link the main loop and its dependencies into the tools

Using the main loop code from QEMU enables tools to operate fully
asynchronously.  Advantages include better Windows portability (for some
definition of portability) over glib's.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

Makefile

@@ -147,8 +147,9 @@ endif
 qemu-img.o: qemu-img-cmds.h
 qemu-img.o qemu-tool.o qemu-nbd.o qemu-io.o cmd.o qemu-ga.o: $(GENERATED_HEADERS)
 
-tools-obj-y = qemu-tool.o $(oslib-obj-y) $(trace-obj-y) \
-	qemu-timer-common.o cutils.o
+tools-obj-y = $(oslib-obj-y) $(trace-obj-y) qemu-tool.o qemu-timer.o \
+	qemu-timer-common.o main-loop.o notify.o iohandler.o cutils.o async.o
+tools-obj-$(CONFIG_POSIX) += compatfd.o
 
 qemu-img$(EXESUF): qemu-img.o $(tools-obj-y) $(block-obj-y)
 qemu-nbd$(EXESUF): qemu-nbd.o $(tools-obj-y) $(block-obj-y)

main-loop.h

@@ -324,6 +324,9 @@ int qemu_add_child_watch(pid_t pid);
  * by threads other than the main loop thread when calling
  * qemu_bh_new(), qemu_set_fd_handler() and basically all other
  * functions documented in this file.
+ *
+ * NOTE: tools currently are single-threaded and qemu_mutex_lock_iothread
+ * is a no-op there.
  */
 void qemu_mutex_lock_iothread(void);
 
@@ -336,6 +339,9 @@ void qemu_mutex_lock_iothread(void);
  * as soon as possible by threads other than the main loop thread,
  * because it prevents the main loop from processing callbacks,
  * including timers and bottom halves.
+ *
+ * NOTE: tools currently are single-threaded and qemu_mutex_unlock_iothread
+ * is a no-op there.
  */
 void qemu_mutex_unlock_iothread(void);
 

os-posix.c

@@ -42,11 +42,6 @@
 
 #ifdef CONFIG_LINUX
 #include <sys/prctl.h>
-#include <sys/syscall.h>
-#endif
-
-#ifdef CONFIG_EVENTFD
-#include <sys/eventfd.h>
 #endif
 
 static struct passwd *user_pwd;
@@ -333,34 +328,6 @@ void os_set_line_buffering(void)
     setvbuf(stdout, NULL, _IOLBF, 0);
 }
 
-/*
- * Creates an eventfd that looks like a pipe and has EFD_CLOEXEC set.
- */
-int qemu_eventfd(int fds[2])
-{
-#ifdef CONFIG_EVENTFD
-    int ret;
-
-    ret = eventfd(0, 0);
-    if (ret >= 0) {
-        fds[0] = ret;
-        qemu_set_cloexec(ret);
-        if ((fds[1] = dup(ret)) == -1) {
-            close(ret);
-            return -1;
-        }
-        qemu_set_cloexec(fds[1]);
-        return 0;
-    }
-
-    if (errno != ENOSYS) {
-        return -1;
-    }
-#endif
-
-    return qemu_pipe(fds);
-}
-
 int qemu_create_pidfile(const char *filename)
 {
     char buffer[128];
@@ -384,12 +351,3 @@ int qemu_create_pidfile(const char *filename)
     close(fd);
     return 0;
 }
-
-int qemu_get_thread_id(void)
-{
-#if defined (__linux__)
-    return syscall(SYS_gettid);
-#else
-    return getpid();
-#endif
-}

os-win32.c

@@ -151,8 +151,3 @@ int qemu_create_pidfile(const char *filename)
     }
     return 0;
 }
-
-int qemu_get_thread_id(void)
-{
-    return GetCurrentThreadId();
-}

oslib-posix.c

@@ -55,6 +55,21 @@ static int running_on_valgrind = -1;
 #else
 #  define running_on_valgrind 0
 #endif
+#ifdef CONFIG_LINUX
+#include <sys/syscall.h>
+#endif
+#ifdef CONFIG_EVENTFD
+#include <sys/eventfd.h>
+#endif
+
+int qemu_get_thread_id(void)
+{
+#if defined(__linux__)
+    return syscall(SYS_gettid);
+#else
+    return getpid();
+#endif
+}
 
 int qemu_daemon(int nochdir, int noclose)
 {
@@ -162,6 +177,34 @@ int qemu_pipe(int pipefd[2])
     return ret;
 }
 
