make_ctrl_char (c)
int c;
{
- /* If it's already a control character, don't mess with it. */
- if ((c & 0160) == 0)
- ;
- /* Making ? a control character should result in DEL. */
-
- else if ((c & 0177) == '?')
- c |= 0177;
-
- /* ASCII control chars are made from letters (both cases),
- as well as the non-letters within 0100...0137. */
- else if ((c & 0137) >= 'A' && (c & 0137) <= 'Z')
- c = (c & (037 | ~0177));
- else if ((c & 0177) >= 0100 && (c & 0177) <= 0137)
- c = (c & (037 | ~0177));
-
- /* Anything else must get its high control bit set. */
- else
- c = c | ctrl_modifier;
+ /* Save the upper bits here. */
+ int upper = c & ~0177;
+
+ c &= 0177;
+
+ /* Everything in the columns containing the upper-case letters
+ denotes a control character. */
+ if (c >= 0100 && c < 0140)
+ {
+ int oc = c;
+ c &= ~0140;
+ /* Set the shift modifier for a control char
+ made from a shifted letter. But only for letters! */
+ if (oc >= 'A' && oc <= 'Z')
+ c |= shift_modifier;
+ }
+
+ /* The lower-case letters denote control characters too. */
+ else if (c >= 'a' && c <= 'z')
+ c &= ~0140;
+
+ /* Include the bits for control and shift
+ only if the basic ASCII code can't indicate them. */
+ else if (c >= ' ')
+ c |= ctrl_modifier;
+
+ /* Replace the high bits. */
+ c |= (upper & ~ctrl_modifier);
return c;
}
/* Turn ASCII characters into control characters
when proper. */
if (event->modifiers & ctrl_modifier)
- {
- if (c >= 0100 && c < 0140)
- {
- int oc = c;
- c &= ~0140;
- /* Set the shift modifier for a control char
- made from a shifted letter. But only for letters! */
- if (oc >= 'A' && oc <= 'Z')
- c |= shift_modifier;
- }
- else if (c >= 'a' && c <= 'z')
- c &= ~0140;
- /* Include the bits for control and shift
- only if the basic ASCII code can't indicate them. */
- else
- c |= ctrl_modifier;
- }
+ c = make_ctrl_char (c);
+
+ /* Add in the other modifier bits. We took care of ctrl_modifier
+ just above, and the shift key was taken care of by the X code,
+ and applied to control characters by make_ctrl_char. */
c |= (event->modifiers
& (meta_modifier | alt_modifier
| hyper_modifier | super_modifier));