source: MondoRescue/branches/2.2.9/mindi-busybox/coreutils/test.c@ 2142

Last change on this file since 2142 was 1765, checked in by Bruno Cornec, 16 years ago

Update to busybox 1.7.2
File size: 12.6 KB
Line 
1/* vi: set sw=4 ts=4: */
2/*
3 * test implementation for busybox
4 *
5 * Copyright (c) by a whole pile of folks:
6 *
7 * test(1); version 7-like -- author Erik Baalbergen
8 * modified by Eric Gisin to be used as built-in.
9 * modified by Arnold Robbins to add SVR3 compatibility
10 * (-x -c -b -p -u -g -k) plus Korn's -L -nt -ot -ef and new -S (socket).
11 * modified by J.T. Conklin for NetBSD.
12 * modified by Herbert Xu to be used as built-in in ash.
13 * modified by Erik Andersen <andersen@codepoet.org> to be used
14 * in busybox.
15 * modified by Bernhard Fischer to be useable (i.e. a bit less bloaty).
16 *
17 * Licensed under GPLv2 or later, see file LICENSE in this tarball for details.
18 *
19 * Original copyright notice states:
20 * "This program is in the Public Domain."
21 */
22
23#include "libbb.h"
24#include <setjmp.h>
25
26/* This is a NOEXEC applet. Be very careful! */
27
28
29/* test(1) accepts the following grammar:
30 oexpr ::= aexpr | aexpr "-o" oexpr ;
31 aexpr ::= nexpr | nexpr "-a" aexpr ;
32 nexpr ::= primary | "!" primary
33 primary ::= unary-operator operand
34 | operand binary-operator operand
35 | operand
36 | "(" oexpr ")"
37 ;
38 unary-operator ::= "-r"|"-w"|"-x"|"-f"|"-d"|"-c"|"-b"|"-p"|
39 "-u"|"-g"|"-k"|"-s"|"-t"|"-z"|"-n"|"-o"|"-O"|"-G"|"-L"|"-S";
40
41 binary-operator ::= "="|"=="|"!="|"-eq"|"-ne"|"-ge"|"-gt"|"-le"|"-lt"|
42 "-nt"|"-ot"|"-ef";
43 operand ::= <any legal UNIX file name>
44*/
45
46enum token {
47 EOI,
48 FILRD,
49 FILWR,
50 FILEX,
51 FILEXIST,
52 FILREG,
53 FILDIR,
54 FILCDEV,
55 FILBDEV,
56 FILFIFO,
57 FILSOCK,
58 FILSYM,
59 FILGZ,
60 FILTT,
61 FILSUID,
62 FILSGID,
63 FILSTCK,
64 FILNT,
65 FILOT,
66 FILEQ,
67 FILUID,
68 FILGID,
69 STREZ,
70 STRNZ,
71 STREQ,
72 STRNE,
73 STRLT,
74 STRGT,
75 INTEQ,
76 INTNE,
77 INTGE,
78 INTGT,
79 INTLE,
80 INTLT,
81 UNOT,
82 BAND,
83 BOR,
84 LPAREN,
85 RPAREN,
86 OPERAND
87};
88#define is_int_op(a) (((unsigned char)((a) - INTEQ)) <= 5)
89#define is_str_op(a) (((unsigned char)((a) - STREZ)) <= 5)
90#define is_file_op(a) (((unsigned char)((a) - FILNT)) <= 2)
91#define is_file_access(a) (((unsigned char)((a) - FILRD)) <= 2)
92#define is_file_type(a) (((unsigned char)((a) - FILREG)) <= 5)
93#define is_file_bit(a) (((unsigned char)((a) - FILSUID)) <= 2)
94enum token_types {
95 UNOP,
96 BINOP,
97 BUNOP,
98 BBINOP,
99 PAREN
100};
101
102static const struct t_op {
103 char op_text[4];
104 unsigned char op_num, op_type;
105} ops[] = {
106 { "-r", FILRD , UNOP },
107 { "-w", FILWR , UNOP },
108 { "-x", FILEX , UNOP },
109 { "-e", FILEXIST, UNOP },
110 { "-f", FILREG , UNOP },
111 { "-d", FILDIR , UNOP },
112 { "-c", FILCDEV , UNOP },
113 { "-b", FILBDEV , UNOP },
