chardev: qom-ify

Turn Chardev into Object.

qemu_chr_alloc() is replaced by the qemu_chardev_new() constructor. It
will call qemu_char_open() to open/intialize the chardev with the
ChardevCommon *backend settings.

The CharDriver::create() callback is turned into a ChardevClass::open()
which is called from the newly introduced qemu_chardev_open().

"chardev-gdb" and "chardev-hci" are internal chardev and aren't
creatable directly with -chardev. Use a new internal flag to disable
them. We may want to use TYPE_USER_CREATABLE interface instead, or
perhaps allow -chardev usage.

Although in general we keep typename and macros private, unless the type
is being used by some other file, in this patch, all types and common
helper macros for qemu-char.c are in char.h. This is to help transition
now (some types must be declared early, while some aren't shared) and
when splitting in several units. This is to be improved later.

Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

3 files changed, 82 insertions, 75 deletions

diff --git a/backends/baum.c b/backends/baum.c
index 8842936417..0f418ed358 100644
--- a/backends/baum.c
+++ b/backends/baum.c
@@ -100,6 +100,9 @@ typedef struct {
     QEMUTimer *cellCount_timer;
 } BaumChardev;
 
+#define TYPE_CHARDEV_BRAILLE "chardev-braille"
+#define BAUM_CHARDEV(obj) OBJECT_CHECK(BaumChardev, (obj), TYPE_CHARDEV_BRAILLE)
+
 /* Let's assume NABCC by default */
 enum way {
     DOTS2ASCII,
@@ -255,7 +258,7 @@ static int baum_deferred_init(BaumChardev *baum)
 /* The serial port can receive more of our data */
 static void baum_chr_accept_input(struct Chardev *chr)
 {
-    BaumChardev *baum = (BaumChardev *)chr;
+    BaumChardev *baum = BAUM_CHARDEV(chr);
     int room, first;
 
     if (!baum->out_buf_used)
@@ -281,7 +284,7 @@ static void baum_chr_accept_input(struct Chardev *chr)
 /* We want to send a packet */
 static void baum_write_packet(BaumChardev *baum, const uint8_t *buf, int len)
 {
-    Chardev *chr = (Chardev *)baum;
+    Chardev *chr = CHARDEV(baum);
     uint8_t io_buf[1 + 2 * len], *cur = io_buf;
     int room;
     *cur++ = ESC;
@@ -322,7 +325,7 @@ static void baum_write_packet(BaumChardev *baum, const uint8_t *buf, int len)
 /* Called when the other end seems to have a wrong idea of our display size */
 static void baum_cellCount_timer_cb(void *opaque)
 {
-    BaumChardev *baum = opaque;
+    BaumChardev *baum = BAUM_CHARDEV(opaque);
     uint8_t cell_count[] = { BAUM_RSP_CellCount, baum->x * baum->y };
     DPRINTF("Timeout waiting for DisplayData, sending cell count\n");
     baum_write_packet(baum, cell_count, sizeof(cell_count));
@@ -472,7 +475,7 @@ static int baum_eat_packet(BaumChardev *baum, const uint8_t *buf, int len)
 /* The other end is writing some data.  Store it and try to interpret */
 static int baum_chr_write(Chardev *chr, const uint8_t *buf, int len)
 {
-    BaumChardev *baum = (BaumChardev *)chr;
+    BaumChardev *baum = BAUM_CHARDEV(chr);
     int tocopy, cur, eaten, orig_len = len;
 
     if (!len)
@@ -529,7 +532,7 @@ static void baum_send_key2(BaumChardev *baum, uint8_t type, uint8_t value,
 /* We got some data on the BrlAPI socket */
 static void baum_chr_read(void *opaque)
 {
-    BaumChardev *baum = opaque;
+    BaumChardev *baum = BAUM_CHARDEV(opaque);
     brlapi_keyCode_t code;
     int ret;
     if (!baum->brlapi)
@@ -613,9 +616,9 @@ static void baum_chr_read(void *opaque)
     }
 }
 
-static void baum_chr_free(struct Chardev *chr)
+static void baum_chr_free(Chardev *chr)
 {
-    BaumChardev *baum = (BaumChardev *)chr;
+    BaumChardev *baum = BAUM_CHARDEV(chr);
 
     timer_free(baum->cellCount_timer);
     if (baum->brlapi) {
@@ -624,24 +627,14 @@ static void baum_chr_free(struct Chardev *chr)
     }
 }
 
-static Chardev *baum_chr_init(const CharDriver *driver,
-                              const char *id,
-                              ChardevBackend *backend,
-                              ChardevReturn *ret,
-                              bool *be_opened,
-                              Error **errp)
+static void baum_chr_open(Chardev *chr,
+                          ChardevBackend *backend,
+                          bool *be_opened,
+                          Error **errp)
 {
-    ChardevCommon *common = backend->u.braille.data;
-    BaumChardev *baum;
-    Chardev *chr;
+    BaumChardev *baum = BAUM_CHARDEV(chr);
     brlapi_handle_t *handle;
 
