* @section MEM_CacheLimiter
* This class defines a generic memory cache management system
* to limit memory usage to a fixed global maximum.
- *
+ *
* Please use the C-API in MEM_CacheLimiterC-Api.h for code written in C.
*
* Usage example:
* public:
* ~BigFatImage() { tell_everyone_we_are_gone(this); }
* };
- *
+ *
* void doit() {
* MEM_Cache<BigFatImage> BigFatImages;
*
* MEM_Cache_Handle<BigFatImage>* h = BigFatImages.insert(new BigFatImage);
- *
+ *
* BigFatImages.enforce_limits();
* h->ref();
*
#ifndef __MEM_CACHELIMITERC_API_H__
extern "C" {
- extern void MEM_CacheLimiter_set_maximum(size_t m);
- extern size_t MEM_CacheLimiter_get_maximum();
+ void MEM_CacheLimiter_set_maximum(size_t m);
+ size_t MEM_CacheLimiter_get_maximum();
};
#endif
template<class T>
class MEM_CacheLimiterHandle {
public:
- explicit MEM_CacheLimiterHandle(T * data_,
- MEM_CacheLimiter<T> * parent_)
- : data(data_), refcount(0), parent(parent_) { }
-
- void ref() {
- refcount++;
+ explicit MEM_CacheLimiterHandle(T * data_,MEM_CacheLimiter<T> *parent_) :
+ data(data_),
+ refcount(0),
+ parent(parent_)
+ { }
+
+ void ref() {
+ refcount++;
}
- void unref() {
- refcount--;
+
+ void unref() {
+ refcount--;
}
- T * get() {
- return data;
+
+ T *get() {
+ return data;
}
- const T * get() const {
- return data;
+
+ const T *get() const {
+ return data;
}
- int get_refcount() const {
- return refcount;
+
+ int get_refcount() const {
+ return refcount;
}
- bool can_destroy() const {
- return !data || !refcount;
+
+ bool can_destroy() const {
+ return !data || !refcount;
}
+
bool destroy_if_possible() {
if (can_destroy()) {
delete data;
}
return false;
}
+
void unmanage() {
parent->unmanage(this);
}
+
void touch() {
parent->touch(this);
}
+
void set_priority(int priority) {
this->priority = priority;
}
+
int get_priority(void) {
return this->priority;
}
+
private:
friend class MEM_CacheLimiter<T>;
T * data;
int refcount;
int priority;
- typename std::list<MEM_CacheLimiterHandle<T> *,
- MEM_Allocator<MEM_CacheLimiterHandle<T> *> >::iterator me;
+ typename std::list<MEM_CacheLimiterHandle<T> *, MEM_Allocator<MEM_CacheLimiterHandle<T> *> >::iterator me;
MEM_CacheLimiter<T> * parent;
};
class MEM_CacheLimiter {
public:
typedef size_t (*MEM_CacheLimiter_DataSize_Func) (void *data);
- typedef int (*MEM_CacheLimiter_ItemPriority_Func) (void *item, int default_priority);
+ typedef int (*MEM_CacheLimiter_ItemPriority_Func) (void *item, int default_priority);
+
MEM_CacheLimiter(MEM_CacheLimiter_DataSize_Func getDataSize_)
: getDataSize(getDataSize_) {
}
+
~MEM_CacheLimiter() {
for (iterator it = queue.begin(); it != queue.end(); it++) {
delete *it;
}
}
- MEM_CacheLimiterHandle<T> * insert(T * elem) {
+
+ MEM_CacheLimiterHandle<T> *insert(T * elem) {
queue.push_back(new MEM_CacheLimiterHandle<T>(elem, this));
iterator it = queue.end();
--it;
queue.back()->me = it;
return queue.back();
}
- void unmanage(MEM_CacheLimiterHandle<T> * handle) {
+
+ void unmanage(MEM_CacheLimiterHandle<T> *handle) {
queue.erase(handle->me);
delete handle;
}
+
void enforce_limits() {
MEM_CachePriorityQueue priority_queue;
size_t max = MEM_CacheLimiter_get_maximum();
while (!priority_queue.empty() && mem_in_use > max) {
MEM_CacheElementPtr elem = priority_queue.top();
+ priority_queue.pop();
+
