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/*
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* QEMU System Emulator
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*
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* Copyright (c) 2003-2008 Fabrice Bellard
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*
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* Permission is hereby granted, free of charge, to any person obtaining a copy
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* of this software and associated documentation files (the "Software"), to deal
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* in the Software without restriction, including without limitation the rights
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* to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
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* copies of the Software, and to permit persons to whom the Software is
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* furnished to do so, subject to the following conditions:
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*
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* The above copyright notice and this permission notice shall be included in
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* all copies or substantial portions of the Software.
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*
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* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
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* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
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* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
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* THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
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* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
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* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
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* THE SOFTWARE.
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*/
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#include "qemu-common.h" |
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#include "qemu-timer.h" |
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#include "slirp/slirp.h" |
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#include "main-loop.h" |
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#ifndef _WIN32
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#include "compatfd.h" |
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static int io_thread_fd = -1; |
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void qemu_notify_event(void) |
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{ |
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/* Write 8 bytes to be compatible with eventfd. */
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static const uint64_t val = 1; |
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ssize_t ret; |
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if (io_thread_fd == -1) { |
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return;
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} |
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do {
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ret = write(io_thread_fd, &val, sizeof(val));
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} while (ret < 0 && errno == EINTR); |
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/* EAGAIN is fine, a read must be pending. */
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if (ret < 0 && errno != EAGAIN) { |
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fprintf(stderr, "qemu_notify_event: write() failed: %s\n",
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strerror(errno)); |
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exit(1);
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} |
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} |
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static void qemu_event_read(void *opaque) |
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{ |
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int fd = (intptr_t)opaque;
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ssize_t len; |
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char buffer[512]; |
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/* Drain the notify pipe. For eventfd, only 8 bytes will be read. */
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do {
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len = read(fd, buffer, sizeof(buffer));
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} while ((len == -1 && errno == EINTR) || len == sizeof(buffer)); |
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} |
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static int qemu_event_init(void) |
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{ |
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int err;
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int fds[2]; |
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err = qemu_eventfd(fds); |
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if (err == -1) { |
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return -errno;
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} |
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err = fcntl_setfl(fds[0], O_NONBLOCK);
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if (err < 0) { |
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goto fail;
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} |
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err = fcntl_setfl(fds[1], O_NONBLOCK);
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if (err < 0) { |
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goto fail;
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} |
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qemu_set_fd_handler2(fds[0], NULL, qemu_event_read, NULL, |
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(void *)(intptr_t)fds[0]); |
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io_thread_fd = fds[1];
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return 0; |
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fail:
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close(fds[0]);
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close(fds[1]);
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return err;
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} |
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/* If we have signalfd, we mask out the signals we want to handle and then
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* use signalfd to listen for them. We rely on whatever the current signal
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* handler is to dispatch the signals when we receive them.
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*/
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static void sigfd_handler(void *opaque) |
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{ |
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int fd = (intptr_t)opaque;
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struct qemu_signalfd_siginfo info;
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struct sigaction action;
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ssize_t len; |
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while (1) { |
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do {
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len = read(fd, &info, sizeof(info));
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} while (len == -1 && errno == EINTR); |
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if (len == -1 && errno == EAGAIN) { |
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break;
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} |
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if (len != sizeof(info)) { |
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printf("read from sigfd returned %zd: %m\n", len);
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return;
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} |
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sigaction(info.ssi_signo, NULL, &action);
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if ((action.sa_flags & SA_SIGINFO) && action.sa_sigaction) {
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action.sa_sigaction(info.ssi_signo, |
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(siginfo_t *)&info, NULL);
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} else if (action.sa_handler) { |
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action.sa_handler(info.ssi_signo); |
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} |
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} |
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} |
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static int qemu_signal_init(void) |
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{ |
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int sigfd;
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sigset_t set; |
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/*
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* SIG_IPI must be blocked in the main thread and must not be caught
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* by sigwait() in the signal thread. Otherwise, the cpu thread will
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* not catch it reliably.
