Return to framebuf.c CVS log

Up to [cvs.NetBSD.org] / src / lib / libpuffs

Change the signature of puffs_respcmp to return -1,0,1 for smaller,
equal, larger, respectively instead of 0/1 for non/equal.  This
will allow sorting the buffers for faster matching in libpuffs.
While here, change the name from respcmp to framecmp, as that better
reflects the purpose.

NOTE!  there is no obvious way to make compilation fail for file
systems which may already be using this feature (although I don't
think there are any outside our tree, as the feature is two weeks
old).  Nevertheless, non-updated file systems will fail very quickly.

/*	$NetBSD: framebuf.c,v 1.12 2007/05/20 16:24:37 pooka Exp $	*/

/*
 * Copyright (c) 2007  Antti Kantee.  All Rights Reserved.
 *
 * Development of this software was supported by the
 * Finnish Cultural Foundation.
 *
 * 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 ``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 THE 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.
 */

#include <sys/cdefs.h>
#if !defined(lint)
__RCSID("$NetBSD: framebuf.c,v 1.12 2007/05/20 16:24:37 pooka Exp $");
#endif /* !lint */

#include <sys/types.h>
#include <sys/queue.h>

#include <assert.h>
#include <errno.h>
#include <poll.h>
#include <puffs.h>
#include <stdlib.h>
#include <unistd.h>

#include "puffs_priv.h"

struct puffs_framebuf {
	struct puffs_cc *pcc;	/* pcc to continue with */
	/* OR */
	puffs_framev_cb fcb;	/* non-blocking callback */
	void *fcb_arg;		/* argument for previous */

	uint8_t *buf;		/* buffer base */
	size_t len;		/* total length */

	size_t offset;		/* cursor, telloff() */
	size_t maxoff;		/* maximum offset for data, tellsize() */

	volatile int rv;	/* errno value */

	int	istat;

	TAILQ_ENTRY(puffs_framebuf) pfb_entries;
};
#define ISTAT_NODESTROY	0x01	/* indestructible by framebuf_destroy() */
#define ISTAT_INTERNAL	0x02	/* never leaves library			*/
#define ISTAT_NOREPLY	0x04	/* nuke after sending 			*/

#define PUFBUF_INCRALLOC 4096
#define PUFBUF_REMAIN(p) (p->len - p->offset)

static struct puffs_fctrl_io *
getfiobyfd(struct puffs_usermount *pu, int fd)
{
	struct puffs_framectrl *pfctrl = &pu->pu_framectrl;
	struct puffs_fctrl_io *fio;

	LIST_FOREACH(fio, &pfctrl->fb_ios, fio_entries)
		if (fio->io_fd == fd)
			return fio;
	return NULL;
}

struct puffs_framebuf *
puffs_framebuf_make()
{
	struct puffs_framebuf *pufbuf;

	pufbuf = malloc(sizeof(struct puffs_framebuf));
	if (pufbuf == NULL)
		return NULL;
	memset(pufbuf, 0, sizeof(struct puffs_framebuf));

	pufbuf->buf = malloc(PUFBUF_INCRALLOC);
	if (pufbuf->buf == NULL) {
		free(pufbuf);
		return NULL;
	}
	pufbuf->len = PUFBUF_INCRALLOC;

	puffs_framebuf_recycle(pufbuf);
	return pufbuf;
}

void
puffs_framebuf_destroy(struct puffs_framebuf *pufbuf)
{

	assert((pufbuf->istat & ISTAT_NODESTROY) == 0);

	free(pufbuf->buf);
	free(pufbuf);
}

void
puffs_framebuf_recycle(struct puffs_framebuf *pufbuf)
{

	assert((pufbuf->istat & ISTAT_NODESTROY) == 0);

	pufbuf->offset = 0;
	pufbuf->maxoff = 0;
	pufbuf->istat = 0;
}

static int
reservespace(struct puffs_framebuf *pufbuf, size_t off, size_t wantsize)
{
	size_t incr;
	void *nd;

	if (off <= pufbuf->len && pufbuf->len - off >= wantsize)
		return 0;

	for (incr = PUFBUF_INCRALLOC;
	    pufbuf->len + incr < off + wantsize;
	    incr += PUFBUF_INCRALLOC)
		continue;

	nd = realloc(pufbuf->buf, pufbuf->offset + incr);
	if (nd == NULL)
		return -1;

