4.3BSD - /usr/src/bin/csh/sh.dol.c

   1: /*
   2:  * Copyright (c) 1980 Regents of the University of California.
   3:  * All rights reserved.  The Berkeley Software License Agreement
   4:  * specifies the terms and conditions for redistribution.
   5:  */
   6: 
   7: #ifndef lint
   8: static char *sccsid = "@(#)sh.dol.c	5.3 (Berkeley) 3/29/86";
   9: #endif
  10: 
  11: #include "sh.h"
  12: 
  13: /*
  14:  * C shell
  15:  */
  16: 
  17: /*
  18:  * These routines perform variable substitution and quoting via ' and ".
  19:  * To this point these constructs have been preserved in the divided
  20:  * input words.  Here we expand variables and turn quoting via ' and " into
  21:  * QUOTE bits on characters (which prevent further interpretation).
  22:  * If the `:q' modifier was applied during history expansion, then
  23:  * some QUOTEing may have occurred already, so we dont "trim()" here.
  24:  */
  25: 
  26: int Dpeekc, Dpeekrd;        /* Peeks for DgetC and Dreadc */
  27: char    *Dcp, **Dvp;            /* Input vector for Dreadc */
  28: 
  29: #define DEOF    -1
  30: 
  31: #define unDgetC(c)  Dpeekc = c
  32: 
  33: #define QUOTES      (_Q|_Q1|_ESC)   /* \ ' " ` */
  34: 
  35: /*
  36:  * The following variables give the information about the current
  37:  * $ expansion, recording the current word position, the remaining
  38:  * words within this expansion, the count of remaining words, and the
  39:  * information about any : modifier which is being applied.
  40:  */
  41: char    *dolp;          /* Remaining chars from this word */
  42: char    **dolnxt;       /* Further words */
  43: int dolcnt;         /* Count of further words */
  44: char    dolmod;         /* : modifier character */
  45: int dolmcnt;        /* :gx -> 10000, else 1 */
  46: 
  47: /*
  48:  * Fix up the $ expansions and quotations in the
  49:  * argument list to command t.
  50:  */
  51: Dfix(t)
  52:     register struct command *t;
  53: {
  54:     register char **pp;
  55:     register char *p;
  56: 
  57:     if (noexec)
  58:         return;
  59:     /* Note that t_dcom isn't trimmed thus !...:q's aren't lost */
  60:     for (pp = t->t_dcom; p = *pp++;)
  61:         while (*p)
  62:             if (cmap(*p++, _DOL|QUOTES)) {  /* $, \, ', ", ` */
  63:                 Dfix2(t->t_dcom);   /* found one */
  64:                 blkfree(t->t_dcom);
  65:                 t->t_dcom = gargv;
  66:                 gargv = 0;
  67:                 return;
  68:             }
  69: }
  70: 
  71: /*
  72:  * $ substitute one word, for i/o redirection
  73:  */
  74: char *
  75: Dfix1(cp)
  76:     register char *cp;
  77: {
  78:     char *Dv[2];
  79: 
  80:     if (noexec)
  81:         return (0);
  82:     Dv[0] = cp; Dv[1] = NOSTR;
  83:     Dfix2(Dv);
  84:     if (gargc != 1) {
  85:         setname(cp);
  86:         bferr("Ambiguous");
  87:     }
  88:     cp = savestr(gargv[0]);
  89:     blkfree(gargv), gargv = 0;
  90:     return (cp);
  91: }
  92: 
  93: /*
  94:  * Subroutine to do actual fixing after state initialization.
  95:  */
  96: Dfix2(v)
  97:     char **v;
  98: {
  99:     char *agargv[GAVSIZ];
 100: 
 101:     ginit(agargv);          /* Initialize glob's area pointers */
 102:     Dvp = v; Dcp = "";      /* Setup input vector for Dreadc */
 103:     unDgetC(0); unDredc(0);     /* Clear out any old peeks (at error) */
 104:     dolp = 0; dolcnt = 0;       /* Clear out residual $ expands (...) */
 105:     while (Dword())
 106:         continue;
 107:     gargv = copyblk(gargv);
 108: }
 109: 
 110: /*
 111:  * Get a word.  This routine is analogous to the routine
 112:  * word() in sh.lex.c for the main lexical input.  One difference
 113:  * here is that we don't get a newline to terminate our expansion.
