Hey Hans,
On Fri, 2018-06-29 at 09:03 +0200, Hans Verkuil wrote:
> On 06/28/2018 09:25 PM, Ezequiel Garcia wrote:
> > When creating a second node via copy or assignment:
> >
> > node2 = node
> >
> > The node being assigned to, i.e. node2, obtains the fd.
> > This causes a later call to node2.media_open to close()
> > the fd, thus unintendenly closing the original node fd,
> > via the call path (e.g. for media devices):
> >
> > node2.media_open
> > v4l_media_open
> > v4l_media_s_fd
> >
> > Similar call paths apply for other device types.
> > Fix this by removing the close in xxx_s_fd.
>
> I fixed this in a different way by overloading the assignment
> operator
> and calling dup(fd). That solves this as well.
>
This patch is also needed to prevent the compliance tool
from unintendenly closing a descriptor.
diff --git a/utils/common/v4l-helpers.h b/utils/common/v4l-helpers.h
index 27683a3d286d..45ed997379a1 100644
--- a/utils/common/v4l-helpers.h
+++ b/utils/common/v4l-helpers.h
@@ -118,7 +118,11 @@ static inline int v4l_wrap_open(struct v4l_fd *f,
const char *file, int oflag, .
static inline int v4l_wrap_close(struct v4l_fd *f)
{
- return close(f->fd);
+ int ret;
+
+ ret = close(f->fd);
+ f->fd = -1;
+ return ret;
}
static inline ssize_t v4l_wrap_read(struct v4l_fd *f, void *buffer,
size_t n)
Regards,
Eze