+/*
+ * Creates an eventfd that looks like a pipe and has EFD_CLOEXEC set.
+ */
+int qemu_eventfd(int fds[2])
+{
+#ifdef CONFIG_EVENTFD
+    int ret;
+
+    ret = eventfd(0, 0);
+    if (ret >= 0) {
+        fds[0] = ret;
+        fds[1] = dup(ret);
+        if (fds[1] == -1) {
+            close(ret);
+            return -1;
+        }
+        qemu_set_cloexec(ret);
+        qemu_set_cloexec(fds[1]);
+        return 0;
+    }
+    if (errno != ENOSYS) {
+        return -1;
+    }
+#endif
+
+    return qemu_pipe(fds);
+}
+
 int qemu_utimens(const char *path, const struct timespec *times)
 {
     struct timeval tv[2], tv_now;

oslib-win32.c

@@ -118,3 +118,8 @@ int qemu_gettimeofday(qemu_timeval *tp)
      Do not set errno on error.  */
   return 0;
 }
+
+int qemu_get_thread_id(void)
+{
+    return GetCurrentThreadId();
+}

qemu-tool.c

@@ -16,12 +16,12 @@
 #include "qemu-timer.h"
 #include "qemu-log.h"
 #include "migration.h"
+#include "main-loop.h"
+#include "qemu_socket.h"
+#include "slirp/libslirp.h"
 
 #include <sys/time.h>
 
-QEMUClock *rt_clock;
-QEMUClock *vm_clock;
-
 FILE *logfile;
 
 struct QEMUBH
@@ -57,41 +57,45 @@ void monitor_protocol_event(MonitorEvent event, QObject *data)
 {
 }
 
-int qemu_set_fd_handler2(int fd,
-                         IOCanReadHandler *fd_read_poll,
-                         IOHandler *fd_read,
-                         IOHandler *fd_write,
-                         void *opaque)
+int64 cpu_get_clock(void)
 {
-    return 0;
+    abort();
 }
 
-void qemu_notify_event(void)
+int64 cpu_get_icount(void)
 {
+    abort();
 }
 
-QEMUTimer *qemu_new_timer(QEMUClock *clock, int scale,
-                          QEMUTimerCB *cb, void *opaque)
+void qemu_mutex_lock_iothread(void)
 {
-    return g_malloc(1);
 }
 
-void qemu_free_timer(QEMUTimer *ts)
+void qemu_mutex_unlock_iothread(void)
 {
-    g_free(ts);
 }
 
-void qemu_del_timer(QEMUTimer *ts)
+int use_icount;
+
+void qemu_clock_warp(QEMUClock *clock)
 {
 }
 
-void qemu_mod_timer(QEMUTimer *ts, int64_t expire_time)
+static void __attribute__((constructor)) init_main_loop(void)
 {
+    init_clocks();
+    init_timer_alarm();
+    qemu_clock_enable(vm_clock, false);
 }
 
-int64_t qemu_get_clock_ns(QEMUClock *clock)
+void slirp_select_fill(int *pnfds, fd_set *readfds,
+                       fd_set *writefds, fd_set *xfds)
+{
+}
+
+void slirp_select_poll(fd_set *readfds, fd_set *writefds,
+                       fd_set *xfds, int select_error)
 {
-    return 0;
 }
 
 void migrate_add_blocker(Error *reason)