 114:  * Rather, DgetC will return a DEOF when we hit the end-of-input.
 115:  */
 116: Dword()
 117: {
 118:     register int c, c1;
 119:     char wbuf[BUFSIZ];
 120:     register char *wp = wbuf;
 121:     register int i = BUFSIZ - 4;
 122:     register bool dolflg;
 123:     bool sofar = 0;
 124: 
 125: loop:
 126:     c = DgetC(DODOL);
 127:     switch (c) {
 128: 
 129:     case DEOF:
 130: deof:
 131:         if (sofar == 0)
 132:             return (0);
 133:         /* finish this word and catch the code above the next time */
 134:         unDredc(c);
 135:         /* fall into ... */
 136: 
 137:     case '\n':
 138:         *wp = 0;
 139:         goto ret;
 140: 
 141:     case ' ':
 142:     case '\t':
 143:         goto loop;
 144: 
 145:     case '`':
 146:         /* We preserve ` quotations which are done yet later */
 147:         *wp++ = c, --i;
 148:     case '\'':
 149:     case '"':
 150:         /*
 151: 		 * Note that DgetC never returns a QUOTES character
 152: 		 * from an expansion, so only true input quotes will
 153: 		 * get us here or out.
 154: 		 */
 155:         c1 = c;
 156:         dolflg = c1 == '"' ? DODOL : 0;
 157:         for (;;) {
 158:             c = DgetC(dolflg);
 159:             if (c == c1)
 160:                 break;
 161:             if (c == '\n' || c == DEOF)
 162:                 error("Unmatched %c", c1);
 163:             if ((c & (QUOTE|TRIM)) == ('\n' | QUOTE))
 164:                 --wp, ++i;
 165:             if (--i <= 0)
 166:                 goto toochars;
 167:             switch (c1) {
 168: 
 169:             case '"':
 170:                 /*
 171: 				 * Leave any `s alone for later.
 172: 				 * Other chars are all quoted, thus `...`
 173: 				 * can tell it was within "...".
 174: 				 */
 175:                 *wp++ = c == '`' ? '`' : c | QUOTE;
 176:                 break;
 177: 
 178:             case '\'':
 179:                 /* Prevent all further interpretation */
 180:                 *wp++ = c | QUOTE;
 181:                 break;
 182: 
 183:             case '`':
 184:                 /* Leave all text alone for later */
 185:                 *wp++ = c;
 186:                 break;
 187:             }
 188:         }
 189:         if (c1 == '`')
 190:             *wp++ = '`', --i;
 191:         goto pack;      /* continue the word */
 192: 
 193:     case '\\':
 194:         c = DgetC(0);       /* No $ subst! */
 195:         if (c == '\n' || c == DEOF)
 196:             goto loop;
 197:         c |= QUOTE;
 198:         break;
 199:     }
 200:     unDgetC(c);
 201: pack:
 202:     sofar = 1;
 203:     /* pack up more characters in this word */
 204:     for (;;) {
 205:         c = DgetC(DODOL);
 206:         if (c == '\\') {
 207:             c = DgetC(0);
 208:             if (c == DEOF)
 209:                 goto deof;
 210:             if (c == '\n')
 211:                 c = ' ';
 212:             else
 213:                 c |= QUOTE;
 214:         }
 215:         if (c == DEOF)
 216:             goto deof;
 217:         if (cmap(c, _SP|_NL|_Q|_Q1)) {      /* sp \t\n'"` */
 218:             unDgetC(c);
 219:             if (cmap(c, QUOTES))
 220:                 goto loop;
 221:             *wp++ = 0;
 222:             goto ret;
 223:         }
 224:         if (--i <= 0)
 225: toochars:
 226:             error("Word too long");
 227:         *wp++ = c;
 228:     }
 229: ret:
 230:     Gcat("", wbuf);
 231:     return (1);
 232: }
 233: 
 234: /*
 235:  * Get a character, performing $ substitution unless flag is 0.