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*/
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sigemptyset(&set); |
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sigaddset(&set, SIG_IPI); |
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pthread_sigmask(SIG_BLOCK, &set, NULL);
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sigemptyset(&set); |
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sigaddset(&set, SIGIO); |
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sigaddset(&set, SIGALRM); |
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sigaddset(&set, SIGBUS); |
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pthread_sigmask(SIG_BLOCK, &set, NULL);
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sigfd = qemu_signalfd(&set); |
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if (sigfd == -1) { |
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fprintf(stderr, "failed to create signalfd\n");
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return -errno;
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} |
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fcntl_setfl(sigfd, O_NONBLOCK); |
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qemu_set_fd_handler2(sigfd, NULL, sigfd_handler, NULL, |
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(void *)(intptr_t)sigfd);
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return 0; |
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} |
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#else /* _WIN32 */ |
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HANDLE qemu_event_handle; |
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static void dummy_event_handler(void *opaque) |
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{ |
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} |
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static int qemu_event_init(void) |
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{ |
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qemu_event_handle = CreateEvent(NULL, FALSE, FALSE, NULL); |
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if (!qemu_event_handle) {
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fprintf(stderr, "Failed CreateEvent: %ld\n", GetLastError());
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return -1; |
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} |
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qemu_add_wait_object(qemu_event_handle, dummy_event_handler, NULL);
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return 0; |
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} |
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void qemu_notify_event(void) |
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{ |
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if (!SetEvent(qemu_event_handle)) {
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fprintf(stderr, "qemu_notify_event: SetEvent failed: %ld\n",
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GetLastError()); |
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exit(1);
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} |
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} |
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static int qemu_signal_init(void) |
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{ |
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return 0; |
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} |
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#endif
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int qemu_init_main_loop(void) |
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{ |
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int ret;
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qemu_mutex_lock_iothread(); |
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ret = qemu_signal_init(); |
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if (ret) {
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return ret;
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} |
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/* Note eventfd must be drained before signalfd handlers run */
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ret = qemu_event_init(); |
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if (ret) {
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return ret;
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} |
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return 0; |
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} |
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static GPollFD poll_fds[1024 * 2]; /* this is probably overkill */ |
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static int n_poll_fds; |
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static int max_priority; |
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static void glib_select_fill(int *max_fd, fd_set *rfds, fd_set *wfds, |
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fd_set *xfds, struct timeval *tv)
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{ |
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GMainContext *context = g_main_context_default(); |
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int i;
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int timeout = 0, cur_timeout; |
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g_main_context_prepare(context, &max_priority); |
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n_poll_fds = g_main_context_query(context, max_priority, &timeout, |
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poll_fds, ARRAY_SIZE(poll_fds)); |
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g_assert(n_poll_fds <= ARRAY_SIZE(poll_fds)); |
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for (i = 0; i < n_poll_fds; i++) { |
