2 * sh.exp.c: Expression evaluations
5 * Copyright (c) 1980, 1991 The Regents of the University of California.
8 * Redistribution and use in source and binary forms, with or without
9 * modification, are permitted provided that the following conditions
11 * 1. Redistributions of source code must retain the above copyright
12 * notice, this list of conditions and the following disclaimer.
13 * 2. Redistributions in binary form must reproduce the above copyright
14 * notice, this list of conditions and the following disclaimer in the
15 * documentation and/or other materials provided with the distribution.
16 * 3. Neither the name of the University nor the names of its contributors
17 * may be used to endorse or promote products derived from this software
18 * without specific prior written permission.
20 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
21 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
22 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
23 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
24 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
25 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
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39 #define TEXP_IGNORE 1 /* in ignore, it means to ignore value, just parse */
40 #define TEXP_NOGLOB 2 /* in ignore, it means not to globone */
56 static int sh_access (const Char *, int);
57 static tcsh_number_t exp1 (Char ***, int);
58 static tcsh_number_t exp2x (Char ***, int);
59 static tcsh_number_t exp2a (Char ***, int);
60 static tcsh_number_t exp2b (Char ***, int);
61 static tcsh_number_t exp2c (Char ***, int);
62 static Char *exp3 (Char ***, int);
63 static Char *exp3a (Char ***, int);
64 static Char *exp4 (Char ***, int);
65 static Char *exp5 (Char ***, int);
66 static Char *exp6 (Char ***, int);
67 static void evalav (Char **);
68 static int isa (Char *, int);
69 static tcsh_number_t egetn (const Char *);
72 static void etracc (const char *, const Char *, Char ***);
73 static void etraci (const char *, tcsh_number_t, Char ***);
75 #define etracc(A, B, C) ((void)0)
76 #define etraci(A, B, C) ((void)0)
80 * shell access function according to POSIX and non POSIX
81 * From Beto Appleton (beto@aixwiz.aix.ibm.com)
84 sh_access(const Char *fname, int mode)
86 #if defined(POSIX) && !defined(USE_ACCESS)
89 char *name = short2str(fname);
94 #if !defined(POSIX) || defined(USE_ACCESS)
95 return access(name, mode);
100 * -r file True if file exists and is readable.
101 * -w file True if file exists and is writable.
102 * True shall indicate only that the write flag is on.
103 * The file shall not be writable on a read-only file
104 * system even if this test indicates true.
105 * -x file True if file exists and is executable.
106 * True shall indicate only that the execute flag is on.
107 * If file is a directory, true indicates that the file
110 if (mode != W_OK && mode != X_OK)
111 return access(name, mode);
113 if (stat(name, &statb) == -1)
116 if (access(name, mode) == 0) {
118 if (S_ISDIR(statb.st_mode) && mode == X_OK)
122 /* root needs permission for someone */
125 mode = S_IWUSR | S_IWGRP | S_IWOTH;
128 mode = S_IXUSR | S_IXGRP | S_IXOTH;
137 else if (euid == statb.st_uid)
140 else if (egid == statb.st_gid)
145 /* you can be in several groups */
150 * Try these things to find a positive maximum groups value:
151 * 1) sysconf(_SC_NGROUPS_MAX)
153 * 3) getgroups(0, unused)
154 * Then allocate and scan the groups array if one of these worked.
156 # if defined (HAVE_SYSCONF) && defined (_SC_NGROUPS_MAX)
157 if ((n = sysconf(_SC_NGROUPS_MAX)) == -1)
158 # endif /* _SC_NGROUPS_MAX */