 236:  * Any QUOTES character which is returned from a $ expansion is
 237:  * QUOTEd so that it will not be recognized above.
 238:  */
 239: DgetC(flag)
 240:     register int flag;
 241: {
 242:     register int c;
 243: 
 244: top:
 245:     if (c = Dpeekc) {
 246:         Dpeekc = 0;
 247:         return (c);
 248:     }
 249:     if (lap) {
 250:         c = *lap++ & (QUOTE|TRIM);
 251:         if (c == 0) {
 252:             lap = 0;
 253:             goto top;
 254:         }
 255: quotspec:
 256:         if (cmap(c, QUOTES))
 257:             return (c | QUOTE);
 258:         return (c);
 259:     }
 260:     if (dolp) {
 261:         if (c = *dolp++ & (QUOTE|TRIM))
 262:             goto quotspec;
 263:         if (dolcnt > 0) {
 264:             setDolp(*dolnxt++);
 265:             --dolcnt;
 266:             return (' ');
 267:         }
 268:         dolp = 0;
 269:     }
 270:     if (dolcnt > 0) {
 271:         setDolp(*dolnxt++);
 272:         --dolcnt;
 273:         goto top;
 274:     }
 275:     c = Dredc();
 276:     if (c == '$' && flag) {
 277:         Dgetdol();
 278:         goto top;
 279:     }
 280:     return (c);
 281: }
 282: 
 283: char    *nulvec[] = { 0 };
 284: struct  varent nulargv = { nulvec, "argv", 0 };
 285: 
 286: /*
 287:  * Handle the multitudinous $ expansion forms.
 288:  * Ugh.
 289:  */
 290: Dgetdol()
 291: {
 292:     register char *np;
 293:     register struct varent *vp;
 294:     char name[20];
 295:     int c, sc;
 296:     int subscr = 0, lwb = 1, upb = 0;
 297:     bool dimen = 0, bitset = 0;
 298:     char wbuf[BUFSIZ];
 299: 
 300:     dolmod = dolmcnt = 0;
 301:     c = sc = DgetC(0);
 302:     if (c == '{')
 303:         c = DgetC(0);       /* sc is { to take } later */
 304:     if ((c & TRIM) == '#')
 305:         dimen++, c = DgetC(0);      /* $# takes dimension */
 306:     else if (c == '?')
 307:         bitset++, c = DgetC(0);     /* $? tests existence */
 308:     switch (c) {
 309: 
 310:     case '$':
 311:         if (dimen || bitset)
 312:             goto syntax;        /* No $?$, $#$ */
 313:         setDolp(doldol);
 314:         goto eatbrac;
 315: 
 316:     case '<'|QUOTE:
 317:         if (dimen || bitset)
 318:             goto syntax;        /* No $?<, $#< */
 319:         for (np = wbuf; read(OLDSTD, np, 1) == 1; np++) {
 320:             if (np >= &wbuf[BUFSIZ-1])
 321:                 error("$< line too long");
 322:             if (*np <= 0 || *np == '\n')
 323:                 break;
 324:         }
 325:         *np = 0;
 326:         /*
 327: 		 * KLUDGE: dolmod is set here because it will
 328: 		 * cause setDolp to call domod and thus to copy wbuf.
 329: 		 * Otherwise setDolp would use it directly. If we saved
 330: 		 * it ourselves, no one would know when to free it.
 331: 		 * The actual function of the 'q' causes filename
 332: 		 * expansion not to be done on the interpolated value.
