io: Introduce qio_channel_file_new_dupfd

Add a new helper function for creating a QIOChannelFile channel with a
duplicated file descriptor. This saves the calling code from having to
do error checking on the dup() call.

Suggested-by: "Daniel P. Berrangé" <berrange@redhat.com>
Signed-off-by: Fabiano Rosas <farosas@suse.de>
Reviewed-by: "Daniel P. Berrangé" <berrange@redhat.com>
Link: https://lore.kernel.org/r/20240311233335.17299-2-farosas@suse.de
Signed-off-by: Peter Xu <peterx@redhat.com>

1 files changed, 18 insertions, 0 deletions

diff --git a/include/io/channel-file.h b/include/io/channel-file.h
index 50e8eb1138..d373a4e44d 100644
--- a/include/io/channel-file.h
+++ b/include/io/channel-file.h
@@ -69,6 +69,24 @@ QIOChannelFile *
 qio_channel_file_new_fd(int fd);
 
 /**
+ * qio_channel_file_new_dupfd:
+ * @fd: the file descriptor
+ * @errp: pointer to initialized error object
+ *
+ * Create a new IO channel object for a file represented by the @fd
+ * parameter. Like qio_channel_file_new_fd(), but the @fd is first
+ * duplicated with dup().
+ *
+ * The channel will own the duplicated file descriptor and will take
+ * responsibility for closing it, the original FD is owned by the
+ * caller.
+ *
+ * Returns: the new channel object
+ */
+QIOChannelFile *
+qio_channel_file_new_dupfd(int fd, Error **errp);
+
+/**
  * qio_channel_file_new_path:
  * @path: the file path
  * @flags: the open flags (O_RDONLY|O_WRONLY|O_RDWR, etc)