1 /* $Header: /p/tcsh/cvsroot/tcsh/sh.exp.c,v 3.53 2007/10/01 19:09:28 christos Exp $ */
3 * sh.exp.c: Expression evaluations
6 * Copyright (c) 1980, 1991 The Regents of the University of California.
9 * Redistribution and use in source and binary forms, with or without
10 * modification, are permitted provided that the following conditions
12 * 1. Redistributions of source code must retain the above copyright
13 * notice, this list of conditions and the following disclaimer.
14 * 2. Redistributions in binary form must reproduce the above copyright
15 * notice, this list of conditions and the following disclaimer in the
16 * documentation and/or other materials provided with the distribution.
17 * 3. Neither the name of the University nor the names of its contributors
18 * may be used to endorse or promote products derived from this software
19 * without specific prior written permission.
21 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
22 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
23 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
24 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
25 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
26 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
27 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
28 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
29 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
30 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
35 RCSID("$tcsh: sh.exp.c,v 3.53 2007/10/01 19:09:28 christos Exp $")
43 #define TEXP_IGNORE 1 /* in ignore, it means to ignore value, just parse */
44 #define TEXP_NOGLOB 2 /* in ignore, it means not to globone */
60 static int sh_access (const Char *, int);
61 static int exp1 (Char ***, int);
62 static int exp2x (Char ***, int);
63 static int exp2a (Char ***, int);
64 static int exp2b (Char ***, int);
65 static int exp2c (Char ***, int);
66 static Char *exp3 (Char ***, int);
67 static Char *exp3a (Char ***, int);
68 static Char *exp4 (Char ***, int);
69 static Char *exp5 (Char ***, int);
70 static Char *exp6 (Char ***, int);
71 static void evalav (Char **);
72 static int isa (Char *, int);
73 static int egetn (Char *);
76 static void etracc (const char *, const Char *, Char ***);
77 static void etraci (const char *, int, Char ***);
79 #define etracc(A, B, C) ((void)0)
80 #define etraci(A, B, C) ((void)0)
84 * shell access function according to POSIX and non POSIX
85 * From Beto Appleton (beto@aixwiz.aix.ibm.com)
88 sh_access(const Char *fname, int mode)
90 #if defined(POSIX) && !defined(USE_ACCESS)
93 char *name = short2str(fname);
98 #if !defined(POSIX) || defined(USE_ACCESS)
99 return access(name, mode);
104 * -r file True if file exists and is readable.
105 * -w file True if file exists and is writable.
106 * True shall indicate only that the write flag is on.
107 * The file shall not be writable on a read-only file
108 * system even if this test indicates true.
109 * -x file True if file exists and is executable.
110 * True shall indicate only that the execute flag is on.
111 * If file is a directory, true indicates that the file
114 if (mode != W_OK && mode != X_OK)
115 return access(name, mode);
117 if (stat(name, &statb) == -1)
120 if (access(name, mode) == 0) {
122 if (S_ISDIR(statb.st_mode) && mode == X_OK)
126 /* root needs permission for someone */
129 mode = S_IWUSR | S_IWGRP | S_IWOTH;
132 mode = S_IXUSR | S_IXGRP | S_IXOTH;
141 else if (euid == statb.st_uid)
144 else if (egid == statb.st_gid)
149 /* you can be in several groups */
154 * Try these things to find a positive maximum groups value:
155 * 1) sysconf(_SC_NGROUPS_MAX)
157 * 3) getgroups(0, unused)
158 * Then allocate and scan the groups array if one of these worked.
