InterfaceDefs: complete ASCII control char definitions

Make it clear that this enum just defines ASCII control characters, and
there is no 'free space'. Also add comment showing which key combination
produces each control character.

Change-Id: I01884132842281cce6c13dd9398b1aeddadae58a
Reviewed-on: https://review.haiku-os.org/c/haiku/+/8899
Reviewed-by: nephele nephele <[email protected]>
Tested-by: Commit checker robot <[email protected]>
Reviewed-by: waddlesplash <[email protected]>

headers/os/interface/InterfaceDefs.h

@@ -40,22 +40,36 @@ struct key_info {
 	uint8	key_states[16];
 };
 
+// Control characters from the ASCII table
 enum {
-	B_HOME				= 0x01,
-
-	B_END				= 0x04,
-	B_INSERT			= 0x05,
-
-	B_BACKSPACE			= 0x08,
-	B_TAB				= 0x09,
-	B_RETURN			= 0x0a,
+	B_ASCII_NUL,
+	B_HOME				= 0x01,	// Ctrl + A
+	B_ASCII_START_TEXT,			// Ctrl + B
+	B_ASCII_END_TEXT,			// Ctrl + C
+	B_END				= 0x04,	// Ctrl + D
+	B_INSERT			= 0x05,	// Ctrl + E
+	B_ASCII_ACKNOWLEDGE, 		// Ctrl + F
+	B_ASCII_BELL, 				// Ctrl + G
+	B_BACKSPACE			= 0x08,	// Ctrl + H
+	B_TAB				= 0x09,	// Ctrl + I
+	B_RETURN			= 0x0a,	// Ctrl + J
 	B_ENTER				= 0x0a,
-	B_PAGE_UP			= 0x0b,
-	B_PAGE_DOWN			= 0x0c,
-
-	B_FUNCTION_KEY		= 0x10,
-
-	B_SUBSTITUTE		= 0x1a,
+	B_PAGE_UP			= 0x0b,	// Ctrl + K
+	B_PAGE_DOWN			= 0x0c,	// Ctrl + L
+	B_ASCII_CARRIAGE_RETURN,	// Ctrl + M
+	B_ASCII_SHIFT_OUT,			// Ctrl + N
+	B_ASCII_SHIFT_IN,			// Ctrl + O
+	B_FUNCTION_KEY		= 0x10, // Ctrl + P
+	B_ASCII_XON,				// Ctrl + Q
+	B_DEVICE_CONTROL_2,			// Ctrl + R
+	B_ASCII_XOFF,				// Ctrl + S
+	B_DEVICE_CONTROL_4,			// Ctrl + T
+	B_ASCII_NEGATIVE_ACK,		// Ctrl + U
+	B_ASCII_SYNC_IDLE,			// Ctrl + V
+	B_ASCII_END_TRANSMISSION_BLOCK, // Ctrl + W
+	B_ASCII_CANCEL,				// Ctrl + X
+	B_ASCII_END_MEDIUM,			// Ctrl + Y
+	B_SUBSTITUTE		= 0x1a, // Ctrl + Z
 	B_ESCAPE			= 0x1b,
 	B_LEFT_ARROW		= 0x1c,
 	B_RIGHT_ARROW		= 0x1d,