diff options
author | peter <peter@FreeBSD.org> | 2008-07-12 05:00:28 +0000 |
---|---|---|
committer | peter <peter@FreeBSD.org> | 2008-07-12 05:00:28 +0000 |
commit | ba8f85b49c38af7bc2a9acdef5dcde2de008d25e (patch) | |
tree | ceac31a567976fd5866cb5791b059781f6e045de /lib/bind/isc/ev_files.c | |
parent | 0f328cea2580ffb8f9e363be671a517787111472 (diff) | |
download | FreeBSD-src-ba8f85b49c38af7bc2a9acdef5dcde2de008d25e.zip FreeBSD-src-ba8f85b49c38af7bc2a9acdef5dcde2de008d25e.tar.gz |
Flatten bind9 vendor work area
Diffstat (limited to 'lib/bind/isc/ev_files.c')
-rw-r--r-- | lib/bind/isc/ev_files.c | 277 |
1 files changed, 277 insertions, 0 deletions
diff --git a/lib/bind/isc/ev_files.c b/lib/bind/isc/ev_files.c new file mode 100644 index 0000000..71de091 --- /dev/null +++ b/lib/bind/isc/ev_files.c @@ -0,0 +1,277 @@ +/* + * Copyright (c) 2004 by Internet Systems Consortium, Inc. ("ISC") + * Copyright (c) 1995-1999 by Internet Software Consortium + * + * Permission to use, copy, modify, and distribute this software for any + * purpose with or without fee is hereby granted, provided that the above + * copyright notice and this permission notice appear in all copies. + * + * THE SOFTWARE IS PROVIDED "AS IS" AND ISC DISCLAIMS ALL WARRANTIES + * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF + * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL ISC BE LIABLE FOR + * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES + * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN + * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT + * OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. + */ + +/* ev_files.c - implement asynch file IO for the eventlib + * vix 11sep95 [initial] + */ + +#if !defined(LINT) && !defined(CODECENTER) +static const char rcsid[] = "$Id: ev_files.c,v 1.5.18.3 2005/07/28 07:38:09 marka Exp $"; +#endif + +#include "port_before.h" +#include "fd_setsize.h" + +#include <sys/types.h> +#include <sys/time.h> +#include <sys/ioctl.h> + +#include <errno.h> +#include <fcntl.h> +#include <unistd.h> + +#include <isc/eventlib.h> +#include "eventlib_p.h" + +#include "port_after.h" + +static evFile *FindFD(const evContext_p *ctx, int fd, int eventmask); + +int +evSelectFD(evContext opaqueCtx, + int fd, + int eventmask, + evFileFunc func, + void *uap, + evFileID *opaqueID +) { + evContext_p *ctx = opaqueCtx.opaque; + evFile *id; + int mode; + + evPrintf(ctx, 1, + "evSelectFD(ctx %p, fd %d, mask 0x%x, func %p, uap %p)\n", + ctx, fd, eventmask, func, uap); + if (eventmask == 0 || (eventmask & ~EV_MASK_ALL) != 0) + EV_ERR(EINVAL); +#ifndef USE_POLL + if (fd > ctx->highestFD) + EV_ERR(EINVAL); +#endif + OK(mode = fcntl(fd, F_GETFL, NULL)); /*%< side effect: validate fd. */ + /* + * The first time we touch a file descriptor, we need to check to see + * if the application already had it in O_NONBLOCK mode and if so, all + * of our deselect()'s have to leave it in O_NONBLOCK. If not, then + * all but our last deselect() has to leave it in O_NONBLOCK. + */ +#ifdef USE_POLL + /* Make sure both ctx->pollfds[] and ctx->fdTable[] are large enough */ + if (fd >= ctx->maxnfds && evPollfdRealloc(ctx, 1, fd) != 0) + EV_ERR(ENOMEM); +#endif /* USE_POLL */ + id = FindFD(ctx, fd, EV_MASK_ALL); + if (id == NULL) { + if (mode & PORT_NONBLOCK) + FD_SET(fd, &ctx->nonblockBefore); + else { +#ifdef USE_FIONBIO_IOCTL + int on = 1; + OK(ioctl(fd, FIONBIO, (char *)&on)); +#else + OK(fcntl(fd, F_SETFL, mode | PORT_NONBLOCK)); +#endif + FD_CLR(fd, &ctx->nonblockBefore); + } + } + + /* + * If this descriptor is already in use, search for it again to see + * if any of the eventmask bits we want to set are already captured. + * We cannot usefully capture the same fd event more than once in the + * same context. + */ + if (id != NULL && FindFD(ctx, fd, eventmask) != NULL) + EV_ERR(ETOOMANYREFS); + + /* Allocate and fill. */ + OKNEW(id); + id->func = func; + id->uap = uap; + id->fd = fd; + id->eventmask = eventmask; + + /* + * Insert at head. Order could be important for performance if we + * believe that evGetNext()'s accesses to the fd_sets will be more + * serial and therefore more cache-lucky if the list is ordered by + * ``fd.'' We do not believe these things, so we don't do it. + * + * The interesting sequence is where GetNext() has cached a select() + * result and the caller decides to evSelectFD() on