qemu-char: add create to register_char_driver

Having creation as a member of the CharDriver struct removes the need
to export functions for qemu-char.c's usage.  After the conversion,
chardev backends implemented outside qemu-char.c will not need a stub
creation function anymore.

Ultimately all drivers will be converted.  For now, support the case
where cd->create == NULL.

Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

1 files changed, 3 insertions, 1 deletions

diff --git a/include/sysemu/char.h b/include/sysemu/char.h
index 832b7fe..4b01a8c 100644
--- a/include/sysemu/char.h
+++ b/include/sysemu/char.h
@@ -345,7 +345,9 @@ bool chr_is_ringbuf(const CharDriverState *chr);
 QemuOpts *qemu_chr_parse_compat(const char *label, const char *filename);
 
 void register_char_driver(const char *name, ChardevBackendKind kind,
-        void (*parse)(QemuOpts *opts, ChardevBackend *backend, Error **errp));
+        void (*parse)(QemuOpts *opts, ChardevBackend *backend, Error **errp),
+        CharDriverState *(*create)(const char *id, ChardevBackend *backend,
+                                   ChardevReturn *ret, Error **errp));
 
 /* add an eventfd to the qemu devices that are polled */
 CharDriverState *qemu_chr_open_eventfd(int eventfd);