[ashd.git] / lib / mtio-kqueue.c

/*
    ashd - A Sane HTTP Daemon
    Copyright (C) 2008  Fredrik Tolf <fredrik@dolda2000.com>

    This program is free software: you can redistribute it and/or modify
    it under the terms of the GNU General Public License as published by
    the Free Software Foundation, either version 3 of the License, or
    (at your option) any later version.

    This program is distributed in the hope that it will be useful,
    but WITHOUT ANY WARRANTY; without even the implied warranty of
    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
    GNU General Public License for more details.

    You should have received a copy of the GNU General Public License
    along with this program.  If not, see <http://www.gnu.org/licenses/>.
*/

#include <stdlib.h>
#include <unistd.h>
#include <time.h>
#include <fcntl.h>
#include <string.h>
#include <sys/event.h>
#include <errno.h>

#ifdef HAVE_CONFIG_H
#include <config.h>
#endif
#include <log.h>
#include <utils.h>
#include <mt.h>
#include <mtio.h>

static struct blocker *blockers;

struct blocker {
    struct blocker *n, *p, *n2, *p2;
    int fd, reg;
    int ev, rev, id;
    time_t to;
    struct muth *th;
};

static int qfd = -1, fdln = 0;
static int exitstatus;
static struct blocker **fdlist;

static int regfd(struct blocker *bl)
{
    struct blocker *o;
    int prev;
    struct kevent evd;
    
    if(bl->fd >= fdln) {
	if(fdlist) {
	    fdlist = srealloc(fdlist, sizeof(*fdlist) * (bl->fd + 1));
	    memset(fdlist + fdln, 0, sizeof(*fdlist) * (bl->fd + 1 - fdln));
	    fdln = bl->fd + 1;
	} else {
	    fdlist = szmalloc(sizeof(*fdlist) * (fdln = (bl->fd + 1)));
	}
    }
    for(prev = 0, o = fdlist[bl->fd]; o; o = o->n2)
	prev |= o->ev;
    if((bl->ev & EV_READ) && !(prev & EV_READ)) {
	evd = (struct kevent) {
	    .flags = EV_ADD,
	    .ident = bl->fd,
	    .filter = EVFILT_READ,
	};
	if(kevent(qfd, &evd, 1, NULL, 0, NULL) < 0) {
	    /* XXX?! Whatever to do, really? */
	    flog(LOG_ERR, "kevent(EV_ADD, EVFILT_READ) on fd %i: %s", bl->fd, strerror(errno));
	    return(-1);
	}
    }
    if((bl->ev & EV_WRITE) && !(prev & EV_WRITE)) {
	evd = (struct kevent) {
	    .flags = EV_ADD,
	    .ident = bl->fd,
	    .filter = EVFILT_WRITE,
	};
	if(kevent(qfd, &evd, 1, NULL, 0, NULL) < 0) {
	    /* XXX?! Whatever to do, really? */
	    flog(LOG_ERR, "kevent(EV_ADD, EVFILT_WRITE) on fd %i: %s", bl->fd, strerror(errno));
	    return(-1);
	}
    }
    bl->n2 = fdlist[bl->fd];
    bl->p2 = NULL;
    if(fdlist[bl->fd] != NULL)
	fdlist[bl->fd]->p2 = bl;
    fdlist[bl->fd] = bl;
    bl->reg = 1;
    return(0);
}

static void remfd(struct blocker *bl)
{
    struct blocker *o;
    struct kevent evd;
    int left;
    
