rapidjson::Allocator Class Reference

Concept for allocating, resizing and freeing memory block. More...

#include <allocators.h>

Detailed Description

Concept for allocating, resizing and freeing memory block.

Note that Malloc() and Realloc() are non-static but Free() is static.

So if an allocator need to support Free(), it needs to put its pointer in the header of memory block.

concept Allocator {
    static const bool kNeedFree;    

    // Allocate a memory block.
    // \param size of the memory block in bytes.
    // \returns pointer to the memory block.
    void* Malloc(size_t size);

    // Resize a memory block.
    // \param originalPtr The pointer to current memory block. Null pointer is permitted.
    // \param originalSize The current size in bytes. (Design issue: since some allocator may not book-keep this, explicitly pass to it can save memory.)
    // \param newSize the new size in bytes.
    void* Realloc(void* originalPtr, size_t originalSize, size_t newSize);

    // Free a memory block.
    // \param pointer to the memory block. Null pointer is permitted.
    static void Free(void *ptr);
};