1 files changed, 161 insertions, 0 deletions
diff --git a/contrib/less/ttyin.c b/contrib/less/ttyin.c
new file mode 100644
index 0000000000000..ef87e2586cd86
--- /dev/null
+++ b/contrib/less/ttyin.c
@@ -0,0 +1,161 @@
+/*
+ * Copyright (C) 1984-2000  Mark Nudelman
+ *
+ * You may distribute under the terms of either the GNU General Public
+ * License or the Less License, as specified in the README file.
+ *
+ * For more information about less, or for information on how to 
+ * contact the author, see the README file.
+ */
+
+
+/*
+ * Routines dealing with getting input from the keyboard (i.e. from the user).
+ */
+
+#include "less.h"
+#if MSDOS_COMPILER==WIN32C
+#include "windows.h"
+extern char WIN32getch();
+static DWORD console_mode;
+#endif
+
+static int tty;
+extern int sigs;
+
+/*
+ * Open keyboard for input.
+ */
+	public void
+open_getchr()
+{
+#if MSDOS_COMPILER==WIN32C
+	/* Need this to let child processes inherit our console handle */
+	SECURITY_ATTRIBUTES sa;
+	memset(&sa, 0, sizeof(SECURITY_ATTRIBUTES));
+	sa.nLength = sizeof(SECURITY_ATTRIBUTES);
+	sa.bInheritHandle = TRUE;
+	tty = (int) CreateFile("CONIN$", GENERIC_READ,
+			FILE_SHARE_READ, &sa, 
+			OPEN_EXISTING, 0L, NULL);
+	GetConsoleMode((HANDLE)tty, &console_mode);
+	/* Make sure we get Ctrl+C events. */
+	SetConsoleMode((HANDLE)tty, ENABLE_PROCESSED_INPUT);
+#else
+#if MSDOS_COMPILER || OS2
+	extern int fd0;
+	/*
+	 * Open a new handle to CON: in binary mode 
+	 * for unbuffered keyboard read.
+	 */
+	 fd0 = dup(0);
+	 close(0);
+	 tty = open("CON", OPEN_READ);
+#if MSDOS_COMPILER==DJGPPC
+	/*
+	 * Setting stdin to binary causes Ctrl-C to not
+	 * raise SIGINT.  We must undo that side-effect.
+	 */
+	(void) __djgpp_set_ctrl_c(1);
+#endif
+#else
+	/*
+	 * Try /dev/tty.
+	 * If that doesn't work, use file descriptor 2,
+	 * which in Unix is usually attached to the screen,
+	 * but also usually lets you read from the keyboard.
+	 */
+	tty = open("/dev/tty", OPEN_READ);
+	if (tty < 0)
+		tty = 2;
+#endif
+#endif
+}
+
+/*
+ * Close the keyboard.
+ */
+	public void
+close_getchr()
+{
+#if MSDOS_COMPILER==WIN32C
+	SetConsoleMode((HANDLE)tty, console_mode);
+	CloseHandle((HANDLE)tty);
+#endif
+}
+
+/*
+ * Get a character from the keyboard.
+ */
+	public int
+getchr()
+{
+	char c;
+	int result;
+
+	do
+	{
+#if MSDOS_COMPILER && MSDOS_COMPILER != DJGPPC
+		/*
+		 * In raw read, we don't see ^C so look here for it.
+		 */
+		flush();
+#if MSDOS_COMPILER==WIN32C
+		if (ABORT_SIGS())
+			return (READ_INTR);
+		c = WIN32getch(tty);
+#else
+		c = getch();
+#endif
+		result = 1;
+		if (c == '\003')
+			return (READ_INTR);
+#else
+#if OS2
+	{
+		static int scan = -1;
+		flush();
+		if (scan >= 0)
+		{
+			c = scan;
+			scan = -1;
+		} else
+		{
+			if ((c = _read_kbd(0, 1, 0)) == -1)
+				return (READ_INTR);
+			if (c == '\0')
+			{
+				/*
+				 * Zero is usually followed by another byte,
+				 * since certain keys send two bytes.
+				 */
+				scan = _read_kbd(0, 0, 0);
+			}
+		}
+		result = 1;
+	}
+#else
+		result = iread(tty, &c, sizeof(char));
+		if (result == READ_INTR)
+			return (READ_INTR);
+		if (result < 0)
+		{
+			/*
+			 * Don't call error() here,
+			 * because error calls getchr!
+			 */
+			quit(QUIT_ERROR);
+		}
+#endif
+#endif
+		/*
+		 * Various parts of the program cannot handle
+		 * an input character of '\0'.
+		 * If a '\0' was actually typed, convert it to '\340' here.
+		 */
+		if (c == '\0')
+			c = '\340';
+	} while (result != 1);
+
+	return (c & 0377);
+}