Koraidon

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#include <fcntl.h>
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#include <stdio.h>
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#include <unistd.h>
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#include <sys/mman.h>
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#include "video/screen.h"
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void screen_debug_info(struct fb_var_screeninfo inf) {
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    printf("Width: %d\n", inf.width);
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    printf("Height: %d\n", inf.height);
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    printf("Sync: %X\n", inf.sync);
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    printf("Colorspace: %d\n", inf.colorspace);
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    printf("Grayscale: %d\n", inf.grayscale);
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    printf("BPP: %d\n", inf.bits_per_pixel);
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    printf("VMODE: %x\n", inf.vmode);
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    printf("R: %d\n", inf.red.offset);
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    printf("G: %d\n", inf.green.offset);
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    printf("B: %d\n", inf.blue.offset);
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    printf("Transp: %d\n", inf.transp.offset);
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}
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koraidon_screen_t init_screen(const char* path) {
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    koraidon_screen_t screen = {0};
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    struct fb_var_screeninfo* screen_info = &(screen.real_info);
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    int fd = open(path, O_RDWR);
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    screen.fd = fd;
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    if(fd < 0) {
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        printf("Could not open framebuffer: %s\n", path);
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        return invalid_screen;
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    }
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    ioctl(fd, FBIOGET_VSCREENINFO, &(screen.real_info));
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    size_t screen_size = screen_info->width * screen_info->height * (screen_info->bits_per_pixel >> 3);
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	printf("Screen size: %d\n", screen_size);
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    uint8_t* screendata = mmap(0, screen_size, PROT_READ | PROT_WRITE, MAP_SHARED, fd, 0);
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    if(!screendata) {
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        printf("mmap() failed\n");
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        return invalid_screen;
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    }
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    screen.ok = 1;
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    screen.buffer = screendata;
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    screen.screen_size = screen_size;
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    if(screen.real_info.red.offset == 16) {
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        screen.pixfmt = SCREEN_BGR;
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    } else {
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        screen.pixfmt = SCREEN_RGB;
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    }
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	printf("Pixfmt: %d\n", screen.pixfmt);
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    // Double-Flip our screen to fully initialize it.
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    screen.real_info.sync = !screen.real_info.sync;
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    ioctl(fd, FBIOPUT_VSCREENINFO, &(screen.real_info));
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    screen.real_info.sync = !screen.real_info.sync;
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    ioctl(fd, FBIOPUT_VSCREENINFO, &(screen.real_info));
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    screen_debug_info(screen.real_info);
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    return screen;
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}
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void deinit_screen(koraidon_screen_t screen) {
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    munmap(screen.buffer, screen.screen_size);
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    close(screen.fd);
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}