Support PETSCII terminals connected to non-PETSCII ports

The reported problem (by John "Jay" Crutti) was:
If autodetection of the terminal is used from the defaults menu I get stuck on the prompt to hit my Delete key because on the BBS, it keeps showing me login statistics every time I hit my delete key. 

Add/use new K_CTRLKEYS mode to stop inkey() from handling/eating control-keys (e.g. Ctrl-T) when asking user to hit backspace during defaults->terminal settings.

Allow PETSCII_DELETE (Ctrl-T) as a valid option when asking for the backspace/delete key and set the PETSCII flag in the autoterm variable if hit by the user.

src/sbbs3/inkey.cpp

@@ -116,7 +116,7 @@ char sbbs_t::inkey(long mode, unsigned long timeout)
 	this->timeout=time(NULL);
 
 	/* Is this a control key */
-	if(ch<' ') {
+	if(!(mode & K_CTRLKEYS) && ch < ' ') {
 		if(cfg.ctrlkey_passthru&(1<<ch))	/*  flagged as passthru? */
 			return(ch);						/* do not handle here */
 		return(handle_ctrlkey(ch,mode));

src/sbbs3/newuser.cpp

@@ -154,7 +154,7 @@ BOOL sbbs_t::newuser()
 
 		while(text[HitYourBackspaceKey][0] && !(useron.misc&(PETSCII|SWAP_DELETE)) && online) {
 			bputs(text[HitYourBackspaceKey]);
-			uchar key = getkey(K_NONE);
+			uchar key = getkey(K_CTRLKEYS);
 			bprintf(text[CharacterReceivedFmt], key, key);
 			if(key == '\b')
 				break;

src/sbbs3/sbbsdefs.h

@@ -767,6 +767,7 @@ typedef enum {						/* Values for xtrn_t.event				*/
 #define K_NOSPIN	(1L<<21)	/* Do not honor the user's spinning cursor	*/
 #define K_ANSI_CPR	(1L<<22)	/* Expect ANSI Cursor Position Report		*/
 #define K_TRIM		(1L<<23)	/* Trimmed white-space						*/
+#define K_CTRLKEYS	(1L<<24)	/* No control-key handling/eating in inkey()*/
 
 								/* Bits in 'mode' for putmsg and printfile  */
 #define P_NONE		0			/* No mode flags							*/

src/sbbs3/useredit.cpp

@@ -38,6 +38,7 @@
 /*******************************************************************/
 
 #include "sbbs.h"
+#include "petdefs.h"
 
 #define SEARCH_TXT 0
 #define SEARCH_ARS 1
@@ -974,9 +975,9 @@ void sbbs_t::maindflts(user_t* user)
 					else
 						user->misc&=~NO_EXASCII;
 					user->misc &= ~SWAP_DELETE;
-					while(text[HitYourBackspaceKey][0] && !(user->misc&SWAP_DELETE) && online) {
+					while(text[HitYourBackspaceKey][0] && !(user->misc&(PETSCII|SWAP_DELETE)) && online) {
 						bputs(text[HitYourBackspaceKey]);
-						uchar key = getkey(K_NONE);
+						uchar key = getkey(K_CTRLKEYS);
 						bprintf(text[CharacterReceivedFmt], key, key);
 						if(key == '\b')
 							break;
@@ -984,6 +985,12 @@ void sbbs_t::maindflts(user_t* user)
 							if(text[SwapDeleteKeyQ][0] == 0 || yesno(text[SwapDeleteKeyQ]))
 								user->misc |= SWAP_DELETE;
 						}
+						else if(key == PETSCII_DELETE) {
+							autoterm |= PETSCII;
+							user->misc |= PETSCII;
+							outcom(PETSCII_UPPERLOWER);
+							bputs(text[PetTerminalDetected]);
+						}
 						else
 							bprintf(text[InvalidBackspaceKeyFmt], key, key);
 					}