/****************************************************************************** ReadCS() This function reads a command string from the terminal. It returns to it's caller when the command buffer pointed to by CBfBeg contains a command string. In addition to echoing the characters typed by the user, this function handles the following special things: 1. DEL (delete last character) 2. ^G* (retype command string) 3. ^G (retype command line) 4. ^G^G (delete command string) 5. ^U (delete command line) 6. ^Z^Z^Z (exit TECO-C) 7. LF (immediate mode: do a 1L1T command) 8. BS (immediate mode: do a -1L1T) 9. *q (immediate mode: store last command string in q) 10. HELP (immediate mode: access HELP subsystem) 11. / (immediate mode: display explanation of last error) 12. ? (immediate mode: display erroneous command string) *****************************************************************************/ #include "ZPort.h" /* define portability identifiers */ #include "DefTeco.h" /* define general identifiers */ #include "DefChars.h" /* define identifiers for characters */ #include "ChrMacs.h" /* define character processing macros */ #include "DefError.h" /* define identifiers for error messages */ #include "DefScren.h" /* define identifiers for screen i/o */ #define PRV_CTG '\1' /* previous character was control-G */ #define PRV_DEF '\2' /* previous character wasn't ^Z, ^G or ESC */ #define PRV_ESC '\3' /* previous character was escape */ #define PRV_Z1 '\4' /* previous character was one control-Z */ #define PRV_Z2 '\5' /* previous character was two control-Z */ extern BOOLEAN ChkHlp(); /* check for a HELP command */ extern char FrstCh(); /* input 1st command string character */ extern VOID InpDel(); /* handle a delete character */ extern LONG Ln2Chr(); /* convert line offset to character offset */ extern VOID ScrnOp(); /* do a screen operation */ extern VOID TypBuf(); /* type a buffer */ extern VOID ZAbort(); /* cleanup and exit TECO-C */ extern char ZChIn(); /* input a character from the terminal */ extern VOID ZDspBf(); /* output a buffer to the terminal */ extern VOID ZDspCh(); /* output a character to the terminal */ EXTERN char *CBfBeg; /* beginning of command buffer */ EXTERN char *CBfEnd; /* end of command buffer */ EXTERN char *CBfPtr; /* pointer into command buffer */ EXTERN LONG CRCnt; /* count of CRETRNs in command string */ EXTERN char *CStEnd; /* pointer to last char of command string */ EXTERN WORD EtFlag; /* ET mode control flag */ EXTERN WORD EvFlag; /* EV mode control flag */ EXTERN char *GapBeg; /* beginning of edit buffer gap */ EXTERN char *GapEnd; /* end of edit buffer gap */ EXTERN BOOLEAN GotCtC; /* YES if user just hit a CTRL_C */ EXTERN WORD LstErr; /* number of last error message */ VOID ReadCS() { LOCAL BOOLEAN BadSeq; /* bad escape sequence indicator */ static char ctrstr[3] = "^x"; LOCAL LONG HowFar; static char *Prompt = "\012\015*"; LOCAL BYTE PrvChr; /* previous character flags */ LOCAL char TmpChr; /* temporary character */ LOCAL char *TmpPtr; /* temporary pointer */ CRCnt = 0L; /* count of carriage-returns is 0 */ PrvChr = PRV_DEF; /* no previous characters */ CBfPtr = CBfBeg; /* command buffer is empty */ *CBfPtr = FrstCh(); /* handle 1st char until not *, / or ? */ LstErr = ERR_XXX; /* last error message is undefined */ FOREVER { if (GotCtC) /* if got a control-C */ { GotCtC = NO; ctrstr[1] = 'C'; ZDspBf(ctrstr, 2); /* display "^C" */ CBfPtr = CBfBeg - 1L; ZDspBf(Prompt, 3); /* prompt */ CRCnt = 0L; /* carriage-return count = 0 */ PrvChr = PRV_DEF; } else if (*CBfPtr == ESCAPE) if (EtFlag & ET_VT200) /* if special vt200 mode */ { *CBfPtr = ZChIn(); /* get a character */ BadSeq = NO; /* initialize BadSeq */ if (*CBfPtr != '[') BadSeq = YES; else { *CBfPtr = ZChIn(); switch (*CBfPtr) { case '2': /* f9 - f16 */ *CBfPtr = ZChIn(); if (*CBfPtr == '4') { TmpChr = ZChIn(); if (TmpChr != '~') BadSeq = YES; else *CBfPtr = BAKSPC; } else if (*CBfPtr == '5') { TmpChr = ZChIn(); if (TmpChr != '~') BadSeq = YES; else *CBfPtr = LINEFD; } else BadSeq = YES; break; #if NO case 'A': /* up arrow */ case 'B': /* down arrow */ case 'C': /* right arrow */ case 'D': /* left arrow */ #endif default: BadSeq = YES; } } if (BadSeq) { ZDspBf("\015\012\012\tInvalid escape sequence.