    if(!bl->reg)
	return;
    if(bl->n2)
	bl->n2->p2 = bl->p2;
    if(bl->p2)
	bl->p2->n2 = bl->n2;
    if(bl == fdlist[bl->fd])
	fdlist[bl->fd] = bl->n2;
    for(left = 0, o = fdlist[bl->fd]; o; o = o->n2)
	left |= o->ev;
    if((bl->ev & EV_READ) && !(left & EV_READ)) {
	evd = (struct kevent) {
	    .flags = EV_DELETE,
	    .ident = bl->fd,
	    .filter = EVFILT_READ,
	};
	if(kevent(qfd, &evd, 1, NULL, 0, NULL) < 0) {
	    /* XXX?! Whatever to do, really? */
	    flog(LOG_ERR, "kevent(EV_DELETE, EVFILT_READ) on fd %i: %s", bl->fd, strerror(errno));
	}
    }
    if((bl->ev & EV_WRITE) && !(left & EV_WRITE)) {
	evd = (struct kevent) {
	    .flags = EV_DELETE,
	    .ident = bl->fd,
	    .filter = EVFILT_WRITE,
	};
	if(kevent(qfd, &evd, 1, NULL, 0, NULL) < 0) {
	    /* XXX?! Whatever to do, really? */
	    flog(LOG_ERR, "kevent(EV_DELETE, EVFILT_WRITE) on fd %i: %s", bl->fd, strerror(errno));
	}
    }
    bl->reg = 0;
}

static int addblock(struct blocker *bl)
{
    if((qfd >= 0) && regfd(bl))
	return(-1);
    bl->n = blockers;
    if(blockers)
	blockers->p = bl;
    blockers = bl;
    return(0);
}

static void remblock(struct blocker *bl)
{
    if(bl->n)
	bl->n->p = bl->p;
    if(bl->p)
	bl->p->n = bl->n;
    if(bl == blockers)
	blockers = bl->n;
    remfd(bl);
}

struct selected mblock(time_t to, int n, struct selected *spec)
{
    int i, id;
    struct blocker bls[n];
    
    to = (to > 0)?(time(NULL) + to):0;
    for(i = 0; i < n; i++) {
	bls[i] = (struct blocker) {
	    .fd = spec[i].fd,
	    .ev = spec[i].ev,
	    .id = i,
	    .to = to,
	    .th = current,
	};
	if(addblock(&bls[i])) {
	    for(i--; i >= 0; i--)
		remblock(&bls[i]);
	    return((struct selected){.fd = -1, .ev = -1});
	}
    }
    id = yield();
    for(i = 0; i < n; i++)
	remblock(&bls[i]);
    if(id < 0)
	return((struct selected){.fd = -1, .ev = -1});
    return((struct selected){.fd = bls[id].fd, .ev = bls[id].rev});
}

int block(int fd, int ev, time_t to)
{
    struct blocker bl;
    int rv;
    
    bl = (struct blocker) {
	.fd = fd,
	.ev = ev,
	.id = -1,
	.to = (to > 0)?(time(NULL) + to):0,
	.th = current,
    };
    addblock(&bl);
    rv = yield();
    remblock(&bl);
    return(rv);
}

int ioloop(void)
{
    struct blocker *bl, *nbl;
    struct kevent evs[16];
    int i, fd, nev, ev;
    time_t now, timeout;
    struct timespec *toval;
    
