main-loop: create main-loop.c
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
diff --git a/main-loop.c b/main-loop.c
new file mode 100644
index 0000000..bfecdb7
--- /dev/null
+++ b/main-loop.c
@@ -0,0 +1,495 @@
+/*
+ * QEMU System Emulator
+ *
+ * Copyright (c) 2003-2008 Fabrice Bellard
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
+ * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+ * THE SOFTWARE.
+ */
+#include "config-host.h"
+#include <unistd.h>
+#include <signal.h>
+#include <time.h>
+#include <errno.h>
+#include <sys/time.h>
+#include <stdbool.h>
+
+#ifdef _WIN32
+#include <windows.h>
+#include <winsock2.h>
+#include <ws2tcpip.h>
+#else
+#include <sys/socket.h>
+#include <netinet/in.h>
+#include <net/if.h>
+#include <arpa/inet.h>
+#include <sys/select.h>
+#include <sys/stat.h>
+#include "compatfd.h"
+#endif
+
+#include <glib.h>
+
+#include "main-loop.h"
+#include "qemu-timer.h"
+#include "slirp/libslirp.h"
+
+#ifndef _WIN32
+
+static int io_thread_fd = -1;
+
+void qemu_notify_event(void)
+{
+ /* Write 8 bytes to be compatible with eventfd. */
+ static const uint64_t val = 1;
+ ssize_t ret;
+
+ if (io_thread_fd == -1) {
+ return;
+ }
+ do {
+ ret = write(io_thread_fd, &val, sizeof(val));
+ } while (ret < 0 && errno == EINTR);
+
+ /* EAGAIN is fine, a read must be pending. */
+ if (ret < 0 && errno != EAGAIN) {
+ fprintf(stderr, "qemu_notify_event: write() failed: %s\n",
+ strerror(errno));
+ exit(1);
+ }
+}
+
+static void qemu_event_read(void *opaque)
+{
+ int fd = (intptr_t)opaque;
+ ssize_t len;
+ char buffer[512];
+
+ /* Drain the notify pipe. For eventfd, only 8 bytes will be read. */
+ do {
+ len = read(fd, buffer, sizeof(buffer));
+ } while ((len == -1 && errno == EINTR) || len == sizeof(buffer));
+}
+
+static int qemu_event_init(void)
+{
+ int err;
+ int fds[2];
+
+ err = qemu_eventfd(fds);
+ if (err == -1) {
+ return -errno;
+ }
+ err = fcntl_setfl(fds[0], O_NONBLOCK);
+ if (err < 0) {
+ goto fail;
+ }
+ err = fcntl_setfl(fds[1], O_NONBLOCK);
+ if (err < 0) {
+ goto fail;
+ }
+ qemu_set_fd_handler2(fds[0], NULL, qemu_event_read, NULL,
+ (void *)(intptr_t)fds[0]);
+
+ io_thread_fd = fds[1];
+ return 0;
+
+fail:
+ close(fds[0]);
+ close(fds[1]);
+ return err;
+}
+
+/* If we have signalfd, we mask out the signals we want to handle and then
+ * use signalfd to listen for them. We rely on whatever the current signal
+ * handler is to dispatch the signals when we receive them.
+ */
+static void sigfd_handler(void *opaque)
+{
+ int fd = (intptr_t)opaque;
+ struct qemu_signalfd_siginfo info;
+ struct sigaction action;
+ ssize_t len;
+
+ while (1) {
+ do {
+ len = read(fd, &info, sizeof(info));
+ } while (len == -1 && errno == EINTR);
+
+ if (len == -1 && errno == EAGAIN) {
+ break;
+ }
+
+ if (len != sizeof(info)) {
+ printf("read from sigfd returned %zd: %m\n", len);
+ return;
+ }
+
+ sigaction(info.ssi_signo, NULL, &action);
+ if ((action.sa_flags & SA_SIGINFO) && action.sa_sigaction) {
+ action.sa_sigaction(info.ssi_signo,
+ (siginfo_t *)&info, NULL);
+ } else if (action.sa_handler) {
+ action.sa_handler(info.ssi_signo);
+ }
+ }
+}
+
+static int qemu_signal_init(void)
+{
+ int sigfd;
+ sigset_t set;
+
+ /*
+ * SIG_IPI must be blocked in the main thread and must not be caught
+ * by sigwait() in the signal thread. Otherwise, the cpu thread will
+ * not catch it reliably.
