util: merge main-loop.c and iohandler.c

main-loop.c has a dependency on iohandler.c, and everything breaks
if that dependency is instead satisfied by stubs/iohandler.c.
Just put everything in the same file to avoid strange dependencies
on the order of files in util-obj-y.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Message-Id: <1562952875-53702-1-git-send-email-pbonzini@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

1 files changed, 110 insertions, 0 deletions

diff --git a/util/main-loop.c b/util/main-loop.c
index a9f4e8d..e3eaa55 100644
--- a/util/main-loop.c
+++ b/util/main-loop.c
@@ -32,6 +32,11 @@
 #include "qemu/main-loop.h"
 #include "block/aio.h"
 #include "qemu/error-report.h"
+#include "qemu/queue.h"
+
+#ifndef _WIN32
+#include <sys/wait.h>
+#endif
 
 #ifndef _WIN32
 
@@ -525,3 +530,108 @@ QEMUBH *qemu_bh_new(QEMUBHFunc *cb, void *opaque)
 {
     return aio_bh_new(qemu_aio_context, cb, opaque);
 }
+
+/*
+ * Functions to operate on the I/O handler AioContext.
+ * This context runs on top of main loop. We can't reuse qemu_aio_context
+ * because iohandlers mustn't be polled by aio_poll(qemu_aio_context).
+ */
+static AioContext *iohandler_ctx;
+
+static void iohandler_init(void)
+{
+    if (!iohandler_ctx) {
+        iohandler_ctx = aio_context_new(&error_abort);
+    }
+}
+
+AioContext *iohandler_get_aio_context(void)
+{
+    iohandler_init();
+    return iohandler_ctx;
+}
+
+GSource *iohandler_get_g_source(void)
+{
+    iohandler_init();
+    return aio_get_g_source(iohandler_ctx);
+}
+
+void qemu_set_fd_handler(int fd,
+                         IOHandler *fd_read,
+                         IOHandler *fd_write,
+                         void *opaque)
+{
+    iohandler_init();
+    aio_set_fd_handler(iohandler_ctx, fd, false,
+                       fd_read, fd_write, NULL, opaque);
+}
+
+void event_notifier_set_handler(EventNotifier *e,
+                                EventNotifierHandler *handler)
+{
+    iohandler_init();
+    aio_set_event_notifier(iohandler_ctx, e, false,
+                           handler, NULL);
+}
+
+/* reaping of zombies.  right now we're not passing the status to
+   anyone, but it would be possible to add a callback.  */
+#ifndef _WIN32
+typedef struct ChildProcessRecord {
+    int pid;
+    QLIST_ENTRY(ChildProcessRecord) next;
+} ChildProcessRecord;
+
+static QLIST_HEAD(, ChildProcessRecord) child_watches =
+    QLIST_HEAD_INITIALIZER(child_watches);
+
+static QEMUBH *sigchld_bh;
+
+static void sigchld_handler(int signal)
+{
+    qemu_bh_schedule(sigchld_bh);
+}
+
+static void sigchld_bh_handler(void *opaque)
+{
+    ChildProcessRecord *rec, *next;
+
+    QLIST_FOREACH_SAFE(rec, &child_watches, next, next) {
+        if (waitpid(rec->pid, NULL, WNOHANG) == rec->pid) {
+            QLIST_REMOVE(rec, next);
+            g_free(rec);
+        }
+    }
+}
+
+static void qemu_init_child_watch(void)
+{
+    struct sigaction act;
+    sigchld_bh = qemu_bh_new(sigchld_bh_handler, NULL);
+
+    memset(&act, 0, sizeof(act));
+    act.sa_handler = sigchld_handler;
+    act.sa_flags = SA_NOCLDSTOP;
+    sigaction(SIGCHLD, &act, NULL);
+}
+
+int qemu_add_child_watch(pid_t pid)
+{
+    ChildProcessRecord *rec;
+
+    if (!sigchld_bh) {
+        qemu_init_child_watch();
+    }
+
+    QLIST_FOREACH(rec, &child_watches, next) {
+        if (rec->pid == pid) {
+            return 1;
+        }
+    }
+    rec = g_malloc0(sizeof(ChildProcessRecord));
+    rec->pid = pid;
+    QLIST_INSERT_HEAD(&child_watches, rec, next);
+    return 0;
+}
+#endif