Commit a7077b8e authored by Marc-André Lureau's avatar Marc-André Lureau
Browse files

chardev: use a child source for qio input source 



GLib child source were added with version 2.28. We can use them now
that we bumped our requirement to 2.40.

Signed-off-by: default avatarMarc-André Lureau <marcandre.lureau@redhat.com>
Reviewed-by: default avatarDaniel P. Berrangé <berrange@redhat.com>
parent 95e30b2a

chardev/char-io.c

+5 −43
Original line number Diff line number Diff line
@@ -33,7 +33,6 @@ typedef struct IOWatchPoll { 
    IOCanReadHandler *fd_can_read;

    GSourceFunc fd_read;

    void *opaque;

    GMainContext *context;

} IOWatchPoll;



static IOWatchPoll *io_watch_poll_from_source(GSource *source)
@@ -55,47 +54,24 @@ static gboolean io_watch_poll_prepare(GSource *source, 
        iwp->src = qio_channel_create_watch(

            iwp->ioc, G_IO_IN | G_IO_ERR | G_IO_HUP | G_IO_NVAL);

        g_source_set_callback(iwp->src, iwp->fd_read, iwp->opaque, NULL);

        g_source_attach(iwp->src, iwp->context);

    } else {

        g_source_destroy(iwp->src);

        g_source_add_child_source(source, iwp->src);

        g_source_unref(iwp->src);

    } else {

        g_source_remove_child_source(source, iwp->src);

        iwp->src = NULL;

    }

    return FALSE;

}



static gboolean io_watch_poll_check(GSource *source)

{

    return FALSE;

}



static gboolean io_watch_poll_dispatch(GSource *source, GSourceFunc callback,

                                       gpointer user_data)

{

    abort();

}



static void io_watch_poll_finalize(GSource *source)

{

    /* Due to a glib bug, removing the last reference to a source

     * inside a finalize callback causes recursive locking (and a

     * deadlock).  This is not a problem inside other callbacks,

     * including dispatch callbacks, so we call io_remove_watch_poll

     * to remove this source.  At this point, iwp->src must

     * be NULL, or we would leak it.

     *

     * This would be solved much more elegantly by child sources,

     * but we support older glib versions that do not have them.

     */

    IOWatchPoll *iwp = io_watch_poll_from_source(source);

    assert(iwp->src == NULL);

    return G_SOURCE_CONTINUE;

}



static GSourceFuncs io_watch_poll_funcs = {

    .prepare = io_watch_poll_prepare,

    .check = io_watch_poll_check,

    .dispatch = io_watch_poll_dispatch,

    .finalize = io_watch_poll_finalize,

};



GSource *io_add_watch_poll(Chardev *chr,
@@ -115,7 +91,6 @@ GSource *io_add_watch_poll(Chardev *chr, 
    iwp->ioc = ioc;

    iwp->fd_read = (GSourceFunc) fd_read;

    iwp->src = NULL;

    iwp->context = context;



    name = g_strdup_printf("chardev-iowatch-%s", chr->label);

    g_source_set_name((GSource *)iwp, name);
@@ -126,23 +101,10 @@ GSource *io_add_watch_poll(Chardev *chr, 
    return (GSource *)iwp;

}



static void io_remove_watch_poll(GSource *source)

{

    IOWatchPoll *iwp;



    iwp = io_watch_poll_from_source(source);

    if (iwp->src) {

        g_source_destroy(iwp->src);

        g_source_unref(iwp->src);

        iwp->src = NULL;

    }

    g_source_destroy(&iwp->parent);

}



void remove_fd_in_watch(Chardev *chr)

{

    if (chr->gsource) {

        io_remove_watch_poll(chr->gsource);

        g_source_destroy(chr->gsource);

        chr->gsource = NULL;

    }

}