[ashd.git] / lib / mtio-epoll.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/epoll.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 epfd = -1, fdln = 0;
static int exitstatus;
static struct blocker **fdlist;

static int regfd(struct blocker *bl)
{
    struct blocker *o;
    struct epoll_event evd;
    
    memset(&evd, 0, sizeof(evd));
    evd.events = 0;
    if(bl->ev & EV_READ)
	evd.events |= EPOLLIN;
    if(bl->ev & EV_WRITE)
	evd.events |= EPOLLOUT;
    evd.data.fd = bl->fd;
    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)));
	}
    }
    if(fdlist[bl->fd] == NULL) {
	if(epoll_ctl(epfd, EPOLL_CTL_ADD, bl->fd, &evd)) {
	    /* XXX?! Whatever to do, really? */
	    flog(LOG_ERR, "epoll_add on fd %i: %s", bl->fd, strerror(errno));
	    return(-1);
	}
    } else {
	for(o = fdlist[bl->fd]; o; o = o->n2) {
	    if(o->ev & EV_READ)
		evd.events |= EPOLLIN;
	    if(o->ev & EV_WRITE)
		evd.events |= EPOLLOUT;
	}
	if(epoll_ctl(epfd, EPOLL_CTL_MOD, bl->fd, &evd)) {
	    /* XXX?! Whatever to do, really? */
	    flog(LOG_ERR, "epoll_mod 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 epoll_event evd;
    
    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;
    if(fdlist[bl->fd] == NULL) {
	if(epoll_ctl(epfd, EPOLL_CTL_DEL, bl->fd, NULL))
	    flog(LOG_ERR, "epoll_del on fd %i: %s", bl->fd, strerror(errno));
    } else {
	memset(&evd, 0, sizeof(evd));
	evd.events = 0;
	evd.data.fd = bl->fd;
	for(o = fdlist[bl->fd]; o; o = o->n2) {
	    if(o->ev & EV_READ)
		evd.events |= EPOLLIN;
	    if(o->ev & EV_WRITE)
		evd.events |= EPOLLOUT;
	}
	if(epoll_ctl(epfd, EPOLL_CTL_MOD, bl->fd, &evd)) {
	    /* XXX?! Whatever to do, really? */
	    flog(LOG_ERR, "epoll_mod on fd %i: %s", bl->fd, strerror(errno));
	}
    }
    bl->reg = 0;
}

static int addblock(struct blocker *bl)
{
    if((epfd >= 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(blockers == bl)
	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,
    };
    if(addblock(&bl))
	return(-1);
    rv = yield();
    remblock(&bl);
    return(rv);
}

int ioloop(void)
{
    struct blocker *bl, *nbl;
    struct epoll_event evr[16];
    int i, fd, nev, ev, toval;
    time_t now, timeout;
    
    exitstatus = 0;
    epfd = epoll_create(128);
    fcntl(epfd, 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 = -1;
	else if(timeout > now)
	    toval = (timeout - now) * 1000;
	else
	    toval = 1000;
	if(exitstatus)
	    break;
	nev = epoll_wait(epfd, evr, sizeof(evr) / sizeof(*evr), toval);
	if(nev < 0) {
	    if(errno != EINTR) {
		flog(LOG_CRIT, "ioloop: epoll_wait 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 = evr[i].data.fd;
	    ev = 0;
	    if(evr[i].events & EPOLLIN)
		ev |= EV_READ;
	    if(evr[i].events & EPOLLOUT)
		ev |= EV_WRITE;
	    if(evr[i].events & ~(EPOLLIN | EPOLLOUT))
		ev = -1;
	    for(bl = fdlist[fd]; bl; bl = nbl) {
		nbl = bl->n2;
		if((ev < 0) || (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(epfd);
    epfd = -1;
    return(exitstatus);
}

