[02/13] char: Add ChardevOptions and qemu_chr_new_cli()

Commit Message

Kevin Wolf Nov. 12, 2020, 5:58 p.m. UTC

This provides an interface to create a chardev from a QAPI
representation of the command line.

At this point, the only difference between it and QMP chardev-add is
that it allows 'backend' to be flattened and returns a Chardev pointer.
We'll add support for mux=on and more compatibility glue to support
legacy command line syntax later.

Signed-off-by: Kevin Wolf <[e-mail]>
---
 qapi/char.json         | 15 +++++++++++++++
 include/chardev/char.h |  9 +++++++++
 chardev/char.c         | 24 ++++++++++++++++++------
 3 files changed, 42 insertions(+), 6 deletions(-)

Patch

diff --git a/qapi/char.json b/qapi/char.json
index 43486d1daa..14ee06a52d 100644
--- a/qapi/char.json
+++ b/qapi/char.json
@@ -435,6 +435,21 @@ 
 { 'struct' : 'ChardevReturn',
   'data': { '*pty': 'str' } }
 
+##
+# @ChardevOptions:
+#
+# Command line options for creating a character device backend
+#
+# @id: the chardev's ID, must be unique
+# @backend: backend type and parameters
+#
+# Since: 6.0
+##
+{ 'struct': 'ChardevOptions',
+  'data': { 'id': 'str',
+            'backend': 'ChardevBackend' },
+  'aliases': [ { 'source': ['backend'] } ] }
+
 ##
 # @chardev-add:
 #
diff --git a/include/chardev/char.h b/include/chardev/char.h
index 3b91645081..54fa2ed8e2 100644
--- a/include/chardev/char.h
+++ b/include/chardev/char.h
@@ -85,6 +85,15 @@  Chardev *qemu_chr_new_from_opts(QemuOpts *opts,
                                 GMainContext *context,
                                 Error **errp);
 
+/**
+ * qemu_chr_new_cli:
+ * @options: Character device creation options as defined in QAPI
+ *
+ * Returns: on success: a new character backend
+ *          otherwise:  NULL; @errp specifies the error
+ */
+Chardev *qemu_chr_new_cli(ChardevOptions *options, Error **errp);
+
 /**
  * qemu_chr_parse_common:
  * @opts: the options that still need parsing
diff --git a/chardev/char.c b/chardev/char.c
index de39e2d79b..9f00e475d4 100644
--- a/chardev/char.c
+++ b/chardev/char.c
@@ -1037,20 +1037,27 @@  Chardev *qemu_chardev_new(const char *id, const char *typename,
     return chardev_new(id, typename, backend, gcontext, errp);
 }
 
-ChardevReturn *qmp_chardev_add(const char *id, ChardevBackend *backend,
-                               Error **errp)
+static Chardev *chardev_new_qapi(const char *id, ChardevBackend *backend,
+                                 Error **errp)
 {
     const ChardevClass *cc;
-    ChardevReturn *ret;
-    Chardev *chr;
 
     cc = char_get_class(ChardevBackendKind_str(backend->type), errp);
     if (!cc) {
         return NULL;
     }
 
-    chr = chardev_new(id, object_class_get_name(OBJECT_CLASS(cc)),
-                      backend, NULL, errp);
+    return chardev_new(id, object_class_get_name(OBJECT_CLASS(cc)),
+                       backend, NULL, errp);
+}
+
+ChardevReturn *qmp_chardev_add(const char *id, ChardevBackend *backend,
+                               Error **errp)
+{
+    ChardevReturn *ret;
+    Chardev *chr;
+
+    chr = chardev_new_qapi(id, backend, errp);
     if (!chr) {
         return NULL;
     }
@@ -1064,6 +1071,11 @@  ChardevReturn *qmp_chardev_add(const char *id, ChardevBackend *backend,
     return ret;
 }
 
+Chardev *qemu_chr_new_cli(ChardevOptions *options, Error **errp)
+{
+    return chardev_new_qapi(options->id, options->backend, errp);
+}
+
 ChardevReturn *qmp_chardev_change(const char *id, ChardevBackend *backend,
                                   Error **errp)
 {