    exitstatus = 0;
    qfd = kqueue();
    fcntl(qfd, F_SETFD, FD_CLOEXEC);
    for(bl = blockers; bl; bl = nbl) {
	nbl = bl->n;
	if(regfd(bl))
	    resume(bl->th, -1);
    }
    while(blockers != NULL) {
	timeout = 0;
	for(bl = blockers; bl; bl = bl->n) {
	    if((bl->to != 0) && ((timeout == 0) || (timeout > bl->to)))
		timeout = bl->to;
	}
	now = time(NULL);
	if(timeout == 0)
	    toval  = NULL;
	else if(timeout > now)
	    toval = &(struct timespec){.tv_sec = timeout - now};
	else
	    toval = &(struct timespec){.tv_sec = 1};
	if(exitstatus)
	    break;
	nev = kevent(qfd, NULL, 0, evs, sizeof(evs) / sizeof(*evs), toval);
	if(nev < 0) {
	    if(errno != EINTR) {
		flog(LOG_CRIT, "ioloop: kevent errored out: %s", strerror(errno));
		/* To avoid CPU hogging in case it's bad, which it
		 * probably is. */
		sleep(1);
	    }
	    continue;
	}
	for(i = 0; i < nev; i++) {
	    fd = (int)evs[i].ident;
	    ev = (evs[i].filter == EVFILT_READ)?EV_READ:EV_WRITE;
	    for(bl = fdlist[fd]; bl; bl = nbl) {
		nbl = bl->n2;
		if(ev & bl->ev) {
		    if(bl->id < 0) {
			resume(bl->th, ev);
		    } else {
			bl->rev = ev;
			resume(bl->th, bl->id);
		    }
		}
	    }
	}
	now = time(NULL);
	for(bl = blockers; bl; bl = nbl) {
	    nbl = bl->n;
	    if((bl->to != 0) && (bl->to <= now)) {
		if(bl->id < 0) {
		    resume(bl->th, 0);
		} else {
		    bl->rev = 0;
		    resume(bl->th, bl->id);
		}
	    }
	}
    }
    for(bl = blockers; bl; bl = bl->n)
	remfd(bl);
    close(qfd);
    qfd = -1;
    return(exitstatus);
}

