Hi
On Thu, Sep 8, 2022 at 9:38 PM Arwed Meyer <arwed.me...@gmx.de> wrote:
> Make use of fifo8 functions instead of implementing own fifo code.
> This makes the code more readable and reduces risk of bugs.
>
> Signed-off-by: Arwed Meyer <arwed.me...@gmx.de>
>
Reviewed-by: Marc-André Lureau <marcandre.lur...@redhat.com>
> ---
> chardev/msmouse.c | 43 +++++++++++++++++++++----------------------
> 1 file changed, 21 insertions(+), 22 deletions(-)
>
> diff --git a/chardev/msmouse.c b/chardev/msmouse.c
> index 95fa488339..e9aa3eab55 100644
> --- a/chardev/msmouse.c
> +++ b/chardev/msmouse.c
> @@ -24,6 +24,7 @@
>
> #include "qemu/osdep.h"
> #include "qemu/module.h"
> +#include "qemu/fifo8.h"
> #include "chardev/char.h"
> #include "chardev/char-serial.h"
> #include "ui/console.h"
> @@ -34,6 +35,12 @@
> #define MSMOUSE_HI2(n) (((n) & 0xc0) >> 6)
> #define MSMOUSE_PWR(cm) (cm & (CHR_TIOCM_RTS | CHR_TIOCM_DTR))
>
> +/* Serial fifo size. */
> +#define MSMOUSE_BUF_SZ 64
>
Why bump to 64 bytes?
> +
> +/* Mouse ID: Send "M3" cause we behave like a 3 button logitech mouse. */
> +const uint8_t mouse_id[] = {'M', '3'};
> +
> struct MouseChardev {
> Chardev parent;
>
> @@ -42,8 +49,7 @@ struct MouseChardev {
> int axis[INPUT_AXIS__MAX];
> bool btns[INPUT_BUTTON__MAX];
> bool btnc[INPUT_BUTTON__MAX];
> - uint8_t outbuf[32];
> - int outlen;
> + Fifo8 outbuf;
> };
> typedef struct MouseChardev MouseChardev;
>
> @@ -54,21 +60,15 @@ DECLARE_INSTANCE_CHECKER(MouseChardev, MOUSE_CHARDEV,
> static void msmouse_chr_accept_input(Chardev *chr)
> {
> MouseChardev *mouse = MOUSE_CHARDEV(chr);
> - int len;
> + uint32_t len_out, len;
>
> - len = qemu_chr_be_can_write(chr);
> - if (len > mouse->outlen) {
> - len = mouse->outlen;
> - }
> - if (!len) {
> + len_out = qemu_chr_be_can_write(chr);
> + if (!len_out || fifo8_is_empty(&mouse->outbuf)) {
> return;
> }
> -
> - qemu_chr_be_write(chr, mouse->outbuf, len);
> - mouse->outlen -= len;
> - if (mouse->outlen) {
> - memmove(mouse->outbuf, mouse->outbuf + len, mouse->outlen);
> - }
> + len = MIN(fifo8_num_used(&mouse->outbuf), len_out);
> + qemu_chr_be_write(chr, fifo8_pop_buf(&mouse->outbuf, len, &len_out),
> + len_out);
> }
>
> static void msmouse_queue_event(MouseChardev *mouse)
> @@ -94,12 +94,11 @@ static void msmouse_queue_event(MouseChardev *mouse)
> mouse->btnc[INPUT_BUTTON_MIDDLE]) {
> bytes[3] |= (mouse->btns[INPUT_BUTTON_MIDDLE] ? 0x20 : 0x00);
> mouse->btnc[INPUT_BUTTON_MIDDLE] = false;
> - count = 4;
> + count++;
>
a bit superfluous, ok
}
>
> - if (mouse->outlen <= sizeof(mouse->outbuf) - count) {
> - memcpy(mouse->outbuf + mouse->outlen, bytes, count);
> - mouse->outlen += count;
> + if (fifo8_num_free(&mouse->outbuf) >= count) {
> + fifo8_push_all(&mouse->outbuf, bytes, count);
> } else {
> /* queue full -> drop event */
> }
> @@ -172,9 +171,7 @@ static int msmouse_ioctl(Chardev *chr, int cmd, void
> *arg)
> * cause we behave like a 3 button logitech
> * mouse.
> */
> - mouse->outbuf[0] = 'M';
> - mouse->outbuf[1] = '3';
> - mouse->outlen = 2;
> + fifo8_push_all(&mouse->outbuf, mouse_id,
> sizeof(mouse_id));
> /* Start sending data to serial. */
> msmouse_chr_accept_input(chr);
> }
> @@ -184,7 +181,7 @@ static int msmouse_ioctl(Chardev *chr, int cmd, void
> *arg)
> * Reset mouse buffers on power down.
> * Mouse won't send anything without power.
> */
> - mouse->outlen = 0;
> + fifo8_reset(&mouse->outbuf);
> memset(mouse->axis, 0, sizeof(mouse->axis));
> memset(mouse->btns, false, sizeof(mouse->btns));
> memset(mouse->btnc, false, sizeof(mouse->btns));
> @@ -204,6 +201,7 @@ static void char_msmouse_finalize(Object *obj)
> MouseChardev *mouse = MOUSE_CHARDEV(obj);
>
> qemu_input_handler_unregister(mouse->hs);
> + fifo8_destroy(&mouse->outbuf);
> }
>
> static QemuInputHandler msmouse_handler = {
> @@ -224,6 +222,7 @@ static void msmouse_chr_open(Chardev *chr,
> mouse->hs = qemu_input_handler_register((DeviceState *)mouse,
> &msmouse_handler);
> mouse->tiocm = 0;
> + fifo8_create(&mouse->outbuf, MSMOUSE_BUF_SZ);
> }
>
> static void char_msmouse_class_init(ObjectClass *oc, void *data)
> --
> 2.34.1
>
>
>
--
Marc-André Lureau