if(getDataSize) {
cur_size = getDataSize(elem->get()->get_data());
} else {
cur_size = mem_in_use;
}
- elem->destroy_if_possible();
-
- priority_queue.pop();
-
- if (getDataSize) {
- mem_in_use -= cur_size;
- } else {
- mem_in_use -= cur_size - MEM_get_memory_in_use();
+ if (elem->destroy_if_possible()) {
+ if (getDataSize) {
+ mem_in_use -= cur_size;
+ } else {
+ mem_in_use -= cur_size - MEM_get_memory_in_use();
+ }
}
}
}
+
void touch(MEM_CacheLimiterHandle<T> * handle) {
queue.push_back(handle);
queue.erase(handle->me);
--it;
handle->me = it;
}
+
void set_item_priority_func(MEM_CacheLimiter_ItemPriority_Func item_priority_func) {
getItemPriority = item_priority_func;
}
+
private:
typedef MEM_CacheLimiterHandle<T> *MEM_CacheElementPtr;
typedef std::list<MEM_CacheElementPtr, MEM_Allocator<MEM_CacheElementPtr> > MEM_CacheQueue;
#ifdef __cplusplus
extern "C" {
#endif
-
+
struct MEM_CacheLimiter_s;
struct MEM_CacheLimiterHandle_s;
typedef struct MEM_CacheLimiterHandle_s MEM_CacheLimiterHandleC;
/* function used to remove data from memory */
-typedef void(*MEM_CacheLimiter_Destruct_Func)(void*);
+typedef void (*MEM_CacheLimiter_Destruct_Func)(void*);
/* function used to measure stored data element size */
-typedef size_t(*MEM_CacheLimiter_DataSize_Func) (void*);
+typedef size_t (*MEM_CacheLimiter_DataSize_Func) (void*);
/* function used to measure priority of item when freeing memory */
-typedef int(*MEM_CacheLimiter_ItemPriority_Func) (void*, int);
+typedef int (*MEM_CacheLimiter_ItemPriority_Func) (void*, int);
#ifndef __MEM_CACHELIMITER_H__
-extern void MEM_CacheLimiter_set_maximum(size_t m);
-extern int MEM_CacheLimiter_get_maximum(void);
+void MEM_CacheLimiter_set_maximum(size_t m);
+int MEM_CacheLimiter_get_maximum(void);
#endif /* __MEM_CACHELIMITER_H__ */
-/**
- * Create new MEM_CacheLimiter object
+
+/**
+ * Create new MEM_CacheLimiter object
* managed objects are destructed with the data_destructor
*
* @param data_destructor
* @return A new MEM_CacheLimter object
*/
-extern MEM_CacheLimiterC * new_MEM_CacheLimiter(
- MEM_CacheLimiter_Destruct_Func data_destructor,
- MEM_CacheLimiter_DataSize_Func data_size);
+MEM_CacheLimiterC *new_MEM_CacheLimiter(MEM_CacheLimiter_Destruct_Func data_destructor,
+ MEM_CacheLimiter_DataSize_Func data_size);
-/**
+/**
* Delete MEM_CacheLimiter
- *
+ *
* Frees the memory of the CacheLimiter but does not touch managed objects!
*
* @param This "This" pointer
*/
-extern void delete_MEM_CacheLimiter(MEM_CacheLimiterC * This);
+void delete_MEM_CacheLimiter(MEM_CacheLimiterC *This);
-/**
+/**
* Manage object
- *
+ *
* @param This "This" pointer, data data object to manage
* @return CacheLimiterHandle to ref, unref, touch the managed object
*/
-
-extern MEM_CacheLimiterHandleC * MEM_CacheLimiter_insert(
- MEM_CacheLimiterC * This, void * data);
-/**
+MEM_CacheLimiterHandleC *MEM_CacheLimiter_insert(MEM_CacheLimiterC * This, void * data);
+
+/**
* Free objects until memory constraints are satisfied
- *
+ *
* @param This "This" pointer
*/
-extern void MEM_CacheLimiter_enforce_limits(MEM_CacheLimiterC * This);
+void MEM_CacheLimiter_enforce_limits(MEM_CacheLimiterC *This);
-/**
- * Unmanage object previously inserted object.
+/**
+ * Unmanage object previously inserted object.
* Does _not_ delete managed object!
