4 files changed, 81 insertions, 0 deletions
diff --git a/os/main.c b/os/main.c
new file mode 100644
index 0000000..905b0f7
--- /dev/null
+++ b/os/main.c
@@ -0,0 +1,42 @@
+#include "../kernel/gpu/text_mode/display.h"
+#include "../kernel/gpu/text_mode/colours.h"
+#include "main.h"
+#include "./shell/shell.h"
+
+Program_t focused_program;
+
+void os_show_splash()
+{
+  scrn_enable_cursor(10, 12);
+  scrn_clear();
+  scrn_set_text_colour(COLOUR_LIGHT_GREEN, COLOUR_BLACK);
+
+  scrn_println("  _   _              ____   _____ ");
+  scrn_println(" | | (_)            / __ \\ / ____|");
+  scrn_println(" | |_ _ _ __  _   _| |  | | (___  ");
+  scrn_println(" | __| | '_ \\| | | | |  | |\\___ \\ ");
+  scrn_println(" | |_| | | | | |_| | |__| |____) |");
+  scrn_println("  \\__|_|_| |_|\\__, |\\____/|_____/ ");
+  scrn_println("               __/ |              ");
+  scrn_println("              |___/               ");
+
+  scrn_set_text_colour(COLOUR_WHITE, COLOUR_BLACK);
+  scrn_newline();
+}
+
+void os_start()
+{
+  os_show_splash();
+}
+
+// TODO keep a stack of running programs
+void os_update_focused_program(Program_t program) {
+  focused_program = shell_run();
+}
+
+// Send keypress from kernel to the currently focused programs keypress handler
+void os_proxy_keypress(unsigned char key) {
+  (focused_program.keypress_handler)(key);
+}
+
+// TODO display handling
+\ No newline at end of file
diff --git a/os/main.h b/os/main.h
new file mode 100644
index 0000000..a632750
--- /dev/null
+++ b/os/main.h
@@ -0,0 +1,13 @@
+#ifndef MAIN_H
+#define MAIN_H
+
+typedef struct
+{
+  char *name;
+  void (*keypress_handler)(unsigned char);
+} Program_t;
+
+void os_start();
+void os_proxy_keypress(unsigned char key);
+
+#endif
+\ No newline at end of file
diff --git a/os/shell/shell.c b/os/shell/shell.c
new file mode 100644
index 0000000..933b19c
--- /dev/null
+++ b/os/shell/shell.c
@@ -0,0 +1,23 @@
+#include "../../os/main.h"
+#include "../../kernel/gpu/text_mode/display.h"
+
+void keypress_handler(unsigned char key) {
+  switch(key)
+    {
+      case '\b':
+        scrn_backspace();
+        break;
+      case '\n':
+        scrn_newline();
+        break;
+      default:
+        scrn_putchar(key);
+    }
+}
+
+Program_t shell_run() {
+  Program_t this;
+  this.keypress_handler = keypress_handler;
+  this.name = "shell";
+  return this;
+}
+\ No newline at end of file
diff --git a/os/shell/shell.h b/os/shell/shell.h
new file mode 100644
index 0000000..2a8f508
--- /dev/null
+++ b/os/shell/shell.h
@@ -0,0 +1,3 @@
+#include "../../os/main.h"
+
+Program_t shell_run();
+\ No newline at end of file