Some syscalls and userspace stuff

sorry for the worse-getting commit messages...

1 files changed, 35 insertions, 4 deletions

diff --git a/src/userspace/main.c b/src/userspace/main.c
index 64077eb..4e036c5 100644
--- a/src/userspace/main.c
+++ b/src/userspace/main.c
@@ -1,12 +1,43 @@
 #include <syscall.h>
 
+char *fb;
+int vbe_bpl = 3;
+int vbe_pitch = 3000;
+int vbe_height = 1080;
+int vbe_width = 2560;
+
+void vesa_draw_rectangle(int x1, int y1, int x2, int y2, const uint32_t color[3])
+{
+    int pos1 = x1 * vbe_bpl + y1 * vbe_pitch;
+    char *draw = (char *) &fb[pos1];
+    for (int i = 0; i <= y2 - y1; i++) {
+        for (int j = 0; j <= x2 - x1; j++) {
+            draw[vbe_bpl * j] = color[2];
+            draw[vbe_bpl * j + 1] = color[1];
+            draw[vbe_bpl * j + 2] = color[0];
+        }
+        draw += vbe_pitch;
+    }
+}
+
+void vesa_clear()
+{
+    vesa_draw_rectangle(0, 0, vbe_width - 1, vbe_height - 1, 0);
+}
+
 void user_main()
 {
     char hello[] = "> Successfully switched to usermode!\n";
     syscall_write(hello);
 
-    while (1) {
-        char ch = (char) syscall_readc();
-        syscall_writec(ch);
-    };
+    // fb = (char *) 0x110048;
+    // vesa_clear();
+
+    while (1) {};
+
+    /*while (1) {
+        char *key = malloc(1);
+        syscall_readc(key);
+        syscall_writec(key);
+    };*/
 }
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