114 { "-p", FILFIFO , UNOP },
115 { "-u", FILSUID , UNOP },
116 { "-g", FILSGID , UNOP },
117 { "-k", FILSTCK , UNOP },
118 { "-s", FILGZ , UNOP },
119 { "-t", FILTT , UNOP },
120 { "-z", STREZ , UNOP },
121 { "-n", STRNZ , UNOP },
122 { "-h", FILSYM , UNOP }, /* for backwards compat */
123
124 { "-O" , FILUID , UNOP },
125 { "-G" , FILGID , UNOP },
126 { "-L" , FILSYM , UNOP },
127 { "-S" , FILSOCK, UNOP },
128 { "=" , STREQ , BINOP },
129 { "==" , STREQ , BINOP },
130 { "!=" , STRNE , BINOP },
131 { "<" , STRLT , BINOP },
132 { ">" , STRGT , BINOP },
133 { "-eq", INTEQ , BINOP },
134 { "-ne", INTNE , BINOP },
135 { "-ge", INTGE , BINOP },
136 { "-gt", INTGT , BINOP },
137 { "-le", INTLE , BINOP },
138 { "-lt", INTLT , BINOP },
139 { "-nt", FILNT , BINOP },
140 { "-ot", FILOT , BINOP },
141 { "-ef", FILEQ , BINOP },
142 { "!" , UNOT , BUNOP },
143 { "-a" , BAND , BBINOP },
144 { "-o" , BOR , BBINOP },
145 { "(" , LPAREN , PAREN },
146 { ")" , RPAREN , PAREN },
147};
148
149
150#if ENABLE_FEATURE_TEST_64
151typedef int64_t arith_t;
152#else
153typedef int arith_t;
154#endif
155
156/* Cannot eliminate these static data (do the G trick)
157 * because of test_main usage from other applets */
158static char **t_wp;
159static struct t_op const *t_wp_op;
160static gid_t *group_array;
161static int ngroups;
162static jmp_buf leaving;
163
164static enum token t_lex(char *s);
165static arith_t oexpr(enum token n);
166static arith_t aexpr(enum token n);
167static arith_t nexpr(enum token n);
168static int binop(void);
169static arith_t primary(enum token n);
170static int filstat(char *nm, enum token mode);
171static arith_t getn(const char *s);
172/* UNUSED
173static int newerf(const char *f1, const char *f2);
174static int olderf(const char *f1, const char *f2);
175static int equalf(const char *f1, const char *f2);
176*/
177static int test_eaccess(char *path, int mode);
178static int is_a_group_member(gid_t gid);
179static void initialize_group_array(void);
180
181int test_main(int argc, char **argv)
182{
183 int res;
184 const char *arg0;
185 bool _off;
186
187 arg0 = bb_basename(argv[0]);
188 if (arg0[0] == '[') {
189 --argc;
190 if (!arg0[1]) { /* "[" ? */
191 if (NOT_LONE_CHAR(argv[argc], ']')) {
192 bb_error_msg("missing ]");
193 return 2;
194 }
195 } else { /* assuming "[[" */
196 if (strcmp(argv[argc], "]]") != 0) {
197 bb_error_msg("missing ]]");
198 return 2;
199 }
200 }
201 argv[argc] = NULL;
202 }
203
204 res = setjmp(leaving);
205 if (res)
206 return res;
207
208 /* resetting ngroups is probably unnecessary. it will
209 * force a new call to getgroups(), which prevents using
210 * group data fetched during a previous call. but the
211 * only way the group data could be stale is if there's
212 * been an intervening call to setgroups(), and this
213 * isn't likely in the case of a shell. paranoia
214 * prevails...