void exitioloop(int status)
{
    exitstatus = status;
}
Commit	Line	Data
a6cda4dd 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>
4f6d772e FT	20	#include <unistd.h>
4f6d772e FT	21	#include <time.h>
be078ac9	22	#include <fcntl.h>
a6cda4dd FT	23	#include <string.h>
	24	#include <sys/epoll.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;
205ee933	40	int ev, rev, id;
a6cda4dd FT	41	time_t to;
	42	struct muth *th;
	43	};
	44
	45	static int epfd = -1, fdln = 0;
9d32586e	46	static int exitstatus;
a6cda4dd FT	47	static struct blocker **fdlist;
	48
	49	static int regfd(struct blocker *bl)
	50	{
	51	struct blocker *o;
	52	struct epoll_event evd;
	53
	54	memset(&evd, 0, sizeof(evd));
	55	evd.events = 0;
	56	if(bl->ev & EV_READ)
	57	evd.events \|= EPOLLIN;
	58	if(bl->ev & EV_WRITE)
	59	evd.events \|= EPOLLOUT;
	60	evd.data.fd = bl->fd;
	61	if(bl->fd >= fdln) {
	62	if(fdlist) {
	63	fdlist = srealloc(fdlist, sizeof(fdlist) (bl->fd + 1));
	64	memset(fdlist + fdln, 0, sizeof(fdlist) (bl->fd + 1 - fdln));
	65	fdln = bl->fd + 1;
	66	} else {
	67	fdlist = szmalloc(sizeof(fdlist) (fdln = (bl->fd + 1)));
	68	}
	69	}
	70	if(fdlist[bl->fd] == NULL) {
	71	if(epoll_ctl(epfd, EPOLL_CTL_ADD, bl->fd, &evd)) {
	72	/* XXX?! Whatever to do, really? */
	73	flog(LOG_ERR, "epoll_add on fd %i: %s", bl->fd, strerror(errno));
	74	return(-1);
	75	}
	76	} else {
	77	for(o = fdlist[bl->fd]; o; o = o->n2) {
	78	if(o->ev & EV_READ)
	79	evd.events \|= EPOLLIN;
	80	if(o->ev & EV_WRITE)
	81	evd.events \|= EPOLLOUT;
	82	}
	83	if(epoll_ctl(epfd, EPOLL_CTL_MOD, bl->fd, &evd)) {
	84	/* XXX?! Whatever to do, really? */
	85	flog(LOG_ERR, "epoll_mod on fd %i: %s", bl->fd, strerror(errno));
	86	return(-1);
	87	}
	88	}
	89	bl->n2 = fdlist[bl->fd];
	90	bl->p2 = NULL;
	91	if(fdlist[bl->fd] != NULL)
	92	fdlist[bl->fd]->p2 = bl;
	93	fdlist[bl->fd] = bl;
	94	bl->reg = 1;
	95	return(0);
	96	}
	97
	98	static void remfd(struct blocker *bl)
	99	{
	100	struct blocker *o;
	101	struct epoll_event evd;
	102
	103	if(!bl->reg)
	104	return;
	105	if(bl->n2)
	106	bl->n2->p2 = bl->p2;
	107	if(bl->p2)
	108	bl->p2->n2 = bl->n2;
	109	if(bl == fdlist[bl->fd])
	110	fdlist[bl->fd] = bl->n2;
111	if(fdlist[bl->fd] == NULL) {
112	if(epoll_ctl(epfd, EPOLL_CTL_DEL, bl->fd, NULL))
113	flog(LOG_ERR, "epoll_del on fd %i: %s", bl->fd, strerror(errno));
114	} else {
115	memset(&evd, 0, sizeof(evd));
116	evd.events = 0;
117	evd.data.fd = bl->fd;
118	for(o = fdlist[bl->fd]; o; o = o->n2) {
119	if(o->ev & EV_READ)
120	evd.events \|= EPOLLIN;
121	if(o->ev & EV_WRITE)
122	evd.events \|= EPOLLOUT;
123	}
124	if(epoll_ctl(epfd, EPOLL_CTL_MOD, bl->fd, &evd)) {
125	/* XXX?! Whatever to do, really? */
126	flog(LOG_ERR, "epoll_mod on fd %i: %s", bl->fd, strerror(errno));
127	}
128	}
9d32586e	129	bl->reg = 0;
a6cda4dd FT	130	}
a6cda4dd FT	131
205ee933	132	static int addblock(struct blocker *bl)
a6cda4dd	133	{
205ee933	134	if((epfd >= 0) && regfd(bl))
a6cda4dd	135	return(-1);
a6cda4dd FT	136	bl->n = blockers;
	137	if(blockers)
	138	blockers->p = bl;
	139	blockers = bl;
205ee933 FT	140	return(0);
	141	}
	142
	143	static void remblock(struct blocker *bl)
	144	{
a6cda4dd FT	145	if(bl->n)
	146	bl->n->p = bl->p;
	147	if(bl->p)
	148	bl->p->n = bl->n;
205ee933	149	if(blockers == bl)
a6cda4dd FT	150	blockers = bl->n;
