// SPDX-License-Identifier: ISC
/*	$OpenBSD$	*/

/*
 * Copyright (c) 2006, 2007 Pierre-Yves Ritschard <pyr@openbsd.org>
 * Copyright (c) 2006, 2007, 2008 Reyk Floeter <reyk@openbsd.org>
 * Copyright (c) 2003, 2004 Henning Brauer <henning@openbsd.org>
 */

#ifndef _IMSG_H_
#define _IMSG_H_

#ifdef __cplusplus
extern "C" {
#endif

#define IBUF_READ_SIZE		65535
#define IMSG_HEADER_SIZE	sizeof(struct imsg_hdr)
#define MAX_IMSGSIZE		16384

struct ibuf {
	TAILQ_ENTRY(ibuf) entry;
	uint8_t *buf;
	size_t size;
	size_t max;
	size_t wpos;
	size_t rpos;
	int fd;
};

struct msgbuf {
	TAILQ_HEAD(, ibuf) bufs;
	uint32_t queued;
	int fd;
};

struct ibuf_read {
	uint8_t buf[IBUF_READ_SIZE];
	uint8_t *rptr;
	size_t wpos;
};

struct imsg_fd {
	TAILQ_ENTRY(imsg_fd) entry;
	int fd;
};

struct imsgbuf {
	TAILQ_HEAD(, imsg_fd) fds;
	struct ibuf_read r;
	struct msgbuf w;
	int fd;
	pid_t pid;
};

#define IMSGF_HASFD	1

struct imsg_hdr {
	uint32_t type;
	uint16_t len;
	uint16_t flags;
	uint32_t peerid;
	uint32_t pid;
};

struct imsg {
	struct imsg_hdr hdr;
	int fd;
	void *data;
};


/* buffer.c */
struct ibuf *ibuf_open(size_t);
struct ibuf *ibuf_dynamic(size_t, size_t);
int ibuf_add(struct ibuf *, const void *, size_t);
void *ibuf_reserve(struct ibuf *, size_t);
void *ibuf_seek(struct ibuf *, size_t, size_t);
size_t ibuf_size(struct ibuf *);
size_t ibuf_left(struct ibuf *);
void ibuf_close(struct msgbuf *, struct ibuf *);
int ibuf_write(struct msgbuf *);
void ibuf_free(struct ibuf *);
void msgbuf_init(struct msgbuf *);
void msgbuf_clear(struct msgbuf *);
int msgbuf_write(struct msgbuf *);
void msgbuf_drain(struct msgbuf *, size_t);

/* imsg.c */
void imsg_init(struct imsgbuf *, int);
ssize_t imsg_read(struct imsgbuf *);
ssize_t imsg_get(struct imsgbuf *, struct imsg *);
int imsg_compose(struct imsgbuf *, uint32_t, uint32_t, pid_t, int, const void *,
		 uint16_t);
int imsg_composev(struct imsgbuf *, uint32_t, uint32_t, pid_t, int,
		  const struct iovec *, int);
struct ibuf *imsg_create(struct imsgbuf *, uint32_t, uint32_t, pid_t, uint16_t);
int imsg_add(struct ibuf *, const void *, uint16_t);
void imsg_close(struct imsgbuf *, struct ibuf *);
void imsg_free(struct imsg *);
int imsg_flush(struct imsgbuf *);
void imsg_clear(struct imsgbuf *);

#ifdef __cplusplus
}
#endif

#endif