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o Reformat comment and correct typo.
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@ -12,42 +12,35 @@
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/*
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* The pool allocator is useful when you are going
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* to allocate lots of memory, use the memory for
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* a bit, and then free the memory in one go. A
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* surprising amount of code has this usage
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* The pool allocator is useful when you are going to allocate
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* lots of memory, use the memory for a bit, and then free the
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* memory in one go. A surprising amount of code has this usage
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* profile.
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*
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* You should think of the pool as an infinite,
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* contigous chunk of memory. The front of this
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* chunk of memory contains allocated objects, the
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* second half is free. pool_alloc grabs the next
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* 'size' bytes from the free half, in effect
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* moving it into the allocated half. This
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* operation is very efficient.
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* You should think of the pool as an infinite, contiguous chunk
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* of memory. The front of this chunk of memory contains
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* allocated objects, the second half is free. pool_alloc grabs
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* the next 'size' bytes from the free half, in effect moving it
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* into the allocated half. This operation is very efficient.
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*
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* pool_free frees the allocated object *and* all
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* objects allocated after it. It is important to
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* note this semantic difference from malloc/free.
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* This is also extremely efficient, since a
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* single pool_free can dispose of a large complex
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* object.
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* pool_free frees the allocated object *and* all objects
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* allocated after it. It is important to note this semantic
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* difference from malloc/free. This is also extremely
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* efficient, since a single pool_free can dispose of a large
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* complex object.
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*
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* pool_destroy frees all allocated memory.
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*
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* eg, If you are building a binary tree in your
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* program, and know that you are only ever going
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* to insert into your tree, and not delete (eg,
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* maintaining a symbol table for a compiler).
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* You can create yourself a pool, allocate the
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* nodes from it, and when the tree becomes
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* redundant call pool_destroy (no nasty iterating
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* through the tree to free nodes).
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* eg, If you are building a binary tree in your program, and
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* know that you are only ever going to insert into your tree,
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* and not delete (eg, maintaining a symbol table for a
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* compiler). You can create yourself a pool, allocate the nodes
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* from it, and when the tree becomes redundant call pool_destroy
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* (no nasty iterating through the tree to free nodes).
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*
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* eg, On the other hand if you wanted to
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* repeatedly insert and remove objects into the
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* tree, you would be better off allocating the
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* nodes from a free list; you cannot free a
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* eg, On the other hand if you wanted to repeatedly insert and
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* remove objects into the tree, you would be better off
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* allocating the nodes from a free list; you cannot free a
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* single arbitrary node with pool.
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*/
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