X-Git-Url: http://www.dolda2000.com/gitweb/?a=blobdiff_plain;f=lib%2Fmtio.c;h=d7f36ac82d31be22e5d5c9111476d16ee2a15e99;hb=b71ad67f41a9e99bd243d57b5038de28f1696f27;hp=e4166f5aab877b03fc32abbeac8b1bb1e8ffa3f8;hpb=470938bdc9149ae9c7befd0cd983f46fcc056192;p=ashd.git

diff --git a/lib/mtio.c b/lib/mtio.c
index e4166f5..d7f36ac 100644
--- a/lib/mtio.c
+++ b/lib/mtio.c
@@ -16,327 +16,23 @@
     along with this program.  If not, see <http://www.gnu.org/licenses/>.
 */
 
+#ifdef HAVE_CONFIG_H
+#include <config.h>
+#endif
 #include <stdlib.h>
 #include <stdio.h>
-#include <fcntl.h>
 #include <unistd.h>
+#include <fcntl.h>
 #include <string.h>
-#include <time.h>
 #include <errno.h>
-#include <sys/select.h>
 #include <sys/socket.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;
-
-#ifdef HAVE_EPOLL
-
-/* 
- * Support for epoll. Optimally, different I/O loops should be split
- * into different files for greater clarity, but I'll save that fun
- * for another day. 
- *
- * Scroll down to #else for the normal select loop.
- */
-
-#include <sys/epoll.h>
-
-struct blocker {
-    struct blocker *n, *p, *n2, *p2;
-    int fd, reg;
-    int ev;
-    time_t to;
-    struct muth *th;
-};
-
-static int epfd = -1, fdln = 0;
-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));
-	}
-    }
-}
-
-int block(int fd, int ev, time_t to)
-{
-    struct blocker *bl;
-    int rv;
-    
-    omalloc(bl);
-    bl->fd = fd;
-    bl->ev = ev;
-    if(to > 0)
-	bl->to = time(NULL) + to;
-    bl->th = current;
-    if((epfd >= 0) && regfd(bl)) {
-	free(bl);
-	return(-1);
-    }
-    bl->n = blockers;
-    if(blockers)
-	blockers->p = bl;
-    blockers = bl;
-    rv = yield();
-    if(bl->n)
-	bl->n->p = bl->p;
-    if(bl->p)
-	bl->p->n = bl->n;
-    if(bl == blockers)
-	blockers = bl->n;
-    remfd(bl);
-    free(bl);
-    return(rv);
-}
-
-void ioloop(void)
-{
-    struct blocker *bl, *nbl;
-    struct epoll_event evr[16];
-    int i, fd, nev, ev, toval;
-    time_t now, timeout;
-    
-    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;
-	nev = epoll_wait(epfd, evr, sizeof(evr) / sizeof(*evr), toval);
-	if(nev < 0) {
-	    if(errno != EINTR) {
-		flog(LOG_CRIT, "ioloop: select 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))
-		    resume(bl->th, ev);
-	    }
-	}
-	now = time(NULL);
-	for(bl = blockers; bl; bl = nbl) {
-	    nbl = bl->n;
-	    if((bl->to != 0) && (bl->to <= now))
-		resume(bl->th, 0);
-	}
-    }
-    close(epfd);
-    epfd = -1;
-}
-
-#else
-
-struct blocker {
-    struct blocker *n, *p;
-    int fd;
-    int ev;
-    time_t to;
-    struct muth *th;
-};
-
-int block(int fd, int ev, time_t to)
-{
-    struct blocker *bl;
-    int rv;
-    
-    omalloc(bl);
-    bl->fd = fd;
-    bl->ev = ev;
-    if(to > 0)
-	bl->to = time(NULL) + to;
-    bl->th = current;
-    bl->n = blockers;
-    if(blockers)
-	blockers->p = bl;
-    blockers = bl;
-    rv = yield();
-    if(bl->n)
-	bl->n->p = bl->p;
-    if(bl->p)
-	bl->p->n = bl->n;
-    if(bl == blockers)
-	blockers = bl->n;
-    free(bl);
-    return(rv);
-}
-
-void ioloop(void)
-{
-    int ret;
-    fd_set rfds, wfds, efds;
-    struct blocker *bl, *nbl;
-    struct timeval toval;
-    time_t now, timeout;
-    int maxfd;
-    int ev;
-    
-    while(blockers != NULL) {
-	FD_ZERO(&rfds);
-	FD_ZERO(&wfds);
-	FD_ZERO(&efds);
-	maxfd = 0;
-	now = time(NULL);
-	timeout = 0;
-	for(bl = blockers; bl; bl = bl->n) {
-	    if(bl->ev & EV_READ)
-		FD_SET(bl->fd, &rfds);
-	    if(bl->ev & EV_WRITE)
-		FD_SET(bl->fd, &wfds);
-	    FD_SET(bl->fd, &efds);
-	    if(bl->fd > maxfd)
-		maxfd = bl->fd;
-	    if((bl->to != 0) && ((timeout == 0) || (timeout > bl->to)))
-		timeout = bl->to;
-	}
-	toval.tv_sec = timeout - now;
-	toval.tv_usec = 0;
-	ret = select(maxfd + 1, &rfds, &wfds, &efds, timeout?(&toval):NULL);
-	if(ret < 0) {
-	    if(errno != EINTR) {
-		flog(LOG_CRIT, "ioloop: select errored out: %s", strerror(errno));
-		/* To avoid CPU hogging in case it's bad, which it
-		 * probably is. */
-		sleep(1);
-	    }
-	}
-	now = time(NULL);
-	for(bl = blockers; bl; bl = nbl) {
-	    nbl = bl->n;
-	    ev = 0;
-	    if(FD_ISSET(bl->fd, &rfds))
-		ev |= EV_READ;
-	    if(FD_ISSET(bl->fd, &wfds))
-		ev |= EV_WRITE;
-	    if(FD_ISSET(bl->fd, &efds))
-		ev = -1;
-	    if((ev < 0) || (ev & bl->ev))
-		resume(bl->th, ev);
-	    else if((bl->to != 0) && (bl->to <= now))
-		resume(bl->th, 0);
-	}
-    }
-}
-
-#endif
-
-struct stdiofd {
-    int fd;
-    int sock;
-    int timeout;
-};
-
-static ssize_t mtread(void *cookie, char *buf, size_t len)
+static ssize_t mtread(void *cookie, void *buf, size_t len)
 {
     struct stdiofd *d = cookie;
     int ev;
@@ -361,39 +57,30 @@ static ssize_t mtread(void *cookie, char *buf, size_t len)
     }
 }
 
