Module Name: src
Committed By: pooka
Date: Sat Jan 8 21:30:24 UTC 2011
Modified Files:
src/lib/librumphijack: hijack.c
Log Message:
Support dual kernel select() by emulating it with pollts(). It
would have been much easier if up to and including 5.0 we wouldn't
silently cap the nfds argument to poll(!!!).
Makes things like socket(1) work out-of-the-box, and pretty much
every other decidedly prehistoric select() user.
(netcat is a slight exception since it sets FD_SETSIZE, a.k.a.
interface-of-the-year, to 16)
To generate a diff of this commit:
cvs rdiff -u -r1.3 -r1.4 src/lib/librumphijack/hijack.c
Please note that diffs are not public domain; they are subject to the
copyright notices on the relevant files.
Modified files:
Index: src/lib/librumphijack/hijack.c
diff -u src/lib/librumphijack/hijack.c:1.3 src/lib/librumphijack/hijack.c:1.4
--- src/lib/librumphijack/hijack.c:1.3 Sat Jan 8 18:11:46 2011
+++ src/lib/librumphijack/hijack.c Sat Jan 8 21:30:24 2011
@@ -1,4 +1,4 @@
-/* $NetBSD: hijack.c,v 1.3 2011/01/08 18:11:46 pooka Exp $ */
+/* $NetBSD: hijack.c,v 1.4 2011/01/08 21:30:24 pooka Exp $ */
/*-
* Copyright (c) 2011 Antti Kantee. All Rights Reserved.
@@ -26,7 +26,7 @@
*/
#include <sys/cdefs.h>
-__RCSID("$NetBSD: hijack.c,v 1.3 2011/01/08 18:11:46 pooka Exp $");
+__RCSID("$NetBSD: hijack.c,v 1.4 2011/01/08 21:30:24 pooka Exp $");
#include <sys/param.h>
#include <sys/types.h>
@@ -62,7 +62,7 @@
RUMPCALL_WRITE, RUMPCALL_WRITEV,
RUMPCALL_IOCTL, RUMPCALL_FCNTL,
RUMPCALL_CLOSE,
- RUMPCALL_SELECT, RUMPCALL_POLLTS,
+ RUMPCALL_POLLTS,
RUMPCALL__NUM
};
@@ -88,7 +88,6 @@
"ioctl",
"fcntl",
"close",
- "__select50",
"__pollts50",
};
@@ -99,8 +98,6 @@
static int (*host_ioctl)(int, unsigned long, ...);
static int (*host_fcntl)(int, int, ...);
static int (*host_close)(int);
-static int (*host_select)(int, fd_set *, fd_set *, fd_set *,
- struct timeval *);
static int (*host_pollts)(struct pollfd *, nfds_t,
const struct timespec *, const sigset_t *);
static pid_t (*host_fork)(void);
@@ -143,7 +140,6 @@
host_ioctl = dlsym(RTLD_NEXT, "ioctl");
host_fcntl = dlsym(RTLD_NEXT, "fcntl");
host_close = dlsym(RTLD_NEXT, "close");
- host_select = dlsym(RTLD_NEXT, "select");
host_pollts = dlsym(RTLD_NEXT, "pollts");
host_fork = dlsym(RTLD_NEXT, "fork");
host_dup2 = dlsym(RTLD_NEXT, "dup2");
@@ -586,79 +582,106 @@
return op_close(fd);
}
-/*
- * select() has more than one implication. e.g. we cannot know
- * the caller's FD_SETSIZE. So just assume something and hope.
- */
-static void
-checkset(fd_set *setti, int nfds, int *hostcall, int *rumpcall)
+int
+select(int nfds, fd_set *readfds, fd_set *writefds, fd_set *exceptfds,
+ struct timeval *timeout)
{
- int i;
-
- if (!setti)
- return;
-
- for (i = 0; i < MIN(nfds, FD_SETSIZE); i++) {
- if (FD_ISSET(i, setti)) {
- if (fd_isrump(i))
- *rumpcall = 1;
- else
- *hostcall = 1;
+ struct pollfd *pfds;
+ struct timespec ts, *tsp = NULL;
+ nfds_t i, j, realnfds;
+ int rv, incr;
+
+ /*
+ * Well, first we must scan the fds to figure out how many
+ * fds there really are. This is because up to and including
+ * nb5 poll() silently refuses nfds > process_open_fds.