215 */
216 ngroups = 0;
217
218 /* Implement special cases from POSIX.2, section 4.62.4 */
219 if (argc == 1)
220 return 1;
221 if (argc == 2)
222 return *argv[1] == '\0';
223//assert(argc);
224 /* remember if we saw argc==4 which wants *no* '!' test */
225 _off = argc - 4;
226 if (_off ?
227 (LONE_CHAR(argv[1], '!'))
228 : (argv[1][0] != '!' || argv[1][1] != '\0'))
229 {
230 if (argc == 3)
231 return *argv[2] != '\0';
232
233 t_lex(argv[2 + _off]);
234 if (t_wp_op && t_wp_op->op_type == BINOP) {
235 t_wp = &argv[1 + _off];
236 return binop() == _off;
237 }
238 }
239 t_wp = &argv[1];
240 res = !oexpr(t_lex(*t_wp));
241
242 if (*t_wp != NULL && *++t_wp != NULL) {
243 bb_error_msg("%s: unknown operand", *t_wp);
244 return 2;
245 }
246 return res;
247}
248
249static void syntax(const char *op, const char *msg) ATTRIBUTE_NORETURN;
250static void syntax(const char *op, const char *msg)
251{
252 if (op && *op) {
253 bb_error_msg("%s: %s", op, msg);
254 } else {
255 bb_error_msg("%s: %s"+4, msg);
256 }
257 longjmp(leaving, 2);
258}
259
260static arith_t oexpr(enum token n)
261{
262 arith_t res;
263
264 res = aexpr(n);
265 if (t_lex(*++t_wp) == BOR) {
266 return oexpr(t_lex(*++t_wp)) || res;
267 }
268 t_wp--;
269 return res;
270}
271
272static arith_t aexpr(enum token n)
273{
274 arith_t res;
275
276 res = nexpr(n);
277 if (t_lex(*++t_wp) == BAND)
278 return aexpr(t_lex(*++t_wp)) && res;
279 t_wp--;
280 return res;
281}
282
283static arith_t nexpr(enum token n)
284{
285 if (n == UNOT)
286 return !nexpr(t_lex(*++t_wp));
287 return primary(n);
288}
289
290static arith_t primary(enum token n)
291{
292 arith_t res;
293
294 if (n == EOI) {
295 syntax(NULL, "argument expected");
296 }
297 if (n == LPAREN) {
298 res = oexpr(t_lex(*++t_wp));
299 if (t_lex(*++t_wp) != RPAREN)
300 syntax(NULL, "closing paren expected");
301 return res;
302 }
303 if (t_wp_op && t_wp_op->op_type == UNOP) {
304 /* unary expression */
305 if (*++t_wp == NULL)
306 syntax(t_wp_op->op_text, "argument expected");
307 if (n == STREZ)
308 return t_wp[0][0] == '\0';
309 if (n == STRNZ)
310 return t_wp[0][0] != '\0';
311 if (n == FILTT)
312 return isatty(getn(*t_wp));
313 return filstat(*t_wp, n);
314 }
315
316 t_lex(t_wp[1]);
317 if (t_wp_op && t_wp_op->op_type == BINOP) {
318 return binop();
319 }
320
321 return t_wp[0][0] != '\0';
322}
323
324static int binop(void)
325{
326 const char *opnd1, *opnd2;
327 struct t_op const *op;
328 arith_t val1, val2;
329
330 opnd1 = *t_wp;
331 (void) t_lex(*++t_wp);
332 op = t_wp_op;
333
334 opnd2 = *++t_wp;
335 if (opnd2 == NULL)
336 syntax(op->op_text, "argument expected");
337
338 if (is_int_op(op->op_num)) {
339 val1 = getn(opnd1);
340 val2 = getn(opnd2);
341 if (op->op_num == INTEQ)
342 return val1 == val2;
343 if (op->op_num == INTNE)
344 return val1 != val2;
345 if (op->op_num == INTGE)
346 return val1 >= val2;