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GPollFD *p = &poll_fds[i]; |
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if ((p->events & G_IO_IN)) {
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FD_SET(p->fd, rfds); |
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*max_fd = MAX(*max_fd, p->fd); |
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} |
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if ((p->events & G_IO_OUT)) {
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FD_SET(p->fd, wfds); |
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*max_fd = MAX(*max_fd, p->fd); |
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} |
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if ((p->events & G_IO_ERR)) {
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FD_SET(p->fd, xfds); |
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*max_fd = MAX(*max_fd, p->fd); |
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} |
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} |
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cur_timeout = (tv->tv_sec * 1000) + ((tv->tv_usec + 500) / 1000); |
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if (timeout >= 0 && timeout < cur_timeout) { |
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tv->tv_sec = timeout / 1000;
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tv->tv_usec = (timeout % 1000) * 1000; |
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} |
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} |
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static void glib_select_poll(fd_set *rfds, fd_set *wfds, fd_set *xfds, |
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bool err)
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{ |
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GMainContext *context = g_main_context_default(); |
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if (!err) {
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int i;
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for (i = 0; i < n_poll_fds; i++) { |
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GPollFD *p = &poll_fds[i]; |
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if ((p->events & G_IO_IN) && FD_ISSET(p->fd, rfds)) {
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p->revents |= G_IO_IN; |
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} |
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if ((p->events & G_IO_OUT) && FD_ISSET(p->fd, wfds)) {
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p->revents |= G_IO_OUT; |
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} |
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if ((p->events & G_IO_ERR) && FD_ISSET(p->fd, xfds)) {
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p->revents |= G_IO_ERR; |
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} |
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} |
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} |
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if (g_main_context_check(context, max_priority, poll_fds, n_poll_fds)) {
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g_main_context_dispatch(context); |
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} |
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} |
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#ifdef _WIN32
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/***********************************************************/
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/* Polling handling */
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typedef struct PollingEntry { |
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PollingFunc *func; |
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void *opaque;
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struct PollingEntry *next;
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} PollingEntry; |
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static PollingEntry *first_polling_entry;
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int qemu_add_polling_cb(PollingFunc *func, void *opaque) |
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{ |
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PollingEntry **ppe, *pe; |
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pe = g_malloc0(sizeof(PollingEntry));
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pe->func = func; |
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pe->opaque = opaque; |
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for(ppe = &first_polling_entry; *ppe != NULL; ppe = &(*ppe)->next); |
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*ppe = pe; |
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return 0; |
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} |
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void qemu_del_polling_cb(PollingFunc *func, void *opaque) |
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{ |
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PollingEntry **ppe, *pe; |
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for(ppe = &first_polling_entry; *ppe != NULL; ppe = &(*ppe)->next) { |
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pe = *ppe; |
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if (pe->func == func && pe->opaque == opaque) {
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*ppe = pe->next; |
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g_free(pe); |
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break;
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} |
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} |
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} |
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/***********************************************************/