	pufbuf->buf = nd;
	pufbuf->len += incr;

	return 0;
}

int
puffs_framebuf_reserve_space(struct puffs_framebuf *pufbuf, size_t wantsize)
{

	return reservespace(pufbuf, pufbuf->offset, wantsize);
}

int
puffs_framebuf_putdata(struct puffs_framebuf *pufbuf,
	const void *data, size_t dlen)
{

	if (PUFBUF_REMAIN(pufbuf) < dlen)
		if (puffs_framebuf_reserve_space(pufbuf, dlen) == -1)
			return -1;

	memcpy(pufbuf->buf + pufbuf->offset, data, dlen);
	pufbuf->offset += dlen;

	if (pufbuf->offset > pufbuf->maxoff)
		pufbuf->maxoff = pufbuf->offset;

	return 0;
}

int
puffs_framebuf_putdata_atoff(struct puffs_framebuf *pufbuf, size_t offset,
	const void *data, size_t dlen)
{

	if (reservespace(pufbuf, offset, dlen) == -1)
		return -1;

	memcpy(pufbuf->buf + offset, data, dlen);

	if (offset + dlen > pufbuf->maxoff)
		pufbuf->maxoff = offset + dlen;

	return 0;
}

int
puffs_framebuf_getdata(struct puffs_framebuf *pufbuf, void *data, size_t dlen)
{

	if (pufbuf->maxoff < pufbuf->offset + dlen) {
		errno = ENOBUFS;
		return -1;
	}

	memcpy(data, pufbuf->buf + pufbuf->offset, dlen);
	pufbuf->offset += dlen;

	return 0;
}

int
puffs_framebuf_getdata_atoff(struct puffs_framebuf *pufbuf, size_t offset,
	void *data, size_t dlen)
{

	if (pufbuf->maxoff < offset + dlen) {
		errno = ENOBUFS;
		return -1;
	}

	memcpy(data, pufbuf->buf + offset, dlen);
	return 0;
}

size_t
puffs_framebuf_telloff(struct puffs_framebuf *pufbuf)
{

	return pufbuf->offset;
}

size_t
puffs_framebuf_tellsize(struct puffs_framebuf *pufbuf)
{

	return pufbuf->maxoff;
}

size_t
puffs_framebuf_remaining(struct puffs_framebuf *pufbuf)
{

	return puffs_framebuf_tellsize(pufbuf) - puffs_framebuf_telloff(pufbuf);
}

int
puffs_framebuf_seekset(struct puffs_framebuf *pufbuf, size_t newoff)
{

	if (reservespace(pufbuf, newoff, 0) == -1)
		return -1;

	pufbuf->offset = newoff;
	return 0;
}

int
puffs_framebuf_getwindow(struct puffs_framebuf *pufbuf, size_t winoff,
	void **data, size_t *dlen)
{
	size_t winlen;

#ifdef WINTESTING
	winlen = MIN(*dlen, 32);
#else
	winlen = *dlen;
#endif

	if (reservespace(pufbuf, winoff, winlen) == -1)
		return -1;

	*data = pufbuf->buf + winoff;
	if (pufbuf->maxoff < winoff + winlen)
		pufbuf->maxoff = winoff + winlen;

	return 0;
}

static void
errnotify(struct puffs_framebuf *pufbuf, int error)
{

	pufbuf->rv = error;
	if (pufbuf->pcc) {
		puffs_goto(pufbuf->pcc);
	} else if (pufbuf->fcb) {
		pufbuf->istat &= ~ISTAT_NODESTROY;
		pufbuf->fcb(puffs_cc_getusermount(pufbuf->pcc),
		    pufbuf, pufbuf->fcb_arg, error);
	} else {
		pufbuf->istat &= ~ISTAT_NODESTROY;
		puffs_framebuf_destroy(pufbuf);
	}
}

#define GETFIO(fd)							\
do {									\
	fio = getfiobyfd(pu, fd);					\
	if (fio == NULL) {						\
		errno = EINVAL;						\
		return -1;						\
	}								\
	if (fio->stat & FIO_WRGONE) {					\
		errno = ESHUTDOWN;					\
		return -1;						\
	}								\
} while (/*CONSTCOND*/0)

int
puffs_framev_enqueue_cc(struct puffs_cc *pcc, int fd,
	struct puffs_framebuf *pufbuf)
{
	struct puffs_usermount *pu = puffs_cc_getusermount(pcc);
	struct puffs_fctrl_io *fio;

