[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;
    int thpos;
    time_t to;
    struct muth *th;
};

static int qfd = -1, fdln = 0;
static int exitstatus;
static struct blocker **fdlist;
static typedbuf(struct blocker *) timeheap;

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 void thraise(struct blocker *bl, int n)
{
    int p;
    
    while(n > 0) {
	p = (n - 1) >> 1;
	if(timeheap.b[p]->to <= bl->to)
	    break;
	timeheap.b[n] = timeheap.b[p];
	timeheap.b[n]->thpos = n;
	n = p;
    }
    timeheap.b[n] = bl;
    bl->thpos = n;
}

static void thlower(struct blocker *bl, int n)
{
    int c;
    
    while(1) {
	c = (n << 1) + 1;
	if(c >= timeheap.d)
	    break;
	if((c + 1 < timeheap.d) && (timeheap.b[c + 1]->to < timeheap.b[c]->to))
	    c = c + 1;
	if(timeheap.b[c]->to > bl->to)
	    break;
	timeheap.b[n] = timeheap.b[c];
	timeheap.b[n]->thpos = n;
	n = c;
    }
    timeheap.b[n] = bl;
    bl->thpos = n;
}

static void addtimeout(struct blocker *bl, time_t to)
{
    sizebuf(timeheap, ++timeheap.d);
    thraise(bl, timeheap.d - 1);
}

static void deltimeout(struct blocker *bl)
{
    int n;
    
    if(bl->thpos == timeheap.d - 1) {
	timeheap.d--;
	return;
    }
    n = bl->thpos;
    bl = timeheap.b[--timeheap.d];
    if((n > 0) && (timeheap.b[(n - 1) >> 1]->to > bl->to))
	thraise(bl, n);
    else
	thlower(bl, n);
}