a6cda4dd FT	151	remfd(bl);
205ee933 FT	152	}
	153
	154	struct selected mblock(time_t to, int n, struct selected *spec)
	155	{
	156	int i, id;
	157	struct blocker bls[n];
	158
	159	to = (to > 0)?(time(NULL) + to):0;
	160	for(i = 0; i < n; i++) {
	161	bls[i] = (struct blocker) {
	162	.fd = spec[i].fd,
	163	.ev = spec[i].ev,
	164	.id = i,
	165	.to = to,
	166	.th = current,
	167	};
	168	if(addblock(&bls[i])) {
	169	for(i--; i >= 0; i++)
	170	remblock(&bls[i]);
	171	return((struct selected){.fd = -1, .ev = -1});
	172	}
	173	}
	174	id = yield();
	175	for(i = 0; i < n; i++)
	176	remblock(&bls[i]);
	177	if(id < 0)
	178	return((struct selected){.fd = -1, .ev = -1});
	179	return((struct selected){.fd = bls[id].fd, .ev = bls[id].rev});
	180	}
	181
	182	int block(int fd, int ev, time_t to)
	183	{
	184	struct blocker bl;
	185	int rv;
	186
	187	bl = (struct blocker) {
	188	.fd = fd,
	189	.ev = ev,
	190	.id = -1,
	191	.to = (to > 0)?(time(NULL) + to):0,
	192	.th = current,
	193	};
	194	if(addblock(&bl))
	195	return(-1);
	196	rv = yield();
	197	remblock(&bl);
a6cda4dd FT	198	return(rv);
	199	}
	200
9d32586e	201	int ioloop(void)
a6cda4dd FT	202	{
	203	struct blocker bl, nbl;
	204	struct epoll_event evr[16];
	205	int i, fd, nev, ev, toval;
	206	time_t now, timeout;
	207
9d32586e	208	exitstatus = 0;
a6cda4dd	209	epfd = epoll_create(128);
be078ac9	210	fcntl(epfd, F_SETFD, FD_CLOEXEC);
a6cda4dd FT	211	for(bl = blockers; bl; bl = nbl) {
	212	nbl = bl->n;
	213	if(regfd(bl))
	214	resume(bl->th, -1);
	215	}
	216	while(blockers != NULL) {
	217	timeout = 0;
	218	for(bl = blockers; bl; bl = bl->n) {
	219	if((bl->to != 0) && ((timeout == 0) \|\| (timeout > bl->to)))
	220	timeout = bl->to;
	221	}
	222	now = time(NULL);
	223	if(timeout == 0)
	224	toval = -1;
	225	else if(timeout > now)
	226	toval = (timeout - now) * 1000;
	227	else
	228	toval = 1000;
9d32586e FT	229	if(exitstatus)
9d32586e FT	230	break;
a6cda4dd FT	231	nev = epoll_wait(epfd, evr, sizeof(evr) / sizeof(*evr), toval);
	232	if(nev < 0) {
	233	if(errno != EINTR) {
f43decce	234	flog(LOG_CRIT, "ioloop: epoll_wait errored out: %s", strerror(errno));
a6cda4dd FT	235	/* To avoid CPU hogging in case it's bad, which it
	236	* probably is. */
	237	sleep(1);
	238	}
	239	continue;
	240	}
	241	for(i = 0; i < nev; i++) {
	242	fd = evr[i].data.fd;
	243	ev = 0;
	244	if(evr[i].events & EPOLLIN)
	245	ev \|= EV_READ;
	246	if(evr[i].events & EPOLLOUT)
	247	ev \|= EV_WRITE;
	248	if(evr[i].events & ~(EPOLLIN \| EPOLLOUT))
	249	ev = -1;
	250	for(bl = fdlist[fd]; bl; bl = nbl) {
	251	nbl = bl->n2;
205ee933 FT	252	if((ev < 0) \|\| (ev & bl->ev)) {
	253	if(bl->id < 0) {
	254	resume(bl->th, ev);
	255	} else {
	256	bl->rev = ev;
	257	resume(bl->th, bl->id);
	258	}
	259	}
a6cda4dd FT	260	}
	261	}
	262	now = time(NULL);
	263	for(bl = blockers; bl; bl = nbl) {
	264	nbl = bl->n;
205ee933 FT	265	if((bl->to != 0) && (bl->to <= now)) {
	266	if(bl->id < 0) {
	267	resume(bl->th, 0);
	268	} else {
	269	bl->rev = 0;
	270	resume(bl->th, bl->id);
	271	}
	272	}
a6cda4dd FT	273	}
a6cda4dd FT	274	}
9d32586e FT	275	for(bl = blockers; bl; bl = bl->n)
9d32586e FT	276	remfd(bl);
a6cda4dd FT	277	close(epfd);
a6cda4dd FT	278	epfd = -1;
9d32586e FT	279	return(exitstatus);
	280	}
	281
	282	void exitioloop(int status)
	283	{
	284	exitstatus = status;
a6cda4dd	285	}