	/*
	 * Technically we shouldn't allow this is RDGONE, but it's
	 * difficult to trap write close without allowing writes.
	 * And besides, there's probably a disconnect sequence in
	 * the protocol, so unexpectedly getting a closed fd is
	 * most likely an error condition.
	 */
	GETFIO(fd);

	pufbuf->pcc = pcc;
	pufbuf->fcb = NULL;
	pufbuf->fcb_arg = NULL;

	pufbuf->offset = 0;
	pufbuf->istat |= ISTAT_NODESTROY;

	TAILQ_INSERT_TAIL(&fio->snd_qing, pufbuf, pfb_entries);

	puffs_cc_yield(pcc);
	if (pufbuf->rv) {
		pufbuf->istat &= ~ISTAT_NODESTROY;
		errno = pufbuf->rv;
		return -1;
	}

	return 0;
}

int
puffs_framev_enqueue_cb(struct puffs_usermount *pu, int fd,
	struct puffs_framebuf *pufbuf, puffs_framev_cb fcb, void *arg)
{
	struct puffs_fctrl_io *fio;

	/* see enqueue_cc */
	GETFIO(fd);

	pufbuf->pcc = NULL;
	pufbuf->fcb = fcb;
	pufbuf->fcb_arg = arg;

	pufbuf->offset = 0;
	pufbuf->istat |= ISTAT_NODESTROY;

	TAILQ_INSERT_TAIL(&fio->snd_qing, pufbuf, pfb_entries);

	return 0;
}

int
puffs_framev_enqueue_justsend(struct puffs_usermount *pu, int fd,
	struct puffs_framebuf *pufbuf, int reply)
{
	struct puffs_fctrl_io *fio;

	GETFIO(fd);

	pufbuf->pcc = NULL;
	pufbuf->fcb = NULL;
	pufbuf->fcb_arg = NULL;

	pufbuf->offset = 0;
	pufbuf->istat |= ISTAT_NODESTROY;
	if (!reply)
		pufbuf->istat |= ISTAT_NOREPLY;

	TAILQ_INSERT_TAIL(&fio->snd_qing, pufbuf, pfb_entries);

	return 0;
}

static struct puffs_framebuf *
findbuf(struct puffs_usermount *pu, struct puffs_framectrl *fctrl,
	struct puffs_fctrl_io *fio, struct puffs_framebuf *findme)
{
	struct puffs_framebuf *cand;

	TAILQ_FOREACH(cand, &fio->res_qing, pfb_entries)
		if (fctrl->cmpfb(pu, findme, cand) == 0)
			break;

	if (cand == NULL)
		return NULL;

	TAILQ_REMOVE(&fio->res_qing, cand, pfb_entries);
	return cand;
}

static void
moveinfo(struct puffs_framebuf *from, struct puffs_framebuf *to)
{

	assert(from->istat & ISTAT_INTERNAL);

	/* migrate buffer */
	free(to->buf);
	to->buf = from->buf;
	from->buf = NULL;

	/* migrate buffer info */
	to->len = from->len;
	to->offset = from->offset;
	to->maxoff = from->maxoff;
}

void
puffs_framev_input(struct puffs_usermount *pu, struct puffs_framectrl *fctrl,
	struct puffs_fctrl_io *fio, struct puffs_putreq *ppr)
{
	struct puffs_framebuf *pufbuf, *appbuf;
	int rv, complete;

	if (fio->stat & FIO_DEAD)
		return;

	for (;;) {
		if ((pufbuf = fio->cur_in) == NULL) {
			pufbuf = puffs_framebuf_make();
			if (pufbuf == NULL)
				return;
			pufbuf->istat |= ISTAT_INTERNAL;
			fio->cur_in = pufbuf;
		}

		complete = 0;
		rv = fctrl->rfb(pu, pufbuf, fio->io_fd, &complete);

		/* error */
		if (rv) {
			puffs_framev_readclose(pu, fio, rv);
			return;
		}

		/* partial read, come back to fight another day */
		if (complete == 0)
			break;

		/* else: full read, process */

		appbuf = findbuf(pu, fctrl, fio, pufbuf);

