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/****************************************************************************
****************************************************************************
***
*** This header was automatically generated from a Linux kernel header
*** of the same name, to make information necessary for userspace to
*** call into the kernel available to libc. It contains only constants,
*** structures, and macros generated from the original header, and thus,
*** contains no copyrightable information.
***
****************************************************************************
****************************************************************************/
#ifndef _LINUX_CIRC_BUF_H
#define _LINUX_CIRC_BUF_H 1
struct circ_buf {
char *buf;
int head;
int tail;
};
#define CIRC_CNT(head,tail,size) (((head) - (tail)) & ((size)-1))
#define CIRC_SPACE(head,tail,size) CIRC_CNT((tail),((head)+1),(size))
#define CIRC_CNT_TO_END(head,tail,size) ({int end = (size) - (tail); int n = ((head) + end) & ((size)-1); n < end ? n : end;})
#define CIRC_SPACE_TO_END(head,tail,size) ({int end = (size) - 1 - (head); int n = (end + (tail)) & ((size)-1); n <= end ? n : end+1;})
#endif
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