and/or other materials provided with the
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 * this software without specific prior written permission.
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 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
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#ifndef WebCache_h
#define WebCache_h

#include "../../../Platform/chromium/public/WebCommon.h"

namespace WebKit {

// An interface to query and configure WebKit's resource cache.
class WebCache {
public:
    struct UsageStats {
        // Capacities.
        size_t minDeadCapacity;
        size_t maxDeadCapacity;
        size_t capacity;
        // Utilization.
        size_t liveSize;
        size_t deadSize;
    };

    // A struct mirroring WebCore::MemoryCache::TypeStatistic.
    struct ResourceTypeStat {
        size_t count;
        size_t size;
        size_t liveSize;
        size_t decodedSize;
    };

    // A struct mirroring WebCore::MemoryCache::Statistics.
    struct ResourceTypeStats {
        ResourceTypeStat images;
        ResourceTypeStat cssStyleSheets;
        ResourceTypeStat scripts;
        ResourceTypeStat xslStyleSheets;
        ResourceTypeStat fonts;
    };

    // Sets the capacities of the resource cache, evicting objects as necessary.
    WEBKIT_EXPORT static void setCapacities(size_t minDeadCapacity,
                                            size_t maxDeadCapacity,
                                            size_t capacity);

    // Clears the cache (as much as possible; some resources may not be
    // cleared if they are actively referenced). Note that this method
    // only removes resources from live list, w/o releasing cache memory.
    WEBKIT_EXPORT static void clear();

    // Prunes resource cache. Destroys decoded images data and returns
    // memory to the system.
    WEBKIT_EXPORT static void prune();

    // Gets the usage statistics from the resource cache.
    WEBKIT_EXPORT static void getUsageStats(UsageStats*);

    // Get usage stats about the resource cache.
    WEBKIT_EXPORT static void getResourceTypeStats(ResourceTypeStats*);

private:
    WebCache();  // Not intended to be instanced.
};

}  // namespace WebKit

#endif