/*-
 * Copyright (c) 2006 Verdens Gang AS
 * Copyright (c) 2006-2011 Varnish Software AS
 * All rights reserved.
 *
 * Author: Poul-Henning Kamp <phk@phk.freebsd.dk>
 *
 * SPDX-License-Identifier: BSD-2-Clause
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 *
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED.  IN NO EVENT SHALL AUTHOR OR CONTRIBUTORS BE LIABLE
 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 *
 * This defines the backend interface between the stevedore and the
 * pluggable storage implementations.
 *
 */

struct stevedore;
struct sess;
struct objcore;
struct worker;
struct lru;
struct vsl_log;
struct vfp_ctx;
struct obj_methods;

enum baninfo {
	BI_NEW,
	BI_DROP
};

/* Prototypes --------------------------------------------------------*/

typedef void storage_init_f(struct stevedore *, int ac, char * const *av);
typedef void storage_open_f(struct stevedore *);
typedef int storage_allocobj_f(struct worker *, const struct stevedore *,
    struct objcore *, unsigned);
typedef void storage_close_f(const struct stevedore *, int pass);
typedef int storage_baninfo_f(const struct stevedore *, enum baninfo event,
    const uint8_t *ban, unsigned len);
typedef void storage_banexport_f(const struct stevedore *, const uint8_t *bans,
    unsigned len);
typedef void storage_panic_f(struct vsb *vsb, const struct objcore *oc);

typedef void *storage_allocbuf_f(struct worker *, const struct stevedore *,
    size_t size, uintptr_t *ppriv);
typedef void storage_freebuf_f(struct worker *, const struct stevedore *,
    uintptr_t priv);

struct storage;
typedef struct object *sml_getobj_f(struct worker *, struct objcore *);
typedef struct storage *sml_alloc_f(const struct stevedore *, size_t size);
typedef void sml_free_f(struct storage *);

/* Prototypes for VCL variable responders */
#define VRTSTVVAR(nm,vt,ct,def) \
    typedef ct stv_var_##nm(const struct stevedore *);
#include "tbl/vrt_stv_var.h"

/*--------------------------------------------------------------------*/

struct stevedore {
	unsigned			magic;
#define STEVEDORE_MAGIC			0x4baf43db
	const char			*name;

	/* Called in MGT process */
	storage_init_f			*init;

	/* Called in cache process
	 * only allocobj is required, other callbacks are optional
	 */
	storage_open_f			*open;
	storage_close_f			*close;
	storage_allocobj_f		*allocobj;
	storage_baninfo_f		*baninfo;
	storage_banexport_f		*banexport;
	storage_panic_f			*panic;
	storage_allocbuf_f		*allocbuf;
	storage_freebuf_f		*freebuf;

	/* Only if SML is used */
	sml_alloc_f			*sml_alloc;
	sml_free_f			*sml_free;
	sml_getobj_f			*sml_getobj;

	const struct obj_methods	*methods;

	/* Only if LRU is used */
	struct lru			*lru;

#define VRTSTVVAR(nm, vtype, ctype, dval) stv_var_##nm *var_##nm;
#include "tbl/vrt_stv_var.h"

	/* private fields for the stevedore */
	void				*priv;

	VTAILQ_ENTRY(stevedore)	list;
	const char			*ident;
	const char			*vclname;
};

extern struct stevedore *stv_transient;
extern struct stevedore *stv_h2_rxbuf;

/*--------------------------------------------------------------------*/

#define STV_Foreach(arg) for (arg = NULL; STV__iter(&arg);)

int STV__iter(struct stevedore ** const );

/*--------------------------------------------------------------------*/
int STV_GetFile(const char *fn, int *fdp, const char **fnp, const char *ctx);
uintmax_t STV_FileSize(int fd, const char *size, unsigned *granularity,
    const char *ctx);

/*--------------------------------------------------------------------*/
struct lru *LRU_Alloc(void);
void LRU_Free(struct lru **);
void LRU_Add(struct objcore *, vtim_real now);
void LRU_Remove(struct objcore *);
int LRU_NukeOne(struct worker *, struct lru *);
void LRU_Touch(struct worker *, struct objcore *, vtim_real now);

/*--------------------------------------------------------------------*/
extern const struct stevedore smu_stevedore;
extern const struct stevedore sma_stevedore;
extern const struct stevedore smd_stevedore;
extern const struct stevedore smf_stevedore;
extern const struct stevedore smp_stevedore;
