root/include/linux/kmsg_dump.h

INCLUDED FROM

DEFINITIONS

1. kmsg_dump
2. kmsg_dump_get_line_nolock
3. kmsg_dump_get_line
4. kmsg_dump_get_buffer
5. kmsg_dump_rewind_nolock
6. kmsg_dump_rewind
7. kmsg_dump_register
8. kmsg_dump_unregister

/*
 * linux/include/kmsg_dump.h
 *
 * Copyright (C) 2009 Net Insight AB
 *
 * Author: Simon Kagstrom <simon.kagstrom@netinsight.net>
 *
 * 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 */