Remove unused ffi prototypes, make php equivalent functions

src/Editor.php

@@ -785,7 +785,7 @@ class Editor {
 			{
 				$buffer = substr($buffer, 0, -1);
 			}
-			else if ($cord < 128 && $this->ffi->iscntrl($cord) === 0 && ! in_array($c, $modifiers, TRUE))
+			else if (isascii($c) && ( ! iscntrl($c)) && ! in_array($c, $modifiers, TRUE))
 			{
 				$buffer .= $c;
 			}

src/ffi.h

@@ -49,15 +49,6 @@ struct termios
 int tcgetattr (int fd, struct termios *termios_p);
 int tcsetattr (int fd, int optional_actions, const struct termios *termios_p);
 
-void cfmakeraw (struct termios *termios_p);
-
-// -----------------------------------------------------------------------------
-//! <ctype.h>
-// -----------------------------------------------------------------------------
-int iscntrl (int);
-
-ssize_t read(int, void *, size_t);
-
 // -----------------------------------------------------------------------------
 //! <sys/ioctl.h>
 // -----------------------------------------------------------------------------

src/functions.php

@@ -98,3 +98,25 @@ function ctrl_key(string $char): int
 	// b1,100,010 (b) & b0,011,111 = b0,000,010
 	return ord($char) & 0x1f;
 }
+
+function isascii(string $single_char): bool
+{
+	if (strlen($single_char) > 1)
+	{
+		return FALSE;
+	}
+
+	return ord($single_char) < 0x80;
+}
+
+function iscntrl(string $char): bool
+{
+	$c = ord($char);
+	return isascii($char) && ( $c < 0x20 || $c === 0x7f );
+}
+
+function isdigit(string $char): bool
+{
+	$c = ord($char);
+	return isascii($char) && ( $c > 0x2f && $c < 0x3a );
+}