347 if (op->op_num == INTGT)
348 return val1 > val2;
349 if (op->op_num == INTLE)
350 return val1 <= val2;
351 if (op->op_num == INTLT)
352 return val1 < val2;
353 }
354 if (is_str_op(op->op_num)) {
355 val1 = strcmp(opnd1, opnd2);
356 if (op->op_num == STREQ)
357 return val1 == 0;
358 if (op->op_num == STRNE)
359 return val1 != 0;
360 if (op->op_num == STRLT)
361 return val1 < 0;
362 if (op->op_num == STRGT)
363 return val1 > 0;
364 }
365 /* We are sure that these three are by now the only binops we didn't check
366 * yet, so we do not check if the class is correct:
367 */
368/* if (is_file_op(op->op_num)) */
369 {
370 struct stat b1, b2;
371
372 if (stat(opnd1, &b1) || stat(opnd2, &b2))
373 return 0; /* false, since at least one stat failed */
374 if (op->op_num == FILNT)
375 return b1.st_mtime > b2.st_mtime;
376 if (op->op_num == FILOT)
377 return b1.st_mtime < b2.st_mtime;
378 if (op->op_num == FILEQ)
379 return b1.st_dev == b2.st_dev && b1.st_ino == b2.st_ino;
380 }
381 return 1; /* NOTREACHED */
382}
383
384static int filstat(char *nm, enum token mode)
385{
386 struct stat s;
387 int i = i; /* gcc 3.x thinks it can be used uninitialized */
388
389 if (mode == FILSYM) {
390#ifdef S_IFLNK
391 if (lstat(nm, &s) == 0) {
392 i = S_IFLNK;
393 goto filetype;
394 }
395#endif
396 return 0;
397 }
398
399 if (stat(nm, &s) != 0)
400 return 0;
401 if (mode == FILEXIST)
402 return 1;
403 if (is_file_access(mode)) {
404 if (mode == FILRD)
405 i = R_OK;
406 if (mode == FILWR)
407 i = W_OK;
408 if (mode == FILEX)
409 i = X_OK;
410 return test_eaccess(nm, i) == 0;
411 }
412 if (is_file_type(mode)) {
413 if (mode == FILREG)
414 i = S_IFREG;
415 if (mode == FILDIR)
416 i = S_IFDIR;
417 if (mode == FILCDEV)
418 i = S_IFCHR;
419 if (mode == FILBDEV)
420 i = S_IFBLK;
421 if (mode == FILFIFO) {
422#ifdef S_IFIFO
423 i = S_IFIFO;
424#else
425 return 0;
426#endif
427 }
428 if (mode == FILSOCK) {
429#ifdef S_IFSOCK
430 i = S_IFSOCK;
431#else
432 return 0;
433#endif
434 }
435 filetype:
436 return ((s.st_mode & S_IFMT) == i);
437 }
438 if (is_file_bit(mode)) {
439 if (mode == FILSUID)
440 i = S_ISUID;
441 if (mode == FILSGID)
442 i = S_ISGID;
443 if (mode == FILSTCK)
444 i = S_ISVTX;
445 return ((s.st_mode & i) != 0);
446 }
447 if (mode == FILGZ)
448 return s.st_size > 0L;
449 if (mode == FILUID)
450 return s.st_uid == geteuid();
451 if (mode == FILGID)
452 return s.st_gid == getegid();
453 return 1; /* NOTREACHED */
454}
455
456static enum token t_lex(char *s)
457{
458 const struct t_op *op;
459
460 t_wp_op = NULL;
461 if (s == NULL) {
462 return EOI;
463 }
464
465 op = ops;
466 do {
467 if (strcmp(s, op->op_text) == 0) {
468 t_wp_op = op;
469 return op->op_num;
470 }
471 op++;
472 } while (op < ops + ARRAY_SIZE(ops));
473
474 return OPERAND;
475}
476
477/* atoi with error detection */
478//XXX: FIXME: duplicate of existing libbb function?
