TEACL is a fork of TECOC created for the purpose of describing diffs in a document being collaboratively edited
You can not select more than 25 topics Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
 
 

167 lines
5.0 KiB

/*****************************************************************************
ExeO()
This function executes an O command.
Otag Goto label
nOtag0,tag1 Computed goto
*****************************************************************************/
#include "zport.h" /* define portability identifiers */
#include "tecoc.h" /* define general identifiers */
#include "defext.h" /* define external global variables */
#include "dchars.h" /* define identifiers for characters */
#include "deferr.h" /* define identifiers for error messages */
DEFAULT ExeO() /* execute an O command */
{
BOOLEAN Found; /* has the tag been found? */
unsigned char TBfBeg[TBFINIT]; /* tag buffer */
charptr TBfEnd; /* end of tag buffer */
charptr TBfPtr; /* end of tag in tag buffer */
charptr TagPtr; /* pointer into tag buffer */
charptr TmpPtr; /* temp pointer for shuffling in Tbf */
DBGFEN(1,"ExeO",NULL);
/*
* ??? Pete,
* given "O^EQq$" we simply use BldStr to build the string
* before looking for the tag in q-reg q. What do we do if
* given "nOtag0,^EQq,tag2$", especially if q-reg q contains a
* comma? if we BldStr first, the comma in the q-reg will
* change the number of tags, maybe changing the nth tag.
* If we BldStr after finding the tag we want, we don't take
* into account the list of tags which may be in q-reg q.
*
* After implementing it the second way (search/Bldstr), I find
* it is much easier to do it the first way (BldStr/search). One
* disadvantage to doing it this way is BldStr is probably building
* much more than it needs to, potentially overrunning TBf?
*/
TBfEnd = TBfBeg + TBFINIT;
if (BldStr(TBfBeg, TBfEnd, &TBfPtr) == FAILURE) {
DBGFEX(1,DbgFNm,"FAILURE, BldStr() failed");
return FAILURE;
}
/*
* If there's something on the expression stack, then we have a computed
* goto, so figure out which tag in TBf they want.
*
* TBf: "TAG0,TAG1,TAG2........"
* ^ ^ ^
* TBfBeg TBfPtr TBfEnd
*/
if (EStTop > EStBot) {
if (GetNmA () == FAILURE) { /* get NArgmt */
DBGFEX(1,DbgFNm,"FAILURE, GetNmA() failed");
return FAILURE;
}
if (NArgmt < 0) { /* n is out of range */
TagPtr = TBfPtr; /* say we ran into end of tag list */
} else { /* find the nth tag */
TagPtr = TBfBeg;
if (NArgmt > 0) { /* n==0 is already done */
while (TagPtr < TBfPtr) {
if (*TagPtr++ == ',') {
if (--NArgmt == 0) {
break;
}
}
}
}
}
/*
* If we ran into the end of the tag list, or the tag we found is null
* (",,"), then flow past nO command.
*/
if (TagPtr == TBfPtr || *TagPtr == ',') {
DBGFEX(1,DbgFNm,"SUCCESS");
CmdMod = '\0'; /* clear modifiers flags */
return SUCCESS;
}
/*
* shuffle tag we found to beginning of TBf for searching.
*/
TmpPtr = TBfBeg;
while (TagPtr < TBfPtr && *TagPtr != ',') {
*TmpPtr++ = *TagPtr++;
}
TBfPtr = TmpPtr;
}
#if DEBUGGING
*TBfPtr = '\0';
sprintf(DbgSBf,"searching for tag \"%s\"", TBfBeg);
DbgFMs(1,DbgFNm,DbgSBf);
#endif
/*
* reset CBfPtr to point to the front of the command string, or the front
* of the loop if we're in a loop, then search for the tag in TBf, keeping
* track of nested <> loops.
*/
CBfPtr = (LStTop == LStBot) ? CStBeg : LStack[LStTop].LAddr + 1;
Found = FALSE;
CmdMod = '\0'; /* clear modifiers flags */
while (!Found) {
while (*CBfPtr != '!') {
if (CBfPtr == CStEnd) {
ErrPSt(ERR_TAG, TBfBeg, TBfPtr);
DBGFEX(1,DbgFNm,"FAILURE, missing tag");
return FAILURE;
}
switch (*CBfPtr) {
case '<':
if (++LStTop >= LPS_SIZE) {
ErrMsg(ERR_PDO);
DBGFEX(1,DbgFNm,"FAILURE");
return FAILURE;
}
LStack[LStTop].LIndex = INFINITE;
LStack[LStTop].LAddr = CBfPtr;
CmdMod = '\0';
break;
case '>':
if (LStTop == LStBot) {
ErrMsg(ERR_BNI);
DBGFEX(1,DbgFNm,"FAILURE");
return FAILURE;
}
--LStTop;
CmdMod = '\0';
break;
default:
if (SkpCmd() == FAILURE) {
DBGFEX(1,DbgFNm,"FAILURE, SkpCmd() failed");
return FAILURE;
}
} /* end of switch */
++CBfPtr;
} /* end of while (!='!')*/
/*
* At this point, we've found an '!'. if tracing is on, display exclamation
* point
*/
if (TraceM) { /* if trace mode is on */
if (CmdMod & ATSIGN) { /* if it was @O */
ZDspCh('@');
}
ZDspCh('!');
}
if (FindES('!') == FAILURE) { /* find end of tag */
DBGFEX(1,DbgFNm,"FAILURE, FindES() failed");
return FAILURE;
}
#if DEBUGGING
sprintf(DbgSBf,"found tag \"%.*s\"\n",(int)(CBfPtr-ArgPtr), ArgPtr);
DbgFMs(1,DbgFNm,DbgSBf);
#endif
/*
* compare found tag (in ArgPtr) to O command tag (in TBf).
*/
TagPtr = TBfBeg;
while ((TagPtr < TBfPtr) && (*ArgPtr == *TagPtr)) {
++ArgPtr;
++TagPtr;
}
Found = ((TagPtr == TBfPtr) && (*ArgPtr == '!'));
++CBfPtr;
} /* end of while (!Found) */
--CBfPtr;
CmdMod = '\0'; /* clear modifiers flags */
DBGFEX(1,DbgFNm,"SUCCESS");
return SUCCESS;
}