+ */
+ sigemptyset(&set);
+ sigaddset(&set, SIG_IPI);
+ pthread_sigmask(SIG_BLOCK, &set, NULL);
+
+ sigemptyset(&set);
+ sigaddset(&set, SIGIO);
+ sigaddset(&set, SIGALRM);
+ sigaddset(&set, SIGBUS);
+ pthread_sigmask(SIG_BLOCK, &set, NULL);
+
+ sigfd = qemu_signalfd(&set);
+ if (sigfd == -1) {
+ fprintf(stderr, "failed to create signalfd\n");
+ return -errno;
+ }
+
+ fcntl_setfl(sigfd, O_NONBLOCK);
+
+ qemu_set_fd_handler2(sigfd, NULL, sigfd_handler, NULL,
+ (void *)(intptr_t)sigfd);
+
+ return 0;
+}
+
+#else /* _WIN32 */
+
+HANDLE qemu_event_handle;
+
+static void dummy_event_handler(void *opaque)
+{
+}
+
+static int qemu_event_init(void)
+{
+ qemu_event_handle = CreateEvent(NULL, FALSE, FALSE, NULL);
+ if (!qemu_event_handle) {
+ fprintf(stderr, "Failed CreateEvent: %ld\n", GetLastError());
+ return -1;
+ }
+ qemu_add_wait_object(qemu_event_handle, dummy_event_handler, NULL);
+ return 0;
+}
+
+void qemu_notify_event(void)
+{
+ if (!SetEvent(qemu_event_handle)) {
+ fprintf(stderr, "qemu_notify_event: SetEvent failed: %ld\n",
+ GetLastError());
+ exit(1);
+ }
+}
+
+static int qemu_signal_init(void)
+{
+ return 0;
+}
+#endif
+
+int qemu_init_main_loop(void)
+{
+ int ret;
+
+ qemu_mutex_lock_iothread();
+ ret = qemu_signal_init();
+ if (ret) {
+ return ret;
+ }
+
+ /* Note eventfd must be drained before signalfd handlers run */
+ ret = qemu_event_init();
+ if (ret) {
+ return ret;
+ }
+
+ return 0;
+}
+
+
+static GPollFD poll_fds[1024 * 2]; /* this is probably overkill */
+static int n_poll_fds;
+static int max_priority;
+
+static void glib_select_fill(int *max_fd, fd_set *rfds, fd_set *wfds,
+ fd_set *xfds, struct timeval *tv)
+{
+ GMainContext *context = g_main_context_default();
+ int i;
+ int timeout = 0, cur_timeout;
+
+ g_main_context_prepare(context, &max_priority);
+
+ n_poll_fds = g_main_context_query(context, max_priority, &timeout,
+ poll_fds, ARRAY_SIZE(poll_fds));
+ g_assert(n_poll_fds <= ARRAY_SIZE(poll_fds));
+
+ for (i = 0; i < n_poll_fds; i++) {
+ GPollFD *p = &poll_fds[i];
+
+ if ((p->events & G_IO_IN)) {
+ FD_SET(p->fd, rfds);
+ *max_fd = MAX(*max_fd, p->fd);
+ }
+ if ((p->events & G_IO_OUT)) {
+ FD_SET(p->fd, wfds);
+ *max_fd = MAX(*max_fd, p->fd);
+ }
+ if ((p->events & G_IO_ERR)) {
+ FD_SET(p->fd, xfds);
+ *max_fd = MAX(*max_fd, p->fd);
+ }
+ }
+
+ cur_timeout = (tv->tv_sec * 1000) + ((tv->tv_usec + 500) / 1000);
+ if (timeout >= 0 && timeout < cur_timeout) {
+ tv->tv_sec = timeout / 1000;