160 # if defined (HAVE_SYSCONF) && defined (_SC_NGROUPS_MAX)
161 if ((n = sysconf(_SC_NGROUPS_MAX)) == -1)
162 # endif /* _SC_NGROUPS_MAX */
165 n = getgroups(0, (GETGROUPS_T *) NULL);
168 groups = xmalloc(n * sizeof(*groups));
169 n = getgroups((int) n, groups);
171 if (groups[n] == statb.st_gid) {
177 # endif /* NGROUPS_MAX */
179 if (statb.st_mode & mode)
189 return (exp0(vp, 0));
193 exp0(Char ***vp, int ignore)
195 int p1 = exp1(vp, ignore);
197 etraci("exp0 p1", p1, vp);
198 while (**vp && eq(**vp, STRor2)) {
204 exp0(vp, (ignore & TEXP_IGNORE) || p1) :
205 exp1(vp, (ignore & TEXP_IGNORE) || p1);
206 if (compat_expr || !(ignore & TEXP_IGNORE))
208 etraci("exp0 p1", p1, vp);
216 exp1(Char ***vp, int ignore)
218 int p1 = exp2x(vp, ignore);
220 etraci("exp1 p1", p1, vp);
221 while (**vp && eq(**vp, STRand2)) {
226 exp1(vp, (ignore & TEXP_IGNORE) || !p1) :
227 exp2x(vp, (ignore & TEXP_IGNORE) || !p1);
229 etraci("exp1 p2", p2, vp);
230 if (compat_expr || !(ignore & TEXP_IGNORE))
232 etraci("exp1 p1", p1, vp);
240 exp2x(Char ***vp, int ignore)
242 int p1 = exp2a(vp, ignore);
244 etraci("exp2x p1", p1, vp);
245 while (**vp && eq(**vp, STRor)) {
252 etraci("exp2x p2", p2, vp);
253 if (compat_expr || !(ignore & TEXP_IGNORE))
255 etraci("exp2x p1", p1, vp);
263 exp2a(Char ***vp, int ignore)
265 int p1 = exp2b(vp, ignore);
267 etraci("exp2a p1", p1, vp);
268 while (**vp && eq(**vp, STRcaret)) {
275 etraci("exp2a p2", p2, vp);
276 if (compat_expr || !(ignore & TEXP_IGNORE))
278 etraci("exp2a p1", p1, vp);
286 exp2b(Char ***vp, int ignore)
288 int p1 = exp2c(vp, ignore);
290 etraci("exp2b p1", p1, vp);
291 while (**vp && eq(**vp, STRand)) {
298 etraci("exp2b p2", p2, vp);
299 if (compat_expr || !(ignore & TEXP_IGNORE))
301 etraci("exp2b p1", p1, vp);
309 exp2c(Char ***vp, int ignore)
311 Char *p1 = exp3(vp, ignore);
315 cleanup_push(p1, xfree);
316 etracc("exp2c p1", p1, vp);
317 if ((i = isa(**vp, EQOP)) != 0) {
319 if (i == EQMATCH || i == NOTEQMATCH)
320 ignore |= TEXP_NOGLOB;
321 p2 = exp3(vp, ignore);
322 cleanup_push(p2, xfree);
323 etracc("exp2c p2", p2, vp);
324 if (!(ignore & TEXP_IGNORE))
352 exp3(Char ***vp, int ignore)
357 p1 = exp3a(vp, ignore);
358 etracc("exp3 p1", p1, vp);
359 while ((i = isa(**vp, RELOP)) != 0) {
361 if (**vp && eq(**vp, STRequal))
363 cleanup_push(p1, xfree);
367 cleanup_push(p2, xfree);
368 etracc("exp3 p2", p2, vp);
369 if (!(ignore & TEXP_IGNORE))
373 i = egetn(p1) > egetn(p2);
377 i = egetn(p1) >= egetn(p2);
381 i = egetn(p1) < egetn(p2);
385 i = egetn(p1) <= egetn(p2);
390 etracc("exp3 p1", p1, vp);
398 exp3a(Char ***vp, int ignore)
404 p1 = exp4(vp, ignore);
405 etracc("exp3a p1", p1, vp);
407 if (op && any("<>", op[0]) && op[0] == op[1]) {
409 cleanup_push(p1, xfree);
413 cleanup_push(p2, xfree);
414 etracc("exp3a p2", p2, vp);
416 i = egetn(p1) << egetn(p2);
418 i = egetn(p1) >> egetn(p2);
421 etracc("exp3a p1", p1, vp);
427 exp4(Char ***vp, int ignore)
432 p1 = exp5(vp, ignore);
433 etracc("exp4 p1", p1, vp);
434 while (isa(**vp, ADDOP)) {
435 const Char *op = *(*vp)++;
437 cleanup_push(p1, xfree);
441 cleanup_push(p2, xfree);
442 etracc("exp4 p2", p2, vp);
443 if (!(ignore & TEXP_IGNORE))
447 i = egetn(p1) + egetn(p2);
451 i = egetn(p1) - egetn(p2);
456 etracc("exp4 p1", p1, vp);
464 exp5(Char ***vp, int ignore)
469 p1 = exp6(vp, ignore);
470 etracc("exp5 p1", p1, vp);
472 while (isa(**vp, MULOP)) {
473 const Char *op = *(*vp)++;
474 if ((ignore & TEXP_NOGLOB) != 0) {
476 * We are just trying to get the right side of
477 * a =~ or !~ operator
483 cleanup_push(p1, xfree);
487 cleanup_push(p2, xfree);
488 etracc("exp5 p2", p2, vp);
