#ifndef _LINUX_STDDEF_H
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#define _LINUX_STDDEF_H
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#undef NULL
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#if defined(__cplusplus)
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#define NULL 0
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#else
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#define NULL ((void *)0)
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#endif
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#undef offsetof
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#define offsetof(TYPE, MEMBER) ((size_t) &((TYPE *)0)->MEMBER)
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/**
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* container_of - cast a member of a structure out to the containing structure
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*
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* @ptr: the pointer to the member.
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* @type: the type of the container struct this is embedded in.
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* @member: the name of the member within the struct.
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*
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*/
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#define container_of(ptr, type, member) ({ \
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const typeof( ((type *)0)->member ) *__mptr = (ptr); \
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(type *)( (char *)__mptr - offsetof(type,member) );})
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/*
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* Check at compile time that something is of a particular type.
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* Always evaluates to 1 so you may use it easily in comparisons.
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*/
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#define typecheck(type,x) \
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({ type __dummy; \
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typeof(x) __dummy2; \
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(void)(&__dummy == &__dummy2); \
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1; \
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})
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#endif
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