-static ssize_t mtwrite(void *cookie, const char *buf, size_t len)
+static ssize_t mtwrite(void *cookie, const void *buf, size_t len)
 {
     struct stdiofd *d = cookie;
     int ev;
-    size_t off;
     ssize_t ret;
     
-    off = 0;
-    while(off < len) {
+    while(1) {
 	if(d->sock)
-	    ret = send(d->fd, buf + off, len - off, MSG_DONTWAIT | MSG_NOSIGNAL);
+	    ret = send(d->fd, buf, len, MSG_DONTWAIT | MSG_NOSIGNAL);
 	else
-	    ret = write(d->fd, buf + off, len - off);
-	if(ret < 0) {
-	    if(errno == EAGAIN) {
-		ev = block(d->fd, EV_WRITE, d->timeout);
-		if(ev < 0) {
-		    /* If we just go on, we should get the real error. */
-		    continue;
-		} else if(ev == 0) {
-		    errno = ETIMEDOUT;
-		    return(off);
-		} else {
-		    continue;
-		}
-	    } else {
-		return(off);
+	    ret = write(d->fd, buf, len);
+	if((ret < 0) && (errno == EAGAIN)) {
+	    ev = block(d->fd, EV_WRITE, d->timeout);
+	    if(ev < 0) {
+		/* If we just go on, we should get the real error. */
+		continue;
+	    } else if(ev == 0) {
+		errno = ETIMEDOUT;
+		return(-1);
 	    }
 	} else {
-	    off += ret;
+	    return(ret);
 	}
     }
-    return(off);
 }
 
 static int mtclose(void *cookie)
@@ -405,25 +92,137 @@ static int mtclose(void *cookie)
     return(0);
 }
 
