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authorHunter Kvalevog <hunter@kvog.sh>2026-02-15 18:48:59 -0600
committerHunter Kvalevog <hunter@kvog.sh>2026-02-15 18:48:59 -0600
commit7d7f38fed94e50c0a8427cb814cb996a472219a2 (patch)
tree4b06d8d1dbde8c9b0f34fba0acb63a484ea7bd5d /rushmore-linux/rlws
parent0f6104b8a5d50c87c8f3f1ab4ec62e0dd1bf3704 (diff)
rlws -> rltest
Diffstat (limited to 'rushmore-linux/rlws')
-rw-r--r--rushmore-linux/rlws/rlws.c125
1 files changed, 0 insertions, 125 deletions
diff --git a/rushmore-linux/rlws/rlws.c b/rushmore-linux/rlws/rlws.c
deleted file mode 100644
index 719ffba..0000000
--- a/rushmore-linux/rlws/rlws.c
+++ /dev/null
@@ -1,125 +0,0 @@
-#include <errno.h>
-#include <fcntl.h>
-#include <linux/fb.h>
-#include <linux/kd.h>
-#include <stdarg.h>
-#include <string.h>
-#include <stdint.h>
-#include <stdio.h>
-#include <sys/mman.h>
-#include <sys/ioctl.h>
-#include <sys/uio.h>
-#include <time.h>
-#include <unistd.h>
-
-static const char* tmp_fmt(const char* fmt, ...)
-{
- static char msg[1024] = { 0 };
- va_list va; va_start(va, fmt);
- vsnprintf(msg, sizeof(msg), fmt, va);
- va_end(va);
- return msg;
-}
-
-static void spew(const char* message)
-{
- // Kernel log is available after init
- int kmfd = open("/dev/kmsg", O_WRONLY | O_CLOEXEC);
-
- struct iovec msgvec[] = {
-#define STRVEC(str) { .iov_base = (void*)(str), .iov_len = __builtin_strlen(str) }
- STRVEC("rlwsd: "),
- STRVEC(message),
- STRVEC("\n")
-#undef STRVEC
- };
- writev(kmfd, msgvec, sizeof(msgvec) / sizeof(*msgvec));
-
- close(kmfd);
-}
-
-static void panic(const char* message)
-{
- spew(message);
- _exit(1); // Triggers a kernel panic since we're PID 1
-}
-
-static inline uint32_t pack_rgb(const struct fb_var_screeninfo* v, uint8_t r, uint8_t g, uint8_t b)
-{
- uint32_t rv = (v->red.length ? ((uint32_t)r * ((1u << v->red.length) - 1) + 127) / 255 : 0);
- uint32_t gv = (v->green.length ? ((uint32_t)g * ((1u << v->green.length) - 1) + 127) / 255 : 0);
- uint32_t bv = (v->blue.length ? ((uint32_t)b * ((1u << v->blue.length) - 1) + 127) / 255 : 0);
- return (rv << v->red.offset) | (gv << v->green.offset) | (bv << v->blue.offset);
-}
-
-static inline void write_pixel(uint8_t* p, uint32_t bpp, uint32_t pix)
-{
- uint32_t bytes = bpp / 8;
- for (uint32_t i = 0; i < bytes; i++) {
- p[i] = (uint8_t)(pix >> (8u * i));
- }
-}
-
-int main(void)
-{
- int fd = open("/dev/fb0", O_RDWR | O_CLOEXEC);
- if (fd < 0) {
- panic(tmp_fmt("Failed to open /dev/fb0: %s", strerror(errno)));
- }
-
- struct fb_fix_screeninfo finfo;
- struct fb_var_screeninfo vinfo;
- if (ioctl(fd, FBIOGET_FSCREENINFO, &finfo) != 0) {
- panic(tmp_fmt("FBIOGET_FSCREENINFO: %s", strerror(errno)));
- }
- if (ioctl(fd, FBIOGET_VSCREENINFO, &vinfo) != 0) {
- panic(tmp_fmt("FBIOGET_VSCREENINFO: %s", strerror(errno)));
- }
-
- spew(tmp_fmt("fb0: %ux%u bpp=%u line_length=%u visual=%u",
- vinfo.xres, vinfo.yres, vinfo.bits_per_pixel,
- finfo.line_length, finfo.visual));
- spew(tmp_fmt("fb0: R %u/%u G %u/%u B %u/%u",
- vinfo.red.offset, vinfo.red.length,
- vinfo.green.offset, vinfo.green.length,
- vinfo.blue.offset, vinfo.blue.length));
-
- if (!(vinfo.bits_per_pixel == 24 || vinfo.bits_per_pixel == 32)) {
- panic("Unsupported BPP");
- }
-
- // Disable TTY
- int tty = open("/dev/tty0", O_RDWR);
- if (tty < 0) {
- tty = open("/dev/console", O_RDWR);
- if (tty < 0) {
- panic(tmp_fmt("Couldn't open tty: %s", strerror(errno)));
- }
- }
- if (ioctl(tty, KDSETMODE, KD_GRAPHICS) != 0) {
- panic(tmp_fmt("Failed to set tty mode to KD_GRAPHICS: %s", strerror(errno)));
- }
- close(tty);
-
- size_t fb_size = (size_t)finfo.line_length * vinfo.yres;
- uint8_t* fb = (uint8_t*)mmap(NULL, fb_size, PROT_READ | PROT_WRITE, MAP_SHARED, fd, 0);
- if (fb == MAP_FAILED) {
- panic(tmp_fmt("mmap failed: %s", strerror(errno)));
- }
-
- for (uint32_t y = 0; y < vinfo.yres; ++y) {
- uint8_t* row = fb + (size_t)y * finfo.line_length;
- for (size_t x = 0; x < vinfo.xres; ++x) {
- uint8_t r = 0xFF * x / vinfo.xres;
- uint8_t g = 0xFF * y / vinfo.yres;
- uint32_t color = pack_rgb(&vinfo, r, g, 0x00);
- size_t bpp = vinfo.bits_per_pixel;
- size_t bypp = bpp / 8;
- write_pixel(&row[(size_t)x * bypp], bpp, color);
- }
- }
-
- while (true) {
- pause();
- }
-}