161 n = getgroups(0, (GETGROUPS_T *) NULL);
164 groups = xmalloc(n * sizeof(*groups));
165 n = getgroups((int) n, groups);
167 if (groups[n] == statb.st_gid) {
174 # endif /* NGROUPS_MAX */
176 if (statb.st_mode & mode)
186 return (exp0(vp, 0));
190 exp0(Char ***vp, int ignore)
192 tcsh_number_t p1 = exp1(vp, ignore);
194 etraci("exp0 p1", p1, vp);
195 while (**vp && eq(**vp, STRor2)) {
201 exp0(vp, (ignore & TEXP_IGNORE) || p1) :
202 exp1(vp, (ignore & TEXP_IGNORE) || p1);
203 if (compat_expr || !(ignore & TEXP_IGNORE))
205 etraci("exp0 p1", p1, vp);
213 exp1(Char ***vp, int ignore)
215 tcsh_number_t p1 = exp2x(vp, ignore);
217 etraci("exp1 p1", p1, vp);
218 while (**vp && eq(**vp, STRand2)) {
223 exp1(vp, (ignore & TEXP_IGNORE) || !p1) :
224 exp2x(vp, (ignore & TEXP_IGNORE) || !p1);
226 etraci("exp1 p2", p2, vp);
227 if (compat_expr || !(ignore & TEXP_IGNORE))
229 etraci("exp1 p1", p1, vp);
237 exp2x(Char ***vp, int ignore)
239 tcsh_number_t p1 = exp2a(vp, ignore);
241 etraci("exp2x p1", p1, vp);
242 while (**vp && eq(**vp, STRor)) {
249 etraci("exp2x p2", p2, vp);
250 if (compat_expr || !(ignore & TEXP_IGNORE))
252 etraci("exp2x p1", p1, vp);
260 exp2a(Char ***vp, int ignore)
262 tcsh_number_t p1 = exp2b(vp, ignore);
264 etraci("exp2a p1", p1, vp);
265 while (**vp && eq(**vp, STRcaret)) {
272 etraci("exp2a p2", p2, vp);
273 if (compat_expr || !(ignore & TEXP_IGNORE))
275 etraci("exp2a p1", p1, vp);
283 exp2b(Char ***vp, int ignore)
285 tcsh_number_t p1 = exp2c(vp, ignore);
287 etraci("exp2b p1", p1, vp);
288 while (**vp && eq(**vp, STRand)) {
295 etraci("exp2b p2", p2, vp);
296 if (compat_expr || !(ignore & TEXP_IGNORE))
298 etraci("exp2b p1", p1, vp);
306 exp2c(Char ***vp, int ignore)
308 Char *p1 = exp3(vp, ignore);
312 cleanup_push(p1, xfree);
313 etracc("exp2c p1", p1, vp);
314 if ((i = isa(**vp, EQOP)) != 0) {
316 if (i == EQMATCH || i == NOTEQMATCH)
317 ignore |= TEXP_NOGLOB;
318 p2 = exp3(vp, ignore);
319 cleanup_push(p2, xfree);
320 etracc("exp2c p2", p2, vp);
321 if (!(ignore & TEXP_IGNORE))
349 exp3(Char ***vp, int ignore)
354 p1 = exp3a(vp, ignore);
355 etracc("exp3 p1", p1, vp);
356 while ((i = isa(**vp, RELOP)) != 0) {
358 if (**vp && eq(**vp, STRequal))
360 cleanup_push(p1, xfree);
364 cleanup_push(p2, xfree);
365 etracc("exp3 p2", p2, vp);
366 if (!(ignore & TEXP_IGNORE))
370 i = egetn(p1) > egetn(p2);
374 i = egetn(p1) >= egetn(p2);
378 i = egetn(p1) < egetn(p2);
382 i = egetn(p1) <= egetn(p2);
387 etracc("exp3 p1", p1, vp);
395 exp3a(Char ***vp, int ignore)
401 p1 = exp4(vp, ignore);
402 etracc("exp3a p1", p1, vp);
404 if (op && any("<>", op[0]) && op[0] == op[1]) {
406 cleanup_push(p1, xfree);
410 cleanup_push(p2, xfree);
411 etracc("exp3a p2", p2, vp);
413 i = egetn(p1) << egetn(p2);
415 i = egetn(p1) >> egetn(p2);
418 etracc("exp3a p1", p1, vp);
424 exp4(Char ***vp, int ignore)
429 p1 = exp5(vp, ignore);
430 etracc("exp4 p1", p1, vp);
431 while (isa(**vp, ADDOP)) {
432 const Char *op = *(*vp)++;
434 cleanup_push(p1, xfree);
438 cleanup_push(p2, xfree);
439 etracc("exp4 p2", p2, vp);
440 if (!(ignore & TEXP_IGNORE))
444 i = egetn(p1) + egetn(p2);
448 i = egetn(p1) - egetn(p2);
453 etracc("exp4 p1", p1, vp);
461 exp5(Char ***vp, int ignore)
466 p1 = exp6(vp, ignore);
467 etracc("exp5 p1", p1, vp);
469 while (isa(**vp, MULOP)) {
470 const Char *op = *(*vp)++;
471 if ((ignore & TEXP_NOGLOB) != 0) {
473 * We are just trying to get the right side of
474 * a =~ or !~ operator
480 cleanup_push(p1, xfree);
484 cleanup_push(p2, xfree);
485 etracc("exp5 p2", p2, vp);
486 if (!(ignore & TEXP_IGNORE))
490 i = egetn(p1) * egetn(p2);
509 etracc("exp5 p1", p1, vp);
517 exp6(Char ***vp, int ignore)
