On 02/23/2018 07:04 AM, Marek Vasut wrote:
On 02/23/2018 06:50 AM, Heinrich Schuchardt wrote:
[...]
When starting an EFI application the xterm escape sequences are
translated to EFI scan codes. See lib/efi_loader/efi_console.c

So this is only usable if you have display connected to the board ?

Why? We are talking about input.

Neither local nor remote display is needed to hit the F10 key on a USB
keyboard.

What confused me was the constant usage of xterm control sequences to
describe terminal control sequences. Now it makes sense.

[...]

+    /* Copy to buffer */
+    for (i = 0; i < count; ++i) {
+        ++data->usb_in_pointer;
+        if (data->usb_in_pointer == USB_KBD_BUFFER_LEN)
+            data->usb_in_pointer = 0;
+        data->usb_kbd_buffer[data->usb_in_pointer] = buf[i];

memcpy() ?

Typically we copy only one byte. But escape sequences have a maximum
length of 8 bytes (e.g. CTRL+F8).

We have to consider the case with wrap around. This would require two
memcpy() calls.

The coding would neither get faster in the average nor less complex
using memcpy(). So let's keep it as it is.

I suspect this block of code needs cleanup .


Could you, please, give some indication of what you dislike.

At least the part which looks like ad-hoc implementation of memcpy() ,
any other cleanups are welcome.


Do you really want that ugly monster below for typically copying a
single byte?

As said it is slower, has more lines, and gives a larger executable.

int remaining;

/* Copy to buffer */
remaining = data->usb_in_pointer + count - USB_KBD_BUFFER_LEN;
if (remaining < 0)
     remaining = 0;
memcpy(&usb_kbd_buffer[data->usb_in_pointer], buf, count - remaining);
if (remaining)
     memcpy(usb_kbd_buffer, buf + count - remaining, remaining);
data->usb_in_pointer += count;
if (data->usb_in_pointer >= USB_KBD_BUFFER_LEN)
     data->usb_in_pointer -= USB_KBD_BUFFER_LEN;

Can the code be tweaked so it doesn't use the circular buffer, but a
linear one , thus two memcpy()s are not needed ?

This would require copying the whole buffer with memcpy() when withdrawing a byte.

Somehow we tend to reinvent the wheel. Let's use lib/circbuf.c here.

Regards

Heinrich


The whole usb keyboard code is not nice and could use some cleanup.

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