- *
+ *
* @param This "This" pointer, handle of object
*/
-
-extern void MEM_CacheLimiter_unmanage(MEM_CacheLimiterHandleC * handle);
+void MEM_CacheLimiter_unmanage(MEM_CacheLimiterHandleC *handle);
-/**
+
+/**
* Raise priority of object (put it at the tail of the deletion chain)
- *
+ *
* @param handle of object
*/
-
-extern void MEM_CacheLimiter_touch(MEM_CacheLimiterHandleC * handle);
-/**
+void MEM_CacheLimiter_touch(MEM_CacheLimiterHandleC *handle);
+
+/**
* Increment reference counter. Objects with reference counter != 0 are _not_
* deleted.
- *
+ *
* @param handle of object
*/
-
-extern void MEM_CacheLimiter_ref(MEM_CacheLimiterHandleC * handle);
-/**
+void MEM_CacheLimiter_ref(MEM_CacheLimiterHandleC *handle);
+
+/**
* Decrement reference counter. Objects with reference counter != 0 are _not_
* deleted.
- *
+ *
* @param handle of object
*/
-
-extern void MEM_CacheLimiter_unref(MEM_CacheLimiterHandleC * handle);
-/**
+void MEM_CacheLimiter_unref(MEM_CacheLimiterHandleC *handle);
+
+/**
* Get reference counter.
- *
+ *
* @param This "This" pointer, handle of object
*/
-
-extern int MEM_CacheLimiter_get_refcount(MEM_CacheLimiterHandleC * handle);
-/**
+int MEM_CacheLimiter_get_refcount(MEM_CacheLimiterHandleC *handle);
+
+/**
* Get pointer to managed object
- *
+ *
* @param handle of object
*/
-
-extern void * MEM_CacheLimiter_get(MEM_CacheLimiterHandleC * handle);
-extern void MEM_CacheLimiter_ItemPriority_Func_set(MEM_CacheLimiterC *This,
- MEM_CacheLimiter_ItemPriority_Func item_priority_func);
+void * MEM_CacheLimiter_get(MEM_CacheLimiterHandleC *handle);
+
+void MEM_CacheLimiter_ItemPriority_Func_set(MEM_CacheLimiterC *This,
+ MEM_CacheLimiter_ItemPriority_Func item_priority_func);
#ifdef __cplusplus
}
static size_t & get_max()
{
- static size_t m = 32*1024*1024;
+ static size_t m = 32 * 1024 * 1024;
return m;
}
typedef MEM_CacheLimiterHandle<MEM_CacheLimiterHandleCClass> handle_t;
typedef MEM_CacheLimiter<MEM_CacheLimiterHandleCClass> cache_t;
-typedef std::list<MEM_CacheLimiterHandleCClass*,
- MEM_Allocator<MEM_CacheLimiterHandleCClass* > > list_t;
+typedef std::list<MEM_CacheLimiterHandleCClass*, MEM_Allocator<MEM_CacheLimiterHandleCClass* > > list_t;
class MEM_CacheLimiterCClass {
public:
: data_destructor(data_destructor_), cache(data_size) {
}
~MEM_CacheLimiterCClass();
-
+
handle_t * insert(void * data);
- void destruct(void * data,
- list_t::iterator it);
+ void destruct(void * data, list_t::iterator it);
cache_t * get_cache() {
return &cache;
MEM_CacheLimiter_Destruct_Func data_destructor;
MEM_CacheLimiter<MEM_CacheLimiterHandleCClass> cache;
-
+
list_t cclass_list;
};
class MEM_CacheLimiterHandleCClass {
public:
- MEM_CacheLimiterHandleCClass(void * data_,
- MEM_CacheLimiterCClass * parent_)
- : data(data_), parent(parent_) { }
+ MEM_CacheLimiterHandleCClass(void * data_, MEM_CacheLimiterCClass * parent_) :
+ data(data_),
+ parent(parent_)
+ { }
+
~MEM_CacheLimiterHandleCClass();
+
void set_iter(list_t::iterator it_) {
it = it_;
}
+
void set_data(void * data_) {
data = data_;
}
- void * get_data() const {
+
+ void *get_data() const {
return data;
}
+
private:
- void * data;
- MEM_CacheLimiterCClass * parent;
+ void *data;
+ MEM_CacheLimiterCClass *parent;
list_t::iterator it;
};
-handle_t * MEM_CacheLimiterCClass::insert(void * data)
+handle_t *MEM_CacheLimiterCClass::insert(void * data)
{
cclass_list.push_back(new MEM_CacheLimiterHandleCClass(data, this));
list_t::iterator it = cclass_list.end();
--it;
cclass_list.back()->set_iter(it);
-
+
return cache.insert(cclass_list.back());
}
-void MEM_CacheLimiterCClass::destruct(void * data, list_t::iterator it)
+void MEM_CacheLimiterCClass::destruct(void * data, list_t::iterator it)
{
data_destructor(data);
cclass_list.erase(it);
MEM_CacheLimiterCClass::~MEM_CacheLimiterCClass()
{
// should not happen, but don't leak memory in this case...
