/*
* linux/include/kmsg_dump.h
*
* Copyright (C) 2009 Net Insight AB
*
* Author: Simon Kagstrom <[email protected]>
*
* This file is subject to the terms and conditions of the GNU General Public
* License. See the file COPYING in the main directory of this archive
* for more details.
*/
#ifndef _LINUX_KMSG_DUMP_H
#define _LINUX_KMSG_DUMP_H

#include <linux/errno.h>
#include <linux/list.h>

/*
* Keep this list arranged in rough order of priority. Anything listed after
* KMSG_DUMP_OOPS will not be logged by default unless printk.always_kmsg_dump
* is passed to the kernel.
*/
enum kmsg_dump_reason {
KMSG_DUMP_UNDEF,
KMSG_DUMP_PANIC,
KMSG_DUMP_OOPS,
KMSG_DUMP_EMERG,
KMSG_DUMP_RESTART,
KMSG_DUMP_HALT,
KMSG_DUMP_POWEROFF,
};

/**
* struct kmsg_dumper - kernel crash message dumper structure
* @list: Entry in the dumper list (private)
* @dump: Call into dumping code which will retrieve the data with
* through the record iterator
* @max_reason: filter for highest reason number that should be dumped
* @registered: Flag that specifies if this is already registered
*/
struct kmsg_dumper {
struct list_head list;
void (*dump)(struct kmsg_dumper *dumper, enum kmsg_dump_reason reason);
enum kmsg_dump_reason max_reason;
bool active;
bool registered;

/* private state of the kmsg iterator */
u32 cur_idx;
u32 next_idx;
u64 cur_seq;
u64 next_seq;
};

#ifdef CONFIG_PRINTK
void kmsg_dump(enum kmsg_dump_reason reason);

bool kmsg_dump_get_line_nolock(struct kmsg_dumper *dumper, bool syslog,
char *line, size_t size, size_t *len);

bool kmsg_dump_get_line(struct kmsg_dumper *dumper, bool syslog,
char *line, size_t size, size_t *len);

bool kmsg_dump_get_buffer(struct kmsg_dumper *dumper, bool syslog,
char *buf, size_t size, size_t *len);

void kmsg_dump_rewind_nolock(struct kmsg_dumper *dumper);

void kmsg_dump_rewind(struct kmsg_dumper *dumper);

int kmsg_dump_register(struct kmsg_dumper *dumper);

int kmsg_dump_unregister(struct kmsg_dumper *dumper);
#else
static inline void kmsg_dump(enum kmsg_dump_reason reason)
{
}

static inline bool kmsg_dump_get_line_nolock(struct kmsg_dumper *dumper,
bool syslog, const char *line,
size_t size, size_t *len)
{
return false;
}

static inline bool kmsg_dump_get_line(struct kmsg_dumper *dumper, bool syslog,
const char *line, size_t size, size_t *len)
{
return false;
}

static inline bool kmsg_dump_get_buffer(struct kmsg_dumper *dumper, bool syslog,
char *buf, size_t size, size_t *len)
{
return false;
}

static inline void kmsg_dump_rewind_nolock(struct kmsg_dumper *dumper)
{
}

static inline void kmsg_dump_rewind(struct kmsg_dumper *dumper)
{
}

static inline int kmsg_dump_register(struct kmsg_dumper *dumper)
{
return -EINVAL;
}

static inline int kmsg_dump_unregister(struct kmsg_dumper *dumper)
{
return -EINVAL;
}
#endif

#endif /* _LINUX_KMSG_DUMP_H */