void exitioloop(int status)
{
    exitstatus = status;
}
Commit	Line	Data
	1	/*
	2	ashd - A Sane HTTP Daemon
	3	Copyright (C) 2008 Fredrik Tolf <fredrik@dolda2000.com>
	4
	5	This program is free software: you can redistribute it and/or modify
	6	it under the terms of the GNU General Public License as published by
	7	the Free Software Foundation, either version 3 of the License, or
	8	(at your option) any later version.
	9
	10	This program is distributed in the hope that it will be useful,
	11	but WITHOUT ANY WARRANTY; without even the implied warranty of
	12	MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
	13	GNU General Public License for more details.
	14
	15	You should have received a copy of the GNU General Public License
	16	along with this program. If not, see <http://www.gnu.org/licenses/>.
	17	*/
	18
	19	#include <stdlib.h>
	20	#include <unistd.h>
	21	#include <time.h>
	22	#include <fcntl.h>
	23	#include <string.h>
	24	#include <sys/event.h>
	25	#include <errno.h>
	26
	27	#ifdef HAVE_CONFIG_H
	28	#include <config.h>
	29	#endif
	30	#include <log.h>
	31	#include <utils.h>
	32	#include <mt.h>
	33	#include <mtio.h>
	34
	35	static struct blocker *blockers;
	36
	37	struct blocker {
	38	struct blocker n, p, n2, p2;
	39	int fd, reg;
	40	int ev, rev, id;
	41	time_t to;
	42	struct muth *th;
	43	};
	44
	45	static int qfd = -1, fdln = 0;
	46	static int exitstatus;
	47	static struct blocker **fdlist;
	48
	49	static int regfd(struct blocker *bl)
	50	{
	51	struct blocker *o;
	52	int prev;
	53	struct kevent evd;
	54
	55	if(bl->fd >= fdln) {
	56	if(fdlist) {
	57	fdlist = srealloc(fdlist, sizeof(fdlist) (bl->fd + 1));
	58	memset(fdlist + fdln, 0, sizeof(fdlist) (bl->fd + 1 - fdln));
	59	fdln = bl->fd + 1;
	60	} else {
	61	fdlist = szmalloc(sizeof(fdlist) (fdln = (bl->fd + 1)));
	62	}
	63	}
	64	for(prev = 0, o = fdlist[bl->fd]; o; o = o->n2)
	65	prev \|= o->ev;
	66	if((bl->ev & EV_READ) && !(prev & EV_READ)) {
	67	evd = (struct kevent) {
	68	.flags = EV_ADD,
	69	.ident = bl->fd,
	70	.filter = EVFILT_READ,
	71	};
	72	if(kevent(qfd, &evd, 1, NULL, 0, NULL) < 0) {
	73	/* XXX?! Whatever to do, really? */
	74	flog(LOG_ERR, "kevent(EV_ADD, EVFILT_READ) on fd %i: %s", bl->fd, strerror(errno));
	75	return(-1);
	76	}
	77	}
	78	if((bl->ev & EV_WRITE) && !(prev & EV_WRITE)) {
	79	evd = (struct kevent) {
	80	.flags = EV_ADD,
	81	.ident = bl->fd,
	82	.filter = EVFILT_WRITE,
	83	};
	84	if(kevent(qfd, &evd, 1, NULL, 0, NULL) < 0) {
	85	/* XXX?! Whatever to do, really? */
	86	flog(LOG_ERR, "kevent(EV_ADD, EVFILT_WRITE) on fd %i: %s", bl->fd, strerror(errno));
	87	return(-1);
	88	}
	89	}
	90	bl->n2 = fdlist[bl->fd];
	91	bl->p2 = NULL;
	92	if(fdlist[bl->fd] != NULL)
	93	fdlist[bl->fd]->p2 = bl;
	94	fdlist[bl->fd] = bl;
	95	bl->reg = 1;
	96	return(0);
	97	}
	98
	99	static void remfd(struct blocker *bl)
	100	{
	101	struct blocker *o;
	102	struct kevent evd;
	103	int left;
	104
	105	if(!bl->reg)
	106	return;
	107	if(bl->n2)
	108	bl->n2->p2 = bl->p2;
	109	if(bl->p2)
	110	bl->p2->n2 = bl->n2;
	111	if(bl == fdlist[bl->fd])
	112	fdlist[bl->fd] = bl->n2;
	113	for(left = 0, o = fdlist[bl->fd]; o; o = o->n2)
	114	left \|= o->ev;
	115	if((bl->ev & EV_READ) && !(left & EV_READ)) {
	116	evd = (struct kevent) {
	117	.flags = EV_DELETE,
	118	.ident = bl->fd,
	119	.filter = EVFILT_READ,
	120	};
	121	if(kevent(qfd, &evd, 1, NULL, 0, NULL) < 0) {
	122	/* XXX?! Whatever to do, really? */
	123	flog(LOG_ERR, "kevent(EV_DELETE, EVFILT_READ) on fd %i: %s", bl->fd, strerror(errno));
	124	}
	125	}
	126	if((bl->ev & EV_WRITE) && !(left & EV_WRITE)) {
	127	evd = (struct kevent) {
	128	.flags = EV_DELETE,