some descriptor. + * Since GetNext() starts at the head, it can miss new entries we add + * at the head. This is not a serious problem since the event being + * evSelectFD()'d for has to occur before evSelectFD() is called for + * the file event to be considered "missed" -- a real corner case. + * Maintaining a "tail" pointer for ctx->files would fix this, but I'm + * not sure it would be ``more correct.'' + */ + if (ctx->files != NULL) + ctx->files->prev = id; + id->prev = NULL; + id->next = ctx->files; + ctx->files = id; + + /* Insert into fd table. */ + if (ctx->fdTable[fd] != NULL) + ctx->fdTable[fd]->fdprev = id; + id->fdprev = NULL; + id->fdnext = ctx->fdTable[fd]; + ctx->fdTable[fd] = id; + + /* Turn on the appropriate bits in the {rd,wr,ex}Next fd_set's. */ + if (eventmask & EV_READ) + FD_SET(fd, &ctx->rdNext); + if (eventmask & EV_WRITE) + FD_SET(fd, &ctx->wrNext); + if (eventmask & EV_EXCEPT) + FD_SET(fd, &ctx->exNext); + + /* Update fdMax. */ + if (fd > ctx->fdMax) + ctx->fdMax = fd; + + /* Remember the ID if the caller provided us a place for it. */ + if (opaqueID) + opaqueID->opaque = id; + + return (0); +} + +int +evDeselectFD(evContext opaqueCtx, evFileID opaqueID) { + evContext_p *ctx = opaqueCtx.opaque; + evFile *del = opaqueID.opaque; + evFile *cur; + int mode, eventmask; + + if (!del) { + evPrintf(ctx, 11, "evDeselectFD(NULL) ignored\n"); + errno = EINVAL; + return (-1); + } + + evPrintf(ctx, 1, "evDeselectFD(fd %d, mask 0x%x)\n", + del->fd, del->eventmask); + + /* Get the mode. Unless the file has been closed, errors are bad. */ + mode = fcntl(del->fd, F_GETFL, NULL); + if (mode == -1 && errno != EBADF) + EV_ERR(errno); + + /* Remove from the list of files. */ + if (del->prev != NULL) + del->prev->next = del->next; + else + ctx->files = del->next; + if (del->next != NULL) + del->next->prev = del->prev; + + /* Remove from the fd table. */ + if (del->fdprev != NULL) + del->fdprev->fdnext = del->fdnext; + else + ctx->fdTable[del->fd] = del->fdnext; + if (del->fdnext != NULL) + del->fdnext->fdprev = del->fdprev; + + /* + * If the file descriptor does not appear in any other select() entry, + * and if !EV_WASNONBLOCK, and if we got no EBADF when we got the mode + * earlier, then: restore the fd to blocking status. + */ + if (!(cur = FindFD(ctx, del->fd, EV_MASK_ALL)) && + !FD_ISSET(del->fd, &ctx->nonblockBefore) && + mode != -1) { + /* + * Note that we won't return an error status to the caller if + * this fcntl() fails since (a) we've already done the work + * and (b) the caller didn't ask us anything about O_NONBLOCK. + */ +#ifdef USE_FIONBIO_IOCTL + int off = 0; + (void) ioctl(del->fd, FIONBIO, (char *)&off); +#else + (void) fcntl(del->fd, F_SETFL, mode & ~PORT_NONBLOCK); +#endif + } + + /* + * Now find all other uses of this descriptor and OR together an event + * mask so that we don't turn off {rd,wr,ex}Next bits that some other + * file event is using. As an optimization, stop if the event mask + * fills. + */ + eventmask = 0; + for ((void)NULL; + cur != NULL && eventmask != EV_MASK_ALL; + cur = cur->next) + if (cur->fd == del->fd) + eventmask |= cur->eventmask; + + /* OK, now we know which bits we can clear out. */ + if (!(eventmask & EV_READ)) { + FD_CLR(del->fd, &ctx->rdNext); + if (FD_ISSET(del->fd, &ctx->rdLast)) { + FD_CLR(del->fd, &ctx->rdLast); + ctx->fdCount--; + } + } + if (!(eventmask & EV_WRITE)) { + FD_CLR(del->fd, &ctx->wrNext); + if (FD_ISSET(del->fd, &ctx->wrLast)) { + FD_CLR(del->fd, &ctx->wrLast); + ctx->fdCount--; + } + } + if (!(eventmask & EV_EXCEPT)) { + FD_CLR(del->fd, &ctx->exNext); + if (FD_ISSET(del->fd, &ctx->exLast)) { + FD_CLR(del->fd, &ctx->exLast); + ctx->fdCount--; + } + } + + /* If this was the maxFD, find the new one. */ + if (del->fd == ctx->fdMax) { + ctx->fdMax = -1; + for (cur = ctx->files; cur; cur = cur->next) + if (cur->fd > ctx->fdMax) + ctx->fdMax = cur->fd; + } + + /* If this was the fdNext, cycle that to the next entry. */ + if (del == ctx->fdNext) + ctx->fdNext = del->next; + + /* Couldn't free it before now since we were using fields out of it. */ + FREE(del); + + return (0); +} + +static evFile * +FindFD(const evContext_p *ctx, int fd, int eventmask) { + evFile *id; + + for (id = ctx->fdTable[fd]; id != NULL; id = id->fdnext) + if (id->fd == fd && (id->eventmask & eventmask) != 0) + break; + return (id); +} + +/*! \file */ |