524 stderror(ERR_NAME | ERR_EXPRESSION);
525 if (eq(**vp, STRbang)) {
527 cp = exp6(vp, ignore);
528 cleanup_push(cp, xfree);
529 etracc("exp6 ! cp", cp, vp);
534 if (eq(**vp, STRtilde)) {
536 cp = exp6(vp, ignore);
537 cleanup_push(cp, xfree);
538 etracc("exp6 ~ cp", cp, vp);
543 if (eq(**vp, STRLparen)) {
545 ccode = exp0(vp, ignore);
546 etraci("exp6 () ccode", ccode, vp);
547 if (**vp == 0 || ***vp != ')')
548 stderror(ERR_NAME | ERR_EXPRESSION);
550 return (putn(ccode));
552 if (eq(**vp, STRLbrace)) {
554 struct command faket;
557 faket.t_dtyp = NODE_COMMAND;
558 faket.t_dflg = F_BACKQ;
559 faket.t_dcar = faket.t_dcdr = faket.t_dspr = NULL;
560 faket.t_dcom = fakecom;
561 fakecom[0] = STRfakecom;
567 stderror(ERR_NAME | ERR_MISSING, '}');
568 if (eq(*(*vp)++, STRRbrace))
571 if (ignore & TEXP_IGNORE)
572 return (Strsave(STRNULL));
574 cleanup_push(&faket, psavejob_cleanup); /* faket is only a marker */
575 if (pfork(&faket, -1) == 0) {
581 cleanup_until(&faket);
582 etraci("exp6 {} status", egetn(varval(STRstatus)), vp);
583 return (putn(egetn(varval(STRstatus)) == 0));
585 if (isa(**vp, ANYOP))
586 return (Strsave(STRNULL));
589 # define FILETESTS "erwxfdzoplstSXLbcugkmKR"
591 # define FILETESTS "erwxfdzoplstSXLbcugkmK"
593 #define FILEVALS "ZAMCDIUGNFPL"
594 if (*cp == '-' && (any(FILETESTS, cp[1]) || any(FILEVALS, cp[1])))
595 return(filetest(cp, vp, ignore));
596 etracc("exp6 default", cp, vp);
597 return (ignore & TEXP_NOGLOB ? Strsave(cp) : globone(cp, G_APPEND));
602 * Extended file tests
603 * From: John Rowe <rowe@excc.exeter.ac.uk>
606 filetest(Char *cp, Char ***vp, int ignore)
609 struct cvxstat stb, *st = NULL;
610 # define TCSH_STAT stat64
612 # define TCSH_STAT stat
613 struct stat stb, *st = NULL;
618 struct cvxstat lstb, *lst = NULL;
619 # define TCSH_LSTAT lstat64
621 # define TCSH_LSTAT lstat
622 struct stat lstb, *lst = NULL;
628 unsigned pmask = 0xffff;
630 Char *ft = cp, *dp, *ep, *strdev, *strino, *strF, *str, valtest = '\0',
632 char *string, string0[22 + MB_LEN_MAX + 1]; /* space for 64 bit octal */
637 while(any(FILETESTS, *++ft))
640 if (!*ft && *(ft - 1) == 'L')
643 if (any(FILEVALS, *ft)) {
646 * Value tests return '-1' on failure as 0 is
647 * a legitimate value for many of them.
648 * 'F' returns ':' for compatibility.
650 errval = valtest == 'F' ? STRcolon : STRminus1;
652 if (valtest == 'P' && *ft >= '0' && *ft <= '7') {
653 pmask = (char) *ft - '0';
654 while ( *++ft >= '0' && *ft <= '7' )
655 pmask = 8 * pmask + ((char) *ft - '0');
657 if (Strcmp(ft, STRcolon) == 0 && any("AMCUGP", valtest)) {
663 if (*ft || ft == cp + 1)
664 stderror(ERR_NAME | ERR_FILEINQ);
667 * Detect missing file names by checking for operator in the file name
668 * position. However, if an operator name appears there, we must make
669 * sure that there's no file by that name (e.g., "/") before announcing
670 * an error. Even this check isn't quite right, since it doesn't take
671 * globbing into account.
674 if (isa(**vp, ANYOP) && TCSH_STAT(short2str(**vp), &stb))
675 stderror(ERR_NAME | ERR_FILENAME);
678 if (ignore & TEXP_IGNORE)
679 return (Strsave(STRNULL));
680 ep = globone(dp, G_APPEND);
681 cleanup_push(ep, xfree);
687 i = !sh_access(ep, R_OK);
691 i = !sh_access(ep, W_OK);
695 i = !sh_access(ep, X_OK);
698 case 'X': /* tcsh extension, name is an executable in the path
699 * or a tcsh builtin command
704 case 't': /* SGI extension, true when file is a tty */
705 i = isatty(atoi(short2str(ep)));
711 if (tolower(*ft) == 'l') {
713 * avoid convex compiler bug.
717 if (TCSH_LSTAT(short2str(ep), lst) == -1) {
719 return (Strsave(errval));
728 * avoid convex compiler bug.
