# Primitives for screen control. # Require Linux and a modern terminal. == code enable-screen-grid-mode: # . prologue 55/push-ebp 89/<- %ebp 4/r32/esp # (flush Stdout) (flush Stderr) # switch to second screen buffer (write 2 Esc) (write 2 "[?1049h") # (clear-screen) $enable-screen-grid-mode:end: # . epilogue 89/<- %esp 5/r32/ebp 5d/pop-to-ebp c3/return enable-screen-type-mode: # . prologue 55/push-ebp 89/<- %ebp 4/r32/esp # switch to first screen buffer (write 2 Esc) (write 2 "[?1049l") $enable-screen-type-mode:end: # . epilogue 89/<- %esp 5/r32/ebp 5d/pop-to-ebp c3/return screen-size: # -> nrows/eax: int, ncols/ecx: int # . prologue 55/push-ebp 89/<- %ebp 4/r32/esp # . save registers 50/push-eax 51/push-ecx 52/push-edx 53/push-edx 56/push-esi 57/push-edi # (_maybe-open-terminal) # var window-size-info/esi: (addr winsize) # winsize is a type from the Linux kernel. We don't care how large it is. 81 5/subop/subtract %esp 0x40/imm32 89/<- %esi 4/r32/esp # ioctl(*Terminal-file-descriptor, TIOCGWINSZ, window-size-info) 89/<- %edx 6/r32/esi b9/copy-to-ecx 0x5413/imm32/TIOCGWINSZ 8b/-> *Terminal-file-descriptor 3/r32/ebx e8/call syscall_ioctl/disp32 # some bitworking to extract 2 16-bit shorts 8b/-> *esi 0/r32/eax 81 4/subop/and %eax 0xffff/imm32 8b/-> *esi 1/r32/ecx c1/shift 5/subop/logical-right %ecx 0x10/imm8 $screen-size:end: # . reclaim locals 81 0/subop/add %esp 0x40/imm32 # . restore registers 5f/pop-to-edi 5e/pop-to-esi 5b/pop-to-ebx 5a/pop-to-edx 59/pop-to-ecx 58/pop-to-eax # . epilogue 89/<- %esp 5/r32/ebp 5d/pop-to-ebp c3/return clear-screen: # . prologue 55/push-ebp 89/<- %ebp 4/r32/esp # (write 2 Esc) (write 2 "[H") (write 2 Esc) (write 2 "[2J") $clear-screen:end: # . epilogue 89/<- %esp 5/r32/ebp 5d/pop-to-ebp c3/return move-cursor: # row: int, column: int # . prologue 55/push-ebp 89/<- %ebp 4/r32/esp # . save registers 51/push-ecx # var buf/ecx: (stream byte 32) 81 5/subop/subtract %esp 0x20/imm32 68/push 0x20/imm32/size 68/push 0/imm32/read 68/push 0/imm32/write 89/<- %ecx 4/r32/esp # construct directive in buf (write %ecx Esc) (write %ecx "[") (print-int32-decimal %ecx *(ebp+8)) (write %ecx ";") (print-int32-decimal %ecx *(ebp+0xc)) (write %ecx "H") # flush (write-stream 2 %ecx) $move-cursor:end: # . reclaim locals 81 0/subop/add %esp 0x2c/imm32 # . restore registers 59/pop-to-ecx # . epilogue 89/<- %esp 5/r32/ebp 5d/pop-to-ebp c3/return print-string: # s: (addr array byte) # . prologue 55/push-ebp 89/<- %ebp 4/r32/esp # (write 2 *(ebp+8)) $print-string:end: # . epilogue 89/<- %esp 5/r32/ebp 5d/pop-to-ebp c3/return print-int32-to-screen: # n: int # . prologue 55/push-ebp 89/<- %ebp 4/r32/esp # (print-int32-buffered Stdout *(ebp+8)) (flush Stdout) $print-int32-to-screen:end: # . epilogue 89/<- %esp 5/r32/ebp 5d/pop-to-ebp c3/return reset-formatting: # . prologue 55/push-ebp 89/<- %ebp 4/r32/esp # (write 2 Esc) (write 2 "(B") (write 2 Esc) (write 2 "[m") $reset-formatting:end: # . epilogue 89/<- %esp 5/r32/ebp 5d/pop-to-ebp c3/return start-color: # fg: int, bg: int # . prologue 55/push-ebp 89/<- %ebp 4/r32/esp # . save registers 51/push-ecx # var buf/ecx: (stream byte 32) 81 5/subop/subtract %esp 0x20/imm32 68/push 0x20/imm32/size 68/push 0/imm32/read 68/push 0/imm32/write 89/<- %ecx 4/r32/esp # construct directive in buf # . set fg (write %ecx Esc) (write %ecx "[38;5;") (print-int32-decimal %ecx *(ebp+8)) (write %ecx "m") # . set bg (write %ecx Esc) (write %ecx "[48;5;") (print-int32-decimal %ecx *(ebp+0xc)) (write %ecx "m") # flush (write-stream 2 %ecx) $start-color:end: # . reclaim locals 81 0/subop/add %esp 0x2c/imm32 # . restore registers 59/pop-to-ecx # . epilogue 89/<- %esp 5/r32/ebp 5d/pop-to-ebp c3/return start-bold: # . prologue 55/push-ebp 89/<- %ebp 4/r32/esp # (write 2 Esc) (write 2 "[1m") $start-bold:end: # . epilogue 89/<- %esp 5/r32/ebp 5d/pop-to-ebp c3/return start-underline: # . prologue 55/push-ebp 89/<- %ebp 4/r32/esp # (write 2 Esc) (write 2 "[4m") $start-underline:end: # . epilogue 89/<- %esp 5/r32/ebp 5d/pop-to-ebp c3/return start-reverse-video: # . prologue 55/push-ebp 89/<- %ebp 4/r32/esp # (write 2 Esc) (write 2 "[7m") $start-reverse-video:end: # . epilogue 89/<- %esp 5/r32/ebp 5d/pop-to-ebp c3/return # might require enabling blinking in your terminal program start-blinking: # . prologue 55/push-ebp 89/<- %ebp 4/r32/esp # (write 2 Esc) (write 2 "[5m") $start-blinking:end: # . epilogue 89/<- %esp 5/r32/ebp 5d/pop-to-ebp c3/return hide-cursor: # . prologue 55/push-ebp 89/<- %ebp 4/r32/esp # (write 2 Esc) (write 2 "[?25l") $hide-cursor:end: # . epilogue 89/<- %esp 5/r32/ebp 5d/pop-to-ebp c3/return show-cursor: # . prologue 55/push-ebp 89/<- %ebp 4/r32/esp # (write 2 Esc) (write 2 "[?12l") (write 2 Esc) (write 2 "[?25h") $show-cursor:end: # . epilogue 89/<- %esp 5/r32/ebp 5d/pop-to-ebp c3/return # This is a low-level detail; I don't think everything should be a file. # # Open "/dev/tty" if necessary and cache its file descriptor in Terminal-file-descriptor # where later primitives can use it. _maybe-open-terminal: 81 7/subop/compare *Terminal-file-descriptor -1/imm32 75/jump-if-!= $_maybe-open-terminal:epilogue/disp8 # . save registers 50/push-eax 51/push-ecx 53/push-ebx # open("/dev/tty", O_RDWR) bb/copy-to-ebx Terminal-filename/imm32 b9/copy-to-ecx 2/imm32/O_RDWR e8/call syscall_open/disp32 89/<- *Terminal-file-descriptor 0/r32/eax $_maybe-open-terminal:end: # . restore registers 5b/pop-to-ebx 59/pop-to-ecx 58/pop-to-eax $_maybe-open-terminal:epilogue: c3/return == data Terminal-file-descriptor: # (addr int) -1/imm32 Esc: # (addr array byte) # size 1/imm32 # data 0x1b Terminal-filename: # (addr kernel-string) # "/dev/null" 2f/slash 64/d 65/e 76/v 2f/slash 74/t 74/t 79/y 0/nul