-static cookie_io_functions_t iofuns = {
-    .read = mtread,
-    .write = mtwrite,
-    .close = mtclose,
-};
-
-FILE *mtstdopen(int fd, int issock, int timeout, char *mode)
+FILE *mtstdopen(int fd, int issock, int timeout, char *mode, struct stdiofd **infop)
 {
     struct stdiofd *d;
     FILE *ret;
+    int r, w;
     
+    if(!strcmp(mode, "r")) {
+	r = 1; w = 0;
+    } else if(!strcmp(mode, "w")) {
+	r = 0; w = 1;
+    } else if(!strcmp(mode, "r+")) {
+	r = w = 1;
+    } else {
+	return(NULL);
+    }
     omalloc(d);
     d->fd = fd;
     d->sock = issock;
     d->timeout = timeout;
-    ret = fopencookie(d, mode, iofuns);
-    if(!ret)
+    if(!(ret = funstdio(d, r?mtread:NULL, w?mtwrite:NULL, NULL, mtclose))) {
 	free(d);
-    else
-	fcntl(fd, F_SETFL, fcntl(fd, F_GETFL) | O_NONBLOCK);
+	return(NULL);
+    }
+    fcntl(fd, F_SETFL, fcntl(fd, F_GETFL) | O_NONBLOCK);
+    if(infop)
+	*infop = d;
+    return(ret);
+}
+
+struct pipe {
+    struct charbuf data;
+    size_t bufmax;
+    int closed;
+    struct muth *r, *w;
+};
+
+static void freepipe(struct pipe *p)
+{
+    buffree(p->data);
+    free(p);
+}
+
+static ssize_t piperead(void *pdata, void *buf, size_t len)
+{
+    struct pipe *p = pdata;
+    ssize_t ret;
+    
+    while(p->data.d == 0) {
+	if(p->closed & 2)
+	    return(0);
+	if(p->r) {
+	    errno = EBUSY;
+	    return(-1);
+	}
+	p->r = current;
+	yield();
+	p->r = NULL;
+    }
+    ret = min(len, p->data.d);
+    memcpy(buf, p->data.b, ret);
+    memmove(p->data.b, p->data.b + ret, p->data.d -= ret);
+    if(p->w)
+	resume(p->w, 0);
     return(ret);
 }
+
+static int piperclose(void *pdata)
+{
+    struct pipe *p = pdata;
+    
+    if(p->closed & 2) {
+	freepipe(p);
+    } else {
+	p->closed |= 1;
+	if(p->w)
+	    resume(p->w, 0);
+    }
+    return(0);
+}
+
+static ssize_t pipewrite(void *pdata, const void *buf, size_t len)
+{
+    struct pipe *p = pdata;
+    ssize_t ret;
+    
+    if(p->closed & 1) {
+	errno = EPIPE;
+	return(-1);
+    }
+    while(p->data.d >= p->bufmax) {
+	if(p->w) {
+	    errno = EBUSY;
+	    return(-1);
+	}
+	p->w = current;
+	yield();
+	p->w = NULL;
+	if(p->closed & 1) {
+	    errno = EPIPE;
+	    return(-1);
+	}
+    }
+    ret = min(len, p->bufmax - p->data.d);
+    sizebuf(p->data, p->data.d + ret);
+    memcpy(p->data.b + p->data.d, buf, ret);
+    p->data.d += ret;
+    if(p->r)
+	resume(p->r, 0);
+    return(ret);
+}
+
+static int pipewclose(void *pdata)
+{
+    struct pipe *p = pdata;
+    
+    if(p->closed & 1) {
+	freepipe(p);
+    } else {
+	p->closed |= 2;
+	if(p->r)
+	    resume(p->r, 0);
+    }
+    return(0);
+}
+
+void mtiopipe(FILE **read, FILE **write)
+{
+    struct pipe *p;
+    
+    omalloc(p);
+    p->bufmax = 4096;
+    *read = funstdio(p, piperead, NULL, NULL, piperclose);
+    *write = funstdio(p, NULL, pipewrite, NULL, pipewclose);
+}