kvisc/vm/pc/keybd.c

// The OS/K Team licenses this file to you under the MIT license.
// See the LICENSE file in the project root for more information.

#include <pc/console.h>

#define KEYBUFSIZE      8192

typedef uint keycode_t;

keycode_t keybuf[KEYBUFSIZE] = { 0 };
keycode_t *keybuf_last = &keybuf[0];
keycode_t *keybuf_ptr = &keybuf[0];

void console_addkey(ctx_t *ctx, keycode_t key)
{
    *keybuf_ptr++ = key;

    if (keybuf_ptr == keybuf + KEYBUFSIZE)
        keybuf_ptr = &keybuf[0];
}

keycode_t console_getkey(ctx_t *ctx)
{
    keycode_t rc = *keybuf_last++;

    if (keybuf_last == keybuf + KEYBUFSIZE)
        keybuf_last = &keybuf[0];

    return rc;
}

keycode_t console_scankeybuf(ctx_t *ctx)
{
    if (keybuf_last != keybuf_ptr)
        return console_getkey(ctx);

    return 0;
}

void console_handle_input(ctx_t *ctx, SDL_Keycode key)
{
    keycode_t code = 0;

    SDL_Keymod mod = SDL_GetModState();

    if (key <= 'z' && key >= 'a')
    {
        if (mod & (KMOD_CTRL|KMOD_ALT))
        {
            if (key == 'c')
                _except(ctx, E_BRK, "Ctrl+C received");

            return;
        }

        if (mod & KMOD_SHIFT)
            key -= ('a' - 'A');

        console_addkey(ctx, key);

        return;
    }

    if (key <= '0' && key >= '9')
        console_addkey(ctx, key);

    switch (key)
    {
        case SDLK_SPACE:        code = ' ';     break;
        case SDLK_BACKSLASH:    code = '\\';    break;
        case SDLK_BACKSPACE:    code = '\b';    break;

        case SDLK_RETURN:
        case SDLK_RETURN2:
            code = '\n';
            break;

        default:
            return;
    }

    console_addkey(ctx, code);
}