		/* XXX: error delivery? */
		if (appbuf == NULL) {
			/* errno = ENOMSG; */
			return;
		}
			
		appbuf->istat &= ~ISTAT_NODESTROY;
		moveinfo(pufbuf, appbuf);
		if (appbuf->pcc) {
			puffs_docc(appbuf->pcc, ppr);
		} else if (appbuf->fcb) {
			appbuf->fcb(pu, appbuf, appbuf->fcb_arg, 0);
		} else {
			puffs_framebuf_destroy(appbuf);
		}
		puffs_framebuf_destroy(pufbuf);

		/* hopeless romantics, here we go again */
		fio->cur_in = NULL;
	}
}

int
puffs_framev_output(struct puffs_usermount *pu, struct puffs_framectrl *fctrl,
	struct puffs_fctrl_io *fio)
{
	struct puffs_framebuf *pufbuf, *pufbuf_next;
	int rv, complete, error;

	if (fio->stat & FIO_DEAD)
		return 0;

	for (pufbuf = TAILQ_FIRST(&fio->snd_qing), error = 0;
	    pufbuf;
	    pufbuf = pufbuf_next) {
		complete = 0;
		pufbuf_next = TAILQ_NEXT(pufbuf, pfb_entries);
		rv = fctrl->wfb(pu, pufbuf, fio->io_fd, &complete);

		if (rv) {
			puffs_framev_writeclose(pu, fio, rv);
			error = 1;
			break;
		}

		/* partial write */
		if (complete == 0)
			return error;

		/* else, complete write */
		TAILQ_REMOVE(&fio->snd_qing, pufbuf, pfb_entries);

		/* can't wait for result if we can't read */
		if (fio->stat & FIO_RDGONE) {
			errnotify(pufbuf, ENXIO);
			error = 1;

		} else  if ((pufbuf->istat & ISTAT_NOREPLY) == 0) {
			TAILQ_INSERT_TAIL(&fio->res_qing, pufbuf,
			    pfb_entries);
		} else {
			pufbuf->istat &= ~ISTAT_NODESTROY;
			puffs_framebuf_destroy(pufbuf);
		}

		/* omstart! */
	}

	return error;
}

int
puffs_framev_addfd(struct puffs_usermount *pu, int fd)
{
	struct puffs_framectrl *pfctrl = &pu->pu_framectrl;
	struct puffs_fctrl_io *fio;
	struct kevent kev[2];
	struct kevent *newevs;
	size_t nfds;
	int rv;

	nfds = pfctrl->nfds+1;
	newevs = realloc(pfctrl->evs, (2*nfds+1) * sizeof(struct kevent));
	if (newevs == NULL)
		return -1;
	pfctrl->evs = newevs;

	fio = malloc(sizeof(struct puffs_fctrl_io));
	if (fio == NULL)
		return -1;

	if (pu->pu_state & PU_INLOOP) {
		EV_SET(&kev[0], fd, EVFILT_READ, EV_ADD, 0, 0, (intptr_t)fio);
		EV_SET(&kev[1], fd, EVFILT_WRITE, EV_ADD|EV_DISABLE,
		    0, 0, (intptr_t)fio);
		rv = kevent(pu->pu_kq, kev, 2, NULL, 0, NULL);
		if (rv == -1) {
			free(fio);
			return -1;
		}
	}

	fio->io_fd = fd;
	fio->cur_in = NULL;
	fio->stat = 0;
	TAILQ_INIT(&fio->snd_qing);
	TAILQ_INIT(&fio->res_qing);

	LIST_INSERT_HEAD(&pfctrl->fb_ios, fio, fio_entries);
	pfctrl->nfds = nfds;

	return 0;
}

void
puffs_framev_readclose(struct puffs_usermount *pu,
	struct puffs_fctrl_io *fio, int error)
{
	struct puffs_framebuf *pufbuf;
	struct kevent kev;
	int notflag;

	if (fio->stat & FIO_RDGONE || fio->stat & FIO_DEAD)
		return;
	fio->stat |= FIO_RDGONE;

	if (fio->cur_in) {
		puffs_framebuf_destroy(fio->cur_in);
		fio->cur_in = NULL;
	}

	while ((pufbuf = TAILQ_FIRST(&fio->res_qing)) != NULL) {
		TAILQ_REMOVE(&fio->res_qing, pufbuf, pfb_entries);
		errnotify(pufbuf, error);
	}

