ui/console: replace kbd_timer with chr_accept_input callback

There's a ChardevClass chr_accept_input() callback function that
can replace the write retry timer.

Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Signed-off-by: Volker Rümelin <vr_qemu@t-online.de>
Message-Id: <20210916192239.18742-2-vr_qemu@t-online.de>
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>

ui/console.c

@@ -116,7 +116,6 @@ struct QemuConsole {
     Chardev *chr;
     /* fifo for key pressed */
     Fifo8 out_fifo;
-    QEMUTimer *kbd_timer;
     CoQueue dump_queue;
 
     QTAILQ_ENTRY(QemuConsole) next;
@@ -1106,30 +1105,21 @@ static int vc_chr_write(Chardev *chr, const uint8_t *buf, int len)
     return len;
 }
 
-static void kbd_send_chars(void *opaque)
+static void kbd_send_chars(QemuConsole *s)
 {
-    QemuConsole *s = opaque;
     uint32_t len, avail;
 
     len = qemu_chr_be_can_write(s->chr);
     avail = fifo8_num_used(&s->out_fifo);
-    if (len > avail) {
-        len = avail;
-    }
-    while (len > 0) {
+    while (len > 0 && avail > 0) {
         const uint8_t *buf;
         uint32_t size;
 
-        buf = fifo8_pop_buf(&s->out_fifo, len, &size);
+        buf = fifo8_pop_buf(&s->out_fifo, MIN(len, avail), &size);
         qemu_chr_be_write(s->chr, (uint8_t *)buf, size);
-        len -= size;
+        len = qemu_chr_be_can_write(s->chr);
         avail -= size;
     }
-    /* characters are pending: we send them a bit later (XXX:
-       horrible, should change char device API) */
-    if (avail > 0) {
-        timer_mod(s->kbd_timer, qemu_clock_get_ms(QEMU_CLOCK_REALTIME) + 1);
-    }
 }
 
 /* called when an ascii key is pressed */
@@ -2141,6 +2131,14 @@ int qemu_console_get_height(QemuConsole *con, int fallback)
     return con ? surface_height(con->surface) : fallback;
 }
 
+static void vc_chr_accept_input(Chardev *chr)
+{
+    VCChardev *drv = VC_CHARDEV(chr);
+    QemuConsole *s = drv->console;
+
+    kbd_send_chars(s);
+}
+
 static void vc_chr_set_echo(Chardev *chr, bool echo)
 {
     VCChardev *drv = VC_CHARDEV(chr);
@@ -2189,7 +2187,6 @@ static void text_console_do_init(Chardev *chr, DisplayState *ds)
     int g_height = 24 * FONT_HEIGHT;
 
     fifo8_create(&s->out_fifo, 16);
-    s->kbd_timer = timer_new_ms(QEMU_CLOCK_REALTIME, kbd_send_chars, s);
     s->ds = ds;
 
     s->y_displayed = 0;
@@ -2439,6 +2436,7 @@ static void char_vc_class_init(ObjectClass *oc, void *data)
     cc->parse = qemu_chr_parse_vc;
     cc->open = vc_chr_open;
     cc->chr_write = vc_chr_write;
+    cc->chr_accept_input = vc_chr_accept_input;
     cc->chr_set_echo = vc_chr_set_echo;
 }