 333: 		 */
 334:         dolmod = 'q';
 335:         dolmcnt = 10000;
 336:         setDolp(wbuf);
 337:         goto eatbrac;
 338: 
 339:     case DEOF:
 340:     case '\n':
 341:         goto syntax;
 342: 
 343:     case '*':
 344:         (void) strcpy(name, "argv");
 345:         vp = adrof("argv");
 346:         subscr = -1;            /* Prevent eating [...] */
 347:         break;
 348: 
 349:     default:
 350:         np = name;
 351:         if (digit(c)) {
 352:             if (dimen)
 353:                 goto syntax;    /* No $#1, e.g. */
 354:             subscr = 0;
 355:             do {
 356:                 subscr = subscr * 10 + c - '0';
 357:                 c = DgetC(0);
 358:             } while (digit(c));
 359:             unDredc(c);
 360:             if (subscr < 0)
 361:                 goto oob;
 362:             if (subscr == 0) {
 363:                 if (bitset) {
 364:                     dolp = file ? "1" : "0";
 365:                     goto eatbrac;
 366:                 }
 367:                 if (file == 0)
 368:                     error("No file for $0");
 369:                 setDolp(file);
 370:                 goto eatbrac;
 371:             }
 372:             if (bitset)
 373:                 goto syntax;
 374:             vp = adrof("argv");
 375:             if (vp == 0) {
 376:                 vp = &nulargv;
 377:                 goto eatmod;
 378:             }
 379:             break;
 380:         }
 381:         if (!alnum(c))
 382:             goto syntax;
 383:         for (;;) {
 384:             *np++ = c;
 385:             c = DgetC(0);
 386:             if (!alnum(c))
 387:                 break;
 388:             if (np >= &name[sizeof name - 2])
 389: syntax:
 390:                 error("Variable syntax");
 391:         }
 392:         *np++ = 0;
 393:         unDredc(c);
 394:         vp = adrof(name);
 395:     }
 396:     if (bitset) {
 397:         dolp = (vp || getenv(name)) ? "1" : "0";
 398:         goto eatbrac;
 399:     }
 400:     if (vp == 0) {
 401:         np = getenv(name);
 402:         if (np) {
 403:             addla(np);
 404:             goto eatbrac;
 405:         }
 406:         udvar(name);
 407:         /*NOTREACHED*/
 408:     }
 409:     c = DgetC(0);
 410:     upb = blklen(vp->vec);
 411:     if (dimen == 0 && subscr == 0 && c == '[') {
 412:         np = name;
 413:         for (;;) {
 414:             c = DgetC(DODOL);   /* Allow $ expand within [ ] */
 415:             if (c == ']')
 416:                 break;
 417:             if (c == '\n' || c == DEOF)
 418:                 goto syntax;
 419:             if (np >= &name[sizeof name - 2])
 420:                 goto syntax;
 421:             *np++ = c;
 422:         }
 423:         *np = 0, np = name;
 424:         if (dolp || dolcnt)     /* $ exp must end before ] */
 425:             goto syntax;
 426:         if (!*np)
 427:             goto syntax;
 428:         if (digit(*np)) {
 429:             register int i = 0;
 430: 
 431:             while (digit(*np))
 432:                 i = i * 10 + *np++ - '0';
 433:             if ((i < 0 || i > upb) && !any(*np, "-*")) {
 434: oob:
 435:                 setname(vp->v_name);
 436:                 error("Subscript out of range");
 437:             }
 438:             lwb = i;
 439:             if (!*np)
 440:                 upb = lwb, np = "*";
 441:         }
 442:         if (*np == '*')
 443:             np++;
 444:         else if (*np != '-')
 445:             goto syntax;
 446:         else {
 447:             register int i = upb;
 448: 
 449:             np++;
 450:             if (digit(*np)) {
 451:                 i = 0;
 452:                 while (digit(*np))