	EV_SET(&kev, fio->io_fd, EVFILT_READ, EV_DELETE, 0, 0, 0);
	(void) kevent(pu->pu_kq, &kev, 1, NULL, 0, NULL);

	notflag = PUFFS_FBGONE_READ;
	if (fio->stat & FIO_WRGONE)
		notflag |= PUFFS_FBGONE_WRITE;

	pu->pu_framectrl.fdnotfn(pu, fio->io_fd, notflag);
}

void
puffs_framev_writeclose(struct puffs_usermount *pu,
	struct puffs_fctrl_io *fio, int error)
{
	struct puffs_framebuf *pufbuf;
	struct kevent kev;
	int notflag;

	if (fio->stat & FIO_WRGONE || fio->stat & FIO_DEAD)
		return;
	fio->stat |= FIO_WRGONE;

	while ((pufbuf = TAILQ_FIRST(&fio->snd_qing)) != NULL) {
		TAILQ_REMOVE(&fio->snd_qing, pufbuf, pfb_entries);
		errnotify(pufbuf, error);
	}

	EV_SET(&kev, fio->io_fd, EVFILT_WRITE, EV_DELETE, 0, 0, 0);
	(void) kevent(pu->pu_kq, &kev, 1, NULL, 0, NULL);

	notflag = PUFFS_FBGONE_WRITE;
	if (fio->stat & FIO_RDGONE)
		notflag |= PUFFS_FBGONE_READ;

	pu->pu_framectrl.fdnotfn(pu, fio->io_fd, notflag);
}

static int
removefio(struct puffs_usermount *pu, struct puffs_fctrl_io *fio, int error)
{
	struct puffs_framectrl *pfctrl = &pu->pu_framectrl;

	LIST_REMOVE(fio, fio_entries);
	if (pu->pu_state & PU_INLOOP) {
		puffs_framev_readclose(pu, fio, error);
		puffs_framev_writeclose(pu, fio, error);
	}

	/* don't bother with realloc */
	pfctrl->nfds--;

	/* don't free us yet, might have some references in event arrays */
	fio->stat |= FIO_DEAD;
	LIST_INSERT_HEAD(&pfctrl->fb_ios_rmlist, fio, fio_entries);

	return 0;

}

int
puffs_framev_removefd(struct puffs_usermount *pu, int fd, int error)
{
	struct puffs_fctrl_io *fio;

	fio = getfiobyfd(pu, fd);
	if (fio == NULL) {
		errno = ENXIO;
		return -1;
	}

	return removefio(pu, fio, error ? error : ECONNRESET);
}

static void
defaultnot(struct puffs_usermount *pu, int fd, int what)
{

	if (PUFFS_FBGONE_BOTH(what))
		(void) puffs_framev_removefd(pu, fd, ECONNRESET);
}

void
puffs_framev_unmountonclose(struct puffs_usermount *pu, int fd, int what)
{

	/* XXX & X: unmount is non-sensible */
	defaultnot(pu, fd, what);
	if (PUFFS_FBGONE_BOTH(what))
		PU_SETSTATE(pu, PUFFS_STATE_UNMOUNTED);
}

void
puffs_framev_init(struct puffs_usermount *pu,
	puffs_framev_readframe_fn rfb, puffs_framev_writeframe_fn wfb,
	puffs_framev_cmpframe_fn cmpfb, puffs_framev_fdnotify_fn fdnotfn)
{
	struct puffs_framectrl *pfctrl;

	pfctrl = &pu->pu_framectrl;
	pfctrl->rfb = rfb;
	pfctrl->wfb = wfb;
	pfctrl->cmpfb = cmpfb;
	if (fdnotfn)
		pfctrl->fdnotfn = fdnotfn;
	else
		pfctrl->fdnotfn = defaultnot;
}

void
puffs_framev_exit(struct puffs_usermount *pu)
{
	struct puffs_framectrl *pfctrl = &pu->pu_framectrl;
	struct puffs_fctrl_io *fio;

	while ((fio = LIST_FIRST(&pfctrl->fb_ios)) != NULL)
		removefio(pu, fio, ENXIO);
	free(pfctrl->evs);

	/* closing pu->pu_kq takes care of puffsfd */
}