Add missing utils module

utils.nim

@@ -0,0 +1,65 @@
+when defined(windows):
+  import winlean
+  type
+    SHORT = int16
+    COORD = object
+      X: SHORT
+      Y: SHORT
+
+    SMALL_RECT = object
+      Left: SHORT
+      Top: SHORT
+      Right: SHORT
+      Bottom: SHORT
+
+    CONSOLE_SCREEN_BUFFER_INFO = object
+      dwSize: COORD
+      dwCursorPosition: COORD
+      wAttributes: int16
+      srWindow: SMALL_RECT
+      dwMaximumWindowSize: COORD
+
+  proc getConsoleScreenBufferInfo(hConsoleOutput: HANDLE,
+    lpConsoleScreenBufferInfo: ptr CONSOLE_SCREEN_BUFFER_INFO): WINBOOL{.stdcall,
+    dynlib: "kernel32", importc: "GetConsoleScreenBufferInfo".}
+
+  proc getTermSize*(): (int, int) =
+    let handle = getStdHandle(STD_OUTPUT_HANDLE)
+    var scrbuf: CONSOLE_SCREEN_BUFFER_INFO
+    let ret = getConsoleScreenBufferInfo(handle, addr(scrbuf))
+
+    if ret == -1:
+      return (-1, -1)
+
+    let cols = scrbuf.srWindow.Right - scrbuf.srWindow.Left + 1
+    let rows = scrbuf.srWindow.Bottom - scrbuf.srWindow.Top + 1
+
+    return (rows.int, cols.int)
+
+else:
+  import posix
+  type
+    winsize = object
+      ws_row: cushort
+      ws_col: cushort
+      ws_xpixel: cushort
+      ws_ypixel: cushort
+
+  let
+    IOC_OUT = 0x40000000
+    IOCPARM_MASK = 0x1fff
+
+  var
+    TIOCGWINSZ{.importc: "TIOCGWINSZ", header: "<sys/ioctl.h>".}: uint
+
+  proc ioctl*(f: int, device: uint, w: var winsize): int {.importc: "ioctl",
+      header: "<sys/ioctl.h>", varargs, tags: [WriteIOEffect].}
+
+  proc getTermSize*(): (int, int) =
+    var w: winsize
+    let ret = ioctl(STDOUT_FILENO, TIOCGWINSZ, addr(w))
+
+    if ret == -1:
+      return (-1, -1)
+
+    return (w.ws_row.int, w.ws_col.int)