 453:                     i = i * 10 + *np++ - '0';
 454:                 if (i < 0 || i > upb)
 455:                     goto oob;
 456:             }
 457:             if (i < lwb)
 458:                 upb = lwb - 1;
 459:             else
 460:                 upb = i;
 461:         }
 462:         if (lwb == 0) {
 463:             if (upb != 0)
 464:                 goto oob;
 465:             upb = -1;
 466:         }
 467:         if (*np)
 468:             goto syntax;
 469:     } else {
 470:         if (subscr > 0)
 471:             if (subscr > upb)
 472:                 lwb = 1, upb = 0;
 473:             else
 474:                 lwb = upb = subscr;
 475:         unDredc(c);
 476:     }
 477:     if (dimen) {
 478:         char *cp = putn(upb - lwb + 1);
 479: 
 480:         addla(cp);
 481:         xfree(cp);
 482:     } else {
 483: eatmod:
 484:         c = DgetC(0);
 485:         if (c == ':') {
 486:             c = DgetC(0), dolmcnt = 1;
 487:             if (c == 'g')
 488:                 c = DgetC(0), dolmcnt = 10000;
 489:             if (!any(c, "htrqxe"))
 490:                 error("Bad : mod in $");
 491:             dolmod = c;
 492:             if (c == 'q')
 493:                 dolmcnt = 10000;
 494:         } else
 495:             unDredc(c);
 496:         dolnxt = &vp->vec[lwb - 1];
 497:         dolcnt = upb - lwb + 1;
 498:     }
 499: eatbrac:
 500:     if (sc == '{') {
 501:         c = Dredc();
 502:         if (c != '}')
 503:             goto syntax;
 504:     }
 505: }
 506: 
 507: setDolp(cp)
 508:     register char *cp;
 509: {
 510:     register char *dp;
 511: 
 512:     if (dolmod == 0 || dolmcnt == 0) {
 513:         dolp = cp;
 514:         return;
 515:     }
 516:     dp = domod(cp, dolmod);
 517:     if (dp) {
 518:         dolmcnt--;
 519:         addla(dp);
 520:         xfree(dp);
 521:     } else
 522:         addla(cp);
 523:     dolp = "";
 524: }
 525: 
 526: unDredc(c)
 527:     int c;
 528: {
 529: 
 530:     Dpeekrd = c;
 531: }
 532: 
 533: Dredc()
 534: {
 535:     register int c;
 536: 
 537:     if (c = Dpeekrd) {
 538:         Dpeekrd = 0;
 539:         return (c);
 540:     }
 541:     if (Dcp && (c = *Dcp++))
 542:         return (c&(QUOTE|TRIM));
 543:     if (*Dvp == 0) {
 544:         Dcp = 0;
 545:         return (DEOF);
 546:     }
 547:     Dcp = *Dvp++;
 548:     return (' ');
 549: }
 550: 
 551: Dtestq(c)
 552:     register int c;
 553: {
 554: 
 555:     if (cmap(c, QUOTES))
 556:         gflag = 1;
 557: }
 558: 
 559: /*
 560:  * Form a shell temporary file (in unit 0) from the words
 561:  * of the shell input up to a line the same as "term".
 562:  * Unit 0 should have been closed before this call.
 563:  */
 564: heredoc(term)
 565:     char *term;
 566: {
 567:     register int c;
 568:     char *Dv[2];
 569:     char obuf[BUFSIZ], lbuf[BUFSIZ], mbuf[BUFSIZ];
 570:     int ocnt, lcnt, mcnt;
 571:     register char *lbp, *obp, *mbp;
 572:     char **vp;
 573:     bool quoted;
 574: 
 575:     if (creat(shtemp, 0600) < 0)
 576:         Perror(shtemp);
 577:     (void) close(0);
 578:     if (open(shtemp, 2) < 0) {
 579:         int oerrno = errno;
 580: 
 581:         (void) unlink(shtemp);
 582:         errno = oerrno;
 583:         Perror(shtemp);
 584:     }
 585:     (void) unlink(shtemp);          /* 0 0 inode! */
 586:     Dv[0] = term; Dv[1] = NOSTR; gflag = 0;
 587:     trim(Dv); rscan(Dv, Dtestq); quoted = gflag;
 588:     ocnt = BUFSIZ; obp = obuf;
 589:     for (;;) {
 590:         /*
 591: 		 * Read up a line
 592: 		 */
 593:         lbp = lbuf; lcnt = BUFSIZ - 4;
 594:         for (;;) {
 595:             c = readc(1);       /* 1 -> Want EOF returns */
 596:             if (c < 0) {
