Mouse (src/mouse.c)

Functions and behavior:

• inb(port), outb(port, val) — Low-level port I/O helpers used by the mouse code.
• mouse_wait_input() / mouse_wait_output() — Wait for PS/2 controller readiness (timeout-protected to avoid hangs).
• mouse_write(data), mouse_read() — Send/read bytes to/from the PS/2 mouse (returns 0 on timeout).
• init_mouse() — Initialize the PS/2 mouse, enable data reporting, and centre the cursor on screen.
• mouse_handler() — Interrupt handler that assembles 3-byte packets, updates mouse state, and clamps position to screen bounds.
• get_mouse_state() — Return pointer to global mouse_state_t.

Source: src/mouse.c