+ tv->tv_usec = (timeout % 1000) * 1000;
+ }
+}
+
+static void glib_select_poll(fd_set *rfds, fd_set *wfds, fd_set *xfds,
+ bool err)
+{
+ GMainContext *context = g_main_context_default();
+
+ if (!err) {
+ int i;
+
+ for (i = 0; i < n_poll_fds; i++) {
+ GPollFD *p = &poll_fds[i];
+
+ if ((p->events & G_IO_IN) && FD_ISSET(p->fd, rfds)) {
+ p->revents |= G_IO_IN;
+ }
+ if ((p->events & G_IO_OUT) && FD_ISSET(p->fd, wfds)) {
+ p->revents |= G_IO_OUT;
+ }
+ if ((p->events & G_IO_ERR) && FD_ISSET(p->fd, xfds)) {
+ p->revents |= G_IO_ERR;
+ }
+ }
+ }
+
+ if (g_main_context_check(context, max_priority, poll_fds, n_poll_fds)) {
+ g_main_context_dispatch(context);
+ }
+}
+
+#ifdef _WIN32
+/***********************************************************/
+/* Polling handling */
+
+typedef struct PollingEntry {
+ PollingFunc *func;
+ void *opaque;
+ struct PollingEntry *next;
+} PollingEntry;
+
+static PollingEntry *first_polling_entry;
+
+int qemu_add_polling_cb(PollingFunc *func, void *opaque)
+{
+ PollingEntry **ppe, *pe;
+ pe = g_malloc0(sizeof(PollingEntry));
+ pe->func = func;
+ pe->opaque = opaque;
+ for(ppe = &first_polling_entry; *ppe != NULL; ppe = &(*ppe)->next);
+ *ppe = pe;
+ return 0;
+}
+
+void qemu_del_polling_cb(PollingFunc *func, void *opaque)
+{
+ PollingEntry **ppe, *pe;
+ for(ppe = &first_polling_entry; *ppe != NULL; ppe = &(*ppe)->next) {
+ pe = *ppe;
+ if (pe->func == func && pe->opaque == opaque) {
+ *ppe = pe->next;
+ g_free(pe);
+ break;
+ }
+ }
+}
+
+/***********************************************************/
+/* Wait objects support */
+typedef struct WaitObjects {
+ int num;
+ HANDLE events[MAXIMUM_WAIT_OBJECTS + 1];
+ WaitObjectFunc *func[MAXIMUM_WAIT_OBJECTS + 1];
+ void *opaque[MAXIMUM_WAIT_OBJECTS + 1];
+} WaitObjects;
+
+static WaitObjects wait_objects = {0};
+
+int qemu_add_wait_object(HANDLE handle, WaitObjectFunc *func, void *opaque)
+{
+ WaitObjects *w = &wait_objects;
+ if (w->num >= MAXIMUM_WAIT_OBJECTS) {
+ return -1;
+ }
+ w->events[w->num] = handle;
+ w->func[w->num] = func;
+ w->opaque[w->num] = opaque;
+ w->num++;
+ return 0;
+}
+
+void qemu_del_wait_object(HANDLE handle, WaitObjectFunc *func, void *opaque)
+{
+ int i, found;
+ WaitObjects *w = &wait_objects;
+
+ found = 0;
+ for (i = 0; i < w->num; i++) {
+ if (w->events[i] == handle) {
+ found = 1;
+ }
+ if (found) {
+ w->events[i] = w->events[i + 1];
+ w->func[i] = w->func[i + 1];
+ w->opaque[i] = w->opaque[i + 1];
+ }
+ }
+ if (found) {
+ w->num--;
+ }
+}
+
