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/** |
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* balloc.h: Block allocation of memory segments. |
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* |
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* Copyright © 2007 Pippijn van Steenhoven / The Ermyth Team |
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* Rights to this code are as documented in doc/pod/gplicense.pod. |
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* |
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* $Id: balloc.h,v 1.3 2007-09-05 11:23:13 pippijn Exp $ |
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*/ |
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|
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#ifndef ERMYTH_BALLOC_H |
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#define ERMYTH_BALLOC_H |
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|
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#include <vector> |
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|
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extern void (*NullDealloc)(void*); |
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extern void (*NullNDealloc)(void*, size_t); |
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|
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template<class T, |
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int NewInit = 100, // The number of elements that should be allocated |
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// if we give out our last element |
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void* (*Alloc) (size_t) = &::operator new, |
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void (*Dealloc) (void *) = &::operator delete, |
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void (*NDealloc) (void *, size_t) = NullNDealloc> |
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struct balloc |
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{ |
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static void initialise (int chunks = 100) |
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{ |
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for (int i = 0; i < chunks; ++i) |
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{ |
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T *p = static_cast<T *> (Alloc (sizeof (T))); |
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T::get_list ().push_back (p); |
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} |
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} |
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|
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static void finalise () |
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{ |
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typename alloc_vector::iterator first = T::get_list ().begin (); |
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typename alloc_vector::iterator last = T::get_list ().end (); |
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while (first != last) |
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{ |
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T *p = *first; |
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++first; |
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if (NDealloc != NullNDealloc) |
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NDealloc (p, sizeof (T)); |
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else |
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Dealloc (p); |
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} |
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T::get_list ().clear (); |
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} |
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|
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void *operator new (size_t bytes) |
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{ |
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// extend our memory by another set of blocks if we run out of them |
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if (expect_false (T::get_list ().size () == 0)) |
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T::initialise (NewInit); |
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|
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T *p = T::get_list ().back (); |
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T::get_list ().pop_back (); |
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return p; |
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} |
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|
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void operator delete (void *p) |
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{ |
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// this cast is legal, because we know that p will always be of type T * |
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T::get_list ().push_back (static_cast<T *> (p)); |
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} |
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|
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protected: |
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balloc () |
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{ |
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} |
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|
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virtual ~balloc () |
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{ |
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} |
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|
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private: |
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typedef std::vector<T *> alloc_vector; |
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|
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static alloc_vector &get_list () |
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{ |
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static alloc_vector m_free; |
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return m_free; |
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} |
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}; |
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|
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#endif |