 597:                 setname(term);
 598:                 bferr("<< terminator not found");
 599:             }
 600:             if (c == '\n')
 601:                 break;
 602:             if (c &= TRIM) {
 603:                 *lbp++ = c;
 604:                 if (--lcnt < 0) {
 605:                     setname("<<");
 606:                     error("Line overflow");
 607:                 }
 608:             }
 609:         }
 610:         *lbp = 0;
 611: 
 612:         /*
 613: 		 * Compare to terminator -- before expansion
 614: 		 */
 615:         if (eq(lbuf, term)) {
 616:             (void) write(0, obuf, BUFSIZ - ocnt);
 617:             (void) lseek(0, (off_t)0, 0);
 618:             return;
 619:         }
 620: 
 621:         /*
 622: 		 * If term was quoted or -n just pass it on
 623: 		 */
 624:         if (quoted || noexec) {
 625:             *lbp++ = '\n'; *lbp = 0;
 626:             for (lbp = lbuf; c = *lbp++;) {
 627:                 *obp++ = c;
 628:                 if (--ocnt == 0) {
 629:                     (void) write(0, obuf, BUFSIZ);
 630:                     obp = obuf; ocnt = BUFSIZ;
 631:                 }
 632:             }
 633:             continue;
 634:         }
 635: 
 636:         /*
 637: 		 * Term wasn't quoted so variable and then command
 638: 		 * expand the input line
 639: 		 */
 640:         Dcp = lbuf; Dvp = Dv + 1; mbp = mbuf; mcnt = BUFSIZ - 4;
 641:         for (;;) {
 642:             c = DgetC(DODOL);
 643:             if (c == DEOF)
 644:                 break;
 645:             if ((c &= TRIM) == 0)
 646:                 continue;
 647:             /* \ quotes \ $ ` here */
 648:             if (c =='\\') {
 649:                 c = DgetC(0);
 650:                 if (!any(c, "$\\`"))
 651:                     unDgetC(c | QUOTE), c = '\\';
 652:                 else
 653:                     c |= QUOTE;
 654:             }
 655:             *mbp++ = c;
 656:             if (--mcnt == 0) {
 657:                 setname("<<");
 658:                 bferr("Line overflow");
 659:             }
 660:         }
 661:         *mbp++ = 0;
 662: 
 663:         /*
 664: 		 * If any ` in line do command substitution
 665: 		 */
 666:         mbp = mbuf;
 667:         if (any('`', mbp)) {
 668:             /*
 669: 			 * 1 arg to dobackp causes substitution to be literal.
 670: 			 * Words are broken only at newlines so that all blanks
 671: 			 * and tabs are preserved.  Blank lines (null words)
 672: 			 * are not discarded.
 673: 			 */
 674:             vp = dobackp(mbuf, 1);
 675:         } else
 676:             /* Setup trivial vector similar to return of dobackp */
 677:             Dv[0] = mbp, Dv[1] = NOSTR, vp = Dv;
 678: 
 679:         /*
 680: 		 * Resurrect the words from the command substitution
 681: 		 * each separated by a newline.  Note that the last
 682: 		 * newline of a command substitution will have been
 683: 		 * discarded, but we put a newline after the last word
 684: 		 * because this represents the newline after the last
 685: 		 * input line!
 686: 		 */
 687:         for (; *vp; vp++) {
 688:             for (mbp = *vp; *mbp; mbp++) {
 689:                 *obp++ = *mbp & TRIM;
 690:                 if (--ocnt == 0) {
 691:                     (void) write(0, obuf, BUFSIZ);
 692:                     obp = obuf; ocnt = BUFSIZ;
 693:                 }
 694:             }
 695:             *obp++ = '\n';
 696:             if (--ocnt == 0) {
 697:                 (void) write(0, obuf, BUFSIZ);
 698:                 obp = obuf; ocnt = BUFSIZ;
 699:             }
 700:         }
 701:         if (pargv)
 702:             blkfree(pargv), pargv = 0;
 703:     }
 704: }

Defined functions

Defined variables

Defined macros