+static void os_host_main_loop_wait(int *timeout)
+{
+ int ret, ret2, i;
+ PollingEntry *pe;
+
+ /* XXX: need to suppress polling by better using win32 events */
+ ret = 0;
+ for (pe = first_polling_entry; pe != NULL; pe = pe->next) {
+ ret |= pe->func(pe->opaque);
+ }
+ if (ret == 0) {
+ int err;
+ WaitObjects *w = &wait_objects;
+
+ qemu_mutex_unlock_iothread();
+ ret = WaitForMultipleObjects(w->num, w->events, FALSE, *timeout);
+ qemu_mutex_lock_iothread();
+ if (WAIT_OBJECT_0 + 0 <= ret && ret <= WAIT_OBJECT_0 + w->num - 1) {
+ if (w->func[ret - WAIT_OBJECT_0]) {
+ w->func[ret - WAIT_OBJECT_0](w->opaque[ret - WAIT_OBJECT_0]);
+ }
+
+ /* Check for additional signaled events */
+ for (i = (ret - WAIT_OBJECT_0 + 1); i < w->num; i++) {
+ /* Check if event is signaled */
+ ret2 = WaitForSingleObject(w->events[i], 0);
+ if (ret2 == WAIT_OBJECT_0) {
+ if (w->func[i]) {
+ w->func[i](w->opaque[i]);
+ }
+ } else if (ret2 != WAIT_TIMEOUT) {
+ err = GetLastError();
+ fprintf(stderr, "WaitForSingleObject error %d %d\n", i, err);
+ }
+ }
+ } else if (ret != WAIT_TIMEOUT) {
+ err = GetLastError();
+ fprintf(stderr, "WaitForMultipleObjects error %d %d\n", ret, err);
+ }
+ }
+
+ *timeout = 0;
+}
+#else
+static inline void os_host_main_loop_wait(int *timeout)
+{
+}
+#endif
+
+int main_loop_wait(int nonblocking)
+{
+ fd_set rfds, wfds, xfds;
+ int ret, nfds;
+ struct timeval tv;
+ int timeout;
+
+ if (nonblocking) {
+ timeout = 0;
+ } else {
+ timeout = qemu_calculate_timeout();
+ qemu_bh_update_timeout(&timeout);
+ }
+
+ os_host_main_loop_wait(&timeout);
+
+ tv.tv_sec = timeout / 1000;
+ tv.tv_usec = (timeout % 1000) * 1000;
+
+ /* poll any events */
+ /* XXX: separate device handlers from system ones */
+ nfds = -1;
+ FD_ZERO(&rfds);
+ FD_ZERO(&wfds);
+ FD_ZERO(&xfds);
+
+#ifdef CONFIG_SLIRP
+ slirp_select_fill(&nfds, &rfds, &wfds, &xfds);
+#endif
+ qemu_iohandler_fill(&nfds, &rfds, &wfds, &xfds);
+ glib_select_fill(&nfds, &rfds, &wfds, &xfds, &tv);
+
+ if (timeout > 0) {
+ qemu_mutex_unlock_iothread();
+ }
+
+ ret = select(nfds + 1, &rfds, &wfds, &xfds, &tv);
+
+ if (timeout > 0) {
+ qemu_mutex_lock_iothread();
+ }
+
+ glib_select_poll(&rfds, &wfds, &xfds, (ret < 0));
+ qemu_iohandler_poll(&rfds, &wfds, &xfds, ret);
+#ifdef CONFIG_SLIRP
+ slirp_select_poll(&rfds, &wfds, &xfds, (ret < 0));
+#endif
+
+ qemu_run_all_timers();
+
+ /* Check bottom-halves last in case any of the earlier events triggered
+ them. */
+ qemu_bh_poll();
+
+ return ret;
+}