732 if (TCSH_STAT(short2str(ep), st) == -1) {
734 return (Strsave(errval));
742 i = S_ISREG(st->st_mode);
750 i = S_ISDIR(st->st_mode);
758 i = S_ISFIFO(st->st_mode);
759 #else /* !S_ISFIFO */
761 #endif /* S_ISFIFO */
766 i = S_ISOFL(st->st_dm_mode);
783 i = S_ISLNK(lst->st_mode);
791 i = S_ISSOCK(st->st_mode);
792 # else /* !S_ISSOCK */
794 # endif /* S_ISSOCK */
799 i = S_ISBLK(st->st_mode);
807 i = S_ISCHR(st->st_mode);
814 i = (S_ISUID & st->st_mode) != 0;
818 i = (S_ISGID & st->st_mode) != 0;
822 i = (S_ISVTX & st->st_mode) != 0;
826 i = st->st_size == 0;
831 i = (stb.st_dmonflags & IMIGRATED) == IMIGRATED;
836 i = stb.st_size != 0;
844 i = st->st_uid == uid;
848 * Value operators are a tcsh extension.
852 i = (tcsh_number_t) st->st_dev;
856 i = (tcsh_number_t) st->st_ino;
860 strdev = putn( (int) st->st_dev);
861 strino = putn( (int) st->st_ino);
862 strF = xmalloc((2 + Strlen(strdev) + Strlen(strino))
864 (void) Strcat(Strcat(Strcpy(strF, strdev), STRcolon), strino);
876 filnam = short2str(ep);
877 string = areadlink(filnam);
878 strF = string == NULL ? errval : str2short(string);
881 return(Strsave(strF));
890 i = (tcsh_number_t) st->st_nlink;
894 string = string0 + 1;
895 (void) xsnprintf(string, sizeof(string0) - 1, "%o",
896 pmask & (unsigned int)
897 ((S_IRWXU|S_IRWXG|S_IRWXO|S_ISUID|S_ISGID) & st->st_mode));
898 if (altout && *string != '0')
901 return(Strsave(str2short(string)));
904 if (altout && (pw = xgetpwuid(st->st_uid))) {
906 return(Strsave(str2short(pw->pw_name)));
908 i = (tcsh_number_t) st->st_uid;
912 if (altout && (gr = xgetgrgid(st->st_gid))) {
914 return(Strsave(str2short(gr->gr_name)));
916 i = (tcsh_number_t) st->st_gid;
920 i = (tcsh_number_t) st->st_size;
923 case 'A': case 'M': case 'C':
924 footime = *ft == 'A' ? st->st_atime :
925 *ft == 'M' ? st->st_mtime : st->st_ctime;
927 strF = str2short(ctime(&footime));
928 if ((str = Strchr(strF, '\n')) != NULL)
931 return(Strsave(strF));
933 i = (tcsh_number_t) footime;
939 etraci("exp6 -? i", i, vp);
948 struct wordent paraml1;
949 struct wordent *hp = ¶ml1;
951 struct wordent *wdp = hp;
953 setcopy(STRstatus, STR0, VAR_READWRITE);
956 struct wordent *new = xcalloc(1, sizeof *wdp);
962 wdp->word = Strsave(*v++);
965 cleanup_push(¶ml1, lex_cleanup);
967 t = syntax(paraml1.next, ¶ml1, 0);
968 cleanup_push(t, syntax_cleanup);
971 execute(t, -1, NULL, NULL, TRUE);
972 cleanup_until(¶ml1);
976 isa(Char *cp, int what)
979 return ((what & RESTOP) != 0);
983 if (what & ADDOP && (*cp == '+' || *cp == '-'))
985 if (what & MULOP && (*cp == '*' || *cp == '/' || *cp == '%'))
987 if (what & RESTOP && (*cp == '(' || *cp == ')' || *cp == '!' ||
988 *cp == '~' || *cp == '^' || *cp == '"'))
991 else if (cp[2] == 0) {
993 if (cp[0] == '|' && cp[1] == '&')
995 if (cp[0] == '<' && cp[1] == '<')
997 if (cp[0] == '>' && cp[1] == '>')
1007 else if (cp[0] == '!') {
1011 return (NOTEQMATCH);
1024 static tcsh_number_t
1025 egetn(const Char *cp)
1027 if (*cp && *cp != '-' && !Isdigit(*cp))
1028 stderror(ERR_NAME | ERR_EXPRESSION);
1036 etraci(const char *str, tcsh_number_t i, Char ***vp)
1038 #ifdef HAVE_LONG_LONG
1039 xprintf("%s=%lld\t", str, i);
1041 xprintf("%s=%ld\t", str, i);
1047 etracc(const char *str, const Char *cp, Char ***vp)
1049 xprintf("%s=%S\t", str, cp);