\015\012\012", 31); ZDspBf("\tThe 16384 bit of the ET flag is set, which means\015\012", 52); ZDspBf("\tthat you are in VT200 mode. In this mode, the\015\012", 50); ZDspBf("\tescape character is not used to terminate commands.\015\012", 54); ZDspBf("\tIt is used to introduce escape sequences. This\015\012", 50); ZDspBf("\tallows the function keys to take on meanings. The\015\012", 53); ZDspBf("\taccent grave (~) character is the command terminator.\015\012", 56); ZDspBf("\tIf you want to turn off VT200 mode, say 16384,0ET``\015\012", 55); ZDspBf("\tNote that the recognition of accent grave as a\015\012", 49); ZDspBf("\tcommand terminator is controlled by the 8192 bit\015\012", 51); ZDspBf("\tof the ET flag, seperate from the VT200 bit.\015\012\012", 49); ZDspBf("\tThere may be a part of the unrecognized escape\015\012", 49); ZDspBf("\tsequence in the command string. The last line of\015\012", 52); ZDspBf("\tthe command string is shown to help you recover.\015\012", 51); PrvChr = PRV_CTG; CBfPtr++; *CBfPtr = ' '; } } else /* else not vt200 mode */ { ZDspCh('$'); if (PrvChr == PRV_ESC) { ZDspBf("\015\012", 2); CStEnd = CBfPtr; return; } PrvChr = PRV_ESC; } switch (ChrMsk[*CBfPtr] & '\17') { /* use bottom 4 bits */ case RCS_LWR: if ((EtFlag & ET_READ_LOWER) == 0) *CBfPtr &= '\137'; /* convert to upper */ case RCS_DEF: ZDspCh(*CBfPtr); PrvChr = PRV_DEF; break; case RCS_GRV: ZDspCh('`'); if (EtFlag & ET_ACCENT_GRAVE) { *CBfPtr = ESCAPE; if (PrvChr == PRV_ESC) { ZDspBf("\015\012", 2); CStEnd = CBfPtr; return; } PrvChr = PRV_ESC; } else PrvChr = PRV_DEF; break; case RCS_SP: if (PrvChr == PRV_CTG) { CBfPtr--; /* remove space */ TmpPtr = CBfPtr; while (TmpPtr > CBfBeg) { TmpPtr--; if (IsEOL(*TmpPtr)) { ++TmpPtr; break; } } ZDspBf("\015\012", 2); if (TmpPtr == CBfBeg) ZDspCh('*'); TypBuf(TmpPtr, CBfPtr); CBfPtr--; /* remove ^G */ } else ZDspCh(SPACE); PrvChr = PRV_DEF; break; case RCS_DEL: InpDel(); PrvChr = PRV_DEF; break; case RCS_CR: ZDspCh(CRETRN); if ((CRCnt == 0L) && ChkHlp(CBfPtr)) { ZDspCh('*'); CBfPtr = CBfBeg - 1L; } else ++CRCnt; PrvChr = PRV_DEF; break; case RCS_LF: if (CBfPtr == CBfBeg) /* if immediate mode */ { if (EtFlag & ET_SCOPE) { ZDspCh(CRETRN); ScrnOp(SCR_EEL); } HowFar = Ln2Chr(1L); ZCpyBl(HowFar, GapEnd+1L, GapBeg); GapBeg += HowFar; GapEnd += HowFar; if (EvFlag == 0) TypBuf(GapEnd+1L,GapEnd+Ln2Chr(1L)+1L); ZDspCh('*'); CBfPtr = CBfBeg - 1L; } else ZDspCh(LINEFD); PrvChr = PRV_DEF; break; case RCS_BS: if (CBfPtr == CBfBeg) /* if immediate mode */ { if (EtFlag & ET_SCOPE) { ZDspCh(CRETRN); ScrnOp(SCR_EEL); } HowFar = Ln2Chr(-1L); GapBeg += HowFar; GapEnd += HowFar; ZCpyBl(-HowFar, GapBeg, GapEnd+1L); if (EvFlag == 0) TypBuf(GapEnd+1L,GapEnd+Ln2Chr(1L)+1L); ZDspCh('*'); CBfPtr = CBfBeg - 1L; } else ZDspCh(BAKSPC); PrvChr = PRV_DEF; break; case RCS_CTG: ZDspBf("\7^G", 3); if (PrvChr == PRV_CTG) /* ^G^G? */ { CBfPtr = CBfBeg - 1L; ZDspBf(Prompt, 3); CRCnt = 0L; PrvChr = PRV_DEF; } else PrvChr = PRV_CTG; break; case RCS_AST: ZDspCh('*'); if (PrvChr == PRV_CTG) { CBfPtr -= 2; ZDspBf(Prompt, 3); CRCnt = 0L; TypBuf(CBfBeg, CBfPtr); } PrvChr = PRV_DEF; break; case RCS_CTZ: ctrstr[1] = 'Z'; ZDspBf(ctrstr, 2); if (PrvChr == PRV_Z2) ZAbort(); else if (PrvChr == PRV_Z1) PrvChr = PRV_Z2; else PrvChr = PRV_Z1; break; case RCS_CCH: ctrstr[1] = *CBfPtr | '\100'; ZDspBf(ctrstr, 2); PrvChr = PRV_DEF; break; case RCS_CTU: while (--CBfPtr >= CBfBeg) if (IsEOL(*CBfPtr)) break; ZDspCh(CRETRN); if (EtFlag & ET_SCOPE) ScrnOp(SCR_EEL); /* erase line */ else ZDspCh(LINEFD); if (CBfPtr CBfEnd) { /* ??? */ ZDspBf("command buffer overflow\015\012", 25); ZAbort(); /* exit TECO-C */ } *CBfPtr = ZChIn(); /* read a character */ } /* end of FOREVER loop */ } /* end of ReadCS function */