diff options
| author | Hunter Kvalevog <hunter@kvog.sh> | 2026-02-15 18:48:59 -0600 |
|---|---|---|
| committer | Hunter Kvalevog <hunter@kvog.sh> | 2026-02-15 18:48:59 -0600 |
| commit | 7d7f38fed94e50c0a8427cb814cb996a472219a2 (patch) | |
| tree | 4b06d8d1dbde8c9b0f34fba0acb63a484ea7bd5d /rushmore-linux/rlws | |
| parent | 0f6104b8a5d50c87c8f3f1ab4ec62e0dd1bf3704 (diff) | |
rlws -> rltest
Diffstat (limited to 'rushmore-linux/rlws')
| -rw-r--r-- | rushmore-linux/rlws/rlws.c | 125 |
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(); - } -} |