	129	.ident = bl->fd,
	130	.filter = EVFILT_WRITE,
	131	};
	132	if(kevent(qfd, &evd, 1, NULL, 0, NULL) < 0) {
	133	/* XXX?! Whatever to do, really? */
	134	flog(LOG_ERR, "kevent(EV_DELETE, EVFILT_WRITE) on fd %i: %s", bl->fd, strerror(errno));
	135	}
	136	}
	137	bl->reg = 0;
	138	}
	139
	140	static int addblock(struct blocker *bl)
	141	{
	142	if((qfd >= 0) && regfd(bl))
	143	return(-1);
	144	bl->n = blockers;
	145	if(blockers)
	146	blockers->p = bl;
	147	blockers = bl;
	148	return(0);
	149	}
	150
	151	static void remblock(struct blocker *bl)
	152	{
	153	if(bl->n)
	154	bl->n->p = bl->p;
	155	if(bl->p)
	156	bl->p->n = bl->n;
	157	if(bl == blockers)
	158	blockers = bl->n;
	159	remfd(bl);
	160	}
	161
	162	struct selected mblock(time_t to, int n, struct selected *spec)
	163	{
	164	int i, id;
	165	struct blocker bls[n];
	166
	167	to = (to > 0)?(time(NULL) + to):0;
	168	for(i = 0; i < n; i++) {
	169	bls[i] = (struct blocker) {
	170	.fd = spec[i].fd,
	171	.ev = spec[i].ev,
	172	.id = i,
	173	.to = to,
	174	.th = current,
	175	};
	176	if(addblock(&bls[i])) {
	177	for(i--; i >= 0; i--)
	178	remblock(&bls[i]);
	179	return((struct selected){.fd = -1, .ev = -1});
	180	}
	181	}
	182	id = yield();
	183	for(i = 0; i < n; i++)
	184	remblock(&bls[i]);
	185	if(id < 0)
	186	return((struct selected){.fd = -1, .ev = -1});
	187	return((struct selected){.fd = bls[id].fd, .ev = bls[id].rev});
	188	}
	189
	190	int block(int fd, int ev, time_t to)
	191	{
	192	struct blocker bl;
	193	int rv;
	194
	195	bl = (struct blocker) {
	196	.fd = fd,
	197	.ev = ev,
	198	.id = -1,
	199	.to = (to > 0)?(time(NULL) + to):0,
	200	.th = current,
	201	};
	202	addblock(&bl);
	203	rv = yield();
	204	remblock(&bl);
	205	return(rv);
	206	}
	207
	208	int ioloop(void)
	209	{
	210	struct blocker bl, nbl;
	211	struct kevent evs[16];
	212	int i, fd, nev, ev;
	213	time_t now, timeout;
	214	struct timespec *toval;
	215
	216	exitstatus = 0;
	217	qfd = kqueue();
	218	fcntl(qfd, F_SETFD, FD_CLOEXEC);
	219	for(bl = blockers; bl; bl = nbl) {
	220	nbl = bl->n;
	221	if(regfd(bl))
	222	resume(bl->th, -1);
	223	}
	224	while(blockers != NULL) {
	225	timeout = 0;
	226	for(bl = blockers; bl; bl = bl->n) {
	227	if((bl->to != 0) && ((timeout == 0) \|\| (timeout > bl->to)))
	228	timeout = bl->to;
	229	}
	230	now = time(NULL);
	231	if(timeout == 0)
	232	toval = NULL;
	233	else if(timeout > now)
	234	toval = &(struct timespec){.tv_sec = timeout - now};
	235	else
	236	toval = &(struct timespec){.tv_sec = 1};
	237	if(exitstatus)
	238	break;
	239	nev = kevent(qfd, NULL, 0, evs, sizeof(evs) / sizeof(*evs), toval);
	240	if(nev < 0) {
	241	if(errno != EINTR) {
	242	flog(LOG_CRIT, "ioloop: kevent errored out: %s", strerror(errno));
	243	/* To avoid CPU hogging in case it's bad, which it
	244	* probably is. */
	245	sleep(1);
	246	}
	247	continue;
	248	}
	249	for(i = 0; i < nev; i++) {
	250	fd = (int)evs[i].ident;
	251	ev = (evs[i].filter == EVFILT_READ)?EV_READ:EV_WRITE;
	252	for(bl = fdlist[fd]; bl; bl = nbl) {
	253	nbl = bl->n2;
	254	if(ev & bl->ev) {
	255	if(bl->id < 0) {
	256	resume(bl->th, ev);
	257	} else {
	258	bl->rev = ev;
	259	resume(bl->th, bl->id);
	260	}
	261	}
	262	}
	263	}
	264	now = time(NULL);
	265	for(bl = blockers; bl; bl = nbl) {
	266	nbl = bl->n;
	267	if((bl->to != 0) && (bl->to <= now)) {
	268	if(bl->id < 0) {
	269	resume(bl->th, 0);
	270	} else {
	271	bl->rev = 0;
	272	resume(bl->th, bl->id);
	273	}
	274	}
	275	}
	276	}
	277	for(bl = blockers; bl; bl = bl->n)
	278	remfd(bl);
	279	close(qfd);
	280	qfd = -1;
	281	return(exitstatus);
	282	}
	283
	284	void exitioloop(int status)
	285	{
	286	exitstatus = status;
	287	}