+ * Seems to be fixed in current, thank the maker.
+ * god damn cluster...bomb.
+ */
+
+ for (i = 0, realnfds = 0; i < nfds; i++) {
+ if (readfds && FD_ISSET(i, readfds)) {
+ realnfds++;
+ continue;
+ }
+ if (writefds && FD_ISSET(i, writefds)) {
+ realnfds++;
+ continue;
+ }
+ if (exceptfds && FD_ISSET(i, exceptfds)) {
+ realnfds++;
+ continue;
}
}
-}
-
-static void
-adjustset(fd_set *setti, int nfds, int (*fdadj)(int))
-{
- int fd, i;
- if (!setti)
- return;
+ pfds = malloc(sizeof(*pfds) * realnfds);
+ if (!pfds)
+ return -1;
- for (i = 0; i < MIN(nfds, FD_SETSIZE); i++) {
- if (FD_ISSET(i, setti)) {
- FD_CLR(i, setti);
- fd = fdadj(fd);
- FD_SET(fd, setti);
+ for (i = 0, j = 0; i < nfds; i++) {
+ incr = 0;
+ pfds[j].events = pfds[j].revents = 0;
+ if (readfds && FD_ISSET(i, readfds)) {
+ pfds[j].fd = i;
+ pfds[j].events |= POLLIN;
+ incr=1;
+ }
+ if (writefds && FD_ISSET(i, writefds)) {
+ pfds[j].fd = i;
+ pfds[j].events |= POLLOUT;
+ incr=1;
+ }
+ if (exceptfds && FD_ISSET(i, exceptfds)) {
+ pfds[j].fd = i;
+ pfds[j].events |= POLLHUP|POLLERR;
+ incr=1;
}
+ if (incr)
+ j++;
}
-}
-int
-select(int nfds, fd_set *readfds, fd_set *writefds, fd_set *exceptfds,
- struct timeval *timeout)
-{
- int (*op_select)(int, fd_set *, fd_set *, fd_set *, struct timeval *);
- int hostcall = 0, rumpcall = 0;
- int rv;
-
- checkset(readfds, nfds, &hostcall, &rumpcall);
- checkset(writefds, nfds, &hostcall, &rumpcall);
- checkset(exceptfds, nfds, &hostcall, &rumpcall);
-
- if (hostcall && rumpcall) {
- fprintf(stderr, "cannot select() two kernels! (fixme)\n");
- return EINVAL;
+ if (timeout) {
+ TIMEVAL_TO_TIMESPEC(timeout, &ts);
+ tsp = &ts;
}
-
- if (hostcall) {
- op_select = host_select;
- } else {
- adjustset(readfds, nfds, fd_host2rump);
- adjustset(writefds, nfds, fd_host2rump);
- adjustset(exceptfds, nfds, fd_host2rump);
- op_select = rumpcalls[RUMPCALL_SELECT];
+ rv = pollts(pfds, realnfds, tsp, NULL);
+ if (rv <= 0)
+ goto out;
+
+ /*
+ * ok, harvest results. first zero out entries (can't use
+ * FD_ZERO for the obvious select-me-not reason). whee.
+ */
+ for (i = 0; i < nfds; i++) {
+ if (readfds)
+ FD_CLR(i, readfds);
+ if (writefds)
+ FD_CLR(i, writefds);
+ if (exceptfds)
+ FD_CLR(i, exceptfds);
}
- DPRINTF(("select\n"));
- rv = op_select(nfds+HIJACK_SELECT,
- readfds, writefds, exceptfds, timeout);
- if (rumpcall) {
- adjustset(readfds, nfds, fd_rump2host);
- adjustset(writefds, nfds, fd_rump2host);
- adjustset(exceptfds, nfds, fd_rump2host);
+ /* and then plug in the results */
+ for (i = 0; i < realnfds; i++) {
+ if (readfds) {
+ if (pfds[i].revents & POLLIN) {
+ FD_SET(pfds[i].fd, readfds);
+ }
+ }
+ if (writefds) {
+ if (pfds[i].revents & POLLOUT) {
+ FD_SET(pfds[i].fd, writefds);
+ }
+ }
+ if (exceptfds) {
+ if (pfds[i].revents & (POLLHUP|POLLERR)) {
+ FD_SET(pfds[i].fd, exceptfds);
+ }
+ }
}
+
+ out:
+ free(pfds);
return rv;
}