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/* Wait objects support */
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typedef struct WaitObjects { |
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int num;
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HANDLE events[MAXIMUM_WAIT_OBJECTS + 1];
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WaitObjectFunc *func[MAXIMUM_WAIT_OBJECTS + 1];
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void *opaque[MAXIMUM_WAIT_OBJECTS + 1]; |
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} WaitObjects; |
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static WaitObjects wait_objects = {0}; |
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int qemu_add_wait_object(HANDLE handle, WaitObjectFunc *func, void *opaque) |
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{ |
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WaitObjects *w = &wait_objects; |
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if (w->num >= MAXIMUM_WAIT_OBJECTS) {
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return -1; |
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} |
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w->events[w->num] = handle; |
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w->func[w->num] = func; |
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w->opaque[w->num] = opaque; |
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w->num++; |
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return 0; |
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} |
349 |
|
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void qemu_del_wait_object(HANDLE handle, WaitObjectFunc *func, void *opaque) |
351 |
{ |
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int i, found;
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WaitObjects *w = &wait_objects; |
354 |
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found = 0;
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for (i = 0; i < w->num; i++) { |
357 |
if (w->events[i] == handle) {
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found = 1;
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} |
360 |
if (found) {
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w->events[i] = w->events[i + 1];
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w->func[i] = w->func[i + 1];
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w->opaque[i] = w->opaque[i + 1];
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} |
365 |
} |
366 |
if (found) {
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w->num--; |
368 |
} |
369 |
} |
370 |
|
371 |
static void os_host_main_loop_wait(int *timeout) |
372 |
{ |
373 |
int ret, ret2, i;
|
374 |
PollingEntry *pe; |
375 |
|
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/* XXX: need to suppress polling by better using win32 events */
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ret = 0;
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for (pe = first_polling_entry; pe != NULL; pe = pe->next) { |
379 |
ret |= pe->func(pe->opaque); |
380 |
} |
381 |
if (ret == 0) { |
382 |
int err;
|
383 |
WaitObjects *w = &wait_objects; |
384 |
|
385 |
qemu_mutex_unlock_iothread(); |
386 |
ret = WaitForMultipleObjects(w->num, w->events, FALSE, *timeout); |
387 |
qemu_mutex_lock_iothread(); |
388 |
if (WAIT_OBJECT_0 + 0 <= ret && ret <= WAIT_OBJECT_0 + w->num - 1) { |
389 |
if (w->func[ret - WAIT_OBJECT_0]) {
|
390 |
w->func[ret - WAIT_OBJECT_0](w->opaque[ret - WAIT_OBJECT_0]); |
391 |
} |
392 |
|
393 |
/* Check for additional signaled events */
|
394 |
for (i = (ret - WAIT_OBJECT_0 + 1); i < w->num; i++) { |
395 |
/* Check if event is signaled */
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396 |
ret2 = WaitForSingleObject(w->events[i], 0);
|
397 |
if (ret2 == WAIT_OBJECT_0) {
|
398 |
if (w->func[i]) {
|
399 |
w->func[i](w->opaque[i]); |
400 |
} |
401 |
} else if (ret2 != WAIT_TIMEOUT) { |
402 |
err = GetLastError(); |
403 |
fprintf(stderr, "WaitForSingleObject error %d %d\n", i, err);
|
404 |
} |
405 |
} |
406 |
} else if (ret != WAIT_TIMEOUT) { |
407 |
err = GetLastError(); |
408 |
fprintf(stderr, "WaitForMultipleObjects error %d %d\n", ret, err);
|
409 |
} |
410 |
} |
411 |
|
412 |
*timeout = 0;
|
413 |
} |
414 |
#else
|
415 |
static inline void os_host_main_loop_wait(int *timeout) |
416 |
{ |
417 |
} |
418 |
#endif
|
419 |
|
420 |
int main_loop_wait(int nonblocking) |
421 |
{ |
422 |
fd_set rfds, wfds, xfds; |
423 |
int ret, nfds;
|
424 |
struct timeval tv;
|
425 |
int timeout;
|
426 |
|
427 |
if (nonblocking) {
|
428 |
timeout = 0;
|
429 |
} else {
|
430 |
timeout = qemu_calculate_timeout(); |
431 |
qemu_bh_update_timeout(&timeout); |
432 |
} |
433 |
|
434 |
os_host_main_loop_wait(&timeout); |
435 |
|
436 |
tv.tv_sec = timeout / 1000;
|
437 |
tv.tv_usec = (timeout % 1000) * 1000; |
438 |
|
439 |
/* poll any events */
|
440 |
/* XXX: separate device handlers from system ones */
|
441 |
nfds = -1;
|
442 |
FD_ZERO(&rfds); |
443 |
FD_ZERO(&wfds); |
444 |
FD_ZERO(&xfds); |
445 |
|
446 |
#ifdef CONFIG_SLIRP
|
447 |
slirp_select_fill(&nfds, &rfds, &wfds, &xfds); |
448 |
#endif
|
449 |
qemu_iohandler_fill(&nfds, &rfds, &wfds, &xfds); |
450 |
glib_select_fill(&nfds, &rfds, &wfds, &xfds, &tv); |
451 |
|
452 |
if (timeout > 0) { |
453 |
qemu_mutex_unlock_iothread(); |
454 |
} |
455 |
|
456 |
ret = select(nfds + 1, &rfds, &wfds, &xfds, &tv);
|
457 |
|
458 |
if (timeout > 0) { |
459 |
qemu_mutex_lock_iothread(); |
460 |
} |
461 |
|
462 |
glib_select_poll(&rfds, &wfds, &xfds, (ret < 0));
|
463 |
qemu_iohandler_poll(&rfds, &wfds, &xfds, ret); |
464 |
#ifdef CONFIG_SLIRP
|
465 |
slirp_select_poll(&rfds, &wfds, &xfds, (ret < 0));
|
466 |
#endif
|
467 |
|
468 |
qemu_run_all_timers(); |
469 |
|
470 |
/* Check bottom-halves last in case any of the earlier events triggered
|
471 |
them. */
|
472 |
qemu_bh_poll(); |
473 |
|
474 |
return ret;
|
475 |
} |