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

static void remblock(struct blocker *bl)
{
    if(bl->to > 0)
	deltimeout(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;
    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) {
	now = time(NULL);
	toval = &(struct timespec){};
	if(timeheap.d == 0)
	    toval  = NULL;
	else if(timeheap.b[0]->to > now)
	    *toval = (struct timespec){.tv_sec = timeheap.b[0]->to - 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);
	while((timeheap.d > 0) && ((bl = timeheap.b[0])->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
ac612570 FT	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;
be8b78f7	40	int ev, rev, id;
f73d8624	41	int thpos;
ac612570 FT	42	time_t to;
	43	struct muth *th;
	44	};
	45
	46	static int qfd = -1, fdln = 0;
	47	static int exitstatus;
	48	static struct blocker **fdlist;
f73d8624	49	static typedbuf(struct blocker *) timeheap;
ac612570 FT	50
	51	static int regfd(struct blocker *bl)
	52	{
	53	struct blocker *o;
	54	int prev;
	55	struct kevent evd;
	56
	57	if(bl->fd >= fdln) {
	58	if(fdlist) {
	59	fdlist = srealloc(fdlist, sizeof(fdlist) (bl->fd + 1));
	60	memset(fdlist + fdln, 0, sizeof(fdlist) (bl->fd + 1 - fdln));
	61	fdln = bl->fd + 1;
	62	} else {
	63	fdlist = szmalloc(sizeof(fdlist) (fdln = (bl->fd + 1)));
	64	}
	65	}
	66	for(prev = 0, o = fdlist[bl->fd]; o; o = o->n2)
	67	prev \|= o->ev;
	68	if((bl->ev & EV_READ) && !(prev & EV_READ)) {
	69	evd = (struct kevent) {
	70	.flags = EV_ADD,
	71	.ident = bl->fd,
	72	.filter = EVFILT_READ,
	73	};
	74	if(kevent(qfd, &evd, 1, NULL, 0, NULL) < 0) {
	75	/* XXX?! Whatever to do, really? */
	76	flog(LOG_ERR, "kevent(EV_ADD, EVFILT_READ) on fd %i: %s", bl->fd, strerror(errno));
	77	return(-1);
	78	}
	79	}
	80	if((bl->ev & EV_WRITE) && !(prev & EV_WRITE)) {
	81	evd = (struct kevent) {
	82	.flags = EV_ADD,
	83	.ident = bl->fd,
	84	.filter = EVFILT_WRITE,
	85	};
	86	if(kevent(qfd, &evd, 1, NULL, 0, NULL) < 0) {
	87	/* XXX?! Whatever to do, really? */
	88	flog(LOG_ERR, "kevent(EV_ADD, EVFILT_WRITE) on fd %i: %s", bl->fd, strerror(errno));
	89	return(-1);
	90	}
	91	}
	92	bl->n2 = fdlist[bl->fd];
	93	bl->p2 = NULL;
	94	if(fdlist[bl->fd] != NULL)
	95	fdlist[bl->fd]->p2 = bl;
	96	fdlist[bl->fd] = bl;
	97	bl->reg = 1;
	98	return(0);
	99	}
	100
	101	static void remfd(struct blocker *bl)
	102	{
	103	struct blocker *o;
	104	struct kevent evd;
	105	int left;
	106
	107	if(!bl->reg)
	108	return;
	109	if(bl->n2)
	110	bl->n2->p2 = bl->p2;
	111	if(bl->p2)
	112	bl->p2->n2 = bl->n2;
	113	if(bl == fdlist[bl->fd])
114	fdlist[bl->fd] = bl->n2;
115	for(left = 0, o = fdlist[bl->fd]; o; o = o->n2)
116	left \|= o->ev;
117	if((bl->ev & EV_READ) && !(left & EV_READ)) {
118	evd = (struct kevent) {
119	.flags = EV_DELETE,
120	.ident = bl->fd,
121	.filter = EVFILT_READ,
122	};
123	if(kevent(qfd, &evd, 1, NULL, 0, NULL) < 0) {
124	/* XXX?! Whatever to do, really? */
125	flog(LOG_ERR, "kevent(EV_DELETE, EVFILT_READ) on fd %i: %s", bl->fd, strerror(errno));
126	}
127	}
128	if((bl->ev & EV_WRITE) && !(left & EV_WRITE)) {
129	evd = (struct kevent) {
130	.flags = EV_DELETE,
131	.ident = bl->fd,
132	.filter = EVFILT_WRITE,
133	};
134	if(kevent(qfd, &evd, 1, NULL, 0, NULL) < 0) {
135	/* XXX?! Whatever to do, really? */
136	flog(LOG_ERR, "kevent(EV_DELETE, EVFILT_WRITE) on fd %i: %s", bl->fd, strerror(errno));
137	}
138	}
139	bl->reg = 0;
140	}
141
f73d8624 FT	142	static void thraise(struct blocker *bl, int n)
	143	{
	144	int p;
	145
	146	while(n > 0) {
	147	p = (n - 1) >> 1;
	148	if(timeheap.b[p]->to <= bl->to)
	149	break;
	150	timeheap.b[n] = timeheap.b[p];
	151	timeheap.b[n]->thpos = n;
	152	n = p;
	153	}
	154	timeheap.b[n] = bl;
	155	bl->thpos = n;
	156	}
	157
	158	static void thlower(struct blocker *bl, int n)
	159	{
	160	int c;
	161
	162	while(1) {
	163	c = (n << 1) + 1;
	164	if(c >= timeheap.d)
	165	break;
	166	if((c + 1 < timeheap.d) && (timeheap.b[c + 1]->to < timeheap.b[c]->to))
	167	c = c + 1;
	168	if(timeheap.b[c]->to > bl->to)
	169	break;
	170	timeheap.b[n] = timeheap.b[c];
	171	timeheap.b[n]->thpos = n;
	172	n = c;
	173	}