479static arith_t getn(const char *s)
480{
481 char *p;
482#if ENABLE_FEATURE_TEST_64
483 long long r;
484#else
485 long r;
486#endif
487
488 errno = 0;
489#if ENABLE_FEATURE_TEST_64
490 r = strtoll(s, &p, 10);
491#else
492 r = strtol(s, &p, 10);
493#endif
494
495 if (errno != 0)
496 syntax(s, "out of range");
497
498 if (*(skip_whitespace(p)))
499 syntax(s, "bad number");
500
501 return r;
502}
503
504/* UNUSED
505static int newerf(const char *f1, const char *f2)
506{
507 struct stat b1, b2;
508
509 return (stat(f1, &b1) == 0 &&
510 stat(f2, &b2) == 0 && b1.st_mtime > b2.st_mtime);
511}
512
513static int olderf(const char *f1, const char *f2)
514{
515 struct stat b1, b2;
516
517 return (stat(f1, &b1) == 0 &&
518 stat(f2, &b2) == 0 && b1.st_mtime < b2.st_mtime);
519}
520
521static int equalf(const char *f1, const char *f2)
522{
523 struct stat b1, b2;
524
525 return (stat(f1, &b1) == 0 &&
526 stat(f2, &b2) == 0 &&
527 b1.st_dev == b2.st_dev && b1.st_ino == b2.st_ino);
528}
529*/
530
531/* Do the same thing access(2) does, but use the effective uid and gid,
532 and don't make the mistake of telling root that any file is
533 executable. */
534static int test_eaccess(char *path, int mode)
535{
536 struct stat st;
537 unsigned int euid = geteuid();
538
539 if (stat(path, &st) < 0)
540 return -1;
541
542 if (euid == 0) {
543 /* Root can read or write any file. */
544 if (mode != X_OK)
545 return 0;
546
547 /* Root can execute any file that has any one of the execute
548 bits set. */
549 if (st.st_mode & (S_IXUSR | S_IXGRP | S_IXOTH))
550 return 0;
551 }
552
553 if (st.st_uid == euid) /* owner */
554 mode <<= 6;
555 else if (is_a_group_member(st.st_gid))
556 mode <<= 3;
557
558 if (st.st_mode & mode)
559 return 0;
560
561 return -1;
562}
563
564static void initialize_group_array(void)
565{
566 ngroups = getgroups(0, NULL);
567 if (ngroups > 0) {
568 /* FIXME: ash tries so hard to not die on OOM,
569 * and we spoil it with just one xrealloc here */
570 /* We realloc, because test_main can be entered repeatedly by shell.
571 * Testcase (ash): 'while true; do test -x some_file; done'
572 * and watch top. (some_file must have owner != you) */
573 group_array = xrealloc(group_array, ngroups * sizeof(gid_t));
574 getgroups(ngroups, group_array);
575 }
576}
577
578/* Return non-zero if GID is one that we have in our groups list. */
579//XXX: FIXME: duplicate of existing libbb function?
580// see toplevel TODO file:
581// possible code duplication ingroup() and is_a_group_member()
582static int is_a_group_member(gid_t gid)
583{
584 int i;
585
586 /* Short-circuit if possible, maybe saving a call to getgroups(). */
587 if (gid == getgid() || gid == getegid())
588 return 1;
589
590 if (ngroups == 0)
591 initialize_group_array();
592
593 /* Search through the list looking for GID. */
594 for (i = 0; i < ngroups; i++)
595 if (gid == group_array[i])
596 return 1;
597
598 return 0;
599}
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