-    chr = qemu_chr_alloc(driver, common, errp);
-    if (!chr) {
-        return NULL;
-    }
-    baum = (BaumChardev *)chr;
-
     handle = g_malloc0(brlapi_getHandleSize());
     baum->brlapi = handle;
 
@@ -649,34 +642,41 @@ static Chardev *baum_chr_init(const CharDriver *driver,
     if (baum->brlapi_fd == -1) {
         error_setg(errp, "brlapi__openConnection: %s",
                    brlapi_strerror(brlapi_error_location()));
-        goto fail_handle;
+        g_free(handle);
+        return;
     }
     baum->deferred_init = 0;
 
     baum->cellCount_timer = timer_new_ns(QEMU_CLOCK_VIRTUAL, baum_cellCount_timer_cb, baum);
 
     qemu_set_fd_handler(baum->brlapi_fd, baum_chr_read, NULL, baum);
+}
 
-    return chr;
+static void char_braille_class_init(ObjectClass *oc, void *data)
+{
+    ChardevClass *cc = CHARDEV_CLASS(oc);
 
-fail_handle:
-    g_free(handle);
-    g_free(chr);
-    return NULL;
+    cc->open = baum_chr_open;
+    cc->chr_write = baum_chr_write;
+    cc->chr_accept_input = baum_chr_accept_input;
+    cc->chr_free = baum_chr_free;
 }
 
+static const TypeInfo char_braille_type_info = {
+    .name = TYPE_CHARDEV_BRAILLE,
+    .parent = TYPE_CHARDEV,
+    .instance_size = sizeof(BaumChardev),
+    .class_init = char_braille_class_init,
+};
+
 static void register_types(void)
 {
     static const CharDriver driver = {
-        .instance_size = sizeof(BaumChardev),
         .kind = CHARDEV_BACKEND_KIND_BRAILLE,
-        .create = baum_chr_init,
-        .chr_write = baum_chr_write,
-        .chr_accept_input = baum_chr_accept_input,
-        .chr_free = baum_chr_free,
     };
 
     register_char_driver(&driver);
+    type_register_static(&char_braille_type_info);
 }
 
 type_init(register_types);
diff --git a/backends/msmouse.c b/backends/msmouse.c
index 4e474da4c3..936a5476d5 100644
--- a/backends/msmouse.c
+++ b/backends/msmouse.c
@@ -41,9 +41,13 @@ typedef struct {
     int outlen;
 } MouseChardev;
 
+#define TYPE_CHARDEV_MSMOUSE "chardev-msmouse"
+#define MOUSE_CHARDEV(obj)                                      \
+    OBJECT_CHECK(MouseChardev, (obj), TYPE_CHARDEV_MSMOUSE)
+
 static void msmouse_chr_accept_input(Chardev *chr)
 {
-    MouseChardev *mouse = (MouseChardev *)chr;
+    MouseChardev *mouse = MOUSE_CHARDEV(chr);
     int len;
 
     len = qemu_chr_be_can_write(chr);
@@ -98,7 +102,7 @@ static void msmouse_queue_event(MouseChardev *mouse)
 static void msmouse_input_event(DeviceState *dev, QemuConsole *src,
                                 InputEvent *evt)
 {
-    MouseChardev *mouse = (MouseChardev *)dev;
+    MouseChardev *mouse = MOUSE_CHARDEV(dev);
     InputMoveEvent *move;
     InputBtnEvent *btn;
 
@@ -122,8 +126,8 @@ static void msmouse_input_event(DeviceState *dev, QemuConsole *src,
 
 static void msmouse_input_sync(DeviceState *dev)
 {
-    MouseChardev *mouse = (MouseChardev *)dev;
-    Chardev *chr = (Chardev *)dev;
+    MouseChardev *mouse = MOUSE_CHARDEV(dev);
+    Chardev *chr = CHARDEV(dev);
 
     msmouse_queue_event(mouse);
     msmouse_chr_accept_input(chr);
@@ -137,7 +141,7 @@ static int msmouse_chr_write(struct Chardev *s, const uint8_t *buf, int len)
 
 static void msmouse_chr_free(struct Chardev *chr)
 {
-    MouseChardev *mouse = (MouseChardev *)chr;
+    MouseChardev *mouse = MOUSE_CHARDEV(chr);
 
     qemu_input_handler_unregister(mouse->hs);
 }
@@ -149,42 +153,43 @@ static QemuInputHandler msmouse_handler = {
     .sync  = msmouse_input_sync,
 };
 
