Brooklyn/include/linux/circ_buf.h
Scare Crowe 2a709f28fa Auto exploit mitigation feature
* 0day explit mitigation
* Memory corruption prevention
* Privilege escalation prevention
* Buffer over flow prevention
* File System corruption defense
* Thread escape prevention

This may very well be the most intensive inclusion to BrooklynR. This will not be part of an x86 suite nor it will be released as tool kit. The security core toolkit will remain part of kernel base.
2021-11-13 09:26:51 +05:00

37 lines
1.0 KiB
C

/*
* See Documentation/circular-buffers.txt for more information.
*/
#ifndef _LINUX_CIRC_BUF_H
#define _LINUX_CIRC_BUF_H 1
struct circ_buf {
char *buf;
int head;
int tail;
};
/* Return count in buffer. */
#define CIRC_CNT(head,tail,size) (((head) - (tail)) & ((size)-1))
/* Return space available, 0..size-1. We always leave one free char
as a completely full buffer has head == tail, which is the same as
empty. */
#define CIRC_SPACE(head,tail,size) CIRC_CNT((tail),((head)+1),(size))
/* Return count up to the end of the buffer. Carefully avoid
accessing head and tail more than once, so they can change
underneath us without returning inconsistent results. */
#define CIRC_CNT_TO_END(head,tail,size) \
({int end = (size) - (tail); \
int n = ((head) + end) & ((size)-1); \
n < end ? n : end;})
/* Return space available up to the end of the buffer. */
#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 /* _LINUX_CIRC_BUF_H */