textsearch.h

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#ifndef __LINUX_TEXTSEARCH_H
#define __LINUX_TEXTSEARCH_H

#include <linux/types.h>
#include <linux/list.h>
#include <linux/kernel.h>
#include <linux/err.h>
#include <linux/slab.h>

struct module;

struct ts_config;

#define TS_AUTOLOAD 1 /* Automatically load textsearch modules when needed */
#define TS_IGNORECASE   2 /* Searches string case insensitively */

struct ts_state
{
    unsigned int        offset;
    char            cb[40];
};

struct ts_ops
{
    const char      *name;
    struct ts_config *  (*init)(const void *, unsigned int, gfp_t, int);
    unsigned int        (*find)(struct ts_config *,
                    struct ts_state *);
    void            (*destroy)(struct ts_config *);
    void *          (*get_pattern)(struct ts_config *);
    unsigned int        (*get_pattern_len)(struct ts_config *);
    struct module       *owner;
    struct list_head    list;
};

struct ts_config
{
    struct ts_ops       *ops;
    int             flags;

    unsigned int        (*get_next_block)(unsigned int consumed,
                          const u8 **dst,
                          struct ts_config *conf,
                          struct ts_state *state);

    void            (*finish)(struct ts_config *conf,
                      struct ts_state *state);
};

static inline unsigned int textsearch_next(struct ts_config *conf,
                       struct ts_state *state)
{
    unsigned int ret = conf->ops->find(conf, state);

    if (conf->finish)
        conf->finish(conf, state);

    return ret;
}

static inline unsigned int textsearch_find(struct ts_config *conf,
                       struct ts_state *state)
{
    state->offset = 0;
    return textsearch_next(conf, state);
}

static inline void *textsearch_get_pattern(struct ts_config *conf)
{
    return conf->ops->get_pattern(conf);
}

static inline unsigned int textsearch_get_pattern_len(struct ts_config *conf)
{
    return conf->ops->get_pattern_len(conf);
}

extern int textsearch_register(struct ts_ops *);
extern int textsearch_unregister(struct ts_ops *);
extern struct ts_config *textsearch_prepare(const char *, const void *,
                        unsigned int, gfp_t, int);
extern void textsearch_destroy(struct ts_config *conf);
extern unsigned int textsearch_find_continuous(struct ts_config *,
                           struct ts_state *,
                           const void *, unsigned int);


#define TS_PRIV_ALIGNTO 8
#define TS_PRIV_ALIGN(len) (((len) + TS_PRIV_ALIGNTO-1) & ~(TS_PRIV_ALIGNTO-1))

static inline struct ts_config *alloc_ts_config(size_t payload,
                        gfp_t gfp_mask)
{
    struct ts_config *conf;

    conf = kzalloc(TS_PRIV_ALIGN(sizeof(*conf)) + payload, gfp_mask);
    if (conf == NULL)
        return ERR_PTR(-ENOMEM);

    return conf;
}

static inline void *ts_config_priv(struct ts_config *conf)
{
    return ((u8 *) conf + TS_PRIV_ALIGN(sizeof(struct ts_config)));
}

#endif