-static Chardev *qemu_chr_open_msmouse(const CharDriver *driver,
-                                      const char *id,
-                                      ChardevBackend *backend,
-                                      ChardevReturn *ret,
-                                      bool *be_opened,
-                                      Error **errp)
+static void msmouse_chr_open(Chardev *chr,
+                             ChardevBackend *backend,
+                             bool *be_opened,
+                             Error **errp)
 {
-    ChardevCommon *common = backend->u.msmouse.data;
-    MouseChardev *mouse;
-    Chardev *chr;
+    MouseChardev *mouse = MOUSE_CHARDEV(chr);
 
-    chr = qemu_chr_alloc(driver, common, errp);
-    if (!chr) {
-        return NULL;
-    }
     *be_opened = false;
-
-    mouse = (MouseChardev *)chr;
     mouse->hs = qemu_input_handler_register((DeviceState *)mouse,
                                             &msmouse_handler);
+}
 
+static void char_msmouse_class_init(ObjectClass *oc, void *data)
+{
+    ChardevClass *cc = CHARDEV_CLASS(oc);
 
-    return chr;
+    cc->open = msmouse_chr_open;
+    cc->chr_write = msmouse_chr_write;
+    cc->chr_accept_input = msmouse_chr_accept_input;
+    cc->chr_free = msmouse_chr_free;
 }
 
+static const TypeInfo char_msmouse_type_info = {
+    .name = TYPE_CHARDEV_MSMOUSE,
+    .parent = TYPE_CHARDEV,
+    .instance_size = sizeof(MouseChardev),
+    .class_init = char_msmouse_class_init,
+};
+
 static void register_types(void)
 {
     static const CharDriver driver = {
-        .instance_size = sizeof(MouseChardev),
         .kind = CHARDEV_BACKEND_KIND_MSMOUSE,
-        .create = qemu_chr_open_msmouse,
-        .chr_write = msmouse_chr_write,
-        .chr_accept_input = msmouse_chr_accept_input,
-        .chr_free = msmouse_chr_free,
     };
+
     register_char_driver(&driver);
+    type_register_static(&char_msmouse_type_info);
 }
 
 type_init(register_types);
diff --git a/backends/testdev.c b/backends/testdev.c
index 268b380cf3..ea15143713 100644
--- a/backends/testdev.c
+++ b/backends/testdev.c
@@ -36,6 +36,10 @@ typedef struct {
     int in_buf_used;
 } TestdevChardev;
 
+#define TYPE_CHARDEV_TESTDEV "chardev-testdev"
+#define TESTDEV_CHARDEV(obj)                                    \
+    OBJECT_CHECK(TestdevChardev, (obj), TYPE_CHARDEV_TESTDEV)
+
 /* Try to interpret a whole incoming packet */
 static int testdev_eat_packet(TestdevChardev *testdev)
 {
@@ -78,9 +82,9 @@ static int testdev_eat_packet(TestdevChardev *testdev)
 }
 
 /* The other end is writing some data.  Store it and try to interpret */
-static int testdev_write(Chardev *chr, const uint8_t *buf, int len)
+static int testdev_chr_write(Chardev *chr, const uint8_t *buf, int len)
 {
-    TestdevChardev *testdev = (TestdevChardev *)chr;
+    TestdevChardev *testdev = TESTDEV_CHARDEV(chr);
     int tocopy, eaten, orig_len = len;
 
     while (len) {
@@ -103,30 +107,28 @@ static int testdev_write(Chardev *chr, const uint8_t *buf, int len)
     return orig_len;
 }
 
-static Chardev *chr_testdev_init(const CharDriver *driver,
-                                 const char *id,
-                                 ChardevBackend *backend,
-                                 ChardevReturn *ret,
-                                 bool *be_opened,
-                                 Error **errp)
+static void char_testdev_class_init(ObjectClass *oc, void *data)
 {
-    TestdevChardev *testdev = g_new0(TestdevChardev, 1);;
-    Chardev *chr = (Chardev *)testdev;
-
-    chr->driver = driver;
+    ChardevClass *cc = CHARDEV_CLASS(oc);
 
-    return chr;
+    cc->chr_write = testdev_chr_write;
 }
 
+static const TypeInfo char_testdev_type_info = {
+    .name = TYPE_CHARDEV_TESTDEV,
+    .parent = TYPE_CHARDEV,
+    .instance_size = sizeof(TestdevChardev),
+    .class_init = char_testdev_class_init,
+};
+
 static void register_types(void)
 {
     static const CharDriver driver = {
-        .instance_size = sizeof(TestdevChardev),
         .kind = CHARDEV_BACKEND_KIND_TESTDEV,
-        .create = chr_testdev_init,
-        .chr_write = testdev_write,
     };
+
     register_char_driver(&driver);
+    type_register_static(&char_testdev_type_info);
 }
 
 type_init(register_types);