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/*
* handlreg.c
*
* implementation of xentoolcore_restrict_all
*
* Copyright (c) 2017 Citrix
* Part of a generic logging interface used by various dom0 userland libraries.
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation;
* version 2.1 of the License.
*
* This library 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
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with this library; If not, see <http://www.gnu.org/licenses/>.
*/
#include "xentoolcore_internal.h"
#include <sys/types.h>
#include <sys/stat.h>
#include <fcntl.h>
#include <unistd.h>
#include <pthread.h>
#include <assert.h>
static pthread_mutex_t handles_lock = PTHREAD_MUTEX_INITIALIZER;
static XEN_LIST_HEAD(, Xentoolcore__Active_Handle) handles;
static void lock(void) {
int e = pthread_mutex_lock(&handles_lock);
assert(!e);
}
static void unlock(void) {
int e = pthread_mutex_unlock(&handles_lock);
assert(!e);
}
void xentoolcore__register_active_handle(Xentoolcore__Active_Handle *ah) {
lock();
XEN_LIST_INSERT_HEAD(&handles, ah, entry);
unlock();
}
void xentoolcore__deregister_active_handle(Xentoolcore__Active_Handle *ah) {
lock();
XEN_LIST_REMOVE(ah, entry);
unlock();
}
int xentoolcore_restrict_all(domid_t domid) {
int r;
Xentoolcore__Active_Handle *ah;
lock();
XEN_LIST_FOREACH(ah, &handles, entry) {
r = ah->restrict_callback(ah, domid);
if (r) goto out;
}
r = 0;
out:
unlock();
return r;
}
int xentoolcore__restrict_by_dup2_null(int fd) {
int nullfd = -1, r;
if (fd < 0)
/* just in case */
return 0;
nullfd = open("/dev/null", O_RDONLY);
if (nullfd < 0) goto err;
r = dup2(nullfd, fd);
if (r < 0) goto err;
close(nullfd);
return 0;
err:
if (nullfd >= 0) close(nullfd);
return -1;
}
/*
* Local variables:
* mode: C
* c-file-style: "BSD"
* c-basic-offset: 4
* tab-width: 4
* indent-tabs-mode: nil
* End:
*/
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