/*
* Copyright 2011 John-Mark Bell <jmb@netsurf-browser.org>
*
* This file is part of NetSurf, http://www.netsurf-browser.org/
*
* NetSurf is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; version 2 of the License.
*
* NetSurf 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 General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program. If not, see <http://www.gnu.org/licenses/>.
*/
/** \file
* The image content handler intermediate image cache.
*
* This cache allows netsurf to use a generic intermediate bitmap
* format without keeping the
* intermediate representation in memory.
*
* The bitmap structure is opaque to the rest of netsurf and is
* controlled by the platform-specific code (see image/bitmap.h for
* detials). All image content handlers convert into this format and
* pass it to the plot functions for display,
*
* This cache maintains a link between the underlying original content
* and the intermediate representation. It is intended to be flexable
* and either manage the bitmap plotting completely or give the image
* content handler complete control.
*/
#ifndef NETSURF_IMAGE_IMAGE_CACHE_H_
#define NETSURF_IMAGE_IMAGE_CACHE_H_
#include "utils/errors.h"
#include "desktop/plotters.h"
#include "image/bitmap.h"
typedef struct bitmap * (image_cache_convert_fn) (struct content *content);
struct image_cache_parameters {
/** How frequently the background cache clean process is run (ms) */
unsigned int bg_clean_time;
/** The target upper bound for the image cache size */
size_t limit;
/** The hysteresis allowed round the target size */
size_t hysteresis;
/** The speculative conversion "small" size */
size_t speculative_small;
};
/** Initialise the image cache
*
* @param image_cache_parameters The control parameters for the image cache
*/
nserror image_cache_init(const struct image_cache_parameters *image_cache_parameters);
nserror image_cache_fini(void);
/** adds an image content to be cached.
*
* @param content The content handle used as a key
* @param bitmap A bitmap representing the already converted content or NULL.
* @param convert A function pointer to convert the content into a bitmap or NULL.
* @return A netsurf error code.
*/
nserror image_cache_add(struct content *content,
struct bitmap *bitmap,
image_cache_convert_fn *convert);
nserror image_cache_remove(struct content *content);
/** Obtain a bitmap from a content converting from source if neccessary. */
struct bitmap *image_cache_get_bitmap(const struct content *c);
/** Obtain a bitmap from a content with no conversion */
struct bitmap *image_cache_find_bitmap(struct content *c);
/** Decide if a content should be speculatively converted.
*
* This allows for image content handlers to ask the cache if a bitmap
* should be generated before it is added to the cache. This is the
* same decision logic used to decide to perform an immediate
* conversion when a content is initially added to the cache.
*
* @param c The content to be considered.
* @return true if a speculative conversion is desired false otehrwise.
*/
bool image_cache_speculate(struct content *c);
/**
* Fill a buffer with information about a cache entry using a format.
*
* The format string is copied into the output buffer with the
* following replaced:
* %e - The entry number
* %k - The content key
* %r - The number of redraws of this bitmap
* %c - The number of times this bitmap has been converted
* %s - The size of the current bitmap allocation
*
* \param string The buffer in which to place the results.
* \param size The size of the string buffer.
* \param entryn The opaque entry number.
* \param fmt The format string.
* \return The number of bytes written to \a string or -1 on error
*/
int image_cache_snentryf(char *string, size_t size, unsigned int entryn,
const char *fmt);
/**
* Fill a buffer with information about the image cache using a format.
*
* The format string is copied into the output buffer with the
* following replaced:
*
* a Configured cache limit size
* b Configured cache hysteresis size
* c Current caches total consumed size
* d Number of images currently in the cache
* e The age of the cache
* f The largest amount of space the cache has occupied since initialisation
* g The number of objetcs when the cache was at its largest
* h The largest number of images in the cache since initialisation
* i The size of the cache when the largest number of objects occoured
* j The total number of read operations performed on the cache
* k The total number of read operations satisfied from the cache without
* conversion.
* l The total number of read operations satisfied from the cache which
* required a conversion.
* m The total number of read operations which could not be sucessfully
* returned. ie. not available in cache and conversion failed.
* n The total size of read operations performed on the cache
* o The total size of read operations satisfied from the cache without
* conversion.
* q The total size of read operations satisfied from the cache which
* required a conversion.
* r The total size of read operations which could not be sucessfully
* returned. ie. not available in cache and conversion failed.
* s The number of images which were placed in the cache but never read.
* t The number of images that were converted on insertion into teh cache which were subsequently never used.
* u The number of times an image was converted after the first
* v The number of images that had extra conversions performed.
* w Size of the image that was converted (read missed cache) highest number
* of times.
* x The number of times the image that was converted (read missed cache)
* highest number of times.
*
* format modifiers:
* A p before the value modifies the replacement to be a percentage.
*
*
* \param string The buffer in which to place the results.
* \param size The size of the string buffer.
* \param fmt The format string.
* \return The number of bytes written to \a string or -1 on error
*/
int image_cache_snsummaryf(char *string, size_t size, const char *fmt);
/********* Image content handler generic cache callbacks ************/
/** Generic content redraw callback
*
* May be used by image content handlers as their redraw
* callback. Performs all neccissary cache lookups and conversions and
* calls the bitmap plot function in the redraw context.
*/
bool image_cache_redraw(struct content *c,
struct content_redraw_data *data,
const struct rect *clip,
const struct redraw_context *ctx);
void image_cache_destroy(struct content *c);
void *image_cache_get_internal(const struct content *c, void *context);
content_type image_cache_content_type(void);
#endif