	174	timeheap.b[n] = bl;
	175	bl->thpos = n;
	176	}
	177
	178	static void addtimeout(struct blocker *bl, time_t to)
	179	{
	180	sizebuf(timeheap, ++timeheap.d);
	181	thraise(bl, timeheap.d - 1);
	182	}
	183
	184	static void deltimeout(struct blocker *bl)
	185	{
	186	int n;
	187
	188	if(bl->thpos == timeheap.d - 1) {
	189	timeheap.d--;
	190	return;
	191	}
	192	n = bl->thpos;
	193	bl = timeheap.b[--timeheap.d];
	194	if((n > 0) && (timeheap.b[(n - 1) >> 1]->to > bl->to))
	195	thraise(bl, n);
	196	else
	197	thlower(bl, n);
	198	}
	199
be8b78f7	200	static int addblock(struct blocker *bl)
ac612570	201	{
be8b78f7	202	if((qfd >= 0) && regfd(bl))
ac612570	203	return(-1);
ac612570 FT	204	bl->n = blockers;
	205	if(blockers)
	206	blockers->p = bl;
	207	blockers = bl;
f73d8624 FT	208	if(bl->to > 0)
f73d8624 FT	209	addtimeout(bl, bl->to);
be8b78f7 FT	210	return(0);
	211	}
	212
	213	static void remblock(struct blocker *bl)
	214	{
f73d8624 FT	215	if(bl->to > 0)
f73d8624 FT	216	deltimeout(bl);
ac612570 FT	217	if(bl->n)
	218	bl->n->p = bl->p;
	219	if(bl->p)
	220	bl->p->n = bl->n;
	221	if(bl == blockers)
	222	blockers = bl->n;
	223	remfd(bl);
be8b78f7 FT	224	}
	225
	226	struct selected mblock(time_t to, int n, struct selected *spec)
	227	{
	228	int i, id;
	229	struct blocker bls[n];
	230
	231	to = (to > 0)?(time(NULL) + to):0;
	232	for(i = 0; i < n; i++) {
	233	bls[i] = (struct blocker) {
	234	.fd = spec[i].fd,
	235	.ev = spec[i].ev,
	236	.id = i,
	237	.to = to,
	238	.th = current,
	239	};
	240	if(addblock(&bls[i])) {
	241	for(i--; i >= 0; i--)
	242	remblock(&bls[i]);
	243	return((struct selected){.fd = -1, .ev = -1});
	244	}
	245	}
	246	id = yield();
	247	for(i = 0; i < n; i++)
	248	remblock(&bls[i]);
	249	if(id < 0)
	250	return((struct selected){.fd = -1, .ev = -1});
	251	return((struct selected){.fd = bls[id].fd, .ev = bls[id].rev});
	252	}
	253
	254	int block(int fd, int ev, time_t to)
	255	{
	256	struct blocker bl;
	257	int rv;
	258
	259	bl = (struct blocker) {
	260	.fd = fd,
	261	.ev = ev,
	262	.id = -1,
	263	.to = (to > 0)?(time(NULL) + to):0,
	264	.th = current,
	265	};
	266	addblock(&bl);
	267	rv = yield();
	268	remblock(&bl);
ac612570 FT	269	return(rv);
	270	}
	271
	272	int ioloop(void)
	273	{
	274	struct blocker bl, nbl;
	275	struct kevent evs[16];
	276	int i, fd, nev, ev;
f73d8624	277	time_t now;
ac612570 FT	278	struct timespec *toval;
	279
	280	exitstatus = 0;
	281	qfd = kqueue();
	282	fcntl(qfd, F_SETFD, FD_CLOEXEC);
	283	for(bl = blockers; bl; bl = nbl) {
	284	nbl = bl->n;
	285	if(regfd(bl))
	286	resume(bl->th, -1);
	287	}
	288	while(blockers != NULL) {
ac612570	289	now = time(NULL);
6f7dbebc	290	toval = &(struct timespec){};
f73d8624	291	if(timeheap.d == 0)
ac612570	292	toval = NULL;
f73d8624	293	else if(timeheap.b[0]->to > now)
6f7dbebc	294	*toval = (struct timespec){.tv_sec = timeheap.b[0]->to - now};
ac612570	295	else
6f7dbebc	296	*toval = (struct timespec){.tv_sec = 1};
ac612570 FT	297	if(exitstatus)
	298	break;
	299	nev = kevent(qfd, NULL, 0, evs, sizeof(evs) / sizeof(*evs), toval);
	300	if(nev < 0) {
	301	if(errno != EINTR) {
	302	flog(LOG_CRIT, "ioloop: kevent errored out: %s", strerror(errno));
	303	/* To avoid CPU hogging in case it's bad, which it
	304	* probably is. */
	305	sleep(1);
	306	}
	307	continue;
	308	}
	309	for(i = 0; i < nev; i++) {
	310	fd = (int)evs[i].ident;
	311	ev = (evs[i].filter == EVFILT_READ)?EV_READ:EV_WRITE;
	312	for(bl = fdlist[fd]; bl; bl = nbl) {
	313	nbl = bl->n2;
be8b78f7 FT	314	if(ev & bl->ev) {
	315	if(bl->id < 0) {
	316	resume(bl->th, ev);
	317	} else {
	318	bl->rev = ev;
	319	resume(bl->th, bl->id);
	320	}
	321	}
ac612570 FT	322	}
	323	}
	324	now = time(NULL);
f73d8624 FT	325	while((timeheap.d > 0) && ((bl = timeheap.b[0])->to <= now)) {
	326	if(bl->id < 0) {
	327	resume(bl->th, 0);
	328	} else {
	329	bl->rev = 0;
	330	resume(bl->th, bl->id);
be8b78f7	331	}
ac612570 FT	332	}
	333	}
	334	for(bl = blockers; bl; bl = bl->n)
	335	remfd(bl);
	336	close(qfd);
	337	qfd = -1;
	338	return(exitstatus);
	339	}
	340
	341	void exitioloop(int status)
	342	{
	343	exitstatus = status;
	344	}