- for (list_t::iterator it = cclass_list.begin();
- it != cclass_list.end(); it++) {
+ for (list_t::iterator it = cclass_list.begin(); it != cclass_list.end(); it++) {
(*it)->set_data(0);
+
delete *it;
}
}
// ----------------------------------------------------------------------
-static inline MEM_CacheLimiterCClass* cast(MEM_CacheLimiterC * l)
+static inline MEM_CacheLimiterCClass *cast(MEM_CacheLimiterC *l)
{
- return (MEM_CacheLimiterCClass*) l;
+ return (MEM_CacheLimiterCClass *) l;
}
-static inline handle_t* cast(MEM_CacheLimiterHandleC * l)
+static inline handle_t *cast(MEM_CacheLimiterHandleC *l)
{
- return (handle_t*) l;
+ return (handle_t *) l;
}
-MEM_CacheLimiterC * new_MEM_CacheLimiter(
- MEM_CacheLimiter_Destruct_Func data_destructor,
- MEM_CacheLimiter_DataSize_Func data_size)
+MEM_CacheLimiterC *new_MEM_CacheLimiter(MEM_CacheLimiter_Destruct_Func data_destructor,
+ MEM_CacheLimiter_DataSize_Func data_size)
{
- return (MEM_CacheLimiterC*) new MEM_CacheLimiterCClass(
- data_destructor,
- data_size);
+ return (MEM_CacheLimiterC *) new MEM_CacheLimiterCClass(data_destructor, data_size);
}
-void delete_MEM_CacheLimiter(MEM_CacheLimiterC * This)
+void delete_MEM_CacheLimiter(MEM_CacheLimiterC *This)
{
delete cast(This);
}
-MEM_CacheLimiterHandleC * MEM_CacheLimiter_insert(
- MEM_CacheLimiterC * This, void * data)
+MEM_CacheLimiterHandleC *MEM_CacheLimiter_insert(MEM_CacheLimiterC *This, void *data)
{
return (MEM_CacheLimiterHandleC *) cast(This)->insert(data);
}
-void MEM_CacheLimiter_enforce_limits(MEM_CacheLimiterC * This)
+void MEM_CacheLimiter_enforce_limits(MEM_CacheLimiterC *This)
{
cast(This)->get_cache()->enforce_limits();
}
-
-void MEM_CacheLimiter_unmanage(MEM_CacheLimiterHandleC * handle)
+
+void MEM_CacheLimiter_unmanage(MEM_CacheLimiterHandleC *handle)
{
cast(handle)->unmanage();
}
-
-void MEM_CacheLimiter_touch(MEM_CacheLimiterHandleC * handle)
+
+void MEM_CacheLimiter_touch(MEM_CacheLimiterHandleC *handle)
{
cast(handle)->touch();
}
-
-void MEM_CacheLimiter_ref(MEM_CacheLimiterHandleC * handle)
+
+void MEM_CacheLimiter_ref(MEM_CacheLimiterHandleC *handle)
{
cast(handle)->ref();
}
-
-void MEM_CacheLimiter_unref(MEM_CacheLimiterHandleC * handle)
+
+void MEM_CacheLimiter_unref(MEM_CacheLimiterHandleC *handle)
{
cast(handle)->unref();
}
-int MEM_CacheLimiter_get_refcount(MEM_CacheLimiterHandleC * handle)
+int MEM_CacheLimiter_get_refcount(MEM_CacheLimiterHandleC *handle)
{
return cast(handle)->get_refcount();
}
-
-void * MEM_CacheLimiter_get(MEM_CacheLimiterHandleC * handle)
+void *MEM_CacheLimiter_get(MEM_CacheLimiterHandleC *handle)
{
return cast(handle)->get()->get_data();
}