splitting things out

terminal.c

@@ -0,0 +1,70 @@
+#include <stdlib.h>
+#include <termios.h>
+#include <unistd.h>
+
+#include "util.h"
+
+
+static struct termios	entry_term;
+
+
+/*
+ * A text editor needs the terminal to be in raw mode; but the default
+ * is to be in canonical (cooked) mode, which is a buffered input mode.
+ */
+
+static void
+enable_termraw()
+{
+	struct termios	raw;
+
+	/* Read the current terminal parameters for standard input. */
+	if (tcgetattr(STDIN_FILENO, &raw) == -1) {
+		die("tcgetattr while enabling raw mode");
+	}
+
+	/*
+	 * Put the terminal into raw mode.
+	 */
+	cfmakeraw(&raw);
+
+	/*
+	 * Set timeout for read(2).
+	 *
+	 * VMIN: what is the minimum number of bytes required for read
+	 * to return?
+	 *
+	 * VTIME: max time before read(2) returns in hundreds of milli-
+	 * seconds.
+	 */
+	raw.c_cc[VMIN] = 0;
+	raw.c_cc[VTIME] = 1;
+
+	/*
+	 * Now write the terminal parameters to the current terminal,
+	 * after flushing any waiting input out.
+	 */
+	if (tcsetattr(STDIN_FILENO, TCSAFLUSH, &raw) == -1) {
+		die("tcsetattr while enabling raw mode");
+	}
+}
+
+
+static void
+disable_termraw()
+{
+	if (tcsetattr(STDIN_FILENO, TCSAFLUSH, &entry_term) == -1) {
+		die("couldn't disable terminal raw mode");
+	}
+}
+
+
+void
+setup_terminal()
+{
+	if (tcgetattr(STDIN_FILENO, &entry_term) == -1) {
+		die("can't snapshot terminal settings");
+	}
+	atexit(disable_termraw);
+	enable_termraw();
+}