489 if (!(ignore & TEXP_IGNORE))
493 i = egetn(p1) * egetn(p2);
512 etracc("exp5 p1", p1, vp);
520 exp6(Char ***vp, int ignore)
526 stderror(ERR_NAME | ERR_EXPRESSION);
527 if (eq(**vp, STRbang)) {
529 cp = exp6(vp, ignore);
530 cleanup_push(cp, xfree);
531 etracc("exp6 ! cp", cp, vp);
536 if (eq(**vp, STRtilde)) {
538 cp = exp6(vp, ignore);
539 cleanup_push(cp, xfree);
540 etracc("exp6 ~ cp", cp, vp);
545 if (eq(**vp, STRLparen)) {
547 ccode = exp0(vp, ignore);
548 etraci("exp6 () ccode", ccode, vp);
549 if (**vp == 0 || ***vp != ')')
550 stderror(ERR_NAME | ERR_EXPRESSION);
552 return (putn(ccode));
554 if (eq(**vp, STRLbrace)) {
556 struct command faket;
559 faket.t_dtyp = NODE_COMMAND;
560 faket.t_dflg = F_BACKQ;
561 faket.t_dcar = faket.t_dcdr = faket.t_dspr = NULL;
562 faket.t_dcom = fakecom;
563 fakecom[0] = STRfakecom;
569 stderror(ERR_NAME | ERR_MISSING, '}');
570 if (eq(*(*vp)++, STRRbrace))
573 if (ignore & TEXP_IGNORE)
574 return (Strsave(STRNULL));
576 cleanup_push(&faket, psavejob_cleanup); /* faket is only a marker */
577 if (pfork(&faket, -1) == 0) {
583 cleanup_until(&faket);
584 etraci("exp6 {} status", egetn(varval(STRstatus)), vp);
585 return (putn(egetn(varval(STRstatus)) == 0));
587 if (isa(**vp, ANYOP))
588 return (Strsave(STRNULL));
591 # define FILETESTS "erwxfdzoplstSXLbcugkmKR"
593 # define FILETESTS "erwxfdzoplstSXLbcugkmK"
595 #define FILEVALS "ZAMCDIUGNFPL"
596 if (*cp == '-' && (any(FILETESTS, cp[1]) || any(FILEVALS, cp[1])))
597 return(filetest(cp, vp, ignore));
598 etracc("exp6 default", cp, vp);
599 return (ignore & TEXP_NOGLOB ? Strsave(cp) : globone(cp, G_APPEND));
604 * Extended file tests
605 * From: John Rowe <rowe@excc.exeter.ac.uk>
608 filetest(Char *cp, Char ***vp, int ignore)
611 struct cvxstat stb, *st = NULL;
612 # define TCSH_STAT stat64
614 # define TCSH_STAT stat
615 struct stat stb, *st = NULL;
620 struct cvxstat lstb, *lst = NULL;
621 # define TCSH_LSTAT lstat64
623 # define TCSH_LSTAT lstat
624 struct stat lstb, *lst = NULL;
630 unsigned pmask = 0xffff;
632 Char *ft = cp, *dp, *ep, *strdev, *strino, *strF, *str, valtest = '\0',
634 char *string, string0[8];
639 while(any(FILETESTS, *++ft))
642 if (!*ft && *(ft - 1) == 'L')
645 if (any(FILEVALS, *ft)) {
648 * Value tests return '-1' on failure as 0 is
649 * a legitimate value for many of them.
650 * 'F' returns ':' for compatibility.
652 errval = valtest == 'F' ? STRcolon : STRminus1;
654 if (valtest == 'P' && *ft >= '0' && *ft <= '7') {
655 pmask = (char) *ft - '0';
656 while ( *++ft >= '0' && *ft <= '7' )
657 pmask = 8 * pmask + ((char) *ft - '0');
659 if (Strcmp(ft, STRcolon) == 0 && any("AMCUGP", valtest)) {
665 if (*ft || ft == cp + 1)
666 stderror(ERR_NAME | ERR_FILEINQ);
669 * Detect missing file names by checking for operator in the file name
670 * position. However, if an operator name appears there, we must make
671 * sure that there's no file by that name (e.g., "/") before announcing
672 * an error. Even this check isn't quite right, since it doesn't take
673 * globbing into account.
676 if (isa(**vp, ANYOP) && TCSH_STAT(short2str(**vp), &stb))
677 stderror(ERR_NAME | ERR_FILENAME);
680 if (ignore & TEXP_IGNORE)
681 return (Strsave(STRNULL));
682 ep = globone(dp, G_APPEND);
683 cleanup_push(ep, xfree);
689 i = !sh_access(ep, R_OK);
693 i = !sh_access(ep, W_OK);
697 i = !sh_access(ep, X_OK);
700 case 'X': /* tcsh extension, name is an executable in the path
701 * or a tcsh builtin command
706 case 't': /* SGI extension, true when file is a tty */
707 i = isatty(atoi(short2str(ep)));
713 if (tolower(*ft) == 'l') {
715 * avoid convex compiler bug.
719 if (TCSH_LSTAT(short2str(ep), lst) == -1) {
721 return (Strsave(errval));
730 * avoid convex compiler bug.
734 if (TCSH_STAT(short2str(ep), st) == -1) {
736 return (Strsave(errval));
744 i = S_ISREG(st->st_mode);
752 i = S_ISDIR(st->st_mode);
760 i = S_ISFIFO(st->st_mode);
761 #else /* !S_ISFIFO */
763 #endif /* S_ISFIFO */
768 i = S_ISOFL(st->st_dm_mode);
785 i = S_ISLNK(lst->st_mode);
793 i = S_ISSOCK(st->st_mode);
794 # else /* !S_ISSOCK */
796 # endif /* S_ISSOCK */
801 i = S_ISBLK(st->st_mode);
809 i = S_ISCHR(st->st_mode);
816 i = (S_ISUID & st->st_mode) != 0;
820 i = (S_ISGID & st->st_mode) != 0;
824 i = (S_ISVTX & st->st_mode) != 0;
828 i = st->st_size == 0;
833 i = (stb.st_dmonflags & IMIGRATED) == IMIGRATED;
838 i = stb.st_size != 0;
846 i = st->st_uid == uid;
850 * Value operators are a tcsh extension.
854 i = (int) st->st_dev;
858 i = (int) st->st_ino;
862 strdev = putn( (int) st->st_dev);
863 strino = putn( (int) st->st_ino);
864 strF = xmalloc((2 + Strlen(strdev) + Strlen(strino))
866 (void) Strcat(Strcat(Strcpy(strF, strdev), STRcolon), strino);
878 filnam = short2str(ep);
879 string = areadlink(filnam);
880 strF = string == NULL ? errval : str2short(string);
883 return(Strsave(strF));
892 i = (int) st->st_nlink;
896 string = string0 + 1;
897 (void) xsnprintf(string, sizeof(string0) - 1, "%o",
898 pmask & (unsigned int)
899 ((S_IRWXU|S_IRWXG|S_IRWXO|S_ISUID|S_ISGID) & st->st_mode));
900 if (altout && *string != '0')
903 return(Strsave(str2short(string)));
906 if (altout && (pw = xgetpwuid(st->st_uid))) {
908 return(Strsave(str2short(pw->pw_name)));
910 i = (int) st->st_uid;
914 if (altout && (gr = xgetgrgid(st->st_gid))) {
916 return(Strsave(str2short(gr->gr_name)));
918 i = (int) st->st_gid;
922 i = (int) st->st_size;
925 case 'A': case 'M': case 'C':
926 footime = *ft == 'A' ? st->st_atime :
927 *ft == 'M' ? st->st_mtime : st->st_ctime;
929 strF = str2short(ctime(&footime));
930 if ((str = Strchr(strF, '\n')) != NULL)
933 return(Strsave(strF));
941 etraci("exp6 -? i", i, vp);
950 struct wordent paraml1;
951 struct wordent *hp = ¶ml1;
953 struct wordent *wdp = hp;
955 setcopy(STRstatus, STR0, VAR_READWRITE);
956 hp->prev = hp->next = hp;
959 struct wordent *new = xcalloc(1, sizeof *wdp);
965 wdp->word = Strsave(*v++);
968 cleanup_push(¶ml1, lex_cleanup);
970 t = syntax(paraml1.next, ¶ml1, 0);
971 cleanup_push(t, syntax_cleanup);
974 execute(t, -1, NULL, NULL, TRUE);
975 cleanup_until(¶ml1);
979 isa(Char *cp, int what)
982 return ((what & RESTOP) != 0);
986 if (what & ADDOP && (*cp == '+' || *cp == '-'))
988 if (what & MULOP && (*cp == '*' || *cp == '/' || *cp == '%'))
990 if (what & RESTOP && (*cp == '(' || *cp == ')' || *cp == '!' ||
991 *cp == '~' || *cp == '^' || *cp == '"'))
994 else if (cp[2] == 0) {
996 if (cp[0] == '|' && cp[1] == '&')
998 if (cp[0] == '<' && cp[1] == '<')
1000 if (cp[0] == '>' && cp[1] == '>')
1010 else if (cp[0] == '!') {
1014 return (NOTEQMATCH);
1030 if (*cp && *cp != '-' && !Isdigit(*cp))
1031 stderror(ERR_NAME | ERR_EXPRESSION);
1039 etraci(const char *str, int i, Char ***vp)
1041 xprintf("%s=%d\t", str, i);
1046 etracc(const char *str, const Char *cp, Char ***vp)
1048 xprintf("%s=%S\t", str, cp);